Vehicle battery equalization processing method and electronic equipment

Abstract

The invention discloses a vehicle battery equalization processing method and electronic equipment. The method comprises the following steps: receiving historical battery data of a vehicle battery in a preset historical time period; based on the historical battery data, historical capacity differences corresponding to a plurality of single batteries included in the vehicle battery in a plurality of different operation states are determined, and the different operation states comprise a standing state and a constant current slow charging state; determining a multi-state equalization strategy (including a discharging equalization strategy, a charging equalization strategy and a standing equalization strategy) of the vehicle battery; and sending the multi-state equalization strategy and the historical capacity difference corresponding to each of the plurality of single batteries to a vehicle battery management system, so that the vehicle battery management system controls the on-off states of equalization channels corresponding to each of the plurality of single batteries. According to the invention, the technical problems that the timeliness is poor and the dynamic imbalance of the vehicle battery in the daily use process is difficult to effectively prevent and correct in the vehicle battery equalization processing method in the related technology are solved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of new energy vehicles, in particular to a vehicle battery equalization processing method and an electronic device. BACKGROUND

[0002] In recent years, the new energy vehicle market has shown an explosive growth trend. More and more consumers choose new energy vehicles as a means of transportation. The core component of new energy vehicles, the power battery pack, is usually composed of hundreds or thousands of single batteries connected in series and parallel. However, during long-term use, unbalanced phenomena are prone to occur between single batteries. This imbalance can reduce the overall performance of the battery pack, leading to a reduction in the range, an increase in charging time, and even potential safety hazards, affecting the service life of new energy vehicles and the user experience. It has also become one of the key factors restricting the further development of new energy vehicles. The battery equalization strategy currently used by most new energy vehicles mainly focuses on equalization when the vehicle is stationary and at the end of charging. This equalization method cannot monitor the capacity and state changes of each single battery in real time when the vehicle is running under complex conditions, and often only initiates equalization measures after the battery pack shows obvious imbalance, resulting in poor timeliness and difficulty in effectively preventing and correcting dynamic imbalance problems in the daily use of the battery pack.

[0003] To address the above problems, no effective solutions have been proposed so far. SUMMARY

[0004] The embodiments of the present application provide a vehicle battery equalization processing method and an electronic device to at least solve the technical problem of poor timeliness of the vehicle battery equalization processing method in the related art, which is difficult to effectively prevent and correct the dynamic imbalance of the vehicle battery in the daily use.

[0005] According to an aspect of an embodiment of the present application, a vehicle battery equalization processing method is provided, comprising: receiving historical battery data of a vehicle battery in a predetermined historical period; determining a historical capacity difference corresponding to each of a plurality of single batteries included in the vehicle battery in a plurality of different operating states based on the historical battery data, wherein the plurality of different operating states include a stationary state and a constant current slow charging state; determining a multi-state equalization strategy of the vehicle battery, wherein the multi-state equalization strategy at least includes a discharge equalization strategy, a charging equalization strategy and a stationary equalization strategy; and sending the multi-state equalization strategy and the historical capacity difference corresponding to each of the plurality of single batteries to a vehicle battery management system for the vehicle battery management system to control the switch state of an equalization channel corresponding to each of the plurality of single batteries, the equalization channel being used for capacity equalization of the single battery.

[0006] Optionally, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery in a plurality of different operating states are determined, including: based on the historical battery data, the historical capacity differences of the plurality of single batteries in the resting state are determined by: identifying resting battery data of the vehicle battery from the historical battery data, wherein the resting battery data includes resting voltage data of the plurality of single batteries, and the resting voltage data is the voltage of the corresponding single battery in the resting state; based on the resting battery data, obtaining the resting state of charge of the plurality of single batteries, wherein the resting state of charge indicates the state of charge of the corresponding single battery in the resting state; determining the maximum state of charge from the resting state of charge of the plurality of single batteries; and performing difference operation on the resting state of charge of the plurality of single batteries and the maximum state of charge to obtain the historical capacity differences of the plurality of single batteries in the resting state.

[0007] In this way, the capacity differences between the single batteries in the battery pack in a specific operating condition (i.e. the resting state) can be more accurately evaluated, thereby providing a quantitative basis for formulating discharge balancing strategies, charging balancing strategies and resting balancing strategies. Through detailed analysis and calculation, the BMS can more effectively control the switching of the balancing circuit, ensuring that the capacity balancing operation can also be accurately performed in the resting state, further improving the intelligent level of the battery management system and the overall performance of the battery pack.

[0008] Optionally, in the case that the vehicle battery is a lithium iron phosphate battery and the lithium iron phosphate battery is at the end of charging, based on the resting battery data, the resting state of charge of the plurality of single batteries is obtained, including: based on the resting voltage data of the plurality of single batteries, determining a target single battery from the plurality of single batteries, wherein the target single battery is the single battery with the maximum resting voltage data; detecting whether the resting state of charge of the target single battery is less than a first preset state of charge; and in the case that the resting state of charge of the target single battery is less than the first preset state of charge, based on the resting battery data, the resting state of charge of the plurality of single batteries is obtained.

[0009] In this way, considering the state of charge characteristics of lithium iron phosphate batteries at the end of charging, the accuracy and effectiveness of the calculation of the state of charge of such batteries can be improved, especially when the state of charge is relatively low, the resting voltage data can provide more accurate information. This can avoid the evaluation errors that may be caused by using resting voltage data at high state of charge, ensuring the intelligence and adaptability of the battery management system in lithium iron phosphate battery management, helping to maintain the performance consistency of the battery pack in complex operating conditions, prolong the battery life, and improve the stability and safety of new energy vehicles.

[0010] Optionally, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery in a plurality of different operating states are determined by: based on the historical battery data, determining the historical capacity differences of the plurality of single batteries in the constant current slow charging state by: identifying the constant current charging battery data of the vehicle battery from the historical battery data, wherein the constant current charging battery data includes the constant current charging voltage data of the plurality of single batteries, and the constant current charging voltage data is the charging voltage of the corresponding single battery in the constant current slow charging state; determining the constant current charging time of the plurality of single batteries, wherein the constant current charging time is the time when the constant current charging voltage data of the corresponding single battery reaches the voltage reference value; determining the earliest time among the constant current charging times of the plurality of single batteries; performing difference operation on the constant current charging times of the plurality of single batteries and the earliest time to obtain the time difference of the plurality of single batteries; and based on the time difference of the plurality of single batteries and the constant current value corresponding to the constant current slow charging state, obtaining the historical capacity differences of the plurality of single batteries in the constant current slow charging state.

[0011] In this way, the real capacity difference between different single batteries in the constant current slow charging state can be accurately evaluated, providing a data basis for subsequent development of multi-state balancing strategy. Since the battery reaction is more moderate during slow charging, the capacity difference between single batteries is more obvious, and through the calculation of the time difference, this difference can be more accurately reflected, thereby realizing more effective capacity balancing. In addition, the stable and predictable charging conditions under constant current charging also make the calculation of capacity difference more reliable and feasible, which helps to improve the adaptability and intelligence of the battery management system under various charging modes.

[0012] Optionally, the method further comprises: in the case of a ternary battery, determining the voltage reference value by: determining the constant current charging period corresponding to the constant current slow charging state and the middle time in the constant current charging period; determining the constant current charging voltage data of the plurality of single batteries at the middle time; and determining the maximum value of the constant current charging voltage data of the plurality of single batteries at the middle time as the voltage reference value; or in the case of a lithium iron phosphate battery, determining the voltage reference value by: determining the voltage curve of the plurality of single batteries, wherein the voltage curve represents the change process of the charging voltage of the single battery with time during the constant current charging period; and determining the charging voltage corresponding to the maximum slope in the voltage curve of the plurality of single batteries as the voltage reference value.

[0013] By the above method, for ternary batteries, a simple and direct method is adopted to determine the reference based on the maximum voltage at the intermediate time during charging; and for lithium iron phosphate batteries, the voltage at the maximum slope is found as the reference by in-depth analysis of the voltage curve, which reflects the in-depth understanding and flexible application of the battery characteristics. The above method can intelligently select the voltage reference value under constant current charging state according to the characteristics of different battery types, and provide a scientific and reasonable starting point for subsequent calculation of the historical capacity difference of the single battery.

[0014] According to another aspect of the embodiment of the application, another vehicle battery equalization processing method is also provided, which comprises: receiving historical capacity differences of a plurality of single batteries included in a vehicle battery in a plurality of different operating states and a multi-state equalization strategy of the vehicle battery sent by a cloud server, wherein the plurality of different operating states include a static state and a constant current slow charging state; the historical capacity differences are obtained based on historical battery data of the vehicle battery in a predetermined historical period; the multi-state equalization strategy at least includes a discharging equalization strategy, a charging equalization strategy and a static equalization strategy; based on the historical capacity differences of the plurality of single batteries and the multi-state equalization strategy, the switching state of the equalization channel corresponding to each single battery is controlled, wherein the equalization channel is used for capacity equalization of the single battery.

[0015] Optionally, based on the historical capacity differences of the plurality of single batteries and the multi-state equalization strategy, the switching state of the equalization channel corresponding to each single battery in the vehicle battery is controlled, comprising: in the case of detecting that the vehicle battery is switched from the static state to the discharging state, based on the discharging equalization strategy in the multi-state equalization strategy, the switching state of the equalization channel corresponding to each single battery is controlled by the following method: based on the historical capacity differences of the plurality of single batteries, the current capacity differences of the plurality of single batteries at the current time are determined; the first single battery with a current capacity difference greater than a preset first difference threshold value is identified from the plurality of single batteries, and the equalization channel corresponding to the first single battery is controlled to be turned on until the current capacity difference of the first single battery is less than the preset first difference threshold value.

[0016] By the above method, the energy difference inside the battery pack can be effectively adjusted before the vehicle starts discharging (i.e. use), avoiding performance degradation, safety problems and shortening of battery life caused by uneven energy distribution of single batteries. Through real-time monitoring and intelligent control, the BMS can seamlessly switch between various operating states of the vehicle, always keeping the battery pack in the best working state, providing stable, efficient and safe power support for the vehicle and the driver and passengers.

