Charging system and charging method

Abstract

The embodiment of the application discloses a charging system and a charging method. The charging system comprises a charging device and a power consumption equipment. The charging device comprises an energy storage device. The charging device is configured to determine charging demand information of the power consumption equipment in response to a charging event. The charging device is configured to determine a target charging mode of the charging device for charging the power consumption equipment based on the charging demand information. The target charging mode corresponds to target charging parameters. The charging device comprises an energy storage device. The charging device is configured to charge the power consumption equipment based on the target charging parameters corresponding to the target charging mode. In the case that the target charging mode comprises a first charging mode, the target charging parameters corresponding to the first charging mode comprise first charging parameters. The charging power indicated by the first charging parameters is greater than 300 kilowatts.

Description

[0001] Cross Reference to Related Applications

[0002] This application claims priority to the following patent applications, the contents of which are incorporated herein by reference in their entirety:

[0003] PCT International Patent Application No. PCT / CN2024 / 093513, entitled "Charging device, charging pile and charging and storing system", filed on May 15, 2024;

[0004] PCT International Patent Application No. PCT / CN2024 / 102652, entitled "Battery cell, battery and electric device", filed on June 28, 2024;

[0005] PCT International Patent Application No. PCT / CN2024093517, entitled "Charging method, system, device, storage medium and program product", filed on May 15, 2024. TECHNICAL FIELD

[0006] The present application relates to the technical field of charging, in particular to a charging system and a charging method. BACKGROUND

[0007] With the rapid increase of electric equipment, the problems of slow charging of electric equipment and poor experience need to be solved. In order to meet the charging needs of electric equipment in different scenes, various charging modes have appeared. However, there is no good method to determine the appropriate charging mode for charging electric equipment. SUMMARY

[0008] Therefore, the embodiments of the present application provide at least a charging system and a charging method.

[0009] In a first aspect, the present application provides a charging method, the charging method comprising:

[0010] In response to a charging event, determining charging demand information of the electric equipment;

[0011] Based on the charging demand information, determining a target charging mode of the charging device for charging the electric equipment, wherein the target charging mode corresponds to target charging parameters; the charging device comprises an energy storage device;

[0012] Based on the target charging parameters corresponding to the target charging mode, charging the electric equipment;

[0013] obtain a current state of charge value and / or a remaining energy state value of the energy storage device, and determine that the energy storage device supports charging the electrical device according to a charging power corresponding to a first charging mode in a case where the state of charge value is greater than or equal to a first state of charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, the first state of charge threshold being 50%, and the first remaining energy threshold being 50%;

[0014] In a case where the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts.

[0015] In the embodiments of the present application, the target charging mode of the charging device for charging the electrical device is determined based on the charging demand information of the electrical device, and then the electrical device is charged based on the target charging parameter corresponding to the target charging mode. In this way, in a case where there are multiple charging modes, the most suitable charging mode for the electrical device can be determined based on the charging demand information of the electrical device.

[0016] In some embodiments, the input power of the energy storage device is less than 150 kilowatts, and the output power of the energy storage device is greater than or equal to 300 kilowatts in the first charging mode.

[0017] In the embodiments of the present application, the input power and output power ranges of the energy storage device are provided, and the normal operation of the energy storage device is determined by controlling the input power or output power of the energy storage device within the corresponding range.

[0018] In some embodiments, the charging mode of the charging device further includes a second charging mode, and the second charging parameter in the second charging mode indicates a charging power less than or equal to 300 kilowatts.

[0019] The charging method further includes:

[0020] In a case where the target charging mode is the first charging mode and the energy storage device cannot charge the electrical device according to the first charging parameter, the second charging parameter corresponding to the second charging mode is determined.

[0021] The electrical device is charged according to the second charging parameter.

[0022] In the embodiments of the present application, in a case where it is determined that the energy storage device does not support charging the electrical device according to the first charging mode, the second charging parameter corresponding to the second charging mode is directly determined, and the electrical device is charged according to the second charging parameter, thereby reducing the time length of the determination process of the target charging mode, and further improving the charging time length of the electrical device.

[0023] In some embodiments, the charging modes of the charging device further include a third charging mode, and a third charging parameter in the third charging mode indicates a charging power smaller than the second charging parameter in the second charging mode;

[0024] The charging method further includes:

[0025] In a case where the target charging mode is the second charging mode and the energy storage device is unable to charge the electrical device according to the second charging parameter, determining a third charging parameter corresponding to a third charging mode;

[0026] Charging the electrical device according to the third charging parameter.

[0027] In the embodiments of the present application, in a case where it is determined that the energy storage device does not support charging the electrical device according to the second charging mode, the third charging parameter corresponding to the third charging mode is directly determined, and the electrical device is charged according to the third charging parameter, thereby reducing the time length of the determination process of the target charging mode, and further improving the charging time length of the electrical device.

[0028] In some embodiments, the target charging parameter further indicates a target charging manner;

[0029] In a case where the target charging manner includes the first charging manner, charging the electrical device based on the target charging parameter corresponding to the target charging mode includes:

[0030] Providing, by the energy storage device, all of the charging power indicated by the target charging parameter to the electrical device;

[0031] In a case where the target charging manner includes the second charging manner, charging the electrical device based on the target charging parameter corresponding to the target charging mode includes:

[0032] Providing, by the grid, a part of the charging power indicated by the target charging parameter to the electrical device, and providing, by the energy storage device, another part of the charging power indicated by the target charging parameter to the electrical device; the part of the charging power includes a part or all of the charging power that can be provided by the grid.

[0033] In the embodiments of the present application, two charging methods are provided, in which the energy storage device provides power to the electrical device, and the energy storage device and the grid jointly provide power to the electrical device, thereby matching the corresponding charging method according to the charging demand of different scenes.

[0034] In some embodiments, before the above charging of the electrical device based on the target charging parameter corresponding to the target charging mode, the charging method further includes:

[0035] Determining an estimated charging time period;

[0036] In a case where the estimated charging period falls within the first period of power supply of the power grid, the target charging mode is determined as the first charging mode;

[0037] In a case where the estimated charging period falls within the second period, the target charging mode is determined as the second charging mode.

[0038] In a case where a first sub-period of the estimated charging period falls within the first period of power supply of the power grid, the target charging mode in the first sub-period is determined as the first charging mode, and in a case where a second sub-period of the estimated charging period falls within the second period of power supply of the power grid, the target charging mode in the second sub-period is determined as the second charging mode.

[0039] The first period and the second period are different.

[0040] In the embodiments of the present application, the charging mode corresponding to the period is determined based on the power price of the period, so that the first charging mode is used when the power price is the highest, and the second charging mode is used in other periods, thereby saving the charging cost of the electrical equipment.

[0041] In some embodiments, the energy storage device and / or the charging device satisfy one or more of the following conditions:

[0042] The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3;

[0043] The energy density of the energy storage device is greater than or equal to 380 watt-hours per liter;

[0044] The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:4.

[0045] In some embodiments, the ratio between the rated energy of the energy storage device and the rated power of the energy storage device is less than or equal to 1:4.

[0046] In some embodiments, based on the charging demand information, a target charging mode of the charging device for charging the electrical equipment is determined, including:

[0047] Based on the charging demand information, a target charging parameter of the charging device for charging the electrical equipment is determined from at least one charging mode of the charging device;

[0048] The at least one charging mode of the charging device includes a first charging mode.

[0049] In the embodiments of the present application, the target charging parameter of the charging device for charging the electrical equipment is determined through the charging demand information of the electrical equipment, and by this method, the charging device can charge the electrical equipment with the target charging parameter.

[0050] In some embodiments, the charging demand information comprises an expected charging duration;

[0051] Based on the charging demand information, a target charging parameter of the charging device for charging the electrical equipment is determined from at least one charging mode of the charging device, comprising:

[0052] The estimated charging duration corresponding to each charging mode of the charging device is determined.

[0053] The duration difference between the expected charging duration and the estimated charging duration of each charging mode is determined.

[0054] The charging mode corresponding to the minimum duration difference among all duration differences is determined as the target charging mode.

[0055] In the embodiments of the present application, the target charging mode is determined based on the difference between the expected charging duration and the estimated charging duration of each charging mode. By this method, the charging mode that best matches the user's charging demand can be determined.

[0056] In some embodiments, the charging method further comprises:

[0057] Based on the state of charge value and / or the remaining energy state value, it is determined whether the energy storage device can charge the electrical equipment at the target charging parameter;

[0058] In the case where it is determined that the energy storage device can charge the electrical equipment at the target charging parameter, the electrical equipment is charged based on the target charging parameter.

[0059] In the embodiments of the present application, firstly, the current state of charge value and / or the remaining energy state value of the energy storage device is obtained. Then, based on the state of charge value and the remaining energy value, in the case where it is determined that the energy storage device supports charging the electrical equipment in the target charging mode, the electrical equipment is charged at the target charging parameter corresponding to the target charging mode.

[0060] In some embodiments, based on the state of charge value and / or the remaining energy state value, it is determined whether the energy storage device can charge the electrical equipment at the target charging parameter, comprising:

[0061] In the case where the state of charge value is less than a first state of charge threshold and greater than or equal to a second state of charge threshold, and / or the remaining energy state value is less than a first remaining energy threshold and greater than or equal to a second remaining energy threshold, it is determined that the energy storage device supports charging the electrical equipment at the charging power corresponding to the second charging mode.

[0062] In the embodiments of the present application, based on the current state of charge value and / or the remaining energy state value, the current chargeable mode that the energy storage device can support can be directly determined, so that the charging power corresponding to the supported chargeable mode of the energy storage device is quickly determined to charge the electrical equipment.

[0063] In some embodiments, the charging method further includes:

[0064] In the case that the state of charge value is less than the first state of charge threshold, and / or the remaining energy state value is less than the first remaining energy threshold, a first prompt message is output, and the first prompt message is used to represent that the charging device currently does not support the first chargeable mode and needs to be switched to the second chargeable mode or the third chargeable mode;

[0065] In the case that the state of charge value is less than the second state of charge threshold, and / or the remaining energy state value is less than the second remaining energy threshold, a second prompt message is output, and the second prompt message is used to represent that the charging device currently does not support the second chargeable mode and needs to be switched to the third chargeable mode;

[0066] In response to the chargeable mode selected based on the first prompt message or the second prompt message, the selected chargeable mode is determined as the target chargeable mode.

[0067] In the embodiments of the present application, in the case that it is determined that the energy storage device does not support charging the electrical equipment according to the target chargeable mode, information for prompting the user that the target chargeable mode is not supported and the selectable chargeable modes is output, and the user can reselect the target chargeable mode according to the prompted chargeable modes, and then charge the electrical equipment according to the target charging parameters corresponding to the selected target chargeable mode.

[0068] In some embodiments, in response to the charging event, the charging demand information of the electrical equipment is determined, including:

[0069] In response to the charging event, a charging request message sent by the charging gun or the user end is received, and the attribute information of the battery of the electrical equipment is included in the charging request message; the attribute information of the battery at least includes: a plurality of charging parameters suitable for the electrical equipment;

[0070] Based on the attribute information of the battery, the charging demand information of the electrical equipment is determined.

[0071] In the embodiments of the present application, a method for determining the charging demand information of the electrical equipment is proposed, so that the determination of the charging demand information of the electrical equipment is completed in this way.

[0072] In some embodiments, based on the attribute information of the battery, the charging demand information of the electrical equipment is determined, including:

[0073] The charging demand information of the electrical equipment is determined based on the attribute information of the battery and the charging strategy. The charging strategy is set for the electrical equipment or the charging device.

[0074] In the embodiments of the present application, the charging demand information of the electrical equipment can be determined based on the attribute information of the battery and the charging strategy, and then the target charging mode of the charging device can be matched through the charging demand information.

[0075] In some embodiments, the charging demand information of the electrical equipment is determined based on the attribute information of the battery, including:

[0076] Based on the attribute information of the battery, the estimated consumption parameter values corresponding to the plurality of charging modes are determined and output, and the estimated consumption parameters include estimated charging time and / or estimated charging cost.

[0077] In response to the selection operation of the plurality of estimated consumption parameter values, the selected estimated consumption parameter value is determined as the charging demand information of the electrical equipment.

[0078] In the embodiments of the present application, the estimated consumption parameter values corresponding to the plurality of charging modes are determined, and then the selected estimated parameter value is determined as the charging demand information of the electrical equipment.

[0079] On the other hand, a charging method, the charging method comprising:

[0080] In response to the charging event, the estimated charging period of the electrical equipment and the target charging mode of the charging device for charging the electrical equipment are determined based on the charging demand information of the electrical equipment, and the charging device includes an energy storage device.

[0081] The target charging mode for charging the electrical equipment is determined in the estimated charging period.

[0082] The electrical equipment is charged in the target charging mode based on the target charging parameters corresponding to the target charging mode.

[0083] The current state of charge value and / or the remaining energy state value of the energy storage device are obtained, and in the case that the state of charge value is greater than or equal to the first state of charge threshold value, and / or the remaining energy state value is greater than or equal to the first remaining energy threshold value, it is determined that the energy storage device supports charging the electrical equipment according to the charging power corresponding to the first charging mode, and the first state of charge threshold value is 50%, and the first remaining energy threshold value is 50%.

[0084] In the case that the target charging mode includes the first charging mode, the target charging parameters corresponding to the first charging mode include the first charging parameters, and the charging power indicated by the first charging parameters is greater than 300 kilowatts.

[0085] In the embodiments of the present application, based on the demand information of the electric equipment, the estimated charging period and the target charging mode of the electric equipment are determined, so that the charging method of the estimated charging period is determined based on the estimated charging period. In this way, different charging methods can be adopted in different time periods with different power prices, so as to save the charging cost of the electric equipment, thereby attracting more users to charge here and realizing more revenue.

[0086] In another aspect, the embodiments of the present application provide a charging method, the method comprising: in response to selection of a charging mode, obtaining a current state of charge value and / or a remaining energy state value of an energy storage device in a charging device; based on the state of charge value and / or the remaining energy state value, determining whether the energy storage device can charge the electric equipment with target charging parameters corresponding to the target charging mode; the target charging mode is a charging mode of the charging device for charging the electric equipment, and in the case that the state of charge value is greater than or equal to a first state of charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, it is determined that the energy storage device supports charging the electric equipment with a charging power corresponding to a first charging mode, the first state of charge threshold is 50%, and the first remaining energy threshold is 50%; in the case that it is determined that the energy storage device can charge the electric equipment with the target charging parameters, charging the electric equipment based on the target charging parameters;

[0087] Among them, the energy storage device and / or the charging device meet one or more of the following conditions:

[0088] The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3;

[0089] The energy density of the energy storage device is greater than or equal to 380 watt-hours per liter;

[0090] The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:4

[0091] In the embodiments of the present application, first, the current state of charge value and / or the remaining energy state value of the energy storage device are obtained, and then based on the state of charge value and the remaining energy value, in the case that it is determined that the energy storage device supports charging the electric equipment according to the target charging mode, the electric equipment is charged with target charging parameters corresponding to the target charging mode.

[0092] In another aspect, the embodiments of the present application provide a charging method, which comprises: in response to selection of a first charging mode, obtaining a current state of charge value and / or a remaining energy state value of an energy storage device in a charging device; determining that the energy storage device supports charging of an electrical device according to a charging power corresponding to the first charging mode, when the state of charge value is greater than or equal to a first state of charge threshold value and / or the remaining energy state value is greater than or equal to a first remaining energy threshold value, the first state of charge threshold value being 50%, and the first remaining energy threshold value being 50%; wherein the charging power indicated by a first charging parameter in the first charging mode is greater than 300 kW.

[0093] In the embodiments of the present application, when the first charging mode is selected, it is determined that the energy storage device supports charging of the electrical device according to the charging power corresponding to the first charging mode based on the current state of charge value and / or the remaining energy state value of the energy storage device, so that the electrical device can complete charging in the first charging mode.

[0094] In another aspect, the embodiments of the present application provide a charging method, which comprises: obtaining a current state of charge value and / or a remaining energy state value of an energy storage device, and determining that the energy storage device supports charging of an electrical device according to a charging power corresponding to a first charging mode, when the state of charge value is greater than or equal to a first state of charge threshold value and / or the remaining energy state value is greater than or equal to a first remaining energy threshold value, the first state of charge threshold value being 50%, and the first remaining energy threshold value being 50%.

[0095] In response to selection of a second charging mode, a current state of charge value and / or a remaining energy state value of an energy storage device in a charging device are obtained; it is determined that the energy storage device supports charging of an electrical device according to a charging power corresponding to the second charging mode, when the current state of charge value is less than the first state of charge threshold value and greater than or equal to a second state of charge threshold value and / or the remaining energy state value is less than the first remaining energy threshold value and greater than or equal to a second remaining energy threshold value; wherein the charging power indicated by a second charging parameter in the second charging mode is less than or equal to 300 kW.

[0096] In the embodiments of the present application, when the second charging mode is selected, it is determined that the energy storage device supports charging of the electrical device according to the charging power corresponding to the second charging mode based on the current state of charge value and / or the remaining energy state value of the energy storage device, so that the electrical device can complete charging in the second charging mode.

[0097] In another aspect, the embodiments of the present application provide a charging method, the method comprising: in response to selection of a charging mode, obtaining a current state of charge value and / or a remaining energy state value of an energy storage device in a charging device; wherein the charging mode comprises a first charging mode, a first charging parameter in the first charging mode indicates a charging power greater than 300 kW, in a case that the state of charge value is greater than or equal to a first state of charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, it is determined that the energy storage device supports charging of an electric device according to a charging power corresponding to the first charging mode, the first state of charge threshold is 50%, and the first remaining energy threshold is 50%; in a case that the state of charge value is greater than a third state of charge threshold and / or the remaining energy state value is greater than a third remaining energy threshold, the energy storage device provides all power of the charging power indicated by the charging parameter in the charging mode to the electric device;

[0098] In the embodiments of the present application, the energy storage device and / or the charging device satisfy one or more of the following conditions:

[0099] The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3;

[0100] The energy density of the energy storage device is greater than or equal to 380 Wh / L;

[0101] The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:4.

[0102] In the embodiments of the present application, based on the current state of charge value and / or the remaining energy state value of the energy storage device, it can be determined that the energy storage device can support the operating mode of providing all power of the charging power indicated by the charging parameter in the charging mode to the electric device, so that the energy storage device can be controlled to charge the electric device alone.

[0103] In another aspect, the embodiments of the present application provide a charging method, the method comprising: in response to a charging event, sending a state parameter of an energy storage device in a charging device to a charging control device of the charging device; the state parameter comprises one or more of the following: a state of charge value, a remaining energy state value; receiving discharge parameters of the energy storage device sent by the charging control device, wherein the discharge parameters of the energy storage device are determined based on a target charging mode for charging an electric device and the state parameter; in a case that a circuit between the energy storage device and a bidirectional DC / DC module of the charging device is conductive, controlling the energy storage device to discharge according to the discharge parameters; obtaining a current state of charge value and / or a remaining energy state value of the energy storage device, in a case that the state of charge value is greater than or equal to a first state of charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, it is determined that the energy storage device supports charging of the electric device according to a charging power corresponding to the first charging mode, the first state of charge threshold is 50%, and the first remaining energy threshold is 50%.

[0104] In a case where the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a discharge parameter of the energy storage device, and the discharge power indicated by the discharge parameter of the energy storage device is greater than 300 kilowatts.

[0105] In the embodiments of the present application, in a case where the discharge parameter of the energy storage device determined based on the target charging mode of charging the electrical equipment and the state parameter of the energy storage device is received by the charging control device, the energy storage device is controlled to discharge according to the discharge parameter, so that the charging device can charge the electrical equipment with the target charging parameter corresponding to the target charging mode.

[0106] On the other hand, the embodiments of the present application provide a charging control device, which comprises:

[0107] The first determination module is configured to determine charging demand information of the electrical equipment in response to a charging event;

[0108] The second determination module is configured to determine a target charging mode of charging the electrical equipment by the charging device based on the charging demand information, wherein the target charging mode corresponds to a target charging parameter; and the charging device comprises an energy storage device.

[0109] The first charging module is configured to charge the electrical equipment based on the target charging parameter corresponding to the target charging mode.

[0110] In a case where the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts.

[0111] On the other hand, the embodiments of the present application provide a charging system, which comprises a charging device and an electrical equipment, wherein the charging device comprises an energy storage device.

[0112] The charging device is configured to determine charging demand information of the electrical equipment in response to a charging event; determine a target charging mode of charging the electrical equipment by the charging device based on the charging demand information, wherein the target charging mode corresponds to a target charging parameter; and the charging device comprises an energy storage device; and charge the electrical equipment based on the target charging parameter corresponding to the target charging mode.

[0113] In a case where the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts.

[0114] In another aspect, an embodiment of the present application provides a charging device, comprising a charging and discharging circuit and a charging control device; the charging control device is configured to implement the steps of the above method when executing a program.

[0115] In some embodiments, the charging device comprises

[0116] a storage module, the storage module comprising one or more storage units, each storage unit having a first positive power supply end and a first negative power supply end, the one or more storage units being connected to a second positive power supply end and a second negative power supply end of the storage module through the first positive power supply end and the first negative power supply end, the storage module being configured to provide a first direct current;

[0117] a charging module, the charging module being connected to the second positive power supply end and the second negative power supply end of the storage module, the charging module being configured to output a charge based on the first direct current, the maximum charge output power of the charging module being greater than or equal to 350 kilowatts, and / or the rated charge output power of the charging module being greater than or equal to 290 kilowatts.

[0118] In some embodiments, the charging device further comprises an input module, the input module being configured to provide charging energy for each storage unit. The input module is provided to charge the storage units to replenish the energy of the storage units.

[0119] In some embodiments, the ratio between the maximum charge output power of the charging module and the maximum output power of the input module is greater than 1 and less than or equal to 15, and / or the ratio between the rated charge output power of the charging module and the rated output power of the input module is greater than 1 and less than or equal to 15.

[0120] In this way, the current surge, overheating and other problems caused by the charging module due to instantaneous excessive power input can be reduced. The input module charges the storage module at a small power, and the storage module outputs a controllable large power to the charging module. The storage module can flexibly adjust the output power according to the amount of electricity stored and the power demand of the electrical equipment, so that the charging device can reasonably distribute the electrical energy, reduce unnecessary energy consumption, improve the performance-price ratio of the charging device, and enable the charging device to run smoothly when charging at a small power and outputting at a large power.

[0121] In some embodiments, each storage unit comprises a battery subunit, and the ratio between the rated output power of the input module and the rated energy of the battery subunit is greater than or equal to 1 / n1, where n1 is in the range of 1-4.

[0122] Thus, when the input power is small and the output power is large, the battery sub-units can charge the electrical equipment at different charging rates, so as to adjust the charging rate according to the charging demand of the electrical equipment in the charging process or different charging time periods, so that the charging device can reasonably utilize the stored energy to charge the electrical equipment, so that the energy stored in the charging device is effectively utilized, the performance-cost ratio of the entire charging device is improved, and the stability of the charging device is improved. In different charging processes, the charging device plays a "buffering" role between the power grid and the electrical equipment, reducing the impact of high-power output on the power grid.

[0123] In some embodiments, each energy storage unit includes a battery sub-unit, and the ratio between the rated energy of the battery sub-unit and the rated charging output power of the charging module is greater than or equal to 1 / (n2*n3), where n2 is in the range of 94% to 99%, and n3 is in the range of 4 to 6.

[0124] In some embodiments, each energy storage unit includes a battery sub-unit, and the ratio between the rated energy of the battery sub-unit and the rated power of the battery sub-unit is less than or equal to 1 / 3, and / or the volumetric energy density of the battery sub-unit is greater than or equal to 380 Wh / L.

[0125] Thus, while ensuring charging performance, the reliability of the charging device is also considered. When the rated energy of the battery sub-unit is adapted to the rated charging output power of the charging module, the battery sub-unit can stably provide energy for the charging module during the charging process, reducing the instability or interruption of the charging power caused by insufficient energy supply. Taking n2=94% and n3=6 as an example, the larger denominator requires the battery sub-unit to have a relatively high rated energy to match the power of the charging module. This allows the charging device to work continuously and stably during long-time and high-power charging, reduces the probability of failure, and reduces maintenance costs, thereby improving the performance-cost ratio in terms of the service life of the charging device.

[0126] In some embodiments, one or more energy storage units are connected in series and / or parallel between the second positive power supply end and the second negative power supply end of the energy storage module through the first positive power supply end and the first negative power supply end to provide the first direct current.

[0127] In some embodiments, each energy storage unit includes a battery sub-unit, the battery sub-unit includes a single battery cell, the single battery cell includes an electrolyte, the electrolyte includes an electrolyte salt, the electrolyte salt includes lithium hexafluorophosphate, and the concentration of the lithium hexafluorophosphate is in the range of 0.5 mol / L to 1.0 mol / L.

[0128] By setting the electrolyte to include lithium hexafluorophosphate at the above concentration, the battery subunit has a high ionic conductivity, thereby improving the charging rate of the charging device, and also has a high interface stability and a high thermal stability; lithium hexafluorophosphate has a small influence on the severity of thermal runaway, so that the battery subunit has a suitable severity of thermal runaway and a low risk of thermal diffusion, thereby making the charging device have a high reliability when the power output is above 350 kW.

[0129] In some embodiments, the electrolyte further includes an organic solvent, and the organic solvent includes a carbonate-based solvent.

[0130] Adding the carbonate-based solvent to the electrolyte can improve various performances of the battery subunit, for example, the charging and discharging efficiency, the cycle performance, the low-temperature performance, and the high-voltage stability of the battery subunit.

[0131] In some embodiments, the electrolyte salt further includes a fluorine-containing sulfonimide salt, and the concentration of the fluorine-containing sulfonimide salt is in a range from 0.2 mol / L to 0.5 mol / L.

[0132] Since the fluorine-containing sulfonimide salt has a low viscosity and a high ionic conductivity, the electrolyte including the fluorine-containing sulfonimide salt at the above concentration is conducive to improving the charging rate of the battery subunit, thereby improving the charging rate of the charging device.

[0133] In some embodiments, the electrolyte further includes an organic solvent, and the organic solvent includes a chain carboxylic acid ester-based solvent, and the mass content A of the chain carboxylic acid ester-based solvent based on the total mass of the solvent satisfies: 5%≤A≤75%,

[0134] The chain carboxylic acid ester-based solvent includes a compound having the following structure:

[0135]

[0136] R1 includes at least one of a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 haloalkyl group, and R2 includes a C1-C5 alkyl group and / or a C1-C5 haloalkyl group.

[0137] In this technical solution, the solvent includes the carboxylic acid ester-based solvent, so that the electrolyte can have a higher ionic conductivity and a relatively lower viscosity, which is conducive to further improving the rapid charging performance, such as the fast charging performance and / or the super charging performance, of the charging device.

[0138] In some embodiments, 40%≤A≤75%.

[0139] Setting A to be greater than or equal to 40% and less than or equal to 75% can better achieve the purpose of rapid charging of the charging device.

[0140] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a single cell, the single cell comprises a negative pole tab, the negative pole tab comprises a negative pole current collector and a negative pole film layer arranged on at least one side of the negative pole current collector, the negative pole film layer comprises a negative pole active material, and the negative pole active material comprises a carbon-based material, the carbon-based material comprises at least one of natural graphite and artificial graphite.

[0141] The carbon-based material using at least one of natural graphite and artificial graphite as the negative pole active material has good electrical conductivity and high theoretical specific capacity. The natural graphite has high crystallinity and regular layered structure, which is beneficial to the fast embedding and extraction of lithium ions, thereby improving the charging and discharging efficiency of the battery. The artificial graphite can accurately adjust its microstructure and performance by controlling the production process, thereby enhancing the cycle stability of the battery and prolonging the service life of the battery.

[0142] In some embodiments, the volume average particle size Dv50 of the negative pole film layer is in the range of 8.2 μm-13.5 μm.

[0143] Therefore, this particle size range can balance the specific surface area and the compaction density. Smaller particle size can provide larger specific surface area, increase the reaction sites of lithium ions, and improve the charging and discharging rate performance of the battery. Appropriate particle size can ensure higher compaction density, reduce the voids between active materials, and improve the energy density of the battery, thereby achieving a good balance between the rate performance and the energy density of the battery.

[0144] In some embodiments, the negative pole film layer comprises a first negative pole active material layer and a second negative pole active material layer arranged in a stack, the first negative pole active material layer is located on the side close to the negative pole current collector, the volume average particle size Dv50 of the negative pole active material in the first negative pole active material layer is in the range of 9.5 μm-18.5 μm, and the volume average particle size Dv50 of the negative pole active material in the second negative pole active material layer is in the range of 7.8 μm-14.3 μm.

[0145] When the volume average particle size Dv50 of the negative pole active material in the first negative pole active material layer and the volume average particle size Dv50 of the negative pole active material in the second negative pole active material layer are in the above range, on the one hand, the solid-phase transmission path of lithium ions can be shortened, and the fast charging performance can be improved, and on the other hand, the material is not prone to agglomeration during the preparation process, and the stability of the material can be improved. The negative pole active material in the second negative pole active material layer and the negative pole active material in the first negative pole active material layer in the above volume average particle size range cooperate to facilitate the construction of the gradient pore difference between the second negative pole active material layer and the first negative pole active material layer, reduce the tortuosity of lithium ion transmission, and improve the fast charging performance of the battery single cell.

[0146] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a single battery cell, the single battery cell comprises a negative electrode tab, the negative electrode tab comprises a negative electrode current collector and at least one negative electrode film layer located on one side of the negative electrode current collector, the negative electrode film layer comprises a negative electrode active material layer.

[0147] The compaction density of the negative electrode film layer is 1.15 g / cm 3 -1.36 g / cm 3 , and / or the single-side coating weight of the negative electrode film layer is 0.09 g / 15 40.25 mm 2 -0.17 g / 15 40.25 mm 2 .

[0148] When the compaction density of the negative electrode film layer is in the above range, the energy density of the battery cell can be improved, and because the negative electrode active material in the negative electrode film layer is packed more closely, the contact resistance between particles is smaller, which can further reduce the resistance of the tab and thus reduce heat generation.

[0149] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a single battery cell, the single battery cell comprises a positive electrode tab, the positive electrode tab comprises a positive electrode current collector and at least one positive electrode film layer located on one side of the positive electrode current collector, the positive electrode film layer comprises a positive electrode active material layer;

[0150] The compaction density of the positive electrode film layer is 2.5 g / cm 3 -2.8 g / cm 3 .

[0151] When the compaction density of the positive electrode film layer is in the above range, the energy density of the battery cell can be improved, and because the positive electrode active material in the positive electrode film layer is packed more closely, the contact resistance between particles is smaller, which can further reduce the resistance of the tab and thus reduce heat generation.

[0152] In some embodiments, the single-side coating weight of the positive electrode film layer is 0.2 g / 15 40.25 mm 2 -0.37 g / 15 40.25 mm 2 .

[0153] When the single-side coating weight of the positive electrode film layer is in the above range, the heat generation per unit area of the positive electrode tab will not be too large, and the energy density of the battery cell can be improved.

