Equalization control method and apparatus for power battery, vehicle, and storage medium

Abstract

The present application discloses an equalization control method and apparatus for a power battery, a vehicle, and a storage medium. The method comprises: determining, in a battery pack, battery cells to be equalized meeting an equalization enabling condition; determining, among the battery cells to be equalized, a target battery cell corresponding to the highest cell voltage; on the basis of the temperature of an equalization board area where the target battery cell is located and the position of the target battery cell in the battery pack, adjusting the number of the battery cells to be equalized to obtain a target battery cell to be equalized; and equalizing the target battery cell to be equalized.

Description

A power battery balancing control method, device, vehicle and storage medium

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202310753306.3, filed on June 25, 2023, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to the technical field of power battery balancing, and in particular to a power battery balancing control method, device, vehicle, and storage medium. Background Art

[0004] A power battery consists of multiple battery modules, each of which contains multiple groups of single cells. Due to differences in capacity, internal resistance, self-discharge rate, and charge / discharge efficiency among individual cells during use, inconsistent voltages can occur across the cells, shortening the battery's lifespan and battery life.

[0005] To protect the battery cells, they must be balanced. In related technologies, cell balancing is typically implemented using an odd-even balancing control algorithm. While this balancing method appears highly efficient, as all cells can be balanced, if too many cells require balancing, the temperature of the balancing board used to load the battery pack will rise significantly. Consequently, balancing must be disabled prematurely, effectively reducing overall balancing efficiency.

[0006] Summary of the Invention

[0007] The present disclosure provides a power battery balancing control method, device, vehicle, and storage medium to solve or partially solve the technical problem of low balancing efficiency during battery balancing in the prior art.

[0008] According to a first aspect of the present disclosure, a power battery balancing control method is provided, the method comprising: determining cells to be balanced in a battery pack that meet a balancing start condition; determining a target cell from the cells to be balanced, the target cell being the cell corresponding to the highest single cell voltage among the cells to be balanced; adjusting the number of cells to be balanced based on the temperature of a balancing plate region where the target cells are located and the position of the target cells in the battery pack to obtain target cells to be balanced; and balancing the target cells to be balanced.

[0009] According to a second aspect of the present disclosure, a power battery balancing control device is provided, the device comprising: a first determination unit for determining cells to be balanced in a battery pack that meet a balancing start condition; a second determination unit for determining a target cell from the cells to be balanced, the target cell being the cell corresponding to the highest single cell voltage among the cells to be balanced; an adjustment unit for adjusting the number of cells to be balanced based on the temperature of a balancing plate region where the target cells are located and the position of the target cells in the battery pack to obtain target cells to be balanced; and a balancing unit for balancing the target cells to be balanced.

[0010] According to a third aspect of the present disclosure, a vehicle is provided, comprising the power battery balancing control device according to any one of the second aspects.

[0011] According to a fourth aspect of the present disclosure, a computer-readable storage medium is provided, on which a computer program is stored. When the program is executed by a processor, the steps of the power battery balancing control method are implemented. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG1 shows a schematic diagram of a battery pack balancing circuit structure according to some embodiments of the present disclosure;

[0013] FIG2 shows a schematic flow chart of a power battery balancing control method according to some embodiments of the present disclosure; and

[0014] FIG3 shows a schematic structural diagram of a power battery balancing control device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0015] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0016] To better understand the technical solution of the present disclosure, let's first introduce the structure of the battery pack balancing circuit. As mentioned above, a battery pack contains multiple cells. A balancing board is installed in the battery pack, and the balancing board is mainly used to balance the voltage of the cells. However, due to the limited size of the balancing board (generally speaking, one balancing board can balance up to 12 cells), if the battery pack has a large number of cells, then multiple balancing boards are required.

[0017] The balancing board includes multiple balancing circuits, each balancing circuit corresponds to a battery cell. The balancing circuit is mainly used to balance the battery cells, and the structures of the balancing circuits are the same.