[0017] Optionally, based on the historical capacity difference of each of the plurality of single batteries, the current capacity difference of each of the plurality of single batteries at the current time is determined, including: obtaining the calculated capacity difference of each of the plurality of single batteries at the current time, wherein the calculated capacity difference is obtained in the same way as the historical capacity difference; taking the minimum value of the calculated capacity difference of each of the plurality of single batteries and the corresponding historical capacity difference as the current capacity difference of each of the plurality of single batteries; wherein, in the case that the vehicle battery is a lithium iron phosphate battery and the lithium iron phosphate battery is in the voltage platform period, the historical capacity difference of each of the plurality of single batteries in the static state is taken as the current capacity difference of each of the plurality of single batteries.

[0018] In this way, the BMS can accurately and reasonably evaluate and determine the capacity difference of the single battery at the current time under various battery types and operating conditions, providing a solid data foundation for subsequent equalization channel control. This strategy not only improves the intelligence and adaptability of the battery management system, but also ensures that the equalization strategy is more accurate in the special scenario of the lithium iron phosphate battery voltage platform period, avoiding potential damage to the performance and life of the battery, thereby improving the overall operating efficiency of the new energy vehicle and the user driving experience.

[0019] Optionally, the method further includes: based on the discharging equalization strategy in the multi-state equalization strategy, controlling the switching state of the equalization channel corresponding to each of the plurality of single batteries by the following way: in the case that the vehicle battery is detected to be at the end of discharging, obtaining the discharging voltage corresponding to each of the plurality of single batteries, wherein the end of discharging is used to indicate that the vehicle battery is discharged to a preset first end-of-life state; determining the lowest discharging voltage in the discharging voltage corresponding to each of the plurality of single batteries; identifying a second single battery in the plurality of single batteries whose difference between the discharging voltage and the lowest discharging voltage is greater than a first preset pressure difference threshold, and controlling the opening of the equalization channel corresponding to the second single battery until the difference between the discharging voltage and the lowest discharging voltage is less than the first preset pressure difference threshold.

[0020] In this way, the dynamic equalization control strategy is set to be applicable to the operating condition of the battery pack at the end of discharging. Through real-time monitoring and control of the discharging voltage difference of the single battery, it can be ensured that even when the battery energy is low, the energy difference between each single battery can be corrected in time, avoiding performance degradation and safety problems caused by excessive discharging of the single battery, while prolonging the overall service life of the vehicle battery. In addition, by setting a reasonable pressure difference threshold, a balance point between ensuring the overall stability of the battery pack and prolonging the life of the battery can be found, avoiding excessive equalization that may cause additional energy consumption and battery loss.

[0021] Optionally, based on the historical capacity difference of each single battery corresponding to the plurality of single batteries and the multi-state equalization strategy, the switch state of the equalization channel corresponding to each single battery in the vehicle battery is controlled, including: in the case of detecting that the vehicle battery is charged to a second preset state of charge, based on the charging equalization strategy in the multi-state equalization strategy, the switch state of the equalization channel corresponding to each single battery is controlled in the following manner: in the case of the vehicle battery being a ternary battery, the first charging voltage corresponding to each single battery of the plurality of single batteries is obtained, wherein the first charging voltage is the charging voltage of the single battery at the second preset state of charge; the lowest first charging voltage among the first charging voltages corresponding to each single battery of the plurality of single batteries is determined; the third single battery among the plurality of single batteries whose difference between the first charging voltage and the lowest first charging voltage is greater than a second preset pressure difference threshold is identified, and the opening of the equalization channel corresponding to the third single battery is controlled until the difference between the first charging voltage and the lowest first charging voltage is less than the second preset pressure difference threshold; in the case of the vehicle battery being a lithium iron phosphate battery, the historical capacity difference of each single battery of the plurality of single batteries under a constant current slow charging state is taken as the current capacity difference corresponding to each single battery; the fourth single battery among the plurality of single batteries whose current capacity difference is greater than a preset second difference threshold is identified, and the opening of the equalization channel corresponding to the fourth single battery is controlled until the current capacity difference corresponding to the fourth single battery is less than the preset second difference threshold.

[0022] In this way, whether it is a ternary battery or a lithium iron phosphate battery, the BMS can dynamically control the switch state of the equalization channel using the most suitable equalization method according to the type and real-time state of the vehicle battery, ensuring that the battery pack can also maintain good energy balance during charging, avoiding premature aging, performance degradation and safety hazards caused by energy differences between single batteries, thereby improving the comprehensive performance and service life of the new energy vehicle battery pack and ensuring the stability and safety of vehicle operation.

[0023] Optionally, the method further comprises: in the case of detecting that the vehicle battery is at the end of charging, the end of charging being used to indicate that the vehicle battery is charged to a preset second end of charge state, based on the charging equalization strategy in the multi-state equalization strategy, the switch state of the equalization channel corresponding to each single battery is controlled in the following manner: the second charging voltage corresponding to each single battery of the plurality of single batteries is obtained, wherein the second charging voltage is the charging voltage of the single battery when the end of charging is reached; the lowest second charging voltage among the second charging voltages corresponding to each single battery of the plurality of single batteries is determined; the fifth single battery among the plurality of single batteries whose difference between the second charging voltage and the lowest second charging voltage is greater than a third preset pressure difference threshold is identified, and the opening of the equalization channel corresponding to the fifth single battery is controlled until the difference between the second charging voltage and the lowest second charging voltage is less than the third preset pressure difference threshold.

[0024] By the above manner, the accurate balancing control is taken at the end of charging, not only the risk of overcharging of the battery caused by the rapid amplification of the slight voltage difference between the single batteries is prevented, the problem of affecting the battery life and safety is further avoided, but also the battery pack can output energy in the optimal state in the subsequent use process, the energy waste is reduced, and the overall efficiency of the new energy vehicle and the user satisfaction are improved.

[0025] Optionally, the method further includes: in the case that the vehicle battery is detected to be in the static state, based on the static balancing strategy in the multi-state balancing strategy, the switch state of the balancing channel corresponding to each single battery is controlled by the following manner: obtaining the current state of charge of each single battery in the static state; identifying the maximum state of charge and the minimum state of charge in the current state of charge of each single battery; in the case that the difference between the maximum state of charge and the minimum state of charge is greater than a preset difference threshold, identifying a sixth single battery whose current state of charge is greater than an average state of charge in the plurality of single batteries, wherein the average state of charge is an average value of the current state of charge of each single battery; controlling the balancing channel corresponding to the sixth single battery to be turned on until the current state of charge of the sixth single battery is less than the average state of charge.

[0026] By the above manner, the static balancing strategy is implemented during the static state of the vehicle battery, the energy imbalance problem in the battery pack caused by long-term non-use or inconsistent use mode is effectively prevented and corrected, the cycle life of the battery is prolonged, the overall performance of the battery pack is improved, the safety hazard caused by the battery imbalance is reduced, and the stability and safety of the power system of the vehicle in any state are ensured.

[0027] According to another aspect of the embodiments of the present application, an electronic device is also provided, which includes one or more processors and a memory, the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the vehicle battery balancing processing method of any one of the embodiments.

[0028] In the embodiment of the present application, by receiving historical battery data of the vehicle battery in a predetermined historical period; based on the historical battery data, determining the historical capacity difference of each single battery included in the vehicle battery corresponding to a plurality of different operating states, wherein the plurality of different operating states include the static state and the constant current slow charging state; determining the multi-state equalization strategy of the vehicle battery, wherein the multi-state equalization strategy at least includes the discharge equalization strategy, the charging equalization strategy and the static equalization strategy; sending the multi-state equalization strategy and the historical capacity difference corresponding to each single battery to the vehicle battery management system, for the vehicle battery management system to control the switch state of the equalization channel corresponding to each single battery, and the equalization channel is used for capacity equalization of the single battery. The purpose of collecting and analyzing the historical battery data to determine the historical capacity difference of the single battery in different operating states (including static, charging and discharging) is achieved. Combined with the multi-state equalization strategy of the vehicle battery, intelligent guidance is realized for the vehicle battery management system (BMS), so that it can accurately control the equalization channel of each single battery according to the current battery state, thereby realizing the technical effect of improving the timeliness of vehicle battery equalization, effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process, and further solving the technical problems of poor timeliness, difficulty in effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process in the related art. BRIEF DESCRIPTION OF DRAWINGS

[0029] The accompanying drawings, which are included to provide a further understanding of the present application and are incorporated in and constitute a part of this application, illustrate embodiments of the present application and together with the description serve to explain the present application. In the drawings:

[0030] Figure 1 is a flowchart of a vehicle battery equalization processing method according to an embodiment of the present application;

[0031] Figure 2 is a flowchart of another vehicle battery equalization processing method according to an embodiment of the present application;

[0032] Figure 3 is a flowchart of an optional vehicle battery equalization processing method according to an embodiment of the present application. DETAILED DESCRIPTION

[0033] In order to enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the accompanying drawings of the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0034] It is to be understood that the terminology "first", "second", and the like used in the specification and the claims of the application and the above-described drawings is merely intended to distinguish between similar objects and is not intended to convey a specific sequential or chronological order of steps. It is to be understood that the use of such terms can be interchanged, where appropriate, to refer to a similar object in order to convey the principle of the embodiments of the application described herein being applicable in other embodiments than those illustrated or described herein. Furthermore, the terms "comprise" and "comprising" and any variation thereof are intended to cover a non-exclusive inclusion, such that processes, methods, articles, or apparatuses that comprise a list of steps or elements do not necessarily comprise only those steps or elements that are expressly listed, but can include additional steps or elements not expressly listed or inherent to such processes, methods, articles, or apparatuses.

[0035] According to an embodiment of the application, a method embodiment of vehicle battery equalization processing is provided. It is to be understood that the steps shown in the flowcharts of the drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowcharts, in some cases, the steps shown or described herein can be executed in an order different from that shown herein.

[0036] Figure 1 is a flowchart of a method of vehicle battery equalization processing according to an embodiment of the application, as shown in Figure 1 The method comprises the following steps:

[0037] Step S102, receiving historical battery data of the vehicle battery in a predetermined historical period;

[0038] Optionally, the execution subject of steps S102 to S108 can be a cloud server (i.e. cloud), and the predetermined historical period can be obtained in days, which can be the running data of the vehicle battery collected in the past two days. That is, the vehicle battery can be equalized in days, and the historical capacity difference of each single battery of the vehicle battery in different running states is performed once a day. The data used corresponds to the historical battery data of the vehicle battery in the last two days.