[0154] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a single battery cell, the single battery cell comprises a positive electrode sheet, the positive electrode sheet comprises a positive electrode current collector and at least one positive electrode film layer located on one side of the positive electrode current collector, and the thickness of the positive electrode current collector is 10-15 microns.

[0155] When the thickness of the positive electrode current collector is in the above range, the overcurrent capacity of the positive electrode current collector is excellent, and the battery cell can have a higher energy density.

[0156] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a single battery cell, the single battery cell comprises a separator film, the separator film comprises a base film with a porous structure, and the porosity of the base film is 20-70%.

[0157] When the porosity of the base film is in the above range, the migration ability of lithium ions in the separator film can be improved, and the internal resistance of the battery cell can be reduced, thereby reducing heat generation.

[0158] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a positive electrode sheet, the positive electrode sheet comprises a positive electrode current collector and at least one positive electrode film layer located on one side of the positive electrode current collector, and the positive electrode film layer comprises a positive electrode active material, and the positive electrode active material comprises a lithium-containing phosphate.

[0159] The lithium-containing phosphate comprises phosphate particles and a coating layer, the coating layer is coated on at least part of the surface of the phosphate particles, and the coating layer comprises one or more elements selected from C, Fe, Ti, Zr, Hf, Ge, and Sn.

[0160] In this technical solution, the positive electrode coating layer has excellent ion and electron conductivity, which can improve the ion and electron conductivity of the positive electrode active material, thereby effectively improving the charge rate of the battery subunit and the rapid charging performance of the charging device, and is beneficial to improving the rapid charging performance of the battery device.

[0161] In some embodiments, the coating layer comprises a fast ion conductor, and the fast ion conductor comprises a compound with a general formula of Li 3-d Fe 2- d M 2d (PO4)3, M2 comprises at least one element selected from Ti, Zr, Hf, Ge, and Sn, and 0≤d≤1.

[0162] Since the fast ion conductor has high ion conductivity, it is beneficial to the diffusion and transmission of lithium ions, and thus the charge rate of the battery subunit and the rapid charging performance of the charging device can be further improved, which is beneficial to improving the rapid charging performance of the battery device.

[0163] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a positive electrode sheet, the positive electrode sheet comprises a positive electrode current collector, a positive electrode conductive layer and a positive electrode film layer, the positive electrode film layer is arranged on at least one side of the positive electrode current collector, the positive electrode conductive layer is located between the positive electrode current collector and the positive electrode film layer, and the thickness of the positive electrode conductive layer is in the range of 0.5-2 microns.

[0164] In this way, the diffusion path of lithium ions can be shortened, thereby improving the rate performance of the battery subunit and facilitating the improvement of the rapid charging performance of the battery device.

[0165] In some embodiments, the positive electrode conductive layer comprises a positive electrode conductive agent, and the mass content of the positive electrode conductive agent is in the range of 30%-50% based on the total mass of the positive electrode conductive layer.

[0166] The mass content of the positive electrode conductive agent is set in the range of 30%-50%, which can improve the electron transmission efficiency in the positive electrode sheet and further improve the rate performance of the battery subunit.

[0167] In some embodiments, the positive electrode conductive layer comprises a positive electrode binder, and the mass content of the positive electrode binder is in the range of 50%-70% based on the total mass of the positive electrode conductive layer.

[0168] The mass content of the positive electrode binder is set in the range of 50%-70%, which can reduce the possibility of cracking or peeling of the positive electrode sheet during the cycle process, and further improve the cycle life of the battery subunit.

[0169] In some embodiments, each energy storage unit comprises a battery subunit, the battery subunit comprises a positive electrode sheet, the positive electrode sheet comprises a positive electrode current collector, a positive electrode conductive layer and a positive electrode film layer, the positive electrode film layer is arranged on at least one side of the positive electrode current collector, the positive electrode conductive layer is located between the positive electrode current collector and the positive electrode film layer, and the thickness of the positive electrode conductive layer is in the range of 0.5-2 microns.

[0170] In this way, the diffusion path of lithium ions can be shortened, thereby improving the rate performance of the battery subunit and facilitating the improvement of the rapid charging performance of the battery device.

[0171] In some embodiments, the negative electrode conductive layer comprises a negative electrode conductive agent, and the mass content of the negative electrode conductive agent is in the range of 20%-40% based on the total mass of the negative electrode conductive layer.

[0172] The mass content of the negative electrode conductive agent is set in the range of 20%-40%, which can improve the electron transmission efficiency in the negative electrode sheet and further improve the rate performance of the battery subunit and facilitate the improvement of the rapid charging performance of the battery device.

[0173] In some embodiments, the negative electrode conductive layer comprises a negative electrode binder, and the mass content of the negative electrode binder is in a range from 60% to 80% based on the total mass of the negative electrode conductive layer.

[0174] The technical solution sets the mass content of the negative electrode binder in a range from 60% to 80%, which can reduce the possibility of cracking or peeling of the negative electrode sheet during the cycle process, thereby improving the cycle life of the battery subunit and being beneficial to improving the cycle life of the battery device.

[0175] In another aspect, an embodiment of the present application provides a computer readable storage medium having a computer program stored thereon, the computer program being executed by a controller to implement some or all of the steps in the above method.

[0176] In another aspect, an embodiment of the present application provides a computer program product comprising a computer program or instructions, the computer program or instructions being executed by a controller to implement some or all of the steps in the above method.

[0177] It should be understood that the above general description and the following detailed description are only exemplary and explanatory, but not limiting the technical solutions of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0178] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments, and are not meant to limit the present application. Moreover, the same reference numerals in the attached drawings indicate the same or similar elements. In the drawings:

[0179] Figure 1 Structure schematic diagram of a charging device of a series connection of energy storage units according to an embodiment of the present application.

[0180] Figure 2 Structure schematic diagram of a charging device with an input module according to an embodiment of the present application.

[0181] Figure 3 Structure schematic diagram of a charging device of a parallel connection of energy storage units according to an embodiment of the present application.

[0182] Figure 4a Structure schematic diagram of a charging device of an energy storage unit comprising a battery subunit according to an embodiment of the present application.

[0183] Figure 4b Structure schematic diagram of a charging device of an energy storage unit comprising a battery subunit and a first power conversion subunit according to an embodiment of the present application.

[0184] Figure 4cThis is a schematic structural diagram of a charging device in which an energy storage unit according to an embodiment of the present application includes a battery subunit and a first switch subunit.

[0185] Figure 4d This is a structural diagram of a charging device in which an energy storage unit according to an embodiment of the present application includes a battery subunit, a first power conversion subunit and a first switch subunit.

[0186] Figure 5a This is a structural diagram of a charging device including an input interface in an input module according to an embodiment of the present application.

[0187] Figure 5b This is a structural diagram of a charging device in which an input module according to an embodiment of the present application includes a second power conversion sub-unit.

[0188] Figure 6a This is a schematic structural diagram of a charging device in which charging guns do not share a common load according to an embodiment of the present application.

[0189] Figure 6b This is a schematic structural diagram of a charging device for charging guns sharing a common load according to an embodiment of the present application.

[0190] Figure 7 Schematic diagram of the structure of a charging device with a selection unit according to an embodiment of the present application.

[0191] Figure 8 for Figure 7 A schematic structural diagram of a charging device having a second positive power supply terminal is shown.

[0192] Figure 9a for Figure 8 The diagram shows the structure of a charging device with a second positive power supply terminal and charging guns that do not share a negative connection.

[0193] Figure 9b for Figure 8 The diagram shows the structure of a charging device with a second positive power supply terminal and a common negative charging terminal for charging guns.

[0194] Figure 10 for Figure 7 A schematic structural diagram of a charging device having multiple second positive power supply terminals is shown.

[0195] Figure 11a for Figure 10 The diagram shows the structure of a charging device with multiple second positive power supply terminals and charging guns that do not share a common negative terminal.

[0196] Figure 11b for Figure 10 The diagram shows the structure of a charging device with multiple second positive power terminals and a common negative charging gun.

[0197] Figure 12a Figure 1 shows a structural schematic diagram of a charging device according to an embodiment of the present application. Figure 7 Figure 2 shows a structural schematic diagram of a charging device having a selection unit and an input module including a first power conversion subunit according to an embodiment of the present application.

[0198] Figure 12b Figure 3 shows a structural schematic diagram of a charging device having a selection unit and an input module including a plurality of second power conversion subunits according to an embodiment of the present application. Figure 7

[0199] Figure 13 Figure 4 shows a structural schematic diagram of a charging device having a wireless communication module according to an embodiment of the present application.

[0200] Figure 14 Figure 5 shows a structural schematic diagram of a charging device having energy storage units connected in series, each energy storage unit including a bidirectional DCDC subunit, and the charging gun not sharing a negative pole according to an embodiment of the present application.

[0201] Figure 15 Figure 6 shows a structural schematic diagram of a charging device having energy storage units connected in series, each energy storage unit including a bidirectional DCDC subunit, and the charging gun sharing a negative pole according to an embodiment of the present application.

[0202] Figure 16 Figure 7 shows a structural schematic diagram of a charging device having energy storage units connected in parallel, each energy storage unit including a bidirectional DCDC subunit, and the charging gun not sharing a negative pole according to an embodiment of the present application.

[0203] Figure 17 Figure 8 shows a structural schematic diagram of a charging device having energy storage units connected in parallel, each energy storage unit including a bidirectional DCDC subunit, and the charging gun sharing a negative pole according to an embodiment of the present application.

[0204] Figure 18 Figure 9 shows a structural schematic diagram of a charging device having energy storage units connected in series, part of the energy storage units including a bidirectional DCDC subunit, and the charging gun not sharing a negative pole according to an embodiment of the present application.

[0205] Figure 19 Figure 10 shows a structural schematic diagram of a charging device having energy storage units connected in series, part of the energy storage units including a bidirectional DCDC subunit, and the charging gun sharing a negative pole according to an embodiment of the present application.

[0206] Figure 20 Figure 11 shows a structural schematic diagram of a charging device having energy storage units connected in parallel, each energy storage unit including a first switch subunit, and the charging gun not sharing a negative pole according to an embodiment of the present application.

[0207] Figure 21 Figure 12 shows a structural schematic diagram of a charging device having energy storage units and bidirectional ACDC subunits constituting three-phase electricity, and the charging gun not sharing a negative pole according to an embodiment of the present application.

[0208] Figure 22 ​Structure diagram of a charging device with a three-phase power supply and a charging gun shared by a charging unit and a bidirectional AC-DC subunit according to an embodiment of the present application.

[0209] Figure 23 Structure diagram of a single battery cell according to some embodiments of the present application.

[0210] Figure 24 Structure diagram of a single battery cell according to some embodiments of the present application.

[0211] Figure 25 Structure diagram of a battery module according to some embodiments of the present application.

[0212] Figure 26 Structure diagram of a battery module according to some embodiments of the present application.

[0213] Figure 27 Structure diagram of a battery module according to some embodiments of the present application.

[0214] Figure 28 Structure diagram of a charging pile according to an embodiment of the present application.

[0215] Figure 29 Structure diagram of a charging and storing system according to an embodiment of the present application.

[0216] Figure 30 Structure diagram of a charging and storing system with multiple charging devices sharing a DC bus according to an embodiment of the present application.

[0217] Figure 31 Structure diagram of a charging and storing system with multiple charging devices sharing a DC bus according to another embodiment of the present application.

[0218] Figure 32 Structure diagram of a charging and storing system with multiple charging devices sharing an AC bus according to an embodiment of the present application.

[0219] Figure 33 Composition structure of a charging system according to an embodiment of the present application Figure 1 .

[0220] Figure 34 Composition structure of a charging system according to an embodiment of the present application Figure 2 .

[0221] Figure 35 Implementation flowchart of a charging method according to an embodiment of the present application Figure 1 .

[0222] Figure 36 Implementation flowchart of a charging method according to an embodiment of the present application Figure 2 .

[0223] Figure 37 An implementation flow of a charging method of an electric vehicle and a battery system module is provided for the embodiment of the present application.

[0224] Figure 38A A charging mode diagram of a single battery system power supply is provided for the embodiment of the present application.

[0225] Figure 38B A communication architecture diagram of a charging system is provided for the embodiment of the present application.

[0226] Figure 38C A charging mode diagram of a power grid supplying energy to a battery system module is provided for the embodiment of the present application.

[0227] Figure 38D A charging mode diagram of a power grid supplying energy to a battery system module is provided for the embodiment of the present application.

[0228] Figure 38E A charging mode diagram of a single battery system power supply is provided for the embodiment of the present application.

[0229] Figure 39 An implementation flow of a charging method of an electric vehicle and a battery system module is provided for the embodiment of the present application.

[0230] Figure 40A A charging mode diagram of a power grid supplying energy to a battery system module is provided for the embodiment of the present application.

[0231] Figure 40B A charging mode diagram of a power grid supplying energy to a battery system module is provided for the embodiment of the present application.

[0232] Figure 41A A charging control device is provided for the embodiment of the present application. Figure 1 .

[0233] Figure 41B A charging control device is provided for the embodiment of the present application. Figure 2 .

[0234] Figure 41C A charging control device is provided for the embodiment of the present application. Figure 3 .

[0235] Figure 41D A charging control device is provided for the embodiment of the present application.

[0236] Figure 41EFigure 5 is a schematic diagram of a charging control device according to an embodiment of the present application.

[0237] Figure 41F Figure 6 is a schematic diagram of a charging control device according to an embodiment of the present application.

[0238] Figure 41G Figure 7 is a schematic diagram of a charging control device according to an embodiment of the present application. Figure 7 .

[0239] The following reference signs are used in the description:

[0240] 100, charging device; 110, energy storage module; 120, charging module; 121, third power conversion subunit; 122, charging gun; 123, fourth power conversion subunit; 124, fifth power conversion subunit; 125, sixth power conversion subunit; 130, input module; 140, wireless communication module; 111, selection unit; 210, first external power supply; 220, second external power supply; 131, second power conversion subunit; 132, ninth power conversion subunit;

[0241] 1, electric device; 2, battery pack; 3, controller; 4, motor; 5, box body; 5a, first box body part; 5b, second box body part; 5c, containing space; 6, battery module;

[0242] 7, single cell;

[0243] 10, electrode assembly; 11, first tab; 13, second tab; 12, main body part;

[0244] 20, shell; 21, housing; 22, end cover;

[0245] 31, first electrode terminal; 32, second electrode terminal. DETAILED DESCRIPTION

[0246] The embodiments of the technical solutions of the present application will be described in detail below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solutions of the present application, and therefore only serve as examples, and cannot limit the protection scope of the present application.

[0247] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terms used herein are only for the purpose of describing specific embodiments and are not intended to limit the present application; the terms "include" and "have" and any variations thereof in the specification and claims of the present application and the above description of drawings are intended to cover non-exclusive inclusion.

[0248] In the description of the embodiments of the present application, the technical terms "first", "second", etc. are only used to distinguish different objects, and cannot be understood as indicating or implying relative importance or implicitly indicating the number, specific order or primary and secondary relationship of the indicated technical features. In the description of the embodiments of the present application, the meaning of "multiple" is more than two, unless otherwise explicitly specified and limited.

[0249] Reference herein to "embodiments" means that the particular features, structures, or characteristics described in connection with the embodiments can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily all refer to the same embodiment, nor is it necessarily a separate or alternative embodiment to other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0250] In the description of the embodiments of the present application, the term "and / or" is only a description of the association relationship of the associated objects, which means that there can be three relationships, for example, A and / or B, which can represent the three cases of A alone, A and B together, and B alone. In addition, the character " / " herein generally represents an "or" relationship between the front and rear associated objects.

[0251] In the description of the embodiments of the present application, the term "multiple" refers to more than two (including two), and similarly, "multiple groups" refers to more than two groups (including two groups), and "multiple pieces" refers to more than two pieces (including two pieces).

[0252] In the description of the embodiments of the present application, the technical terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the embodiments of the present application and simplifying the description, and therefore cannot be understood as indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the embodiments of the present application.

[0253] In the description of the embodiments of the present application, unless otherwise explicitly specified and limited, the technical terms "mounting", "connection", "connection", "fixing" and the like should be understood in a broad sense, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication of two elements or the interaction relationship between two elements. For those skilled in the art, the specific meaning of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0254] At present, with the rapid increase of electric equipment, the slow charging of electric equipment, poor experience and other problems need to be solved. In order to meet the charging demand of electric equipment in different scenes, various charging modes appear, but there is no good method to determine the appropriate charging mode for electric equipment charging.

[0255] Based on this, the application provides a charging method, including: in response to a charging event, determining charging demand information of electric equipment; based on the charging demand information, determining a target charging mode of a charging device for charging the electric equipment, wherein the target charging mode corresponds to target charging parameters; the charging device includes an energy storage device; based on the target charging parameters corresponding to the target charging mode, charging the electric equipment; wherein, in the case that the target charging mode includes a first charging mode, the target charging parameters corresponding to the first charging mode include a first charging parameter, and the first charging parameter indicates a charging power greater than 300 kilowatts. Based on the charging demand information of the electric equipment, the target charging mode of the charging device for charging the electric equipment is determined, and then the electric equipment is charged based on the target charging parameters corresponding to the target charging mode. Through this method, in the case that there are multiple charging modes, the most suitable charging mode for the electric equipment can be determined based on the charging demand information of the electric equipment.

[0256] The charging device disclosed in the embodiments of the application can be used to charge electric vehicles, electric ships, electric tools and other devices that require fast charging / ultra-fast charging, and can also be used to charge electric vehicles, electric ships, electric tools and other devices that do not require fast charging / ultra-fast charging. That is, the charging device disclosed in the embodiments of the application can realize charging of electric equipment according to high power and low power, and has wide application range.

[0257] The charging and storage system of the application will be described below in conjunction with specific embodiments.

[0258] Figure 1 The structure diagram of the charging device 100 according to an embodiment of the application is shown.

[0259] Referring to Figure 1 , the charging device 100 can include an energy storage module 110 and a charging module 120.

[0260] The energy storage module 110 includes one or more energy storage units, which are energy storage unit A1,..., energy storage unit A n-1 and energy storage unit A n(n is a positive integer), each energy storage unit has a first positive power supply end (+) and a first negative power supply end (-), one or more energy storage units are connected to the second positive power supply end (+) and the second negative power supply end (-) of the energy storage module 110 through the first positive power supply end and the first negative power supply end, and the energy storage module 110 is configured to provide a first direct current. As an example, the energy storage unit can be an electric box.

[0261] The charging module 120 is connected to the second positive power supply end and the second negative power supply end of the energy storage module 110, and the charging module 120 is configured to be suitable for charging output based on the first direct current. The maximum charging output power of the charging module 120 is greater than or equal to 350 kilowatts, and / or the rated charging output power of the charging module 120 is greater than or equal to 290 kilowatts.

[0262] Specifically, the number of energy storage units can be selected and set based on actual needs. When the charging device 100 is only used for small power charging, the energy storage unit can be set to one or a small number of several, which can meet the small power charging application scenario at this time; when the charging device 100 is used for large power charging, the energy storage unit can be set to multiple, which can meet the large power and small power charging application scenario, for example, adjusting the charging output power of the energy storage unit, the charging module or the energy storage unit and the charging module can be used for large power or small power charging. Due to the modularity of the energy storage unit, the energy storage unit can be freely increased or decreased, which can realize quick access and large power charging without the need to increase or expand the transformer.

[0263] When the energy storage unit is one, the first positive power supply end of the energy storage unit is connected to the second positive power supply end of the energy storage module 110, and the first negative power supply end of the energy storage unit is connected to the second negative power supply end of the energy storage module 110. The second positive power supply end and the second negative power supply end of the energy storage module 110 are also connected to the charging module 120. When charging, the energy storage module 110 provides the first direct current through the energy storage unit, and the charging module 120 converts the first direct current to obtain the target direct current to charge the device to be charged. At this time, the charging device 100 can meet the small power charging application scenario. It should be noted that the related parameters of the energy storage unit and the charging module 120 can be set based on actual conditions, and the charging demand can be met through reasonable parameter configuration.

[0264] When the energy storage unit is multiple, multiple energy storage units can be connected in series, parallel or series-parallel mode, and connected to the charging module 120 through the second positive power supply end and the second negative power supply end of the energy storage module 110. For example, in the case of multiple energy storage units, the energy storage units are connected in series, and the series connection of the energy storage units is connected to the second positive power supply end and the second negative power supply end of the energy storage module 110. Figure 1In the specific embodiment, the energy storage unit A1, the energy storage unit An-1 and the energy storage unit An are connected in series between the second positive power supply end and the second negative power supply end of the energy storage module 110 through the first positive power supply end and the first negative power supply end of each energy storage unit, and the second positive power supply end and the second negative power supply end of the energy storage module 110 are also connected with the charging module 120. When charging, when high-power charging is needed, the energy storage module 110 provides the first direct current through the plurality of energy storage units, and the first direct current can have a high power, and then the charging module 120 converts the first direct current to obtain the target direct current for charging the device to be charged, and the target direct current has a high power, so as to meet the high-power charging application scenario; when low-power charging is needed, the first direct current can have a low power, and the target direct current has a low power, so as to meet the low-power charging application scenario. It should be noted that the related parameters of the energy storage unit and the charging module 120 can be set based on the actual situation, and the charging demand can be met through reasonable parameter configuration. When there are a plurality of energy storage units, the power of the energy storage module is the sum of the powers of the plurality of energy storage units.

[0265] For example, the maximum charging output power of the charging module 120 is greater than or equal to 350 kW, that is, the maximum charging output power of the charging device 100 is greater than or equal to 350 kW. For example, by selecting a proper number of energy storage units, the maximum charging output power of the charging module 120 can reach 350 kW, 360 kW, 500 kW, 800 kW, 900 kW, etc. It should be noted that the charging output power here refers to the maximum charging output power, and in actual charging, it can be downward compatible, for example, when the maximum charging output power is 360 kW, it means that the charging device 100 can output a charging output power of 0-360 kW to meet different charging demands.

[0266] It can be understood that the maximum charging output power of the charging module 120 and the rated charging output power satisfy a certain multiple relationship, for example, a multiple relationship of 1.1-1.2, so the rated charging output power of the charging module 120 can be greater than or equal to 290 kW, that is, the rated charging output power of the charging device 100 is greater than or equal to 290 kW.

[0267] In actual application, the maximum charging output power of the charging module 120 can be limited, the rated charging output power can be limited, or both can be limited.

[0268] In the above embodiments, by configuring the modular energy storage units inside the charging device, or by arranging the modular energy storage units and the modular charging units outside the charging device, i.e., arranging the energy storage modules and the charging modules outside the charging device, the energy storage units and the charging units can be freely added or removed. When high-power charging is needed, the free and fast access of the energy storage units can not only realize high-power charging, such as fast charging / ultra-fast charging, but also can reduce the cost of transformers without the need of additional transformers or transformer expansion.

[0269] In some embodiments, referring to Figure 2 The charging device 100 further includes an input module 130 adapted to provide charging energy for each energy storage unit.

[0270] In an example, the input module 130 can be an AC-DC conversion unit.

[0271] Taking the input module 130 as an AC-DC conversion unit as an example, the input module 130 can be adapted to provide charging energy for the energy storage units. In different power consumption environments, whether in old urban areas with relatively tight power supply or in remote areas sensitive to infrastructure construction cost, the charging device can adjust the power supply parameters of the energy storage modules 110 by the input module 130, so as to realize the function of fast charging without relying on external complex power supply upgrade, and enhance the applicability and flexibility of the charging device in various scenarios.

[0272] Therefore, the power grid can charge the energy storage units through the input module 130.

[0273] In some embodiments, the maximum output power of the input module 130 is less than or equal to 150 kilowatts, and / or the rated output power of the input module 130 is less than or equal to 125 kilowatts.

[0274] Specifically, the input module 130 is mainly used for charging each energy storage unit in the energy storage module 110, and is used for small-power charging during charging. For example, the maximum output power of the input module 130 is less than or equal to 150 kilowatts, such as 150 kilowatts, 100 kilowatts, 85 kilowatts, etc. It should be noted that the output power here refers to the maximum output power, which can be downward compatible during actual charging. For example, when the maximum output power is 150 kilowatts, it means that the output power of 0-150 kilowatts can be used to charge each energy storage unit in the energy storage module 110.

[0275] In this example, the input module 130 is for small power output, while the charging module 120 can be for large power output, so the entire charging device 100 can achieve large power output under small power input. For example, the input end of the transformer is connected to the AC power grid, and the output end of the transformer is connected to the input module 130. When the transformer is a small-capacity transformer, the maximum output power of the input module 130 will also be limited due to the capacity of the transformer, such as a maximum output power of 150 kW. At this time, the small power is used to charge each energy storage unit in the energy storage module 110, but when the energy storage module 110 discharges externally to charge the device to be charged, based on multiple energy storage units, large power charging can be achieved, such as a maximum charging output power of 360 kW of the charging module 120. In this way, large power output under small power input is achieved, so that the charging device can meet the demand for large power charging without additional transformers or transformer expansion. Those skilled in the art can understand that the power grid generally refers to a system that can provide power. As an example, the power grid can be a municipal power source.

[0276] It can be understood that the maximum output power of the input module 130 and the rated output power satisfy a certain multiple relationship, for example, a multiple relationship of 1.1-1.2, so the rated output power of the input module 130 can be less than or equal to 125 kW.

[0277] In actual application, the maximum output power of the input module 130 can be limited, the rated output power can be limited, or both can be limited.

[0278] In the above embodiment, by configuring modular energy storage units inside the charging device 100, the maximum output power and / or rated power of the input module 130 is limited within the above range, so that the charging device 100 can be flexibly connected to the power network. Specifically, since the output power of most public power grids or commercial power interfaces has certain limitations, the power setting of the input module 130 can successfully obtain charging energy from the conventional power environment without modifying the existing power supply line, improving the accessibility of the charging device 100 in various power consumption scenarios to facilitate the installation of the charging device 100. In addition, the charging device 100 can achieve large power charging under small power input, so that the charging device 100 can meet the demand for large power charging without additional transformers or transformer expansion. During the peak power consumption period, when multiple power consumption devices are running at the same time, the energy storage module supplies power to multiple power consumption devices, and the input module 130 charges the energy storage unit at a lower power, which can effectively reduce the impact of the charging device 100 on the power grid during charging, and help maintain the stability of the power grid.

[0279] In some embodiments, the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 is greater than 1 and less than or equal to 15, and / or the ratio between the rated charging output power of the charging module 120 and the rated output power of the input module 130 is greater than 1 and less than or equal to 15.

[0280] Specifically, the maximum charging output power of the charging module 120 is greater than the maximum output power of the input module 130, i.e., the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 is greater than 1, for example, the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 can be greater than 2, greater than 2.3, greater than 3, greater than 4, greater than 8, or greater than 12.5, etc., so as to realize high-power output under low-power input. For example, when the ratio is 12.5, it means that the maximum charging output power of the charging module 120 is 12.5 times the maximum output power of the input module 130, assuming that the maximum output power of the input module 130 is 40 kW, then the maximum charging output power of the charging module 120 is greater than or equal to 500 kW.

[0281] Meanwhile, the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 is less than or equal to 15, for example, it can be 15, 12.5, 10.3, 9, 7, and 6, etc. For example, when the ratio is 6, it means that the maximum charging output power of the charging module 120 is 6 times the maximum output power of the input module 130, assuming that the maximum output power of the input module 130 is 150 kW, then the maximum charging output power of the charging module 120 is less than or equal to 900 kW.

[0282] It should be noted that when the above ratio is set, the minimum ratio is less than or equal to the maximum ratio, for example, the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 is greater than 2 and less than or equal to 15, or greater than 1 and less than or equal to 6, or greater than 6 and less than or equal to 12.5, etc., which is selected according to actual needs.

[0283] In this way, by limiting the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130, high performance and cost ratio can be achieved under the condition of high-power output under low-power input.

[0284] It can be understood that the maximum charging output power of the charging module 120 and the rated charging output power satisfy a certain multiple relationship, for example, a multiple relationship of 1.1-1.2, and the maximum output power of the input module 130 and the rated output power satisfy a certain multiple relationship, for example, a multiple relationship of 1.1-1.2, so the ratio between the rated charging output power of the charging module 120 and the rated output power of the input module 130 can also be greater than 1 and less than or equal to 15.

[0285] In actual application, the ratio between the maximum charging output power of the charging module 120 and the maximum output power of the input module 130 can be limited, the ratio between the rated charging output power of the charging module 120 and the rated output power of the input module 130 can be limited, or both can be limited.

[0286] In the above embodiment, by limiting the ratio between the maximum charging output power of the charging module and the maximum output power of the input module, and / or limiting the ratio between the rated charging output power of the charging module and the rated output power of the input module, on the one hand, the current impact and overheating problems caused by the charging module 120 due to instantaneous excessive power input can be reduced. On the other hand, the input module 130 can charge the energy storage module 110 with small power, and the energy storage module can output to the charging module 120 with controllable large power, realizing small power input to the energy storage module 110 and large power output of the charging module 120. In addition, the energy storage module 110 can flexibly adjust the output power according to the amount of electricity stored and the power demand of the power consumption equipment, so that the charging device 100 can reasonably distribute the electric energy, reduce unnecessary energy consumption, improve the performance-price ratio of the charging device 100, and make the charging device 100 run smoothly when small power input and large power output.

[0287] In some embodiments, each energy storage unit includes a battery subunit, and the ratio between the rated output power of the input module 130 and the rated energy of the battery subunit is greater than or equal to 1 / n1, where n1 is in the range of 1-4.

[0288] Specifically, the rated energy of the battery subunit refers to the energy capacity specified at the design of the battery subunit, which represents the maximum energy value that the battery subunit can store or output under normal working conditions, and the unit is kilowatt-hour. The rated output power of the input module 130 is greater than or equal to the rated energy of the battery subunit / n1 / 100%, where n1 can be 1, 1.4, 2, 3, and 4, etc. By specifying that the rated output power of the input module is greater than the rated energy of the battery subunit divided by the coefficient n1, when the input power of the input module 130 is small, the rated energy of the battery subunit is small, so that the input power and the rated energy of the battery subunit are matched, and the input module 130 will not charge the battery subunit too slowly, affecting the use of the energy storage unit. At the same time, the small rated energy of the battery subunit also means that the battery subunit has a small volume, so that the energy storage unit occupies a small area and is easy to install. Further, the small volume of the energy storage unit realizes small power input and large power output, and improves the user experience.

[0289] In some embodiments, each energy storage unit includes a battery subunit, and the ratio between the rated energy of the battery subunit and the rated charging output power of the charging module 120 is greater than or equal to 1 / (n2*n3), where n2 ranges from 94% to 99%, and n3 ranges from 4 to 6.

[0290] That is, the rated energy of the battery subunit is greater than or equal to the rated charging output power of the charging module 120 / (n2*n3)*100%, where n2 can be 94%, 96%, 98.5%, and 99%, etc., and n3 can be 4, 5, 5.5, and 6, etc. In this way, the charging performance is guaranteed while the reliability of the charging device 100 is taken into account. When the rated energy of the battery subunit and the rated charging output power of the charging module 120 are matched, the battery subunit can stably provide energy for the charging module 120 during the charging process, reducing the instability or interruption of the charging power caused by insufficient energy supply. Taking n2=94% and n3=6 as an example, the larger denominator requires the battery subunit to have a relatively high rated energy to match the power of the charging module 120, which enables the charging device 100 to work stably and continuously during a long-time and high-power charging process, reduces the probability of failure, and reduces maintenance costs, thereby prolonging the service life of the charging device 100 and improving the cost performance.

