Method for battery equalization, battery management system, battery system and power consuming device

Abstract

The embodiment of the present application provides a battery equalization method, a battery management system, a battery system and a power utilization device, the method comprises the following steps: controlling a battery device to perform N+1th charging under a target charging condition; determining a voltage-charge amount corresponding relationship of a reference battery cell in a plurality of battery cells of the battery device according to the N+1th charging; determining a plurality of charge amounts corresponding to the voltage of the plurality of battery cells charged to any time point in the process of the N+1th charging according to the corresponding relationship; and equalizing the battery device according to the plurality of charge amounts. The battery equalization method, the battery management system, the battery system and the power utilization device provided by the embodiment of the present application can reasonably equalize the battery device, and improve the performance and service life of the battery device.

Description

Technical Field

[0001] This application relates to the field of battery technology, and more specifically, to a battery balancing method, a battery management system, a battery system, and an electrical device. Background Technology

[0002] Due to their advantages such as high energy density, rechargeability, safety and environmental friendliness, battery devices are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields.

[0003] To improve the performance and lifespan of battery devices, battery balancing is necessary. However, for battery devices with a charge-to-discharge ratio greater than 1 during a single charge-discharge cycle, the voltage-charge correspondence between individual battery cells varies significantly; that is, different cells have different capacities at the same voltage. Therefore, it is difficult to accurately determine the capacity of each individual battery cell using pre-calibrated voltage-charge correspondences in the laboratory, making it impossible to reasonably balance such battery devices. Summary of the Invention

[0004] This application provides a battery balancing method, a battery management system, a battery system, and an electrical device, which can reasonably balance the battery device and improve its performance and lifespan.

[0005] In a first aspect, a battery balancing method is provided, comprising: controlling a battery device to perform a (N+1)th charge under target charging conditions, wherein the difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value, the target charging conditions including a charging capacity range and further including at least one of charging current, charging rate, or charging temperature; determining, based on the process of the (N+1)th charge, a voltage-charged capacity correspondence of a reference battery cell among a plurality of battery cells in the battery device; determining, based on the voltage-charged capacity correspondence, a plurality of charged capacities corresponding to the voltage of the plurality of battery cells charged to any voltage at any time during the (N+1)th charge; and balancing the battery device based on the plurality of charged capacities.

[0006] In this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions of the Nth charging time and the charging conditions of the Nth charging time is less than or equal to a preset value. This makes the voltage-charge correspondence of multiple battery cells in the battery device closer. Then, by using the voltage-charge correspondence of the reference battery cell determined in the N+1th charging process, the multiple charges corresponding to the voltage of multiple battery cells at the same moment in the N+1th charging process can be determined. This can cleverly convert the multiple charges corresponding to multiple battery cells at the same moment into the multiple charges, thereby enabling reasonable balancing of the battery device based on the multiple charges, meeting the balancing requirements of the battery device, and improving the performance and service life of the battery device.

[0007] In one possible implementation, based on the voltage-charge capacity correspondence, multiple charges corresponding to the voltage of multiple battery cells at any time during the N+1th charging process are determined, including: based on the voltage-charge capacity correspondence, determining multiple charges corresponding to the voltage of multiple battery cells when the reference battery cell is charged to the target voltage, wherein when the reference battery cell is charged to the target voltage, at least some of the voltages of the multiple battery cells are within the voltage range corresponding to at least one non-plateau region of the battery cell.

[0008] In this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions of the Nth charging time and the target charging conditions is less than or equal to a preset value. This allows the battery device to be charged for the N+1th time based on the multiple charging capacities corresponding to the voltages of the multiple battery cells when the reference battery cell is charged to the target voltage. This ensures that at least some or all of the voltages of the multiple battery cells fall within the non-plateau region, thereby accurately determining at least some or all of the corresponding charging capacities in the voltage-charging capacity correspondence. This enables reasonable and accurate balancing of the battery device, meeting the balancing requirements of the battery device and improving its performance and lifespan.

[0009] In one possible implementation, the voltage-charged capacity correspondence of a reference battery cell among the multiple battery cells of the battery device is determined according to the N+1th charging process, including: determining the voltage-charged capacity correspondence according to the process of charging the reference battery cell to the target voltage, wherein the reference battery cell is the battery cell with the highest voltage among the multiple battery cells.

[0010] In this embodiment, the battery cell with the highest voltage is used as the reference battery cell. This ensures that when the reference battery cell is charged to the target voltage, the voltage of other battery cells is lower than the target voltage. This facilitates the determination of multiple charging capacities corresponding to the voltage of multiple battery cells at the same time based on the voltage-charged capacity correspondence determined during the (N+1)th charging process, so as to balance the battery device.

[0011] In one possible implementation, the target voltage is within the voltage range corresponding to the target non-plateau region, and the target non-plateau region is any one of at least one non-plateau region.

[0012] In this embodiment, by setting the target voltage within the voltage range of any one of the non-platform regions in at least one of the non-platform regions of the battery cell, it is easier to better control the voltage of more battery cells in the battery device to be within the voltage range of any one of the non-platform regions when the reference battery cell is charged to the target voltage. This allows for accurate determination of the charging capacity of multiple battery cells based on their voltages, thereby improving the balancing effect of the battery device.

[0013] In one possible implementation, the target voltage includes the upper voltage limit corresponding to the target non-plateau region, where the target non-plateau region is any one of at least one non-plateau region.

[0014] In this embodiment, by setting the target voltage at the upper limit of the voltage of any one of the non-platform regions in at least one of the non-platform regions of the battery cell, when the reference battery cell with the highest voltage is charged to the target voltage, since the voltage of other battery cells is lower than that of the reference battery cell, the voltage of more or all of the battery cells can fall within the voltage range of the arbitrary non-platform region. Thus, the charging capacity of the battery cell can be accurately determined based on the voltage of the battery cell in the voltage-charging capacity correspondence relationship, thereby improving the balancing effect of the battery device.

[0015] In one possible implementation, the target non-platform region includes the last non-platform region among at least one non-platform region, and the at least one non-platform region is a non-platform region during the N+1th charging process.

[0016] In this embodiment, the target non-platform region is the last non-platform region in the N+1th charging process, and the target voltage is within the voltage range corresponding to the target non-platform region. In this way, the multiple charging quantities corresponding to multiple battery cells near the end of the charging process can be used as the control and balancing quantities. The closer the charging quantity difference of multiple battery cells is to the end of the charging process, the closer it is to their actual quantity difference. Therefore, precise balancing can be performed based on the multiple charging quantity differences, which can improve the balancing effect of the battery device.

[0017] In one possible implementation, the voltage in the last non-plateau region gradually increases.

[0018] In this embodiment, the voltage of the last non-platform zone gradually increases, which can establish a one-to-one correspondence between the voltage and the charged capacity in the last non-platform zone. This allows for accurate determination of the charged capacity corresponding to more battery cells, thereby enabling precise balancing of the battery device and improving the balancing effect of the battery device.

[0019] In one possible implementation, the target non-platform region includes the target region of the last non-platform region of at least one non-platform region, the voltage in the target region is increasing, and the at least one non-platform region is the non-platform region in the process of the N+1th charging.

[0020] In this embodiment, the target non-platform region is defined as the area where the voltage increases in the last non-platform region during the (N+1)th charging process, and the target voltage is within the voltage range corresponding to the target non-platform region. In this way, the charging capacity corresponding to multiple battery cells near the end of charging can be used as the control and balancing capacity. The closer the multiple battery cells are to the end of charging, the closer their corresponding charging capacity in the voltage-charging capacity curve is to their actual capacity. Furthermore, a one-to-one correspondence exists between voltage and charging capacity within the target non-platform region, allowing for accurate determination of the charging capacity corresponding to more battery cells. This enables precise balancing of the battery device and improves its balancing effect.

[0021] In one possible implementation, controlling the battery device to perform the N+1th charge under target charging conditions includes: controlling the battery device to perform the N+1th charge under target charging conditions when the balanced charge of the battery device within a preset time is less than or equal to a preset balanced charge.

[0022] In this embodiment, when the equalization charge of the battery device within a preset time is less than or equal to the preset equalization charge, i.e., when the equalization charge of the battery device within the preset time is insufficient, the battery device can be controlled to perform the N+1th charge under the target charging conditions. Then, by using the correspondence between the voltage and charge of the reference battery cell determined during the N+1th charge, the multiple charges corresponding to the voltages of multiple battery cells during the N+1th charge can be accurately determined. This allows for reasonable and accurate balancing of the battery device based on the multiple charges corresponding to the multiple battery cells, thereby improving the performance and lifespan of the battery device.

[0023] In one possible implementation, before controlling the battery device to perform the N+1th charge under the target charging conditions when the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge, the method further includes: controlling the battery device to perform the Nth charge; and determining the target charging conditions based on the charging conditions of the Nth charge.

[0024] In this embodiment, the target charging conditions can be determined based on the charging conditions of the Nth charge of the battery device. This allows the battery device to be controlled to perform the N+1th charge under the target charging conditions when the balanced charge of the battery device within a preset time is less than or equal to the preset balanced charge. Furthermore, by using the correspondence between the voltage and charge of the reference battery cell determined during the N+1th charge, the multiple charges corresponding to the voltages of multiple battery cells during the N+1th charge can be accurately determined. This enables reasonable and accurate balancing of the battery device based on the charge of multiple battery cells, thereby improving the performance and lifespan of the battery device.

[0025] In one possible implementation, when the battery device's balanced charge level within a preset time is less than or equal to a preset balanced charge level, controlling the battery device to perform a (N+1)th charge under target charging conditions includes: controlling the battery device to perform an Nth charge when the battery device's balanced charge level within a preset time is less than or equal to a preset balanced charge level; determining target charging conditions based on the charging conditions of the Nth charge; and controlling the battery device to perform the (N+1)th charge under target charging conditions.

[0026] In this embodiment, when the battery's balanced charge within a preset time is less than or equal to the preset balanced charge, i.e., when the battery's balanced charge within the preset time is insufficient, the battery can be controlled to perform the Nth charging. Then, the target charging conditions are determined based on the charging conditions of the Nth charging. Finally, the battery is controlled to perform the N+1th charging under the target charging conditions. By using the correspondence between the voltage and charge of the reference battery cell determined during the N+1th charging, the multiple charges corresponding to the voltages of multiple battery cells during the N+1th charging can be accurately determined. This allows for reasonable and accurate balancing of the battery based on the charge of multiple battery cells, thereby improving the performance and lifespan of the battery.