[0018] As shown in Figure 1, a balancing board 11 is used as an example. The balancing board 11 has n battery cells (BAT1 through BATn, where n can be 12). Taking cell BAT1 as an example, the balancing circuit for cell BAT1 consists of resistor R1 and MOS transistor Q1. The balancing board can consist of a battery sampling chip (AFE) and peripheral circuits. The AFE controls the on / off switching of each cell's balancing.

[0019] Since the essence of the balancing strategy in this disclosure is to dynamically adjust the number of cells to be balanced based on the temperature of the balancing board area where the target cell is located and the position of the target cell in the battery pack, referring to Figure 1, the balancing board of this disclosure is also equipped with a temperature sensor NTC (Negative Temperature Coefficient). Each temperature sensor NTC is used to collect the temperature of the balancing board area where four cells are located. If a balancing board is equipped with 12 cells, then three NTCs are required on the balancing board. The target cell is the cell with the highest single cell voltage among the cells to be balanced.

[0020] Based on the above-mentioned balancing control circuit, the present disclosure provides a power battery balancing control method, the implementation of which will be described in detail in the following embodiments. As shown in FIG2 , the power battery balancing control method mainly includes steps S210 to S213 .

[0021] In step S210 , cells to be balanced that meet a balancing start condition are determined in the battery pack.

[0022] In one embodiment, determining the battery cells to be balanced that meet the balancing start-up conditions includes: during the charging and discharging process (when the battery management system BMS is working), obtaining all effective cell voltages and the minimum effective cell voltage in the battery pack; traversing each of the effective cell voltages, and if the effective cell voltage is greater than a preset first voltage threshold and the voltage difference between the effective cell voltage and the minimum effective cell voltage is greater than a second voltage threshold, determining the battery cell corresponding to the effective cell voltage as the battery cell to be balanced that meets the balancing start-up conditions.

[0023] In one embodiment, obtaining all effective cell voltages in the battery pack includes: obtaining the voltage value of each cell; for any cell, if the voltage value of the cell is within the effective voltage range, determining the voltage value of the cell as the effective cell voltage.

[0024] A battery pack contains many cells, each with a unique location number within the pack. During charging, each cell in the pack will have a corresponding voltage, but some voltages are valid and some are invalid. In the disclosed embodiments, it is necessary to obtain the valid cell voltages of all cells in the pack.

[0025] In some embodiments, the effective voltage range is [2000mv, 4000mv]. For the voltage of any battery cell, the voltage that meets the effective voltage range is called the effective cell voltage; the voltage that exceeds the effective voltage range is called the invalid cell voltage.

[0026] In some embodiments, assuming that the voltage of a certain battery cell is 3000 mv, it indicates that the voltage of the battery cell is a valid single cell voltage; assuming that the voltage of a certain battery cell is 1500 mv or 4500 mv, it indicates that the voltage of the battery cell is an invalid single cell voltage.

[0027] After all valid cell voltages are obtained, the minimum valid cell voltage is determined from these, denoted as Vmin. All valid cell voltages are traversed. For any valid cell voltage Vi, if Vi > Vt and Vi - Vmin > ΔVt, the cell numbered i meets the equalization start-up condition. Vt is the first voltage threshold, and ΔVt is the second voltage threshold. The first and second voltage thresholds are pre-set based on the cell voltage characteristics and are not limited here.

[0028] In some embodiments, assuming that the voltage range of the battery cell is 2-4.4V, the first voltage threshold Vt may be 3.5-3.7V; the second voltage threshold ΔVt may be 0.02-0.04V, for example, ΔVt may be 0.03V.

[0029] Assume that the effective cell voltage Vi of a cell i is 3.7 V, the first voltage threshold is 3.5 V, the minimum effective cell voltage is 3.6 V, and the second voltage threshold is 0.02 V. Since Vi > 3.5 and Vi - Vmin > 0.02, cell i meets the balancing start condition and is to be balanced.

