Battery charging method, controller, charging and discharging system, storage medium, and vehicle

Abstract

A battery charging method, a controller, a charging and discharging system, a storage medium, and a vehicle. The battery charging method comprises: determining a present state-of-charge condition on the basis of first battery data of a traction battery; and when the present state-of-charge condition is a high state-of-charge condition, determining a target charging current on the basis of a pulse charging strategy, so as to charge the traction battery on the basis of the target charging current.

Description

Battery charging methods, controllers, charging and discharging systems, storage media, and vehicles

[0001] This invention claims priority to Chinese Patent Application No. 202411020770.2, filed on July 29, 2024, entitled "Battery Charging Method, Controller, Charging and Discharging System, Storage Medium and Vehicle", the entire contents of which are incorporated herein by reference. Technical Field

[0002] This invention relates to the field of battery charging technology, and more particularly to a battery charging method, controller, charging and discharging system, storage medium, and vehicle. Background Technology

[0003] The charging capability of a power battery is influenced not only by its materials and structure but also by its charging strategy. During charging, different charging methods and currents lead to varying internal polarization effects and negative electrode potentials, thus impacting charging efficiency and safety. Current technologies typically employ a strategy of gradually decreasing the charging current over time, failing to dynamically adjust the current based on actual conditions to ensure both charging efficiency and safety. Summary of the Invention

[0004] This invention provides a battery charging method, controller, charging and discharging system, storage medium, and vehicle to address the problem of how to improve battery charging efficiency.

[0005] A battery charging method, comprising:

[0006] The current charge condition is determined based on the first battery data of the power battery.

[0007] In response to the current charge condition being a high charge condition, a target charging current is determined based on a pulse charging strategy; and

[0008] The power battery is charged based on the target charging current.

[0009] Optionally, the battery charging method further includes:

[0010] In response to the current charge condition being a low charge condition, a target charging current is determined based on a first constant current charging strategy; and

[0011] The power battery is charged based on the target charging current.

[0012] Optionally, the first battery data includes the current SOC and / or the current voltage.

[0013] Optionally, determining the current charge condition based on the first battery data of the power battery includes:

[0014] In response to the current SOC being less than a first SOC threshold and the current voltage being less than a first voltage threshold, the current charging condition is determined to be a low charging condition.

[0015] Optionally, determining the current charge condition based on the first battery data of the power battery includes:

[0016] In response to the current SOC being greater than or equal to a first SOC threshold, or the current voltage being greater than or equal to a first voltage threshold, the current charging condition is determined to be a high charging condition.

[0017] Optionally, determining the target charging current based on the first constant current charging strategy includes:

[0018] The target constant current charging stage is determined based on the second battery data of the power battery; and

[0019] The first constant current corresponding to the target constant current charging stage is determined as the target charging current.

[0020] Optionally, the target constant current charging stage is the constant current charging stage corresponding to the stage data interval to which the second battery data belongs.

[0021] Optionally, determining the target charging current based on the pulse charging strategy includes:

[0022] The target pulse charging stage is determined based on the second battery data of the power battery; and

[0023] The bidirectional pulse current corresponding to the target pulse charging phase is determined as the target charging current.

[0024] Optionally, the target pulse charging stage is the pulse charging stage corresponding to the stage data interval to which the second battery data belongs.

[0025] Optionally, the stage data range is the SOC threshold range and / or the voltage threshold range.

[0026] Optionally, the battery charging method further includes:

[0027] The current temperature condition is determined based on the third battery data of the power battery;

[0028] In response to the current temperature condition being a low-temperature condition, the power battery is controlled to heat up.

[0029] In response to the current temperature condition being normal temperature, the current charge condition is determined based on the first battery data of the power battery.

[0030] Optionally, the third battery data includes the current temperature.

[0031] Optionally, determining the current temperature condition based on the third battery data from the power battery includes:

[0032] In response to the current temperature being less than a first temperature threshold, the current temperature condition is determined to be a low-temperature condition.

[0033] Optionally, determining the current temperature condition based on the third battery data from the power battery includes:

[0034] In response to the current temperature being greater than or equal to the first temperature threshold, the current temperature condition is determined to be a normal temperature condition.

[0035] Optionally, controlling the temperature rise of the power battery includes:

[0036] The power battery is controlled to self-heat up by adopting the temperature rise control strategy corresponding to the current temperature.

[0037] Optionally, the step of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes:

[0038] In response to the current temperature being less than a second temperature threshold, the power battery is controlled to self-heat up based on a self-heating strategy.

[0039] Optionally, the step of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes:

[0040] In response to the current temperature being greater than or equal to a second temperature threshold, the power battery is controlled to self-heat up based on a self-heating strategy, and the power battery is charged based on a second constant current charging strategy.

[0041] Optionally, charging the power battery based on the second constant current charging strategy includes:

[0042] Based on the current temperature and current state of charge (SOC), determine the second constant current; and

[0043] The power battery is charged based on the second constant current.

[0044] Optionally, determining the second constant current based on the current temperature and the current SOC includes:

[0045] Based on the current temperature, current SOC and constant current mapping data, the second constant current is determined.

[0046] Optionally, the target charging current is less than the safe charging current, which is the charging current corresponding to the first battery data at the lithium plating boundary of the battery.

[0047] A controller includes a memory, a processor, and computer instructions stored in the memory and executable on the processor, wherein the processor implements the battery charging method described above when executing the computer instructions.

[0048] A charging and discharging system, the charging and discharging system comprising a charging and discharging circuit and the aforementioned controller;

[0049] The charging and discharging circuit is used to connect the charging power supply and the power battery; and

[0050] The controller is connected to the charging and discharging circuit and is used to control the operation of the charging and discharging circuit so that the charging power supply charges the power battery.

[0051] Optionally, the charging and discharging circuit includes at least one bridge arm and at least one inductor. Each bridge arm includes an upper bridge power transistor and a lower bridge power transistor connected in series. The connection node between the upper bridge power transistor and the lower bridge power transistor is connected to a first end of the inductor.

[0052] At least one of the upper bridge power transistors is used to connect to the positive terminal of the power battery;

[0053] At least one of the lower bridge power transistors is used to connect to the negative terminal of the power battery; and

[0054] At least one of the inductors has a second end used to connect to a battery node of the power battery, wherein the battery node is a node between two adjacent batteries in the power battery.

[0055] Optionally, the charging and discharging circuit further includes a capacitor, the first end of which is used to connect to the positive terminal of the power battery, and the second end of which is used to connect to the negative terminal of the power battery.

[0056] A computer-readable storage medium storing computer instructions that, when executed by a processor, implement the above-described battery charging method.

[0057] A vehicle includes the aforementioned controller, or the aforementioned charging / discharging system, or the aforementioned computer-readable storage medium.

