Battery lithium precipitation control method, device, equipment, medium and program product

Abstract

The application provides a battery charging lithium precipitation control method, device, equipment, medium and program product, and relates to the technical field of battery charging. The battery charging lithium precipitation control method can more specifically reduce the concentration polarization generated in the charging of the power battery at the end of high-rate charging by sending a first control instruction for indicating the output power control parameters of different lithium precipitation control stages to the charging pile when it is determined that the power battery meets the lithium precipitation control entry condition, and adopting the pulse discharge stage, the standing relaxation stage and the forward charging stage to correspondingly depolarize the power battery, thereby significantly improving the depolarization efficiency, effectively inhibiting the occurrence of negative electrode lithium precipitation, improving the safety and stability of the power battery in the charging process, prolonging the cycle service life of the power battery, and balancing the charging efficiency and energy utilization efficiency.

Description

Technical Field

[0001] This application relates to the field of battery charging technology, and in particular to a battery charging lithium plating control method, apparatus, equipment, medium and program product. Background Technology

[0002] With the rapid development of new energy vehicles, in order to improve the charging speed of power batteries and optimize the user charging experience, the charging rate of DC fast charging and ultra-fast charging for vehicles continues to increase.

[0003] During the final stages of charging, especially at high rates such as DC fast charging or DC ultra-fast charging, significant concentration polarization easily forms inside the battery, which can readily lead to lithium plating on the negative electrode. Lithium plating not only significantly reduces the cycle life and usable capacity of the battery, but also poses safety hazards such as internal short circuits and thermal runaway, severely restricting the safe application of high-rate fast charging technology and the battery's durability.

[0004] Therefore, there is an urgent need to provide a control method that can effectively suppress lithium plating during the charging process of power batteries. Summary of the Invention

[0005] This application provides a method, apparatus, device, medium, and program product for controlling lithium plating during battery charging, which is used to suppress or eliminate lithium plating during the charging process of power batteries and improve battery charging safety and cycle life.

[0006] In a first aspect, this application provides a battery charging lithium plating control method, comprising: determining whether the power battery meets the lithium plating control entry conditions during the charging process of the power battery connected to an external charging pile; if the power battery meets the lithium plating control entry conditions, sending a first control command to the charging pile, the first control command being used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages, the power control parameters being used to depolarize the power battery at the corresponding lithium plating control stage, the lithium plating control stage including a pulse discharge stage, a rest relaxation stage, and a forward charging stage.

[0007] In one possible implementation, determining whether the power battery meets the lithium plating control entry conditions includes: acquiring parameter information of the power battery, including the current state of charge (SOC) and the current cell temperature; and determining whether the power battery meets the lithium plating control entry conditions based on the current SOC and the current cell temperature.

[0008] In one possible implementation, determining whether the power battery meets the lithium plating control entry conditions based on the current SOC and the current cell temperature includes: determining whether the current SOC is greater than the SOC threshold and whether the current cell temperature is less than or equal to the temperature threshold; if the current SOC is greater than the SOC threshold and the current cell temperature is less than or equal to the temperature threshold, then the power battery meets the lithium plating control entry conditions; if the current SOC is less than or equal to the SOC threshold, or the current cell temperature is greater than the temperature threshold, then the power battery does not meet the lithium plating control entry conditions.

[0009] In one possible implementation, the battery charging lithium plating control method further includes: within a preset time period, determining whether the power battery meets the lithium plating control entry conditions based on the current SOC.

[0010] In one possible implementation, the parameter information also includes the current available cell capacity and historical lithium plating level. Before sending the first control command to the charging pile, the method further includes: calculating the pulse discharge current and pulse discharge duration based on the current available cell capacity, current SOC, current cell temperature and historical lithium plating level; and calculating the forward charging duration based on the current cell temperature and current SOC.

[0011] In one possible implementation, the power control parameters include pulse discharge power parameters, rest relaxation power parameters, and forward charging power parameters. The pulse discharge power parameters include pulse discharge current and pulse discharge duration. The rest relaxation power parameters include rest zero current. The forward charging power parameters include forward charging request current and forward charging duration. Depolarization of the power battery during the corresponding lithium plating control stage includes: pulse discharging the power battery using a pulse discharge current for the duration of the pulse discharge; in response to the end of the pulse discharge, using a rest zero current to allow the power battery to rest in an open circuit; and in response to the end of the open circuit rest, using a forward charging request current to perform forward charging of the power battery for the duration of the forward charging duration.

[0012] In one possible implementation, the method further includes: real-time acquisition of the battery voltage; real-time calculation of the polarization gradient of the battery based on the battery voltage; and termination of the open-circuit static setting of the battery in response to the polarization gradient being less than or equal to the polarization gradient threshold.

[0013] In one possible implementation, during the depolarization process of the corresponding lithium plating control stage of the power battery, the method further includes: obtaining the total depolarization time corresponding to the depolarization process; determining whether the total depolarization time is greater than or equal to the depolarization exit time; if the total depolarization time is greater than or equal to the depolarization exit time, then the power battery is determined to meet the lithium plating control exit condition, and a second control command is sent to the charging pile, the second control command being used to instruct the charging pile to output a positive charging request current to the power battery; if the total depolarization time is less than the depolarization exit time, then the power battery is determined not to meet the lithium plating control exit condition, and the depolarization steps of the corresponding lithium plating control stage of the power battery are repeated.

[0014] In one possible implementation, before sending the first control command to the charging pile, the method further includes: obtaining the average charging rate and average cell temperature of the power battery within a target charging duration, wherein the target charging duration is the time difference between the start time of the current charging of the power battery and the time when it enters the lithium plating control, and the lithium plating control time is the time when the power battery meets the lithium plating control entry conditions; and calculating the depolarization exit duration based on the average charging rate and average cell temperature.

[0015] In one possible implementation, during the depolarization process of pulse discharge of the power battery, the method further includes: distributing the electrical energy output by the power battery to the power-related devices according to a preset power distribution priority order; wherein the power-related devices include an electrical load, a first energy storage battery, and a second energy storage battery.

[0016] Secondly, this application provides a battery charging lithium plating control device, comprising:

[0017] The determination module is used to determine whether the power battery meets the lithium plating control entry conditions during the charging process of the power battery connected to the external charging pile.

[0018] The control module is used to send a first control command to the charging pile when the power battery meets the lithium plating control entry conditions. The first control command is used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages. The power control parameters are used to depolarize the power battery for the corresponding lithium plating control stage. The lithium plating control stages include pulse discharge stage, rest relaxation stage and forward charging stage.

[0019] In one possible implementation, the determining module is specifically used to: acquire parameter information of the power battery, including the current SOC and the current cell temperature; and determine whether the power battery meets the lithium plating control entry conditions based on the current SOC and the current cell temperature.

[0020] In one possible implementation, the determining module is further configured to: determine whether the current SOC is greater than the SOC threshold, and determine whether the current cell temperature is less than or equal to the temperature threshold; if the current SOC is greater than the SOC threshold and the current cell temperature is less than or equal to the temperature threshold, then the power battery is determined to meet the lithium plating control entry conditions; if the current SOC is less than or equal to the SOC threshold, or the current cell temperature is greater than the temperature threshold, then the power battery is determined not to meet the lithium plating control entry conditions.

[0021] In one possible implementation, the determining module is further configured to: within a preset time period, determine whether the power battery meets the lithium plating control entry conditions based on the current SOC.

[0022] In one possible implementation, the parameter information also includes the current available cell capacity and historical lithium plating level. Before sending the first control command to the charging pile, the battery charging lithium plating control device also includes a calculation module (not shown), which is used to: calculate the pulse discharge current and pulse discharge duration based on the current available cell capacity, current SOC, current cell temperature and historical lithium plating level; and calculate the forward charging duration based on the current cell temperature and current SOC.

[0023] In one possible implementation, the power control parameters include pulse discharge power parameters, rest relaxation power parameters, and forward charging power parameters. The pulse discharge power parameters include pulse discharge current and pulse discharge duration, the rest relaxation power parameters include rest zero current, and the forward charging power parameters include forward charging request current and forward charging duration. Specifically, the control module is used to: pulse discharge the power battery using the pulse discharge current within the pulse discharge duration; in response to the end of the pulse discharge, open-circuit rest the power battery using the rest zero current; and in response to the end of the open-circuit rest, forward charge the power battery using the forward charging request current within the forward charging duration.

[0024] In one possible implementation, during the open-circuit resting process of the power battery, the control module is also used to: collect the battery voltage of the power battery in real time; calculate the polarization gradient of the power battery in real time based on the battery voltage; and terminate the open-circuit resting of the power battery in response to the polarization gradient being less than or equal to the polarization gradient threshold.