[0030] In this way, all cells to be balanced in the battery pack that meet the balancing start conditions can be determined. As mentioned above, each cell has a corresponding position number in the battery pack. After all cells to be balanced are determined, the position numbers of all cells to be balanced in the battery pack are obtained to determine the corresponding sequence of cells to be balanced.

[0031] In some embodiments, it is assumed that the cells to be balanced in the battery pack are: A1, A3, A6, A9, A11, A12, A15, A16, A18, A20, A23;

[0032] The positions of these cells to be balanced in the battery pack are numbered: b1, b3, b6, b9, b11, b12, b15, b16, b18, b20, b23.

[0033] Then the sequence of cells to be balanced can be (b1, b3, b6, b9, b11, b12, b15, b16, b18, b20, b23).

[0034] In some embodiments, a sequence of cells to be balanced is determined, and when the number of cells to be balanced is subsequently dynamically adjusted, auxiliary judgment can be made based on the sequence of cells to be balanced, thereby improving the balancing rate.

[0035] In step S211 , a target cell is determined from the cells to be balanced, where the target cell is the cell corresponding to the highest cell voltage among the cells to be balanced.

[0036] After the cells to be balanced are determined, the target cell needs to be determined from the cells to be balanced. The target cell is the cell to be balanced corresponding to the highest cell voltage among the cells to be balanced. For example, among the cells to be balanced, assuming that cell A11 has the highest voltage, then cell A11 is the target cell.

[0037] In step S212 , the number of cells to be balanced is adjusted based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack to obtain the target cell to be balanced.

[0038] As mentioned above, if the number of cells to be balanced is large, the existing odd-even balancing control algorithm will cause the temperature of the balancing board used to load the battery pack to rise very high, and sometimes the balancing has to be turned off early, resulting in reduced balancing efficiency.

[0039] The key to improving balancing efficiency in this disclosure is to maintain the consistency of the voltage of each cell in the shortest possible time within the allowable range of the balancing board temperature rise. Therefore, the control goal of this disclosure is to control the target cell corresponding to the highest single cell voltage to always be balanced at maximum efficiency throughout the entire process. To prevent the balancing algorithm from being shut down prematurely, it is necessary to dynamically monitor the temperature of the balancing board area where the target cell is located. Based on this temperature and the position of the target cell, the number of cells to be balanced around the target cell is dynamically adjusted to ensure that the balancing board temperature rise can be within the allowable range. This will reduce the voltage of the target cell as quickly as possible, thereby improving balancing efficiency.

[0040] It should be noted that when the temperature of the balancing board area where the target cell is located is different, the corresponding balancing strategy is also different. The temperature of the balancing board area where the target cell is located can be collected using a corresponding temperature sensor.

[0041] In one embodiment, adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack includes:

[0042] Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced;

[0043] Grouping the position numbers of all cells installed on the target balancing board based on the temperature sensor numbers and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group; the target balancing board is the balancing board where the target cell is located;

[0044] If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group;

[0045] If it is determined that the current sequence number is the first sequence number and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, turning off balancing of the cell corresponding to the fourth sequence number in the target cell group;

[0046] If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, balancing of the cell corresponding to the first sequence number in the target cell group is turned off.

[0047] As can be seen above, in some embodiments, a balancing board can only accommodate 12 battery cells. Three temperature sensors are installed on a balancing board, with one temperature sensor corresponding to four battery cells. To accurately adjust the number of cells to be balanced, the cells on any balancing board must be grouped by their position numbers based on the temperature sensor numbers.

[0048] Taking a balancing board with cells A1 to A12 installed as an example, the first temperature sensor on the balancing board corresponds to cells A1 to A4, so the positions of the cells corresponding to the first temperature sensor are numbered (b1 to b4); the second temperature sensor corresponds to cells A5 to A8, so the positions of the cells corresponding to the second temperature sensor are numbered (b5 to b8); the third temperature sensor corresponds to cells A9 to A12, so the positions of the cells corresponding to the second temperature sensor are numbered (b9 to b12).