[0027] On the other hand, memory charging can only be triggered when the battery device's equalization charge is insufficient within a preset time. That is, the charging conditions will be recorded during the Nth charging process to determine the target charging conditions, which can reduce the data overhead of battery device equalization.

[0028] In one possible implementation, the preset equalization charge is determined based on the difference in self-discharge rate of the battery device over a preset time period.

[0029] In this embodiment of the application, a preset equalization charge can be determined based on the difference in self-discharge rate of the battery device within a preset time, so as to accurately know the equalization requirement of the battery device, so as to equalize the battery device when the equalization charge of the battery device within the preset time cannot meet the equalization requirement.

[0030] In one possible implementation, the target charging condition further includes at least one of the following: charging time corresponding to the charging current within the charging capacity range, charging time corresponding to the charging rate, or charging time corresponding to the charging temperature.

[0031] In the embodiments of this application, the closer the charging conditions of the Nth charge and the N+1th charge are, the closer the ratio of the charging capacity to the discharging capacity in one charge-discharge cycle of the battery device is to 1. The side reaction consumption of each battery cell in the N+1th charge process is reduced or even eliminated. The amount of electricity charged into each cell is more or almost entirely converted into an increase in electricity, thereby making the voltage-electricity relationship of multiple battery cells more consistent. In this way, the multiple charging capacities corresponding to multiple battery cells can be determined based on the voltage-charged electricity correspondence, and the battery device can be reasonably balanced.

[0032] In one possible implementation, the battery device includes a sodium-ion battery device.

[0033] In this embodiment, the N+1th charge can be performed based on the charging conditions of the Nth charge, thereby making the voltage-capacity correspondence of multiple sodium-ion battery cells in the sodium-ion battery device closer. Then, by using the voltage-charged capacity correspondence of the reference sodium-ion battery cell determined during the N+1th charge, the multiple charges corresponding to the voltages of multiple sodium-ion battery cells during the N+1th charge can be accurately determined. This cleverly converts the capacity of multiple sodium-ion battery cells into corresponding charges, thereby enabling reasonable balancing of the sodium-ion battery device based on the charges of multiple sodium-ion battery cells to meet the balancing requirements of the sodium-ion battery device and improve its performance and service life.

[0034] In one possible implementation, the ratio of the charge capacity to the discharge capacity during a single charge-discharge cycle of the battery device is greater than 1.

[0035] In this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions of the Nth charge and the charging conditions of the Nth charge is less than or equal to a preset value. This allows the voltage-charge correspondence of multiple battery cells in a battery device where the ratio of charged capacity to discharged capacity is greater than 1 in one charge-discharge cycle to be closer. Furthermore, by using the voltage-charged capacity correspondence of the reference battery cell determined in the N+1th charge, the multiple charged capacities corresponding to the voltages of multiple battery cells in the N+1th charge can be accurately determined. This cleverly converts the charge of multiple battery cells where the ratio of charged capacity to discharged capacity is greater than 1 in one charge-discharge cycle into the corresponding charged capacity, thereby enabling the battery device where the ratio of charged capacity to discharged capacity is greater than 1 in one charge-discharge cycle to be balanced reasonably based on the charged capacity of multiple battery cells.

[0036] Secondly, a battery management system is provided, comprising: a control unit for controlling a battery device to perform a (N+1)th charge under target charging conditions, wherein the difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value, the target charging conditions including a charging capacity range and further including at least one of charging current, charging rate, or charging temperature; a determining unit for determining, based on the process of the (N+1)th charge, a voltage-charged capacity correspondence of a reference battery cell among a plurality of battery cells in the battery device; and based on the voltage-charged capacity correspondence, determining a plurality of charged capacities corresponding to the voltage of the plurality of battery cells at any time during the (N+1)th charge; and a control unit for balancing the battery device based on the plurality of charged capacities.

[0037] In one possible implementation, a determining unit is specifically used to determine multiple charges corresponding to the voltages of multiple battery cells when a reference battery cell is charged to a target voltage, based on the voltage-charge capacity correspondence. When the reference battery cell is charged to the target voltage, at least some of the voltages of the multiple battery cells are within the voltage range corresponding to the non-plateau region of the battery cell.

[0038] In one possible implementation, a determining unit is specifically used to determine the voltage-charge correspondence based on the process of charging a reference battery cell to a target voltage. The reference battery cell is the battery cell with the highest voltage among multiple battery cells.

[0039] In one possible implementation, the target voltage is within the voltage range corresponding to the target non-plateau region, and the target non-plateau region is any one of at least one non-plateau region.

[0040] In one possible implementation, the target voltage includes the upper voltage limit corresponding to the target non-plateau region, where the target non-plateau region is any one of at least one non-plateau region.

[0041] In one possible implementation, the target non-platform region includes the last non-platform region among at least one non-platform region, and the at least one non-platform region is a non-platform region during the N+1th charging process.

[0042] In one possible implementation, the voltage in the last non-plateau region gradually increases.

[0043] In one possible implementation, the target non-platform region includes the target region of the last non-platform region in at least one non-platform region, the voltage in the target region is increasing, and the at least one non-platform region is the non-platform region in the process of the N+1th charging.

[0044] In one possible implementation, the target non-plateau region includes the last non-plateau region where the voltage increases during the (N+1)th charging process.

[0045] In one possible implementation, the control unit is specifically configured to control the battery device to perform the N+1th charging under target charging conditions when the battery device's balanced charge within a preset time is less than or equal to a preset balanced charge.

[0046] In one possible implementation, the control unit is further configured to control the battery device to perform the Nth charge; the determining unit is further configured to determine the target charging conditions based on the charging conditions of the Nth charge.

[0047] In one possible implementation, the control unit is specifically configured to control the battery device to perform the Nth charge when the battery device's equalization charge within a preset time is less than or equal to the preset equalization charge, and to record the charging conditions of the Nth charge; the determining unit is specifically configured to determine the target charging conditions based on the charging conditions of the Nth charge; and the control unit is specifically configured to control the battery device to perform the N+1th charge under the target charging conditions.

[0048] In one possible implementation, the preset equalization charge is determined based on the difference in self-discharge rate of the battery device over a preset time period.

[0049] In one possible implementation, the target charging condition further includes at least one of the following: charging time corresponding to the charging current within the charging capacity range, charging time corresponding to the charging rate, or charging time corresponding to the charging temperature.

[0050] In one possible implementation, the battery device includes a sodium-ion battery device.

[0051] In one possible implementation, the ratio of the charge capacity to the discharge capacity during a single charge-discharge cycle of the battery device is greater than 1.

[0052] Thirdly, a battery management system is provided, the battery management system including a memory and a processor, the memory for storing instructions, and the processor for reading instructions and executing methods as described in the first aspect and any possible implementation thereof.

[0053] Fourthly, a battery system is provided, comprising: a battery device including a plurality of battery cells; and a battery management system as in any possible implementation of the second or third aspect.

[0054] Fifthly, a battery system is provided, comprising: a first energy region, wherein a first battery device is disposed in the first energy region, the first battery device comprising a plurality of first battery cells; a second energy region, wherein a second battery device is disposed in the second energy region, the second battery device comprising a plurality of second battery cells, the first energy region and the second energy region being independently disposed; and a battery management system, the battery management system being configured to control the first battery device and / or the second battery device to perform methods as described in the first aspect and any possible implementation thereof.

[0055] A sixth aspect provides an electrical device comprising: a load; and a battery system as in any possible implementation of the fourth or fifth aspect, the battery system being connected to the load for supplying power to the load.

[0056] A seventh aspect provides an electrical device comprising: a first load; a second load; and a battery system as in any possible implementation of the fourth or fifth aspect, the battery system being connected to the first load for providing a first direct current to the first load, and the battery system being connected to the second load for providing a second direct current to the second load, the voltage of the first direct current being greater than the voltage of the second direct current.

[0057] Eighthly, a chip is provided, comprising: a processor for calling and running a computer program from memory, causing a device on which the chip is mounted to perform the methods as described in the first aspect and any possible implementation thereof.

[0058] Ninth aspect, a computer program is provided that, when executed by a computer, causes the computer to implement the methods of the first aspect and any possible implementation thereof.

[0059] In a tenth aspect, a computer-readable storage medium is provided for storing a computer program that, when executed by a computer, causes the computer to implement the methods described in the first aspect and any possible implementation thereof.

[0060] Eleventhly, a computer program product is provided, including computer program instructions that, when executed by a computer, cause the computer to implement the methods as described in the first aspect and any possible implementation thereof. Attached Figure Description

[0061] Figure 1 This is a schematic diagram of a vehicle provided in an embodiment of this application.

[0062] Figure 2 This is a schematic flowchart of the battery balancing method provided in an embodiment of this application.

[0063] Figure 3 This is another schematic flowchart illustrating the battery balancing method provided in an embodiment of this application.

[0064] Figure 4 This is a schematic diagram illustrating the correspondence between the voltage and the charge capacity of a single battery cell provided in an embodiment of this application.

[0065] Figure 5 This is another schematic flowchart illustrating the battery balancing method provided in an embodiment of this application.

[0066] Figure 6 This is another schematic flowchart illustrating the battery balancing method provided in an embodiment of this application.

[0067] Figure 7 This is a schematic block diagram of the battery management system provided in the embodiments of this application.

[0068] Figure 8 This is another schematic block diagram of the battery management system provided in the embodiments of this application.

[0069] Figure 9 This is a schematic block diagram of the battery system provided in the embodiments of this application.

[0070] Figure 10 This is another schematic block diagram of the battery system provided in the embodiments of this application.

[0071] Figure 11 This is a schematic block diagram of the electrical device provided in the embodiments of this application.

[0072] Figure 12 This is another schematic block diagram of the electrical device provided in the embodiments of this application. Detailed Implementation

[0073] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The detailed description of the following embodiments and the accompanying drawings are used to illustrate the principles of this application by way of example, but should not be used to limit the scope of this application, that is, this application is not limited to the described embodiments.

[0074] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "a plurality of" means two or more, unless otherwise explicitly defined. The terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing description of the drawings of this application, are intended to cover non-exclusive inclusion.

[0075] The term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / " in this text generally indicates that the preceding and following related objects have an "or" relationship.