[0025] In one possible implementation, the determining module is further configured to: obtain the total depolarization time corresponding to the depolarization process; determine whether the total depolarization time is greater than or equal to the depolarization exit time; if the total depolarization time is greater than or equal to the depolarization exit time, determine that the power battery meets the lithium plating control exit condition, and send a second control command to the charging pile, the second control command being used to instruct the charging pile to output a positive charging request current to the power battery; if the total depolarization time is less than the depolarization exit time, determine that the power battery does not meet the lithium plating control exit condition, and repeat the depolarization steps of the corresponding lithium plating control stage for the power battery.

[0026] In one possible implementation, before sending the first control command to the charging pile, the calculation module is further configured to: obtain the average charging rate and average cell temperature of the power battery within the target charging duration, wherein the target charging duration is the time difference between the start time of the current charging of the power battery and the time of entering the lithium plating control, and the lithium plating control time is the time when the power battery meets the conditions for entering the lithium plating control; and calculate the depolarization exit duration based on the average charging rate and average cell temperature.

[0027] In one possible implementation, during the depolarization process of pulse discharge of the power battery, the battery charging lithium plating control device further includes an energy distribution module (not shown), which is used to: distribute the power battery output to the power-related devices according to a preset energy distribution priority order; wherein the power-related devices include an electrical load, a first energy storage battery, and a second energy storage battery.

[0028] Thirdly, this application provides an electronic device, including: a memory and a processor;

[0029] The memory stores the instructions that the computer executes;

[0030] The processor executes computer execution instructions stored in memory, causing the processor to perform the battery charging lithium plating control method provided in the first aspect above.

[0031] Fourthly, embodiments of this application provide a battery system, including: a controller and a power battery;

[0032] The controller is used to execute the battery charging lithium plating control method provided in the first aspect above during the charging process of the power battery connected to an external charging pile.

[0033] In one possible implementation, the battery system also includes: electrical-related devices;

[0034] Electrically-related devices are connected to the power battery and are used to receive electrical energy output from the power battery during the depolarization process of pulse discharge.

[0035] Fifthly, embodiments of this application provide an electrical device including the battery system provided in the fourth aspect above.

[0036] In one possible implementation, the electrical equipment includes vehicles.

[0037] In a sixth aspect, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the battery charging lithium plating control method provided in the first aspect above.

[0038] In a seventh aspect, this application provides a computer program product, comprising: a computer program that, when executed by a processor, implements the battery charging lithium plating control method provided in the first aspect above.

[0039] The battery charging lithium plating control method, apparatus, equipment, medium, and program products provided in this application determine whether the power battery meets the lithium plating control entry conditions during the charging process of the power battery connected to an external charging pile. When the power battery meets the lithium plating control entry conditions, a first control command is sent to the charging pile. The first control command is used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages. The power control parameters are used to depolarize the power battery according to the corresponding lithium plating control stage. The lithium plating control stages include a pulse discharge stage, a rest relaxation stage, and a forward charging stage. This application, during the charging process of a power battery connected to an external charging pile, sends a first control command to the charging pile when it is determined that the power battery meets the conditions for entering lithium plating control. This command indicates the output power control parameters for different lithium plating control stages. The power battery is depolarized accordingly using pulse discharge stage, rest relaxation stage, and forward charging stage. This can more effectively reduce the concentration polarization generated during power battery charging at the end of high-rate charging, thereby significantly improving depolarization efficiency, effectively suppressing the occurrence of negative electrode lithium plating, improving the safety and stability of the power battery during charging, extending the cycle life of the power battery, and simultaneously taking into account charging efficiency and energy utilization efficiency. Attached Figure Description

[0040] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0041] Figure 1 This is one of the flowcharts illustrating the battery charging lithium plating control method provided in the embodiments of this application;

[0042] Figure 2 A second schematic flowchart of the battery charging lithium plating control method provided in the embodiments of this application;

[0043] Figure 3The third schematic flowchart of the battery charging lithium plating control method provided in the embodiments of this application;

[0044] Figure 4 This is a schematic diagram of the current timing for the depolarization process provided in an embodiment of this application;

[0045] Figure 5 This is a schematic diagram of the structure of the power battery and power-related devices provided in the embodiments of this application;

[0046] Figure 6 This is a schematic diagram of the battery charging lithium plating control device provided in the embodiments of this application;

[0047] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application.

[0048] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation

[0049] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0050] Power battery charging control technology is widely used in DC fast charging and ultra-fast charging scenarios for new energy vehicles, especially in charging safety management under high charge conditions. When the vehicle is charged by an external charging station, the on-board battery management system usually works with the charging station to monitor and adjust the charging process of the power battery to balance charging efficiency, battery cycle life, and safety.

[0051] During the final stages of charging, especially at high rates during DC fast or ultra-fast charging, the lithium-ion concentration near the surface of the graphite particles in the negative electrode drops sharply due to solid-phase diffusion kinetics. This leads to a continuous increase in concentration polarization on the negative electrode side, causing the polarization overpotential to accumulate. When the polarization overpotential exceeds the thermodynamic equilibrium threshold, the negative electrode potential drops below 0V, inducing lithium plating. Lithium plating not only accelerates battery capacity decay and shortens cycle life but also poses serious safety hazards such as thermal runaway and internal short circuits due to lithium dendrite growth piercing the separator or undergoing violent side reactions with the electrolyte.

[0052] In related technologies, to alleviate the lithium plating problem at the end of the charging process of power batteries, a short discharge pulse is usually applied to reduce polarization. However, in this method, the discharge pulse can only partially alleviate concentration polarization and cannot completely eliminate lithium plating, resulting in poor lithium plating suppression.

[0053] Based on the technical problems existing in related technologies, the embodiments of this application, during the charging process of the power battery connected to an external charging pile, send control commands to the charging pile to indicate the output power control parameters for different lithium plating control stages when it is determined that the power battery meets the lithium plating control entry conditions. The power battery is depolarized accordingly using pulse discharge stage, static relaxation stage and forward charging stage. This can more effectively reduce the concentration polarization generated during power battery charging at the end of high-rate charging, thereby significantly improving depolarization efficiency, effectively suppressing the occurrence of negative electrode lithium plating, improving the safety and stability of the power battery during charging, extending the cycle life of the power battery, and taking into account both charging efficiency and energy utilization efficiency.

[0054] The application scenarios of the embodiments of this application will be described below first.

[0055] The lithium plating control method for battery charging provided in this application can be applied to high-rate charging scenarios for power batteries in new energy vehicles, especially during DC fast charging or ultra-fast charging. Specifically, when the vehicle is charging at an external charging station, the Battery Management System (BMS) works in conjunction with the charging station to suppress lithium plating caused by concentration polarization in the power battery at the end of charging by dynamically controlling pulse discharge-restoration-forward charging.

[0056] The following describes in detail the specific implementation of the battery charging lithium plating control method provided in this application embodiment, taking BMS as the execution subject and combining specific embodiments.

[0057] Figure 1 This is one of the flowcharts illustrating a battery charging lithium plating control method provided in an embodiment of this application. Figure 1 As shown, a specific implementation of this battery charging lithium plating control method may include the following steps:

[0058] S101, during the charging process of the power battery connected to an external charging pile, determines whether the power battery meets the lithium plating control entry conditions.

[0059] The charging process of the power battery connected to an external charging pile refers to the process in which the battery management system continuously receives power battery operation data and interacts with the charging pile to exchange charging control information after the vehicle establishes a physical and communication connection with the external charging pile via the DC charging interface.

[0060] For example, the charging station can be a DC charging station.

[0061] For example, the lithium plating control entry condition is used to determine whether the current power battery has entered the charging range where depolarization control needs to be performed.

[0062] For example, in one possible implementation, during the charging process of the power battery connected to an external charging pile, the current SOC of the power battery is acquired in real time, and it is determined whether the current SOC is greater than a SOC threshold within a preset time period. If the current SOC is greater than the SOC threshold within the preset time period, it is determined that the power battery meets the lithium plating control entry condition; if there is a situation where the current SOC is less than or equal to the SOC threshold within the preset time period, it is determined that the power battery does not meet the lithium plating control entry condition. The preset time period can be 300ms. This application embodiment does not limit the specific value of the preset time period; it can be determined according to the actual application requirements.

[0063] For example, in another possible implementation, during the charging process of the power battery connected to an external charging pile, the current SOC of the power battery is acquired in real time, and it is determined whether the current SOC is greater than the SOC threshold. If the current SOC is greater than the SOC threshold, it is determined that the power battery meets the lithium plating control entry condition; if the current SOC is less than or equal to the SOC threshold, it is determined that the power battery does not meet the lithium plating control entry condition.

[0064] It is understandable that in the above implementation method, the preset duration can be the anti-jitter delay. By configuring the anti-jitter delay, interference signals caused by sampling glitches, instantaneous current fluctuations, voltage jumps and other disturbances can be filtered out, avoiding false triggering of lithium plating control and effectively improving the accuracy of lithium plating control entry condition determination.