[0039] Optionally, the historical battery data can be transmitted from the vehicle-side BMS wireless transmission module to the cloud according to the internal communication protocol. Specifically, the wireless transmission module of the vehicle-side BMS is used to convert the data collected by the BMS collection module according to the internal communication protocol, and send it to the specified cloud Kafka port through the TCP protocol. After the Kafka cluster of the cloud server receives the data, it will parse the data according to the internal communication protocol, and store the original data of the vehicle battery (i.e. historical battery data) into the cloud database.

[0040] In step S104, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery corresponding to a plurality of different operating states are determined, wherein the plurality of different operating states include a static state and a constant current slow charging state.

[0041] Optionally, the static state refers to that the absolute value of the current of the vehicle battery is maintained at a very low level (such as less than 500 mA) within a time period, and the time interval between the front and rear data exceeds a certain threshold (such as two hours). The constant current slow charging state refers to that the battery charging current is lower than a certain threshold (such as less than 30 A), and the charging process lasts for a period of time sufficient for the battery voltage to pass through a specific change trend. From the historical operation data of the vehicle battery, the historical capacity differences of each single battery in the static state and the constant current slow charging state are accurately determined. These capacity difference data are the basis for formulating discharge balancing strategy, charging balancing strategy and static balancing strategy, which can ensure that the battery management system (BMS) can take the optimal balancing measures according to different working conditions and battery states, so as to reduce the capacity difference between single batteries, optimize the overall performance of the battery, prolong the service life of the battery, and thus improve the reliability and user experience of new energy vehicles.

[0042] In an optional embodiment, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery corresponding to a plurality of different operating states are determined, comprising: based on the historical battery data, the historical capacity differences of the plurality of single batteries corresponding to the static state are determined by the following way: identifying the static battery data of the vehicle battery from the historical battery data, wherein the static battery data includes the static voltage data of the plurality of single batteries corresponding to the static state, and the static voltage data is the voltage of the corresponding single battery in the static state; based on the static battery data, the static state of charge of the plurality of single batteries is obtained, wherein the static state of charge is used to indicate the state of charge of the corresponding single battery in the static state; the maximum state of charge is determined from the static state of charge of the plurality of single batteries; the static state of charge of the plurality of single batteries and the maximum state of charge are subjected to difference operation to obtain the historical capacity differences of the plurality of single batteries corresponding to the static state.

[0043] Optionally, first, data records of the vehicle battery in a static state are screened from the historical battery data set. The identification of the static state can be based on the following conditions: the current of the battery fluctuates very little, that is, the absolute value of the current is below a certain threshold (such as 500 mA); and the duration of this state is relatively long, for example, the current is stable at a very low level for two consecutive hours, or the data record interval exceeds two hours. By screening through such conditions, data interference in a non-static state can be effectively eliminated, ensuring the accuracy of subsequent analysis. In the identified static battery data, the voltage data of each single battery in the static state, i.e., the static voltage data, is extracted to reflect the voltage state of each single battery in the static state. Using the extracted static voltage data, in combination with the state of charge-open circuit voltage (SOC-OCV) relationship curve or table of the battery, the state of charge (SOC) of each single battery in the static state is calculated. The SOC-OCV curve is an important embodiment of the battery characteristics, which is used for the open circuit voltage of the battery at different states of charge. By looking up this curve, the static voltage can be converted into the corresponding state of charge value. Among the calculated static states of charge of multiple single batteries, the highest state of charge value, i.e., the maximum state of charge, is found. This value represents the case of the highest state of charge among the single batteries in the static state, providing a reference for subsequent capacity difference calculation. Finally, by performing a difference operation on the static state of charge of each single battery and the maximum state of charge, the capacity difference of each single battery in the static state is obtained. This difference value can reflect the capacity loss of other single batteries relative to the single battery with the highest state of charge, which is a key indicator for measuring the balance degree of the battery pack.

[0044] In this way, the capacity differences between the single batteries in the battery pack (i.e., the vehicle battery) under a specific working condition (i.e., the static state) can be more accurately evaluated, thereby providing a quantitative basis for formulating discharge balancing strategies, charging balancing strategies, and static balancing strategies. Through detailed analysis and calculation, the BMS can more effectively control the switching of the balancing circuit, ensuring that the capacity balancing operation can also be accurately performed in the static state, further improving the intelligent level of the battery management system and the overall performance of the battery pack.

[0045] In an optional embodiment, in the case that the vehicle battery is a lithium iron phosphate battery and the lithium iron phosphate battery is at the end of charging, based on the static battery data, the static state of charge corresponding to each of the plurality of single batteries is obtained, including: determining a target single battery from the plurality of single batteries based on the static voltage data corresponding to each of the plurality of single batteries, wherein the target single battery is the single battery with the maximum static voltage data; detecting whether the static state of charge of the target single battery is less than a first preset state of charge; in the case that the static state of charge of the target single battery is less than the first preset state of charge, obtaining the static state of charge corresponding to each of the plurality of single batteries based on the static battery data.

[0046] Optionally, the SOC-OCV curve of the lithium iron phosphate battery has a complex trend, with two voltage platforms (i.e., the SOC intervals 95%-65% and 55%-35%), and only when the SOC is in the intervals 100%-95%, 65%-55%, and 35%-0%, the voltage changes relatively obviously with the capacity change. Therefore, when the lithium iron phosphate battery is at the end of charging, the highest resting voltage data of the single battery is first found from the resting battery data extracted from the historical battery data, and the single battery is defined as the target single battery. This is because at the end of charging, the battery with the highest voltage usually has the highest state of charge, which can be used as a reference point for the state of charge of the battery pack. Then, it is checked whether the resting state of charge of the target single battery is less than a preset state of charge threshold (i.e., the first preset state of charge, which can be 35% SOC). If the resting state of charge of the target single battery is indeed less than the first preset state of charge, then the resting state of charge of each of the plurality of single batteries is calculated based on the resting voltage data and the specific SOC-OCV relationship of the lithium iron phosphate battery. Since at the end of charging and at a low SOC, the voltage-SOC relationship of the vehicle battery is more direct, the resting voltage data at this time can more accurately reflect the state of charge, and thus the calculated capacity difference is more reliable.

[0047] By the above method, considering the state of charge characteristics of the lithium iron phosphate battery at the end of charging, the accuracy and effectiveness of the state of charge calculation of such battery can be improved, especially when the state of charge is relatively low, the resting voltage data can provide more accurate information. Thus, the evaluation error that may be caused by using the resting voltage data at a high state of charge can be avoided, ensuring the intelligence and adaptability of the battery management system in the management of the lithium iron phosphate battery, which helps to maintain the performance consistency of the battery pack under complex working conditions, prolong the battery life, and improve the stability and safety of the new energy vehicle.

[0048] In an optional embodiment, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery in a plurality of different operating states are determined, including: based on the historical battery data, the historical capacity differences of the plurality of single batteries in the constant current slow charging state are determined by: identifying the constant current charging battery data of the vehicle battery from the historical battery data, wherein the constant current charging battery data includes the constant current charging voltage data of the plurality of single batteries, and the constant current charging voltage data is the charging voltage of the corresponding single battery in the constant current slow charging state; determining the constant current charging time of the plurality of single batteries, wherein the constant current charging time is the time when the constant current charging voltage data of the corresponding single battery reaches the voltage reference value; determining the earliest time in the constant current charging time of the plurality of single batteries; performing difference operation on the constant current charging time of the plurality of single batteries and the earliest time to obtain the time difference of the plurality of single batteries; and based on the time difference of the plurality of single batteries and the constant current value corresponding to the constant current slow charging state, the historical capacity differences of the plurality of single batteries in the constant current slow charging state are obtained.

[0049] Optionally, the data records of the vehicle battery in the constant current slow charging state are selected from the historical battery data set. Constant current slow charging refers to the state that the charging current remains at a relatively low and stable value during the battery charging process. This state usually occurs in the middle and late stages of battery charging, at which time the current is stable and the duration is long, providing good conditions for analyzing the capacity differences of single batteries. In the identified constant current slow charging data, the voltage data of each single battery in the slow charging state (i.e. constant current charging voltage data) is extracted, which is used to reflect the voltage change of each single battery in the slow charging process. For each single battery, the time when its constant current charging voltage data reaches a preset voltage reference value is determined. The voltage reference value is a key parameter used to mark a certain point in the battery charging process, which can be set in the middle and upper regions of the battery SOC (state of charge), at which time the voltage of the battery begins to respond to the charging current more obviously, which is a good starting point for analyzing the capacity difference. Among all the constant current charging times of the single batteries, the earliest charging time is determined. The single battery with the earliest charging time can be regarded as the battery that first reaches the voltage reference value in the battery pack, and its capacity is usually the largest. Next, the difference (i.e. time difference) between the constant current charging time of each single battery reaching the voltage reference value and the earliest charging time is calculated. These time differences can reflect the time delay of different single batteries in the charging process, which is an indirect manifestation of the capacity difference. Finally, using the calculated time difference and the constant current value in the slow charging state, the historical capacity differences of the single batteries can be calculated.

[0050] By the above method, the real capacity difference between different single batteries in the constant current slow charging state can be accurately evaluated, providing a data basis for subsequent development of multi-state balancing strategy. Since the battery reaction is more moderate during slow charging, the capacity difference between single batteries is more obvious, and through the calculation of time difference, this difference can be more accurately reflected, thereby realizing more effective capacity balancing. In addition, the stable and predictable charging condition under constant current charging also makes the calculation of capacity difference more reliable and feasible, which helps to improve the adaptability and intelligence of the battery management system under various charging modes.

[0051] In an optional embodiment, the method further comprises: in the case of a ternary battery, determining the voltage reference value by: determining a constant current charging period corresponding to the constant current slow charging state, and a middle time point in the constant current charging period; determining the constant current charging voltage data of the plurality of single batteries at the middle time point respectively; determining the maximum value of the constant current charging voltage data of the plurality of single batteries at the middle time point respectively as the voltage reference value; or in the case of a lithium iron phosphate battery, determining the voltage reference value by: determining a voltage curve corresponding to each of the plurality of single batteries, wherein the voltage curve represents the charging voltage of the single battery changing with time during the constant current charging period; determining the charging voltage corresponding to the maximum slope in the voltage curve corresponding to each of the plurality of single batteries as the voltage reference value.