[0049] The present disclosure determines the position of the target cell in the battery pack, mainly determining the position of the target cell in the target cell group, and setting the current sequence number of the target cell in the target cell group to bmax. Assuming that the target cell is A11, the target cell group is the third cell group. If the target cell is A11, the target cell group actually includes four cells A9 to A12, A9 is the cell with the first sequence number in the target cell group, A10 is the cell with the second sequence number in the target cell group, and A11 is the cell with the third sequence number in the target cell group, that is, the current sequence number of the target cell in the target cell group is 3, then bmax=3; A12 is the cell with the fourth sequence number in the target cell group.

[0050] Since the target cell belongs to the third cell group, the temperature of the balancing board area where the target cell is located is the temperature collected by the third temperature sensor. If the temperature of the balancing board area where the target cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, and bmax = 1, determine whether the cell corresponding to bmax+3 is in the sequence of cells to be balanced. If so, disable balancing for the cell with sequence number bmax+3.

[0051] It should be noted that if the cell corresponding to bmax+3 is not in the sequence of cells to be balanced, no action needs to be performed.

[0052] In some embodiments, assuming that A9 in the third cell group is the target cell, bmax=1, if A12 is in the sequence of cells to be balanced, balancing of cell A12 is disabled; if A12 is not in the sequence of cells to be balanced, no action is performed.

[0053] If the temperature of the balancing board region where the target cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, and bmax=2, balancing of any cell in the cell group is not disabled.

[0054] If the temperature of the balancing board region where the target cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, and bmax=3, balancing of any cell in the cell group is not disabled.

[0055] If the temperature of the balancing board area where the target cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, and bmax=4, determine whether the bmax-3 cell is in the sequence of cells to be balanced. If so, turn off balancing for the cell with sequence number bmax-3.

[0056] In some embodiments, assuming that A12 in the third cell group is the target cell, bmax=4, if A9 is in the sequence of cells to be balanced, balancing of cell A9 is disabled; if A9 is not in the sequence of cells to be balanced, no action is performed.

[0057] In some embodiments, the first temperature threshold may be Tthreshold-6°C, and the second temperature threshold may be Tthreshold-4°C; Tthreshold is a preset fourth temperature threshold, and the value range may be 80-90°C, for example, Tthreshold is 85°C.

[0058] In one embodiment, adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack includes:

[0059] Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced;

[0060] Grouping the position numbers of all cells installed on the target balancing board based on the temperature sensor numbers, and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group;

[0061] If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group;

[0062] If it is determined that the current sequence number is the first sequence number and it is determined that the cell corresponding to the third sequence number in the target cell group is in the sequence of cells to be balanced, disabling balancing of the cell corresponding to the third sequence number in the target cell group;

[0063] If it is determined that the current sequence number is the second sequence number, and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, disabling balancing of the cell corresponding to the fourth sequence number in the target cell group;

[0064] If it is determined that the current sequence number is the third sequence number and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, disabling balancing of the cell corresponding to the first sequence number in the target cell group;

[0065] If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, balancing of the cell corresponding to the second sequence number in the target cell group is disabled.

[0066] The specific implementation of determining the sequence of cells to be balanced, grouping the position numbers of all cells installed on the target balancing board, and determining the target cell group where the target cell is located can be referred to the above description, so it will not be repeated here.

[0067] In some embodiments, if the temperature of the balancing board area where the target battery cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, and bmax=1, it is determined whether the bmax+2 battery cell is in the sequence of batteries to be balanced. If so, the balancing of the battery cell with sequence number bmax+2 is turned off.