[0065] Optionally, if the power battery does not meet the lithium plating control entry conditions, the current conventional charging control logic is maintained, and the power battery is continuously charged normally.

[0066] Optionally, in one possible implementation, when it is determined that the power battery meets the lithium plating control entry conditions, a lithium plating control mode entry flag is generated. This lithium plating control mode entry flag is used to trigger the generation and sending process of control commands corresponding to each subsequent lithium plating control stage, and to start the power battery depolarization regulation.

[0067] S102, if the power battery meets the lithium plating control entry conditions, a first control command is sent to the charging pile. The first control command is used to indicate the power control parameters output by the charging pile to the power battery during different lithium plating control stages. The power control parameters are used to depolarize the power battery for the corresponding lithium plating control stage. The lithium plating control stages include pulse discharge stage, rest relaxation stage and forward charging stage.

[0068] The first control instruction is a phased control message or control frame sent by the BMS to the charging pile, including but not limited to the lithium plating control mode entry identifier, the execution order of each lithium plating control stage, and the power control parameters of the corresponding lithium plating control stage.

[0069] The power control parameters serve as the basis for the charging pile's output power during each lithium plating control stage. These stages define different action periods within the depolarization process. Specifically, the pulse discharge stage releases accumulated polarization in the battery, rapidly reducing concentration polarization; the resting relaxation stage provides sufficient diffusion time for lithium ions within the battery, enabling cell rebalancing; and the forward charging stage resumes energy replenishment after sufficient polarization decay, ensuring overall charging efficiency. This embodiment utilizes a three-stage time-sharing coordinated control to complete a full battery depolarization regulation process, effectively suppressing lithium plating at the end of battery charging.

[0070] For example, the first control instruction may include power control parameters corresponding to all lithium plating control stages; the first control instruction may also include power control parameters corresponding to a single lithium plating control stage.

[0071] For example, in one possible implementation, when the power battery meets the conditions for entering lithium plating control, the BMS generates power control parameters corresponding to each lithium plating control stage applicable to the current power battery state, and encapsulates all power control parameters into a first control command and sends it to the charging pile. For the pulse discharge stage, the rest relaxation stage, and the forward charging stage, the charging pile can switch between the corresponding lithium plating control stages and control the power output according to the power control parameters in the first control command. The communication method between the BMS and the charging pile can use the existing charging communication link between the vehicle and the charging pile, such as data interaction based on a Controller Area Network (CAN) bus or a higher-level charging protocol. This application embodiment does not limit this; the specific method can be determined according to actual application requirements.

[0072] For example, in another possible implementation, when the power battery meets the lithium plating control entry conditions, the BMS generates power control parameters corresponding to each lithium plating control stage applicable to the current power battery state based on the current power battery state. First, the power control parameters corresponding to the pulse discharge stage are encapsulated as a first control command and sent to the charging pile. The charging pile performs pulse discharge on the power battery based on the power control parameters corresponding to the pulse discharge stage. Then, when the duration of the pulse discharge is detected to reach the pulse discharge duration included in the power control parameters, the power control parameters corresponding to the resting relaxation stage are encapsulated as a first control command and sent to the charging pile. The charging pile performs open-circuit resting on the power battery based on the power control parameters corresponding to the resting relaxation stage. Finally, when the open-circuit resting is detected to end, the power control parameters corresponding to the forward charging stage are encapsulated as a first control command and sent to the charging pile. The charging pile performs forward charging on the power battery based on the power control parameters corresponding to the forward charging stage.

[0073] It is understood that the embodiments of this application do not rely on a single short-term pulse discharge to improve the polarization state of the power battery. Instead, they complete the full depolarization control process of the power battery through a three-stage coordinated combination of pulse discharge, rest relaxation, and forward charging. Specifically, the pulse discharge stage can quickly release the concentration polarization accumulated on the surface of the power battery electrodes, initially weakening the polarization overpotential; the rest relaxation stage, under zero-current rest conditions, provides sufficient time for the lithium-ion concentration gradient inside the power battery to dissipate and the reaction state of the electrode interface to reach equilibrium, achieving sufficient attenuation of polarization; the forward charging stage continues the charging process, restoring battery energy replenishment after polarization elimination, effectively avoiding the problem of lithium plating control process and normal charging operation being mutually disconnected, affecting charging efficiency.

[0074] Based on the aforementioned phased collaborative control logic, this embodiment of the application drives the charging pile to dynamically switch between charging, pulse discharge, rest relaxation, and forward charging modes in an orderly manner during a single external charging process via a first control command. Furthermore, the power control parameters for each stage are adaptively matched according to the real-time state of the power battery. Compared to traditional single-pulse control schemes, this embodiment of the application can precisely intervene in the concentration polarization and reversible lithium plating trend already formed during the charging process, effectively suppressing negative electrode lithium plating from its root cause. While ensuring fast charging efficiency, it significantly optimizes battery charging safety and cycle life.

[0075] In this step, after identifying the timing for lithium plating control to enter, the BMS encapsulates the power control parameters corresponding to the pulse discharge stage, the rest relaxation stage, and the forward charging stage into a first control command and sends it to the charging pile. The charging pile then executes depolarization control in the order of the stages, so that the depolarization action is triggered during the actual charging process required by the power battery. Through the continuous coordination of the pulse discharge stage, the rest relaxation stage, and the forward charging stage, the polarization state and the risk of reversible lithium plating are handled, while maintaining the continuity of the external charging process.

[0076] In this embodiment of the application, during the charging process of the power battery connected to an external charging pile, when it is determined that the power battery meets the conditions for entering the lithium plating control, a first control command is sent to the charging pile to indicate the output power control parameters for different lithium plating control stages. The power battery is depolarized accordingly using pulse discharge stage, rest relaxation stage and forward charging stage. This can more effectively reduce the concentration polarization generated during the charging of the power battery at the end of high-rate charging, thereby significantly improving the depolarization efficiency, effectively suppressing the occurrence of negative electrode lithium plating, improving the safety and stability of the power battery during charging, extending the cycle life of the power battery, and taking into account both charging efficiency and energy utilization efficiency.

[0077] The following is combined with Figure 2 A detailed explanation is provided of a specific implementation method for determining whether the power battery meets the lithium plating control entry conditions in step S101.

[0078] Figure 2 This is a second schematic flowchart illustrating the battery charging lithium plating control method provided in this application embodiment. Figure 2 As shown, a specific implementation of the battery charging lithium plating control method for determining whether the power battery meets the lithium plating control entry conditions may include the following steps:

[0079] S201, obtain the parameter information of the power battery, including the current SOC and the current cell temperature.

[0080] For example, parameter information can be acquired in real time by the acquisition unit corresponding to the power battery. This acquisition unit may include, but is not limited to, a voltage sampling circuit, a temperature sensor, and a data acquisition module connected to the BMS. For example, the temperature sensor may be located on the surface of the power battery cell or in a nearby position inside the cell to obtain a temperature value that reflects the thermal state of the cell.

[0081] For example, the current SOC can be calculated using a fusion algorithm combining open-circuit voltage lookup and ampere-hour integration. Specifically, before charging the power battery, the power battery is kept in an open-circuit resting state until the internal polarization is fully dissipated. The voltage at the battery terminals at this time is collected as the effective open-circuit voltage (OCV). The mapping curve / data table between the pre-calibrated open-circuit voltage and SOC is retrieved. Based on the collected effective open-circuit voltage, the table is looked up to determine the power battery's resting calibration SOC. When the battery enters the charging and discharging state and there is charging and discharging current, the calibration SOC obtained from the resting table is used as the initial SOC. The accumulated charge and discharge capacity is calculated in real time using the ampere-hour integration method, and the SOC value is continuously updated to obtain the real-time current SOC of the power battery.

[0082] S202, based on the current SOC and current cell temperature, determines whether the power battery meets the conditions for lithium plating control.

[0083] Understandably, on the one hand, when a power battery is charged to a high SOC range, the number of active sites on the negative electrode available for lithium ion insertion is significantly reduced. If the power battery is continuously charged with a large current, a large number of lithium ions migrate rapidly to the negative electrode. The lithium ion insertion rate cannot match the lithium ion supply rate, resulting in lithium ion accumulation on the negative electrode surface, causing significant concentration polarization, which easily induces lithium metal deposition on the negative electrode. On the other hand, under low-temperature conditions, both the lithium ion solid-phase diffusion rate and the electrolyte ion migration rate are significantly reduced. Under the same charging current and the same SOC state, low temperature significantly increases the polarization overpotential, significantly increasing the risk of lithium deposition. In contrast, ion diffusion is more complete in high-temperature environments, resulting in lower battery polarization and eliminating the need for depolarization control. Therefore, this application embodiment combines real-time SOC and real-time cell temperature to comprehensively determine whether the power battery meets the lithium deposition control entry conditions, accurately identifying high lithium deposition risk ranges and effectively improving the accuracy of lithium deposition control entry condition determination.