[0058] The aforementioned battery charging method, controller, charging and discharging system, storage medium, and vehicle determine the current charge condition based on the first battery data. In response to the current charge condition being a high charge condition, a target charging current is determined based on a pulse charging strategy. The power battery is then charged based on the target charging current, which can ensure the charging efficiency of the power battery under high charge conditions and avoid lithium plating, thereby extending the battery life. Attached Figure Description

[0059] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments of the present invention will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0060] Figure 1 is a first flowchart of a battery charging method according to an embodiment of the present invention;

[0061] Figure 2 is a second flowchart of a battery charging method according to an embodiment of the present invention;

[0062] Figure 3 is a flowchart of step S102 in Figure 1;

[0063] Figure 4 is a third flowchart of a battery charging method according to an embodiment of the present invention;

[0064] Figure 5 is a schematic diagram of a charging strategy in one embodiment of the present invention;

[0065] Figure 6 is a schematic diagram of the change of negative electrode potential with SOC under different charging strategies in one embodiment of the present invention;

[0066] Figure 7 is a schematic diagram of the resistance of the self-heating pulse at different frequencies as a function of SOC in one embodiment of the present invention;

[0067] Figure 8 is a schematic diagram of a charging and discharging system according to an embodiment of the present invention. Detailed Implementation

[0068] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0069] The battery charging method provided in this embodiment of the invention is applicable to a charging and discharging system for charging a power battery connected to the system. Here, the charging and discharging system is one capable of both charging and self-heating. In this example, the battery charging method is specifically applicable to a controller (hereinafter referred to as ECU) or battery management system (hereinafter referred to as BMS) within the charging and discharging system, which can control the charging power supply to charge the power battery based on measured data. The charging power supply can be, but is not limited to, a charging pile.

[0070] In one embodiment, as shown in FIG1, a battery charging method is provided. Taking the application of this method in an ECU as an example, the method includes the following steps:

[0071] S101: Determine the current charge condition based on the first battery data of the power battery;

[0072] S102: In response to the current charge condition being a high charge condition, determine the target charging current based on the pulse charging strategy;

[0073] Step S103: Charge the power battery based on the target charging current.

[0074] The first battery data refers to real-time battery data, specifically data used to determine the charging condition. The target charging current is the charging current that needs to be controlled by the charging power supply to charge the power battery.

[0075] The current charge condition is used to reflect the state of charge of the power battery. As an example, the current charge condition can be either a high charge condition or a low charge condition. Here, a high charge condition refers to a condition where the battery has a relatively high charge, and vice versa.

[0076] As an example, in step S101, the ECU can obtain the first battery data of the power battery through the BMS. This first battery data can be, but is not limited to, data such as the current SOC and current voltage of the power battery, which can be used to directly or indirectly calculate its state of charge. The current SOC is the SOC of the power battery detected at the current moment. The current voltage is the voltage across the terminals of the power battery detected at the current moment. The ECU can compare the first battery data with high-charge condition conditions. If the first battery data meets the high-charge condition conditions, the current charge condition is determined to be a high-charge condition; otherwise, if the first battery data does not meet the high-charge condition conditions, the current charge condition is determined to be a low-charge condition. The high-charge condition conditions here are pre-set conditions used to evaluate whether the power battery is in a high-charge condition.

[0077] Among them, the pulse charging strategy is a strategy used to control the power battery to charge based on bidirectional pulse current under high charge conditions.

[0078] As an example, in step S102, when the current charge condition is a high charge condition, the ECU can execute a pulse charging strategy, process the measured data collected by the strategy, determine the bidirectional pulse current of the measured data, and define the bidirectional pulse current as the target charging current corresponding to the high charge condition. After determining the target charging current, the ECU can charge the power battery based on the target charging current. That is, under the high charge condition, the power battery is charged based on the bidirectional pulse current to ensure the charging efficiency of the power battery and avoid the phenomenon of negative electrode lithium plating during the charging process, thereby extending the battery life. The bidirectional pulse current here refers to the interval setting of positive pulse current and negative pulse current. Here, the positive pulse is the pulse whose lower limit voltage of the pulse waveform is greater than a preset threshold (such as 0), and the negative pulse is the pulse whose lower limit voltage of the pulse waveform is less than the preset threshold (such as 0). In addition, the pulse whose lower limit voltage of the pulse waveform is equal to the preset threshold (such as 0) can be defined as a zero pulse. When a power battery is under high charge conditions, the battery polarization effect is more obvious, and the battery can accept a smaller charging current. A slightly larger charging current may cause lithium plating on the negative electrode of the battery, leading to accelerated battery life degradation and even safety issues. At this time, bidirectional pulse current is used as the target charging current. The positive pulse current is used to ensure its charging efficiency, while the interval-set negative pulse current is used to achieve automatic depolarization, so as to avoid lithium plating on the negative electrode of the battery and thus extend the battery life.

[0079] In this example, the bidirectional pulse current refers to the alternating setting of positive and negative pulse currents. Specifically, it can be set to charge based on positive pulse current within a preset period, and to charge based on negative pulse current between two adjacent preset periods. For example, a negative pulse between every two preset periods serves as an automatic depolarization mechanism. The waveform of this bidirectional pulse current can be, but is not limited to, sine waves, square waves, pulses, increasing waves, and decreasing waves, etc., such as a sine wave. The frequency of this bidirectional pulse current is given based on the maximum charging speed obtained without lithium plating. Depending on the application scenario, it can be a fixed frequency or dynamically change with SOC. The frequency selection range for the fixed-frequency pulse includes, but is not limited to, 1Hz, 10Hz, 25Hz, 50Hz, 100Hz, or 200Hz. For example, considering factors such as lithium plating, charging speed, impact on battery aging and lifespan, noise, and stability, the frequency of the fixed-frequency pulse can be 100Hz.

[0080] In this embodiment, the current charge condition is determined based on the first battery data. In response to the current charge condition being a high charge condition, a target charging current is determined based on a pulse charging strategy. The power battery is then charged based on the target charging current, which can ensure the charging efficiency of the power battery under high charge conditions and avoid lithium plating, thereby extending the battery life.

[0081] In one embodiment, the battery charging method further includes:

[0082] In response to the current low charge condition, a target charging current is determined based on a first constant current charging strategy; and the power battery is charged based on the target charging current.

[0083] Among them, the first constant current charging strategy is a strategy used to control the power battery to charge based on the first constant current when the battery is under low charge condition.

[0084] As an example, when the current charge condition is low, the ECU can execute a first constant current charging strategy. This strategy processes the measured data collected to determine the corresponding first constant current, which is then set as the target charging current for the low charge condition. When the battery is in a low charge condition, its state of charge is considered low, and the risk of lithium plating is low. Therefore, the first constant current determined by the first constant current charging strategy is set as the target charging current. After determining the target charging current, the ECU can charge the battery based on this current. In other words, under low charge conditions, the battery is charged based on the first constant current to ensure charging efficiency.

[0085] In one embodiment, the first battery data includes the current SOC and / or the current voltage.