[0291] In some embodiments, each energy storage unit includes a battery subunit, and the ratio between the rated energy of the battery subunit and the rated power of the battery subunit is less than or equal to 1 / 3, and / or the volumetric energy density of the battery subunit is greater than 380 watt-hours per liter.

[0292] That is, the ratio of the rated energy of the battery subunit to the rated power of the battery subunit is not greater than 1:3. For example, when the rated power of the battery subunit is 350 kW, the rated energy of the battery subunit is 58 kWh. In this way, the cost performance of the entire charging device can be improved.

[0293] The volumetric energy density of the battery subunit is greater than or equal to 380 Wh / L, for example, 380 Wh / L, 400 Wh / L, 600 Wh / L, or 900 Wh / L, etc. It can be understood that the higher the energy density of the battery subunit, the smaller the corresponding volume, thereby saving space and reducing construction costs, while providing high-power output.

[0294] When the charging device 100 has a high-power (the maximum charging output power of the charging module is greater than or equal to 350 kW) output, the ratio of the rated energy of the battery subunit to the rated power of the battery subunit is less than or equal to 1 / 3, and / or the volumetric energy density of the battery subunit is greater than 380 Wh / L, so that the rated energy of the battery subunit matches the rated power of the battery subunit, reduces the grid fluctuation caused by the need for grid power supply due to insufficient rated energy of the battery subunit caused by high-power output, and is beneficial to improve the reliability and stability of the charging device 100. When the charging device 100 has a high-power output, it can work stably and continuously, reduce the probability of failure, reduce maintenance costs, thereby prolonging the service life of the charging device 100 and improving the cost performance.

[0295] In some embodiments, each energy storage unit includes a battery subunit, and the maximum discharge rate of the battery subunit is greater than or equal to 4C, for example, greater than or equal to 5C, 6C, 7C, or 8C, etc. In this way, high-power output can be provided.

[0296] It should be noted that the above parameters can be stacked. For example, when the maximum charging output power of the charging module 120 is greater than or equal to 350 kW, the maximum output power of the battery subunit is greater than or equal to 350 kW, the rated power of the battery subunit is greater than or equal to 350 kW, the rated energy of the battery subunit is greater than or equal to 58 kWh, and the maximum discharge rate of the battery subunit is greater than or equal to 4C, the maximum output power of the input module 130 can be less than or equal to 150 kW.

[0297] It should be noted that the above-mentioned related parameters of the battery sub-unit are applicable to the energy storage unit and / or the energy storage module in some cases, that is, the above-mentioned parameters are applicable to the energy storage unit, the energy storage module and the battery sub-unit in some cases. For example, when the energy storage unit only includes a battery sub-unit, the related parameters of the battery sub-unit are the related parameters of the energy storage unit, and further, when the energy storage module 110 includes an energy storage unit, the related parameters of the battery sub-unit are the related parameters of the energy storage module 110; and the like.

[0298] It should be noted that the energy storage unit can include one or more battery sub-units, and the plurality of battery sub-units can be connected in series, in parallel or in series-parallel. Each battery sub-unit can be a single cell or a plurality of single cells connected in series, in parallel or in series-parallel. For example, the single cell can include 10-100, and 2-6 battery sub-units can be obtained by combining the single cells, and the 2-6 battery sub-units can be connected in series and / or in parallel, so that the energy storage unit can reach 80-150 kilowatt hours through the 2-6 battery sub-units. For example, 80 kilowatt hours can be obtained by combining 2 single cells; for example, 150 kilowatt hours can be obtained by combining 100 single cells; for example, 90 kilowatt hours can be obtained by combining 80 single cells; and the like.

[0299] In the above-mentioned embodiments, by limiting the proportional relationship of the rated energy and the rated power of the battery sub-unit, the rated output power of the input module and the rated charging output power of the charging module, the entire charging device can have a high cost performance.

[0300] In some embodiments, one or more energy storage units are connected in series and / or in parallel between the second positive power supply end and the second negative power supply end of the energy storage module 110 through the first positive power supply end and the first negative power supply end to provide the first direct current.

[0301] Specifically, when the energy storage unit is one, the first positive power supply end of the energy storage unit is connected to the second positive power supply end of the energy storage module 110, and the first negative power supply end of the energy storage unit is connected to the second negative power supply end of the energy storage module 110, and the first direct current is provided through the energy storage unit.

[0302] When the energy storage unit is a plurality, the plurality of energy storage units can be connected in series, in parallel or in series-parallel. For example, referring to Figure 1 , the plurality of energy storage units are connected in series between the second positive power supply end and the second negative power supply end of the energy storage module 110 through the first positive power supply end and the first negative power supply end of the energy storage units; for example, referring to Figure 3For example, the plurality of energy storage units are connected in series between the second positive power supply end and the second negative power supply end of the energy storage module 110. For another example, the plurality of energy storage units are connected in parallel between the second positive power supply end and the second negative power supply end of the energy storage module 110. For yet another example, the plurality of energy storage units are connected in series first and then in parallel, or connected in parallel first and then in series between the second positive power supply end and the second negative power supply end of the energy storage module 110. The first direct current is provided by the plurality of energy storage units connected in series, in parallel, or in series and in parallel. The connection mode can be selected based on actual conditions.

[0303] In the above embodiments, the plurality of energy storage units can be connected in series, in parallel, or in series and in parallel, and free access of the energy storage units can be achieved to meet different charging power requirements.

[0304] In some embodiments, referring to Figure 4a-4d each energy storage unit includes a battery subunit, and each energy storage unit is configured to provide the second direct current based on the electrical energy of the battery subunit.

[0305] For example, referring to Figure 4a the energy storage unit A1 includes the battery subunit BAT1, and the energy storage unit A n-1 includes the battery subunit BAT n-1 , the energy storage unit A n includes the battery subunit BAT n . Each energy storage unit provides the second direct current based on the electrical energy of the battery subunit, and the plurality of energy storage units provide the first direct current to the charging module 120 through series and / or parallel connection.

[0306] In some embodiments, referring to Figure 4b at least part of the one or more energy storage units further includes a first power conversion subunit, the first power conversion subunit is connected to the corresponding battery subunit and the first positive power supply end and the first negative power supply end of the energy storage unit, and is configured to convert the electrical energy of the battery subunit into the second direct current; wherein, in the case that the energy storage unit does not include the first power conversion subunit, the battery subunit is directly connected to the first positive power supply end and the first negative power supply end of the corresponding energy storage unit to provide the second direct current.

[0307] Specifically, when the energy storage unit is one, the energy storage unit further includes the first power conversion subunit to convert the electrical energy of the battery subunit into the second direct current.

[0308] When the energy storage unit is a plurality, a first power conversion subunit can be provided in each of the plurality of energy storage units, or a first power conversion subunit can be provided in part of the plurality of energy storage units. For example, in Figure 4bIn the embodiment, the energy storage unit A1 includes a battery subunit BAT1 and a first power conversion subunit B1. The first power conversion subunit B1 is connected to the first positive power supply terminal and the first negative power supply terminal of the battery subunit BAT1 and the energy storage unit A1 respectively. The first power conversion subunit B1 converts the electric energy of the battery subunit BAT1 into a second direct current. n-1 Including battery subunit BAT n-1 and the first power conversion subunit B n-1 , the first power conversion sub-unit Bn-1 is respectively connected to the battery sub-unit BAT n-1 and energy storage unit A n-1 The first positive power supply terminal and the first negative power supply terminal are connected to each other through the first power conversion subunit B n-1 The battery subunit BAT n-1 The electrical energy is converted into the second direct current; the energy storage unit A n Including battery subunit BAT n , battery subunit BAT n Directly with energy storage unit A n The first positive power supply terminal and the first negative power supply terminal are connected to provide a second direct current.

[0309] In some embodiments, when the battery subunit is discharging, the maximum output power of the first power conversion subunit is greater than or equal to 350 kilowatts, and / or the rated output power is greater than or equal to 310 kilowatts. When the battery subunit is charging, the ratio of the maximum output power of the input module 130 to the maximum output power of the first power conversion subunit is no greater than 1:4, and / or the ratio of the rated output power of the input module 130 to the rated output power of the first power conversion subunit is no greater than 1:4.

[0310] In the above embodiment, some or all of the multiple energy storage units can be provided with a first power conversion sub-unit, and the electric energy of the battery sub-unit is converted by the first power conversion sub-unit to provide a second direct current. This can improve the flexibility of charging. At the same time, by partially setting up the first power conversion sub-unit, the cost can be reduced while meeting the charging needs. Moreover, this method can realize the access with and without the first power conversion sub-unit, and has high applicability.

[0311] In some embodiments, reference Figure 4cAt least some of the one or more energy storage units further include a first switch subunit, which is respectively connected to the first positive power supply terminal and the first negative power supply terminal of the corresponding battery subunit and the energy storage unit, and is configured to connect the corresponding battery subunit to the first positive power supply terminal and the first negative power supply terminal of the energy storage unit when it is turned on to provide a second direct current; wherein, when the energy storage unit does not include the first switch subunit, the battery subunit is directly connected to the first positive power supply terminal and the first negative power supply terminal of the corresponding energy storage unit to provide the second direct current.

[0312] Specifically, when there is only one energy storage unit, the energy storage unit also includes a first switch subunit. When the first switch subunit is turned on, the battery subunit is connected to the first positive power supply terminal and the first negative power supply terminal of the energy storage unit to provide a second direct current; in abnormal circumstances, such as abnormalities in the battery subunit or the charging module 120, the first switch subunit is disconnected to reduce the further occurrence of abnormal accidents; when the battery subunit does not need to work, such as when the energy storage unit does not need to work based on power requirements, the first switch subunit is disconnected to stop the battery subunit from providing the second direct current.

[0313] When there are multiple energy storage units, a first switch sub-unit may be provided in each of the multiple energy storage units, or a first switch sub-unit may be provided in some of the multiple energy storage units. Figure 4c In the embodiment, the energy storage unit A1 includes a battery subunit BAT1 and a first switch subunit C1. The first switch subunit C1 is connected to the first positive power supply terminal and the first negative power supply terminal of the battery subunit BAT1 and the energy storage unit A1, respectively. The first switch subunit C1 controls the on-off of the battery subunit BAT1 and the first positive power supply terminal and the first negative power supply terminal of the energy storage unit A1 to selectively provide a second direct current. n-1 Including battery subunit BAT n-1 and the first switch subunit C n-1 , the first switch subunit C n-1 Respectively with the battery subunit BAT n-1 and energy storage unit A n-1 The first positive power supply terminal and the first negative power supply terminal are connected to each other through the first switch subunit C n-1 Control battery subunit BAT n-1 With energy storage unit A n-1 The first positive power supply terminal and the first negative power supply terminal are turned on and off to selectively provide a second direct current; the energy storage unit A n Including battery subunit BAT n , battery subunit BAT n Directly with energy storage unit A nThe first positive power terminal and the first negative power terminal of the first energy storage unit are connected to the first positive power terminal and the first negative power terminal of the battery subunit, so as to provide the second direct current.

[0314] In the above embodiments, part or all of the plurality of energy storage units can be provided with the first switch subunit, and the battery subunit is selectively controlled to provide the second direct current through the first switch subunit, so as to improve the flexibility of charging and protection in abnormal conditions.

[0315] In some embodiments, referring to Figure 4d , at least part of the one or more energy storage units further comprises a first power conversion subunit and a first switch subunit, the first power conversion subunit and the first switch subunit are connected in series between the corresponding battery subunit and the first positive power terminal and the first negative power terminal of the energy storage unit, and the first power conversion subunit is configured to convert the electrical energy of the battery subunit into the second direct current when the corresponding first switch subunit is turned on; wherein, in the case that the energy storage unit does not comprise the first power conversion subunit and the first switch subunit, the battery subunit is directly connected to the first positive power terminal and the first negative power terminal of the corresponding energy storage unit to provide the second direct current.

[0316] Specifically, when the energy storage unit is one, the energy storage unit further comprises a first power conversion subunit and a first switch subunit, and the first power conversion subunit converts the electrical energy of the battery subunit into the second direct current when the first switch subunit is turned on; in abnormal conditions, such as abnormality of the battery subunit or the charging module 120, the first switch subunit is turned off, and the first power conversion subunit stops working to reduce further occurrence of abnormal accidents; when the battery subunit does not need to work, such as when the energy storage unit does not need to work based on power demand, the first switch subunit is turned off, and the first power conversion subunit stops working to make the battery subunit stop providing the second direct current.

[0317] When the energy storage unit is a plurality, a first switch subunit and a first power conversion subunit can be provided in each of the plurality of energy storage units, or a first switch subunit and a first power conversion subunit can be provided in part of the plurality of energy storage units. For example, Figure 4d , the energy storage unit A1 comprises a battery subunit BAT1, a first switch subunit C1 and a first power conversion subunit B1, the first switch subunit C1 and the first power conversion subunit B1 are connected in series between the battery subunit BAT1 and the first positive power terminal and the first negative power terminal of the energy storage unit A1, and the first power conversion subunit B1 converts the electrical energy of the battery subunit BAT1 into the second direct current when the first switch subunit C1 is turned on;...; the energy storage unit A n-1 comprises a battery subunit BAT n-1 , a first switch subunit C n-1 and a first power conversion subunit Bn-1 , the first switch subunit C n-1 and the first power conversion subunit B n-1 is connected in series with the battery subunit BAT n-1 and the energy storage unit A n-1 between the first positive power supply end and the first negative power supply end of the energy storage unit A n-1 , in the case of being turned on, the first power conversion subunit B n-1 converts the electric energy of the battery subunit BAT n-1 into the second direct current; the energy storage unit A n includes the battery subunit BAT n , the battery subunit BAT n is directly connected with the first positive power supply end and the first negative power supply end of the energy storage unit A n to provide the second direct current.

[0318] It should be noted that in some embodiments, a part of the energy storage unit can also include the first switch subunit, and the other part includes the first power conversion subunit, which is not limited here.

[0319] In the above embodiments, part or all of the plurality of energy storage units can be provided with the first switch subunit and the first power conversion subunit, so as to improve the flexibility of charging and the protection ability in abnormal conditions.

[0320] In some embodiments, the first power conversion subunit is a bidirectional DCDC subunit, and charging and discharging of the battery subunit are realized through the bidirectional DCDC subunit. The bidirectional DCDC subunit includes but is not limited to a BUCK-BOOST circuit and the like, which is not limited here.

[0321] In some embodiments, referring to Figure 5a , the input module 130 includes an input interface (X, Y), which is connected with the second positive power supply end and the second negative power supply end of the energy storage module 110, and is configured to provide charging energy for each energy storage unit based on the third direct current provided by the first external power supply 210.

[0322] Specifically, the first external power supply 210 is used to generate the third direct current, and transmit it to the energy storage module 110 through the input interface to charge each energy storage unit in the energy storage module 110. For example, the first external power supply 210 can include a first transformer and a first AC / DC conversion module. The primary winding of the first transformer is connected with the AC power grid to convert the second alternating current provided by the AC power grid into the first alternating current. The first AC / DC conversion module is connected with the secondary winding of the first transformer and the input interface respectively to convert the first alternating current into the third direct current and transmit it to the energy storage module 110 through the input interface.

[0323] The first AC-DC conversion module can be a unidirectional ACDC subunit or a bidirectional ACDC subunit. When the first AC-DC conversion module is a bidirectional ACDC subunit, not only charging of the energy storage module 110 can be implemented, but also electric energy of the energy storage module 110 can be fed to the AC power grid. The specific circuit structure of the unidirectional ACDC subunit or the bidirectional ACDC subunit is not limited here.

[0324] It should be noted that in this example, the maximum output power and the rated output power of the input module 130 are also the maximum output power and the rated output power of the first external power supply 210.

[0325] In the above embodiment, when the external power supply provides direct current, the battery subunit can be charged through the input interface.

[0326] In some embodiments, referring to Figure 5b The input module 130 includes a second power conversion subunit 131 connected to the second positive power supply end and the second negative power supply end of the energy storage module 110 and configured to provide charging energy for each energy storage unit based on the first AC power provided by the second external power supply 220.

[0327] Specifically, the second external power supply 220 is configured to generate the first AC power and provide the first AC power to the second power conversion subunit 131 in the input module 130, so as to charge each battery subunit in the energy storage module 110 through the second power conversion subunit 131. For example, the second external power supply 220 can include a first transformer, a primary winding of the first transformer being connected to the AC power grid, and the second power conversion subunit 131 being connected to a secondary winding of the first transformer and the energy storage module 110, respectively. The first transformer converts the second AC power provided by the AC power grid into the first AC power and provides the first AC power to the second power conversion subunit 131, and the second power conversion subunit 131 converts the first AC power into the third DC power to charge the energy storage module 110.

[0328] The second power conversion subunit 131 can be a unidirectional ACDC subunit or a bidirectional ACDC subunit. When the second power conversion subunit 131 is a bidirectional ACDC subunit, not only charging of the energy storage module 110 can be implemented, but also electric energy of the energy storage module 110 can be fed to the AC power grid. The specific circuit structure of the unidirectional ACDC subunit or the bidirectional ACDC subunit is not limited here.

[0329] It should be noted that in this example, the maximum output power and the rated output power of the input module 130 are also the maximum output power and the rated output power of the second power conversion subunit 131.

[0330] In the above embodiments, when the external power supply provides alternating current, the battery subunit can be charged by the second power conversion subunit.

[0331] In some embodiments, referring to Figure 6a , 6b , 9a, 9b, 11a, 11b, and Figure 14- Figure 22 , the charging module 120 includes a charging module conversion unit and at least one charging gun 122, and the charging gun 122 is connected to the energy storage module 110 through the charging module conversion unit.

[0332] The number of charging guns 122 can be one, two, or more. For example, the number of charging guns 122 is two, and the maximum charging output power or rated output power of each charging gun 122 can be 500kW, which can simultaneously charge the same electric device, which can be an electric vehicle, and each charging gun 122 can also individually charge different electric devices.

[0333] When the number of charging guns 122 is multiple, multiple charging guns 122 can be connected to the energy storage module 110 through the same charging module conversion unit, and each charging gun 122 can also be individually connected to the energy storage module 110 through a charging module conversion unit. The charging module conversion unit can be a DCDC conversion unit, which can be a unipolar one-way DCDC conversion unit or a unipolar bidirectional DCDC conversion unit, or a bipolar one-way DCDC conversion unit or a bipolar bidirectional DCDC conversion unit.

[0334] The charging module conversion unit can flexibly adjust the voltage, current, and other parameters according to the direct current output by the energy storage module 110 and the requirements of the charging gun 122 connected device (such as an electric vehicle), to achieve efficient charging output. The configuration of at least one charging gun 122 allows the charging device 100 to simultaneously charge one or more electric devices. In a public charging area, such as a parking lot, a charging station, etc., multiple users can simultaneously use different charging guns 122 to charge their electric vehicles, improving the use efficiency and service capacity of the charging device 100, meeting the use requirements in large-scale charging demand scenarios, effectively alleviating the charging queuing and waiting problem, and improving the user experience.

[0335] In some embodiments, referring to Figure 6aThe charging module 120 includes a third power conversion subunit 121 and a charging gun 122. The positive input end and the negative input end of the third power conversion subunit 121 are connected to the second positive power supply end and the second negative power supply end of the energy storage module 110, respectively. The positive output end and the negative output end of the third power conversion subunit 121 are connected to the positive input end and the negative input end of the charging gun 122, respectively. The third power conversion subunit 121 is configured to convert the first direct current into a fourth direct current for charging output through the charging gun 122.

[0336] Specifically, when charging the device to be charged, the one or more energy storage units provide the second direct current, so that the energy storage module 110 provides the first direct current, which is converted into the fourth direct current by the third power conversion subunit 121 and provided to the charging gun 122, and then provided to the device to be charged by the charging gun 122, so as to charge the device to be charged.

[0337] In this example, the third power conversion subunit 121 has bipolarity, i.e., has a positive input end and a negative input end. At this time, the positive input end and the negative input end of the third power conversion subunit 121 are directly connected to the second positive power supply end and the second negative power supply end of the energy storage module 110, respectively. The positive output end and the negative output end of the third power conversion subunit 121 are directly connected to the positive input end and the negative input end of the charging gun 122, respectively. The negative input end of the charging gun 122 and the second negative power supply end of the energy storage module 110 are not shared. In this way, it is suitable for the application scenario in which the third power conversion subunit 121 has bipolarity.

[0338] The third power conversion subunit 121 can be a bipolar unidirectional DCDC subunit or a bipolar bidirectional DCDC subunit. When the third power conversion subunit 121 is a bipolar bidirectional DCDC subunit, not only can the device to be charged be charged, but also the electrical energy of the device to be charged can be fed to the energy storage module 110, and can also be fed to the AC power grid in the foregoing example through the input module 130, so as to ultimately realize the free conversion of electrical energy among the grid, the charging, and the storage.

[0339] In some embodiments, referring to Figure 6b The charging module 120 includes a fourth power conversion subunit 123 and the charging gun 122. The positive input end of the fourth power conversion subunit 123 is connected to the second positive power supply end of the energy storage module 110. The positive output end of the fourth power conversion subunit 123 is connected to the positive input end of the charging gun 122. The negative input end of the charging gun 122 is connected to the second negative power supply end of the energy storage module 110. The fourth power conversion subunit 123 is configured to convert the first direct current into a fourth direct current for charging output through the charging gun 122.

[0340] Specifically, when charging the device to be charged, one or more energy storage units provide the second direct current, so that the energy storage module 110 provides the first direct current, and the first direct current is converted into the fourth direct current by the fourth power conversion sub-unit 123 and provided to the charging gun 122, which is provided by the charging gun 122 to the device to be charged to charge the device to be charged.

[0341] In this example, the fourth power conversion subunit 123 is unipolar, that is, it has only a positive input terminal. In this case, the positive input terminal of the fourth power conversion subunit 123 is directly connected to the second positive power supply terminal of the energy storage module 110, the positive output terminal of the fourth power conversion subunit 123 is directly connected to the positive input terminal of the charging gun 122, and the negative input terminal of the charging gun 122 is directly connected to the second negative power supply terminal of the energy storage module 110. That is, the negative input terminal of the charging gun 122 and the second negative power supply terminal of the energy storage module 110 are shared. This is suitable for application scenarios where the fourth power conversion subunit 123 has a unipolarity and is low-cost.

[0342] The fourth power conversion subunit 123 can be a unipolar unidirectional DCDC subunit or a unipolar bidirectional DCDC subunit. When the fourth power conversion subunit 123 is a unipolar bidirectional DCDC subunit, it can not only charge the device to be charged, but also feed the power of the device to be charged to the energy storage module 110, and can also feed the power to the AC power grid of the aforementioned example through the input module 130, ultimately realizing the free conversion of electric energy between the grid, charging, and storage.

[0343] In the above embodiment, by sharing or not sharing the negative input terminal of the charging gun, it can be applied to different power supply scenarios, thereby increasing the range of choices when selecting the circuit structure.

[0344] In some embodiments, reference Figure 7 The energy storage module 110 further includes a selection unit 111, which is connected to one or more energy storage units and is configured to select at least one energy storage unit from the one or more energy storage units and connect it to the second positive power supply terminal and the second negative power supply terminal of the energy storage module 110 to provide a first direct current.

[0345] Specifically, when charging, the selection unit 111 can select an energy storage unit A1 to be connected to the second positive power supply terminal and the second negative power supply terminal of the energy storage module 110 to provide the first direct current; or select all energy storage units A1, ..., energy storage units A n-1 and energy storage unit A n The first DC power supply is connected to the second positive power supply terminal and the second negative power supply terminal of the energy storage module 110 to provide a first DC power. Then, the charging module 120 performs charging output based on the first DC power.

[0346] In the above embodiment, the energy storage unit is selectively controlled by the selection unit to output, so that the flexibility of charging can be improved, and different charging requirements can be met.

[0347] In some embodiments, referring to Figure 8 , the second positive power supply end and the second negative power supply end of the energy storage module 110 each include one, the selection unit 111 includes a plurality of second switch sub-units, each of which is connected with one energy storage unit, each second switch sub-unit is connected in series between the first positive power supply end of the corresponding energy storage unit and the second positive power supply end of the energy storage module 110, and the first negative power supply end of one or more energy storage units is respectively connected with the second negative power supply end of the energy storage module 110. The second switch sub-unit is configured to connect the first positive power supply end of the corresponding energy storage unit with the second positive power supply end of the energy storage module 110 in the on state.

[0348] Specifically, the selection unit 111 includes a second switch sub-unit K1,..., a second switch sub-unit Kn-1, and a second switch sub-unit Kn, wherein the second switch sub-unit K1 is connected in series between the first positive power supply end of the energy storage unit A1 and the second positive power supply end of the energy storage module 110,..., the second switch sub-unit Kn-1 is connected in series between the first positive power supply end of the energy storage unit A n-1 and the second positive power supply end of the energy storage module 110, and the second switch sub-unit Kn is connected in series between the first positive power supply end of the energy storage unit A n and the second positive power supply end of the energy storage module 110. By controlling the on-off of the second switch sub-unit, the corresponding energy storage unit is selected to provide the second direct current, so that the energy storage module 110 provides the first direct current, and at this time the charging module 120 converts the first direct current into the fourth direct current to charge the device to be charged.

[0349] In the above embodiment, by providing one second positive power supply end and selectively controlling the energy storage unit to provide the second direct current by the selection unit, the flexibility of charging can be improved, and the charging requirement can be met.

[0350] In some embodiments, referring to Figure 9a , the charging module 120 includes a fifth power conversion sub-unit 124 and a charging gun 122, the positive input end and the negative input end of the fifth power conversion sub-unit 124 are connected with the second positive power supply end and the second negative power supply end of the energy storage module 110, respectively, the positive output end and the negative output end of the fifth power conversion sub-unit 124 are connected with the positive input end and the negative input end of the charging gun 122, respectively, and the fifth power conversion sub-unit 124 is configured to convert the first direct current into the fourth direct current for charging output through the charging gun 122.

[0351] It should be noted that, for the connection relationship of the fifth power conversion subunit 124 with the charging gun 122 and the energy storage module 110 and the structure of the fifth power conversion subunit 124, please refer to the foregoing description of the third power conversion subunit 121, and details are not repeated here.

[0352] In some embodiments, referring to Figure 9b , the charging module 120 includes the sixth power conversion subunit 125 and the charging gun 122, the positive input end of the sixth power conversion subunit 125 is connected with the second positive power supply end of the energy storage module 110, the positive output end of the sixth power conversion subunit 125 is connected with the positive input end of the charging gun 122, the negative input end of the charging gun 122 is connected with the second negative power supply end of the energy storage module 110, and the sixth power conversion subunit 125 is configured to convert the first direct current into the fourth direct current for charging output through the charging gun 122.

[0353] It should be noted that, for the connection relationship of the sixth power conversion subunit 125 with the charging gun 122 and the energy storage module 110 and the structure of the sixth power conversion subunit 125, please refer to the foregoing description of the fourth power conversion subunit 123, and details are not repeated here.

[0354] In some embodiments, referring to Figure 10 , the second positive power supply end of the energy storage module 110 includes multiple, the second negative power supply end of the energy storage module 110 includes one, and the selection unit 111 includes multiple second switch subunits, each of which is connected with one energy storage unit and one second positive power supply end, each second switch subunit is connected in series between the first positive power supply end of the corresponding energy storage unit and the corresponding second positive power supply end, and the first negative power supply end of one or more energy storage units is respectively connected with the second negative power supply end of the energy storage module 110, and the second switch subunit is configured to connect the first positive power supply end of the corresponding energy storage unit with the corresponding second positive power supply end in the case of conduction.

[0355] Specifically, the selection unit 111 includes the second switch subunit K1,..., the second switch subunit Kn-1, and the second switch subunit Kn, wherein the second switch subunit K1 is connected in series between the first positive power supply end of the energy storage unit A1 and one second positive power supply end of the energy storage module 110,..., the second switch subunit Kn-1 is connected in series between the first positive power supply end of the energy storage unit A n-1 , and the second switch subunit Kn is connected in series between the first positive power supply end of the energy storage unit A nThe first positive power supply terminal of the energy storage module 110 is connected to the second positive power supply terminal of the energy storage module 110. By controlling the on / off of the second switch sub-unit, the corresponding energy storage unit is selected to provide the second DC power, thereby causing the energy storage module 110 to provide the first DC power. At this time, the charging module 120 converts the first DC power into a fourth DC power to charge the device to be charged. It should be noted that the first DC power here includes multiple second DC power sources, and the charging module 120 can selectively convert one or more second DC power sources into the fourth DC power source.

[0356] In the above embodiment, by providing a plurality of second positive power supply terminals and selectively controlling the energy storage unit to provide the second direct current through the selection unit, the flexibility of charging can be improved to meet the charging demand.

[0357] In some embodiments, reference Figure 11a The charging module 120 includes multiple seventh power conversion sub-units and a charging gun 122. The positive input terminal and the negative input terminal of each seventh power conversion sub-unit are correspondingly connected to a second positive power supply terminal and a second negative power supply terminal, and the positive output terminal and the negative output terminal of each seventh power conversion sub-unit are correspondingly connected to the positive input terminal and the negative input terminal of the charging gun. The multiple seventh power conversion sub-units are configured to convert the first direct current into a fourth direct current for charging output through the charging gun.

[0358] Specifically, the plurality of seventh power conversion sub-units are respectively a seventh power conversion sub-unit D1, ..., a seventh power conversion sub-unit D n-1 and the seventh power conversion subunit D n , wherein the positive input terminal of the seventh power conversion subunit D1 is connected to a second positive power supply terminal, ..., the seventh power conversion subunit D n-1 The positive input terminal of the seventh power conversion sub-unit D is connected to another second positive power supply terminal. n The positive input terminal of the seventh power conversion sub-unit D1 is connected to another second positive power supply terminal, and the seventh power conversion sub-unit D1, ..., the seventh power conversion sub-unit D n-1 and the seventh power conversion subunit D n The negative input terminals of the seventh power conversion subunits D1, ..., the seventh power conversion subunits D n-1 and the seventh power conversion subunit D n The positive output terminal and the negative output terminal of the charging gun 122 are respectively connected to the positive input terminal and the negative input terminal of the charging gun 122.

[0359] In this example, each seventh power conversion sub-unit may convert the second direct current of the corresponding energy storage unit into the fifth direct current, and finally the plurality of seventh power conversion sub-units output the fourth direct current.

[0360] The seventh power conversion subunit can be a bipolar unidirectional DCDC subunit or a bipolar bidirectional DCDC subunit. When the seventh power conversion subunit is a bipolar bidirectional DCDC subunit, it can not only charge the device to be charged, but also feed the power of the device to be charged to the energy storage module 110, and can also feed the power to the AC power grid of the aforementioned example through the input module 130, ultimately realizing the free conversion of electric energy between the grid, charging, and storage.