[0084] Optionally, one possible implementation is to determine whether the current SOC is greater than the SOC threshold and whether the current cell temperature is less than or equal to the temperature threshold; if the current SOC is greater than the SOC threshold and the current cell temperature is less than or equal to the temperature threshold, then the power battery meets the lithium plating control entry conditions; if the current SOC is less than or equal to the SOC threshold, or the current cell temperature is greater than the temperature threshold, then the power battery does not meet the lithium plating control entry conditions.

[0085] Among them, the SOC threshold is used to characterize the state of charge threshold required for the power battery to enter the lithium plating control; the temperature threshold is used to characterize the upper limit of the cell temperature allowed when the power battery enters the lithium plating control.

[0086] For example, the SOC threshold can be obtained through bench testing of power batteries.

[0087] For example, when the power battery uses a nickel-cobalt-manganese ternary cathode cell, the SOC threshold can be 90%, and when the power battery uses a lithium iron phosphate cathode cell, the SOC threshold can be 95%. This application does not limit the specific value of the SOC threshold; it can be flexibly calibrated according to actual application requirements such as the battery system and charging conditions.

[0088] For example, the temperature threshold can be 10°C. This application does not limit the specific value of the temperature threshold; it can be determined according to actual application requirements.

[0089] For example, in one possible implementation, the SOC threshold and temperature threshold can be stored in the calibration parameter area inside the controller and can be preset and adjusted according to the battery system, battery aging state or current charging rate.

[0090] It is understood that, by using both the SOC threshold and the temperature threshold as the entry conditions for lithium plating control, the controller can initiate subsequent lithium plating control only when the power battery is at a high SOC and the cell temperature meets the requirements. This makes the lithium plating control entry judgment match the risk state at the end of charging and provides a clear triggering basis for subsequent depolarization control, thereby reducing control intervention under unsuitable conditions and making the start and stop of lithium plating control more stable.

[0091] Optionally, in another possible implementation, within a preset time period, it is determined whether the current SOC is greater than the SOC threshold and whether the current cell temperature is less than or equal to the temperature threshold. If, within the preset time period, the current SOC remains greater than the SOC threshold and the current cell temperature remains less than or equal to the temperature threshold, then the power battery is determined to meet the lithium plating control entry conditions. If, within the preset time period, there is a situation where the current SOC is less than or equal to the SOC threshold, or there is a situation where the current cell temperature is greater than the temperature threshold, then the power battery is determined not to meet the lithium plating control entry conditions. The preset time period is similar to the above and can be an anti-shake delay.

[0092] In this embodiment, by synchronously acquiring the current SOC and current cell temperature of the power battery and making a joint judgment based on the two, the triggering of lithium plating control is matched with the current charge state and thermal state of the power battery. This ensures that subsequent control commands are only triggered when the risk judgment conditions are met, making the timing of entering lithium plating control more in line with the risk changes at the end of charging, reducing unnecessary control intervention, and providing a stable judgment basis for subsequent depolarization control.

[0093] Alternatively, in one possible implementation, within a preset time period, it is determined whether the power battery meets the lithium plating control entry conditions based on the current SOC.

[0094] For example, within a preset time period, it is determined whether the current SOC is greater than the SOC threshold. If the current SOC is always greater than the SOC threshold within the preset time period, it is determined that the power battery meets the lithium plating control entry conditions. If, within the preset time period, there is a situation where the current SOC is less than or equal to the SOC threshold, it is determined that the power battery does not meet the lithium plating control entry conditions. The preset time period is similar to that described above and will not be repeated here.

[0095] Optionally, the parameter information obtained in the embodiments of this application may also include the current available cell capacity and historical lithium plating level.

[0096] For example, the historical lithium plating level is a characterization of the degree of lithium plating in the battery, obtained by evaluating it through a lithium plating diagnostic algorithm after the previous charging cycle adjacent to the current charging cycle. The lithium plating diagnostic algorithm can be a built-in state assessment algorithm of the BMS, and its specific implementation can be as follows: After the end of a single charging cycle of the power battery, the BMS retrieves and summarizes multi-dimensional operating parameters such as the SOC change trajectory, cell temperature range distribution, charging rate time series data, peak polarization overpotential and its duration, etc., throughout the entire charging process; through a preset risk factor weighting model, it weights and fuses the low-temperature high SOC charging time, high-current polarization accumulation degree, and voltage abnormal offset to quantify the degree of reversible lithium plating accumulation and irreversible lithium plating damage of the power battery, respectively; the comprehensive lithium plating risk value obtained by the fusion calculation is compared with pre-calibrated multi-level thresholds, and a graded output of quantitative lithium plating levels such as no lithium plating, mild reversible lithium plating, moderate lithium plating, and severe lithium plating is generated and stored as the historical lithium plating level for the current charging cycle, used for pre-charge risk assessment.

[0097] For example, the currently available cell capacity can be the cell's rated capacity.

[0098] Optionally, before sending the first control command to the charging pile, the battery charging lithium plating control method provided in this application embodiment further includes: calculating the pulse discharge current and pulse discharge duration based on the current available cell capacity, current SOC, current cell temperature and historical lithium plating level; and calculating the forward charging duration based on the current cell temperature and current SOC.

[0099] Among them, the pulse discharge current is the discharge intensity parameter used in the pulse discharge phase, the pulse discharge duration is the duration parameter of the continuous action of the discharge intensity, and the forward charging duration is the duration parameter maintained when resuming charging after the rest relaxation ends.

[0100] For example, one possible implementation for calculating the pulse discharge current and pulse discharge duration based on the current available cell capacity, current SOC, current cell temperature, and historical lithium plating level is as follows: First, calculate the baseline pulse discharge current and baseline pulse discharge duration using the current available cell capacity; configure correction coefficients corresponding to the current cell temperature, current SOC, and historical lithium plating level respectively; perform joint scaling correction on the baseline pulse discharge current and baseline pulse discharge duration based on the correction coefficients; after correction, apply upper and lower boundary constraints to the corrected pulse discharge current and corrected pulse discharge duration using preset current and duration safety thresholds to obtain the pulse discharge current and pulse discharge duration adapted to the current state of the power battery. The lower the current cell temperature, the higher the current SOC, and the higher the historical lithium plating level, the larger the corresponding correction coefficient value, and the pulse discharge current and pulse discharge duration increase simultaneously, achieving adaptive intervention for polarization and reversible lithium plating risks.

[0101] For example, one possible implementation for calculating the reference pulse discharge current and reference pulse discharge duration based on the current available cell capacity is as follows: Based on the reference discharge rate pre-calibrated on the battery test bench, the current available cell capacity is multiplied by the reference discharge rate to obtain the reference pulse discharge current; simultaneously, the available cell capacity and reference duration calibration curves are matched to query the reference pulse discharge duration corresponding to the current available cell capacity. The larger the current available cell capacity, the greater the corresponding reference pulse discharge current and reference pulse discharge duration; the reference discharge rate, available cell capacity, and reference duration calibration curves can be calibrated based on tests of different battery systems such as nickel-cobalt-manganese ternary and lithium iron phosphate, and this application embodiment does not limit this.

[0102] It should be noted that the above-mentioned multi-parameter coupling adjustment logic can simultaneously improve the pulse discharge intensity and duration under high lithium plating risk conditions, and automatically reduce the pulse output under normal low-risk conditions. While suppressing concentration polarization and reversible lithium plating tendency, it ensures charging efficiency. Each correction coefficient and duration safety threshold can be determined through bench tests of different battery systems such as nickel-cobalt-manganese ternary and lithium iron phosphate. This application does not limit this.

[0103] For example, one possible implementation for calculating the forward charging time based on the current cell temperature and current SOC is as follows: A two-dimensional mapping relationship between SOC, cell temperature, and forward charging time can be established in advance through battery bench testing calibration. This two-dimensional mapping relationship can be stored as a two-dimensional lookup table, a piecewise linear function, or a polynomial fitting function. During runtime, the current SOC and current cell temperature are input into the two-dimensional mapping relationship, and the forward charging time is obtained by querying and solving. Specifically, when the power battery is in the high SOC range, the negative electrode has insufficient lithium intercalation sites, so the corresponding forward charging time is set to a shorter value to avoid concentration polarization accumulation during prolonged high-current charging. Under low-temperature conditions, the ion diffusion rate is low and the risk of lithium plating is higher, so a longer forward charging duration is matched to fully complete depolarization protection. Simultaneously, maximum and minimum limits for the forward charging time are set to prevent insufficient protection due to excessively short duration or reduced charging efficiency due to excessively long duration. The above two-dimensional mapping relationship and duration limits can be adjusted according to different cell systems such as nickel-cobalt-manganese ternary and lithium iron phosphate, and this application embodiment does not limit this.