[0086] In one embodiment, determining the current charge condition based on the first battery data includes:

[0087] In response to the current SOC being less than the first SOC threshold and the current voltage being less than the first voltage threshold, the current charging condition is determined to be a low charging condition.

[0088] In one embodiment, determining the current charge condition based on the first battery data includes:

[0089] In response to the current SOC being greater than or equal to a first SOC threshold, or the current voltage being greater than or equal to a first voltage threshold, the current charging condition is determined to be a high charging condition.

[0090] The first SOC threshold is a pre-set SOC threshold used to define different charging conditions, for example, an SOC threshold used to distinguish between low charging conditions and high charging conditions. The first voltage threshold is a pre-set voltage threshold used to define different charging conditions, for example, a voltage threshold used to distinguish between low charging conditions and high charging conditions.

[0091] As an example, the ECU determines the current SOC and current voltage of the power battery from the first battery data, compares the current SOC with a first SOC threshold, and compares the current voltage with a first voltage threshold. When the current SOC is less than the first SOC threshold and the current voltage is less than the first voltage threshold, it can be determined that the state of charge of the power battery is low and the potential difference between the positive and negative terminals of the power battery is small. Therefore, the current charging condition is determined to be a low charging condition. When the current SOC is greater than or equal to the first SOC threshold or the current voltage is greater than or equal to the first voltage threshold, it can be determined that the state of charge of the power battery is high or the potential difference between the positive and negative terminals of the power battery is large. Therefore, the current charging condition is determined to be a high charging condition.

[0092] In this example, the current state of charge (SOC) can be used to determine the current charge condition, or the current voltage can be used to determine the current charge condition, or both the current SOC and the current voltage can be used to determine the current charge condition. The specific method can be determined according to the actual situation.

[0093] In one embodiment, as shown in FIG2, the determination of the target charging current based on the first constant current charging strategy includes:

[0094] S201: Determine the target constant current charging stage based on the second battery data of the power battery;

[0095] S202: Determine the first constant current corresponding to the target constant current charging stage as the target charging current.

[0096] The second battery data is real-time collected battery data, which can be used to determine the charging current of the charging power supply to charge the power battery. The target constant current charging stage is the constant current charging stage that matches the second battery data. As an example, based on the first constant current charging strategy, multiple constant current charging stages are pre-set, and stage evaluation conditions and a first constant current current are set for each constant current charging stage. Here, the stage evaluation conditions are used to evaluate whether the constant current charging stage can be entered, and the first constant current current is the charging current corresponding to the constant current charging stage.

[0097] As an example, when the current charge condition is low, the ECU processes the second battery data based on the first constant current charging strategy corresponding to the low charge condition, determines a first constant current that matches the second battery data, and sets this first constant current as the target charging current. For example, the ECU compares the second battery data with pre-set stage evaluation conditions corresponding to multiple constant current charging stages. If the second battery data matches any stage evaluation condition, the constant current charging stage corresponding to that stage evaluation condition is determined as the target constant current charging stage, and the first constant current corresponding to the target constant current charging stage is then determined as the target charging current. In this example, the pre-set stage evaluation conditions and their corresponding first constant currents for multiple constant current charging stages are different. The corresponding constant current charging stage and first constant current can be determined based on the comparison result between the second battery data and the stage evaluation conditions, and this first constant current is set as the target charging current for the battery.

[0098] In one embodiment, the target constant current charging stage is the constant current charging stage corresponding to the stage data interval to which the second battery data belongs.

[0099] As an example, based on the first constant current charging strategy, multiple constant current charging stages are pre-set, and stage evaluation conditions and a first constant current current are set for each constant current charging stage. The stage evaluation conditions here can be a stage data range, which is a pre-set numerical range used to evaluate whether a certain constant current charging stage can be entered.

[0100] As an example, after acquiring the second battery data of the power battery, the ECU compares the second battery data with the stage data intervals corresponding to multiple constant current charging stages; if the second battery data matches the stage data interval corresponding to a constant current charging stage, the constant current charging stage corresponding to the stage data interval to which the second battery data belongs is determined as the target constant current charging stage, and the first constant current current corresponding to the target constant current charging stage is determined as the target charging current.

[0101] For example, N constant current charging stages are preset, where N≥2. The stage data interval corresponding to the i-th constant current charging stage is X_i, and the first constant current current corresponding to the i-th constant current charging stage is I_i, where i≤N. After receiving the second battery data, the ECU can compare the second battery data with the preset N stage data intervals X_i. If the second battery data is within the third stage data interval X_3, then the third constant current charging stage is determined as the target constant current charging stage, and the first constant current current I_3 corresponding to the target constant current charging stage is determined as the target charging current. The power battery is charged based on the target charging current... and so on, until the power battery is detected to have exited the low charge condition or other charging termination conditions are met, and the charging process ends.

[0102] In one embodiment, as shown in FIG3, step S102 above, namely determining the target charging current based on the pulse charging strategy, includes:

[0103] S301: Determine the target pulse charging stage based on the second battery data of the power battery;

[0104] S302: Determine the bidirectional pulse current corresponding to the target pulse charging phase as the target charging current.

[0105] The target pulse charging stage is the pulse charging stage that matches the data of the second battery. As an example, based on the pulse charging strategy, multiple pulse charging stages are pre-set, and stage evaluation conditions and bidirectional pulse currents are set for each pulse charging stage. Here, the stage evaluation conditions are used to evaluate whether the pulse charging stage can be entered, and the bidirectional pulse current is the charging current of the pulse charging stage.

[0106] As another example, when the current charge condition is a high charge condition, the ECU processes the second battery data based on the pulse charging strategy corresponding to the high charge condition, determines a bidirectional pulse current that matches the second battery data, and sets this bidirectional pulse current as the target charging current. For example, the ECU compares the second battery data with pre-set stage evaluation conditions corresponding to multiple pulse charging stages. If the second battery data matches any stage evaluation condition, the pulse charging stage corresponding to that stage evaluation condition is determined as the target pulse charging stage, and the bidirectional pulse current corresponding to that target pulse charging stage is then determined as the target charging current. In this example, the pre-set stage evaluation conditions and their corresponding bidirectional pulse currents for multiple pulse charging stages are different. The corresponding pulse charging stage and bidirectional pulse current can be determined based on the comparison results between the second battery data and the stage evaluation conditions, and this bidirectional pulse current is set as the target charging current for the battery.

[0107] In one embodiment, the target pulse charging stage is the pulse charging stage corresponding to the stage data interval to which the second battery data belongs.

[0108] As an example, based on the pulse charging strategy, multiple pulse charging stages are pre-set, and stage evaluation conditions and bidirectional pulse currents are set for each pulse charging stage. The stage evaluation conditions here can be stage data ranges, which are pre-set numerical ranges used to evaluate whether a certain pulse charging stage can be entered.