[0052] Optionally, for a ternary battery, first determine the charging period of the ternary battery in the constant current slow charging state from the historical data, and then find the middle time point in this period. The selection of the middle time point is based on the following considerations: during the slow charging process, the voltage change of the battery is relatively flat, but in the middle and later stages of charging, as the battery approaches saturation state, the voltage change begins to become more significant. Therefore, the middle time point often reflects the turning point of this change trend, and is a good opportunity to analyze the capacity difference of the battery. At the middle time point, the charging voltage data of each single battery is collected, and the maximum value is selected from the charging voltage data of each single battery at the middle time point as the voltage reference value. This selection is based on the characteristics of the ternary battery, i.e. during the charging process, the single battery with higher voltage often has higher state of charge, and the maximum voltage value can better reflect the charging state of the battery pack, thereby helping to accurately calculate the capacity difference.

[0053] Optionally, the voltage- state of charge (V-SOC) curve of the lithium iron phosphate battery has a unique double-platform characteristic, so when determining the voltage reference value, the voltage curve of each single battery during the constant-current slow charging period needs to be analyzed to observe the process of voltage change over time. In the voltage curve, the charging voltage corresponding to the maximum slope (voltage change rate) is sought, which often occurs in a certain interval of SOC, for example, between 55% and 65%. The maximum slope means that the voltage change is most significant, and the voltage value at this time can better reflect the change of the battery state of charge, and is suitable as a voltage reference value. The charging voltage corresponding to the maximum slope found above is determined as the voltage reference value. This strategy makes full use of the characteristics of the lithium iron phosphate battery voltage curve, and selects the most representative and most obvious point in the voltage curve as the reference, which helps to more accurately evaluate the capacity difference of the single batteries in the battery pack.

[0054] In the above manner, for ternary batteries, a simple and direct method is adopted to determine the reference based on the maximum voltage at the intermediate time during charging; while for lithium iron phosphate batteries, the voltage at the maximum slope is sought as the reference by in-depth analysis of the voltage curve, which reflects the in-depth understanding and flexible application of the characteristics of the battery. The above manner can intelligently select the voltage reference value under constant-current charging state according to the characteristics of different battery types, providing a scientific and reasonable starting point for subsequent calculation of the historical capacity difference of the single batteries.

[0055] In step S106, a multi-state equalization strategy of the vehicle battery is determined, wherein the multi-state equalization strategy at least includes a discharging equalization strategy, a charging equalization strategy, and a static equalization strategy.

[0056] Optionally, the discharging equalization strategy is started during the battery discharging process, and the target is to reduce the capacity difference between the single batteries. In the discharging equalization, the charging equalization strategy focuses on equalizing the state of charge of the single batteries by adjusting the charging current or activating the active equalization circuit during the battery charging process, especially when the charging is about to end. When the vehicle is stationary for a long time, the static equalization strategy can perform passive equalization or voltage-based equalization through weak current circulation or open-circuit voltage (OCV) detection. In the static state, the current of the battery pack is very low, which provides favorable conditions for adjusting the voltage of the single batteries through the equalization circuit. According to the different operating states of the battery and the historical capacity difference data, the most suitable equalization method is adopted to ensure that the capacity difference between the single batteries can be effectively reduced in various working conditions, and the overall energy utilization efficiency of the battery pack and the cycle life of the battery pack are improved.

[0057] In step S108, the multi-state equalization strategy and the historical capacity difference corresponding to each single battery are sent to the vehicle battery management system, which is used to control the switching state of the equalization channel corresponding to each single battery for capacity equalization of the single battery.

[0058] Optionally, by sending the multi-state balancing strategy and the historical capacity difference data of the single batteries to the vehicle battery management system (BMS), the BMS can dynamically adjust the switching state of the balancing circuit according to the current operating state of the battery, thereby achieving precise control of the capacity balancing of the single batteries. This process not only takes into account the immediate state of the vehicle battery, but also considers the historical performance of the vehicle battery under different operating states, ensuring the rationality and effectiveness of the balancing strategy.

[0059] Optionally, the multi-state balancing strategy can be distributed to the BMS wireless communication module at the vehicle end through an internal communication protocol. The multi-state balancing strategy and the capacity difference of each single battery formulated by the cloud are transmitted to the BMS at the vehicle end through the downlink data format declared by the internal communication protocol. After receiving, the BMS implements the cloud multi-state balancing strategy according to the state of the vehicle battery pack, and opens the balancing channel of the corresponding single battery.

[0060] Optionally, the BMS can determine whether to start adjusting the opening and closing of the balancing channel of each single battery according to the temperature information of the vehicle battery, whether the balancing channel of each single battery is abnormal, and the credibility of the historical capacity difference of each single battery transmitted by the cloud server. The credibility of the historical capacity difference can be measured by the difference between the current capacity difference of each single battery calculated by the BMS system and the corresponding historical capacity difference. If the difference is greater than a certain threshold (such as 5% SOC), it is determined that the historical capacity difference transmitted by the cloud server this time is not reliable, and the historical capacity difference is not updated. Otherwise, it is determined that the historical capacity difference transmitted by the cloud server this time is reliable, and the BMS system can update the historical capacity difference of each single battery it holds to the latest historical capacity difference transmitted by the cloud server.

[0061] For example, the BMS can determine to start the process of adjusting the opening and closing of the balancing channel of each single battery when it detects that the temperature of the vehicle battery is less than a preset temperature threshold, the balancing channel of each single battery is normal, and the historical capacity difference of each single battery transmitted by the cloud server is reliable. Otherwise, the process of adjusting the opening and closing of the balancing channel of each single battery is not started, thereby ensuring the smooth progress of this capacity balancing.

[0062] Through the steps S102 to S108, the historical battery data can be collected and analyzed to determine the historical capacity difference of the single battery under different operating states (including static, charging and discharging), and the multi-state balancing strategy of the vehicle battery is combined to realize the intelligent guidance of the vehicle battery management system (BMS), so that the balancing channel of each single battery can be accurately controlled according to the current battery state, thereby realizing the technical effect of improving the timeliness of vehicle battery balancing, effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process, and further solving the technical problems of poor timeliness of the vehicle battery balancing processing method in the related art, and difficulty in effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process.

[0063] According to the embodiments of the present application, a vehicle battery balancing processing method embodiment is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although the logical order is shown in the flowchart, in some cases, the steps shown or described herein can be executed in a different order.

[0064] Figure 2 is a flowchart of the vehicle battery balancing processing method according to the embodiments of the present application, as shown in Figure 2 The method comprises the following steps:

[0065] Step S202, receiving the historical capacity difference of each single battery included in the vehicle battery under a plurality of different operating states and the multi-state balancing strategy of the vehicle battery sent by the cloud server, wherein the plurality of different operating states include static state and constant current slow charging state; the historical capacity difference is obtained based on the historical battery data of the vehicle battery in a predetermined historical period; and the multi-state balancing strategy at least includes discharging balancing strategy, charging balancing strategy and static balancing strategy.

[0066] Step S204, based on the historical capacity difference of each single battery and the multi-state balancing strategy, control the switch state of the balancing channel corresponding to each single battery, wherein the balancing channel is used for capacity balancing of the single battery.

[0067] The execution subject of steps S202 to S204 can be the BMS system. Through the above steps S202 to S204, the historical battery data can be collected and analyzed to determine the historical capacity difference of the single battery under different operating states (including static, charging and discharging), and the multi-state balancing strategy of the vehicle battery is combined to realize the intelligent guidance of the BMS, so that the balancing channel of each single battery can be accurately controlled according to the current battery state, thereby realizing the technical effect of improving the timeliness of vehicle battery balancing, effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process, and further solving the technical problems of poor timeliness of the vehicle battery balancing processing method in the related art, and difficulty in effectively preventing and correcting the dynamic imbalance of the vehicle battery in the daily use process.

[0068] In an optional embodiment, based on the historical capacity difference of each single battery corresponding to the multi-state balancing strategy, the switch state of the balancing channel corresponding to each single battery in the vehicle battery is controlled, including: in the case of detecting that the vehicle battery is switched from the static state to the discharging state, based on the discharging balancing strategy in the multi-state balancing strategy, the switch state of the balancing channel corresponding to each single battery in the vehicle battery is controlled by the following method: based on the historical capacity difference of each single battery, the current capacity difference of each single battery at the current time is determined; identify the first single battery with a current capacity difference greater than a preset first difference threshold value among the plurality of single batteries, and control the opening of the balancing channel corresponding to the first single battery until the current capacity difference corresponding to the first single battery is less than the preset first difference threshold value.

[0069] Optionally, the battery management system (BMS) continuously monitors the state of the vehicle battery, and when it detects that the vehicle battery switches from the resting state to the discharging state, it initiates the execution of the discharging equalization strategy. The switch from resting to discharging means that the vehicle is about to enter or has entered the use stage, at which time it is particularly important to adjust the energy balance within the battery pack to ensure that all single batteries can effectively participate in energy output and avoid limiting the performance of the entire battery pack due to insufficient energy of single batteries. Based on historical capacity difference data, combined with the current state of charge (SOC) of the battery and other real-time operating parameters, the capacity difference of all single batteries at the current time is calculated. A difference threshold (a preset first difference threshold, such as 2% SOC) in the discharging equalization strategy is preset to determine whether the capacity difference between single batteries has reached the level that requires equalization. The BMS identifies all single batteries whose current capacity difference is greater than the preset first difference threshold (i.e., first single batteries). For these first single batteries with significantly lower capacity, the BMS automatically opens their equalization channels to allow energy transfer from single batteries with more abundant energy in the battery pack to the first single batteries, thereby reducing the energy difference between them and other single batteries in the pack. The opening of the equalization channel will continue until the current capacity difference of the first single battery decreases to below the preset first difference threshold, i.e., reaches or approaches the equalization state of the energy distribution within the battery pack.

[0070] In this way, it can be ensured that the energy difference within the battery pack is effectively adjusted before the vehicle begins to discharge (i.e., use), avoiding performance degradation, safety problems, and shortened battery life caused by uneven energy distribution among single batteries. Through real-time monitoring and intelligent control, the BMS can seamlessly switch between various operating states of the vehicle, always maintaining the battery pack in the best working state to provide stable, efficient, and safe power support for the vehicle and passengers.