[0104] In this embodiment, by introducing the current available cell capacity and historical lithium plating level, and completing the calculation of pulse discharge current, pulse discharge duration and forward charging duration before sending the first control command, the power control parameters can correspond to the power battery capacity and the previous lithium plating state. The depolarization control performed by the charging pile has a higher consistency with the current state of the power battery, thereby improving the adaptation accuracy of the lithium plating control parameters.

[0105] Optionally, the power control parameters include pulse discharge power parameters, rest relaxation power parameters, and forward charging power parameters. The pulse discharge power parameters include pulse discharge current and pulse discharge duration, the rest relaxation power parameters include rest zero current, and the forward charging power parameters include forward charging request current and forward charging duration.

[0106] The calculation methods for pulse discharge current, pulse discharge duration, and forward charging duration are similar to those described above, and will not be repeated here.

[0107] Optionally, in one possible implementation, the depolarization of the power battery during the corresponding lithium plating control stage includes: using a pulse discharge current to pulse discharge the power battery during the pulse discharge duration; in response to the end of the pulse discharge, using a zero-current resting state to open-circuit rest the power battery; and in response to the end of the open-circuit resting state, using a forward charging request current to forward charge the power battery during the forward charging duration.

[0108] Among them, open-circuit static setting refers to the process of static setting of the power battery under zero current conditions after the pulse discharge ends.

[0109] For example, in one possible implementation, during the pulse discharge phase, the charging pile outputs a pulse discharge current during the pulse discharge duration, causing the power battery to briefly release power in reverse. After the pulse discharge ends, the charging pile switches the output current to a static zero current, placing the power battery in an open-circuit static state. During the open-circuit static state, the battery voltage is simultaneously collected, and the polarization gradient is calculated. The open-circuit static state ends when the polarization gradient reaches the polarization gradient threshold. After the open-circuit static state ends, the charging pile resumes output current according to the forward charging request and continues to act during the forward charging duration, thereby completing the charging recovery after depolarization. The above control quantities can be executed by the charging pile in response to control commands issued by the BMS.

[0110] It is understood that in the lithium plating control method provided in the embodiments of this application, by switching between pulse discharge, open circuit rest and forward charging in sequence, the power battery enters a relaxation recovery state after short-term depolarization, and then resumes charging input, so that the power switching in the lithium plating control stage matches the battery polarization decay process.

[0111] Optionally, during the open-circuit resting process of the power battery, in one possible implementation, the battery charging lithium plating control method provided in this application embodiment further includes: real-time acquisition of the battery voltage of the power battery; real-time calculation of the polarization gradient of the power battery based on the battery voltage; and termination of the open-circuit resting of the power battery in response to the polarization gradient being less than or equal to the polarization gradient threshold.

[0112] Among them, the battery voltage is the power battery voltage collected in real time during the open-circuit resting process; the polarization gradient is calculated in real time based on the battery voltage and is used to characterize the polarization degree of the power battery; the polarization gradient threshold is the threshold for judging whether the open-circuit resting has ended.

[0113] For example, in one possible implementation of calculating the polarization gradient of a power battery in real time based on the battery voltage, the instantaneous rate of change of the battery voltage relative to time is calculated in real time, and this instantaneous rate of change is used as the polarization gradient.

[0114] For example, the polarization gradient can be expressed by the following formula:

[0115]

[0116] in, This represents the polarization gradient, and v represents the battery voltage. This represents the instantaneous rate of change of battery voltage relative to time.

[0117] The embodiments of this application do not limit the specific value of the polarization gradient threshold; it can be determined according to the actual application requirements.

[0118] It is understandable that when the pulse discharge stage, the rest relaxation stage, and the forward charging stage are considered as a lithium plating control cycle, the open-circuit rest duration corresponding to the rest relaxation stage may be the same or different in different lithium plating control cycles.

[0119] For example, in one possible implementation, when the polarization gradient calculated in real time is less than or equal to the polarization gradient threshold, the BMS generates an open-circuit resting end signal and switches the charging state to the subsequent forward charging control state.

[0120] In this embodiment, by matching the termination timing of open-circuit rest with the degree of polarization recovery, the open-circuit rest control can be terminated promptly after the depolarization requirement is met, and the control result is output to the subsequent charging stage. Since the end of open-circuit rest is determined in real time based on battery voltage characteristics, the system can complete dynamic control without relying on a fixed duration, thereby improving the adaptability and consistency of open-circuit rest control and enhancing the lithium plating suppression effect.

[0121] Optionally, during the depolarization process of the corresponding lithium plating control stage of the power battery, the battery charging lithium plating control method provided in this application embodiment further includes determining whether the power battery meets the lithium plating control exit conditions. The following is in conjunction with... Figure 3 A detailed explanation is provided on a specific implementation method for determining whether a power battery meets the lithium plating control exit conditions.

[0122] Figure 3 This is the third schematic flowchart illustrating the battery charging lithium plating control method provided in this application embodiment. Figure 3 As shown, a specific implementation of the battery charging lithium plating control method for determining whether the power battery meets the lithium plating control exit condition may include the following steps:

[0123] S301, obtain the total depolarization time corresponding to the depolarization process.

[0124] The total depolarization duration refers to the total duration of depolarization control experienced by the power battery during the corresponding lithium plating control stage. It can be obtained by the on-board battery management system by adding the time from the start time of the stage to the current time, and is used as the basis for determining whether to exit lithium plating control.

[0125] For example, in one possible implementation, the BMS continuously times the depolarization process during the corresponding lithium plating control phase and stores the start time, end time, and intermediate cumulative duration of this depolarization in the control cache to form the total depolarization duration.

[0126] S302, determine whether the total depolarization duration is greater than or equal to the depolarization exit duration.

[0127] The depolarization exit duration can be a pre-set time threshold or a time threshold generated by the control strategy, used to characterize the maximum duration that depolarization control is allowed to continue.

[0128] Optionally, in one possible implementation, the depolarization exit time can be calculated as follows: before sending the first control command to the charging pile, the average charging rate and average cell temperature of the power battery within the target charging time are obtained. The target charging time is the time difference between the start time of the current charging of the power battery and the time when it enters the lithium plating control, and the lithium plating control time is the time when the power battery meets the lithium plating control entry condition; the depolarization exit time is calculated based on the average charging rate and average cell temperature.

[0129] The target charging duration is used to characterize the charging process of the power battery from the start of this charging to the time when it enters the lithium plating control stage, and its value can be calculated from the timestamp difference.

[0130] Among them, the average charge rate is used to characterize the average charge intensity within the target charging time; the average cell temperature is used to characterize the average level of the cell thermal state within the target charging time.

[0131] For example, in one possible implementation, in response to the start of charging of the power battery, the BMS continuously collects charging current, cell voltage, and cell temperature signals in real time. When it is determined that the power battery meets the conditions for lithium plating control, the BMS calculates the charging rate based on the charging current collected within the target charging time and the rated capacity of the power battery, and calculates the average of the instantaneous charging rate at each sampling time to obtain the average charging rate of the current charging condition; simultaneously, it performs integral calculation or cumulative averaging on the cell temperature data collected within the target charging time to obtain the corresponding average cell temperature; based on the mapping relationship between the average charging rate, average cell temperature, and depolarization exit time pre-calibrated by the BMS, it queries and solves the mapping relationship according to the real-time calculated average charging rate and average cell temperature to finally obtain the depolarization exit time corresponding to this lithium plating control. This mapping relationship can be configured as a two-dimensional lookup table, a piecewise linear function, or a polynomial fitting function.

[0132] Understandably, by calculating the depolarization exit time based on the average charging rate and average cell temperature, the depolarization exit time is no longer set solely based on fixed parameters, but is determined by combining the average charging rate and average cell temperature within the target charging time. This ensures that the exit timing of depolarization control is consistent with the actual charging state of the power battery, improves the adaptability of lithium plating control parameters, and enhances the control accuracy of the subsequent charging process.

[0133] For example, in one possible implementation, it is determined whether the total depolarization duration is greater than or equal to the depolarization exit duration. If the total depolarization duration is greater than or equal to the depolarization exit duration, then step S303 is executed; if the total depolarization duration is less than the depolarization exit duration, then step S304 is executed.

[0134] S303, determine that the power battery meets the lithium plating control exit condition, and send a second control command to the charging pile. The second control command is used to instruct the charging pile to output a positive charging request current to the power battery.

[0135] Among them, the lithium plating control exit condition refers to the determination state of ending the current lithium plating control and resuming normal charging request.

[0136] For example, the second control command is used to switch the charging pile to the forward charging output mode and output a forward charging request current that matches the current charging needs of the power battery.