[0361] In some embodiments, reference Figure 11b The charging module 120 includes multiple eighth power conversion subunits and a charging gun 122. The positive input terminal of each eighth power conversion subunit is connected to a second positive power supply terminal, the positive output terminal of each eighth power conversion subunit is connected to the positive input terminal of the charging gun 122, and the negative input terminal of the charging gun 122 is connected to the second negative power supply terminal of the energy storage module 110. The multiple eighth power conversion subunits are configured to convert the first direct current into a fourth direct current for charging output through the charging gun 122.

[0362] Specifically, the plurality of eighth power conversion sub-units are respectively an eighth power conversion sub-unit E1, ..., an eighth power conversion sub-unit E2, ..., an eighth power conversion sub-unit E3, ..., an eighth power conversion sub-unit E4, ..., an eighth power conversion sub-unit E5, ..., an eighth power conversion sub-unit E6, ..., an eighth power conversion sub-unit E7, ..., an eighth power conversion sub-unit E8, ..., an eighth power conversion sub-unit E9, ..., an eighth power conversion sub n-1 and the eighth power conversion subunit E n , wherein the positive input terminal of the eighth power conversion sub-unit E1 is connected to a second positive power supply terminal, ..., the eighth power conversion sub-unit E n-1 The positive input terminal of the eighth power conversion sub-unit E is connected to another second positive power supply terminal. n The positive input terminal of the eighth power conversion sub-unit E1 is connected to another second positive power supply terminal, and the eighth power conversion sub-unit E1, ..., the eighth power conversion sub-unit E n-1 and the eighth power conversion subunit E n The positive output terminals of the charging gun 122 are connected to the positive input terminal of the charging gun 122 , and the negative input terminal of the charging gun 122 is connected to the second negative power supply terminal of the energy storage module 110 .

[0363] In this example, each eighth power conversion sub-unit may convert the second direct current of the corresponding energy storage unit into the fifth direct current, and finally the plurality of eighth power conversion sub-units output the fourth direct current.

[0364] The eighth power conversion subunit can be a unipolar unidirectional DCDC subunit or a unipolar bidirectional DCDC subunit. When the eighth power conversion subunit is a unipolar bidirectional DCDC subunit, it can not only charge the device to be charged, but also feed the electric energy of the device to be charged to the energy storage module 110, and can also feed the electric energy to the AC power grid of the aforementioned example through the input module 130, ultimately realizing the free conversion of electric energy between the grid, charging, and storage.

[0365] In the above embodiment, by sharing or not sharing the negative input terminal of the charging gun, it can be applied to different power supply scenarios, thereby increasing the range of choices when selecting the circuit structure.

[0366] In some embodiments, reference Figure 12a The input module 130 includes a ninth power conversion subunit 132 , which is connected to one or more energy storage units and is configured to provide charging energy to each energy storage unit based on the first alternating current provided by the second external power source 220 .

[0367] Specifically, the second external power source 220 is used to generate a first alternating current (AC) and provide it to the ninth power conversion subunit 132 in the input module 130. The ninth power conversion subunit 132 is used to charge the battery subunits in the energy storage module 110. Exemplarily, the second external power source 220 may include a second transformer, wherein the primary winding of the second transformer is connected to the AC grid, and the secondary winding of the second transformer is connected to the ninth power conversion subunit 132. The second transformer converts the second AC power provided by the AC grid into a first AC power, which is provided to the ninth power conversion subunit 132. The ninth power conversion subunit 132 converts the first AC power into a third DC power to charge the energy storage module 110.

[0368] Exemplarily, the second external power source 220 is a three-phase AC power source, and the ninth power conversion subunit 132 is a unidirectional three-phase ACDC subunit or a bidirectional three-phase ACDC subunit. In this case, each phase of the three-phase ACDC subunit is connected to an energy storage unit to charge the corresponding energy storage unit. When the ninth power conversion subunit 132 is a bidirectional three-phase ACDC subunit, not only can the energy storage module 110 be charged, but the electric energy of the energy storage module 110 can also be fed to the AC power grid. In this way, in the three-phase AC power, a single phase is implemented by an energy storage unit, and the three energy storage units can realize the function of three-phase AC power, for example, three-phase industrial frequency AC power with a phase difference of 120°. The specific circuit structure of the unidirectional three-phase ACDC subunit or the bidirectional three-phase ACDC subunit is not limited here.

[0369] It should be noted that, in this example, the maximum output power and the rated output power of the input module 130 are also the maximum output power and the rated output power of the ninth power conversion sub-unit 132 .

[0370] In the above embodiment, when the external power source provides alternating current, the battery subunit can be charged through the ninth power conversion subunit.

[0371] In some embodiments, reference Figure 12bThe input module 130 includes a plurality of tenth power conversion sub-units, each of which is connected with one energy storage unit, and the plurality of tenth power conversion sub-units are configured to provide charging energy for each energy storage unit based on the first alternating current provided by the second external power supply 220.

[0372] Specifically, the plurality of tenth power conversion sub-units are respectively a tenth power conversion sub-unit F1, a tenth power conversion sub-unit F2, a tenth power conversion sub-unit F3, a tenth power conversion sub-unit F4, a tenth power conversion sub-unit F5, a tenth power conversion sub-unit F6, a tenth power conversion sub-unit F7, a tenth power conversion sub-unit F8, a tenth power conversion sub-unit F9, and a tenth power conversion sub-unit F10. n-1 The tenth power conversion sub-unit F1 is connected with the second external power supply 220 and the energy storage unit A1, respectively. n The tenth power conversion sub-unit F2 is connected with the second external power supply 220 and the energy storage unit A2, respectively. n-1 The tenth power conversion sub-unit F3 is connected with the second external power supply 220 and the energy storage unit A3, respectively. n-1 The tenth power conversion sub-unit F4 is connected with the second external power supply 220 and the energy storage unit A4, respectively. n The tenth power conversion sub-unit F5 is connected with the second external power supply 220 and the energy storage unit A5, respectively. n The tenth power conversion sub-unit F6 is connected with the second external power supply 220 and the energy storage unit A6, respectively. Each tenth power conversion sub-unit can charge the corresponding energy storage unit based on the first alternating current provided by the second external power supply 220.

[0373] For example, the second external power supply 220 is a three-phase alternating current power supply, and the tenth power conversion sub-units include three, each of which is a unidirectional single-phase ACDC sub-unit or a bidirectional single-phase ACDC sub-unit, at this time, each tenth power conversion sub-unit is connected to one phase of the three-phase alternating current power supply to charge the corresponding energy storage unit. When the tenth power conversion sub-unit is a bidirectional single-phase ACDC sub-unit, not only can the charging of the energy storage module 110 be realized, but also the electrical energy of the energy storage module 110 can be fed to the alternating current grid, and when feeding, the three bidirectional single-phase ACDC sub-units cooperate with each other to form a three-phase alternating current fed to a three-phase alternating current grid, so that in the three-phase alternating current, the single-phase is realized by the energy storage unit, and the three energy storage units can realize the function of the three-phase alternating current. The specific circuit structure of the unidirectional single-phase ACDC sub-unit or the bidirectional single-phase ACDC sub-unit is not limited here.

[0374] It should be noted that in this example, the maximum output power and the rated output power of the input module 130 are the sum of the maximum output power and the rated output power of the plurality of tenth power conversion sub-units.

[0375] In the above embodiment, in the case of an alternating current provided by an external power supply, the battery sub-units can be charged by the plurality of tenth power conversion sub-units.

[0376] In some embodiments, with reference to Figure 13The charging device 100 further comprises a wireless communication module 140, at least part of the energy storage module 110, the input module 130 and the charging module 120 are connected to the wireless communication module 140, so as to interact with external devices through the wireless communication module 140.

[0377] It should be noted that in the above embodiments, various charging device architectures are provided, for example, multiple energy storage units can be connected in series, in parallel or in series-parallel; part or all of the multiple energy storage units can be provided with the first power conversion subunit, the first switch subunit or the first power conversion subunit and the first switch subunit; the charging module can adopt a unipolar power conversion subunit or a bipolar power conversion subunit, and the negative input end of the corresponding charging pile can be shared or not shared; a single phase of three-phase alternating current is realized by an energy storage unit, and three energy storage units can realize the function of three-phase alternating current; the input module can be an alternating current input or a direct current input; and the like.

[0378] In order for those skilled in the art to more clearly understand the present application, specific examples will be described below, but this should not be considered as a limitation of the present application.

[0379] Example one, with reference to Figure 14 The energy storage module 110 comprises multiple energy storage units, each energy storage unit comprising a battery subunit and a first power conversion subunit, the first power conversion subunit being a bidirectional DCDC subunit, the multiple energy storage units being connected in series between the second positive power supply end and the second negative power supply end of the energy storage module 110, and the second positive power supply end and the second negative power supply end of the energy storage module 110 being connected to the DC bus, i.e. the multiple energy storage units are connected in series on the DC bus. The charging module 120 comprises a third power conversion subunit 121 and a charging gun 122, the third power conversion subunit 121 having a high-voltage positive input end and a high-voltage negative input end, and a high-voltage positive output end and a high-voltage negative output end, the third power conversion subunit 121 being a bipolar bidirectional DCDC subunit. The input module 130 comprises a second power conversion subunit 131, which is a bidirectional ACDC subunit. The second external power supply 220 comprises a first transformer connected to an alternating current grid.

[0380] When charging the energy storage module 110, the first transformer converts the second alternating current provided by the alternating current grid into the first alternating current, which is converted into direct current by the bidirectional ACDC subunit and then charges each battery subunit in the energy storage module 110 through the DC bus.

[0381] When charging the device to be charged, the energy storage unit provides second direct current based on the electric energy of the battery subunit, the energy storage module 110 obtains first direct current based on the second direct current, the first direct current is converted into fourth direct current through the high-power bipolar bidirectional DCDC subunit, and the fourth direct current charges the device to be charged through the charging gun 122, so as to realize high-power charging and fast charging / super charging of the device to be charged.

[0382] It can be understood that under the action of the bidirectional ACDC subunit and the bipolar bidirectional DCDC subunit, the electric energy of the device to be charged can also be fed to the energy storage module 110 or the alternating current power grid, so as to realize free switching of electric energy among the device to be charged, the energy storage module 110 and the alternating current power grid.

[0383] Example two, referring to Figure 15 , the difference between this example and the example shown in Figure 14 is that the fourth power conversion subunit 123 only has a high-voltage positive input end and a high-voltage positive output end, the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, that is, the negative poles of the charging gun 122 and the energy storage module 110 are shared, and the fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. For the same content, to avoid redundancy, this will not be repeated here.

[0384] Example three, referring to Figure 16 , the difference between this example and the example shown in Figure 14 is that a plurality of energy storage units are connected in parallel between the second positive power supply end and the second negative power supply end of the energy storage module 110, that is, the plurality of energy storage units are connected in parallel to the direct current bus.

[0385] Example four, referring to Figure 17 , the difference between this example and the example shown in Figure 16 is that the fourth power conversion subunit 123 only has a high-voltage positive input end and a high-voltage positive output end, the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, that is, the negative poles of the charging gun 122 and the energy storage module 110 are shared, and the fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit.

[0386] Example five, referring to Figure 18 , the difference between this example and the example shown in Figure 14 is that part of the plurality of energy storage units includes a battery subunit, and the other part of the plurality of energy storage units includes a battery subunit and a first power conversion subunit, for example, the energy storage unit A1 includes a battery subunit, and the energy storage unit A n includes a battery subunit and a bidirectional DCDC subunit A n .

[0387] Example six, referring toFigure 19 The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. Figure 18 The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit.

[0388] The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. Figure 20 The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. Figure 16 The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit. The example shown in FIG. 8 is different from the example shown in FIG. 7 in that the fourth power conversion subunit 123 has only a high-voltage positive input end and a high-voltage positive output end, and the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, i.e., the negative poles of the charging gun 122 and the energy storage module 110 are shared. The fourth power conversion subunit 123 can be a unipolar bidirectional DCDC subunit.

[0389] In the above examples one to seven, the energy storage module 110 and the charging module 120 are connected to the DC bus, i.e., the charging device 100 adopts the DC bus design. When the energy storage module 110 and the charging module 120 are both provided as multiple, multiple charging devices 100 share the DC bus. When the charging device 100 adopts the DC bus design, in the case where the maximum charging output power of the charging device 100 is greater than or equal to 350 kW, the maximum output power of the battery subunit is greater than or equal to 350 kW, the rated power of the battery subunit is greater than or equal to 350 kW, the rated energy of the battery subunit is greater than or equal to 58 kW, the maximum discharge rate of the battery subunit is greater than or equal to 4C, the maximum output power of the first power conversion subunit is greater than or equal to 350 kW, and the rated power of the first power conversion subunit is greater than or equal to 310 kW, the maximum output power of the input module 130 is less than or equal to 150 kW, and the ratio of the maximum output power of the input module 130 to the maximum output power of the first power conversion subunit is not greater than 1:4.

[0390] Example eight, referring to FIG. 8, the energy storage module 110 includes three energy storage units A1, A2 and A3 and a selection unit 111, each energy storage unit includes a battery subunit, and the selection unit 111 includes three second switch subunits K1, K2 and K3. The charging module 120 includes a fifth power conversion subunit 124 and a charging gun 122, the fifth power conversion subunit 124 has a high-voltage positive input end and a high-voltage negative input end, and a high-voltage positive output end and a high-voltage negative output end, and the fifth power conversion subunit 124 can be a bipolar bidirectional DCDC subunit. The input module 130 includes three tenth power conversion subunits, which can be bidirectional single-phase ACDC subunits. The second external power supply 220 includes a second transformer connected to an alternating current power grid. Figure 21

[0391] When charging the energy storage module 110, the second transformer converts the second alternating current provided by the alternating current grid into the first alternating current, which is converted into direct current by the bidirectional single-phase AC-DC subunit, and then charges the corresponding battery subunit. Among them, each bidirectional single-phase AC-DC subunit is connected to one phase of the alternating current bus, for example, the first bidirectional single-phase AC-DC subunit is connected to phase A, the second bidirectional single-phase AC-DC subunit is connected to phase B, and the third bidirectional single-phase AC-DC subunit is connected to phase C. It should be noted that under the action of the bidirectional single-phase AC-DC subunit, when the electrical energy in the energy storage module 110 is fed to the alternating current grid, the three bidirectional single-phase AC-DC subunits can cooperate with each other to generate three-phase alternating current with a phase difference of 120°, so that the output of three-phase alternating current can be realized through the three energy storage units.

[0392] When charging the device to be charged, the energy storage unit provides the second direct current based on the electrical energy of the battery subunit, and the energy storage module 110 selectively outputs the second direct current to obtain the first direct current through the selection unit 111, the first direct current is converted by the high-power bipolar bidirectional DC-DC subunit to obtain the fourth direct current, and the fourth direct current is used to charge the device to be charged through the charging gun 122, so as to realize high-power charging and fast / ultra-fast charging of the device to be charged. In some examples, the second switch subunits K1, K2 and K3 can be closed in turn in time sharing mode to keep the electrical energy in the three energy storage units consistent.

[0393] It can be understood that under the action of the bidirectional single-phase AC-DC subunit and the bipolar bidirectional DC-DC subunit, the electrical energy of the device to be charged can also be fed to the energy storage module 110 or the alternating current grid, so as to realize the free switching of electrical energy between the device to be charged, the energy storage module 110 and the alternating current grid.

[0394] Example nine, with reference to Figure 22 Compared with the examples shown in Figure 21 The difference is that the sixth power conversion subunit 125 only has a high-voltage positive input end and a high-voltage positive output end, the high-voltage negative input end of the charging gun 122 is directly connected to the second negative power supply end of the energy storage module 110, that is, the negative poles of the charging gun 122 and the energy storage module 110 are shared, and the sixth power conversion subunit 125 can be a unipolar bidirectional DC-DC subunit.

[0395] In the above-mentioned examples eight to nine, the energy storage module 110 and the charging module 120 are connected to the alternating current bus, that is, the charging device 100 adopts the alternating current bus design. When the energy storage module 110 and the charging module 120 are provided as a plurality of modules, the plurality of charging devices 100 share the alternating current bus.

[0396] In the above examples one to nine, the charging device 100 can communicate with external devices, including but not limited to cloud services / monitoring platforms, through the wireless communication module 140, and achieve 4G / 5G communication, etc. The cloud services / monitoring platforms can select appropriate peak and valley periods according to the peak and valley periods of the region where the charging device 100 is located, and issue them to the charging device 100, so that the charging device 100 can achieve peak clipping and valley filling. For example, during the peak period of the alternating current power grid, the alternating current power grid does not charge the energy storage module 110, and during the valley period of the alternating current power grid, the energy storage module 110 is charged by the alternating current power grid.

[0397] It should be noted that the above examples one to nine are only exemplary, and based on the inventive concept of the present application, through reasonable setting of the foregoing architecture, they should all be within the protection scope of the present application.

[0398] In order to further illustrate the implementation manner of the scheme that the rated charging output power of the charging module of the present application is greater than or equal to 290 kilowatts, the following will be described in detail with respect to the battery sub-units.

[0399] In the present application, each energy storage unit can include a battery sub-unit, the battery sub-unit can include one or more single cells, the single cell can include an electrode assembly and an electrolyte, and the electrode assembly includes a positive electrode sheet, a negative electrode sheet and a separator film. The positive electrode sheet includes a positive electrode current collector and a positive electrode film layer arranged on at least one side of the positive electrode current collector, and the positive electrode film layer includes a positive electrode active material. The negative electrode sheet includes a negative electrode current collector and a negative electrode film layer arranged on at least one side of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material. Optionally, the single cell further includes a shell, and the electrode assembly and the electrolyte are contained in the shell. The negative electrode film layer includes at least one film layer, which can be a single layer film layer or at least two layer film layers. Optionally, the negative electrode film layer includes at least two layer film layers. Similarly, the positive electrode film layer can be a single layer film layer or at least two layer film layers. During the charging and discharging process of the single cell, active ions such as lithium ions are inserted and extracted between the positive electrode sheet and the negative electrode sheet, and the electrolyte plays a role in conducting active ions between the positive electrode sheet and the negative electrode sheet.

[0400] The following will be specifically described with respect to the electrolyte, the positive electrode sheet, the negative electrode sheet and the separator film:

[0401] [Electrolyte]

[0402] In some embodiments, the electrolyte includes an electrolyte salt, and the electrolyte salt includes lithium hexafluorophosphate, and the concentration of lithium hexafluorophosphate is in the range of 0.5 mol / L-1.0 mol / L.

[0403] By setting the electrolyte to include lithium hexafluorophosphate at the above concentration, the battery subunit has a high ionic conductivity, thereby improving the charging rate of the charging device, and also has a high interface stability and a high thermal stability; lithium hexafluorophosphate has a small influence on the severity of thermal runaway, so that the battery subunit has a suitable severity of thermal runaway and a low risk of thermal diffusion, thereby making the charging device have a high reliability when the power output is above 350 kW.

[0404] In some embodiments, the electrolyte further includes an organic solvent, and the organic solvent includes a carbonate solvent.

[0405] Optionally, the carbonate solvent includes one or more of ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate, and methyl ethyl carbonate. Further optionally, the carbonate solvent includes one or more of ethylene carbonate, dimethyl carbonate, and methyl ethyl carbonate.

[0406] Further optionally, the mass content of the carbonate solvent in the organic solvent is 10% to 70%, optionally one of 30% to 50% or 10% to 30% or 30% to 70%.

[0407] Illustratively, the mass content of the carbonate solvent in the organic solvent is 10%, 20%, 30%, 31%, 32%, 33%, 34%, 35%, 36%, 37%, 38%, 40%, 45%, 48%, 50%, 55%, 60%, 65%, 70%, or a range formed by any two of the above values. The carbonate solvent at the above mass content can further improve the conductivity of the electrolyte at room temperature, which is conducive to the migration of lithium ions.

[0408] Illustratively, the carbonate solvent includes one or more of ethylene carbonate, dimethyl carbonate, and methyl ethyl carbonate, and the mass content of the carbonate solvent is 30% to 50%.

[0409] Adding the carbonate solvent to the electrolyte can improve various performances of the battery subunit, for example, can improve the charge-discharge efficiency, cycle performance, low-temperature performance, and high-voltage stability of the battery subunit, so that the battery subunit can improve the battery discharge stability at high power output.

[0410] In some embodiments, the electrolyte includes an electrolyte salt, and the electrolyte salt includes lithium hexafluorophosphate, and the concentration of lithium hexafluorophosphate is in the range of 0.5 mol / L to 1.0 mol / L.

[0411] Illustratively, the concentration of lithium hexafluorophosphate can be 0.5 mol / L, 0.6 mol / L, 0.7 mol / L, 0.8 mol / L, 0.9 mol / L, or a range formed by any two of the above values.

[0412] For example, the proportion of lithium hexafluorophosphate can be, but is not limited to, 10%-25% based on the total mass of the electrolyte.

[0413] By setting the electrolyte to include lithium hexafluorophosphate in the above concentration, the battery subunit has a higher ionic conductivity, thereby improving the charging rate of the charging device 100, and also makes the battery subunit have higher interface stability and higher thermal stability; lithium hexafluorophosphate has less effect on the severity of thermal runaway, so that the battery subunit has a suitable thermal runaway severity, and the risk of thermal diffusion is lower, so that the charging device has higher reliability when the power output is above 350kW.

[0414] In some embodiments, the electrolyte salt further includes a fluorine-containing sulfonimide salt, and the concentration of the fluorine-containing sulfonimide salt is in the range of 0.2mol / L-0.5mol / L.

[0415] The fluorine-containing sulfonimide salt can include one or more of lithium bisfluorosulfonimide LiFSI, lithium bis(trifluoromethylsulfonyl)imide LiTFSI.

[0416] Optionally, the lithium salt includes lithium bisfluorosulfonimide LiFSI and lithium hexafluorophosphate LiPF6, the molar concentration of lithium bisfluorosulfonimide LiFSI is 0.2mol / L to 0.5mol / L, and the molar concentration of lithium hexafluorophosphate LiPF6 is 0.5mol / L to 1.0mol / L.

[0417] For example, the molar concentration of lithium bisfluorosulfonimide LiFSI is 0.4mol / L to 0.5mol / L, and the molar concentration of lithium hexafluorophosphate LiPF 66 For example, the molar concentration of lithium bisfluorosulfonimide LiFSI is 0.5mol / L, and the molar concentration of lithium hexafluorophosphate LiPF6 is 0.5mol / L.

[0418] For example, the molar concentration of lithium bisfluorosulfonimide LiFSI is 0.2mol / L, and the molar concentration of lithium hexafluorophosphate LiPF6 is 0.8mol / L.

[0419] For example, the molar concentration of lithium bisfluorosulfonimide LiFSI is 0.2mol / L, and the molar concentration of lithium hexafluorophosphate LiPF6 is 0.8mol / L.

[0420] Optionally, the ratio of the molar concentration of lithium bisfluorosulfonimide LiFSI to the molar concentration of lithium hexafluorophosphate LiPF6 is 0.2 to 1.0, and optionally 0.2 to 0.5. For example, the ratio of the molar concentration of lithium bisfluorosulfonimide LiFSI to the molar concentration of lithium hexafluorophosphate LiPF6 is 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1, or a range composed of any two of the above values.

[0421] In the embodiments of the present application, the types and contents of the inorganic components / lithium salt in the electrolyte are in the meanings known in the art, and can be detected by using the devices and methods known in the art, for example, the qualitative or quantitative analysis of the inorganic components / lithium salt in the electrolyte can be performed by ion chromatography according to the standard JY / T020-1996 "General Ion Chromatography Analysis Method". In the embodiments of the present application, the newly prepared electrolyte can be taken as the sample, the free electrolyte of the fresh battery can be taken as the sample, or the free electrolyte obtained from the battery which has been discharged to the lower limit cut-off voltage so that the charged state of the battery is about 0% SOC by reverse disassembly can be taken as the sample, and the ion chromatography analysis method is used for detection.

[0422] In the embodiments of the present application, the types and contents of the organic components in the electrolyte are in the meanings known in the art, and can be detected by using the devices and methods known in the art, for example, the qualitative and quantitative analysis of the organic components in the electrolyte can be performed by gas chromatography according to the standard GB / T9722-2006 "Chemical Reagents-General Gas Chromatography Method". In the embodiments of the present application, the newly prepared electrolyte can be taken as the sample, the free electrolyte of the fresh battery can be taken as the sample, or the free electrolyte obtained from the battery which has been discharged to the lower limit cut-off voltage so that the charged state of the battery is about 0% SOC by reverse disassembly can be taken as the sample, and the ion chromatography analysis method is used for detection.

[0423] In the embodiments of the present application, after the quantitative and qualitative detection of each component in the electrolyte, each component is classified, the chain carboxylate solvents, carbonate solvents (for example, ethylene carbonate, propylene carbonate, dimethyl carbonate, diethyl carbonate and methyl ethyl carbonate) are taken as the constituent components of the organic solvent, and the mass content of each component is calculated based on 100% of the mass of the organic solvent.

[0424] The carbonate additive (for example, vinylene carbonate, fluoroethylene carbonate), sulfur-containing additive and lithium salt additive are taken as the additives of the electrolyte, and the mass content of each component is calculated based on 100% of the mass of the electrolyte.

[0425] Since the fluorine-containing sulfonimide salt has the characteristics of low viscosity and high ionic conductivity, the electrolyte including the fluorine-containing sulfonimide salt with the above concentration is beneficial to improve the charging rate of the battery subunit, and further improve the charging rate of the charging device.

[0426] In some embodiments, the organic solvent includes a chain carboxylate solvent, and the mass content A of the chain carboxylate solvent based on the total mass of the solvent satisfies: 5%≤A≤75%.

[0427] The chain carboxylate solvent includes a compound with the following structure:

[0428]

[0429] wherein R1 comprises at least one of a hydrogen atom, a C1-C5 alkyl group, or a C1-C5 haloalkyl group, and R2 comprises a C1-C5 alkyl group and / or a C1-C5 haloalkyl group.

[0430] The mass content of the chain carboxylate solvent relative to the mass of the organic solvent is greater than or equal to 5% and less than or equal to 75%, which can be greater than or equal to 10% and less than or equal to 75%, which can be 30% to 70%, which can be 50% to 70%. Exemplarily, the mass content of the chain carboxylate solvent is 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, or a range formed by any two of the above values.

[0431] When the mass content of the chain carboxylate solvent is within the above range, the viscosity of the electrolyte system is relatively small, which is conducive to the migration of lithium ions.

[0432] The chain carboxylate solvent described above has a relatively high conductivity, which is conducive to improving the rapid charging capability of the single cell.

[0433] Optionally, R1 comprises a hydrogen atom, a halogen atom, a C1 to C3 alkyl group, or a C1 to C3 haloalkyl group. Further optionally, R1 comprises a hydrogen atom, a halogen atom, a C1 to C2 alkyl group, or a C1 to C2 haloalkyl group.

[0434] Optionally, R2 comprises a C1 to C3 alkyl group or a C1 to C3 haloalkyl group. Further optionally, R2 comprises a C1 to C2 alkyl group or a C1 to C2 haloalkyl group.

[0435] In each of the above embodiments, the halogen atom comprises one or more of a fluorine atom, a chlorine atom, a bromine atom, and an iodine atom, which can optionally comprise a fluorine atom.

[0436] In each of the above embodiments, the haloalkyl group comprises one or more of a fluoroalkyl group, a chloroalkyl group, a bromoalkyl group, and an iodoalkyl group, which can optionally comprise a fluoroalkyl group.

[0437] Exemplarily, the chain carboxylate solvent comprises one or more of a compound represented by formula I-1 to a compound represented by formula I-8,

[0438]

[0439] The technical solution, the solvent comprises a carboxylate solvent, so that the electrolyte can have a higher ionic conductivity and a relatively low viscosity, which is conducive to further improving the rapid charging performance of the charging device, such as the fast charging performance and / or the super charging performance.

[0440] In some embodiments, the electrolyte has an electrical conductivity of 13 mS / cm to 20 mS / cm, optionally 15 mS / cm to 20 mS / cm at room temperature. For example, the electrolyte has an electrical conductivity of 13 mS / cm, 13.5 mS / cm, 14 mS / cm, 14.5 mS / cm, 15 mS / cm, 15.5 mS / cm, 16 mS / cm, 16.5 mS / cm, 17 mS / cm, 17.5 mS / cm, 18 mS / cm, 18.5 mS / cm, 19 mS / cm, 19.5 mS / cm, 20 mS / cm or a range defined by any two of the above values at room temperature.

[0441] When the electrolyte has an electrical conductivity in the above range at room temperature, for example 25°C, the migration rate of lithium ions in the electrolyte is high, which can further reduce the internal resistance of the single battery cell, thereby reducing heat generation and improving the rapid charging performance of the single battery cell.

[0442] In embodiments of the present application, the electrical conductivity of the electrolyte at room temperature, for example 25°C, is ionic conductivity, which can be detected by devices and methods known in the art, for example, according to industry standard HG-T 4067-2015.

[0443] In some embodiments, the electrolyte has a viscosity of 2.3 mPa·s to 3.5 mPa·s at room temperature. For example, the electrolyte has a viscosity of 2.3 mPa·s, 2.4 mPa·s, 2.5 mPa·s, 2.6 mPa·s, 2.7 mPa·s, 2.8 mPa·s, 2.9 mPa·s, 3.0 mPa·s, 3.1 mPa·s, 3.2 mPa·s, 3.3 mPa·s, 3.4 mPa·s, 3.5 mPa·s or a range defined by any two of the above values.

[0444] When the electrolyte has a viscosity in the above range at room temperature, for example 25°C, the migration rate of lithium ions in the electrolyte is high, which can further reduce the internal resistance of the single battery cell, thereby reducing heat generation and improving the rapid charging performance of the single battery cell.

[0445] In embodiments of the present application, the viscosity of the electrolyte is the meaning known in the art, which can be detected by devices and methods known in the art, for example, according to GB / T 10247-2008.

[0446] In some embodiments, the electrolyte has a density of 1.05 g / mL to 1.35 g / mL at room temperature, for example 25°C. For example, the electrolyte has a density of 1.05 g / mL, 1.10 g / mL, 1.15 g / mL, 1.2 g / mL, 1.25 g / mL, 1.3 g / mL, 1.35 g / mL, or a range defined by any two of the above values.

[0447] When the electrolyte has a density in the above range, the migration rate of lithium ions in the electrolyte is high, which can further reduce the internal resistance of the single battery cell, thereby reducing the heat generation and improving the rapid charging performance of the single battery cell.

[0448] In the embodiments of the present application, the density of the electrolyte has the meaning known in the art and can be detected by using the devices and methods known in the art, for example, by referring to GB / T 2013-2010.

[0449] The electrolyte comprises an organic solvent and an electrolyte salt. The types of the organic solvent and the electrolyte salt are not particularly limited and can be selected according to the actual needs.

[0450] In some embodiments, the electrolyte further comprises an additive. The additive can comprise a negative electrode film-forming additive, a positive electrode film-forming additive, or an additive capable of improving certain performance of the battery, for example, an additive capable of improving the overcharge performance of the battery, an additive capable of improving the high-temperature performance of the battery, an additive capable of improving the low-temperature power performance of the battery, etc.