[0068] In some embodiments, assuming that A9 in the third cell group is the target cell, bmax=1, if A11 is in the sequence of cells to be balanced, balancing of cell A11 is disabled; if A11 is not in the sequence of cells to be balanced, no action is performed.

[0069] If the temperature of the balancing board area where the target cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, and bmax=2, determine whether the bmax+2 cell is in the sequence of cells to be balanced. If so, disable balancing for the cell with sequence number bmax+2.

[0070] In some embodiments, assuming that A10 in the third cell group is the target cell, bmax=2, if A12 is in the sequence of cells to be balanced, balancing of cell A12 is disabled; if A12 is not in the sequence of cells to be balanced, no action is performed.

[0071] If the temperature of the balancing board area where the target cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, and bmax=3, determine whether the bmax-2 cell is in the sequence of cells to be balanced. If so, turn off balancing for the cell with sequence number bmax-2.

[0072] In some embodiments, assuming that A11 in the third cell group is the target cell, bmax=3, if A9 is in the sequence of cells to be balanced, balancing of cell A9 is disabled; if A9 is not in the sequence of cells to be balanced, no action is performed.

[0073] If the temperature of the balancing board area where the target cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, and bmax=4, determine whether the bmax-2 cell is in the sequence of cells to be balanced. If so, turn off balancing for the cell with sequence number bmax-2.

[0074] In some embodiments, assuming that A12 in the third cell group is the target cell, bmax=4, if A10 is in the sequence of cells to be balanced, balancing of cell A10 is disabled; if A10 is not in the sequence of cells to be balanced, no action is performed.

[0075] In some embodiments, the third temperature threshold may be Tthreshold-2°C, Tthreshold is a preset fourth temperature threshold, and the value range may be 80-90°C, for example, Tthreshold is 85°C.

[0076] In one embodiment, adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack includes:

[0077] Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced;

[0078] Grouping the position numbers of all cells installed on the target balancing board based on the temperature sensor numbers, and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group;

[0079] If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group;

[0080] If it is determined that the current sequence number is the first sequence number and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, disabling balancing of the cell corresponding to the second sequence number in the target cell group;

[0081] If it is determined that the current sequence number is the second sequence number, and it is determined that the cell corresponding to the first sequence number and the cell corresponding to the second sequence number in the target cell group are in the sequence of cells to be balanced, disabling balancing of the cells corresponding to the first sequence number and the second sequence number in the target cell group;

[0082] If it is determined that the current sequence number is the third sequence number, and it is determined that the cell corresponding to the second sequence number and the cell corresponding to the fourth sequence number in the target cell group are in the sequence of cells to be balanced, disabling balancing of the cells corresponding to the second sequence number and the fourth sequence number in the target cell group;

[0083] If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, balancing of the cell corresponding to the second sequence number in the target cell group is disabled.

[0084] The specific implementation of determining the sequence of cells to be balanced, grouping the position numbers of all cells installed on the target balancing board, and determining the target cell group where the target cell is located can be referred to the above description and will not be repeated here.

[0085] In some embodiments, if the temperature of the balancing board area where the target battery cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, and bmax=1, it is determined whether the bmax+1 battery cell is in the sequence of batteries to be balanced. If so, the balancing of the battery cell with sequence number bmax+1 is turned off.

[0086] In some embodiments, assuming that A9 in the third cell group is the target cell, bmax=1, if A10 is in the sequence of cells to be balanced, balancing of cell A10 is disabled; if A10 is not in the sequence of cells to be balanced, no action is performed.

[0087] If the temperature of the balancing board area where the target battery cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, and bmax=2, determine whether the bmax+1 battery cell and the bmax-1 battery cell are in the sequence of batteries to be balanced. If the bmax+1 battery cell and the bmax-1 battery cell are both in the sequence of batteries to be balanced, then disable balancing of the battery cell with sequence number bmax+1 and bmax-1.