[0109] As an example, after acquiring the second battery data of the power battery, the ECU can compare the second battery data with the stage data intervals corresponding to multiple pulse charging stages. If the second battery data matches the stage data interval corresponding to any pulse charging stage, the pulse charging stage corresponding to the stage data interval to which the second battery data belongs is determined as the target pulse charging stage, and the bidirectional pulse current corresponding to the target pulse charging stage is determined as the target charging current.

[0110] For example, N pulse charging stages are preset, where N≥2. The stage data interval corresponding to the i-th pulse charging stage is X_i, and the bidirectional pulse current corresponding to the i-th pulse charging stage is I_i, where i≤N. After receiving the second battery data, the ECU can compare the second battery data with the preset N stage data intervals X_i. If the second battery data is within the third stage data interval X_3, the bidirectional pulse current I_3 corresponding to the third pulse charging stage is determined as the target charging current, and the power battery is charged based on the target charging current... and so on, until the high-charge condition is exited or other charging termination conditions are met, thus ending the charging process.

[0111] In one embodiment, the stage data range is the SOC threshold range and / or the voltage threshold range.

[0112] The SOC threshold interval is a pre-set SOC threshold used to evaluate whether the second battery data falls within a certain charging stage. Each SOC threshold interval corresponds to a lower SOC threshold and an upper SOC threshold. The charging stage here can be a constant current charging stage or a pulse charging stage. Since the battery charge gradually increases during the charging process, in two adjacent charging stages, the lower SOC threshold corresponding to the previous charging stage and the upper SOC threshold corresponding to the next charging stage are the same, serving as the boundary SOC threshold between two adjacent charging stages.

[0113] As an example, the SOC threshold ranges corresponding to multiple constant current charging stages increase sequentially, while the corresponding first constant current current decreases sequentially. For instance, the ECU can compare the current SOC in the second battery data with the SOC threshold range corresponding to the (i-1)th constant current charging stage. If the current SOC is within the SOC threshold range corresponding to the (i-1)th constant current charging stage, then the first constant current current I_(i-1) corresponding to the (i-1)th constant current charging stage is determined as the target charging current. The processing between multiple pulse charging stages is the same as above, and will not be elaborated here to avoid repetition.

[0114] The voltage threshold intervals are pre-set voltage thresholds used to evaluate whether the second battery data falls within a certain charging stage. Each voltage threshold interval corresponds to a lower voltage threshold and an upper voltage threshold. The charging stage here can be a constant current charging stage or a pulse charging stage. Since the battery voltage gradually increases during the charging process, in two adjacent charging stages, the lower voltage threshold corresponding to the previous charging stage and the upper voltage threshold corresponding to the next charging stage are the same, serving as the boundary voltage threshold between two adjacent charging stages.

[0115] As an example, the voltage threshold ranges corresponding to multiple pulse charging stages increase sequentially, while the corresponding bidirectional pulse currents decrease sequentially. For instance, the ECU can compare the current voltage in the second battery data with the voltage threshold range corresponding to the i-th pulse charging stage. If the current voltage is within the voltage threshold range corresponding to the i-th pulse charging stage, then the bidirectional pulse current corresponding to the i-th pulse charging stage is determined as the target charging current. The processing between multiple constant current charging stages is the same as above, and will not be elaborated here to avoid repetition.

[0116] In one embodiment, as shown in FIG4, the battery charging method further includes:

[0117] S401: Determine the current temperature condition based on the third battery data of the power battery;

[0118] S402: In response to the current temperature condition being a low-temperature condition, control the power battery temperature to rise;

[0119] S403: In response to the current temperature condition being normal temperature condition, determine the current charge condition based on the first battery data of the power battery.

[0120] The third battery data consists of real-time collected battery data, specifically data used to determine the temperature operating conditions. The current temperature operating condition reflects the temperature state of the power battery. As an example, the current temperature operating condition can be either a normal temperature condition or a low temperature condition. Here, the normal temperature condition refers to a condition that has not reached the low temperature standard, while the low temperature condition refers to a condition that has reached the low temperature standard.

[0121] As an example, in step S401, the ECU can obtain the third battery data of the power battery and evaluate whether it meets the low temperature standard based on the third battery data. If the third battery data does not meet the low temperature standard, its current temperature condition can be determined to be the normal temperature condition; otherwise, if the third battery data meets the low temperature standard, its current temperature condition can be determined to be the low temperature condition.

[0122] As an example, in step S402, when the current temperature condition is a low-temperature condition, the ECU can determine that the power battery temperature is low. Directly charging the power battery would lead to a high risk of lithium plating on the negative electrode. Therefore, a pre-set temperature control strategy needs to be executed to control the power battery temperature, thereby increasing the cell temperature and helping to ensure subsequent charging efficiency and reduce the risk of lithium plating on the negative electrode. In this example, controlling the power battery temperature can be achieved using, but is not limited to, DC self-heating via the battery's internal resistance, AC self-heating, or an external heating device. After controlling the power battery temperature, the ECU can repeatedly execute step S401, repeatedly acquiring the third battery data and determining the current temperature condition based on the third battery data, until the current temperature condition is determined to be a normal temperature condition.

[0123] As an example, in step S403, when the current temperature condition is normal temperature, the ECU can determine that the temperature of the power battery is higher than the preset low temperature standard. At this time, the risk of low-temperature lithium plating is low, and step S101 and subsequent steps can be executed. That is, it is necessary to obtain the first battery data of the power battery so as to determine the current charge condition based on the first battery data, and then adopt different charging strategies to charge, so as to achieve constant current charging under low charge condition and pulse charging under high charge condition. This can ensure charging efficiency and avoid lithium plating on the negative electrode induced by low temperature, high charge and other conditions.

[0124] In one embodiment, the third battery data includes the current temperature.

[0125] In one embodiment, step S401, namely determining the current temperature condition based on the third battery data of the power battery, includes:

[0126] In response to the current temperature being lower than a first temperature threshold, the current temperature condition is determined to be a low-temperature condition.

[0127] In one embodiment, step S401, namely determining the current temperature condition based on the third battery data of the power battery, includes:

[0128] In response to the current temperature being greater than or equal to a first temperature threshold, the current temperature condition is determined to be a normal temperature condition.

[0129] The current temperature refers to the temperature of the power battery detected at the current moment. The first temperature threshold is a pre-set temperature threshold used to distinguish between normal temperature operating conditions and low temperature operating conditions. For example, it can be a temperature threshold used to assess whether the low temperature standard has been met. For instance, the first temperature threshold can be set to 10℃ or 15℃.

[0130] As an example, the ECU can obtain the current temperature of the power battery and compare it with a first temperature threshold. If the current temperature is lower than the first temperature threshold, the current temperature of the power battery can be considered to have reached the low-temperature standard, and its current temperature operating condition can be determined as a low-temperature operating condition. If the current temperature is greater than or equal to the first temperature threshold, the current temperature of the power battery can be considered to have not reached the low-temperature standard, and its current temperature operating condition can be determined as a normal temperature operating condition. In this example, the corresponding current temperature operating condition can be quickly determined based on the comparison result between the current temperature and the first temperature threshold.