[0451] In some embodiments, the additive comprises one or more of a carbonate additive, a sulfur-containing additive, and a lithium salt additive, and can optionally comprise at least two of them. The above additives can improve the performance of the interface film on the positive electrode side and / or the negative electrode side, which is beneficial to improving the rapid charging performance of the single battery cell and improving the cycle performance.

[0452] In some embodiments, the mass content of the additive in the electrolyte is 1% to 10%, which can be 2% to 8%, and further can be 3.5% to 8%. For example, the mass content of the additive in the electrolyte is 1%, 2%, 3%, 3.5%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or a range defined by any two of the above values.

[0453] The additive in the above mass content can effectively improve the performance of the interface film on the positive electrode side and / or the negative electrode side, which is beneficial to improving the rapid charging performance of the single battery cell and improving the cycle performance.

[0454] For example, the carbonate additive comprises one or more of vinylene carbonate VC and fluoroethylene carbonate FEC.

[0455] Exemplarily, the sulfur-containing additive comprises one or more of vinyl sulfonate DTD, bis vinyl sulfonate 2-DTD, butylene sulfite BS, 1,3-propane sultone PS, ethylene sulfite ES, and methyl methylene disulfonate MMDS.

[0456] Optionally, the lithium salt additive comprises one or more of lithium difluorophosphate LiPO2F2, lithium difluoro oxalate borate LiDFOB, lithium tetrafluoroborate LiBF4, and lithium bisoxalate borate LiBOB.

[0457] Optionally, the mass content of the vinylene carbonate VC in the electrolyte is 0.5% to 9%, and optionally 2% to 6%.

[0458] Optionally, the mass content of the fluoroethylene carbonate FEC in the electrolyte is 0.1% to 4%, and optionally 0.5% to 3%.

[0459] Optionally, the mass content of the vinylene carbonate VC in the electrolyte is 0.5% to 9%, and the mass content of the fluoroethylene carbonate FEC in the electrolyte is 0.1% to 4%.

[0460] Further optionally, the mass content of the vinylene carbonate VC in the electrolyte is 2% to 6%, and the mass content of the fluoroethylene carbonate FEC in the electrolyte is 0.5% to 3%.

[0461] In some embodiments, the monomer battery cell satisfies 2.45 g / Ah ≤ d / A ≤ 3.5 g / Ah, and optionally 2.45 g / Ah ≤ d / A ≤ 3.3 g / Ah, where d represents the mass of the electrolyte in the monomer battery cell, in units of g, and A represents the rated capacity of the monomer battery cell, in units of Ah. Exemplarily, d / A can be 3.5 g / Ah, 3.3 g / Ah, 3.2 g / Ah, 3.0 g / Ah, 2.8 g / Ah, 2.5 g / Ah, 2.45 g / Ah, or a range formed by any two of the above values.

[0462] d / A can reflect the liquid retention capacity of the electrolyte. When d / A is in the above range, the electrolyte can better infiltrate the positive and negative electrode sheets, and can improve the migration rate of lithium ions in the liquid phase, which is conducive to improving the rapid charging capacity of the monomer battery cell.

[0463] In the embodiments of the present application, d / A of the monomer battery cell can be understood as a liquid retention coefficient, which can be detected by using devices and methods known in the art. For example, GB / T31486-2015 "Electric Performance Requirements and Test Methods for Power Batteries for Electric Vehicles" can be used as an example to illustrate the case where the upper limit voltage of the battery is 3.65V and the discharge cutoff voltage of the battery is 2.0V.

[0464] The monomer cell is charged to 3.65V at 0.33C at 25°C, then charged to 0.05C at constant voltage, and then discharged to 2.0V at 0.33C at constant current, to obtain the capacity A discharged as the denominator, the monomer cell is weighed as M0, then the positive electrode plate, the negative electrode plate, the separator and the electrolyte are disassembled, and the free electrolyte is in a bag, all the solid components are placed in a 60°C oven for more than 4 hours (including but not limited to the positive electrode plate, the negative electrode plate, the separator, and other mechanical parts of the disassembled monomer cell), and then all the components of the monomer cell are weighed as M1, wherein the weight difference between M0 and M1 is taken as the numerator. The liquid retention coefficient is equal to the value obtained by dividing the weight difference d between M0 and M1 by the capacity A.

[0465] [the negative electrode plate]

[0466] In some embodiments, the resistance value of the negative electrode plate can be, but is not limited to, in the range of 0.001Ω-0.01Ω.

[0467] Optionally, the resistance of the negative electrode plate is 0.001Ω to 0.005Ω. Illustratively, the resistance of the negative electrode plate is 0.001Ω, 0.002Ω, 0.003Ω, 0.004Ω, 0.005Ω, 0.006Ω, 0.007Ω, 0.008Ω, 0.009Ω, 0.01Ω, or a range formed by any two of the above values.

[0468] In other examples, the resistance of the negative electrode plate can be in the range of 1mΩ-50mΩ.

[0469] In this way, when the resistance of the negative electrode plate is in the above range, it is beneficial to reduce the internal resistance of the monomer cell, can improve the conductivity of the battery subunit, and further improve the charging rate of the battery subunit, which is beneficial to improve the rapid charging performance of the battery device.

[0470] In the embodiments of the present application, the resistance of the negative electrode plate has the meaning known in the art and can be detected by using devices and methods known in the art, and the detection method is as described above for the resistance test method of the positive electrode plate.

[0471] In some embodiments, the negative active material includes a carbon-based material, and the carbon-based material includes at least one of natural graphite and artificial graphite. Alternatively, the carbon-based material can further include natural graphite. Specifically, the carbon-based material can include graphite particles, or the carbon-based material can include graphite particles and natural graphite.

[0472] Optionally, the carbon-based material is graphite particles. Based on the mass of the graphite particles, the mass percentage of the natural graphite can be greater than that of the artificial graphite.

[0473] The carbon-based material of at least one of natural graphite and artificial graphite is used as the negative active material layer, both of which have good electrical conductivity and high theoretical specific capacity. Natural graphite has high crystallinity and regular layered structure, which is beneficial to the rapid embedding and extraction of lithium ions, thereby improving the charging and discharging efficiency of the battery; artificial graphite can precisely adjust its microstructure and performance by controlling the production process, enhance the cycle stability of the single cell, and prolong the service life of the single cell, thereby prolonging the cycle life and charging stability of the charging device 100 in the scene of high-power charging.

[0474] In some embodiments, the volume average particle size Dv50 of the negative electrode film layer can be, but is not limited to, in the range of 8.2 μm-13.5 μm.

[0475] In the case of using a single-layer film layer for the negative electrode film layer, the negative electrode active material in the negative electrode film layer includes a carbon-based material, and optionally also includes a silicon-based material. In the case of using a single-layer film layer, the volume average particle size Dv50 of the negative electrode active material can be, but is not limited to, 8.2 μm to 13.5 μm. Exemplarily, the volume average particle size Dv50 of the negative electrode active material is 8.2 μm, 8.5 μm, 8.8 μm, 9 μm, 9.2 μm, 9.5 μm, 9.8 μm, 10 μm, 10.2 μm, 10.5 μm, 10.8 μm, 11 μm, 11.2 μm, 11.5 μm, 11.8 μm, 12 μm, 12.2 μm, 12.5 μm, 12.8 μm, 13 μm, 13.2 μm, 13.5 μm, or a range formed by any two of the above values. In other embodiments, the volume average particle size Dv50 of the negative electrode film layer can be between 8.2 μm and 18.5 μm, for example, can be 8.2 μm, 8.5 μm, 8.8 μm, 9 μm, 9.2 μm, 9.5 μm, 9.8 μm, 10 μm, 10.2 μm, 10.5 μm, 10.8 μm, 11 μm, 11.2 μm, 11.5 μm, 11.8 μm, 12 μm, 12.2 μm, 12.5 μm, 12.8 μm, 13 μm, 13.2 μm, 13.5 μm, 14 μm, 15 μm, 16.2 μm, 18 μm, 18.5 μm, or a range formed by any two of the above values.

[0476] In the case of using at least two film layers for the negative electrode film layer, the negative electrode active material in the negative electrode film layer includes a carbon-based material, and optionally also includes a silicon-based material, which can be located in one of the at least two film layers, or in at least two of the at least two film layers. The negative electrode film layer can include two film layers, three film layers, four film layers, or even more film layers.

[0477] The volume average particle size Dv50 of the negative electrode film layer is in a range of 8.2 μm-13.5 μm, which can balance the specific surface area and the compaction density. A smaller particle size can provide a larger specific surface area, increase the reaction sites of lithium ions, and improve the charge-discharge rate performance of the single battery cell; and a proper particle size can have a higher compaction density, reduce the voids between active materials, and improve the energy density of the single battery cell, so that the single battery cell achieves a good balance between the rate performance and the energy density to meet the charging requirements of the charging device 100 at different charging rates.

[0478] In some embodiments, the negative electrode film layer includes a first negative electrode active material layer and a second negative electrode active material layer arranged in a stack, the first negative electrode active material layer is located on a side close to the negative electrode current collector, the volume average particle size Dv50 of the negative electrode active material in the first negative electrode active material layer is 9.5 μm-18.5 μm, and the volume average particle size Dv50 of the negative electrode active material in the second negative electrode active material layer is 7.8 μm-14.3 μm.

[0479] When the volume average particle size Dv50 of the negative electrode active material in the first negative electrode active material layer and the volume average particle size Dv50 of the negative electrode active material in the second negative electrode active material layer are in the above range, on the one hand, the solid-phase transmission path of lithium ions can be shortened, and the rapid charging performance can be improved, and on the other hand, the material is not easy to agglomerate during the preparation process, and the stability of the material can be improved. The negative electrode active material in the second negative electrode active material layer and the negative electrode active material in the first negative electrode active material layer in the above volume average particle size range cooperate, which is conducive to constructing a gradient pore difference between the second negative electrode active material layer and the first negative electrode active material layer, reducing the tortuosity of lithium ion transmission, and improving the rapid charging performance of the battery cell.

[0480] In some embodiments, the negative electrode film layer includes a first negative electrode film layer and a second negative electrode film layer, the first negative electrode film layer is arranged on the surface of the negative electrode current collector, the carbon-based material in the first negative electrode film layer includes graphite particles, the second negative electrode film layer is connected to a side of the first negative electrode film layer away from the negative electrode current collector, the carbon-based material in the second negative electrode film layer includes graphite particles, and the graphite particles in the first negative electrode film layer and the graphite particles in the second negative electrode film layer can be the same or different.

[0481] The interface of the first negative electrode film layer and the second negative electrode film layer can be regular or irregular, and is optionally irregular.

[0482] Optionally, the carbon-based material in the first negative electrode film layer further includes natural graphite.

[0483] The negative electrode film layer includes at least two film layers, and the layered coating is beneficial to improve the rapid charging performance of the single battery cell. In particular, when the first negative electrode film layer and the second negative electrode film layer are different, the pore difference of the negative electrode film layer can be constructed, the tortuosity of lithium ion transmission is reduced, and the rapid charging performance of the single battery cell is improved.

[0484] Optionally, the volume average particle size Dv50 of the negative electrode active material in the first negative electrode film layer is greater than or equal to the volume average particle size Dv50 of the negative electrode active material in the second negative electrode film layer. Further optionally, the volume average particle size Dv50 of the negative electrode active material in the first negative electrode film layer is greater than the volume average particle size Dv50 of the negative electrode active material in the second negative electrode film layer, which is beneficial to improve the compaction density of the negative electrode film layer. When the negative electrode active material includes graphite particles, the volume average particle size Dv50 of the graphite particles in the first negative electrode film layer is greater than or equal to the volume average particle size Dv50 of the graphite particles in the second negative electrode film layer.

[0485] The particle size difference in the first negative electrode film layer and the second negative electrode film layer can improve the rapid charging performance of the single battery cell. Specifically, during the rapid charging process, the overpotential of the second negative electrode film layer is usually high, and the bottleneck of the rapid charging is mainly in the second negative electrode film layer. In the embodiments of the present application, the particle size in the second negative electrode film layer is relatively small, which can shorten the solid-phase transmission path of lithium ions, improve the rapid charging performance, and improve the problem of lithium extraction on the surface of the negative electrode sheet.

[0486] Optionally, the negative electrode active material in the first negative electrode film layer is in a particle form, and the volume average particle size Dv50 thereof is 9.5 μm to 18.5 μm, which can be 9.5 μm to 14.6 μm. Exemplarily, the volume average particle size of the negative electrode active material in the first negative electrode film layer is 9.5 μm, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm, 14.6 μm, 15 μm, 15.5 μm, 16 μm, 16.5 μm, 17 μm, 17.5 μm, 18 μm, 18.5 μm, or a range formed by any two of the above values. When the first negative electrode film layer includes graphite particles, the volume average particle size Dv50 of the graphite particles in the first negative electrode film layer is 9.5 μm to 18.5 μm, which can be 9.5 μm to 14.6 μm.

[0487] When the volume average particle size Dv50 of the negative electrode active material in the first negative electrode film layer is in the above range, on the one hand, the solid-phase transmission path of lithium ions can be shortened, and the rapid charging performance can be improved. On the other hand, the material is not easy to agglomerate during the preparation process, and the stability of the material can be improved.

[0488] Optionally, the volume average particle size Dv50 of the negative active material in the second negative electrode film layer is 7.8 μm to 14.3 μm, or 7.8 μm to 11.3 μm. For example, the volume average particle size Dv50 of the negative active material in the second negative electrode film layer is 7.8 μm, 8.0 μm, 8.2 μm, 8.5 μm, 8.8 μm, 9 μm, 9.2 μm, 9.5 μm, 9.8 μm, 10 μm, 10.2 μm, 10.5 μm, 10.8 μm, 11 μm, 11.3 μm, 11.2 μm, 11.5 μm, 11.8 μm, 12 μm, 12.2 μm, 12.5 μm, 12.8 μm, 13 μm, 13.2 μm, 13.5 μm, 13.8 μm, 14 μm, 14.1 μm, 14.3 μm, or a range defined by any two of the above values. When the second negative electrode film layer comprises graphite particles, the volume average particle size Dv50 of the graphite particles in the second negative electrode film layer is 7.8 μm to 14.3 μm, or 7.8 μm to 11.3 μm.

[0489] When the volume average particle size Dv50 of the negative active material in the second negative electrode film layer is within the above range, on the one hand, the solid-phase transmission path of lithium ions can be shortened, and the rapid charging performance can be improved. On the other hand, the material is less likely to agglomerate during preparation, and the stability of the material can be improved. On the other hand, the negative active material in the second negative electrode film layer and the negative active material in the first negative electrode film layer cooperate to facilitate the construction of a gradient pore difference between the second negative electrode film layer and the first negative electrode film layer, reduce the tortuosity of lithium ion transmission, and improve the rapid charging performance of the single battery cell.

[0490] In the embodiments of the present application, the volume average particle size Dv50 of the negative active material has the meaning known in the art, and can be detected by using the devices and methods known in the art. The detection method is as described above in the volume average particle size Dv50 test method of the positive active material.

[0491] Optionally, the tap density of the carbon-based material in the first negative electrode film layer is less than or equal to the tap density of the carbon-based material in the second negative electrode film layer. The tap density can reflect the filling density of the active material in the film layer. When the tap density of the carbon-based material in the second negative electrode film layer is greater than the tap density of the carbon-based material in the first negative electrode film layer, the second negative electrode film layer is more densely packed, so that the energy density of the single battery cell is improved, and the first negative electrode film layer is relatively less densely packed, and the pores are more abundant, which can improve the rapid charging performance of the single battery cell. When the negative active material comprises graphite particles, the tap density of the graphite particles in the first negative electrode film layer is less than or equal to the tap density of the graphite particles in the second negative electrode film layer.

[0492] Optionally, the tap density of the carbon-based material in the first negative electrode film layer is 0.82 g / cm 3to 1.21g / cm 3 , for example 0.82 g / cm 3 , 0.85g / cm 3 , 0.88g / cm 3 , 0.90g / cm 3 , 0.92g / cm 3 , 0.95g / cm 3 , 0.98g / cm 3 , 1.00g / cm 3 , 1.05g / cm 3 、1.08g / cm 3 , 1.10g / cm 3 , 1.12g / cm 3 , 1.15g / cm 3 , 1.18g / cm 3 , 1.20g / cm 3 , 1.21g / cm 3 When the tap density of the carbon-based material in the first negative electrode film layer is within an appropriate range, the fast charging performance of the single cell can be improved.

[0493] Optionally, the tap density of the carbon-based material in the second negative electrode film layer is 0.90 g / cm 3 Up to 1.25g / cm 3 , for example 0.90g / cm 3 , 0.92g / cm 3 , 0.95g / cm 3 , 0.98g / cm 3 , 1.00g / cm 3 , 1.05g / cm 3 、1.08g / cm 3 , 1.10g / cm 3 , 1.12g / cm 3 , 1.15g / cm 3 , 1.18g / cm 3 , 1.20g / cm 3 , 1.21g / cm 3 , 1.22g / cm 3 , 1.23g / cm 3 , 1.24g / cm 3 ³ , 1.25g / cm 3 When the tap density of the carbon-based material in the second negative electrode film layer is within an appropriate range, the energy density of the single cell can be increased.

[0494] In the embodiments of the present application, the tap density of the material is a meaning known in the art, which can be measured by using instruments and methods known in the art. For example, GB / T 5162-2006 can be referred to, and a powder tap density tester can be used for measurement. The testing instrument can be a Dandong Bitai BT-301.

[0495] Optionally, the ratio of the thickness of the second negative electrode film layer to the thickness of the first negative electrode film layer is 3:7 to 7:3, or 4:6 to 6:4. For example, the ratio of the thickness of the second negative electrode film layer to the thickness of the first negative electrode film layer is 3:7, 4:6, 5:5, 6:4, 7:3, or a range formed by any two of the above values. By adjusting the thickness ratio of the first negative electrode film layer and the second negative electrode film layer, the gradient pore difference between the upper and lower layers can be further increased, the tortuosity of lithium ion transmission can be reduced, and the rapid charging capacity of the single battery cell can be improved.

[0496] In some embodiments, the tap density of the negative electrode film layer of the single battery cell at 100% state of charge is 1.15 g / cm 3 to 1.36 g / cm 3 .

[0497] Optionally, the tap density of the negative electrode film layer of the single battery cell at 100% state of charge is 1.25 g / cm 3 to 1.36 g / cm 3 . For example, the tap density of the negative electrode film layer of the single battery cell at 100% state of charge is 1.15 g / cm 3 , 1.18 g / cm 3 , 1.20 g / cm 3 , 1.22 g / cm 3 , 1.25 g / cm 3 , 1.28 g / cm 3 , 1.3 g / cm 3 , 1.32 g / cm 3 , 1.35 g / cm 3 , 1.36 g / cm 3 , or a range formed by any two of the above values.

[0498] In the embodiments of the present application, the tap density of the negative electrode film layer of the single battery cell at 100% state of charge is a meaning known in the art, which can be detected by using devices and methods known in the art, and the detection method is the same as the tap density test method of the positive electrode film layer described above.

[0499] When the tap density of the negative electrode film layer is in the above range, the energy density of the battery cell can be improved, and since the negative electrode active material in the negative electrode film layer is accumulated more closely, the contact resistance between particles is smaller, which can further reduce the resistance of the electrode sheet, thereby reducing the heat generation.

[0500] In some embodiments, the powder compaction density of the negative active material under a pressure of 20000 N is 1.5 g / cm 3 to 1.85 g / cm 3 , optionally 1.55 g / cm 3 to 1.65 g / cm 3 . For example, the powder compaction density of the negative active material under a pressure of 20000 N is 1.5 g / cm 3 , 1.55 g / cm 3 , 1.6 g / cm 3 , 1.65 g / cm 3 , 1.7 g / cm 3 , 1.75 g / cm 3 , 1.8 g / cm 3³ , 1.85 g / cm 3 , or a range defined by any two of the above values.

[0501] When the powder compaction density of the negative active material under a pressure of 20000 N is within the above range, the energy density of the single battery cell can be improved, and the negative active material in the negative film layer can be more tightly packed, the contact resistance between particles is smaller, which can further reduce the resistance of the electrode sheet, thereby reducing the heat generation.

[0502] In the embodiments of the present application, the powder compaction density of the material is the meaning known in the art, which can be detected by the methods and devices known in the art according to the test standard GB / T24533-2009. For example, a certain amount of negative active material is taken as a sample, added into a mold with a bottom area of 1.327 cm 2² of a UTM7305 electronic pressure testing machine, pressurized to 2000 kg (equivalent to 20000 N), keep pressure for 30 s, then release pressure, keep for 10 s, then record and calculate the powder compaction density of the negative active material under the action of 20000 N force.

[0503] In some embodiments, the charge gram capacity of the negative active material at a 0.1C rate is 350 mAh / g to 480 mAh / g. For example, the charge gram capacity of the negative active material at a 0.1C rate is 350 mAh / g, 355 mAh / g, 360 mAh / g, 365 mAh / g, 370 mAh / g, 375 mAh / g, 380 mAh / g, 385 mAh / g, 390 mAh / g, 395 mAh / g, 400 mAh / g, 410 mAh / g, 420 mAh / g, 430 mAh / g, 440 mAh / g, 450 mAh / g, 460 mAh / g, 470 mAh / g, 480 mAh / g, or a range defined by any two of the above values.

[0504] When the charged gram capacity of the negative active material at the 0.1C rate is in the above range, the energy density of the single battery cell is relatively high.

[0505] In the embodiments of the present application, the charged gram capacity of the negative active material at the 0.1C rate is in the meaning known in the art, which can be detected by using the devices and methods known in the art, and the detection method is as follows: the charged gram capacity of the positive active material at the 0.1C rate is tested.

[0506] In some embodiments, the negative active material layer comprises a carbon-based material, the cycle stability of the carbon-based material is high, and the cycle performance of the single battery cell can be improved. Optionally, the mass fraction of the carbon-based material in the negative active material can be greater than or equal to 80% and less than or equal to 100%.

[0507] The positive active material of the present application is mainly a lithium-containing phosphate system with an olivine structure, and the negative active material is mainly a carbon-based material system. When the two are used together, the cycle performance of the single battery cell is excellent.

[0508] Optionally, the carbon-based material comprises graphite particles, and the graphitization degree of the graphite particles is 92.0% to 94.5%. For example, the graphitization degree of the graphite particles is 92.0%, 92.5%, 93%, 93.5%, 94%, 94.5% or a range formed by any two of the above values.

[0509] When the graphitization degree of the graphite particles is in the above range, the conductivity of the graphite particles is excellent, which can reduce the heat generation of the negative electrode sheet, reduce the heat generation of the single battery cell, and improve the rapid charging performance of the single battery cell.

[0510] In some embodiments, the graphite particles comprise artificial graphite and a carbon coating layer, the artificial graphite comprises secondary particles, the secondary particles comprise a plurality of primary particles, and the carbon coating layer is coated on the surface of the artificial graphite. The carbon in the carbon coating layer is mainly amorphous carbon, which refers to a transition state carbon material with a very low graphitization degree and an approximate amorphous state (or a structure with no fixed shape and periodicity). In the present application, amorphous carbon refers to the product after carbonization treatment of an organic carbon source.

[0511] The artificial graphite comprises secondary particles, the migration path of lithium ions in the artificial graphite is more, and the migration path in the primary particles is shorter, which can improve the migration rate of lithium ions, the carbon coating layer has more end faces and defects, so that the number of sites capable of deintercalating lithium ions increases, and the conductivity of the carbon coating layer is excellent, which can reduce the internal resistance of the negative electrode sheet and the heat generation of the single battery cell.

[0512] Optionally, the mass content of the carbon coating layer is 2% to 5% based on the mass of the graphite particles. Illustratively, the mass content of the carbon coating layer is 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, or a range between any two of the foregoing values.

[0513] When the mass content of the carbon coating layer is within the foregoing range, the internal resistance of the negative electrode sheet can be further reduced, and the heat generation of the single battery cell can be reduced.

[0514] In the embodiments of the present application, the graphite particles can be prepared by methods known in the art, for example, the preparation method includes: providing artificial graphite and an organic carbon source, mixing the two, and then forming a carbon coating layer on at least part of the surface of the artificial graphite particles after carbonization treatment.

[0515] Optionally, the organic carbon source includes one or more of coal tar pitch, petroleum pitch, phenolic resin, and coconut shell. Further optionally, the organic carbon source includes petroleum pitch. Optionally, the softening point of the coal tar pitch and petroleum pitch is below 250°C.

[0516] Optionally, the carbonization treatment temperature is 700°C to 1800°C. Optionally, the carbonization treatment temperature is 1000°C to 1300°C. When the carbonization treatment temperature is within the appropriate range, the organic carbon source can be carbonized, and a coating layer containing amorphous carbon can be formed on at least part of the surface of the artificial graphite.

[0517] Optionally, the carbonization treatment time is 1h to 6h.

[0518] In some embodiments, the negative electrode active material can further include a silicon-based material. The introduction of the silicon-based material can improve the capacity of the negative electrode active material and increase the energy density of the single battery cell.

[0519] Optionally, the mass content of silicon in the silicon-based material is 0.3% to 10.0%, and can be 1% to 6%, based on the mass of the negative electrode active material. Illustratively, the mass content of silicon in the silicon-based material is 0.3%, 0.5%, 0.8%, 1%, 1.2%, 1.5%, 1.8%, 2%, 2.2%, 2.5%, 2.8%, 3%, 3.2%, 3.5%, 3.8%, 4%, 4.2%, 4.5%, 4.8%, 5%, 5.2%, 5.5%, 5.8%, 6%, 6.2%, 6.5%, 6.8%, 7%, 7.2%, 7.5%, 7.8%, 8%, 8.2%, 8.5%, 8.8%, 9%, 9.2%, 9.5%, 9.8%, 10%, or a range between any two of the foregoing values.

[0520] When the mass content of silicon in the silicon-based material is within the foregoing range, the capacity of the negative electrode active material can be improved, and the energy density of the single battery cell can be improved.

[0521] Optionally, the silicon-based material can include at least one of elemental silicon, silicon oxide, silicon-carbon composite, silicon-nitrogen composite, and silicon alloy material.

[0522] In some embodiments, the negative active material can include at least one of tin-based material and lithium titanate in addition to the above-mentioned carbon-based material and optional silicon-based material. The tin-based material can include at least one of elemental tin, tin oxide, and tin alloy material.

[0523] The qualitative and quantitative detection of each substance or element in the present application can be performed by using suitable devices and methods known to those skilled in the art, and the relevant detection methods can refer to domestic and foreign detection standards, domestic and foreign enterprise standards, etc., and those skilled in the art can also adaptively change certain detection steps / instrument parameters from the perspective of detection accuracy to obtain more accurate detection results. One detection method can be used for qualitative or quantitative determination, or several detection methods can be used jointly for qualitative or quantitative determination.

[0524] For example, the negative electrode sheet or the negative active material can be subjected to X-ray powder diffraction test and qualitative analysis by JIS / K0131-1996 X-ray Diffraction Analysis Method General.

[0525] Artificial graphite and natural graphite can be distinguished by SEM cross-sectional SEM images taken by scanning electron microscope SEM, there are gaps between flaky structures in the SEM cross-sectional image of natural graphite, the SEM cross-sectional image of artificial graphite is dense and has no obvious gap, or distinguished by XRD spectrum obtained by X-ray diffraction method, there are obvious 2H phase and 3R phase in the XRD spectrum of natural graphite, and there is only 2H phase in the XRD spectrum of artificial graphite.

[0526] In some embodiments, the powder resistivity of the negative active material is 0.005 Ω•cm to 0.043 Ω•cm, and optionally 0.04 Ω•cm. Illustratively, the powder resistivity of the negative active material can be 0.043 Ω•cm, 0.04 Ω•cm, 0.035 Ω•cm, 0.03 Ω•cm, 0.025 Ω•cm, 0.02 Ω•cm, 0.015 Ω•cm, 0.01 Ω•cm, 0.005 Ω•cm, or a range formed by any two of the above values.

[0527] The relatively low powder resistivity of the negative active material makes the resistance of the negative electrode sheet relatively low, and the single battery cell generates less heat.

[0528] In the embodiments of the present application, the powder resistivity of the negative active material has the meaning known in the art, and can be detected by using devices and methods known in the art, and the detection method is as described above for the powder resistivity test method of the positive active material.

[0529] In some embodiments, after the single battery cell is subjected to 10 cycles of BOL full charge test, the thickness of the first negative electrode film layer is 15-65 μm, for example, 15 μm, 17 μm, 18 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 57 μm, 58 μm, 60 μm, 61 μm, 62 μm, 63 μm, 64 μm, 65 μm, or a range defined by any two of the above values. When the thickness of the first negative electrode film layer is within the above range, the gradient pore difference between the first negative electrode film layer and the second negative electrode film layer can be increased, the tortuosity of lithium ion transmission can be reduced, and the rapid charging capability of the single battery cell can be improved.

[0530] In some embodiments, after the single battery cell is subjected to 10 cycles of BOL full charge test, the thickness of the second negative electrode film layer is 15-65 μm, for example, 15 μm, 17 μm, 18 μm, 20 μm, 25 μm, 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm, 57 μm, 58 μm, 60 μm, 61 μm, 62 μm, 63 μm, 64 μm, 65 μm, or a range defined by any two of the above values. When the thickness of the second negative electrode film layer is within the above range, the gradient pore difference between the first negative electrode film layer and the second negative electrode film layer can be increased, the tortuosity of lithium ion transmission can be reduced, and the rapid charging capability of the single battery cell can be improved.

[0531] In the embodiments of the present application, for example, the upper limit voltage of battery charging is 3.65 V, and the discharge cut-off voltage of the battery is 2.0 V.

[0532] The BOL full charge test procedure is as follows: at 25℃, the battery is charged at a charging rate of 0.33C of the nominal capacity to 3.65 V, then charged at 3.65 V to 0.05C, and then rested for 10 min, then discharged at a discharge rate of 0.33C to 2.0 V, and then rested for 10 min. The above one cycle of charging and discharging is one cycle, and 10 cycles are repeated. Then, the battery is charged at a charging rate of 0.33C of the nominal capacity to 3.65 V, and then charged at 3.65 V to 0.05C, which is the BOL full charge state. In the BOL full charge state, the negative electrode sheet is disassembled, the thickness direction of the cross section of the middle region of the negative electrode sheet is observed using a scanning electron microscope, the interface between the first negative electrode film layer and the second negative electrode film layer is distinguished, the thickness of each layer is measured, for example, the thickness of the first negative electrode film layer at 10 positions is measured, and the average value is calculated as the average thickness of the first negative electrode film layer. The thickness of the second negative electrode film layer at 10 positions is measured, and the average value is calculated as the average thickness of the second negative electrode film layer.

[0533] In some embodiments, after the monomer battery cell is subjected to the End Of Life (EOL) full charge test, the thickness of the first negative electrode film layer is 15 μm to 70 μm, for example, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm, 35 μm, 40 μm, 43 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 66 μm, 67 μm, 68 μm, 69 μm, 70 μm, or a range formed by any two of the above values. When the thickness of the first negative electrode film layer is in the above range, the gradient pore difference between the first negative electrode film layer and the second negative electrode film layer can be increased, the tortuosity of lithium ion transmission can be reduced, and the rapid charging capability of the monomer battery cell can be improved.