[0071] In an optional embodiment, based on the historical capacity difference of each of the plurality of single batteries, the current capacity difference of each of the plurality of single batteries at the current time is determined, including: obtaining the calculated capacity difference of each of the plurality of single batteries at the current time, wherein the calculated capacity difference is obtained in the same way as the historical capacity difference; taking the minimum value of the calculated capacity difference of each of the plurality of single batteries and the corresponding historical capacity difference as the current capacity difference of each of the plurality of single batteries; wherein, when the vehicle battery is a lithium iron phosphate battery, and the lithium iron phosphate battery is in the voltage platform period, the historical capacity difference of each of the plurality of single batteries in the resting state is taken as the current capacity difference of each of the plurality of single batteries.

[0072] Optionally, first, the BMS needs to obtain the current time of each corresponding single battery calculation capacity difference. This calculation of the capacity difference is the same as the calculation of the historical capacity difference (i.e. received from the cloud, based on the past battery operation data calculated capacity difference), which involves real-time measurement and analysis of battery voltage, current and SOC and other parameters, to reflect the energy distribution imbalance of the battery pack under the current working condition. Next, compare the calculated capacity difference of each single battery with the minimum value of its corresponding historical capacity difference, and select the smaller value of the two as the current capacity difference. This logic is based on the following considerations: historical capacity difference data may reflect the long-term running trend of the battery to some extent, but the instantaneous change of the current working condition may also cause temporary fluctuations in the capacity difference. By selecting the smaller value of the calculated capacity difference and the minimum historical capacity difference, the long-term state and current working condition of the battery can be considered, providing a more robust and conservative evaluation result, avoiding unnecessary equalization operation due to instantaneous fluctuations.

[0073] It should be noted that for lithium iron phosphate batteries, when they are in the voltage platform period, the historical capacity difference of each corresponding single battery in the resting state is used as the current capacity difference. This is because when the lithium iron phosphate battery is in the voltage platform period, the relationship between SOC and voltage becomes more complex, and the voltage changes relatively flat. The capacity difference calculated based on real-time voltage or current data may not be accurate or misleading. While the battery data in the resting state, due to the more direct and linear relationship between voltage and SOC, can provide a relatively reliable capacity difference reference value, suitable for equalization strategy formulation in the voltage platform period.

[0074] Through the above way, the BMS can accurately and reasonably evaluate and determine the capacity difference of the single battery at the current time under various battery types and operating conditions, providing a solid data foundation for subsequent equalization channel control. This strategy not only improves the intelligence and adaptability of the battery management system, but also ensures that the equalization strategy in the voltage platform period of lithium iron phosphate batteries, a special scenario, can be more accurate, avoiding potential damage to battery performance and life, thereby improving the overall operating efficiency of new energy vehicles and user driving experience.

[0075] In an optional embodiment, the method further comprises: based on the discharging equalization strategy in the polymorphic equalization strategy, controlling the switch state of the equalization channel corresponding to each of the plurality of single batteries by: in the case of detecting that the vehicle battery is at the discharging end, acquiring the discharging voltage corresponding to each of the plurality of single batteries, wherein the discharging end is used to indicate that the vehicle battery is discharged to a preset first end-of-charge state; determining the lowest discharging voltage among the discharging voltages corresponding to each of the plurality of single batteries; identifying a second single battery among the plurality of single batteries whose discharging voltage difference from the lowest discharging voltage is greater than a first preset voltage difference threshold; and controlling the opening of the equalization channel corresponding to the second single battery until the discharging voltage difference from the lowest discharging voltage is less than the first preset voltage difference threshold.

[0076] Optionally, the BMS continuously monitors the state of charge (SOC) of the vehicle battery, and when it is detected that the battery is discharged to a preset first end-of-charge state (such as 5% SOC), it is considered that the vehicle battery is at the discharging end. The judgment of the discharging end can ensure that the equalization strategy can be started in time when the battery energy is close to depletion, so as to reduce the voltage and energy differences between the single batteries. When the discharging end is detected, the BMS needs to acquire the discharging voltage of all single batteries at the current time. These voltage data can reflect the energy level of each single battery in the battery pack (i.e. the vehicle battery). Then, the lowest discharging voltage is determined from all the discharging voltages, and the single battery corresponding to this voltage value has the highest energy efficiency and the most sufficient remaining energy, which is suitable as a reference point for energy equalization. The BMS identifies the single battery (i.e. the second single battery) among all single batteries whose discharging voltage difference from the lowest discharging voltage is greater than a first preset voltage difference threshold (such as 50mv). The energy level of these second single batteries is relatively low, and there is a significant difference from the batteries with sufficient energy in the group. For these batteries, the BMS will automatically open their equalization channels, allowing energy transfer from the single batteries with sufficient energy to the second single batteries with insufficient energy, until the voltage difference between all single batteries is reduced to below the first preset voltage difference threshold, i.e. reaching or approaching the equalization state of the battery pack energy distribution.

[0077] In this way, the dynamic equalization control strategy is suitable for the working condition of the battery pack at the discharging end. Through real-time monitoring and control of the discharging voltage difference of the single batteries, it can be ensured that even when the battery energy is low, the energy difference between each single battery can be corrected in time, avoiding performance degradation and safety problems caused by excessive discharge of single batteries, while prolonging the overall service life of the vehicle battery. In addition, by setting a reasonable voltage difference threshold, a balance point between ensuring the overall stability of the battery pack and prolonging the battery life can be found, avoiding excessive equalization that may cause additional energy consumption and battery loss.

[0078] In an optional embodiment, based on the historical capacity difference of each monomer battery corresponding to the multi-state equalization strategy, the switch state of the equalization channel corresponding to each monomer battery in the vehicle battery is controlled, including: in the case of detecting that the vehicle battery is charged to the second preset state of charge, based on the charging equalization strategy in the multi-state equalization strategy, the switch state of the equalization channel corresponding to each monomer battery is controlled in the following way: in the case of the vehicle battery being a ternary battery, the first charging voltage corresponding to each monomer battery is obtained, wherein the first charging voltage is the charging voltage of the monomer battery at the second preset state of charge; the lowest first charging voltage among the charging voltages corresponding to the plurality of monomer batteries is determined; the third monomer battery whose difference between the first charging voltage and the lowest first charging voltage is greater than a second preset voltage difference threshold is identified among the plurality of monomer batteries, and the equalization channel corresponding to the third monomer battery is controlled to be opened until the difference between the first charging voltage and the lowest first charging voltage is less than the second preset voltage difference threshold; in the case of the vehicle battery being a lithium iron phosphate battery, the historical capacity difference of each monomer battery under constant current slow charging is taken as the current capacity difference of each monomer battery; the fourth monomer battery whose current capacity difference is greater than a preset second difference threshold is identified among the plurality of monomer batteries, and the equalization channel corresponding to the fourth monomer battery is controlled to be opened until the current capacity difference corresponding to the fourth monomer battery is less than the preset second difference threshold.

[0079] Optionally, for ternary batteries, the BMS continuously monitors the state of charge (SOC) of the vehicle battery, and when the battery is charged to a pre-set second preset state of charge, the execution of the charging equalization strategy is triggered. The second preset state of charge can be 50% SOC, which is an ideal window period for battery equalization operation, because in this SOC range, the voltage difference of the monomer battery is more obvious, and it is easy to reduce the difference through equalization processing. When it is detected that the battery reaches the second preset state of charge, the BMS records and analyzes the first charging voltage of each monomer battery at this SOC state. Then, the lowest first charging voltage is found from the first charging voltages of all monomer batteries. The BMS identifies the monomer battery (i.e. the third monomer battery) among all monomer batteries whose difference between the first charging voltage and the lowest first charging voltage is greater than a second preset voltage difference threshold (such as 50mv). The energy level of these monomer batteries is lower than that of other batteries in the group, so the BMS will automatically open their equalization channels, allowing energy transfer from higher energy batteries to the third monomer battery with insufficient energy, until the voltage difference between all monomer batteries is reduced to below the second preset voltage difference threshold, achieving equalization of energy in the battery pack.

[0080] Optionally, when the lithium iron phosphate battery is charged to a certain state of charge, the BMS no longer relies on real-time voltage data to calculate the capacity difference, but directly uses the historical capacity difference data calculated in the constant current slow charging state as the current capacity difference. This is because the voltage of the lithium iron phosphate battery is relatively sluggish in some SOC intervals, and using historical capacity difference can more accurately reflect the true state of the battery. The BMS identifies all single batteries whose current capacity difference is greater than a preset second difference threshold (such as 2% SOC) (i.e., the fourth single battery). The difference in energy distribution between these single batteries and other batteries in the group has reached the level that requires equalization intervention. For these batteries, the BMS will turn on their equalization channels to transfer energy until the capacity difference of each single battery is reduced to below the preset second difference threshold, completing the energy equalization in the charging state.

[0081] In this way, whether it is a ternary battery or a lithium iron phosphate battery, the BMS can dynamically control the switching state of the equalization channel according to the type and real-time state of the vehicle battery, using the most suitable equalization method to ensure that the battery pack can also maintain good energy equalization during charging. Avoid premature aging, performance degradation and safety hazards caused by energy differences between single batteries, thereby improving the overall performance and service life of the new energy vehicle battery pack and ensuring the stability and safety of vehicle operation.

[0082] In an optional embodiment, the method further comprises: in the case of detecting that the vehicle battery is at the end of charging, the end of charging being used to indicate that the vehicle battery is charged to a preset second end of charge state, based on the charging equalization strategy in the multi-state equalization strategy, controlling the switching state of the equalization channel corresponding to each of the plurality of single batteries by: obtaining a second charging voltage corresponding to each of the plurality of single batteries, wherein the second charging voltage is the charging voltage of the single battery when it reaches the end of charging; determining the lowest second charging voltage among the second charging voltages corresponding to each of the plurality of single batteries; identifying a fifth single battery among the plurality of single batteries whose difference between the second charging voltage and the lowest second charging voltage is greater than a third preset voltage difference threshold; and controlling the opening of the equalization channel corresponding to the fifth single battery until the difference between the second charging voltage and the lowest second charging voltage is less than the third preset voltage difference threshold.