[0131] In one embodiment, controlling the temperature rise of the power battery includes:

[0132] A temperature rise control strategy corresponding to the current temperature is adopted to control the self-heating rise of the power battery.

[0133] As an example, the system pre-sets multiple temperature control strategies, each corresponding to a temperature range and a specific temperature control strategy within that range for controlling battery temperature rise. After acquiring the current temperature of the power battery, the ECU compares this current temperature with the multiple temperature ranges to determine the appropriate temperature control strategy for that range. The ECU then executes this strategy, controlling the power battery to enter a self-heating mode to raise its temperature. This self-heating mode utilizes internal components of the battery pack for self-heating, specifically controlling internal resistors for both DC and AC self-heating. For instance, if the charging / discharging system includes a charging / discharging circuit connected to the power battery, the operation of this circuit can cause the power battery to enter self-heating mode.

[0134] In this example, the charging and discharging circuit divides the power battery into two battery packs connected in series, designated as the first battery pack and the second battery pack, respectively. In self-heating mode, the first battery pack is controlled to discharge and charge the second battery pack, and then the second battery pack is controlled to discharge and charge the first battery pack. By interleaving the charging and discharging of the two battery packs, continuous, safe, stable, and efficient self-heating is achieved while ensuring a stable total voltage and continuous current for both battery packs. Compared to currently widely used external heating methods such as PTC heating, heating films, and DC heat pumps, which suffer from slow heating speed, low heating efficiency, and are prone to uneven heating of the power battery, this heating method, which controls the power battery itself to charge and discharge to raise its temperature, effectively improves its heating efficiency, avoids uneven heating, and enhances its overall temperature rise.

[0135] In one embodiment, the step of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes:

[0136] In response to the current temperature being lower than the second temperature threshold, the power battery is controlled to self-heat up based on a self-heating strategy.

[0137] In one embodiment, the step of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes:

[0138] In response to the current temperature being greater than or equal to the second temperature threshold, the power battery is controlled to heat up based on a self-heating strategy, and the power battery is charged based on a second constant current charging strategy.

[0139] The second temperature threshold is a pre-set temperature threshold used to distinguish between normal low-temperature operating conditions and ultra-low-temperature operating conditions. The second temperature threshold is lower than the first temperature threshold and can be set to -20℃. As an example, when the ECU needs to control the temperature rise of the power battery because the current temperature is lower than the first temperature threshold, it needs to further compare the current temperature with the second temperature threshold in order to implement different measures based on the comparison result.

[0140] The self-heating strategy is a strategy to control the battery's self-heating and temperature rise under low-temperature conditions. The second constant-current charging strategy is a strategy to control the battery to charge based on a constant current under low-temperature conditions.

[0141] As an example, when the current temperature is lower than the second temperature threshold, the ECU determines that the cell temperature of the power battery is in an ultra-low temperature condition, the activity of the internal materials of the power battery is low, the risk of negative electrode lithium plating during the charging process is high, and the charging effect is poor. At this time, a self-heating strategy can be implemented to control the power battery to self-heat up. Specifically, the charging and discharging circuit is controlled to complete the self-heating operation to improve the activity of the internal materials of the power battery and avoid the phenomenon of negative electrode lithium plating during the subsequent charging process.

[0142] As an example, when the current temperature is greater than or equal to a second temperature threshold (i.e., the current temperature is between the second and first temperature thresholds), the ECU determines that the battery cell temperature is under normal low-temperature conditions. While controlling the battery's self-heating based on a self-heating strategy, the ECU processes the measured data based on a second constant-current charging strategy to determine a second constant-current current. The ECU then charges the battery based on this second constant-current current to ensure charging efficiency. In other words, when under normal low-temperature conditions, the ECU can put the battery into a self-heating mode combined with a constant-current charging mode, controlling the charging and discharging circuit to self-heat and obtain the self-heating current corresponding to the self-heating mode. Based on the second constant-current charging strategy, it determines the corresponding first constant-current current, and the self-heating current and the first constant-current current are coupled and superimposed to determine the final target charging current flowing through the battery. This avoids the risk of lithium plating on the negative electrode while ensuring charging efficiency.

[0143] In one embodiment, charging the power battery based on a second constant current charging strategy includes:

[0144] Based on the current temperature and current SOC, determine the second constant current; and based on the second constant current, charge the power battery.

[0145] As an example, the ECU charges the power battery based on a second constant current charging strategy. This includes dynamically determining a constant current matching the current temperature and current SOC, using this as the second constant current, and controlling the charging power supply to charge the power battery based on this second constant current to ensure charging efficiency while avoiding lithium plating on the negative electrode. In this example, the ECU can read a preset constant current determination rule, using the current temperature and current SOC as input parameters for the rule, and determine the second constant current according to the rule. This allows the ECU to control the charging power supply to charge the power battery based on the second constant current, ensuring charging efficiency while avoiding lithium plating on the negative electrode.

[0146] In one embodiment, determining the second constant current based on the current temperature and the current state of charge (SOC) includes:

[0147] The second constant current is determined based on the mapping data of current temperature, current SOC and constant current.

[0148] Among them, the constant current mapping data is a pre-set data to reflect the correspondence between temperature, SOC and constant current. The corresponding constant current can be determined according to different combinations of temperature and SOC. The constant current is pre-tested to ensure charging efficiency and avoid lithium plating on the negative electrode.

[0149] As an example, the ECU charges the power battery based on the second constant current charging strategy, which includes using the current temperature, current SOC and pre-set constant current mapping data to record a constant current that matches the current temperature and current SOC as the second constant current. The ECU then controls the charging power supply to charge the power battery based on the second constant current to ensure its charging efficiency and avoid lithium plating on the negative electrode.

[0150] In one embodiment, the target charging current is less than the safe charging current, which is the charging current corresponding to the first battery data at the lithium plating boundary of the battery.

[0151] The lithium plating boundary is a pre-defined data table used to evaluate the mapping relationship between different battery data and their safe charging current. The safe charging current here is the maximum charging current that the charging power supply can provide to the power battery under a certain operating condition. Understandably, if the charging current provided by the charging power supply to the power battery exceeds this maximum charging current, lithium plating is highly likely to occur. Therefore, in practical applications, it is necessary to ensure that the target charging current of the charging and discharging system is less than its safe charging current to avoid lithium plating on the negative electrode due to excessive charging current.

[0152] As an example, the ECU needs to compare the target charging current determined based on the first constant current charging strategy or pulse charging strategy with the safe charging current. If the target charging current is less than the safe charging current, the power battery can be charged based on the target charging current to ensure charging safety, avoid negative electrode lithium plating, and thus extend battery life.