[0076] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0077] In this application, the terms "upper," "lower," "left," "right," "inner," and "outer," indicating orientation or positional relationships, are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. "Vertical" is not vertical in the strict sense, but within the allowable tolerance range. "Parallel" is not parallel in the strict sense, but within the allowable tolerance range.

[0078] The directional terms used in the following description refer to the directions shown in the figures and are not intended to limit the specific structure of this application. It should also be noted in the description of this application that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0079] Due to their advantages such as high energy density, rechargeability, safety and environmental friendliness, battery devices are widely used in new energy vehicles, consumer electronics, energy storage systems and other fields.

[0080] Due to differences in manufacturing processes, usage conditions, and natural aging, the characteristics of each individual cell in a battery device, such as capacity, internal resistance, and self-discharge rate, cannot be completely identical, affecting the performance and lifespan of the battery device. Furthermore, this inconsistency is amplified during charging and discharging, further impacting the battery device's performance and lifespan.

[0081] For battery devices where the ratio of charged capacity to discharged capacity is greater than 1 during a single charge-discharge cycle, the voltage-capacity correspondence between individual battery cells varies significantly; that is, different battery cells have different capacities at the same voltage. Therefore, it is difficult to accurately determine the capacity of each individual battery cell using pre-calibrated voltage-capacity correspondences in the laboratory, making it impossible to reasonably balance such battery devices.

[0082] One charge-discharge cycle can be performed by first charging from a fully discharged state to a fully charged state, and then discharging from a fully charged state to a fully discharged state; or it can be performed by first discharging from a fully charged state to a fully discharged state, and then charging from a fully discharged state to a fully charged state.

[0083] For example, a fully charged state can be the state corresponding to the charging cutoff condition, such as the charging cutoff voltage, and a fully discharged state can be the state corresponding to the discharging cutoff condition, such as the discharging cutoff voltage.

[0084] Especially for some battery devices such as sodium-ion battery devices, the self-discharge rate of individual battery cells is high and the self-discharge rate varies greatly, so there is a clear need for balancing.

[0085] If the aforementioned battery devices are not properly balanced, their performance and lifespan will be greatly affected.

[0086] Therefore, for battery devices where the ratio of charge capacity to discharge capacity during a single charge-discharge cycle is greater than 1, especially for battery devices with large differences in self-discharge rate, such as sodium-ion battery devices, reasonable balancing is one of the urgent problems to be solved.

[0087] In view of this, embodiments of this application provide a battery balancing method, a battery management system, a battery system, and a power-consuming device. The method includes: controlling the battery device to perform a (N+1)th charge under target charging conditions, wherein the difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value, the target charging conditions including a charging capacity range and further including at least one of charging current, charging rate, or charging temperature within the charging capacity range; determining the voltage-charged capacity correspondence of a reference battery cell among a plurality of battery cells in the battery device according to the (N+1)th charge process; determining multiple charges corresponding to the voltage of the plurality of battery cells at any time during the (N+1)th charge process according to the voltage-charged capacity correspondence; and balancing the battery device according to the multiple charges.

[0088] The battery balancing method, battery management system, battery system, and power-consuming device provided in this application embodiment can reasonably balance the battery device, thereby improving the performance and service life of the battery device.

[0089] The technical solutions described in the embodiments of this application are applicable to various devices that use battery devices, such as mobile phones, portable devices, laptops, electric vehicles, electric toys, power tools, electric vehicles, ships, and spacecraft, etc. For example, spacecraft include airplanes, rockets, space shuttles, and spacecraft.

[0090] It should be understood that the technical solutions described in the embodiments of this application are not limited to the devices described above, but can also be applied to all devices that use batteries. However, for the sake of brevity, the following embodiments are all illustrated using vehicles as an example.

[0091] Figure 1 This is a schematic diagram of a vehicle provided in an embodiment of this application.

[0092] Vehicle 1 can be a gasoline-powered vehicle, a natural gas-powered vehicle, or a new energy vehicle. New energy vehicles can be pure electric vehicles, hybrid electric vehicles, or range-extended electric vehicles, etc. The interior of vehicle 1 can house a motor 40, a controller 30, and a battery system 6000. The controller 30 can manage the power supply from the battery system 6000 to the motor 40. For example, the battery system 6000 can be located at the bottom, front, or rear of vehicle 1.

[0093] The battery system 6000 can be used to power the vehicle 1. In some embodiments, the battery system 6000 can serve as the operating power source for the vehicle 1's electrical system, for example, to meet the power requirements of the vehicle 1 during startup, navigation, and operation.

[0094] In some embodiments, the battery system 6000 can also serve as a driving power source for the vehicle 1, replacing or partially replacing fuel or natural gas to provide driving power for the vehicle 1.

[0095] To meet diverse power demands, the battery system 6000 can include multiple battery cells, which can be connected in series, parallel, or a combination of both. For example, multiple battery cells can first be connected in series, parallel, or a combination of both to form a battery module. These battery modules can then be connected in series, parallel, or a combination of both to form a battery device. In other words, multiple battery cells can directly form a battery device; or they can first be formed into battery modules, and then the battery modules can be combined into a battery device.

[0096] The battery system 6000 may also include a battery management system, which can be used to monitor the state parameters of the battery device, such as current, voltage, state of charge (SOC), and temperature, in order to control the charging and discharging of the battery device.

[0097] It should be understood that Figure 1 The components shown are just examples. In actual applications, the components may have different names, or they may be added or deleted as needed.

[0098] The following combination Figures 2 to 6 The battery balancing method provided in the embodiments of this application will be described by way of example.

[0099] Figure 2 This is a schematic flowchart of the battery balancing method provided in an embodiment of this application.

[0100] 210, Control the battery device to perform the N+1th charge under the target charging conditions.

[0101] The difference between the target charging condition and the charging condition of the battery device for the Nth charge is less than or equal to a preset value. The target charging condition includes a charging capacity range and also includes at least one of the charging current, charging rate, or charging temperature within the charging capacity range.

[0102] That is, in this embodiment, the difference between the charging capacity range of the (N+1)th charge and the charging capacity range of the Nth charge is less than or equal to a preset value, meaning that there is an overlap in the charging capacity range between the Nth and N+1th charges. For example, if the SOC range of the Nth charge is 30%~70%, then the SOC range of the N+1th charge can be 20%~80%, or the SOC range of the N+1th charge can be 20%~70%, or the SOC range of the N+1th charge can be 30%~80%, and so on.

[0103] As an example, the charging capacity range of the (N+1)th charge is within the charging capacity range of the Nth charge. For instance, if the SOC range of the Nth charge is 30% to 70%, then the SOC range of the (N+1)th charge can be 40% to 60%.

[0104] In this embodiment, within the overlapping charging capacity range, the difference between at least one of the charging current, charging rate, or charging temperature of the N+1th charge and the Nth charge is less than or equal to the corresponding preset value.

[0105] For example, constant current charging is performed within the overlapping charging capacity range. The charging current of the (N+1)th charge is the same as that of the Nth charge, or the charging current of the (N+1)th charge is slightly smaller than that of the Nth charge, or the charging current of the (N+1)th charge is slightly larger than that of the Nth charge.

[0106] For example, when constant current charging is performed within the overlapping charging capacity range, the charging rate of the (N+1)th charge is the same as that of the Nth charge, or the charging rate of the (N+1)th charge is slightly smaller than that of the Nth charge, or the charging rate of the (N+1)th charge is slightly larger than that of the Nth charge.

[0107] For example, when constant current charging is performed within the overlapping charging capacity range, the charging temperature of the (N+1)th charge is the same as that of the Nth charge, or the charging temperature of the (N+1)th charge is slightly lower than that of the Nth charge, or the charging temperature of the (N+1)th charge is slightly higher than that of the Nth charge.

[0108] Here, controlling the temperature difference between the two consecutive charging sessions to be less than or equal to a preset value is to keep the charging current of the two consecutive charging sessions within a certain range.

[0109] Generally speaking, the ratio of charge capacity to discharge capacity in a single charge-discharge cycle of a battery device, especially some battery devices such as sodium-ion batteries, is usually greater than 1. Furthermore, due to differences among the individual cells in a battery device, such as manufacturing variations, self-discharge rates, state of charge (SOC), and temperature differences, the dynamic inconsistency of side reaction consumption among the cells leads to different degrees of side reactions during charging. This results in varying amounts of charge increase per cell during charging, and consequently, differences in the voltage-charge relationship between the cells during charging. In other words, a charge-to-discharge capacity ratio greater than 1 in a single charge-discharge cycle introduces a state-dependent charge loss, and the degree of this charge loss varies among cells in different states.

[0110] If the battery device performs memory charging, that is, the difference between the charging conditions of two consecutive charging is controlled within a range less than or equal to a preset value, the ratio of the charging capacity to the discharging capacity in one charge-discharge cycle can be reduced to close to 1. The side reaction consumption in the battery device is reduced or there are almost no side reactions. More or almost all of the charged electricity in the battery device is converted into an increase in electricity, thereby making the voltage-electricity relationship of the multiple battery cells in the battery device more consistent.

[0111] 220. Based on the N+1th charging process, determine the voltage-charged capacity correspondence of the reference battery cell among the multiple battery cells of the battery device.

[0112] In this embodiment, during the process of the battery device being recharged under the target charging conditions determined by the previous charging conditions, the correspondence between the voltage and the charged capacity of the reference battery cell in the battery device is determined.

[0113] As an example, the voltage of a reference battery cell can be measured in real time. For instance, the voltage of a reference battery cell can be monitored using a voltage sampling module.

[0114] The voltage-charge capacity correspondence can include a graph showing the relationship between the voltage of a single battery cell and the charge capacity, such as a curve, a table, or other forms of correspondence.

[0115] As an example, the power consumption in the embodiments of this application may include capacity or SOC, etc.

[0116] As an example, the charge capacity of a reference battery cell can be determined based on the charging current and charging time. For instance, the charging current of the reference battery cell can be monitored in real time using a current sampling module, and then the charge capacity of the reference battery cell can be calculated based on the charging current and charging time. The voltage-charge capacity correspondence is determined based on the voltage and charge capacity of the reference battery cell at each moment during the charging process.

[0117] As an example, the reference battery cell can be any battery cell in the battery pack. For instance, it could be the battery cell with the lowest voltage, the battery cell with the medium voltage, or the battery cell with the highest voltage.

[0118] As an example, the correspondence between the voltage of the reference battery cell and the amount of charge can be determined throughout the entire process of the N+1th charge of the battery device, from the start of charging to the completion of charging.