[0088] In some embodiments, assuming that A10 in the third cell group is the target cell, and bmax = 2, if A9 is in the sequence of cells to be balanced and A11 is not, balancing for cell A9 is disabled and no action is taken on A11. If A9 is also not in the sequence of cells to be balanced, no action is taken on A9. If both A9 and A11 are in the sequence of cells to be balanced, balancing for both cells is disabled.

[0089] If the temperature of the balancing board area where the target cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, and bmax=3, determine whether the bmax+1 cell and the bmax-1 cell are in the sequence of cells to be balanced. If both are, then disable balancing for the cells with sequence numbers bmax+1 and bmax-1.

[0090] In some embodiments, assuming that A11 in the third cell group is the target cell, bmax=3, if A12 is in the sequence of cells to be balanced and A10 is not in the sequence of cells to be balanced, balancing of cell A12 is turned off and no action is performed on A10; if A12 is not in the sequence of cells to be balanced either, no action is performed on A12.

[0091] If the temperature of the balancing board area where the target cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, and bmax=4, determine whether the bmax-1 cell is in the sequence of cells to be balanced. If so, disable balancing for the cell with sequence number bmax-1.

[0092] In some embodiments, assuming that A12 in the third cell group is the target cell, bmax=4, if A12 is in the sequence of cells to be balanced, balancing of cell A11 is disabled; if A11 is not in the sequence of cells to be balanced, no action is performed.

[0093] In one embodiment, adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack includes:

[0094] If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than a fourth temperature threshold, balancing of the target battery cell is turned off.

[0095] In some embodiments, if the temperature of the balancing board region where the target battery cell is located is greater than or equal to a fourth temperature threshold, balancing of the target battery cell is directly turned off to prevent the battery cell from being damaged.

[0096] The fourth temperature threshold is Tthreshold, which may range from 80°C to 90°C. In some embodiments, Tthreshold is 85°C.

[0097] In this way, the number of cells to be balanced can be dynamically adjusted in real time according to the temperature of the balancing board area where the target cell is located and the position of the target cell, and the target cell to be balanced that ultimately needs to be balanced is determined. By reducing the number of cells to be balanced around the target cell with the highest single cell voltage, the temperature rise of the balancing board area where the target cell is located can be reduced, thereby reducing the voltage of the target cell in the shortest time. By continuously executing the above strategy, from a time dimension, the consistency of the voltage of each cell can be maintained as quickly as possible.

[0098] Step S213: balancing the target battery cell to be balanced.

[0099] After the target cells to be balanced are determined, the target cells to be balanced can be balanced using a preset balancing strategy.

[0100] It should be noted that during the charge and discharge process of the battery pack, the voltage of each cell is constantly changing. To improve the accuracy of balancing, the balancing control method provided by this disclosure needs to be executed cyclically. For example, after balancing is completed for some cells to be balanced for the first time, steps S210 to S213 need to be executed a second time until all cells to be balanced are completely balanced. The interval between the two executions can be 10ms, that is, steps S210 to S213 need to be executed once every 10ms.

[0101] Based on the same inventive concept as in the aforementioned embodiment, the present disclosure further provides a power battery balancing control device, as shown in FIG3 , the device includes:

[0102] The first determining unit 31 is configured to determine cells to be balanced that meet a balancing start condition in the battery pack;

[0103] A second determining unit 32 is configured to determine a target cell from the cells to be balanced, where the target cell is a cell corresponding to the highest cell voltage among the cells to be balanced;

[0104] an adjusting unit 33, configured to adjust the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack to obtain a target cell to be balanced; and

[0105] The balancing unit 34 is configured to balance the target battery cells to be balanced.

[0106] In one embodiment, the first determining unit 31 is configured to:

[0107] During the charge and discharge process, obtain the effective cell voltages of all cells in the battery pack and the minimum effective cell voltage; and

[0108] Traversing each of the effective cell voltages, if the effective cell voltage is greater than a preset first voltage threshold and the voltage difference between the effective cell voltage and the minimum effective cell voltage is greater than a second voltage threshold, the cell corresponding to the effective cell voltage is determined as the cell to be balanced that meets the balancing start condition for the first time.