[0153] As an example, after acquiring the first battery data of the power battery, the ECU can compare the first battery data with multiple pre-set stage data intervals corresponding to various charging stages. If the first battery data falls within any stage data interval, the charging stage corresponding to that stage data interval is determined as the target charging stage; then, the charging current corresponding to that target charging stage is determined as the target charging current. In this example, multiple stage data intervals and charging currents corresponding to various charging stages are pre-set to facilitate subsequent staged charging. That is, based on the stage data interval to which the first battery data belongs, the corresponding target charging current is determined to ensure that each charging stage is charged based on a preset charging current, thereby guaranteeing charging efficiency. When the current charge condition determined based on the first battery data is a low charge condition, the charging stage is a constant current charging stage, and the corresponding charging current is the first constant current current; when the current charge condition determined based on the first battery data is a high charge condition, the charging stage is a pulse charging stage, and the corresponding charging current is a bidirectional pulse current. Generally, when setting multiple charging stages and corresponding data ranges and charging currents in advance, it is necessary to ensure that the charging current corresponding to each data range is less than the safe charging current corresponding to that data range. This is to ensure that the target charging current determined later is less than the corresponding safe charging current, thereby avoiding lithium plating in the power battery and extending battery life.

[0154] For example, the lithium plating boundary is a mapping curve used to reflect the decrease in safe charging current as the battery's state of charge (SOC) increases. It can be divided into multiple charging stages based on different SOC thresholds. Each charging stage corresponds to a data interval defined by two adjacent SOC thresholds; that is, each SOC threshold interval corresponds to a lower SOC threshold and an upper SOC threshold. When setting the charging current for multiple charging stages, the charging current corresponding to the upper SOC threshold in each stage's data interval can be set to be less than its corresponding safe charging current. The charging current corresponding to other SOCs within that stage's data interval should be less than or equal to the charging current corresponding to the upper SOC threshold. This ensures that the charging current for the entire charging stage is less than its corresponding safe charging current, helping to prevent lithium plating in the power battery and thus extending battery life.

[0155] For example, the ECU can acquire the first battery data of the power battery, which includes, but is not limited to, the current SOC, current voltage, and current temperature. Based on the current SOC and current voltage, the current charge condition can be determined. When the current SOC is less than the first SOC threshold and the current voltage is less than the first voltage threshold, it is determined that the high charge condition is not met, and the current charge condition is determined to be a low charge condition. Multiple constant current charging stages can be started sequentially. During the charging process based on the first constant current corresponding to the i-th constant current charging stage, if the detected current SOC is in the SOC threshold range of the (i+1)-th constant current charging stage, or the current voltage is in the voltage threshold range of the (i+1)-th constant current charging stage, it is determined that the process can jump to the (i+1)-th constant current charging stage, and the first constant current corresponding to the (i+1)-th constant current charging stage is determined as the target charging current. Similarly, when the current SOC is greater than or equal to the first SOC threshold, or the current voltage is greater than or equal to the first voltage threshold, it is determined that the high charge condition is met, and the current charge condition is determined to be a high charge condition. Multiple pulse charging stages can be started sequentially. During the charging process based on the bidirectional pulse current corresponding to the j-th pulse charging stage, if the detected current SOC is in the SOC threshold range corresponding to the j+1 pulse charging stage, or the current voltage is in the voltage threshold range corresponding to the j+1 pulse charging stage, it is determined that the process can jump to the j+1 pulse charging stage, and the pulse charging current corresponding to the j+1 pulse charging stage is determined as the target charging current. As shown in Figure 5, multiple voltage thresholds V1, V2, V3...Vn can be preset, with two adjacent voltage thresholds defining the voltage threshold range corresponding to a certain charging stage; and multiple SOC thresholds SOC1, SOC2, SOC3...SOCn can be set, with two adjacent SOC thresholds defining the SOC threshold range corresponding to a certain charging stage. For the i-th charging stage, the corresponding voltage threshold range is [Vi, Vi+1), the corresponding SOC threshold range is [SOCi, SOCi+1), and the corresponding charging current is Ii. When the charging reaches the trigger condition, it automatically switches to the next charging stage, and the current jumps to Ii+1. Optionally, this trigger condition includes, but is not limited to, the current SOC reaching the SOC threshold range corresponding to the next stage, or the current voltage reaching the voltage threshold range corresponding to the next stage. A current jump event is triggered when either condition is met.

[0156] Figure 5 illustrates a bidirectional pulse charging strategy. The dashed line represents the lithium plating boundary of the battery with respect to the state of charge (SOC) at a certain temperature. When the power battery is under low SOC conditions, the first constant current corresponding to multiple constant current charging stages, and when under high SOC conditions, the bidirectional pulse current corresponding to multiple pulse charging stages, are all within the lithium plating boundary. Using the charging strategy shown in Figure 5 can significantly reduce the risk of lithium plating. For example, when the power battery meets the high SOC conditions, multi-step pulse charging can be performed based on the bidirectional pulse currents corresponding to multiple pulse charging stages. Four different pulse charging stages are defined, each with a different bidirectional pulse current. This scheme only shows four different stages; multiple different pulse charging stages can be used depending on actual needs. Furthermore, the span of the SOC threshold range and / or voltage threshold range for these different pulse charging stages can be the same or different. The enlarged views of the pulse waveforms are shown in the two sub-figures in the lower left corner. This scheme illustrates sine waves (left) and square waves (right), while the waveforms of the bidirectional pulse current in this example include, but are not limited to, sine waves, square waves, triangular waves, exponential waves, sawtooth waves, and composite waveforms. The frequency, duty cycle, and amplitude of these waveforms can be adjusted according to actual conditions. Here, the pulse regime is defined as follows: pulses with a lower limit current below 0 are named "negative pulses," pulses with a lower limit voltage equal to 0 are named "zero pulses," and pulses with a lower limit voltage greater than 0 are named "positive pulses." Different pulse regimes, such as "negative pulses," "zero pulses," or "positive pulses," can be selected as needed. Furthermore, during the charging process, the frequency, duty cycle, amplitude, and pulse regime can remain constant or continuously change and adaptively adjust.

[0157] Figure 6 illustrates the variation of the negative electrode lithium potential with state of charge when using this charging strategy. When the power battery is under high charge conditions, the frequencies of the multi-step pulse charging state are set to 20Hz, 50Hz and 100Hz respectively, and a control group (no pulse) is set up. The variation of the negative electrode potential with SOC is detected. It is found that the negative electrode potential is always higher than 0, which means that lithium plating has not occurred. It can also be found that the higher the frequency, the higher the negative electrode potential. This rule can be used to formulate the charging strategy.

[0158] Figure 7 shows the resistance values ​​measured by self-heating pulse charging experiments at different frequencies as a function of SOC. It is easy to understand that the resistance value of the power battery (the resistance value in the figure is the normalized resistance value) remains basically unchanged as the SOC changes. However, compared with charging without pulses, the battery resistance value decreases significantly after introducing self-heating pulses. This indicates that self-heating pulses have a significant effect on depolarization, which can delay the time to reach the cutoff voltage, allowing for higher current charging and reducing charging time. The higher the frequency, the lower the resistance value, and the more significant the depolarization effect.