[0119] As another example, the correspondence between the voltage of a reference battery cell and the amount of charge can be determined during the N+1th charging process of the battery device, from the start of charging to the completion of charging.

[0120] For example, the stage from the start of charging to the completion of charging during the (N+1)th charging of the battery device can be any time during the (N+1)th charging of the battery device; or it can be the stage from the start of charging to a first voltage during the (N+1)th charging of the battery device, where the first voltage is less than the voltage at which the battery device is fully charged; or it can be the stage from the reference battery cell to a second voltage, where the second voltage is less than the voltage at which the reference battery cell is fully charged.

[0121] In this embodiment, the battery device discharges between the Nth charge and the (N+1)th charge, such as discharging to a power-consuming device. For example, after the Nth charge is completed, the battery device discharges until the voltage is below a certain threshold, and then performs the (N+1)th charge.

[0122] 230. Based on the voltage-charged capacity correspondence, determine the multiple charged capacities corresponding to the voltage at any time during the N+1th charging process for multiple battery cells.

[0123] As an example, this arbitrary time could be the time when the battery device has finished charging.

[0124] As another example, this arbitrary time could be a point in time before the battery device has finished charging.

[0125] In this embodiment, multiple charging capacities corresponding to the voltage of multiple battery cells can be found based on the correspondence between the voltage and charging capacity of a reference battery cell.

[0126] For example, when a single battery cell is charged to that arbitrary time, multiple battery cells, such as the first battery cell, the second battery cell, and the third battery cell, are charged to voltages a, b, and c, respectively. The charging amounts q1, q2, and q3 corresponding to voltages a, b, and c can be determined based on the voltage-charge amount correspondence.

[0127] It should be understood that during the entire charging process, or at any stage of the entire charging process, the actual amount of electricity charged into multiple battery cells should be equal or approximately equal.

[0128] It should be understood that the multiple charging capacities corresponding to multiple battery cells determined in step 230 based on the voltage-charging capacity correspondence are not the actual charging capacities of multiple batteries (except for the reference battery cell), but rather the mapped capacities obtained based on their voltage in the voltage-charging capacity correspondence.

[0129] For a reference battery cell, at any given time t, the charge Q of the reference battery cell can be obtained by looking up the voltage-charged capacity relationship based on its voltage. 充j =Q当前j -Q 初始j Q 当前j Q represents the total charge of the reference battery cell at any given time t. 初始j This represents the charge level of a baseline battery cell at the initial moment of charging.

[0130] For any battery cell i other than the reference battery cell, at any time t, the voltage-charged capacity correspondence can be found based on its voltage to obtain the charged capacity Q of battery cell i. 充i =Q 当前i -Q 初始j Q 当前i Let Q be the total charge of battery cell i at any time t. 初始j This represents the charge level of a baseline battery cell at the initial moment of charging.

[0131] Therefore, for each battery cell in the battery device, at any time t, the determined charge amount can be considered as the difference between its current charge and the initial charge of the reference battery cell, based on the voltage-charge amount correspondence. Here, it's equivalent to converting the charge of each battery cell in the battery device into the difference between its charge and the initial charge of the reference battery cell. Therefore, the charge amount of each battery cell can be obtained by looking up the voltage-charge amount correspondence in a table.

[0132] 240, balance the battery device based on multiple charge levels.

[0133] As an example, the battery device can be balanced based on the difference in charge level between each individual battery cell and the battery cell with the lowest charge level. For instance, the balancing time for each battery cell can be calculated based on the difference in charge level between each individual battery cell and the battery cell with the lowest charge level, as well as the balancing current.

[0134] As an example, the battery device can be balanced based on the difference in charge capacity between each of the multiple battery cells and the battery cell with the largest charge capacity.

[0135] As an example, the battery device can be balanced based on the difference in charge level between multiple battery cells and a reference battery cell.

[0136] Therefore, in this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions and the Nth charging conditions is less than or equal to a preset value. This makes the voltage-charge correspondence of multiple battery cells in the battery device closer. Then, by using the voltage-charge correspondence of the reference battery cell determined in the N+1th charging process, the multiple charges corresponding to the voltage of multiple battery cells at the same moment in the N+1th charging process can be determined. This can cleverly convert the multiple charges of multiple battery cells at the same moment into the multiple charges, thereby enabling reasonable balancing of the battery device based on the multiple charges, meeting the balancing requirements of the battery device, and improving the performance and service life of the battery device.

[0137] Figure 3 This is a schematic flowchart of the battery balancing method provided in an embodiment of this application.

[0138] 310, Control the battery device to perform the N+1th charge under the target charging conditions.

[0139] The difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value. The target charging conditions include a charging capacity range and at least one of the following: charging current, charging rate, or charging temperature within the charging capacity range.

[0140] 320. Based on the N+1th charging process, determine the correspondence between the voltage and the charged capacity of the reference battery cell among the multiple battery cells of the battery device.

[0141] The contents of steps 310 and 320 can be found in the descriptions of steps 210 and 220, which will not be repeated here.

[0142] 330. Based on the voltage-charge capacity correspondence, determine the multiple charge capacities corresponding to the voltages of multiple battery cells when the reference battery cell is charged to the target voltage.

[0143] When a reference battery cell is charged to the target voltage, at least a portion of the voltages of the multiple battery cells are within the voltage range corresponding to at least one non-plateau region of the battery cell.

[0144] In this embodiment, the multiple voltages corresponding to multiple battery cells when the reference battery cell is charged to the target voltage can be determined first, and then the multiple charging capacities corresponding to the multiple voltages can be determined according to the voltage-charge capacity correspondence.

[0145] In some embodiments, certain battery devices exhibit a plateau region during charging. The plateau region of a battery cell refers to a phase where the voltage of the battery cell changes slowly or remains essentially constant over time, while the non-plateau region refers to a phase where the voltage of the battery cell changes relatively rapidly over time.

[0146] Figure 4 The illustration shows an example of the voltage-charged capacity relationship of a single battery cell provided in this application embodiment. In this example, the voltage-charged capacity relationship during the charging process can be divided into five stages: the first stage is the non-plateau region, where the voltage gradually increases and the charged capacity gradually increases as the charging process progresses; the second stage is the plateau region, where the voltage changes slowly or remains essentially unchanged as the charging process progresses, and the charged capacity gradually increases; the third stage is the non-plateau region, where the voltage gradually increases and the charged capacity gradually increases as the charging process progresses; the fourth stage is the plateau region, where the voltage changes slowly or remains essentially unchanged as the charging process progresses, and the charged capacity gradually increases; the fifth stage is the non-plateau region, where the voltage first increases, then decreases, and then increases again as the charging process progresses, and the charged capacity gradually increases.

[0147] For example, when the reference battery cell is charged to Figure 4 When the target voltage is shown, other battery cells, such as the other two battery cells, are charged to voltage a and voltage b respectively. The target voltage and the corresponding charging capacity can be determined based on the voltage-charged capacity correspondence.

[0148] It should be understood that Figure 4 The voltage-charged capacity relationship shown can be understood as the voltage-(real-time capacity - initial capacity of the reference battery cell) relationship.

[0149] In this embodiment, when the reference battery cell is charged to the target voltage, at least some or all of the voltages of the plurality of battery cells are within the voltage range corresponding to at least one non-plateau region.

[0150] As an example, when charging in the platform area, such as Figure 4 In the second and fourth stages shown, the voltage changes very little or remains essentially constant over time, while the charged capacity gradually increases. In this situation, the voltage-charged capacity correspondence shows that the same voltage corresponds to multiple charged capacities. If the voltages of multiple battery cells are all within the voltage range corresponding to this plateau region, it is difficult to accurately determine the charged capacity corresponding to each battery cell based on the voltage.

[0151] Charging in non-platform areas, such as Figure 4In the first and third stages shown, the voltage gradually increases over time, and the amount of charge also gradually increases. In this case, there is a one-to-one correspondence between voltage and charge, with one voltage corresponding to one amount of charge. If at least some or all of the voltages of multiple battery cells are within the voltage range corresponding to the non-plateau region, then the charge of at least some or all of the battery cells can be accurately obtained based on these voltages, thereby enabling the balancing of multiple battery cells.

[0152] As an example, the target voltage can be determined in advance through experimental testing.

[0153] For example, when a reference battery cell is charged to the target voltage, the voltages of multiple battery cells are all within the voltage range corresponding to at least one non-plateau region. Taking the reference battery cell as the one with the lowest voltage among multiple cells as an example, when the reference battery cell is charged to a certain voltage, the voltages of multiple battery cells are within the voltage range corresponding to the third stage of the non-plateau region as shown in Figure 4, and this certain voltage can be used as the target voltage; or, when the reference battery cell is charged to a certain voltage, the voltages of multiple battery cells are within the non-plateau region as shown in Figure 4, and the voltages of multiple battery cells are within the third stage of ... Figure 4 Within the voltage range corresponding to the second stage shown, when the reference battery cell continues to charge to the next voltage, some of the battery cells are in a plateau region, such as... Figure 4 Within the voltage range corresponding to the fourth stage shown, a certain voltage can be used as the target voltage.

[0154] In this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions of the Nth charging time and the target charging conditions is less than or equal to a preset value. This allows the battery device to be charged for the N+1th time based on the multiple charging capacities corresponding to the voltages of the multiple battery cells when the reference battery cell is charged to the target voltage. This ensures that at least some or all of the voltages of the multiple battery cells fall within the non-plateau region, thereby accurately determining at least some or all of the corresponding charging capacities in the voltage-charging capacity correspondence. This enables reasonable and accurate balancing of the battery device, meeting the balancing requirements of the battery device and improving its performance and lifespan.

[0155] 340, balances the battery device based on multiple charge levels.

[0156] The content of step 340 can be found in the relevant description in step 240, and will not be repeated here.

[0157] Figure 5 This is a schematic flowchart of the battery balancing method provided in an embodiment of this application.

[0158] 510, Control the battery device to perform the N+1th charge under the target charging conditions.

[0159] The difference between the target charging condition and the charging condition of the battery device for the Nth charge is less than or equal to a preset value. The target charging condition includes a charging capacity range and also includes at least one of the charging current, charging rate, or charging temperature within the charging capacity range.

[0160] 520. Based on the N+1th charging process, determine the voltage-charged capacity relationship when the reference battery cell is charged to the target voltage.