[0137] For example, in one possible implementation, when it is determined that the power battery meets the lithium plating control exit condition, the BMS generates a second control command and sends the second control command to the charging pile through the communication interface. After receiving the second control command, the charging pile ends the depolarization-related output and then outputs a positive charging request current to the power battery according to the normal charging protocol.

[0138] S304, determine that the power battery does not meet the lithium plating control exit conditions, and repeat the depolarization steps of the corresponding lithium plating control stage for the power battery.

[0139] For example, in one possible implementation, when it is determined that the power battery does not meet the lithium plating control exit conditions, the charging pile, based on the power control parameters indicated by the first control command, uses a pulse discharge current to pulse discharge the power battery within the pulse discharge duration; and in response to the end of the pulse discharge, it uses a static zero current to open-circuit statically discharge the power battery; in response to the end of the open-circuit statically discharge, it uses a forward charging request current to forward charge the power battery within the forward charging duration, and repeats the depolarization cycle of pulse discharge-open-circuit statically discharge-forward charging until the total depolarization duration is greater than or equal to the depolarization exit duration.

[0140] Figure 4 This is a schematic diagram of the current timing for the depolarization process provided in an embodiment of this application. Figure 4 As shown in the figure, the vertical axis represents current and the horizontal axis represents time.

[0141] like Figure 4 As shown in the diagram, t0 represents the start time of the depolarization process, t1 represents the end time of the depolarization process, and the time difference between the end time and the start time of the depolarization process is... This indicates the duration for which depolarization should exit.

[0142] During the depolarization process of the lithium plating control stage of the power battery, a single lithium plating control cycle includes three time segments, and the pulse discharge duration corresponding to the pulse discharge stage is... The open-circuit resting time corresponding to the resting relaxation stage is The forward charging phase corresponds to a forward charging duration of . .from Figure 4 As can be seen from this, after the power battery undergoes pulse discharge, open-circuit rest, and forward charging to complete one round of depolarization, the corresponding total depolarization time (i.e., , and The sum of these values ​​is less than the depolarization exit time. Therefore, the depolarization cycle consisting of this time sequence needs to be repeated on the power battery, that is, the depolarization is repeated by pulse discharge, open circuit rest and forward charging until the total depolarization time reaches the depolarization exit time and the depolarization process is terminated.

[0143] In the second round of depolarization, the open-circuit resting time corresponding to the resting relaxation phase is: Open circuit settling time With open circuit settling time They can be the same or different.

[0144] It should be noted that, Figure 4 This is merely an exemplary timing sequence. Figure 4 In the scenario shown, the total cumulative depolarization time reaches the depolarization exit time during the forward charging phase of the second round of depolarization. In actual control, the node where the total cumulative depolarization time reaches the exit condition can fall in the pulse discharge phase, the rest relaxation phase, or the forward charging phase. This application does not limit this; control can exit as long as the total cumulative depolarization time is greater than or equal to the depolarization exit time.

[0145] In this embodiment, by accumulating the total depolarization duration, the termination time of lithium plating control is matched with the duration of the depolarization process. When the lithium plating control exit condition is met, a second control command is promptly sent to the charging pile, thereby completing the switch from depolarization control to forward charging control. If the condition is not met, depolarization control continues to ensure sufficient duration for the lithium plating suppression process. With this implementation, the criterion for lithium plating control exit changes from a single state to accumulated duration, resulting in clear control logic and facilitating coordinated execution with the charging pile. Simultaneously, the combination of repeated depolarization and conditional exit allows the control process to be dynamically adjusted based on the duration, contributing to improved integrity of lithium plating control and continuity of charging recovery.

[0146] Optionally, during the depolarization process of pulse discharge of the power battery, the battery charging lithium plating control method provided in this application embodiment further includes: allocating the power battery output to the power-related devices according to a preset power allocation priority order; wherein, the power-related devices include a power load, a first energy storage battery, and a second energy storage battery.

[0147] The preset power allocation priority order is used to limit the order in which the power battery receives power output during the pulse discharge phase.

[0148] For example, the preset power allocation priority order from high to low can be: electrical load, first energy storage battery, and second energy storage battery. Accordingly, the electrical load is used to directly consume the power energy output by the power battery, the first energy storage battery is used to temporarily store the remaining power energy that has not been consumed by the electrical load, and the second energy storage battery is used to continue to absorb the remaining power energy after the first energy storage battery is used.

[0149] For example, in one possible implementation, after the pulse discharge of the power battery begins, the BMS first sends the discharge energy output by the power battery to the electrical load according to the preset power allocation priority order. If the absorption capacity of the electrical load within the current pulse window is insufficient, the remaining power is switched to the first energy storage battery for reception. When the first energy storage battery reaches the set charging conditions or there is still unused power, the remaining power is then allocated to the second energy storage battery.

[0150] For example, the electrical load can be the vehicle's electrical load, the first energy storage battery can be a 12V / 48V battery at the vehicle end, and the second energy storage battery can be an energy storage battery at the charging pile end.

[0151] Figure 5 This is a schematic diagram of the structure of the power battery and related electrical devices provided in the embodiments of this application. Figure 5 As shown, the second energy storage battery is connected to the first DC power supply. DC-DC converter to The DC Converter (DCDC) is connected to the power battery, and the electrical load and the first energy storage battery are connected to the power battery through the second DC Converter.

[0152] For example, in one possible implementation, when the BMS requests the power battery to discharge, energy is allocated sequentially to the vehicle's electrical loads, the vehicle's 12V / 48V battery, and the energy storage battery at the charging station according to a preset energy allocation priority order from high to low. The specific control strategy is as follows:

[0153] 1) When the pulse discharge current required by the BMS is less than or equal to the consumption of the vehicle's electrical load, the entire pulse discharge current is supplied to the consumption of the vehicle's electrical load, and the insufficient part is supplied by the charging pile.

[0154] 2) When the pulse discharge current required by the BMS is greater than the consumption of the vehicle's electrical load, the remaining pulse discharge current is given priority to the vehicle's 12V / 48V battery to charge the battery.

[0155] 3) When the pulse discharge current required by the BMS is greater than the sum of the vehicle load consumption and the charging capacity of the vehicle's 12V / 48V battery, the remaining pulse discharge current will be allocated to the energy storage battery at the charging pile.

[0156] Understandably, this method ensures that the electrical energy released during the pulse discharge phase is no longer simply dissipated as ineffective losses, but rather enters the current electrical load or on-board energy storage unit according to a preset energy allocation priority. While the power battery completes depolarization control, its output energy is continuously received, reducing energy interruptions and conversion steps. Because the electrical load, the first energy storage battery, and the second energy storage battery receive electrical energy sequentially, the system can maintain coordination between pulse discharge control and overall vehicle energy utilization, thereby improving the energy utilization efficiency during the pulse discharge phase.

[0157] In this embodiment, by prioritizing the supply of electrical energy output from the power battery to the vehicle's electrical loads and the vehicle's 12V / 48V battery, the number of energy conversions is reduced (the electricity received by the charging pile's energy storage battery needs to be converted again via DC-DC converter before it can be used for subsequent vehicle charging), thereby improving the efficiency of energy use.

[0158] In summary, the battery charging lithium plating control method provided in this application has the following beneficial effects:

[0159] 1) At the end of the power battery charging process, the power battery undergoes pulse discharge-rest relaxation-forward charging depolarization to eliminate concentration polarization generated during charging, which can effectively suppress lithium plating. At the same time, this depolarization operation can also dissolve reversible lithium plating generated during the previous charging process, reducing the safety risks of the power battery and improving the battery's usable capacity and cycle life.

[0160] 2) By setting a resting relaxation stage, the uneven distribution of lithium ions inside the negative electrode of the power battery can be effectively reduced, and the effect of suppressing lithium plating can be improved.

[0161] 3) By using real-time parameter information of the power battery (such as current SOC, current cell temperature, current available cell capacity and historical lithium plating level, etc.), the power control parameters corresponding to different lithium plating control stages are calculated to achieve precise control of depolarization. While suppressing and eliminating lithium plating, the charging time is reduced as much as possible, achieving a balance between the safety of power battery use and charging efficiency.

[0162] 4) During the pulse discharge process of the power battery, by adopting a discharge energy distribution strategy based on the priority of energy distribution, the number of energy conversion and transfer times is reduced, thereby improving energy utilization efficiency.

[0163] The following are embodiments of the apparatus described in this application, which can be used to execute the embodiments of the method described in this application. For details not disclosed in the apparatus embodiments of this application, please refer to the embodiments of the method described in this application.

[0164] Figure 6 This is a schematic diagram of the battery charging lithium plating control device provided in an embodiment of this application. Figure 6 As shown, the battery charging lithium plating control device 60 includes a determination module 610 and a control module 620.

[0165] Among them, the determining module 610 is used to determine whether the power battery meets the lithium plating control entry conditions during the charging process of the power battery connected to the external charging pile.