[0083] Optionally, the BMS continuously monitors the charging process of the vehicle battery, and once it detects that the vehicle battery is charged to a preset second end-of-charge state (e.g., 95% SOC), i.e., the end-of-charge, it activates a specific balancing strategy. The end-of-charge marks that the battery is close to being fully charged. Upon detecting that the battery reaches the end-of-charge, the BMS collects the charging voltages of all the single batteries at this SOC state (i.e., second charging voltages). These voltage data can reflect the energy levels of the single batteries at the end-of-charge. Then, the lowest second charging voltage is determined from all the second charging voltages. The BMS identifies the single batteries (i.e., fifth single batteries) among all the single batteries, for which the difference between the second charging voltage and the lowest second charging voltage is greater than a third preset voltage difference threshold (e.g., 20 mv). This means that these single batteries are significantly different in energy from the single battery with the lowest energy in the pack, and need to be subjected to energy balancing. For these fifth single batteries, the BMS will automatically open their balancing channels to allow energy transfer until the voltage difference between all the single batteries falls below the third preset voltage difference threshold, i.e., energy balancing at the end-of-charge state is achieved.

[0084] In this way, precise balancing control is taken at the end-of-charge, which not only prevents the risk of overcharging of the battery due to rapid amplification of the slight voltage difference between the single batteries, thereby affecting the battery life and safety, but also ensures that the battery pack can output energy in the optimal state in subsequent use, reduces energy waste, and improves the overall efficiency of new energy vehicles and user satisfaction.

[0085] In an optional embodiment, the method further comprises: in the case where it is detected that the vehicle battery is in a stationary state, controlling the switching state of the balancing channel corresponding to each of the plurality of single batteries based on the stationary balancing strategy in the multi-state balancing strategy by: obtaining the current state of charge of each of the plurality of single batteries in the stationary state; identifying the maximum state of charge and the minimum state of charge in the current state of charge of each of the plurality of single batteries; in the case where the difference between the maximum state of charge and the minimum state of charge is greater than a preset difference threshold, identifying a sixth single battery among the plurality of single batteries, for which the current state of charge is greater than an average state of charge, wherein the average state of charge is the average of the current state of charge of each of the plurality of single batteries; controlling the balancing channel corresponding to the sixth single battery to be opened until the current state of charge of the sixth single battery is less than the average state of charge.

[0086] Optionally, the BMS continuously monitors the state of the vehicle battery, and when it detects that the vehicle battery is in a stationary state, i.e. the vehicle is not in use, the vehicle battery is neither discharging nor charging, it initiates a stationary equalization strategy. In the stationary state, the BMS records the current state of charge (SOC) of each monobloc battery. This data can reflect the energy state of each monobloc in the battery pack. Next, the BMS analyzes the current state of charge of all monoblocs, determines the maximum state of charge and the minimum state of charge among them, and calculates the difference between the two. If this difference is greater than a preset difference threshold (such as 3% SOC), i.e. the condition for equalization operation is reached, indicating that the energy imbalance problem in the battery pack is relatively significant, measures need to be taken to prevent battery aging acceleration and performance decline. The BMS further identifies all monoblocs whose current state of charge is greater than the average state of charge (i.e. the sixth monobloc). The average state of charge is calculated from the average of the current state of charge of all monoblocs, representing the desired state of energy distribution in the battery pack. For these sixth monoblocs, i.e. monoblocs with relatively excessive energy, the BMS will open their equalization channels to allow energy to transfer to monoblocs with insufficient energy until the state of charge of these monoblocs drops to or approaches the average state of charge, thereby achieving the goal of equalizing energy in the pack.

[0087] In this way, by setting a stationary equalization strategy during the stationary period of the vehicle battery, the energy imbalance problem in the battery pack caused by long-term non-use or inconsistent use patterns can be effectively prevented and corrected, prolonging the cycle life of the battery and improving the overall performance of the battery pack. At the same time, it reduces the safety hazards caused by battery imbalance, ensuring the stability and safety of the power system of the vehicle in any state.

[0088] As an optional embodiment, the next equalization strategy can also be optimized based on the results of the last equalization strategy. By analyzing the data performance of the BMS after implementing the cloud equalization strategy, the capacity difference of each monobloc after equalization is obtained, compared with the capacity difference of each monobloc before implementing the strategy, and the average of the capacity difference change of each monobloc after equalization is calculated. The predicted equalization capacity of the original monobloc capacity difference is divided by the equalization coefficient of the next equalization to obtain the equalization coefficient of the next equalization. When formulating the cloud equalization strategy next time, multiply the predicted equalization capacity by the equalization coefficient to obtain the predicted equalization capacity next time, and repeat the cycle to continuously narrow the capacity difference.

[0089] Based on the above embodiments and optional embodiments, the application proposes an optional implementation of a vehicle battery balancing processing method, which uses a lightweight balancing algorithm at the vehicle end, and completes complex calculation and strategy iteration in the cloud. The method reduces the cost of on-board hardware, and uses the supercomputing capability of the cloud to realize concurrent optimization of balancing strategies for millions of vehicles, significantly improves the global energy utilization efficiency, and relies on high-frequency data collection (sampling period ≤10 ms) at the vehicle end and millisecond-level decision feedback in the cloud. Breakthrough the limitation that BMS is only triggered in static scenarios in related technologies, realize real-time correction of cell capacity deviation in vehicle driving, charging and static conditions, significantly improve the balancing response speed, and greatly extend the battery cycle life. Figure 3 is a flowchart of an optional vehicle battery balancing processing method according to an embodiment of the application, as shown in Figure 3 , the method comprises:

[0090] S1, according to the internal communication protocol, receiving the battery raw data from the wireless transmission module of the vehicle end BMS, using the wireless transmission module of the vehicle end BMS, converting the data collected by the BMS collection module according to the internal communication protocol, and sending it to the specified cloud Kafka port through the TCP protocol. After the Kafka cluster of the cloud server receives the data, it will analyze the data according to the internal communication protocol, and store the raw data of the vehicle battery (i.e. historical battery data) into the cloud database.

[0091] S2, estimating the capacity difference of each single cell of the vehicle in multiple states according to the historical battery data. Specifically, cleaning the vehicle battery raw data, extracting the features of the cleaned data, and using different single cell capacity difference estimation methods according to the different battery types of ternary batteries and iron lithium batteries.

[0092] The single cell capacity difference estimation method for ternary batteries in two different states (i.e. static state and constant current slow charging state) can be but not limited to the following way:

[0093] For the case of long static state, first, the cleaned data needs to be sorted by time, and the following two conditions are met to determine the data after static: the time interval between the front and back two data is more than two hours or the absolute value of the current data within two hours is always kept within 500mA, filter the vehicle data that meets the above static condition, and the voltage data of the vehicle after static {V0, V1, V2, V3, …, V n} corresponding to the vehicle, according to the linear refinement of the battery state of charge-open circuit voltage relationship table (i.e. SOC-OCV table) of the project vehicle, calculate the SOC value of each single cell {SOC0, SOC1, SOC2, SOC3, …, SOC n} and the capacity difference of each monomer battery is obtained by subtracting the SOC value of other monomer batteries from the maximum SOC value in the array {ΔSOC0, ΔSOC1, ΔSOC2, ΔSOC3, …, ΔSOC n} and the capacity difference is used as the historical capacity difference of each monomer battery in the static state;

[0094] For the constant current slow charging state, the judgment of the state needs to analyze the current and charging state of the data, and needs to find the charging data in which the continuous charging current remains stable. The duration of the charging needs to be judged according to the size of the stable current, and the charging duration T should be greater than For the vehicle data satisfying the above conditions, a voltage reference value V is determined. The voltage reference value can use the maximum voltage value at the middle time point of the stable charging current. In this way, not only can it be ensured that the charging has been performed for a period of time, and the capacity difference originally existing in each monomer has appeared, but also most of the monomers can reach the voltage reference value during the entire charging period. After the voltage reference value is determined, the time {T0, T1, T2, T3, …, T n} is calculated. The time difference (i.e., the time difference) of each monomer is obtained by subtracting the time (i.e., the time) at which the voltage is reached earliest from the time of each monomer battery {ΔT0, ΔT1, ΔT2, ΔT3, …, ΔT n} In this way, the capacity difference of each monomer and the maximum capacity monomer can be obtained as follows: The capacity difference of all monomers obtained by the above method {ΔSOC0, ΔSOC1, ΔSOC2, ΔSOC3, …, ΔSOC n} is used as the historical capacity difference of each monomer battery in the constant current slow charging state. The calculation of each capacity difference of the lithium iron phosphate battery is more complex than that of the ternary battery. The SOC-OCV curve of the ternary battery is linear, and the relationship between the voltage and the capacity is linear.

[0095] However, the SOC-OCV curve of the lithium iron phosphate battery has a complex trend, and there are two voltage platforms (i.e., the SOC intervals 95%-65% and 55%-35%). Only when the SOC interval is 100%-95%, 65%-55%, and 35%-0%, the voltage changes relatively obviously when the capacity changes. Therefore, the capacity difference of each monomer is estimated in two states (i.e., the static state and the constant current slow charging state) in this embodiment:

[0096] For vehicles that have been left undisturbed for an extended period and are at the end of their discharge cycle, the voltage change caused by the capacity change at the end of the discharge cycle is more significant. Therefore, estimating the capacity based on the voltage is more accurate. The method for finding the undisturbed data is the same as that used for ternary lithium batteries. The time interval between two data points exceeds two hours, or the absolute value of the current in the data points remains within 500mA within a certain two-hour period. In addition, it is necessary to determine whether the SOC of the single cell with the highest voltage in the voltage array after undisturbed operation is less than 35%. This filters out the vehicles and estimates the SOC value of each single cell {SOC0, SOC1, SOC2, SOC3, ..., SOCV} based on the SOC-OCV curve. n Find the largest SOC value in the array and subtract it from the SOC values ​​of other units to obtain the capacity difference {ΔSOC0, ΔSOC1, ΔSOC2, ΔSOC3, ..., ΔSOC} of each unit. n The above capacity difference is used as the historical capacity difference of each individual cell under static conditions.