[0161] When the reference battery cell is charged to the target voltage, at least a portion of the voltages of the plurality of battery cells are within the voltage range corresponding to at least one non-plateau region of the battery cell.

[0162] The reference cell is the cell with the highest voltage among multiple cells.

[0163] The reference cell is the cell with the highest voltage among the multiple cells in the battery pack. When the reference cell is charged to the target voltage, the voltages of the other cells will necessarily be lower than the target voltage. Therefore, based on the voltage-charge correspondence obtained by charging the reference cell to the target voltage, it is possible to find the corresponding charge levels of the other cells at the same time, when the reference cell is charged to the target voltage.

[0164] In this embodiment, the battery cell with the highest voltage is used as the reference battery cell. This ensures that when the reference battery cell is charged to the target voltage, the voltage of other battery cells is lower than the target voltage. This facilitates the determination of multiple charging capacities corresponding to the voltage of multiple battery cells at the same time based on the voltage-charged capacity correspondence determined during the (N+1)th charging process, so as to balance the battery device.

[0165] 530. Based on the voltage-charge capacity correspondence, determine the multiple charge capacities corresponding to the voltages of multiple battery cells when the reference battery cell is charged to the target voltage.

[0166] When a reference battery cell is charged to the target voltage, at least some of the battery cells have voltages within the voltage range corresponding to the non-plateau region of the battery cell.

[0167] Taking the reference battery cell as the battery cell with the highest voltage among multiple cells as an example, when the reference battery cell is charged to the target voltage, the voltage of other battery cells is in the voltage range corresponding to the third stage in the non-platform region as shown in 4 and is less than the target voltage. At this time, there is a one-to-one correspondence between the voltage of multiple battery cells and the charging capacity. A charging capacity can be obtained through a voltage value.

[0168] For details regarding step 530, please refer to the relevant content of step 330; this application will not repeat them here.

[0169] 540, balances the battery device based on multiple charging capacities.

[0170] The content of step 540 can be found in the relevant content of step 240, and will not be repeated here.

[0171] In some embodiments, the target voltage is within the voltage range corresponding to the target non-platform region, and the target non-platform region is any one of at least one non-platform region.

[0172] That is, in this embodiment, the battery cell may include at least one non-platform region, such as Figure 4 The target voltage can be within the voltage range corresponding to any one of the three non-platform regions shown in the first, third, and fifth stages.

[0173] As an example, if the reference battery cell is the one with the lowest voltage among multiple battery cells, the target voltage can be within the voltage range corresponding to the target non-plateau region. For instance, the target voltage could be the lower limit voltage corresponding to the target non-plateau region or a voltage slightly higher than that lower limit voltage. Thus, when the reference battery cell is charged to the target voltage, at least some or all of the voltages of the multiple battery cells can be within the voltage range corresponding to the target non-plateau region.

[0174] As an example, in this embodiment, if the reference battery cell is the battery cell with the highest voltage among multiple battery cells, and the target voltage is within the voltage range corresponding to the target non-platform region, such as the target voltage being slightly lower than the upper limit voltage corresponding to the target non-platform region, then when the reference battery cell is charged to the target voltage, at least some or all of the voltages of the multiple battery cells are within the voltage range corresponding to the target non-platform region.

[0175] In this embodiment, by setting the target voltage within the voltage range of any one of the non-platform regions in at least one of the non-platform regions of the battery cell, it is easier to better control the voltage of more battery cells in the battery device to be within the voltage range of any one of the non-platform regions when the reference battery cell is charged to the target voltage. This allows for accurate determination of the charging capacity of multiple battery cells based on their voltages, thereby improving the balancing effect of the battery device.

[0176] In some embodiments, the target voltage includes an upper voltage limit corresponding to a target non-platform region, wherein the target non-platform region is any one of at least one non-platform region.

[0177] That is, in this embodiment, the battery cell may include at least one non-platform region, such as Figure 4 The target voltage can be at the upper limit of the voltage corresponding to any one of the three non-platform zones shown in the first, third and fifth stages.

[0178] As an example, taking the reference battery cell as the one with the highest voltage among multiple battery cells, the target voltage can be the upper limit voltage corresponding to the target non-plateau region. In this way, when the reference battery cell is charged to the target voltage, the voltages of the other battery cells are lower than the target voltage, which can make the voltages of more battery cells fall within the voltage range corresponding to the target non-plateau region as much as possible.

[0179] In this embodiment, by setting the target voltage at the upper limit of the voltage of any one of the non-platform regions in at least one of the non-platform regions of the battery cell, when the reference battery cell with the highest voltage is charged to the target voltage, since the voltage of other battery cells is lower than that of the reference battery cell, the voltage of more or all of the battery cells can fall within the voltage range of the arbitrary non-platform region. Thus, the charging capacity of the battery cell can be accurately determined based on the voltage of the battery cell in the voltage-charging capacity correspondence relationship, thereby improving the balancing effect of the battery device.

[0180] In some embodiments, the target non-platform region includes the last non-platform region among at least one non-platform region, wherein the at least one non-platform region is a non-platform region during the N+1th charging process.

[0181] As an example, such as Figure 4 As shown, if the battery device is charged to the charging cutoff voltage, the individual battery cells can typically undergo [a certain process] during the charging process. Figure 4 The five stages shown are the last stage, which is the last non-platform zone in the charging process.

[0182] The target voltage can be within the voltage range of the last non-platform region (stage 5). For example, the target voltage can be the upper limit of the voltage of the last non-platform region (such as the charging cut-off voltage), or it can be the voltage A of the last non-platform region, or it can be a voltage slightly smaller than voltage A.

[0183] As another example, the battery device can also stop charging when it reaches a voltage below the charging cutoff voltage, such as when it is charged to... Figure 4 The fourth stage of charging is shown as ending at the end of the charging process. In this case, the last non-plateau region during the (N+1)th charging process is... Figure 4 The third stage is shown.

[0184] In this embodiment, the target non-platform region is the last non-platform region in the N+1th charging process, and the target voltage is within the voltage range corresponding to the target non-platform region. In this way, the multiple charging quantities corresponding to multiple battery cells near the end of the charging process can be used as the control and balancing quantities. The closer the charging quantity difference of multiple battery cells is to the end of the charging process, the closer it is to their actual quantity difference. Therefore, precise balancing can be performed based on the multiple charging quantity differences, which can improve the balancing effect of the battery device.

[0185] Optionally, during the N+1th charging process, the last non-platform region can also be... Figure 4 The fifth stage shown is different from the non-plateau region. That is, as the amount of electricity or the amount of electricity charged increases, the voltage gradually increases.

[0186] For example, such as Figure 4 The voltages of the first two non-platform regions shown in the diagram increase, while the voltage of the last non-platform region first increases, then decreases, and then increases again. Therefore, the non-platform region where the voltage of the last non-platform region increases during the (N+1)th charging process is the second non-platform region.

[0187] For example, if the reference cell is the cell with the highest voltage among multiple cells, the target voltage... Figure 4 The upper limit voltage of the second non-platform region is shown.

[0188] In this embodiment, the voltage of the last non-platform zone gradually increases, which can establish a one-to-one correspondence between the voltage and the charged capacity in the last non-platform zone. This allows for accurate determination of the charged capacity corresponding to more battery cells, thereby enabling precise balancing of the battery device and improving the balancing effect of the battery device.

[0189] In some embodiments, the target non-platform region includes the target region of the last non-platform region of at least one non-platform region, the voltage in the target region shows an increasing trend, and the at least one non-platform region is the non-platform region in the N+1th charging process.

[0190] As an example, if the battery device is charged to the charging cutoff voltage, the individual battery cells can typically pass through during the charging process. Figure 4 The five stages shown include the last stage, which is the last non-platform region in the charging process. The target area of ​​this last non-platform region can be the area before voltage A or the area after voltage A.

[0191] In this embodiment, the target non-platform region is defined as the area where the voltage increases in the last non-platform region during the (N+1)th charging process, and the target voltage is within the voltage range corresponding to the target non-platform region. In this way, the charging capacity corresponding to multiple battery cells near the end of charging can be used as the control and balancing capacity. The closer the multiple battery cells are to the end of charging, the closer their corresponding charging capacity in the voltage-charging capacity curve is to their actual capacity. Furthermore, a one-to-one correspondence exists between voltage and charging capacity within the target non-platform region, allowing for accurate determination of the charging capacity corresponding to more battery cells. This enables precise balancing of the battery device and improves its balancing effect.

[0192] Figure 6 This is a schematic flowchart of the battery balancing method provided in an embodiment of this application.

[0193] 610, if the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge, control the battery device to perform the N+1th charge under the target charging conditions.

[0194] As an example, the power in the balanced power and preset balanced power can include capacity or SOC, etc.

[0195] As an example, the balanced charge of the battery device within a preset time period can be determined based on the balanced charge of multiple battery cells within the preset time period, such as the average, maximum, or minimum value of the balanced charge of multiple battery cells.

[0196] As an example, the balanced capacity of the battery device within a preset time period can include the average, maximum, or minimum value of the balanced capacity of multiple battery cells within the preset time period. For instance, the balanced capacity of the battery device within the preset time period can be max(ΔC1, ΔC2, ..., ΔCm), where ΔC1, ΔC2, ..., ΔCm are the balanced capacities of the multiple battery cells within the preset time period, respectively.

[0197] As an example, the balanced charge of the battery device within a preset time period may include the balanced charge when balancing based on the balancing strategy provided in this application. That is, based on the process of controlling the battery device to perform the N+1th charging under the target charging conditions, the voltage-charged charge correspondence of the reference battery cell among the multiple battery cells is determined, and multiple charges corresponding to the voltage of the multiple battery cells at any time are determined to balance the battery device.

[0198] As another example, the equalization charge of the battery device within a preset time period may include equalization charge obtained through other equalization strategies, such as equalization charge obtained by determining the charge of individual battery cells through a laboratory-calibrated voltage-charge correspondence.

[0199] As an example, if the monthly balanced charge of the battery device is less than or equal to the preset balanced charge, the battery device can be controlled to perform the N+1th charge under the target charging conditions.

[0200] If the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge, it means that the battery device's balanced charge within the preset time cannot meet the battery device's balancing requirements. In this case, there is still a significant imbalance in the charge of the multiple battery cells in the battery device, so the battery device needs to be balanced.