[0166] The control module 620 is used to send a first control command to the charging pile when the power battery meets the lithium plating control entry conditions. The first control command is used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages. The power control parameters are used to depolarize the power battery for the corresponding lithium plating control stage. The lithium plating control stages include pulse discharge stage, rest relaxation stage and forward charging stage.

[0167] In one possible implementation, the determining module 610 is specifically used to: acquire parameter information of the power battery, including the current SOC and the current cell temperature; and determine whether the power battery meets the lithium plating control entry conditions based on the current SOC and the current cell temperature.

[0168] In one possible implementation, the determining module 610 is further configured to: determine whether the current SOC is greater than the SOC threshold, and determine whether the current cell temperature is less than or equal to the temperature threshold; if the current SOC is greater than the SOC threshold and the current cell temperature is less than or equal to the temperature threshold, then the power battery is determined to meet the lithium plating control entry conditions; if the current SOC is less than or equal to the SOC threshold, or the current cell temperature is greater than the temperature threshold, then the power battery is determined not to meet the lithium plating control entry conditions.

[0169] In one possible implementation, the determining module 610 is further configured to: within a preset time period, determine whether the power battery meets the lithium plating control entry conditions based on the current SOC.

[0170] In one possible implementation, the parameter information also includes the current available cell capacity and historical lithium plating level. Before sending the first control command to the charging pile, the battery charging lithium plating control device also includes a calculation module (not shown), which is used to: calculate the pulse discharge current and pulse discharge duration based on the current available cell capacity, current SOC, current cell temperature and historical lithium plating level; and calculate the forward charging duration based on the current cell temperature and current SOC.

[0171] In one possible implementation, the power control parameters include pulse discharge power parameters, rest relaxation power parameters, and forward charging power parameters. The pulse discharge power parameters include pulse discharge current and pulse discharge duration, the rest relaxation power parameters include rest zero current, and the forward charging power parameters include forward charging request current and forward charging duration. The control module 620 is specifically used to: pulse discharge the power battery using the pulse discharge current within the pulse discharge duration; in response to the end of the pulse discharge, open-circuit rest the power battery using the rest zero current; and in response to the end of the open-circuit rest, forward charge the power battery using the forward charging request current within the forward charging duration.

[0172] In one possible implementation, during the open-circuit resting process of the power battery, the control module 620 is also used to: collect the battery voltage of the power battery in real time; calculate the polarization gradient of the power battery in real time based on the battery voltage; and terminate the open-circuit resting of the power battery in response to the polarization gradient being less than or equal to the polarization gradient threshold.

[0173] In one possible implementation, the determining module 610 is further configured to: obtain the total depolarization time corresponding to the depolarization process; determine whether the total depolarization time is greater than or equal to the depolarization exit time; if the total depolarization time is greater than or equal to the depolarization exit time, determine that the power battery meets the lithium plating control exit condition, and send a second control command to the charging pile, the second control command being used to instruct the charging pile to output a positive charging request current to the power battery; if the total depolarization time is less than the depolarization exit time, determine that the power battery does not meet the lithium plating control exit condition, and repeat the depolarization steps of the corresponding lithium plating control stage for the power battery.

[0174] In one possible implementation, before sending the first control command to the charging pile, the calculation module is further configured to: obtain the average charging rate and average cell temperature of the power battery within the target charging duration, wherein the target charging duration is the time difference between the start time of the current charging of the power battery and the time of entering the lithium plating control, and the lithium plating control time is the time when the power battery meets the conditions for entering the lithium plating control; and calculate the depolarization exit duration based on the average charging rate and average cell temperature.

[0175] In one possible implementation, during the depolarization process of pulse discharge of the power battery, the battery charging lithium plating control device further includes an energy distribution module (not shown), which is used to: distribute the power battery output to the power-related devices according to a preset energy distribution priority order; wherein the power-related devices include an electrical load, a first energy storage battery, and a second energy storage battery.

[0176] The battery charging lithium plating control device provided in this application embodiment can be used to execute the method steps of the above method embodiment. The specific implementation and technical effects are similar, and will not be repeated here.

[0177] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of this application. Figure 7 As shown, the electronic device 70 provided in this embodiment includes at least one processor 701 and a memory 702. Optionally, the electronic device 70 further includes a communication component 703. The processor 701, memory 702, and communication component 703 are connected via a bus 704.

[0178] In a specific implementation, at least one processor 701 executes computer execution instructions stored in memory 702, causing at least one processor 701 to perform the above-described method.

[0179] The specific implementation process of processor 701 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0180] For example, by storing computer execution instructions in a memory and having them executed by a processor in an electronic device, the electronic device is equipped with the ability to fully implement a lithium plating control method for battery charging. This allows the device to trigger corresponding control processes based on lithium plating control entry conditions during the charging process of an external charging station for the power battery. After executing the method, the processor can send corresponding control instructions to the charging station and coordinate with different lithium plating control stages to complete depolarization control for pulse discharge, rest relaxation, and forward charging. This more effectively alleviates negative electrode polarization and concentration polarization under high charge conditions, thereby promoting the reversible lithium plating re-intercalation. Therefore, it helps improve charging safety, charging efficiency, and battery lifespan retention during the final stages of fast charging.

[0181] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0182] The memory may include random access memory (RAM) and non-volatile memory (NVM), such as at least one disk storage device.

[0183] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0184] This application also provides a battery system, including a controller and a power battery;

[0185] The controller is used to execute the battery charging lithium plating control method provided in the above embodiments during the charging process of the power battery connected to an external charging pile.

[0186] Understandably, in this battery system, the controller works collaboratively with the power battery and the external charging pile. During vehicle charging, it determines whether the power battery meets the lithium plating control entry conditions. Once these conditions are met, it executes the battery charging lithium plating control method. This allows the charging pile to sequentially implement pulse discharge, rest relaxation, and forward charging depolarization control on the power battery according to the power control parameters corresponding to different lithium plating control stages. This effectively mitigates concentration polarization and negative electrode polarization under conditions prone to lithium plating, such as high SOC, low temperature, high rate, and battery aging. It further reduces existing reversible lithium plating, thereby lowering the risk of residual lithium plating at the end of charging. Therefore, it is beneficial to balance charging safety, charging efficiency, battery cycle life, and overall energy utilization efficiency.

[0187] In one possible implementation, the battery system also includes: electrical-related devices;

[0188] Electrically-related devices are connected to the power battery and are used to receive electrical energy output from the power battery during the depolarization process of pulse discharge.

[0189] For example, electrical-related devices include the vehicle's electrical loads, the vehicle's 12V / 48V battery, and the energy storage battery at the charging station.

[0190] During the depolarization process of pulse discharge of the power battery, the priority order of receiving electrical energy output from the power battery by electrical-related devices is similar to that described above, and will not be repeated here.

[0191] Understandably, by setting up electrical-related devices connected to the power battery, the electrical energy released by the power battery can be directly received during the pulse discharge phase. This allows the pulse discharge current during the depolarization process to have a clear absorption path, thereby achieving more stable controlled discharge of the power battery. This not only helps reduce the degree of electrode polarization at the end of charging and promotes the restoration of balanced lithium-ion distribution on the electrode surface and inside, but also improves the elimination effect of reversible lithium plating in conjunction with the resting relaxation phase and subsequent forward charging phase, thus enhancing the lithium plating suppression capability under high SOC, low temperature, or high rate conditions. Therefore, compared to simply completing the discharge pulse through ineffective dissipation, this scheme can improve the energy utilization efficiency of depolarization control, resulting in a better balance between charging safety, charging stability, and the vehicle's fast charging adaptability.

[0192] This application also provides an electrical device, including the battery system provided in the above embodiments.

[0193] For example, the electrical equipment can be a new energy vehicle, an energy storage power supply terminal, or other devices that require high-power battery power.

[0194] It is understood that by configuring a battery system as provided in the above embodiments in the electrical equipment, the battery management system can control the charging pile to sequentially perform pulse discharge, rest relaxation, and forward charging when the lithium plating control entry conditions are met during the charging process of the external charging pile. This enables the negative electrode polarization to be weakened more fully and the concentration accumulation to be alleviated under high charge conditions, thereby improving the ability to suppress the risk of lithium plating. At the same time, it helps to eliminate or convert the reversible lithium plating that has already formed, thereby improving the safety, capacity retention and cycle life at the end of the charging period. In this way, it can better balance charging efficiency, energy utilization efficiency and operational stability in fast charging or ultra-fast charging scenarios, and meet the higher requirements for safety and performance of high-rate charging applications.

[0195] In one possible implementation, the electrical equipment includes vehicles.