[0534] In some embodiments, after the monomer battery cell is subjected to the End Of Life (EOL) full charge test, the thickness of the second negative electrode film layer is 15 μm to 70 μm, for example, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm, 35 μm, 40 μm, 43 μm, 45 μm, 50 μm, 55 μm, 60 μm, 65 μm, 66 μm, 67 μm, 68 μm, 69 μm, 70 μm, or a range formed by any two of the above values. When the thickness of the second negative electrode film layer is in the above range, the gradient pore difference between the first negative electrode film layer and the second negative electrode film layer can be increased, the tortuosity of lithium ion transmission can be reduced, and the rapid charging capability of the monomer battery cell can be improved.

[0535] In the embodiments of the present application, for example, the upper limit voltage of battery charging is 3.65 V, and the discharge cut-off voltage of the battery is 2.0 V.

[0536] The EOL full charge test steps are as follows: at 60°C, charge the battery to 3.65V at a charge rate of 0.33C of the nominal capacity, then charge it to 0.05C at a constant voltage of 3.65V, let it stand for 10 minutes, and then discharge it to 2.0V at a discharge rate of 0.33C, let it stand for 10 minutes. The above charge and discharge cycle is one cycle, and the test is stopped when the battery capacity decays to 80% of the nominal capacity. Then, at 25°C, charge to 3.65V at a constant current of 0.33C and charge to 3.65V at a constant voltage of 0.05C, which is the EOL fully charged state. In the EOL fully charged state, disassemble the negative electrode sheet, and use a tomographic scanning electron microscope to observe the cross-section in the thickness direction of the middle area of ​​the negative electrode sheet. The first negative electrode film layer and the second negative electrode film layer are distinguished according to the interface between the two areas, and the thickness of the two is measured respectively. For example, the thickness of 10 positions of the first negative electrode film layer is measured respectively, and the average value thereof is calculated as the average thickness of the first negative electrode film layer. The thickness of 10 positions of the second negative electrode film layer is measured, and the average value thereof is calculated as the average thickness of the second negative electrode film layer.

[0537] In some embodiments, when the negative electrode film layer adopts a single-layer film layer (as distinguished from the double-layer film layer described above), the negative electrode film layer further includes a lithium-containing binder. Optionally, the mass content of the lithium-containing binder relative to the mass of the negative electrode film layer is 0.1% to 1%. Exemplarily, the mass content of the lithium-containing binder relative to the mass of the negative electrode film layer is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1% or a range consisting of any two of the above values. The lithium element in the lithium-containing binder can exist in the form of ions, which can increase the number of freely moving lithium ions in the negative electrode film layer, shorten the distance that lithium ions diffuse to the surface of the negative electrode film layer, increase the lithium ion deintercalation rate, and improve the fast charging performance of the single cell. Optionally, the negative electrode film layer may further include a negative electrode binder, for example, the negative electrode binder includes at least one of styrene-butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (for example, polyacrylic acid PAA, polymethacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA) and carboxymethyl chitosan (CMCS).

[0538] Optionally, the mass content of lithium in the lithium-containing binder is 3% to 10%. Exemplarily, the mass content of lithium in the lithium-containing binder is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or a range consisting of any two of the above values. The mass content of lithium is calculated based on the mass of the lithium-containing binder. When the mass content of lithium is within the above range, the number of lithium ions that can move freely in the negative electrode film layer is relatively large, which can further shorten the distance that lithium ions diffuse to the surface of the negative electrode film layer, increase the deintercalation rate of lithium ions, and improve the fast charging performance of the single cell.

[0539] Exemplarily, the lithium-containing binder comprises lithium acrylate-acrylonitrile-acrylamide-hydroxyethyl acrylate copolymer, the lithium acrylate-acrylonitrile-acrylamide-hydroxyethyl acrylate copolymer is derived from lithium acrylate monomers, acrylonitrile monomers, acrylamide monomers and hydroxyethyl acrylate monomers, and the molar ratio of the lithium acrylate monomers, the acrylonitrile monomers, the acrylamide monomers and the hydroxyethyl acrylate monomers is 30% to 50%: 15% to 45%: 5% to 20%: 20% to 35%. For example, the molar ratio of the lithium acrylate monomers, the acrylonitrile monomers, the acrylamide monomers and the hydroxyethyl acrylate monomers is 35%: 30%: 15%: 20%, or 40%: 20%: 10%: 30%, or 45%: 15%: 20%: 20%, etc.

[0540] The lithium-containing binder of the above material can provide a certain amount of lithium ions for the negative electrode film layer, improve the rapid charging performance of the single battery, and is not prone to swelling during charging and discharging, so that the structure is stable, and the cycle performance of the negative electrode film layer during rapid charging and discharging is improved.

[0541] In some other embodiments, in the case of adopting at least two film layers for the negative electrode film layer, the negative electrode film layer further comprises a lithium-containing binder.

[0542] Optionally, the first negative electrode film layer further comprises a first lithium-containing binder, and the second negative electrode film layer further comprises a second lithium-containing binder, and the mass content of the first lithium-containing binder relative to the mass of the first negative electrode film layer is less than or equal to the mass content of the second lithium-containing binder relative to the mass of the second negative electrode film layer. Further optionally, the mass content of the first lithium-containing binder relative to the mass of the first negative electrode film layer is less than the mass content of the second lithium-containing binder relative to the mass of the second negative electrode film layer.

[0543] The mass content of the second lithium-containing binder in the second negative electrode film layer is relatively high, and the second lithium-containing binder provides a relatively large amount of freely movable lithium ions for the second negative electrode film layer, which can further improve the rapid charging performance of the single battery.

[0544] Optionally, the mass content of the first lithium-containing binder relative to the mass of the first negative electrode film layer is 0.1% to 1%. Exemplarily, the mass content of the first lithium-containing binder relative to the mass of the first negative electrode film layer is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, or a range formed by any two of the above values. The lithium element in the first lithium-containing binder can exist in the form of ions, which can increase the number of freely movable lithium ions in the negative electrode film layer, shorten the distance of lithium ion diffusion to the surface of the negative electrode film layer, improve the de-intercalation rate of lithium ions, and improve the rapid charging performance of the single battery.

[0545] Optionally, the mass content of lithium element in the first lithium-containing binder is 3% to 10%, which can be 3% to 8%. For example, the mass content of lithium element in the first lithium-containing binder is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or a range formed by any two of the above values. When the mass content of lithium element is in the above range, the number of lithium ions that can freely move in the negative electrode film layer is relatively large, which can further shorten the distance of lithium ion diffusion to the surface of the negative electrode film layer, improve the deintercalation rate of lithium ions, and improve the rapid charging performance of the single battery.

[0546] For example, the first lithium-containing binder includes lithium acrylate-acrylonitrile-acrylamide-hydroxyethyl acrylate copolymer, which is derived from lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer, and the molar ratio of lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer is 30% to 50%: 15% to 45%: 5% to 20%: 20% to 35%. For example, the molar ratio of lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer is 35%: 30%: 15%: 20%, or 40%: 20%: 10%: 30%, or 45%: 15%: 20%: 20%, etc.

[0547] The lithium-containing binder of the above material can provide a certain number of lithium ions for the negative electrode film layer, improve the rapid charging performance of the single battery, and is not prone to swelling during charging and discharging, has a stable structure, and improves the cycle performance of the negative electrode film layer during rapid charging and discharging.

[0548] Optionally, the mass content of the second lithium-containing binder relative to the mass of the second negative electrode film layer is 0.1% to 1%. For example, the mass content of the second lithium-containing binder relative to the mass of the second negative electrode film layer is 0.1%, 0.2%, 0.3%, 0.4%, 0.5%, 0.6%, 0.7%, 0.8%, 0.9%, 1%, or a range formed by any two of the above values. The lithium element in the second lithium-containing binder can exist in the form of ions, which can increase the number of lithium ions that can freely move in the negative electrode film layer, shorten the distance of lithium ion diffusion to the surface of the negative electrode film layer, improve the deintercalation rate of lithium ions, and improve the rapid charging performance of the single battery.

[0549] The first lithium-containing binder and the second lithium-containing binder can be made of the same material or different materials.

[0550] Optionally, the mass content of lithium element in the second lithium-containing binder is 3% to 10%, optionally 3% to 8%. Illustratively, the mass content of lithium element in the second lithium-containing binder is 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, or a range formed by any two of the above values. When the mass content of lithium element is in the above range, the number of lithium ions that can freely move in the negative electrode film layer is relatively large, which can further shorten the distance of lithium ion diffusion to the surface of the negative electrode film layer, improve the deintercalation rate of lithium ions, and improve the rapid charging performance of the single battery cell.

[0551] Illustratively, the second lithium-containing binder includes lithium acrylate-acrylonitrile-acrylamide-hydroxyethyl acrylate copolymer, the lithium acrylate-acrylonitrile-acrylamide-hydroxyethyl acrylate copolymer is derived from lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer, and the molar ratio of lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer is 30% to 50%: 15% to 45%: 5% to 20%: 20% to 35%. For example, the molar ratio of lithium acrylate monomer, acrylonitrile monomer, acrylamide monomer, and hydroxyethyl acrylate monomer is 35%:30%:15%:20%, or 40%, 20%, 10%, 30%, or 45%, 15%, 20%, 20%, etc.

[0552] The lithium-containing binder of the above material can provide a certain amount of lithium ions for the negative electrode film layer, improve the rapid charging performance of the single battery cell, and is not prone to swelling during charging and discharging, has a stable structure, and improves the cycle performance of the negative electrode film layer during rapid charging and discharging.

[0553] In some embodiments, the first negative electrode film layer further includes a negative electrode binder, and the second negative electrode film layer further includes a negative electrode binder. The negative electrode binder in the first negative electrode film layer and the negative electrode binder in the second negative electrode film layer each independently includes at least one of styrene butadiene rubber (SBR), water-soluble unsaturated resin SR-1B, water-based acrylic resin (for example, polyacrylic acid PAA, polymethacrylic acid PMAA, sodium polyacrylate PAAS), polyacrylamide (PAM), polyvinyl alcohol (PVA), sodium alginate (SA), and carboxymethyl chitosan (CMCS).

[0554] In some embodiments, the total content of the first lithium-containing binder and the negative electrode binder in the first negative electrode film layer is greater than the total content of the second lithium-containing binder and the negative electrode binder in the second negative electrode film layer, and the mass content of the first lithium-containing binder relative to the mass of the first negative electrode film layer is less than the mass content of the second lithium-containing binder relative to the mass of the second negative electrode film layer.

[0555] In some embodiments, the negative electrode film layer further optionally comprises a negative electrode conductive agent. The present application does not have a particular limitation on the type of the negative electrode conductive agent, and as an example, the negative electrode conductive agent can comprise at least one of super-p carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. In some embodiments, the mass content of the negative electrode conductive agent is ≤5% based on the total weight of the negative electrode film layer.

[0556] In some embodiments, the negative electrode film layer further optionally comprises a negative electrode binder. In some embodiments, the mass content of the negative electrode binder is ≤5% based on the total weight of the negative electrode film layer.

[0557] In some embodiments, the negative electrode film layer further optionally comprises other auxiliary agents. As an example, the other auxiliary agents can comprise thickening agents, dispersing agents, and the like, such as sodium carboxymethyl cellulose (CMC-Na), PTC thermistor materials, and the like. In some embodiments, the mass content of the other auxiliary agents is ≤2% based on the total weight of the negative electrode film layer.

[0558] In some embodiments, the negative electrode current collector can employ a metal foil or a composite current collector. As an example of the metal foil, at least one foil of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy can be employed. The composite current collector can comprise a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material in the metal material layer can comprise at least one of copper, copper alloy, nickel, nickel alloy, titanium, titanium alloy, silver, and silver alloy. As an example, the polymer material base layer can comprise at least one of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0559] In some embodiments, the ratio CB of the capacity per unit area of the negative electrode film layer to the capacity per unit area of the positive electrode film layer in the single battery cell is 1.05 to 1.30, which can be optionally 1.07 to 1.15. As an example, the ratio CB of the capacity per unit area of the negative electrode film layer to the capacity per unit area of the positive electrode film layer in the single battery cell is 1.05, 1.07, 1.1, 1.12, 1.15, 1.18, 1.2, 1.22, 1.25, 1.28, 1.3, or a range between any two of the above values.

[0560] When the ratio CB of the capacity per unit area of the negative electrode film layer to the capacity per unit area of the positive electrode film layer in the single battery cell is within the above range, there are sufficient sites in the negative electrode film layer for lithium intercalation, which can reduce the risk of lithium precipitation and is conducive to fast charging.

[0561] In the embodiments of the present application, the CB value is of the meaning known in the art and can be detected by using the devices and methods known in the art, for example, the capacity of the unit area of the negative electrode film layer and the capacity of the unit area of the positive electrode film layer are calculated respectively, and the ratio of the two is calculated to obtain the CB value.

[0562] Specifically, taking the battery charging upper limit voltage of 3.65V and the battery discharging cut-off voltage of 2.0V as examples,

[0563] The capacity of the unit area of the positive electrode film layer refers to the actual de-lithium capacity of the positive electrode active material. The test method is as follows: the battery is disassembled in a PRS340 / 11-119-11 Braun glove box, the positive electrode sheet is taken, and a CR2430 type half buckle battery of positive electrode-lithium sheet is assembled. The area of the positive electrode sheet used is a mm 2 , wherein the electrolyte is a solution of 1 mol / L LiPF 66 6 in EC / EMC / DEC=3 / 5 / 2 (mass ratio), and then the assembled half buckle battery is placed for 3h. The test is carried out at 25℃. The capacity of the unit area of the positive electrode film layer is calculated by using 0.1C to charge (Charge) de-lithium in the voltage interval 2.0V to 3.65V, and then using 0.05C to discharge (Discharge) lithium intercalation to 2.0V, and repeating the cycle 2 times. The discharge capacity of the second cycle is taken as Y mAh. The actual battery design positive electrode sheet length is b mm, the width is c mm, and the number of positive electrode active material coated on the positive electrode current collector is d. Then the capacity of the unit area of the positive electrode film layer is Y / (a*b*c*d).

[0564] Specifically, the capacity of the unit area of the negative electrode film layer refers to the actual lithium intercalation capacity of the negative electrode active material. The test method is as follows: the battery is disassembled in a PRS340 / 11-119-11 Braun glove box, the negative electrode sheet is taken, and a CR2430 type half buckle battery of negative electrode-lithium sheet is assembled. The area of the negative electrode sheet used is f mm 2² , wherein the electrolyte is a solution of 1 mol / L LiPF 66 6 in EC / EMC / DEC=3 / 5 / 2 (mass ratio), and then the assembled half buckle battery is placed for 3h. The test is carried out at 25℃. The capacity of the unit area of the positive electrode film layer is calculated by using 0.1C to charge (Charge) de-lithium in the voltage interval 2.0V to 3.65V, and then using 0.05C to discharge (Discharge) lithium intercalation to 2.0V, and repeating the cycle 2 times. The discharge capacity of the second cycle is taken as Y mAh. The actual battery design positive electrode sheet length is b mm, the width is c mm, and the number of positive electrode active material coated on the positive electrode current collector is d. Then the capacity of the unit area of the positive electrode film layer is Y / (a*b*c*d).

[0565] In some embodiments, the single-sided coating weight of the negative electrode film layer is 0.09g / 1540.25mm2 -0.17g / 1540.25mm 2

[0566] Optionally, the single-sided coating weight of the negative electrode film layer is 110 mg / 1540.25 mm 2 to 150 mg / 1540.25 mm 2 . Illustratively, the single-sided coating weight of the negative electrode film layer is 90 mg / 1540.25 mm 2 , 92 mg / 1540.25 mm 2 , 95 mg / 1540.25 mm 2 , 96 mg / 1540.25 mm 2 , 100 mg / 1540.25 mm 2 , 102 mg / 1540.25 mm 2 , 104 mg / 1540.25 mm 2 , 105 mg / 1540.25 mm 2 , 108 mg / 1540.25 mm 2 , 110 mg / 1540.25 mm 2 , 112 mg / 1540.25 mm 2 , 114 mg / 1540.25 mm 2 , 115 mg / 1540.25 mm 2 , 116 mg / 1540.25 mm 2 , 118 mg / 1540.25 mm 2 , 120 mg / 1540.25 mm 2 , 122 mg / 1540.25 mm 2 , 125 mg / 1540.25 mm 2 , 128 mg / 1540.25 mm 2 , 130 mg / 1540.25 mm 2 , 132 mg / 1540.25 mm 2 , 135 mg / 1540.25 mm 2 , 137 mg / 1540.25 mm 2 , 140 mg / 1540.25 mm 2 , 142 mg / 1540.25 mm 2 , 145 mg / 1540.25 mm 2 , 148 mg / 1540.25 mm 2 , 150 mg / 1540.25 mm 2 , 152 mg / 1540.25 mm 2, 155 mg / 154 0.25 mm 2 , 160 mg / 154 0.25 mm 2 , 165 mg / 154 0.25 mm 2 , 170 mg / 154 0.25 mm 2 or a range between any two of the above values.

[0567] In the embodiments of the present application, the single-side coating weight of the negative electrode film layer is in the meaning known in the art, which can be detected by using the devices and methods known in the art, for example, the test method of the single-side coating weight of the film layer is as described above.

[0568] When the single-side coating weight of the negative electrode film layer is in the above range, the heat generation per unit area of the negative electrode tab will not be too large, and the energy density of the battery cell can be improved.

[0569] In some embodiments, the thickness of the negative electrode current collector is 4 μm to 6 μm. For example, the thickness of the negative electrode current collector is 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm or a range between any two of the above values. In other examples, the thickness of the negative electrode current collector is 4 μm to 10 μm, and the thickness of the negative electrode current collector is 4 μm, 4.5 μm, 5 μm, 5.5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm or a range between any two of the above values. The negative electrode current collector can be copper.

[0570] When the thickness of the negative electrode current collector is in the above range, the flow capacity of the negative electrode current collector is excellent, and the energy density of the single battery cell can be improved.

[0571] In the embodiments of the present application, the thickness of the negative electrode current collector is in the meaning known in the art, which can be detected by using the devices and methods known in the art, for example, the thickness of the negative electrode current collector is measured by using a micrometer after the solvent is used to wash the film layer on the surface of the negative electrode current collector.

[0572] The negative electrode film layer is usually formed by coating the negative electrode slurry on the negative electrode current collector, drying and cold pressing. The negative electrode slurry is usually formed by dispersing the negative electrode active material, optional conductive agent, optional binder and other optional additives in a solvent and stirring uniformly. The solvent can be N-methyl pyrrolidone (NMP) or deionized water, but is not limited thereto.

[0573] The negative electrode tab does not exclude other additional functional layers in addition to the negative electrode film layer. For example, in some embodiments, the negative electrode tab of the embodiments of the present application further comprises a negative electrode conductive layer arranged on the surface of the negative electrode current collector and sandwiched between the negative electrode current collector and the negative electrode film layer. In some other embodiments, the negative electrode tab of the embodiments of the present application further comprises a protective layer covering the surface of the negative electrode film layer.

[0574] In some embodiments, the negative electrode tab further comprises a negative electrode conductive layer between the negative electrode film layer and the negative electrode current collector. The negative electrode conductive layer can further improve the conductivity of the negative electrode tab, reduce the heat generation of the negative electrode tab, and thus reduce the heat generation of the single battery cell.

[0575] In some embodiments, the thickness of the negative electrode conductive layer is 0.5 pm to 2 pm. For example, the thickness of the negative electrode conductive layer can be 0.5 pm, 0.8 pm, 1 pm, 1.2 pm, 1.5 pm, 1.6 pm, 1.8 pm, 2 pm, or a range defined by any two of the above values.

[0576] When the thickness of the negative electrode conductive layer is within the above range, the conductivity of the negative electrode tab can be further improved, the heat generation of the negative electrode tab can be reduced, and thus the heat generation of the single battery cell can be reduced, while the energy density of the single battery cell can be improved.

[0577] In the embodiments of the present application, the thickness of the negative electrode conductive layer has the meaning known in the art, can be detected by using the devices and methods known in the art, and can be detected by using the test method of the negative electrode conductive layer described above.

[0578] In some embodiments, the negative electrode conductive layer comprises one or more of a negative electrode conductive agent and a negative electrode binder. The negative electrode conductive agent in the negative electrode conductive layer can improve the conductivity of the negative electrode conductive layer, and thus improve the conductivity of the negative electrode tab and reduce the heat generation of the single battery cell. The negative electrode binder in the negative electrode conductive layer can improve the adhesion between the negative electrode current collector and the negative electrode film layer, and thus improve the structural stability of the negative electrode tab.

[0579] In some embodiments, the negative electrode conductive layer can optionally further comprise other auxiliary agents. For example, the other auxiliary agents can include thickening agents, such as sodium carboxymethyl cellulose (CMC), PTC thermistor materials, and the like.

[0580] Optionally, the mass content of the negative electrode conductive agent in the negative electrode conductive layer is 20% to 40%. For example, the mass content of the negative electrode conductive agent is 20%, 25%, 30%, 35%, 40%, or a range defined by any two of the above values.

[0581] For example, the negative electrode conductive agent comprises one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0582] Optionally, the mass content of the negative electrode binder in the negative electrode conductive layer is 60% to 80%. For example, the mass content of the negative electrode binder is 60%, 65%, 70%, 75%, 80%, or a range defined by any two of the above values.

[0583] Exemplarily, the negative electrode binder comprises one or more of styrene-butadiene rubber SBR, water-soluble unsaturated resin SR-1B, water-based acrylic resin, polyvinyl alcohol, sodium alginate, and carboxymethyl chitosan.

[0584] [Positive electrode sheet]

[0585] In some embodiments, the positive electrode sheet has a resistance value in the range of 0.1 Ω-30 Ω, optionally 0.1 Ω to 5 Ω, further optionally 0.1 Ω to 1 Ω. Exemplarily, the positive electrode sheet has a resistance of 0.1 Ω, 0.5 Ω, 1 Ω, 1.5 Ω, 2 Ω, 2.5 Ω, 3 Ω, 3.5 Ω, 4 Ω, 4.5 Ω, 5 Ω, 5.5 Ω, 6 Ω, 6.5 Ω, 7 Ω, 7.5 Ω, 8 Ω, 8.5 Ω, 9 Ω, 9.5 Ω, 10 Ω, 10.5 Ω, 11 Ω, 11.5 Ω, 12 Ω, 12.5 Ω, 13 Ω, 13.5 Ω, 14 Ω, 14.5 Ω, 15 Ω, 15.5 Ω, 16 Ω, 16.5 Ω, 17 Ω, 17.5 Ω, 18 Ω, 18.5 Ω, 19 Ω, 20 Ω, 21 Ω, 22 Ω, 23 Ω, 24 Ω, 25 Ω, 26 Ω, 27 Ω, 28 Ω, 29 Ω, 30 Ω, or a range between any two of the above values.

[0586] In other examples, the positive electrode sheet has a resistance in the range of 0.01 mΩ-30 Ω.

[0587] In this way, the conductivity of the battery subunit can be improved, and thus the charging performance of the charging device can be improved.

[0588] In some embodiments, the positive electrode film layer of the single battery cell has a compaction density of, but not limited to, 2.5 g / cm 3 -2.8 g / cm 3 , optionally 2.55 g / cm 3 -2.70 g / cm 3 , at 100% state of charge SOC. Exemplarily, the positive electrode film layer of the single battery cell has a compaction density of 2.2 g / cm 3 , 2.50 g / cm 3 , 2.52 g / cm 3 , 2.55 g / cm 3 , 2.56 g / cm 3 , 2.57 g / cm 3 , 2.58 g / cm 3 , 2.60 g / cm 3 , 2.62 g / cm 3 , 2.65 g / cm 3 , 2.68 g / cm 3 , 2.70 g / cm 3 , 2.72 g / cm3 2.75 g / cm3 3 2.78 g / cm3 3 2.80 g / cm3 3 or a range consisting of any two of the aforementioned values.

[0589] When the compaction density of the positive electrode film layer is in the above range, the energy density of the single battery cell can be improved, and because the positive electrode active material in the positive electrode film layer is more densely packed, the contact resistance between particles is smaller, which can further reduce the resistance of the pole piece and thus reduce the heat generation under fast charging. Therefore, by adjusting the compaction density of the positive electrode film layer to a reasonable range, the single battery cell has high energy density and high charging rate performance.

[0590] Optionally, the powder compaction density of the positive electrode active material under 30000N is 2.46 g / cm3 3 2.8 g / cm3 3 . For example, the powder compaction density of the positive electrode active material under 30000N is 2.46 g / cm3 3 2.47 g / cm3 3 2.48 g / cm3 3 2.49 g / cm3 3 2.5 g / cm3 3 2.51 g / cm3 3 2.55 g / cm3 3 2.58 g / cm3 3 2.60 g / cm3 3 2.65 g / cm3 3 2.68 g / cm3 3 2.70 g / cm3 3 2.72 g / cm3 3 2.75 g / cm3 3 2.78 g / cm3 3 2.80 g / cm3 3 or a range consisting of any two of the aforementioned values.

[0591] When the powder compaction density of the positive electrode active material under 30000N is in the above range, the energy density of the single battery cell can be improved, and because the positive electrode active material in the positive electrode film layer can be more densely packed, the contact resistance between particles is smaller, which can further reduce the resistance of the pole piece and thus reduce the heat generation.

[0592] In the embodiments of the present application, the powder compaction density of the material is the meaning known in the art, which can be detected by the methods and devices known in the art according to the test standard GB / T24533-2009. For example, a certain amount of positive active material is taken as a sample, which is added into a mold with a bottom area of 1.327 cm2 of a UTM7305 type electronic pressure testing machine, and is pressed to 3000 kg (equivalent to 30000 N), and is kept for 30 s, then is unloaded, and is kept for 10 s, then the powder compaction density of the positive active material under the action of 30000 N is recorded and calculated. 2

[0593] In some embodiments, the single-side coating weight of the positive electrode film layer is 0.2 g / 1540.25 mm 2 to 0.37 g / 1540.25 mm 2 , which can be 240 mg / 1540.25 mm 2 to 330 mg / 1540.25 mm 2 . Exemplarily, the single-side coating weight of the positive electrode film layer is 200 mg / 1540.25 mm 2 , 210 mg / 1540.25 mm 2 , 220 mg / 1540.25 mm 2 , 230 mg / 1540.25 mm 2 , 240 mg / 1540.25 mm 2 , 250 mg / 1540.25 mm 2 , 260 mg / 1540.25 mm 2 , 270 mg / 1540.25 mm 2 , 280 mg / 1540.25 mm 2 , 290 mg / 1540.25 mm 2 , 300 mg / 1540.25 mm 2 , 310 mg / 1540.25 mm 2 , 320 mg / 1540.25 mm 2 , 330 mg / 1540.25 mm 2 , 340 mg / 1540.25 mm 2 , 350 mg / 1540.25 mm 2 , 360 mg / 1540.25 mm 2 , 370 mg / 1540.25 mm 2 or a range composed of any two of the above values.

[0594] ​When the single-sided coating weight of the positive electrode film layer is within the above range, the heat generation per unit area of the positive electrode tab will not be too large, and the energy density and the charge rate performance of the single battery cell can be improved.

[0595] In the embodiments of the present application, the compaction density of the positive electrode film layer of the single battery cell at 100% state of charge (SOC) can be detected by the following method. The positive electrode tab is removed from the single battery cell at 100% SOC, and the compaction density of the positive electrode film layer is measured. For example, the single-sided coated positive electrode tab (if it is a double-sided coated tab, the positive electrode film layer on one side can be wiped off first) is punched into a small disc with an area of S1, weighed, recorded as M1, and its thickness H1 is measured. Then the positive electrode film layer of the above weighed positive electrode tab is wiped off, the weight of the positive electrode current collector is measured, recorded as M0, and its thickness H0 is measured. The single-sided coating weight of the positive electrode film layer = (the weight of the positive electrode tab M1 - the weight of the positive electrode current collector M0) / S1, the thickness of the positive electrode film layer = the thickness of the positive electrode tab H1 - the thickness of the positive electrode current collector H0, and the compaction density of the positive electrode film layer = the single-sided coating weight of the positive electrode film layer / the thickness of the positive electrode film layer.

[0596] In some embodiments, the thickness of the positive electrode current collector is 10-15 μm, which can be 12-15 μm. For example, the thickness of the positive electrode current collector is 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 12.5 μm, 13 μm, 13.5 μm, 14 μm, 14.5 μm, 15 μm, or a range defined by any two of the above values.

[0597] The positive electrode current collector can be aluminum.

[0598] When the thickness of the positive electrode current collector is within the above range, the flow capacity of the positive electrode current collector is excellent, and the single battery cell has a high energy density.

[0599] In the embodiments of the present application, the thickness of the positive electrode film layer and the positive electrode current collector has the meaning known in the art, and can be detected by the devices and methods known in the art. For example, the thickness of the positive electrode tab is measured by using a micrometer, the film layer on the surface of the positive electrode current collector is removed, the thickness of the positive electrode current collector is measured, the thickness of the positive electrode film layer is the thickness of the positive electrode tab minus the thickness of the positive electrode current collector when the positive electrode film layer is single-sided coated, and the thickness of the positive electrode film layer is (the thickness of the positive electrode tab minus the thickness of the positive electrode current collector) / 2 when the positive electrode film layer is double-sided coated.

[0600] The positive electrode film layer is usually formed by coating the positive electrode slurry on the positive electrode current collector, drying, and cold pressing. The positive electrode slurry is usually formed by dispersing the positive electrode active material, the optional conductive agent, the optional binder, and any other components in a solvent and stirring uniformly. The solvent can be N-methyl pyrrolidone (NMP), but is not limited thereto.

[0601] The positive electrode tab does not exclude other additional functional layers besides the positive electrode film layer. For example, in some embodiments, the positive electrode tab of the embodiments of the present application further comprises a positive electrode conductive layer sandwiched between the positive electrode current collector and the positive electrode film layer, arranged on the surface of the positive electrode current collector. In some other embodiments, the positive electrode tab of the embodiments of the present application further comprises a protective layer covering the surface of the positive electrode film layer.

[0602] In some embodiments, the ratio of the thickness of the positive electrode current collector to the thickness of the single-sided positive electrode film layer is 0.05 to 0.3. Illustratively, the ratio of the thickness of the positive electrode current collector to the thickness of the single-sided positive electrode film layer is 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.12, 0.15, 0.18, 0.2, 0.22, 0.25, 0.28, 0.3, or a range formed by any two of the above values.

[0603] When the ratio of the thickness of the positive electrode current collector to the thickness of the single-sided positive electrode film layer is within the above range, the rapid charging capability and energy density of the single battery cell can be improved.