[0201] In this embodiment, when the equalization charge of the battery device within a preset time is less than or equal to the preset equalization charge, i.e., when the equalization charge of the battery device within the preset time is insufficient, the battery device can be controlled to perform the N+1th charge under the target charging conditions. Then, by using the correspondence between the voltage and charge of the reference battery cell determined during the N+1th charge, the multiple charges corresponding to the voltages of multiple battery cells during the N+1th charge can be accurately determined. This allows for reasonable and accurate balancing of the battery device based on the multiple charges corresponding to the multiple battery cells, thereby improving the performance and lifespan of the battery device.

[0202] In some embodiments, the battery device may be controlled to perform the Nth charging before it is determined that the balanced charge of the battery device within a preset time is less than or equal to the preset balanced charge; and a target charging condition may be determined based on the charging condition of the Nth charging; and then, if it is determined that the balanced charge of the battery device within a preset time is less than or equal to the preset balanced charge, the battery device may be controlled to perform the N+1th charging under the target charging condition.

[0203] That is, the Nth charge is performed before it is determined that the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge, and the N+1th charge is performed after it is determined that the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge.

[0204] As an example, during each charging process of the battery device, the charging conditions of the battery device, such as the charging capacity range, and at least one of the following within the charging capacity range: charging current, charging rate, or charging temperature.

[0205] Of course, you can retain only the charging conditions from the most recent charge. For example, based on the process of the first charge, record the charging conditions for the first charge; after the second charge, based on the process of the second charge, record the charging conditions for the second charge, and delete the charging conditions from the first charge.

[0206] In this embodiment, the target charging conditions can be determined based on the charging conditions of the Nth charging of the battery device. This allows the battery device to be controlled to perform the N+1th charging under the target charging conditions when the balanced charge of the battery device within a preset time is less than or equal to the preset balanced charge. Furthermore, by establishing the correspondence between the voltage and charge input of the reference battery cell during the N+1th charging process, the multiple charges corresponding to the voltages of the multiple battery cells during the N+1th charging process can be accurately determined. This enables reasonable and precise balancing of the battery device based on the charge input of the multiple battery cells, thereby improving the performance and lifespan of the battery device.

[0207] In some embodiments, if it is determined that the battery device's balanced charge within a preset time is less than or equal to a preset balanced charge, the battery device may be controlled to perform an Nth charge, and the charging conditions of the Nth charge may be recorded; based on the charging conditions of the Nth charge, a target charging condition may be determined.

[0208] That is, in this embodiment, the Nth charge and the N+1th charge are both performed when it is determined that the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge.

[0209] In this embodiment, the charging conditions for the Nth charge of the battery device will only be recorded if the balanced charge of the battery device within a preset time is less than or equal to the preset balanced charge, and the target charging conditions will be determined based on the charging conditions for the Nth charge.

[0210] In this embodiment, when the battery's balanced charge within a preset time is less than or equal to the preset balanced charge, i.e., when the battery's balanced charge within the preset time is insufficient, the battery can be controlled to perform the Nth charging. Then, the target charging conditions are determined based on the charging conditions of the Nth charging. Finally, the battery is controlled to perform the N+1th charging under the target charging conditions. By using the correspondence between the voltage and charge of the reference battery cell determined during the N+1th charging, the multiple charges corresponding to the voltages of multiple battery cells during the N+1th charging can be accurately determined. This allows for reasonable and accurate balancing of the battery based on the charge of multiple battery cells, thereby improving the performance and lifespan of the battery.

[0211] On the other hand, memory charging can only be triggered when the battery device's equalization charge is insufficient within a preset time. That is, the charging conditions will be recorded during the Nth charging process to determine the target charging conditions, which can reduce the data overhead of battery device equalization.

[0212] 620. Based on the process of the battery device performing the N+1th charge under the target charging conditions, determine the correspondence between the voltage and the charge amount of the reference battery cell among the multiple battery cells of the battery device.

[0213] 630. Based on the voltage-charge capacity correspondence, determine the multiple charge capacities corresponding to the voltages of multiple battery cells when the battery device is charged to the target time.

[0214] 640, balances the battery device based on multiple charge levels.

[0215] The content of steps 620 to 640 can be referred to in the relevant descriptions of steps 220 to 240 above, and will not be repeated here.

[0216] In some embodiments, the preset equalization charge is determined based on the difference in self-discharge rate of the battery device over a preset time period.

[0217] The self-discharge rate of a battery device refers to the degree to which the stored electrical charge naturally decreases over time due to spontaneous chemical reactions occurring within the battery when it is at rest.

[0218] As an example, the difference in the self-discharge rate of a battery device can be represented by the percentage decrease in the battery's charge over a preset time period.

[0219] As an example, the difference in self-discharge rate of the battery device within a preset time period can be determined based on the maximum, minimum, or average value of the difference in self-discharge rate among multiple battery cells within the preset time period (such as the average value of the difference between the minimum self-discharge rate among multiple battery cells and the self-discharge rate of other battery cells among multiple battery cells within the preset time period).

[0220] As an example, the difference in self-discharge rate of the battery device within a preset time period may include the maximum, minimum, or average value of the difference in self-discharge rate among multiple individual cells in the battery device within the preset time period.

[0221] For example, the difference in monthly self-discharge rate of the battery device is max(ΔD1, ΔD2, ..., ΔDn), where ΔD1, ΔD2, ..., ΔDn are the differences in monthly self-discharge rate between multiple battery cells (such as other battery cells besides the minimum monthly self-discharge rate) and the battery cell with the minimum monthly self-discharge rate.

[0222] As an example, the self-discharge rate of a single battery cell can be determined based on its charging capacity and its discharge capacity after a preset resting time. For example, self-discharge rate = (charging capacity - discharge capacity after preset resting time) / charging capacity × 100%.

[0223] As an example, the preset equalization charge can be the difference in the self-discharge rate of the battery device within a preset time.

[0224] As an example, the method for determining the preset equalization charge is related to the method for determining the equalization charge of the battery device within a preset time. For instance, if the equalization charge of the battery device within a preset time is determined based on the maximum value of the equalization charge of multiple individual cells in the battery device within the preset time, then the preset equalization charge can be determined based on the maximum value of the monthly self-discharge rate difference of multiple individual cells in the battery device within the preset time.

[0225] In this embodiment of the application, a preset equalization charge can be determined based on the difference in self-discharge rate of the battery device within a preset time, so as to accurately know the equalization requirement of the battery device, so as to equalize the battery device when the equalization charge of the battery device within the preset time cannot meet the equalization requirement.

[0226] In some embodiments, the target charging conditions further include at least one of the following: the charging time corresponding to the charging current, the charging time corresponding to the charging rate, or the charging time corresponding to the charging temperature within the charging capacity range.

[0227] As an example, within the overlapping SOC range of the Nth charge and the N+1th charge, the charging current will change during charging. For example, the first current may be used for the first time, the second current for the second time, and the third current for the third time, until charging is completed.

[0228] In this embodiment, the closer the charging conditions of the Nth charge and the N+1th charge are, the closer the ratio of the charging capacity to the discharging capacity in one charge-discharge cycle of the battery device is to 1. The side reaction consumption of each battery cell in the N+1th charge process is reduced or even eliminated. The amount of electricity charged into each cell is more or almost entirely converted into an increase in electricity, thereby making the voltage-electricity relationship of multiple battery cells more consistent. Only then can the multiple charging capacities corresponding to multiple battery cells be determined based on the voltage-charged electricity correspondence, and the battery device be reasonably balanced.

[0229] In some embodiments, the battery device includes a sodium-ion battery device.

[0230] Sodium-ion battery devices consist of multiple sodium-ion battery cells.

[0231] Sodium-ion battery devices have a high self-discharge rate, and the self-discharge rate varies greatly among individual cells in a sodium-ion battery device. Furthermore, the differences in the charging curves (such as the relationship between voltage and charge) between individual cells are quite significant, for example, the charge of different individual cells varies at the same voltage.

[0232] Traditional balancing strategies based on charging curves, such as those based on pre-calibrated charging curves (e.g., voltage-charged capacity relationship), cannot accurately determine the capacity of individual battery cells, and therefore cannot accurately balance sodium-ion battery devices to meet their balancing requirements.

[0233] In this embodiment, the N+1th charge can be performed based on the charging conditions of the Nth charge, thereby making the voltage-capacity correspondence of multiple sodium-ion battery cells in the sodium-ion battery device closer. Then, by using the voltage-charged capacity correspondence of the reference sodium-ion battery cell determined during the N+1th charge, the multiple charges corresponding to the voltages of multiple sodium-ion battery cells during the N+1th charge can be accurately determined. This cleverly converts the capacity of multiple sodium-ion battery cells into corresponding charges, thereby enabling reasonable balancing of the sodium-ion battery device based on the charges of multiple sodium-ion battery cells to meet the balancing requirements of the sodium-ion battery device and improve its performance and service life.

[0234] In some embodiments, the ratio of the charge capacity to the discharge capacity during a single charge-discharge cycle of the battery device is greater than 1.

[0235] As mentioned above, for battery devices where the ratio of charge capacity to discharge capacity is greater than 1 during a single charge-discharge cycle, and considering the differences between individual cells in the device—such as manufacturing variations, self-discharge rates, state of charge (SOC), temperature differences, and state of health (SOH)—the dynamic inconsistency of side reaction consumption among the cells leads to varying degrees of side reactions during charging. This results in different levels of charge gain for each cell, and consequently, different voltage-charge relationships during charging. In other words, a charge-to-discharge capacity ratio greater than 1 during a single charge-discharge cycle introduces a state-dependent charge loss, and the extent of this loss varies across cells in different states.

[0236] If the battery device performs memory charging, that is, when it is recharged under the charging conditions of the previous charge or similar to the previous charge, the ratio of the charge capacity to the discharge capacity in one charge-discharge cycle will decrease, such as approaching 1. The side reaction consumption in the battery device will decrease or there will be almost no side reaction. More or almost all of the charge in the battery device will be converted into an increase in the amount of charge, thereby making the voltage-charge relationship of the multiple battery cells in the battery device more consistent.