[0196] Understandably, when a vehicle is used as an electrical device, it can directly incorporate the aforementioned battery system and coordinate charging control with an external charging station through an onboard battery management system. When the vehicle meets the lithium plating control entry conditions under DC fast charging or ultra-fast charging scenarios, the battery system can sequentially perform pulse discharge, rest relaxation, and forward charging depolarization control on the power battery according to different lithium plating control stages. This more effectively alleviates negative electrode polarization and concentration polarization under high charge conditions. This promotes the re-insertion of reversible lithium plating, reduces residual lithium plating, and allows the vehicle to balance charging safety, charging efficiency, and battery cycle life at the end of charging, thereby improving the stability and practicality of new energy vehicles in high-rate charging scenarios.

[0197] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.

[0198] For example, the computer program product can be stored in the vehicle controller, the power battery management system, or a storage medium related to charging control, and after being called by the processor, it executes the judgment of lithium plating control entry conditions, the generation of control commands, and the switching control of lithium plating control stages. By implementing coordinated control of the pulse discharge stage, the rest relaxation stage, and the forward charging stage in a programmed manner, the charging pile can implement depolarization adjustment of the power battery according to the power control parameters of different lithium plating control stages, thereby more effectively mitigating negative electrode polarization and concentration accumulation in the high SOC range. This allows the already formed reversible lithium plating to obtain more sufficient conditions for elimination, thereby reducing the risk of lithium plating under low temperature, high rate, and aging conditions. Therefore, it can ensure charging safety while taking into account charging efficiency, battery cycle life, and vehicle charging applicability.

[0199] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, implement the above-described method.

[0200] For example, by pre-storing the computer execution instructions for implementing the battery charging lithium plating control method in a computer-readable storage medium, the processor can automatically execute the lithium plating control logic according to a predetermined program during vehicle charging. This allows the charging pile to stably complete depolarization control processes such as pulse discharge, rest relaxation, and forward charging sequentially after the power battery meets the lithium plating control entry conditions. This reduces differences in manual configuration and control timing deviations, resulting in more consistent control processes under high SOC, low temperature, or high-rate charging scenarios. This more effectively alleviates negative electrode polarization and reversible lithium plating residue, contributing to a balance between charging safety, charging efficiency, and battery cycle life.

[0201] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0202] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in the device.

[0203] The division of units is merely a logical functional division; 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. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices, or units, and may be electrical, mechanical, or other forms.

[0204] 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.

[0205] In addition, the functional units in the various embodiments of the present invention 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.

[0206] If a function is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this invention, or the part that contributes to the prior art, or a part 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 of the various embodiments of this invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0207] Those skilled in the art will understand that all or part of the steps of the above-described method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0208] Finally, it should be noted that other embodiments of the invention will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This invention is intended to cover any variations, uses, or adaptations of the invention that follow the general principles of the invention and include common knowledge or customary techniques in the art not disclosed herein, and is not limited to the precise structures described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of the invention is limited only by the appended claims.

Claims

1. A method for controlling lithium plating during battery charging, characterized in that, include: During the charging process of the power battery connected to an external charging pile, it is determined whether the power battery meets the lithium plating control entry conditions; If the power battery meets the lithium plating control entry conditions, a first control command is sent to the charging pile. The first control command is used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages. The power control parameters are used to depolarize the power battery for the corresponding lithium plating control stage. The lithium plating control stages include pulse discharge stage, rest relaxation stage and forward charging stage.

2. The battery charging lithium plating control method according to claim 1, characterized in that, Determining whether the power battery meets the lithium plating control entry conditions includes: Obtain the parameter information of the power battery, including the current SOC and the current cell temperature; Based on the current SOC and the current cell temperature, determine whether the power battery meets the lithium plating control entry conditions.

3. The battery charging lithium plating control method according to claim 2, characterized in that, The step of determining whether the power battery meets the lithium plating control entry conditions based on the current SOC and the current cell temperature includes: Determine whether the current SOC is greater than the SOC threshold, and determine whether the current cell temperature is less than or equal to the temperature threshold; If the current SOC is greater than the SOC threshold and the current cell temperature is less than or equal to the temperature threshold, then the power battery is determined to meet the lithium plating control entry condition. If the current SOC is less than or equal to the SOC threshold, or the current cell temperature is greater than the temperature threshold, then it is determined that the power battery does not meet the lithium plating control entry conditions.

4. The battery charging lithium plating control method according to claim 2, characterized in that, Also includes: Within a preset time period, based on the current SOC, it is determined whether the power battery meets the lithium plating control entry conditions.

5. The battery charging lithium plating control method according to claim 2, characterized in that, The parameter information also includes the current available cell capacity and historical lithium plating level, and before sending the first control command to the charging pile, it also includes: Calculate the pulse discharge current and pulse discharge duration based on the current available cell capacity, the current SOC, the current cell temperature, and the historical lithium plating level; Calculate the forward charging time based on the current cell temperature and the current SOC.

6. The battery charging lithium plating control method according to claim 5, characterized in that, The power control parameters include pulse discharge power parameters, rest relaxation power parameters, and forward charging power parameters. The pulse discharge power parameters include the pulse discharge current and the pulse discharge duration. The rest relaxation power parameters include the rest zero current. The forward charging power parameters include the forward charging request current and the forward charging duration. The depolarization of the power battery in the corresponding lithium plating control stage includes: The power battery is pulse-discharged using the pulse discharge current within the pulse discharge duration. In response to the end of pulse discharge, the power battery is left to stand in an open circuit state using the aforementioned zero-current resting method. In response to the end of the open-circuit resting period, the power battery is forward-charged using the forward charging request current during the forward charging duration.

7. The battery charging lithium plating control method according to claim 6, characterized in that, During the process of opening the circuit and allowing the power battery to rest, the method further includes: The battery voltage of the power battery is collected in real time; The polarization gradient of the power battery is calculated in real time based on the battery voltage. In response to the polarization gradient being less than or equal to the polarization gradient threshold, the open-circuit static setting of the power battery is terminated.

8. The battery charging lithium plating control method according to any one of claims 1 to 7, characterized in that, During the depolarization process of the corresponding lithium plating control stage of the power battery, the method further includes: Obtain the total depolarization duration corresponding to the depolarization process; Determine whether the total depolarization duration is greater than or equal to the depolarization exit duration; If the total depolarization duration is greater than or equal to the depolarization exit duration, then the power battery is determined to meet the lithium plating control exit condition, and a second control command is sent to the charging pile. The second control command is used to instruct the charging pile to output a positive charging request current to the power battery. If the total depolarization time is less than the depolarization exit time, it is determined that the power battery does not meet the lithium plating control exit condition, and the depolarization steps of the corresponding lithium plating control stage are repeated for the power battery.

9. The battery charging lithium plating control method according to claim 8, characterized in that, Before sending the first control command to the charging pile, the process also includes: The average charging rate and average cell temperature of the power battery within the target charging time are obtained. The target charging time is the time difference between the start time of the current charging of the power battery and the time when it enters the lithium plating control. The lithium plating control time is the time when the power battery meets the lithium plating control entry condition. The depolarization exit time is calculated based on the average charging rate and the average cell temperature.

10. The battery charging lithium plating control method according to any one of claims 1 to 7, characterized in that, In the depolarization process of pulse discharge of the power battery, the method further includes: According to the preset power allocation priority order, the power output of the power battery is allocated to the power-related devices; The power-related devices include an electrical load, a first energy storage battery, and a second energy storage battery.

11. A battery charging lithium plating control device, characterized in that, include: The determination module is used to determine whether the power battery meets the lithium plating control entry conditions during the charging process of the power battery connected to the external charging pile. The control module is used to send a first control command to the charging pile when the power battery meets the lithium plating control entry conditions. The first control command is used to indicate the power control parameters output by the charging pile to the power battery at different lithium plating control stages. The power control parameters are used to depolarize the power battery for the corresponding lithium plating control stage. The lithium plating control stages include pulse discharge stage, rest relaxation stage and forward charging stage.

12. An electronic device, characterized in that, include: Memory and processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory, causing the processor to perform the battery charging lithium plating control method as described in any one of claims 1 to 10.

13. A battery system, characterized in that, include: Controller and power battery; The controller is used to execute the battery charging lithium plating control method as described in any one of claims 1 to 10 during the charging process of the power battery connected to the external charging pile.

14. The battery system according to claim 13, characterized in that, Also includes: Electrical-related devices; The power-related device is connected to the power battery and is used to receive the electrical energy output by the power battery during the depolarization process of pulse discharge of the power battery.

15. An electrical appliance, characterized in that, Including the battery system as described in claim 13 or 14.

16. The electrical equipment according to claim 15, characterized in that, The electrical equipment includes vehicles.

17. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the battery charging lithium plating control method as described in any one of claims 1 to 10.

18. A computer program product, characterized in that, include: A computer program, which, when executed by a processor, implements the battery charging lithium plating control method as described in any one of claims 1 to 10.

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