[0604] In some embodiments, the powder resistivity of the positive electrode active material is 1 Ω•cm to 27.5 Ω•cm, optionally, less than or equal to 20 Ω•cm, optionally, less than or equal to 11 Ω•cm. Illustratively, the powder resistivity of the positive electrode active material can be 27.5 Ω•cm, 20 Ω•cm, 19 Ω•cm, 18 Ω•cm, 17 Ω•cm, 16 Ω•cm, 15 Ω•cm, 14 Ω•cm, 13 Ω•cm, 12 Ω•cm, 11 Ω•cm, 10 Ω•cm, 9 Ω•cm, 8 Ω•cm, 7 Ω•cm, 6 Ω•cm, 5 Ω•cm, 4 Ω•cm, 3 Ω•cm, 2 Ω•cm, 1 Ω•cm, or a range formed by any two of the above values.

[0605] The relatively low powder resistivity of the positive electrode active material makes the resistance of the positive electrode tab relatively low, and the single battery cell generates less heat.

[0606] In the embodiments of the present application, the powder resistivity of the material is the meaning known in the art, which can be detected by methods and devices known in the art, for example, according to the test standard GB / T30835-2014, using a PRCD1100 powder resistivity meter for testing.

[0607] In some embodiments, the cathode active material has a charge gram capacity at 0.1C rate of 150 mAh / g to 170 mAh / g, optionally 157 mAh / g to 170 mAh / g. Illustratively, the cathode active material has a charge gram capacity at 0.1C rate of 150 mAh / g, 151 mAh / g, 152 mAh / g, 153 mAh / g, 154 mAh / g, 155 mAh / g, 156 mAh / g, 157 mAh / g, 158 mAh / g, 159 mAh / g, 160 mAh / g, 161 mAh / g, 162 mAh / g, 163 mAh / g, 164 mAh / g, 165 mAh / g, 166 mAh / g, 167 mAh / g, 168 mAh / g, 169 mAh / g, 170 mAh / g, or a range defined by any two of the foregoing values.

[0608] When the cathode active material has a charge gram capacity at 0.1C rate in the above range, the energy density of the single battery cell is relatively high.

[0609] In the embodiments of the present application, the gram capacity of the active material has the meaning known in the art and can be tested using devices and methods known in the art. The test method for the first coulombic efficiency and the first discharge specific capacity in Appendix G of the national standard GB / T 24533-2019 can be used. A half-buckle type battery is assembled using lithium metal as the negative electrode and the sample tab containing the above material as the positive electrode. The half-buckle type battery is tested on a battery tester or other equivalent performance testing device at 23°C ± 2°C. The discharge capacity is obtained by 0.1C rate charging and discharging, and then the capacity is divided by the mass of the active material of the tab to obtain the charge gram capacity parameter.

[0610] In some embodiments, the cathode active material includes a lithium-containing phosphate, and the lithium-containing phosphate includes phosphate particles and a coating layer. The coating layer is coated on the surface of the phosphate particles, and the coating layer contains one or more of C, Fe, Ti, Zr, Hf, Ge, and Sn.

[0611] The phosphate particles coated with the coating layer on the surface can improve the electrical conductivity of the lithium-containing phosphate with an olivine structure, reduce the powder resistivity of the material, and be beneficial to improving the migration rate of lithium ions, improving the rapid charging capacity of the battery, and reducing the heat generation of the single battery cell.

[0612] The mass ratio of the olivine-structured lithium-containing phosphate in the positive electrode active material can be greater than or equal to 80% and less than or equal to 100%. It can be considered that the positive electrode active material of the present application is an olivine-structured lithium-containing phosphate system. When the mass ratio of the olivine-structured lithium-containing phosphate is less than 100%, the positive electrode active material can also include commonly used positive electrode active materials, for example, can include but is not limited to at least one of lithium-containing transition metal oxides. Examples of lithium-containing transition metal oxides can include but are not limited to at least one of lithium cobalt oxide, lithium nickel oxide, lithium manganese oxide, lithium nickel cobalt oxide, lithium manganese cobalt oxide, lithium nickel manganese oxide, lithium nickel cobalt manganese oxide, lithium nickel cobalt aluminum oxide, and their respective modified compounds.

[0613] Optionally, the mass ratio of the olivine-structured lithium-containing phosphate in the positive electrode active material is 100%.

[0614] In some embodiments, the phosphate particles include a compound of the general formula Li x1 A y1 Me a M b P 1-c X c Y z , wherein 0.5≤x1≤1.3, 0≤y1≤1.3, and 0.9≤x1+y1≤1.3, 0.9≤a≤1.5, 0≤b≤0.5, and 0.9≤a+b≤1.5, 0≤c≤0.5, 3≤z≤5, A includes one or more of Na, K, Mg, Me includes one or more of Mn, Fe, Co, Ni, M includes one or more of B, Mg, Al, Si, P, S, Ca, Sc, Ti, V, Cr, Cu, Zn, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Te, Ba, Ta, W, Yb, La, Ce, X includes one or more of S, Si, Cl, B, C, N, and Y includes one or more of O, F. The cycle stability of the phosphate particles is relatively excellent, which is beneficial to improve the cycle performance of the single battery cell.

[0615] Exemplarily, the chemical elements in the phosphate particles at least include Li, Fe, P, Al, Ti, and the mass ratio of each element is (3-4):(30-35):(15-20):(0.01-0.1):(0.1-0.5) in turn.

[0616] Exemplarily, the phosphate particles include one or more of LiFePO4, LiMnPO4, LiNiPO4, and LiCoPO4. The charge and discharge process of a single cell is accompanied by the deintercalation and consumption of active ions such as Li, and the molar content of Li in the single cell is different when discharged to different states. In the enumeration of positive electrode active materials LiFePO4, LiMnPO4, LiNiPO4, LiCoPO4, etc., the molar content of Li is the initial state of the material, that is, the state before feeding. The positive electrode active material is used in the battery system, and after the charge and discharge cycle, the molar content of Li may change. In the enumeration of positive electrode active materials LiFePO4, LiMnPO4, LiNiPO4, LiCoPO4, etc. in the embodiment of the present application, the molar content of oxygen O is only a theoretical state value. The release of lattice oxygen will cause the molar content of oxygen O to change. In practice, the molar content of oxygen O will fluctuate. The above situations are all within the scope of protection of the present application.

[0617] In some embodiments, the coating layer comprises a 3-d Fe 2-d M 2d (PO x2 ) y2 The fast ion conductor M2 includes one or more elements selected from Ti, Zr, Hf, Ge and Sn, 0≤d≤1, 0<x2<5, 0<y2<4.

[0618] Exemplarily, the fast ion conductor is a material having a NASICON structure, such as one or more of lithium iron titanium phosphate Li2FeTi(PO4)3, lithium iron zirconium phosphate Li2FeZr(PO4)3, and lithium iron tin phosphate Li2FeSn(PO4)3.

[0619] Fast ion conductors with a NASICON structure are materials with ultrafast ion conduction capabilities. They possess abundant three-dimensional lithium ion diffusion and transport channels, and exhibit advantages such as high ion conduction efficiency and strong structural stability during multiple delithiation and insertion processes. Coating phosphate particles with a fast ion conductor containing a NASICON structure can significantly increase the lithium ion transport rate at the positive electrode during multiple delithiation and insertion processes, improve the ionic conductivity of the positive electrode active material, and enhance the rapid charging capability of the individual battery cells. Furthermore, it can increase the specific capacity and the energy density of the corresponding individual battery cells.

[0620] In some embodiments, the coating layer further includes carbon.

[0621] The carbon element and the fast ion conductor can be arranged in layers, for example, the carbon element as an independent carbon coating layer and the fast ion conductor as an independent fast ion conductor layer. The carbon coating layer can be coated on the surface of the phosphate particles, and the fast ion conductor layer is located on the surface of the carbon coating layer, that is, the fast ion conductor layer is located on the side of the carbon coating layer away from the phosphate particles. Alternatively, the fast ion conductor layer can be coated on the surface of the phosphate particles, and the carbon coating layer is located on the surface of the fast ion conductor layer, that is, the carbon coating layer is located on the side of the fast ion conductor layer away from the phosphate particles. Of course, the carbon element and the fast ion conductor can also be arranged in the same layer.

[0622] Optionally, the carbon coating layer can be coated on the surface of the fast ion conductor layer by a carbonization process of an organic carbon source (for example, glucose, polyethylene glycol, etc.). The carbon coating layer can partially coat the fast ion conductor layer or completely coat the fast ion conductor layer. The arrangement of the carbon coating layer can significantly improve the electronic conductivity of the phosphate particles, compensate for the poor electronic conductivity of the phosphate particles, and improve the energy density of the single battery.

[0623] Specifically, the arrangement of the carbon coating layer has the following advantages for the positive electrode active material of the application:

[0624] The carbon coating layer in the positive electrode active material of the application provides a suitable channel for the transmission of electrons, can significantly improve the conduction rate of electrons in the process of multiple delithiation and lithiation, improve the electronic conductivity of the lithium-containing phosphate, and improve the charging capacity and energy density of the corresponding single battery.

[0625] The carbon coating layer of the positive electrode active material of the application has a loose and porous structure, which enables the electrolyte to fully and effectively contact the lithium-containing phosphate, thereby improving the transmission rate of lithium ions at the phase interface and the charging capacity of the single battery.

[0626] Coating a carbon coating layer on the surface of the lithium-containing phosphate not only improves the electronic conductivity of the lithium-containing phosphate, but also improves the structural stability of the positive electrode active material, effectively alleviates the iron dissolution phenomenon of the positive electrode active material during long-term storage and cyclic use of the single battery, and improves the cycle life of the single battery.

[0627] The positive electrode active material of the application uses lithium-containing phosphate as a substrate, fully utilizes the advantages of low cost, high reliability, and good cycle stability of lithium-containing phosphate, and solves the disadvantages of poor electronic conductivity and ionic conductivity by using the coating layer (fast ion conductor layer and carbon coating layer). The single battery prepared from the positive electrode active material of the application can improve the energy density of the single battery under the premise of excellent cycle performance.

[0628] In the embodiments of the present application, the content of elements in the positive electrode active material is in the meaning known in the art, which can be detected by using the devices and methods known in the art, for example, referring to EPA 6010D-2014, tested by inductively coupled plasma atomic emission spectrometry, and determined by plasma atomic emission (ICP-OES, instrument model: Thermo ICAP7400). After disassembling the positive electrode sheet from the single battery cell discharged to 0% state of charge SOC, washing and drying with DMC, and removing impurities by high-temperature calcination, 0.4g of the positive electrode active material is weighed, 10ml (50% concentration) aqua regia is added thereto. Then it is placed on a 180℃ flat plate for 30min. After digestion on the flat plate, it is diluted to a volume of 100ml, and the quantitative test is performed by the standard curve method.

[0629] In some embodiments, the graphitization degree of the positive electrode active material is 0.15 to 0.32, which can be 0.19 to 0.26. Illustratively, the graphitization degree of the positive electrode active material is 0.15, 0.16, 0.17, 0.18, 0.19, 0.20, 0.21, 0.22, 0.23, 0.24, 0.25, 0.26, 0.27, 0.28, 0.29, 0.30, 0.31, 0.32, or a range consisting of any two of the above values.

[0630] When the graphitization degree of the positive electrode active material is in the above range, it is beneficial to improve the conductivity of the positive electrode active material and reduce the heat generation of the positive electrode sheet, thereby reducing the heat generation of the single battery cell.

[0631] In the embodiments of the present application, the higher the graphitization degree of the material, the lower the degree of disorder, which can be tested according to the test standard JIS / K 0131-1996 "General method for X-ray diffraction analysis".

[0632] In some embodiments, the mass content of carbon element in the olivine-structured lithium-containing phosphate is 1% to 2%, and the specific surface area of the olivine-structured lithium-containing phosphate is 5m 2 / g to 18m 2 / g.

[0633] Alternatively, the mass content of carbon element in the olivine-structured lithium-containing phosphate is 1% to 2%, and the specific surface area of the olivine-structured lithium-containing phosphate is 7.5m 2 / g to 14m 2 / g.

[0634] Illustratively, the mass content of carbon element in the olivine-structured lithium-containing phosphate is 1%, 1.1%, 1.2%, 1.3%, 1.4%, 1.5%, 1.6%, 1.7%, 1.8%, 1.9%, 2%, or a range consisting of any two of the above values.

[0635] Exemplarily, the specific surface area of the lithium-containing phosphate with olivine structure is 5m 2 / g, 6m 2 / g, 7m 2 / g, 8m 2 / g, 9m 2 / g, 10m 2 / g, 11m 2 / g, 12m 2 / g, 13m 2 / g, 14m 2 / g, 15m 2 / g, 16m 2 / g, 17m 2 / g, 18m 2 / g or a range formed by any two of the above values.

[0636] The carbon element mainly exists in the material in the form of a carbon coating layer, the carbon coating layer is loose and porous, which is beneficial to improve the specific surface area of the material, and is more beneficial to the effective contact between the electrolyte and the phosphate particles and the transmission of lithium ions at the phase interface. In addition, when the mass content of the carbon element is in the above range, the conductivity of the lithium-containing phosphate with olivine structure can be significantly improved, which is beneficial to improve the ionic conductivity and electronic conductivity of the lithium-containing phosphate with olivine structure, and can improve the rapid charging capacity and energy density of the single cell.

[0637] In the embodiments of the present application, the specific surface area of the material has the meaning known in the art and can be detected by using the devices and methods known in the art, for example, the specific surface area is detected according to the test standard GB / T 19587-2017, the positive electrode active material is used as a sample, and the specific surface area is tested by using a Tri-Star 3020 type specific surface area pore size analyzer of the Micromeritics company in the United States.

[0638] In some embodiments, the volume distribution particle size of the positive electrode active material satisfies: 1µm≤Dv50≤2µm, 0.4µm≤Dv10≤0.7µm.

[0639] Exemplarily, the Dv50 of the positive electrode active material can be 1µm, 1.1µm, 1.15µm, 1.2µm, 1.25µm, 1.3µm, 1.35µm, 1.4µm, 1.45µm, 1.5µm, 1.55µm, 1.6µm, 1.65µm, 1.7µm, 1.75µm, 1.8µm, 1.85µm, 1.9µm, 1.95µm, 2µm or a range formed by any two of the above values.

[0640] Exemplarily, the Dv10 of the positive electrode active material can be 0.4 µm, 0.45 µm, 0.5 µm, 0.55 µm, 0.6 µm, 0.65 µm, 0.7 µm, or a range formed by any two of the above values.

[0641] The particle size of the positive electrode active material is relatively small, the path of lithium ion deintercalation in the positive electrode active material is short, and the heat production is less. Moreover, the particle size of the positive electrode active material is not too small, and agglomeration basically does not occur in the process of preparation, so that the performance of the positive electrode active material is stable.

[0642] In the embodiments of the present application, the volume average particle size Dv50 of the material refers to the particle size corresponding to 50% in the volume distribution, and the volume average particle size Dv10 of the material refers to the particle size corresponding to 10% in the volume distribution. The detection can be performed by using devices and methods known in the art, for example, the positive electrode active material is taken as a sample, the Dv50 and Dv10 of the particles are tested by a Mastersizer 2000E laser particle size analyzer according to the test standard GB / T 19077-2016.

[0643] When the positive electrode active material includes other materials in addition to the lithium-containing phosphate with olivine structure, the volume distribution particle size of the positive electrode active material refers to the volume distribution particle size of all the positive electrode active materials.

[0644] In some embodiments, the lithium-containing phosphate with olivine structure is in a particulate form, the lithium-containing phosphate with olivine structure includes secondary particles, the secondary particles include a plurality of primary particles, and the average particle size of the primary particles is 200 nm to 500 nm. Exemplarily, the average particle size of the primary particles is 200 nm, 220 nm, 250 nm, 280 nm, 300 nm, 320 nm, 350 nm, 380 nm, 400 nm, 420 nm, 450 nm, 480 nm, 500 nm, or a range formed by any two of the above values.

[0645] The average particle size of the primary particles is relatively small, the path of lithium ion deintercalation in the positive electrode active material is short, and the heat production is less.

[0646] In the embodiments of the present application, the secondary particle refers to an agglomerated particle formed by aggregation of two or more primary particles. The primary particles and the secondary particles can be easily distinguished by experimental means (such as using a scanning electron microscope to take SEM images), and the average particle size of the primary particles can be obtained by SEM image testing. The SEM test parameters can be set as follows: working voltage (EHT) is 10.00 kV, InLens detector is used, working distance is 4.6 mm, and magnification is 1000X.

[0647] In some embodiments, the positive electrode film layer further comprises one or more of a ternary material, lithium phosphate, lithium dihydrogen phosphate, lithium sulfate, lithium sulfite, lithium molybdate, lithium oxalate, lithium titanate, lithium tetraborate, lithium metasilicate, lithium metamanganate, lithium tartrate, trilithium citrate, lithium nickelate, and lithium ferrite. The above-mentioned materials can serve as a lithium supplement, which can supplement lithium ions for the positive electrode film layer, make up for the irreversible loss of lithium ions in the system, improve the capacity, and thus improve the energy density of the single battery cell.

[0648] Optionally, the ternary material comprises Li x3 A y3 Ni a3 Co b3 Mn c M3 (1-a3-b3-c3) Y3 z3 , wherein 0 < x3 < 2.1, 0 < y3 < 2.1, and 0.9 < x3 + y3 < 2.1, 0 < a3 < 1, 0 < b3 < 1, 0 < c3 < 1, and 0.1 < a3 + b3 + c3 < 1, 1.8 < z3 < 3.5, A comprises one or more of Na, K, Mg, M3 comprises one or more of B, Mg, Al, Si, P, S, Ca, Sc, Ti, V, Cr, Fe, Cu, Zn, Sr, Y, Zr, Nb, Mo, Cd, Sn, Sb, Te, Ba, Ta, W, Yb, La, Ce, and Y3 comprises one or more of O, F.

[0649] Exemplarily, the ternary material comprises LiNi 1 / 3 Co 1 / 3 Mn 1 / 3 O2 (NCM333), LiNi 0.5 Co 0.2 Mn 0.3 O2 (NCM523), LiNi 0.6 Co 0.2 Mn 0.2 O2 (NCM622), LiNi 0.8 Co 0.1 Mn 0.1 O2 (NCM811), LiNi 0.80 Co 0.15 Al 0.05 O2.

[0650] In some embodiments, the mass content of the lithium supplement in the positive electrode film layer is 0.5% to 5%, for example, 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 4.5%, 5%, or a range between any two of the foregoing values. When the mass content of the lithium supplement is within the foregoing range, the lithium supplement can supplement lithium ions to the positive electrode film layer, compensate for the irreversible loss of lithium ions in the system, and improve the capacity, thereby improving the energy density of the single battery cell.

[0651] The lithium supplement can be in the same layer as the positive electrode active material, or in different layers. When the lithium supplement and the positive electrode active material are in different layers, the lithium supplement can be in a lithium supplement layer, and the positive electrode active material can be in a positive electrode active material layer, in other words, the positive electrode film layer includes the lithium supplement layer and the positive electrode active material layer. The positive electrode active material layer can be disposed on at least one side of the positive electrode current collector, and the lithium supplement layer can be between the positive electrode active material layer and the positive electrode current collector. Alternatively, the lithium supplement layer can be disposed on at least one side of the positive electrode current collector, and the positive electrode active material layer can be between the lithium supplement layer and the positive electrode current collector. Alternatively, the lithium supplement layer can be between the positive electrode active material layer and the positive electrode current collector, and the lithium supplement in the lithium supplement layer can be gradually released into the system during the cyclic charging and discharging of the single battery cell, thereby compensating for the loss of lithium in the battery system.

[0652] In some embodiments, the positive electrode film layer optionally further includes a positive electrode conductive agent. The type of positive electrode conductive agent is not particularly limited in the embodiments of the present application, and as an example, the positive electrode conductive agent includes at least one of super conductive carbon, conductive graphite, acetylene black, carbon black, ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers.

[0653] In some embodiments, the mass content of the positive electrode conductive agent is ≤5% based on the mass of the positive electrode film layer.

[0654] In some embodiments, the positive electrode film layer optionally further includes a positive electrode binder. The type of positive electrode binder is not particularly limited in the embodiments of the present application, and as an example, the positive electrode binder can include at least one of polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, polyacrylic acid, and a fluorine-containing acrylic ester resin. In some embodiments, the mass content of the positive electrode binder is ≤5% based on the mass of the positive electrode film layer.

[0655] In some embodiments, the positive current collector can employ a metal foil or a composite current collector. As an example of the metal foil, at least one of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy can be employed. The composite current collector can include a polymer material base layer and a metal material layer formed on at least one surface of the polymer material base layer. As an example, the metal material of the metal material layer can include at least one of aluminum, an aluminum alloy, nickel, a nickel alloy, titanium, a titanium alloy, silver, and a silver alloy. As an example, the polymer material base layer can include at least one of polypropylene (PP), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polystyrene (PS), and polyethylene (PE).

[0656] In some embodiments, the positive electrode tab further includes a positive conductive layer between the positive film layer and the positive current collector. The positive conductive layer can further improve the conductivity of the positive electrode tab, reduce the heat generation of the positive electrode tab, and thus reduce the heat generation of the single battery cell.

[0657] In some embodiments, the positive conductive layer has a thickness of 0.5 μm to 2 μm. For example, the positive conductive layer has a thickness of 0.5 μm, 0.8 μm, 1 μm, 1.2 μm, 1.5 μm, 1.6 μm, 1.8 μm, 2 μm, or a range defined by any two of the above values.

[0658] When the thickness of the positive conductive layer is within the above range, the conductivity of the positive electrode tab can be further improved, the heat generation of the positive electrode tab can be reduced, and thus the heat generation of the single battery cell can be reduced, while the energy density of the single battery cell can be improved.

[0659] In the embodiments of the present application, the thickness of the positive conductive layer has the meaning known in the art and can be detected by using the devices and methods known in the art, for example, by performing a tomographic scan on the positive electrode tab to directly measure the thickness of the positive conductive layer.

[0660] In some embodiments, the positive conductive layer includes one or more of a positive conductive agent and a positive binder.

[0661] Optionally, the positive conductive agent has a mass content of 30% to 50% in the positive conductive layer. For example, the positive conductive agent has a mass content of 30%, 35%, 40%, 45%, 50%, or a range defined by any two of the above values.

[0662] For example, the positive conductive agent includes one or more of superconducting carbon, conductive graphite, acetylene black, carbon black, Ketjen black, carbon dots, carbon nanotubes, graphene, and carbon nanofibers. The positive conductive agent in the positive conductive layer can improve the conductivity of the positive conductive layer, and thus improve the conductivity of the positive electrode tab and reduce the heat generation of the single battery cell.

[0663] Optionally, the mass content of the positive electrode binder in the positive electrode conductive layer is 50% to 70%. Illustratively, the mass content of the positive electrode binder is 50%, 60%, 65%, 70%, or a range composed of any two of the above values.

[0664] Illustratively, the positive electrode binder comprises one or more of polyvinylidene fluoride, polytetrafluoroethylene, a vinylidene fluoride-tetrafluoroethylene-propylene terpolymer, a vinylidene fluoride-hexafluoropropylene-tetrafluoroethylene terpolymer, a tetrafluoroethylene-hexafluoropropylene copolymer, a polyacrylic acid, and a fluorine-containing acrylic ester resin. The positive electrode binder in the positive electrode conductive layer can improve the adhesion between the positive electrode current collector and the positive electrode film layer, and improve the structural stability of the positive electrode sheet.

[0665] [Separator film]

[0666] In some embodiments, the separator film comprises a base film with a porous structure, and the porosity of the base film is 20% to 70%, optionally 35% to 60%. Illustratively, the porosity of the base film is 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, or a range composed of any two of the above values.

[0667] When the porosity of the base film in the embodiments of the present application is within the above range, the migration ability of lithium ions in the separator film can be improved, and the internal resistance of the single battery cell can be further reduced, thereby reducing heat generation.

[0668] In the embodiments of the present application, the porosity refers to the percentage of the volume of the pores in the separator film to the total volume of the separator film. The porosity can be tested according to the standard GB / T36363-2018 “Polyolefin separator for single battery cell”. It should be noted that the actual testing process can be slightly different from the standard in order to eliminate the influence on the testing of the porosity as much as possible, so as to obtain more accurate test values.

[0669] In some embodiments, the thickness of the base film can be, but is not limited to, 6 μm to 12 μm, optionally 6 μm to 9 μm. Illustratively, the thickness of the base film is 6 μm, 6.5 μm, 7 μm, 7.5 μm, 8 μm, 8.5 μm, 9 μm, 9.5 μm, 10 μm, 10.5 μm, 11 μm, 11.5 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 20.5 μm, or a range composed of any two of the above values.

[0670] Optionally, the material of the base film can be polypropylene.

[0671] When the thickness of the base film is in the above range, the migration path of lithium ions in the base film is shorter, and the internal resistance of the single battery can be further reduced, thereby reducing the heat generation.

[0672] In the embodiments of the present application, the separator film can be a base film, and the separator film optionally further comprises a functional layer disposed on at least one side of the base film, and the functional layer can comprise inorganic particles to improve the heat resistance of the separator film. Optionally, the functional layer is disposed on both sides of the base film.

[0673] In some embodiments, the functional layer comprises a first functional layer and a second functional layer, the first functional layer is disposed on one side of the base film, the first functional layer comprises first inorganic particles, the second functional layer is disposed on the other side of the base film, and the second functional layer comprises composite particles, the composite particles comprise second inorganic particles and a plurality of non-fluoropolymer particles, the second inorganic particles are attached to the surface of the non-fluoropolymer particles and / or dispersed in the interior of the non-fluoropolymer particles.

[0674] The first functional layer and the second functional layer have good heat resistance, which can improve the heat resistance of the separator film.

[0675] Optionally, the first functional layer can comprise a binder, and the binder can comprise at least one of a fluorine-containing binder or a polyacrylic acid binder, for example, polyvinylidene fluoride.

[0676] Optionally, the first inorganic particles comprise one or more of silicon oxide, aluminum oxide, boehmite, barium sulfate, calcium oxide, titanium oxide, zinc oxide, magnesium oxide, zirconium oxide, and tin oxide. The above first inorganic particles can improve the heat resistance of the first functional layer.

[0677] In the embodiments of the present application, the thickness of the base film has the meaning known in the art, and can be detected by methods and devices known in the art. For example, a newly prepared separator film can be taken as a sample, or a single battery that has been fully discharged (discharged to the lower limit cutoff voltage so that the charged state of the battery is about 0% SOC) can be disassembled in reverse, the separator film is obtained from the single battery, and the separator film is dried as a sample. The separator film is cut by an ion beam cutting instrument to form a cross section, and then the thickness of the cross section of the separator film and each layer thereof is measured by a scanning electron microscope.

[0678] The non-fluoropolymer particles in the second functional layer refer to polymers that are non-fluorinated polymers. For example, the non-fluoropolymer particles comprise an acrylate copolymer, and the acrylate copolymer comprises an acrylate-acrylonitrile-acrylamide-acryl copolymer. The acrylate copolymer has excellent bonding performance, and has high bonding stability with the base film. The molar ratio of each monomer in the copolymer can be any ratio, for example, the molar ratio is 35%:30%:15%:20%, or 40%:20%:10%:30%, or 45%:15%:20%:20%, etc.

[0679] The second inorganic particles in the composite particles make it difficult for the non-fluoropolymer particles to adhere to each other due to high-temperature treatment in the granulation process, so that the composite particles have pores, which is beneficial to the transmission of lithium ions, improves the ion conductivity of the isolation film, and the second inorganic particles can also improve the compression modulus of the composite particles. In the charging and discharging process, the composite particles are less likely to deform, making the structure of the isolation film more stable, which can improve the kinetic performance of the single cell and improve the rapid charging performance. Optionally, compared with the first functional layer, the second functional layer is arranged close to the negative electrode plate. Due to the fact that the composite particles are less likely to deform, the isolation film is less likely to cause side effects such as extrusion to the negative electrode plate, so that the kinetic performance of the negative electrode plate is stable. Correspondingly, the first functional layer is arranged close to the positive electrode plate.

[0680] Optionally, the second inorganic particles include one or more of silicon oxide, aluminum oxide, boehmite, barium sulfate, calcium oxide, titanium oxide, zinc oxide, magnesium oxide, zirconium oxide, and tin oxide. Optionally, the second inorganic particles include silicon oxide. The above-mentioned second inorganic particles can improve the heat resistance of the second functional layer, and can form composite particles with non-fluoropolymers, further improving the cycle stability and kinetic performance of the isolation film, and improving the cycle performance and rapid charging performance of the single cell.

[0681] The average particle size of the second inorganic particles is 5 nm to 100 nm, optionally 10 nm to 100 nm, and optionally 5 nm to 20 nm. Illustratively, the average particle size of the second inorganic particles is 5 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, 50 nm, 55 nm, 60 nm, 65 nm, 70 nm, 75 nm, 80 nm, 85 nm, 90 nm, 95 nm, 100 nm, or a range composed of any two of the above values. When the average particle size of the second inorganic particles is in the above range, it is beneficial to improve the heat resistance and compression modulus of the composite particles.

[0682] In the embodiments of the present application, the average particle size of the second inorganic particles has the meaning known in the art and can be detected by using devices and methods known in the art. For example, after obtaining the isolation film, the isolation film is dried as a sample, the isolation film is cut off using an ion beam cutter to form a cross section, and then the particle size of the second inorganic particles in the isolation film is measured using a scanning electron microscope. The particle sizes of a plurality of, for example, 50, second inorganic particles are measured, and the average value thereof is calculated as the average particle size of the second inorganic particles.

[0683] In some embodiments, the ion conductivity of the separation membrane is 0.3 mS / cm to 0.6 mS / cm. Exemplarily, the ion conductivity of the separation membrane is 0.3 mS / cm, 0.35 mS / cm, 0.4 mS / cm, 0.45 mS / cm, 0.5 mS / cm, 0.55 mS / cm, 0.6 mS / cm, or a range defined by any two of the above values.

[0684] When the ion conductivity of the separation membrane is in the above range, the migration ability of the separation membrane to lithium ions can be further improved, and the rapid charging performance of the single battery cell can be improved.

[0685] In the embodiments of the present application, the ion conductivity of the separation membrane is the meaning known in the art, which can be detected by using the devices and methods known in the art, for example,

[0686] Preparation of 2025 type button cell for testing: in a vacuum glove box, lithium sheet was put into the negative electrode shell, 150 μL of electrolyte was added, the electrolyte was a solution of 1 mol / L LiPF6 in EC / EMC / DEC = 3 / 5 / 2 (mass ratio), and then the separation membrane (area of 3.14 cm 2 , thickness of 12 μm) was put to make it close to the lithium sheet, 25 μL of electrolyte was added, and finally the positive electrode sheet (the positive electrode sheet can be the positive electrode sheet in Example 1) was placed thereon, and then it was packaged. The assembled button cell was taken out of the vacuum glove box and placed for 24 h for the next step of testing.

[0687] Test: in an electrochemical workstation, the test was carried out in the frequency range of 10 -1 ~ 10 6 Hz, the resistance Rb of the separation membrane was obtained, and the ion conductivity σ (unit: mS / cm) was calculated by the following formula,

[0688] σ = L / (R b × S)

[0689] Wherein: R b is the resistance of the separation membrane, and L and S are the thickness and area of the separation membrane to be tested, respectively.

[0690] In some embodiments, the base film comprises at least one of glass fiber, non-woven fabric, and polyolefin. The base film can be a single-layer film or a multi-layer composite film, and is not particularly limited. When the base film is a multi-layer composite film, the materials of the layers can be the same or different, and are not particularly limited.