[0237] Therefore, in this embodiment, the battery device can be charged for the N+1th time based on a target charging condition where the difference between the charging conditions of the Nth charge and the charging conditions of the Nth charge is less than or equal to a preset value. This allows the voltage-charge correspondence of multiple battery cells in a battery device where the ratio of the charged capacity to the discharged capacity in one charge-discharge cycle is greater than 1 to be closer. Furthermore, by using the voltage-charge correspondence of the reference battery cell determined in the N+1th charge, the multiple charged capacities corresponding to the voltages of multiple battery cells in the N+1th charge can be accurately determined. This cleverly converts the charge of multiple battery cells where the ratio of the charged capacity to the discharged capacity in one charge-discharge cycle is greater than 1 into the corresponding charged capacity. Thus, the battery device where the ratio of the charged capacity to the discharged capacity in one charge-discharge cycle is greater than 1 can be reasonably balanced based on the charged capacity of multiple battery cells.

[0238] It should be understood that in the various embodiments of this application, the order of the above-mentioned processes does not imply the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this application.

[0239] The battery management system of the embodiments of this application has been described in detail above. The following will be combined with… Figure 7 and Figure 8 The battery management system of the embodiments of this application is described in detail. The technical features described in the method embodiments are applicable to the following embodiments of the battery management system.

[0240] Figure 7 This is a schematic block diagram of the battery management system provided in an embodiment of this application. Figure 7 The battery management system 4000 includes some or all of the following components.

[0241] The battery management system 4000 includes a control unit 4010 and a determination unit 4020.

[0242] Control unit 4010 is used to control the battery device to perform the (N+1)th charge under target charging conditions, wherein the difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value, and the target charging conditions include a charging capacity range and at least one of charging current, charging rate, or charging temperature within the charging capacity range; determining unit 4020 is used to determine the voltage-charged capacity correspondence of a reference battery cell among multiple battery cells in the battery device according to the process of the (N+1)th charge; and to determine multiple charges corresponding to the voltage of the multiple battery cells at any time during the (N+1)th charge process according to the voltage-charged capacity correspondence; control unit 4010 is used to balance the battery device according to the multiple charges.

[0243] In some embodiments, the determining unit 4020 is specifically used to determine, based on the voltage-charge capacity correspondence, multiple charges corresponding to the voltages of multiple battery cells when the reference battery cell is charged to the target voltage, wherein when the reference battery cell is charged to the target voltage, at least a portion of the voltages of the multiple battery cells are within the voltage range corresponding to the non-plateau region of the battery cell.

[0244] In some embodiments, the determining unit 4020 is specifically used to determine the voltage-charged capacity correspondence based on the process of charging the reference battery cell to the target voltage, wherein the reference battery cell is the battery cell with the highest voltage among the plurality of battery cells.

[0245] In some embodiments, the target voltage is within the voltage range corresponding to the target non-platform region, and the target non-platform region is any one of at least one non-platform region.

[0246] In some embodiments, the target voltage includes an upper voltage limit corresponding to a target non-platform region, wherein the target non-platform region is any one of at least one non-platform region.

[0247] In some embodiments, the target non-platform region includes the last non-platform region among at least one non-platform region, and the at least one non-platform region is a non-platform region during the N+1th charging process.

[0248] In some embodiments, the voltage of the last non-plateau region gradually increases.

[0249] In some embodiments, the target non-platform region includes the target region of the last non-platform region in at least one non-platform region, the voltage in the target region shows an increasing trend, and the at least one non-platform region is the non-platform region in the process of the N+1th charging.

[0250] In some embodiments, the target non-plateau region includes the last non-plateau region where the voltage increases during the N+1th charging process.

[0251] In some embodiments, the control unit 4010 is specifically configured to control the battery device to perform the (N+1)th charging under the target charging conditions when the battery device's balanced charge within a preset time is less than or equal to the preset balanced charge.

[0252] In some embodiments, the control unit 4010 is further configured to control the battery device to perform the Nth charge; the determining unit is further configured to determine the target charging conditions based on the charging conditions of the Nth charge.

[0253] In some embodiments, the control unit 4010 is specifically configured to control the battery device to perform the Nth charging when the battery device's balanced charge within a preset time is less than or equal to a preset balanced charge, and to record the charging conditions of the Nth charging; the determining unit 4020 is specifically configured to determine the target charging conditions based on the charging conditions of the Nth charging; and the control unit 4010 is specifically configured to control the battery device to perform the N+1th charging under the target charging conditions.

[0254] In some embodiments, the preset equalization charge is determined based on the difference in self-discharge rate of the battery device over a preset time period.

[0255] In some embodiments, the target charging conditions further include at least one of the following: the charging time corresponding to the charging current, the charging time corresponding to the charging rate, or the charging time corresponding to the charging temperature within the charging capacity range.

[0256] In some embodiments, the battery device includes a sodium-ion battery device.

[0257] In some embodiments, the ratio of the charge capacity to the discharge capacity during a single charge-discharge cycle of the battery device is greater than 1.

[0258] It should be understood that the above and other operations and / or functions of the various modules in the battery management system 4000 are for the purpose of achieving Figures 2 to 6 For the sake of brevity, the corresponding processes in each method will not be elaborated here.

[0259] Figure 8 A schematic block diagram of a battery management system 4000 according to an embodiment of this application is shown. Figure 8 As shown, the battery management system 4000 includes a processor 5010 and a memory 5020, wherein the memory 5020 is used to store instructions, and the processor 5010 is used to read instructions and execute the methods of the various embodiments of the present application based on the instructions.

[0260] The memory 5020 can be a separate device independent of the processor 5010, or it can be integrated into the processor 5010.

[0261] Optionally, such as Figure 8 As shown, the battery management system 4000 may also include a transceiver 5030, and the processor 5010 can control the transceiver 5030 to communicate with other devices. Specifically, it can send information or data to other devices, or receive information or data sent by other devices.

[0262] It should be understood that the processor in the embodiments of this application may be an integrated circuit chip with signal processing capabilities. In implementation, the steps of the above method embodiments can be completed by integrated logic circuits in the processor's hardware or by instructions in software form. The processor described above can be a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components. It can implement or execute the methods, steps, and logic block diagrams disclosed in the embodiments of this application. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the methods disclosed in the embodiments of this application can be directly embodied in the execution of a hardware decoding processor, or executed by a combination of hardware and software modules in the decoding processor. The software modules can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, registers, or other mature storage media in the art. The storage medium is located in memory, and the processor reads information from the memory and, in conjunction with its hardware, completes the steps of the above method.

[0263] It is understood that the memory in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. The non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. The volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM). It should be noted that the memory used in the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

[0264] like Figure 9 As shown in the figure, this application embodiment also provides a battery system 6000, which may include a battery device 6100 and a battery management system 4000.

[0265] The battery device 6100 includes multiple battery cells.

[0266] The battery management system 4000 can be used to perform the battery device balancing method provided in the embodiments of this application.

[0267] For details regarding the battery device 6100 and the battery management system 4000, please refer to the descriptions above. For the sake of brevity, these details will not be repeated here.

[0268] like Figure 10 As shown in the figure, this application embodiment also provides a battery system 6000, which includes a first energy region 6010, a second energy region 6020 and a battery management system 4000.

[0269] The first energy region 6010 is provided with a first battery device 6011, which includes a plurality of first battery cells.

[0270] The second energy region 6020 is provided with a second battery device 6021, which includes a plurality of second battery cells. The first energy region 6010 and the second energy region 6020 are independently provided.

[0271] The battery management system 4000 can control the first battery device 6011 and / or the second battery device 6021 to perform the battery device balancing method provided in the embodiments of this application.

[0272] In this embodiment, the first battery device 6011 and the second battery device 6021 are respectively located in different energy zones, i.e., redundant design is implemented. In this way, for example, if one battery device malfunctions during the use of the electrical device, the other battery device can continue to supply power to the electrical device, and the electrical device can continue to work normally.

[0273] In this embodiment, the battery system may include multiple independent energy zones, each of which is equipped with a battery pack. For example, the battery system may include two independent energy zones, such as a first energy zone and a second energy zone, with a first battery device 6011 and a second battery device 6021 respectively in the two energy zones.

[0274] Energy zones are the parts of a battery system that can operate and be controlled independently. For example, each energy zone can be charged and discharged separately. Specifically, energy zones can be divided according to the configuration of the battery devices in the battery system.

[0275] As an example, each energy zone's battery unit can individually supply power to the load of the electrical device.

[0276] For example, the first battery device 6011 and the second battery device 6021 can supply power to the load of the electrical device independently.

[0277] The first battery device 6011 and the second battery device 6021 can simultaneously supply power to the load of the electrical device. Alternatively, one of the first battery device 6011 and the second battery device 6021 can be used preferentially to supply power to the load of the electrical device, and if the power of one battery device is exhausted or malfunctions, the other battery device can be switched to supply power to the load of the electrical device.

[0278] As another example, one of the first battery device 6011 and the second battery device 6021 can be used to supply power to the load of the electrical device. In this case, the other of the first battery device 6011 and the second battery device 6021 can be used to transfer energy to that first battery device to supply power to it.

[0279] As an example, the first battery device 6011 and the second battery device 6021 can be charged by a charging device.

[0280] As an example, a charging device may include a charging station and / or a charging gun.

[0281] As an example, the first battery device 6011 and the second battery device 6021 can be charged separately or as a whole.

[0282] For example, the charging device can charge the first battery device 6011 and the second battery device 6021 as a whole, such as after the first battery device 6011 and the second battery device 6021 are connected in parallel or in series, and then charged by the charging device.

[0283] For example, the charging device can charge the first battery device 6011 and the second battery device 6021 separately. Alternatively, the charging device may include a first charging device and a second charging device, with the first charging device charging the first battery device 6011 and the second charging device charging the second battery device 6021. The first and second charging devices can also be designed as an integrated unit or as independent units.

[0284] As an example, energy can be transferred between the first battery device 6011 and the second battery device 6021.

[0285] For example, the first battery device 6011 and the second battery device 6021 can be connected via a bidirectional power module. The bidirectional power module is a device or circuit capable of bidirectional energy transfer, such as a direct current / direct current (DC / DC) converter circuit, a flyback transformer, etc.

[0286] For example, the battery system may include a battery management system that can control the charging and discharging of the first battery device 6011 and the second battery device 6021, as well as the energy transfer between the first battery device 6011 and the second battery device 6021.

[0287] For example, the battery system may include two battery management systems, which are used to control the charging and discharging of the first battery device 6011 and the second battery device 6021, respectively. The two battery management systems can communicate with each other, and one battery management system can be used to control the energy transfer between the first battery device 6011 and the second battery device 6021.

[0288] The first battery device 6011 can be a battery pack, a battery module, or a battery assembly formed by electrically connecting individual battery cells. The second battery device 6021 can be a battery pack, a battery module, or a battery assembly formed by electrically connecting individual battery cells.