[0159] It should be understood that the sequence number of each step in the above embodiments 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 the present invention.

[0160] In one embodiment, a controller is provided, including a memory, a processor, and computer instructions stored in the memory and executable on the processor. When the processor executes the computer instructions, it implements the battery charging method described in the above embodiment, such as steps S101-S103 shown in FIG1, or as shown in FIG2-FIG4. To avoid repetition, these will not be described again here.

[0161] In one embodiment, a charging and discharging system is provided, which includes a charging and discharging circuit and a controller as described in the above embodiment; the charging and discharging circuit is used to connect a charging power supply and a power battery; the controller is connected to the charging and discharging circuit and is used to control the operation of the charging and discharging circuit so that the charging power supply charges the power battery.

[0162] The charging / discharging circuit is used to control charging or discharging. This circuit is located between the charging power supply and the power battery, controlling the charging power supply to charge the power battery and controlling the power battery to discharge to the electrical load. This charging / discharging circuit can achieve both constant current charging and pulse charging. For example, it can be implemented using, but is not limited to, a DC-DC converter or other circuits capable of pulse charging.

[0163] As an example, the charging and discharging circuit is used to connect the charging power supply and the power battery. The controller is connected to the charging and discharging circuit and can determine the target charging current based on the first battery data corresponding to the power battery collected in real time. It controls the charging power supply to charge the power battery based on the target charging current. Since the target charging current is less than the safe charging current corresponding to the lithium plating boundary of the battery, the power battery is charged based on the target charging current, which effectively avoids the phenomenon of negative electrode lithium plating in the power battery during the charging process due to excessive charging current, thereby extending the battery life.

[0164] In one embodiment, the charging and discharging circuit includes at least one bridge arm and at least one inductor L1. Each bridge arm includes an upper bridge power transistor T1 and a lower bridge power transistor T2 connected in series. The connection node between the upper bridge power transistor T1 and the lower bridge power transistor T2 is connected to the first end of an inductor L1.

[0165] At least one upper-bridge power transistor T1 is used to connect to the positive terminal of the power battery, at least one lower-bridge power transistor T2 is used to connect to the negative terminal of the power battery, and the second end of at least one inductor L1 is used to connect to the inter-cell node of the power battery, wherein the inter-cell node is the node between two adjacent cells in the power battery.

[0166] As an example, the charging and discharging circuit includes at least one bridge arm and at least one inductor L1. Each bridge arm includes an upper bridge power transistor T1 and a lower bridge power transistor T2 connected in series. The connection node between the upper bridge power transistor T1 and the lower bridge power transistor T2 is the midpoint of the bridge arm. The midpoint of each bridge arm is connected to the first end of an inductor L1. At least one upper bridge power transistor T1 can be connected to the positive terminal of the power battery through a first switch K1, and at least one lower bridge power transistor T2 can be connected to the negative terminal of the power battery through a second switch K2. The second end of at least one inductor L1 can be connected to the inter-cell node of the power battery through a third switch K3. The inter-cell node is the node between two adjacent cells in the power battery.

[0167] When the power battery is divided into a first battery pack and a second battery pack based on the battery inter-node connected to the first inductor L1, the working process of the charging and discharging system entering the self-heating mode is as follows: (1) Control the first switch K1, the upper bridge power transistor T1 and the third switch K3 to be turned on, and the lower bridge power transistor T2 to be turned off, so that the first heating circuit formed by the first battery pack and the inductor L1 is turned on, the first battery pack is discharged, and the second battery pack is charged through the freewheeling diode connected in parallel with the lower bridge power transistor T2; (2) Control the second switch K2, the lower bridge power transistor T2 and the third switch K3 to be turned on, and the upper bridge power transistor T1 to be turned off, so that the second heating circuit formed by the second battery pack and the inductor L1 is turned on, the second battery pack is discharged, and the first battery pack is charged through the freewheeling diode connected in parallel with the upper bridge power transistor T1. In this example, by controlling the on and off of the first switch K1, the second switch K2, the third switch K3, the upper bridge power transistor T1 and the lower bridge power transistor T2, the power battery can realize self-heating operation. The circuit structure is simple, the cost is low, and it can meet different needs.

[0168] In this example, the power battery is connected to the charging power supply via a first switch K1 and a second switch K2, and to the charging and discharging circuit via the first switch K1, the second switch K2, and the third switch K3. When all the switches are on, a second constant current is determined based on a second constant current charging strategy. The charging power supply is then controlled to charge the power battery based on this second constant current, and the charging and discharging circuit is simultaneously controlled to operate, enabling the power battery to perform self-heating. This allows self-heating and charging to occur simultaneously. Furthermore, the charging and discharging circuit does not require a third-party charging pile or energy storage components, making it simple and efficient. The controller here is configured to control the multi-phase bridge arm and the on / off state of the switches to enable the first and second battery packs to alternately charge and discharge, achieving continuous, safe, stable, and efficient self-heating while ensuring a stable total voltage and uninterrupted current for both battery packs.

[0169] In one embodiment, the charging and discharging circuit further includes a capacitor C1, the first end of which is used to connect to the positive terminal of the power battery, and the second end of the capacitor C2 is used to connect to the negative terminal of the power battery.

[0170] As an example, the charging and discharging circuit also includes a capacitor C1, with its two ends connected to the positive and negative terminals of the power battery, respectively. During the alternating charging and discharging process of the power battery through the first and second battery packs, the capacitor C2 can store energy and discharge to cooperate with the power battery in completing the self-heating operation.

[0171] As shown in Figure 8, the power battery is divided into two half-packs, namely the first battery pack 810 and the second battery pack 820. A voltage sensor 830, a current sensor 840, and a temperature sensor 850 are installed between the two battery packs to monitor the state changes of the charging and discharging system in real time, so as to control the charging and discharging based on the detected data from the first battery. In this example, the BMS 860 is connected to the voltage sensor 830, current sensor 840, and temperature sensor 850 to collect data from the first battery. A fuse 870 is connected between the power battery and the charging and discharging circuit to protect the circuit from short circuits and damage to circuit components. The part in the right box of Figure 8 is the charging and discharging circuit, which can be understood as a pulse charging start controller, used to execute commands issued by the BMS, so that the magnitude and direction of the current in the circuit change according to the control strategy. This device does not require a third-party charging pile or energy storage component, making it simple and efficient. This solution comprehensively considers safety and charging speed, is highly efficient and economical, and has high versatility.

[0172] In one embodiment, a computer-readable storage medium is provided, on which computer instructions are stored. When executed by a processor, the computer instructions implement the battery charging method described in the above embodiment, such as steps S101-S103 shown in FIG1, or as shown in FIG2-FIG4. To avoid repetition, these will not be described again here.