[0691] Optionally, the polyolefin comprises at least one of polyethylene, polypropylene, and polyvinylidene fluoride.

[0692] In some embodiments, the positive electrode tab, the separator film, and the negative electrode tab can be made into an electrode assembly through a winding process and / or a stacking process.

[0693] Figure 23 and Figure 24 A structural schematic diagram of a single battery cell is shown.

[0694] In some embodiments, the single battery cell 7 can include a shell 20.

[0695] In some embodiments, the shell 20 of the single battery cell 7 can be a hard shell, such as a hard plastic shell, an aluminum shell, a steel shell, and the like. The shell 20 of the single battery cell 7 can also be a soft package, such as a pouch soft package. The material of the soft package can be plastic, such as at least one of polypropylene (PP), polybutylene terephthalate (PBT), and polybutylene succinate (PBS).

[0696] The shell 20 is a hollow structure, which can be used to package the electrode assembly 10 and the electrolyte described above.

[0697] The preparation method of the single battery cell 7 of the embodiments of the present application is known. In some embodiments, the positive electrode tab, the separator film, the negative electrode tab, and the electrolyte can be assembled to form the single battery cell 7. As an example, the positive electrode tab, the separator film, the negative electrode tab can be formed into the electrode assembly 10 through a winding process and / or a stacking process, the electrode assembly 10 is placed in the shell 20, the electrolyte is injected after drying, and the single battery cell 7 is obtained through processes such as vacuum packaging, standing, formation, shaping, and the like.

[0698] In some embodiments, the shell 20 includes a shell body 21 and an end cover 22, the shell body 21 has an opening, and the end cover 22 covers the opening.

[0699] The shape of the shell body 21 can be determined according to the specific shape of the electrode assembly 10. For example, if the electrode assembly 10 is a cylindrical structure, a cylindrical shell body can be selected, and if the electrode assembly 10 is a cuboid structure, a cuboid shell body can be selected. Alternatively, the electrode assembly 10 and the shell body 21 are both cuboid structures.

[0700] In some embodiments, the material of the shell body 21 includes steel, which has high mechanical strength and is not easy to deform, and can improve the use reliability and cycle performance of the single battery cell. Alternatively, the mass ratio of steel in the shell body 21 is the highest.

[0701] Optionally, the thickness of the shell 21 is 0.1mm to 0.5mm, optionally 0.2mm to 0.35mm. Illustratively, the thickness of the shell 21 is 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm or a range between any two of the above values. When the thickness of the shell 21 is within the above range, the mechanical strength of the shell 21 is high, which can improve the use reliability and cycle performance of the single battery cell 7, and the shell 21 occupies less space, and the internal space of the shell 21 is larger, which is beneficial to improve the energy density of the single battery cell 7.

[0702] From the appearance of the electrode assembly 10, the electrode assembly 10 includes a main body part 12, a first tab 11 and a second tab 13, the first tab 11 and the second tab 13 protrude from the main body part 12. The first tab 11 is a part of the first tab that is not coated with an active material layer, and the second tab 13 is a part of the second tab that is not coated with an active material layer. The first tab 11 and the second tab 13 are used to lead out the current in the main body part 12. The polarity of the first tab and the second tab is opposite, that is, one of the first tab and the second tab is a positive electrode tab, and the other of the first tab and the second tab is a negative electrode tab. Of course, the first tab 11 can be a positive electrode tab, and the second tab 13 can be a negative electrode tab.

[0703] Taking the first tab 11 as a negative electrode tab and the second tab 13 as a positive electrode tab as an example, the part of the negative electrode current collector in the negative electrode tab that is not coated with an active material layer is the negative electrode tab, and the active material coated on the negative electrode current collector in the negative electrode tab constitutes a negative electrode film layer, and the negative electrode film layer and the negative electrode current collector coated with the active material are part of the main body part 12. The part of the positive electrode current collector in the positive electrode tab that is not coated with an active material layer is the positive electrode tab, and the active material coated on the positive electrode current collector in the positive electrode tab constitutes a positive electrode film layer, and the positive electrode film layer and the posi...

Claims

1. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; charging the electrical device based on the target charging parameters corresponding to the target charging mode; Obtaining a current state of charge value and / or a remaining energy state value of the energy storage device, and determining that the energy storage device supports charging the electric device according to a charging power corresponding to a first charging mode when the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, wherein the first charge threshold is 50% and the first remaining energy threshold is 50%; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; The charging mode corresponding to the minimum duration difference among all the duration differences is determined as the target charging mode.

2. The charging method according to claim 1, characterized in that: The input power of the energy storage device is less than 150 kilowatts; in the first charging mode, the output power of the energy storage device is greater than or equal to 300 kilowatts.

3. The charging method according to claim 1, characterized in that: The charging mode of the charging device further includes a second charging mode, wherein the charging power indicated by the second charging parameter in the second charging mode is less than or equal to 300 kilowatts; The charging method further includes: When the target charging mode is the first charging mode and the energy storage device cannot charge the electric device with the first charging parameter, determining a second charging parameter corresponding to the second charging mode; The electrical device is charged using the second charging parameter.

4. The charging method according to claim 3, characterized in that: The charging mode of the charging device further includes a third charging mode, wherein the charging power indicated by the third charging parameter in the third charging mode is less than the charging power indicated by the second charging parameter in the second charging mode; The charging method further includes: When the target charging mode is the second charging mode and the energy storage device cannot charge the electrical device with the second charging parameter, determining a third charging parameter corresponding to the third charging mode; The electric device is charged using the third charging parameter.

5. The charging method according to any one of claims 1 to 4, characterized in that: The target charging parameter also indicates a target charging mode; In a case where the target charging mode includes the first charging mode, charging the electric device based on the target charging parameter corresponding to the target charging mode includes: Providing the full charging power indicated by the target charging parameter to the electrical device through the energy storage device; In a case where the target charging mode includes the second charging mode, charging the electric device based on the target charging parameter corresponding to the target charging mode includes: The power grid provides the electrical device with a portion of the charging power indicated by the target charging parameter, and the energy storage device provides the electrical device with another portion of the charging power indicated by the target charging parameter; the portion of power includes part or all of the charging power that the power grid can provide.

6. The charging method according to claim 5, characterized in that: Before charging the electric device based on the target charging parameters corresponding to the target charging mode, the charging method further includes: Determine the estimated charging period; When the estimated charging time period is within a first time period of power supply from the power grid, determining the target charging mode to be a first charging mode; When the estimated charging time period enters the second time period, determining the target charging mode to be the second charging mode; In a first sub-period of the estimated charging period, when the power grid is connected to a first time period, determining that the target charging mode in the first sub-period is the first charging mode; and in a second sub-period of the estimated charging period, when the power grid is connected to a second time period, determining that the target charging mode in the second sub-period is the second charging mode; The first time period and the second time period are different.

7. The charging method according to any one of claims 1 to 4, characterized in that: The energy storage device and / or charging device meets one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

8. The charging method according to claim 7, characterized in that: The ratio between the rated energy of the energy storage device and the rated power of the energy storage device is less than or equal to 1:

4.

9. The charging method according to claim 4, characterized in that: The charging method further includes: Determining, based on the state of charge value and / or the remaining energy state value, whether the energy storage device can charge the electrical device with the target charging parameter; When it is determined that the energy storage device can charge the electric device with the target charging parameter, the electric device is charged based on the target charging parameter.

10. The charging method according to claim 9, characterized in that: Determining whether the energy storage device can charge the electrical device with the target charging parameter based on the state of charge value and / or the remaining energy state value includes: When the state of charge value is less than the first charge threshold and greater than or equal to the second charge threshold, and / or the remaining energy state value is less than the first remaining energy threshold and greater than or equal to the second remaining energy threshold, it is determined that the energy storage device supports charging the electrical device according to the charging power corresponding to the second charging mode.

11. The charging method according to claim 10, characterized in that: The charging method further includes: When the state of charge value is less than the first charge threshold and / or the remaining energy state value is less than the first remaining energy threshold, outputting a first prompt message, wherein the first prompt message is used to indicate that the charging device currently does not support the first charging mode and needs to switch to the second charging mode or the third charging mode; When the state of charge value is less than the second charge threshold and / or the remaining energy state value is less than the second remaining energy threshold, outputting a second prompt message, wherein the second prompt message indicates that the charging device currently does not support the second charging mode and needs to switch to the third charging mode; In response to a charging mode selected based on the first prompt message or the second prompt message, the selected charging mode is determined as a target charging mode.

12. The charging method according to any one of claims 1 to 4, characterized in that: In response to a charging event, determining charging requirement information of the powered device includes: In response to a charging event, receiving a charging request message sent by a charging gun or a user end, wherein the charging request message includes attribute information of a battery of the power-consuming device; the attribute information of the battery includes at least: a plurality of charging parameters applicable to the power-consuming device; Based on the attribute information of the battery, charging requirement information of the electric device is determined.

13. The charging method according to claim 12, characterized in that: Determining charging requirement information of the power-consuming device based on the attribute information of the battery includes: Based on the attribute information and charging strategy of the battery, charging requirement information of the electric device is determined; wherein the charging strategy is set for the electric device or the charging apparatus.

14. The charging method according to claim 12, characterized in that: Determining charging requirement information of the power-consuming device based on the attribute information of the battery includes: Based on the attribute information of the battery, determining and outputting estimated consumption parameter values ​​corresponding to the multiple charging modes respectively, the estimated consumption parameters including estimated charging time and / or estimated charging cost; In response to a selection operation of a plurality of estimated consumption parameter values, the selected estimated consumption parameter value is determined as the charging demand information of the electric device.

15. A charging method, characterized in that: The charging method includes: In response to a charging event, determining, based on charging demand information of the electric device, an estimated charging period for the electric device and a target charging mode for charging the electric device by a charging device, the charging device including an energy storage device; determining a target charging mode for charging the electrical device during the estimated charging period; Based on the target charging mode, charging the electrical device with target charging parameters corresponding to the target charging mode; Obtaining a current state of charge value and / or a remaining energy state value of the energy storage device, and determining that the energy storage device supports charging the electric device according to a charging power corresponding to a first charging mode when the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, wherein the first charge threshold is 50% and the first remaining energy threshold is 50%; determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; The charging mode corresponding to the minimum duration difference among all the duration differences is determined as the target charging mode.

16. The charging method according to claim 15, characterized in that: The charging method further includes: When it is determined that charging is completed, a charging fee for the electric device is determined based on an actual charging period of the electric device and an electricity price during the actual charging period.

17. The charging method according to claim 15, characterized in that: Based on the target charging mode, charging the electrical device with target charging parameters corresponding to the target charging mode includes: When the target charging mode includes the first charging mode, providing the electrical device with the full charging power indicated by the target charging parameter through the energy storage device in the charging device; When the target charging mode includes the second charging mode, a portion of the charging power indicated by the target charging parameter is provided to the electric device through the power grid, and another portion of the charging power indicated by the target charging parameter is provided to the electric device through the energy storage device; the portion of power includes part or all of the charging power that the power grid can provide.

18. The charging method according to any one of claims 15 to 17, characterized in that: The determining of a target charging mode for charging the electrical device during the estimated charging period includes: When the estimated charging time period is within a first time period of power supply from the power grid, determining the target charging mode to be a first charging mode; When the estimated charging time period enters the second time period, determining the target charging mode to be the second charging mode; In a first sub-period of the estimated charging period during which power is supplied from the grid, determining that the target charging mode is the first charging mode during the first sub-period; and in a second sub-period of the estimated charging period during which power is supplied from the grid, determining that the target charging mode is the second charging mode during the second sub-period; The first time period and the second time period are different.

19. The charging method according to claim 17, characterized in that: The charging method includes: When the current time falls within the first time period, determining whether there is a charging event for the electric device; estimating energy consumption of the energy storage device based on the charging event; Based on the current state of charge value and / or remaining energy state value of the energy storage device and the energy consumption of the energy storage device, it is determined whether the energy storage device transmits electric energy to the power grid.

20. The charging method according to claim 17, characterized in that: The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

21. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; In response to the selection of the charging mode, obtaining a current state of charge value and / or a remaining energy state value of the energy storage device in the charging device; Based on the state of charge value and / or the remaining energy state value, determining whether the energy storage device can charge the electrical device with target charging parameters corresponding to a target charging mode; the target charging mode is a charging mode in which the charging device charges the electrical device, and when the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, determining that the energy storage device supports charging the electrical device with a charging power corresponding to the first charging mode, the first charge threshold being 50%, and the first remaining energy threshold being 50%; If it is determined that the energy storage device can charge the electrical device with the target charging parameter, charging the electrical device based on the target charging parameter; The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:4; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; at least one charging mode of the charging device including the first charging mode; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; The charging mode corresponding to the minimum duration difference among all the duration differences is determined as the target charging mode.

22. The charging method according to claim 21, characterized in that: When the selected charging mode is the first charging mode, the charging power indicated by the first charging parameter in the first charging mode is greater than 300 kilowatts.

23. The charging method according to claim 22, characterized in that: Determining, based on the state of charge value and / or the remaining energy state value, whether the energy storage device can charge the electrical device with target charging parameters corresponding to a target charging mode includes: When the state of charge value is greater than or equal to a first charge threshold, and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, determining that the energy storage device supports charging the electric device according to the charging power corresponding to the first charging mode; When the state of charge value is less than the first charge threshold and greater than or equal to the second charge threshold, and / or the remaining energy state value is less than the first remaining energy threshold and greater than or equal to the second remaining energy threshold, it is determined that the energy storage device supports charging the electrical device according to the charging power corresponding to the second charging mode.

24. The charging method according to claim 23, characterized in that: The charging method further includes: When the state of charge value is less than the first charge threshold and / or the remaining energy state value is less than the first remaining energy threshold, outputting a first prompt message, wherein the first prompt message is used to indicate that the charging device currently does not support the first charging mode and needs to switch to the second charging mode or the third charging mode; When the state of charge value is less than the second charge threshold and / or the remaining energy state value is less than the second remaining energy threshold, outputting a second prompt message, wherein the second prompt message indicates that the charging device currently does not support the second charging mode and needs to switch to the third charging mode; A selected charging mode is acquired based on the first prompt message or the second prompt message.

25. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; In response to selection of the first charging mode, obtaining a current state of charge value and / or a residual energy state value of the energy storage device in the charging device; When the state of charge value is greater than or equal to a first charge threshold, and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, determining that the energy storage device supports charging the electric device according to the charging power corresponding to the first charging mode, the first charge threshold is 50%, and the first remaining energy threshold is 50%; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes the first charging mode, and the charging power indicated by the first charging parameter in the first charging mode is greater than 300 kilowatts; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; The charging mode corresponding to the minimum duration difference among all the duration differences is determined as the target charging mode.

26. The charging method according to claim 25, characterized in that: The charging method includes: When the state of charge value is less than the first charge threshold and / or the remaining energy state value is less than the first remaining energy threshold, outputting a first prompt message, wherein the first prompt message is used to indicate that the charging device currently does not support the first charging mode and needs to switch to the second charging mode or the third charging mode; It is characterized in that the charging power indicated by the second charging parameter in the second charging mode is less than or equal to 300 kilowatts; the charging power indicated by the third charging parameter in the third charging mode is less than the charging power indicated by the second charging parameter in the second charging mode.

27. The charging method according to claim 25 or 26, characterized in that: The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

28. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes a first charging mode; Obtaining a current state of charge value and / or a remaining energy state value of the energy storage device, and determining that the energy storage device supports charging the electric device according to the charging power corresponding to the first charging mode when the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, where the first charge threshold is 50% and the first remaining energy threshold is 50%; In response to selection of the second charging mode, obtaining a current state of charge value and / or a residual energy state value of the energy storage device in the charging device; When the state of charge value is less than the first charge threshold and greater than or equal to the second charge threshold, and / or the remaining energy state value is less than the first remaining energy threshold and greater than or equal to the second remaining energy threshold, determining that the energy storage device supports charging the electric device according to the charging power corresponding to the second charging mode; Wherein, the charging power indicated by the second charging parameter in the second charging mode is less than or equal to 300 kilowatts; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; The charging mode corresponding to the minimum duration difference among all the duration differences is determined as the target charging mode.

29. The charging method according to claim 28, characterized in that: The charging method includes: When the state of charge value is less than the second charge threshold, and / or the remaining energy state value is less than the second remaining energy threshold, a second prompt message is output, wherein the second prompt message indicates that the charging device currently does not support the second charging mode and needs to switch to the third charging mode; wherein the charging power indicated by the third charging parameter in the third charging mode is less than the charging power indicated by the second charging parameter in the second charging mode.

30. The charging method according to claim 28, characterized in that: The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

31. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes a first charging mode; In response to the selection of the charging mode, obtaining a current state of charge value and / or a remaining energy state value of an energy storage device in the charging device; wherein, if a charging power indicated by a first charging parameter in the first charging mode is greater than 300 kilowatts, and if the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, determining that the energy storage device supports charging the electrical device according to the charging power corresponding to the first charging mode, the first charge threshold is 50%, and the first remaining energy threshold is 50%; When the state of charge value is greater than a third charge threshold, and / or the remaining energy state value is greater than a third remaining energy threshold, providing the electrical device with the full charging power indicated by the charging parameters in the charging mode through the energy storage device; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; Determine the charging mode corresponding to the minimum duration difference among all the duration differences as the target charging mode; The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

32. The charging method according to claim 31, characterized in that: The input power of the energy storage device is less than 150 kilowatts; in the first charging mode, the output power of the energy storage device is greater than or equal to 300 kilowatts.

33. The charging method according to claim 31 or 32, characterized in that: The charging method further includes: When the state of charge value is less than the third charge threshold and greater than or equal to the fourth charge threshold, and / or the remaining energy state value is less than the third remaining energy threshold and greater than or equal to the fourth remaining energy threshold, the energy storage device provides part of the charging power indicated by the charging parameters to the electrical device.

34. The charging method according to claim 31 or 32, characterized in that: The charging method includes: When the state of charge value is greater than or equal to a fifth charge threshold, and / or the residual energy state value is greater than or equal to a fifth residual energy threshold, transmitting electric energy to a power grid through the energy storage device; When the state of charge value is less than a sixth charge threshold, and / or the remaining energy state value is less than a sixth remaining energy threshold, the energy storage device is charged through the power grid.

35. A charging method, characterized in that: The charging method includes: In response to the charging event, determining charging demand information of the powered device; Based on the charging demand information, determining a target charging mode for a charging device to charge the electrical device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; The determining, based on the charging demand information, a target charging mode for charging the electrical device by a charging device includes: determining, based on the charging demand information, a target charging parameter for charging the electrical device by the charging device from at least one charging mode of the charging device; The at least one charging mode of the charging device includes a first charging mode; In response to a charging event, sending a state parameter of an energy storage device in the charging device to a charging control device of the charging device; the state parameter includes one or more of the following: a state of charge value and a remaining energy state value; receiving a discharge parameter of the energy storage device sent by the charging control device, wherein the discharge parameter of the energy storage device is determined based on a target charging mode for charging the electrical device and the state parameter; When the circuit between the energy storage device and the bidirectional DC / DC module of the charging device is conductive, controlling the energy storage device to discharge according to the discharge parameters; Obtaining a current state of charge value and / or a remaining energy state value of the energy storage device, and determining that the energy storage device supports charging the electric device according to a charging power corresponding to a first charging mode when the state of charge value is greater than or equal to a first charge threshold and / or the remaining energy state value is greater than or equal to a first remaining energy threshold, wherein the first charge threshold is 50% and the first remaining energy threshold is 50%; The charging demand information includes expected charging time; Determining, based on the charging demand information and from at least one charging mode of the charging device, a target charging parameter for charging the electrical device by the charging device, includes: Determining an estimated charging time corresponding to at least one charging mode of the charging device; Determining a difference between the expected charging time and the estimated charging time for each charging mode; Determine the charging mode corresponding to the minimum duration difference among all the duration differences as the target charging mode; Wherein, when the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a discharge parameter of the energy storage device, and the discharge parameter of the energy storage device indicates a discharge power greater than 300 kilowatts.

36. The charging method according to claim 35, characterized in that: When the target charging mode is the second charging mode, the charging power indicated by the discharge parameter of the energy storage device in the second charging mode is less than or equal to 300 kilowatts.

37. The charging method according to claim 35 or 36, characterized in that: The energy storage device and / or the charging device meet one or more of the following conditions: The ratio between the rated energy of the energy storage device and the maximum discharge power of the energy storage device is not greater than 1:3; The energy density of the energy storage device is greater than or equal to 380 watt-hours / liter; The ratio between the rated energy of the energy storage device and the maximum charging power of the charging device is less than 1:

4.

38. A charging control device, configured to execute the steps of the charging method according to any one of claims 1 to 37, characterized in that: The charging control device includes: A first determining module is configured to determine charging requirement information of the electric device in response to a charging event; A second determining module is configured to determine a target charging mode for a charging device to charge the electrical device based on the charging demand information, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; a first charging module configured to charge the electrical device based on a target charging parameter corresponding to the target charging mode; Wherein, when the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts.

39. A charging system comprising a charging device and an electrical device, wherein the charging device is configured to perform the steps of the charging method according to any one of claims 1 to 37, characterized in that: The charging device includes an energy storage device; The charging device is configured to determine, in response to a charging event, charging demand information of an electric device; determine, based on the charging demand information, a target charging mode for charging the electric device by the charging device, wherein the target charging mode corresponds to a target charging parameter; the charging device includes an energy storage device; and charge the electric device based on the target charging parameter corresponding to the target charging mode; Wherein, when the target charging mode includes the first charging mode, the target charging parameter corresponding to the first charging mode includes a first charging parameter, and the charging power indicated by the first charging parameter is greater than 300 kilowatts.

40. A charging device, characterized in that: including a charge and discharge circuit and a charge control device; The charging control device is configured to implement the steps of the charging method according to any one of claims 1 to 37 when executing a program.

41. The charging device according to claim 40, characterized in that The charging device includes An energy storage module, the energy storage module comprising one or more energy storage units, each of the energy storage units having a first positive power supply terminal and a first negative power supply terminal, the one or more energy storage units being connected to a second positive power supply terminal and a second negative power supply terminal of the energy storage module via the first positive power supply terminal and the first negative power supply terminal, the energy storage module being configured to provide a first direct current; a charging module connected to the second positive power supply terminal and the second negative power supply terminal of the energy storage module, the charging module being configured to provide charging output based on the first direct current, the maximum charging output power of the charging module being greater than or equal to 350 kilowatts, and / or the rated charging output power of the charging module being greater than or equal to 290 kilowatts.

42. The charging device according to claim 41, characterized in that Also includes: An input module is adapted to provide charging energy to each of the energy storage units.

43. The charging device according to claim 42, characterized in that The ratio of the maximum charging output power of the charging module to the maximum output power of the input module is greater than 1 and less than or equal to 15, and / or the ratio of the rated charging output power of the charging module to the rated output power of the input module is greater than 1 and less than or equal to 15.

44. The charging device according to claim 42, characterized in that Each of the energy storage units includes a battery subunit, and a ratio between the rated output power of the input module and the rated energy of the battery subunit is greater than or equal to 1 / n1, where the value range of n1 is 1-4.

45. The charging device according to claim 41, characterized in that Each of the energy storage units includes a battery subunit, and the ratio between the rated energy of the battery subunit and the rated charging output power of the charging module is greater than or equal to 1 / (n2*n3), where the value range of n2 is 94%~99%, and the value range of n3 is 4~6.

46. ​​The charging device according to claim 41, characterized in that Each of the energy storage units includes a battery subunit, the ratio between the rated energy of the battery subunit and the rated power of the battery subunit is less than or equal to 1 / 3, and / or the volume energy density of the battery subunit is greater than or equal to 380 watt-hours / liter.

47. The charging device according to claim 41, characterized in that The one or more energy storage units are connected in series and / or in parallel between the second positive power supply terminal and the second negative power supply terminal of the energy storage module through the first positive power supply terminal and the first negative power supply terminal to provide the first direct current.

48. The charging device according to any one of claims 41 to 47, characterized in that: Each of the energy storage units includes a battery subunit, the battery subunit includes a single cell, the single cell includes an electrolyte, the electrolyte includes an electrolyte salt, the electrolyte salt includes lithium hexafluorophosphate, and the concentration of the lithium hexafluorophosphate is in the range of 0.5 mol / L-1.0 mol / L.

49. The charging device according to claim 48, characterized in that The electrolyte further includes an organic solvent, and the organic solvent includes a carbonate solvent.

50. The charging device according to claim 48, characterized in that The electrolyte salt further includes a fluorine-containing sulfonyl imide salt, and the concentration of the fluorine-containing sulfonyl imide salt is in the range of 0.2 mol / L to 0.5 mol / L.

51. The charging device according to claim 48, characterized in that The electrolyte further includes an organic solvent, and the organic solvent includes a chain carboxylate solvent. Based on the total mass of the solvent, the mass content A of the chain carboxylate solvent satisfies: 5%≤A≤75%, Wherein, the chain carboxylate solvent includes a compound with the following structure: Wherein, R1 includes at least one of a hydrogen atom, a C1-C5 alkyl group or a C1-C5 haloalkyl group, and R2 includes a C1-C5 alkyl group and / or a C1-C5 haloalkyl group.

52. The charging device according to claim 51, characterized in that 40%≤A≤75%。 53. The charging device according to any one of claims 41 to 47, characterized in that: The energy storage device includes one or more energy storage units, each of the energy storage units includes a battery subunit, the battery subunit includes a single battery cell, the single battery cell includes a negative electrode plate, the negative electrode plate includes a negative electrode collector and a negative electrode film layer arranged on at least one side of the negative electrode collector, the negative electrode film layer includes a negative electrode active material, the negative electrode active material includes a carbon-based material, and the carbon-based material includes at least one of natural graphite and artificial graphite.

54. The charging device according to claim 53, characterized in that The volume average particle size Dv50 of the negative electrode film layer is in the range of 8.2μm-13.5μm; or, the negative electrode film layer includes a first negative electrode active material layer and a second negative electrode active material layer arranged in a stacked manner, the first negative electrode active material layer is located on the side close to the negative electrode current collector, the volume average particle size Dv50 of the negative electrode active material in the first negative electrode active material layer is 9.5μm-18.5μm, and the volume average particle size Dv50 of the negative electrode active material in the second negative electrode active material layer is 7.8μm-14.3μm.

55. The charging device according to any one of claims 41 to 47, characterized in that: Each of the energy storage units includes a battery subunit, the battery subunit includes a single battery cell, the single battery cell includes a negative electrode plate, the negative electrode plate includes a negative electrode current collector and a negative electrode film layer located at least on one side of the negative electrode current collector, and the negative electrode film layer includes a negative electrode active material; The compaction density of the negative electrode film layer of the single cell is 1.15g / cm 3 -1.36g / cm 3 , and / or, the single-sided coating weight of the negative electrode film layer is 0.09g / 1540.25mm 2 -0.17g / 1540.25mm 2 .

56. The charging device according to any one of claims 41 to 47, characterized in that Each of the energy storage units includes a battery subunit, the battery subunit includes a single battery cell, the single battery cell includes a positive electrode plate, the positive electrode plate includes a positive electrode current collector and a positive electrode film layer located at least on one side of the positive electrode current collector, and the positive electrode film layer includes a positive electrode active material; The compaction density of the positive electrode film layer of the single cell is 2.5g / cm when the cell is 100% charged. 3 -2.8g / cm 3 , and / or, the single-sided coating weight of the positive electrode film layer is 0.2g / 1540.25mm 2 -0.37g / 1540.25mm 2 .

57. The charging device according to any one of claims 41 to 47, characterized in that Each of the energy storage units includes a battery subunit, the battery subunit includes a single battery cell, the single battery cell includes a positive electrode plate, the positive electrode plate includes a positive electrode collector and a positive electrode film layer located at least on one side of the positive electrode collector, and the thickness of the positive electrode collector is 10μm-15μm.

58. The charging device according to any one of claims 41 to 47, characterized in that Each of the energy storage units includes a battery subunit, each of the battery subunits includes a single battery cell, each of the single battery cells includes an isolation membrane, and each isolation membrane includes a base membrane with a porous structure. The porosity of the base membrane is 20% to 70%.

59. The charging device according to any one of claims 41 to 47, characterized in that: Each of the energy storage units includes a battery subunit, the battery subunit includes a positive electrode plate, the positive electrode plate includes a positive electrode current collector and a positive electrode film layer provided on at least one side of the positive electrode current collector, the positive electrode film layer includes a positive electrode active material, and the positive electrode active material includes a lithium-containing phosphate; The lithium-containing phosphate includes phosphate particles and a coating layer, wherein the coating layer is coated on at least a portion of the surface of the phosphate particles, and the coating layer includes one or more elements selected from the group consisting of C, Fe, Ti, Zr, Hf, Ge, and Sn.

60. The charging device according to claim 59, characterized in that The coating layer includes a fast ion conductor, wherein the fast ion conductor includes a general formula of Li 3-d Fe 2-d M 2d (PO4)3 compound, M2 includes at least one element selected from Ti, Zr, Hf, Ge and Sn, 0≤d≤1.

61. The charging device according to any one of claims 41 to 47, characterized in that: Each of the energy storage units includes a battery subunit, each of the battery subunits includes a positive electrode plate, each of the positive electrode plates includes a positive electrode current collector, a positive electrode conductive layer and a positive electrode film layer, the positive electrode film layer is provided on at least one side of the positive electrode current collector, the positive electrode conductive layer is located between the positive electrode current collector and the positive electrode film layer, and the thickness of the positive electrode conductive layer is in the range of 0.5 μm-2 μm; and / or Each of the energy storage units includes a battery subunit, which includes a negative electrode plate. The negative electrode plate includes a negative electrode current collector, a negative electrode conductive layer and a negative electrode film layer. The negative electrode film layer is arranged on at least one side of the negative electrode current collector, and the negative electrode conductive layer is located between the negative electrode current collector and the negative electrode film layer. The thickness of the negative electrode conductive layer is in the range of 0.5μm-2μm.

62. The charging device according to claim 61, characterized in that The positive electrode conductive layer comprises a positive electrode conductive agent, and the mass content of the positive electrode conductive agent is in the range of 30%-50% based on the total mass of the positive electrode conductive layer; and / or The positive electrode conductive layer includes a positive electrode binder. Based on the total mass of the positive electrode conductive layer, the mass content of the positive electrode binder is in the range of 50%-70%.

63. The charging device according to claim 61, characterized in that The negative electrode conductive layer comprises a negative electrode conductive agent, and the mass content of the negative electrode conductive agent is in the range of 20%-40% based on the total mass of the negative electrode conductive layer; and / or The negative electrode conductive layer includes a negative electrode binder. Based on the total mass of the negative electrode conductive layer, the mass content of the negative electrode binder is in the range of 60% to 80%.

64. A computer-readable storage medium, characterized in that A computer program is stored thereon, which implements the steps of the charging method according to any one of claims 1 to 37 when executed by the charging control device.

65. A computer program product, characterized in that The method comprises a computer program or instructions, which, when executed by a charging control device, implements the steps of the charging method according to any one of claims 1 to 37.

Images