[0097] For constant current slow charging, this state requires a stable charging current of less than 30A and ensures that each cell passes through two voltage plateau periods during the charging process. During charging, the voltage change of a single cell is relatively significant as the State of Charge (SOC) transitions from 55% to 65%. The slope of the voltage curve can be used to determine this voltage change. Finding a curve where the slope is initially 0, gradually increases, and then decreases again, allows us to pinpoint the SOC of a single cell within the 55%-65% range. The maximum voltage value of the voltage array at the point of maximum slope can then be used as a voltage reference value. The time it takes for each cell to reach this reference value during slow charging is calculated, resulting in {T0, T1, T2, T3, ..., T...}. n By subtracting the earliest arrival time of voltage from the time of each individual cell, we can obtain the time difference {ΔT0, ΔT1, ΔT2, ΔT3, ..., ΔT} for each individual cell. n Thus, the capacity difference between each individual unit and the unit with the largest capacity is: This yields the capacity differences of all individual cells {ΔSOC0, ΔSOC1, ΔSOC2, ΔSOC3, ..., ΔSOC}. n The obtained capacity difference is then used as the historical capacity difference of each individual battery cell under constant current slow charging conditions. Based on the above method, a daily scheduled task can be set to calculate the historical capacity difference of each individual battery cell in all vehicle batteries over the past two days, and store the most recently calculated historical capacity difference data of each individual battery cell in the database for use as estimation data of the capacity difference of each individual cell in the vehicle battery pack.

[0098] S3, form a multi-state equalization strategy according to the equalization ability of each battery pack, use the equalization ability information of each vehicle transmitted by the vehicle end to form a suitable multi-state equalization strategy. The multi-state equalization strategy mainly includes the equalization strategy during discharging (i.e. discharging equalization strategy), the equalization strategy during charging (i.e. charging equalization strategy) and the equalization strategy in the static state (i.e. static equalization strategy).

[0099] For the discharging equalization strategy: when the cloud (i.e. cloud server) detects that the vehicle is powered on and starts to send battery data, it is determined whether the past historical data of the current power-on data meets the static condition. If the static condition is met, the SOC values of each battery monomer at the current time {SOC0, SOC1, SOC2, SOC3, …, SOC n} are calculated by the SOC-OCV table lookup method. The result is compared with the capacity difference of each monomer calculated in the last step S2, and the smaller result is taken as the final capacity difference of each monomer (i.e. the current capacity difference of each monomer battery). If the voltage of the lithium iron phosphate battery is in the voltage platform period, the OCV table lookup calculation is not performed, and the calculation result of step S2 is used as the final result. After obtaining the capacity difference of each monomer, passive equalization is started for all monomers with a capacity difference greater than 2% of the lowest capacity monomer according to the equalization ability transmitted by each vehicle. The equalization capacity difference is expected to be 20%, which prevents over-equalization, so the equalization time can be set as the ΔSOC of this monomer and the lowest capacity monomer divided by the equalization ability per unit time. In addition to equalization during discharging after power-on, high-voltage monomers with a large pressure difference from the lowest voltage at the end of discharging can also be equalized. The equalization channel is opened until the pressure difference is less than 50mv. The equalization strategy at the end of discharging is not suitable for monomers with abnormal internal resistance.

[0100] For the charging equalization strategy: when charging to about 50% SOC, monomers with a pressure difference greater than 50mv from the lowest voltage are opened to equalization channel until the pressure difference is less than 50mv. For lithium iron phosphate batteries, through the judgment of the platform period of lithium iron phosphate batteries in step S2, the historical capacity difference of each monomer battery is calculated according to the constant current slow charging state in step S2. Passive equalization is started for all monomers with a capacity difference greater than 2% of the lowest capacity monomer. The equalization capacity difference is expected to be 20%. The equalization strategy at the end of charging for lithium iron phosphate batteries is to judge all monomers with voltage data greater than 3500mv. The equalization channel corresponding to the monomers with a voltage data greater than 20mv from the lowest voltage monomer is opened until the pressure difference from the lowest voltage monomer is less than 20mv.

[0101] For the static equalization strategy: the static state of the vehicle battery is judged, the vehicle satisfying the static state judgment is subjected to SOC-OCV lookup table calculation of the current SOC value of each single battery, and if the difference between the maximum SOC and the minimum SOC in the current SOC value corresponding to all single batteries is greater than 3%, the corresponding equalization channel of the single battery with a SOC greater than the average SOC is opened until the difference between the maximum SOC and the minimum SOC of the single battery is less than 1%.

[0102] S4, the multi-state equalization strategy is issued to the vehicle end BMS wireless communication module through the internal communication protocol, and the multi-state equalization strategy and the capacity difference of each single battery prepared by the cloud are transmitted to the vehicle end BMS through the downlink data format declared by the internal communication protocol. After the BMS receives, the cloud multi-state equalization strategy is implemented according to the state of the vehicle battery pack, the equalization channel of the corresponding single battery is opened, and the opening and closing of the equalization channel are automatically adjusted by the BMS according to the temperature and equalization capacity in the pack.

[0103] S5, according to the result of the last equalization strategy application, the next equalization strategy is optimized, the capacity difference of each single battery after the implementation of the cloud equalization strategy is obtained by analyzing the data performance of the BMS after the implementation of the cloud equalization strategy, and the capacity difference of each single battery before the implementation of the strategy is compared, the average value of the capacity difference change of each single battery after equalization is calculated, and the expected equalization capacity of the original single capacity difference is divided to obtain the equalization coefficient of the next equalization. When formulating the cloud equalization strategy next time, the expected equalization capacity is multiplied by the equalization coefficient to obtain the expected equalization capacity next time, and the cycle is repeated to continuously reduce the capacity difference.

[0104] Through the embodiment, the capacity difference between single batteries can be reduced, and problems such as accelerated battery aging caused by overcharging, overdischarging or long-term imbalance of single batteries can be avoided, so that the overall life of the battery pack is prolonged. By equalizing the state of each single battery, it can be ensured that the performance of each battery can be fully utilized during the charging and discharging process of the battery pack, and the output of the entire battery pack is limited by the performance of individual single batteries. Thus, the cruising range of new energy vehicles is improved, and problems such as thermal runaway caused by overcharging and overdischarging of batteries can also be prevented. In complex environments such as high temperature and high humidity, safety hazards caused by battery imbalance can also be reduced, and the safety of vehicles and passengers can be better protected.

[0105] As an optional embodiment, the cloud server receives the raw battery data transmitted from the vehicle-side BMS wireless transmission module, calculates the capacity differences of each single battery under multiple states of the vehicle according to the historical data of the vehicle, obtains the balancing capability of the vehicle through an internal communication protocol, formulates balancing strategies for different working conditions according to the capacity differences of each single battery, and issues the cloud balancing strategies to the vehicle-side BMS. The vehicle-side BMS implements the balancing strategies according to the current working condition of the vehicle battery pack, and finally the cloud adjusts the balancing strategies of the next time according to the implementation results of the last balancing strategies. In this way, through the collaborative work of the cloud server and the vehicle-side BMS, the vehicle can start the multi-state balancing under different working conditions, which brings many benefits. On the one hand, the multi-state balancing of the vehicle battery can avoid problems such as overcharging, over-discharging and local heating caused by too large capacity difference between battery monomers, effectively prolong the service life of the battery, reduce the replacement cost caused by battery aging, and improve the overall economy. On the other hand, the multi-state balancing can optimize the battery performance, make the battery pack play the best state in the charging and discharging process, improve the stability of the vehicle power output, ensure the continuous and stable output of power under complex working conditions such as high-speed driving, climbing and starting acceleration, and enhance the safety and comfort of driving, providing a more reliable driving experience for the driver.

[0106] According to the embodiments of the present application, an embodiment of a non-volatile storage medium is also provided. Optionally, in the present embodiment, the non-volatile storage medium includes a stored program, wherein the program controls the device in which the non-volatile storage medium is located to execute any of the vehicle battery balancing processing methods when the program is running.

[0107] Optionally, in the present embodiment, the non-volatile storage medium can be located in any one of the computer terminals in the computer terminal group in the computer network, or in any one of the mobile terminals in the mobile terminal group, and the non-volatile storage medium includes a stored program.

[0108] According to the embodiments of the present application, an embodiment of a processor is also provided. Optionally, in the present embodiment, the processor is used to run a program, wherein the program executes any of the vehicle battery balancing processing methods when the program is running.

[0109] According to the embodiments of the present application, an embodiment of a computer program product is also provided, which is adapted to execute the program that initializes the steps of any of the vehicle battery balancing processing methods when executed on a data processing device.

[0110] Optionally, the computer program product is adapted to execute the program that initializes the steps of any of the vehicle battery balancing processing methods when executed on a data processing device.

[0111] The electronic device includes a processor, a memory, and a program stored in the memory and executable on the processor, and the processor implements the program of the vehicle battery balancing processing method.

[0112] The sequence of the embodiments of the present application is only for description, and does not represent the advantages and disadvantages of the embodiments.

[0113] In the above embodiments of the present application, the description of each embodiment has its own emphasis, and the parts not described in detail in a certain embodiment can be referred to the related description of other embodiments.

[0114] In several embodiments provided in the present application, it should be understood that the disclosed technical contents can be implemented by other ways. Among them, the above-described device embodiments are only schematic, for example, the division of the above modules can be a logical function division, and actual implementation can have another division way, for example, a plurality of modules or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be through some interface, indirect coupling or communication connection between modules or modules, which can be electrical or other forms.

[0115] The above-described modules explained as separate components can or can not be physically separated, and the components displayed as modules can or can not be physical modules, that is, they can be located in one place, or can be distributed to multiple modules. According to actual needs, part or all of the modules can be selected to achieve the purpose of the present embodiment scheme.

[0116] In addition, each functional module in each embodiment of the present application can be integrated in one processing module, or each module can exist physically alone, or two or more modules can be integrated in one module. The above integrated module can be realized in the form of hardware or in the form of software functional module.

[0117] If the above-mentioned integrated modules are realized in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable nonvolatile storage medium. Based on this understanding, the technical solutions of the present application, essentially or the part that contributes to the prior art, or all or part of the technical solutions can be embodied in the form of a software product. The computer software product is stored in a non-volatile storage medium, including a number of instructions to make a computer device (which can be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the embodiments of the present application. The aforementioned non-volatile storage medium includes: a U disk, a read-only memory (ROM, Read-Only Memory), a random access memory (RAM, Random Access Memory), a mobile hard disk, a magnetic disk or an optical disk, and various media that can store program codes.

[0118] The above is only the preferred embodiment of the present application, and it should be pointed out that for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should be considered as the protection scope of the present application.