[0289] Optionally, when the battery system includes one or more battery packs, energy zones can be divided within each battery pack. The first battery device 6011 and the second battery device 6021 can be disposed in different energy zones within each battery pack, and partition beams can be provided between the energy zones to isolate them. Alternatively, when the battery system includes multiple battery packs, each battery pack can be considered as an energy zone, and multiple energy zones can be formed among the multiple battery packs.

[0290] In the embodiments of this application, the first battery device 6011 and the second battery device 6021 may be of the same type or different types. For example, the first battery device 6011 may be a power battery and the second battery device 6021 may be an energy battery; or, the first battery device 6011 may be an energy battery and the second battery device 6021 may be a power battery; or both the first battery device 6011 and the second battery device 6021 may be either power batteries or energy batteries.

[0291] like Figure 11 and Figure 12 As shown in the figure, this application embodiment also provides an electrical device 7000.

[0292] like Figure 11 As shown, the electrical device 7000 includes a load 7100 and a battery system 6000, wherein the battery system 6000 is connected to the load 7100 and is used to supply power to the load 7100.

[0293] As an example, the battery system 6000 is used to provide DC power to the load 7100, the voltage of which is greater than a voltage threshold. That is, the load 7100 is a high-voltage load, and the battery system 6000 can supply high-voltage power to the load 7100.

[0294] As an example, electrical appliances may also include other loads such as low-voltage loads.

[0295] like Figure 12 As shown, the electrical device 7000 includes a first load 7010, a second load 7020, and a battery system 6000. The battery system 6000 is connected to the first load 7010 and the second load 7020, and is used to provide a first DC power to the first load 7010 and a second DC power to the second load 7020, respectively. The voltage of the first DC power is greater than the voltage of the second DC power.

[0296] In other words, the first load is a high-voltage load, and the second load is a low-voltage load. The battery system provides low-voltage power to the first load and high-voltage power to the second load.

[0297] For details on the 6000 battery system, please refer to the above text. Figure 9 and Figure 10 For the sake of brevity, the relevant descriptions in the original document will not be repeated here.

[0298] In this application, "high voltage" and "low voltage" are relative concepts; that is, high voltage involves a voltage higher than low voltage. Generally speaking, the difference between high-voltage and low-voltage related circuits or components is that high-voltage related circuits or components refer to circuits or components that can be directly or indirectly connected to the battery system. This is because the battery system consists of several battery cells, providing a relatively high voltage.

[0299] As will be understood by those skilled in the art, high voltage generally refers to voltages greater than tens of volts, hundreds of volts, or higher. Circuits and components operating at voltages greater than tens of volts, hundreds of volts, or higher can be used or processed. For example, circuits and components operating at voltages greater than 30V AC RMS and less than or equal to 1000V AC RMS, or greater than 60V DC and less than or equal to 1500V DC. Here, V represents volts, AC RMS represents the effective power in the alternating current waveform, and DC represents direct current.

[0300] Low voltage generally refers to voltages of tens of volts, 10 volts, or lower. Low-voltage related circuits or components refer to circuits and components that can use or handle voltages of tens of volts, 10 volts, or lower. For example, circuits and components with a maximum operating voltage of no more than 30V AC RMS or no more than 60V DC. Here, V represents volts, AC RMS represents the effective power in the alternating current waveform, and DC represents direct current.

[0301] This application also provides a computer-readable storage medium for storing computer programs.

[0302] When the computer program is run on a computer, it causes the computer to perform the various methods of the embodiments of this application.

[0303] This application also provides a computer program product, including computer program instructions.

[0304] When the computer program instructions are run on a computer, the computer causes the computer to perform the various methods of the embodiments of this application.

[0305] This application also provides a computer program.

[0306] When the computer program is run on a computer, it causes the computer to perform the various methods of the embodiments of this application.

[0307] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0308] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0309] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection involved in the embodiments of this application may be through some interfaces, and the indirect coupling or communication connection of devices or units may be electrical, mechanical, or other forms.

[0310] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0311] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0312] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, ROM, RAM, magnetic disks, or optical disks.

[0313] Although this application has been described with reference to preferred embodiments, various modifications can be made thereto and components can be replaced with equivalents without departing from the scope of this application. In particular, the technical features mentioned in the various embodiments can be combined in any manner, provided there is no structural conflict. This application is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A method for battery equalization, characterized in that, include: The battery device is controlled to perform the (N+1)th charge under target charging conditions. The difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value. The target charging conditions include a charging capacity range and also include at least one of the charging current, charging rate or charging temperature within the charging capacity range. Based on the N+1th charging process, determine the voltage-charged capacity correspondence of the reference battery cell among the multiple battery cells of the battery device; Based on the voltage-charged capacity correspondence, multiple charged capacities corresponding to the voltage of the plurality of battery cells charged to the target time during the N+1th charging process are determined, wherein at least some of the battery cells have a voltage at the target time that is within the voltage range corresponding to the non-platform of the battery cell. The battery device is balanced based on the multiple charged capacities.

2. The method according to claim 1, characterized in that, Based on the voltage-charge capacity correspondence, determine the multiple charge capacities corresponding to the voltage of the multiple battery cells at the target time during the (N+1)th charging process, including: Based on the voltage-charge capacity correspondence, multiple charge capacities corresponding to the voltage of the plurality of battery cells are determined when the reference battery cell is charged to the target voltage. When the reference battery cell is charged to the target voltage, at least a portion of the voltages of the plurality of battery cells are within the voltage range corresponding to at least one non-plateau region of the battery cell.

3. The method according to claim 2, characterized in that, The step of determining the voltage-charged capacity correspondence of a reference battery cell among the multiple battery cells of the battery device according to the N+1th charging process includes: Based on the process of charging the reference battery cell to the target voltage, the correspondence between voltage and charge is determined, wherein the reference battery cell is the battery cell with the highest voltage among the plurality of battery cells.

4. The method according to claim 2, characterized in that, The target voltage is within the voltage range corresponding to the target non-plateau region, and the target non-plateau region is any one of the at least one non-plateau regions.

5. The method according to claim 3, characterized in that, The target voltage includes the upper limit of the voltage corresponding to the target non-plateau region, and the target non-plateau region is any one of the at least one non-plateau regions.

6. The method according to claim 4, characterized in that, The target non-platform area includes the last non-platform area among the at least one non-platform area, and the at least one non-platform area is the non-platform area during the N+1th charging process.

7. The method according to claim 6, characterized in that, The voltage in the last non-platform region gradually increases.

8. The method according to claim 4, characterized in that, The target non-platform region includes the target region of the last of the at least one non-platform regions, the voltage in the target region shows an increasing trend, and the at least one non-platform region is the non-platform region in the N+1th charging process.

9. The method according to claim 1, characterized in that, The control battery device performs the N+1th charge under target charging conditions, including: If the battery device's balanced charge level within a preset time is less than or equal to the preset balanced charge level, the battery device is controlled to perform the (N+1)th charge under the target charging conditions.

10. The method according to claim 9, characterized in that, Before controlling the battery device to perform the (N+1)th charge under the target charging conditions when the battery device's balanced charge level within a preset time is less than or equal to the preset balanced charge level, the method further includes: Control the battery device to perform the Nth charge; The target charging conditions are determined based on the charging conditions of the Nth charging.

11. The method according to claim 9, characterized in that, When the battery's balanced charge level within a preset time is less than or equal to a preset balanced charge level, controlling the battery to perform the (N+1)th charge under the target charging conditions includes: If the battery device's balanced charge is less than the preset balanced charge within a preset time, the battery device is controlled to perform the Nth charge, and the charging conditions of the Nth charge are recorded. Based on the charging conditions of the Nth charge, determine the target charging conditions; The battery device is controlled to perform the (N+1)th charge under the target charging conditions.

12. The method according to claim 9, characterized in that, The preset equalization charge is determined based on the difference in self-discharge rate of the battery device within the preset time period.

13. The method according to claim 1, characterized in that, The target charging conditions also include at least one of the following: the charging time corresponding to the charging current, the charging time corresponding to the charging rate, or the charging time corresponding to the charging temperature within the charging capacity range.

14. The method according to claim 1, characterized in that, The battery device includes a sodium-ion battery device.

15. The method according to any one of claims 1 to 14, characterized in that, The ratio of the charge capacity to the discharge capacity during a single charge-discharge cycle of the battery device is greater than 1.

16. A battery management system, characterized in that, include: A control unit is configured to control the battery device to perform the (N+1)th charge under target charging conditions, wherein the difference between the target charging conditions and the charging conditions of the Nth charge of the battery device is less than or equal to a preset value, and the target charging conditions include a charging capacity range and further include at least one of the charging current, charging rate or charging temperature within the charging capacity range. The determining unit is used to determine the voltage-charged capacity correspondence of a reference battery cell among the multiple battery cells of the battery device according to the N+1th charging process. as well as Based on the voltage-charged capacity correspondence, determine the multiple charges corresponding to the voltage of the multiple battery cells at the target time during the N+1th charging process, wherein at least some of the multiple battery cells have a voltage at the target time that is within the voltage range corresponding to the non-platform of the battery cell. The control unit is used to balance the battery device according to the plurality of charged charges.

17. A battery management system, characterized in that, include: Memory, used to store programs; A processor for executing a program stored in the memory, wherein when the program stored in the memory is executed, the processor is configured to perform the method of any one of claims 1 to 15.

18. A battery system, characterized in that, include: The battery device includes multiple battery cells; And the battery management system as described in claim 16 or 17.

19. A battery system, characterized in that, include: A first energy zone, wherein a first battery device is provided in the first energy zone, and the first battery device includes a plurality of first battery cells; A second energy region, wherein a second battery device is provided in the second energy region, the second battery device comprising multiple second battery cells, and the first energy region and the second energy region are independently configured; and A battery management system for controlling the first battery device and / or the second battery device to perform the method of any one of claims 1 to 15.

20. An electrical device, characterized in that, include: load; as well as The battery system of claim 18 or 19 is connected to the load for supplying power to the load.

21. An electrical appliance, characterized in that, include: First load; Second load; as well as The battery system of claim 18 or 19, wherein the battery system is connected to the first load to provide a first direct current to the first load, and the battery system is connected to the second load to provide a second direct current to the second load, wherein the voltage of the first direct current is greater than the voltage of the second direct current.

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