[0173] In one embodiment, a vehicle is provided, including the controller, the charging and discharging system, or the computer-readable storage medium described in the above embodiments. To avoid repetition, these will not be described again here.

[0174] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. This computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, storage, databases, or other media used in the embodiments provided in this application can include non-volatile and / or volatile memory. Non-volatile memory may include 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. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, 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 (DDRSDRAM), Enhanced Synchronous Dynamic Random Access Memory (ESDRAM), Synchronous Link Dynamic Random Access Memory (SLDRAM), Rambus Dynamic Random Access Memory (RDRAM), Direct Rambus Dynamic Random Access Memory (DRDRAM), and Rambus Dynamic Random Access Memory (RDRAM), etc.

[0175] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the above-described division of functional units and modules is used as an example. In practical applications, the above functions can be assigned to different functional units and modules as needed, that is, the internal structure of the device can be divided into different functional units or modules to complete all or part of the functions described above.

[0176] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included within the protection scope of the present invention.

Claims

1. A battery charging method, characterized in that, include: The current charge condition is determined based on the first battery data of the power battery. In response to the current charge condition being a high charge condition, the target charging current is determined based on a pulse charging strategy; as well as The power battery is charged based on the target charging current.

2. The battery charging method according to claim 1, characterized in that, The battery charging method further includes: In response to the current charge condition being a low charge condition, a target charging current is determined based on a first constant current charging strategy; and The power battery is charged based on the target charging current.

3. The battery charging method according to claim 2, characterized in that, The first battery data includes the current SOC and / or the current voltage.

4. The battery charging method according to claim 3, characterized in that, The determination of the current charge condition based on the first battery data of the power battery includes: In response to the current SOC being less than a first SOC threshold and the current voltage being less than a first voltage threshold, the current charging condition is determined to be a low charging condition.

5. The battery charging method according to claim 3, characterized in that, The determination of the current charge condition based on the first battery data of the power battery includes: In response to the current SOC being greater than or equal to a first SOC threshold, or the current voltage being greater than or equal to a first voltage threshold, the current charging condition is determined to be a high charging condition.

6. The battery charging method according to claim 2, characterized in that, The determination of the target charging current based on the first constant current charging strategy includes: The target constant current charging stage is determined based on the second battery data of the power battery; and The first constant current corresponding to the target constant current charging stage is determined as the target charging current.

7. The battery charging method according to claim 6, characterized in that, The target constant current charging stage is the constant current charging stage corresponding to the stage data interval to which the second battery data belongs.

8. The battery charging method according to claim 1, characterized in that, The determination of the target charging current based on the pulse charging strategy includes: The target pulse charging stage is determined based on the second battery data of the power battery; and The bidirectional pulse current corresponding to the target pulse charging phase is determined as the target charging current.

9. The battery charging method according to claim 8, characterized in that, The target pulse charging stage is the pulse charging stage corresponding to the stage data interval to which the second battery data belongs.

10. The battery charging method according to claim 7 or 9, characterized in that, The data range for the specified stage is the SOC threshold range and / or the voltage threshold range.

11. The battery charging method according to claim 1, characterized in that, The battery charging method further includes: The current temperature condition is determined based on the third battery data of the power battery; In response to the current temperature condition being a low-temperature condition, the power battery is controlled to heat up. In response to the current temperature condition being normal temperature, the current charge condition is determined based on the first battery data of the power battery.

12. The battery charging method according to claim 11, characterized in that, The third battery data includes the current temperature.

13. The battery charging method according to claim 12, characterized in that, The determination of the current temperature condition based on the third battery data of the power battery includes: In response to the current temperature being less than a first temperature threshold, the current temperature condition is determined to be a low-temperature condition.

14. The battery charging method according to claim 12, characterized in that, The determination of the current temperature condition based on the third battery data of the power battery includes: In response to the current temperature being greater than or equal to the first temperature threshold, the current temperature condition is determined to be a normal temperature condition.

15. The battery charging method according to claim 12, characterized in that, The control of the power battery temperature rise includes: The power battery is controlled to self-heat up by adopting the temperature rise control strategy corresponding to the current temperature.

16. The battery charging method according to claim 15, characterized in that, The method of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes: In response to the current temperature being less than a second temperature threshold, the power battery is controlled to self-heat up based on a self-heating strategy.

17. The battery charging method according to claim 15, characterized in that, The method of using a temperature control strategy corresponding to the current temperature to control the self-heating of the power battery includes: In response to the current temperature being greater than or equal to a second temperature threshold, the power battery is controlled to self-heat up based on a self-heating strategy, and the power battery is charged based on a second constant current charging strategy.

18. The battery charging method according to claim 17, characterized in that, The charging of the power battery based on the second constant current charging strategy includes: Based on the current temperature and current state of charge (SOC), determine the second constant current; and The power battery is charged based on the second constant current.

19. The battery charging method according to claim 18, characterized in that, The determination of the second constant current based on the current temperature and current SOC includes: Based on the current temperature, current SOC and constant current mapping data, the second constant current is determined.

20. The battery charging method according to any one of claims 1 to 19, characterized in that, The target charging current is less than the safe charging current, which is the charging current corresponding to the first battery data at the lithium plating boundary of the battery.

21. A controller comprising a memory, a processor, and computer instructions stored in the memory and executable on the processor, characterized in that, When the processor executes the computer instructions, it implements the battery charging method according to any one of claims 1 to 20.

22. A charging and discharging system, characterized in that, The charging and discharging system includes a charging and discharging circuit and the controller as described in claim 21; The charging and discharging circuit is used to connect the charging power supply and the power battery; and The controller is connected to the charging and discharging circuit and is used to control the operation of the charging and discharging circuit so that the charging power supply charges the power battery.

23. The charging and discharging system as described in claim 22, characterized in that, The charging and discharging circuit includes at least one bridge arm and at least one inductor (L1). Each bridge arm includes an upper bridge power transistor (T1) and a lower bridge power transistor (T2) connected in series. The connection node between the upper bridge power transistor (T1) and the lower bridge power transistor (T2) is connected to the first end of the inductor (L1). At least one of the upper bridge power transistors (T1) is used to connect to the positive terminal of the power battery; At least one of the lower bridge power transistors (T2) is used to connect to the negative terminal of the power battery; as well as At least one of the inductors (L1) has its second end used to connect to the inter-cell node of the power battery, wherein the inter-cell node is the node between two adjacent cells in the power battery.

24. The charging and discharging system as described in claim 17, characterized in that, The charging and discharging circuit also includes a capacitor (C1), the first end of which is used to connect to the positive terminal of the power battery, and the second end of which is used to connect to the negative terminal of the power battery.

25. A computer-readable storage medium storing computer instructions, characterized in that, When the computer instructions are executed by the processor, they implement the battery charging method according to any one of claims 1 to 20.

26. A vehicle, characterized in that, This includes the controller of claim 21, the charging / discharging system of any one of claims 22 to 24, or the computer-readable storage medium of claim 25.

Images