Claims

1. A vehicle battery equalization processing method characterized by, The method comprises: receiving historical battery data of a vehicle battery in a predetermined historical period; determining, based on the historical battery data, historical capacity differences of a plurality of single batteries included in the vehicle battery in a plurality of different operating states, wherein the plurality of different operating states include a static state and a constant current slow charging state; determining a multi-state equalization strategy of the vehicle battery, wherein the multi-state equalization strategy at least includes a discharging equalization strategy, a charging equalization strategy and a static equalization strategy; sending the multi-state equalization strategy and the historical capacity differences of the plurality of single batteries to a vehicle battery management system, for the vehicle battery management system to control the switching state of an equalization channel corresponding to each single battery, the equalization channel being used for capacity equalization of the single battery.

2. The method of claim 1, wherein, The method comprises: determining, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery in a plurality of different operating states, comprising: determining, based on the historical battery data, the historical capacity differences of the plurality of single batteries in the static state by the following method: identifying static battery data of the vehicle battery from the historical battery data, wherein the static battery data includes static voltage data of the plurality of single batteries, the static voltage data being the voltage of the corresponding single battery in the static state; obtaining static state of charge of the plurality of single batteries based on the static battery data, wherein the static state of charge is used to indicate the state of charge of the corresponding single battery in the static state; determining the maximum state of charge from the static state of charge of the plurality of single batteries; 3. The method of claim 2, wherein, performing difference operation on the static state of charge of the plurality of single batteries and the maximum state of charge to obtain the historical capacity differences of the plurality of single batteries in the static state. In the case that the vehicle battery is a lithium iron phosphate battery and the lithium iron phosphate battery is at the end of charging, the method comprises: determining a target single battery from the plurality of single batteries based on the static voltage data of the plurality of single batteries, wherein the target single battery is the single battery with the maximum static voltage data; detecting whether the static state of charge of the target single battery is less than a first preset state of charge; 4. The method of claim 1, wherein, in the case that the static state of charge of the target single battery is less than the first preset state of charge, obtaining the static state of charge of the plurality of single batteries based on the static battery data. The method comprises: determining, based on the historical battery data, the historical capacity differences of the plurality of single batteries included in the vehicle battery in a plurality of different operating states, comprising: determining, based on the historical battery data, the historical capacity differences of the plurality of single batteries in the constant current slow charging state by the following method: identify constant-current charging battery data of the vehicle battery from the historical battery data, wherein the constant-current charging battery data comprises constant-current charging voltage data corresponding to each of the plurality of single batteries, and the constant-current charging voltage data is the charging voltage of the corresponding single battery in the constant-current slow charging state; determine a constant-current charging time corresponding to each of the plurality of single batteries, wherein the constant-current charging time is the time when the constant-current charging voltage data of the corresponding single battery reaches a voltage reference value; determine the earliest time among the constant-current charging times corresponding to each of the plurality of single batteries; determine the time difference corresponding to each of the plurality of single batteries by performing difference operation on the constant-current charging time corresponding to each of the plurality of single batteries and the earliest time; based on the time difference corresponding to each of the plurality of single batteries and the constant-current value corresponding to the constant-current slow charging state, obtain the historical capacity difference corresponding to each of the plurality of single batteries in the constant-current slow charging state.

5. The method of claim 4, wherein, The method further comprises: in the case that the vehicle battery is a ternary battery, the voltage reference value is determined by determining a constant-current charging period corresponding to the constant-current slow charging state and a middle time in the constant-current charging period; determining the constant-current charging voltage data of the plurality of single batteries at the middle time; and determining the maximum value of the constant-current charging voltage data of the plurality of single batteries at the middle time as the voltage reference value; or in the case that the vehicle battery is a lithium iron phosphate battery, the voltage reference value is determined by determining a voltage curve corresponding to each of the plurality of single batteries, wherein the voltage curve represents the change process of the charging voltage of the single battery with time in the constant-current charging period; and determining the charging voltage corresponding to the maximum slope in the voltage curve corresponding to each of the plurality of single batteries as the voltage reference value.

6. A vehicle battery equalization processing method characterized by comprising: comprises: receiving historical capacity differences corresponding to each of a plurality of single batteries included in a vehicle battery in a plurality of different operating states and a multi-state equalization strategy of the vehicle battery sent by a cloud server, wherein the plurality of different operating states include a static state and a constant-current slow charging state; the historical capacity differences are obtained based on historical battery data of the vehicle battery within a predetermined historical period; and the multi-state equalization strategy at least includes a discharge equalization strategy, a charging equalization strategy and a static equalization strategy; based on the historical capacity differences corresponding to each of the plurality of single batteries and the multi-state equalization strategy, controlling the switching state of the equalization channel corresponding to each of the plurality of single batteries, wherein the equalization channel is used for capacity equalization of the single battery.

7. The method of claim 6, wherein, The control of the switching state of the equalization channel corresponding to each of the single batteries in the vehicle battery based on the historical capacity differences corresponding to each of the plurality of single batteries and the multi-state equalization strategy comprises: in the case that the vehicle battery is switched from the static state to the discharge state, the switching state of the equalization channel corresponding to each of the plurality of single batteries is controlled based on the discharge equalization strategy in the multi-state equalization strategy by: determine, based on the historical capacity differences of the plurality of single batteries respectively, current capacity differences of the plurality of single batteries respectively at the current time; identify a first single battery of the plurality of single batteries whose current capacity difference is greater than a preset first difference threshold, and control the opening of the equalization channel corresponding to the first single battery until the current capacity difference of the first single battery is less than the preset first difference threshold.

8. The method of claim 7, wherein, The method further comprises: determine, based on the historical capacity differences of the plurality of single batteries respectively, current capacity differences of the plurality of single batteries respectively at the current time; obtain the calculation capacity difference of the plurality of single batteries respectively at the current time, wherein the calculation capacity difference is obtained in the same way as the historical capacity difference; take the minimum value of the calculation capacity difference and the historical capacity difference of the plurality of single batteries respectively as the current capacity difference of the plurality of single batteries respectively; 9. The method of claim 6, wherein, In the case that the vehicle battery is a lithium iron phosphate battery and the lithium iron phosphate battery is in a voltage platform period, the historical capacity difference of the plurality of single batteries respectively in the static state is taken as the current capacity difference of the plurality of single batteries respectively. The method further comprises: based on the discharge equalization strategy in the multi-state equalization strategy, control the switching state of the equalization channel corresponding to the plurality of single batteries in the following way: In the case that it is detected that the vehicle battery is at the end of discharge, obtain the discharge voltage of the plurality of single batteries respectively, wherein the end of discharge is used to indicate that the vehicle battery is discharged to a preset first end-of-life state; determine the lowest discharge voltage among the discharge voltages of the plurality of single batteries respectively; 10. The method of claim 6, wherein, identify a second single battery of the plurality of single batteries whose difference between the discharge voltage and the lowest discharge voltage is greater than a first preset pressure difference threshold, and control the opening of the equalization channel corresponding to the second single battery until the difference between the discharge voltage and the lowest discharge voltage is less than the first preset pressure difference threshold. The method further comprises: In the case that it is detected that the vehicle battery is charged to a second preset state of charge, based on the charging equalization strategy in the multi-state equalization strategy, control the switching state of the equalization channel corresponding to the plurality of single batteries in the following way: In the case that the vehicle battery is a ternary battery, obtain the first charging voltage of the plurality of single batteries respectively, wherein the first charging voltage is the charging voltage of the single battery at the second preset state of charge; determine the lowest first charging voltage among the charging voltages of the plurality of single batteries respectively; identify a third single battery of the plurality of single batteries whose difference between the first charging voltage and the lowest first charging voltage is greater than a second preset pressure difference threshold, and control the opening of the equalization channel corresponding to the third single battery until the difference between the first charging voltage and the lowest first charging voltage is less than the second preset pressure difference threshold; In a case where the vehicle battery is a lithium iron phosphate battery, the historical capacity difference of each of the plurality of single batteries in the constant current slow charging state is taken as the current capacity difference of each of the plurality of single batteries; a fourth single battery with a current capacity difference greater than a preset second difference threshold is identified from the plurality of single batteries, and the opening of the equalization channel corresponding to the fourth single battery is controlled until the current capacity difference of the fourth single battery is less than the preset second difference threshold.

11. The method of claim 6, wherein, The method further comprises: In a case where it is detected that the vehicle battery is at a charging end, the charging end being used to indicate that the vehicle battery is charged to a preset second end-of-charge state, the switching state of the equalization channel corresponding to each of the plurality of single batteries is controlled based on the charging equalization strategy in the multi-state equalization strategy in the following manner: The second charging voltage corresponding to each of the plurality of single batteries is obtained, wherein the second charging voltage is the charging voltage of the single battery when the charging end is reached; the lowest second charging voltage is determined from the second charging voltage corresponding to each of the plurality of single batteries; a fifth single battery with a difference between the second charging voltage and the lowest second charging voltage greater than a third preset voltage difference threshold is identified from the plurality of single batteries, and the opening of the equalization channel corresponding to the fifth single battery is controlled until the difference between the second charging voltage and the lowest second charging voltage is less than the third preset voltage difference threshold.

12. The method of claim 6, wherein, The method further comprises: In a case where it is detected that the vehicle battery is in a stationary state, the switching state of the equalization channel corresponding to each of the plurality of single batteries is controlled based on the stationary equalization strategy in the multi-state equalization strategy in the following manner: The current state-of-charge of each of the plurality of single batteries in the stationary state is obtained; The maximum state-of-charge and the minimum state-of-charge of the current state-of-charge corresponding to each of the plurality of single batteries are identified; In a case where the difference between the maximum state-of-charge and the minimum state-of-charge is greater than a preset difference threshold, a sixth single battery with a current state-of-charge greater than an average state-of-charge is identified from the plurality of single batteries, wherein the average state-of-charge is the average of the current state-of-charge corresponding to each of the plurality of single batteries; The opening of the equalization channel corresponding to the sixth single battery is controlled until the current state-of-charge corresponding to the sixth single battery is less than the average state-of-charge.

13. An electronic device, comprising: One or more processors and a memory are included, and the memory is used to store one or more programs, wherein when the one or more programs are executed by the one or more processors, the one or more processors implement the vehicle battery equalization processing method of any one of claims 1 to 12.

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