[0109] In one embodiment, the adjustment unit 33 is configured to:

[0110] Grouping the position numbers of the battery cells based on the temperature sensor numbers, and determining the target battery cell group where the target battery cell is located; one temperature sensor corresponds to one battery cell group;

[0111] Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced;

[0112] If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group;

[0113] If it is determined that the current sequence number is the first sequence number, and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, disabling balancing of the cell corresponding to the fourth sequence number in the target cell group; and

[0114] If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, balancing of the cell corresponding to the first sequence number in the target cell group is disabled.

[0115] Since the device described in the embodiments of this disclosure is a power battery balancing control device that implements the embodiments of this disclosure, the specific structure and variations of the device are readily understood by those skilled in the art based on the methods described in the embodiments of this disclosure, and therefore will not be described in detail here. All devices used in the methods of the embodiments of this disclosure fall within the scope of protection intended by this disclosure.

[0116] Based on the same inventive concept as the aforementioned embodiment, the present disclosure further provides a vehicle including the aforementioned power battery balancing control device. The overall structure and specific balancing strategy of the power battery balancing control device can be found in the above description and will not be further elaborated here.

[0117] The present disclosure also provides a computer program product or computer program, which includes computer instructions stored in a computer-readable storage medium. A processor of a computer device reads the computer instructions from the computer-readable storage medium and executes the computer instructions, causing the computer device to perform the power battery balancing control method described in the above embodiments.

[0118] The present disclosure also provides a computer-readable medium, which may be included in the electronic device described in the above embodiments, or may exist independently and not be incorporated into the electronic device. The computer-readable medium carries one or more programs, and when executed by the electronic device, the electronic device implements the power battery balancing control method described in the above embodiments.

[0119] It should be noted that although several modules or units of the device for action execution are mentioned in the detailed description above, this division is not mandatory. In fact, according to the embodiments of the present disclosure, the features and functions of two or more modules or units described above can be concretized in one module or unit. Conversely, the features and functions of one module or unit described above can be further divided into multiple modules or units to be concretized.

[0120] Through the description of the above embodiments, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution of the present disclosure can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, USB flash drive, mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, server, touch terminal, or network device, etc.) to execute the power battery balancing control method provided by the present disclosure.

[0121] Through one or more embodiments of the present disclosure, the present disclosure has the following beneficial effects or advantages:

[0122] The present disclosure provides a power battery balancing control method, device, vehicle and storage medium, the method comprising: determining cells to be balanced in a battery pack that meet the balancing start-up conditions; determining a target cell from the cells to be balanced, the target cell being the cell corresponding to the highest cell voltage among the cells to be balanced; adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cell is located and the position of the target cell in the battery pack to obtain a target cell to be balanced; and balancing the target cell to be balanced. In the above scheme, when the number of cells to be balanced is large, the number of cells to be balanced can be dynamically adjusted based on the temperature of the balancing plate region where the cell corresponding to the highest cell voltage is located, thereby reducing the temperature rise of the balancing plate region where the target cell is located, reducing the voltage of the target cell in the shortest time within the range allowed by the balancing plate temperature where the target cell is located, and measuring from the time dimension, it can maintain the consistency of the voltage of each cell as quickly as possible, thereby improving the balancing rate of the cells to be balanced.

[0123] Although some embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the above embodiments and all changes and modifications that fall within the scope of the present disclosure.

[0124] The above description is merely a preferred embodiment of the present disclosure and is not intended to limit the scope of protection of the present disclosure. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present disclosure shall be included in the scope of protection of the present disclosure.

Claims

1. A power battery balancing control method, comprising: Determine the cells to be balanced in the battery pack that meet the balancing start condition; Determine a target cell from the cells to be balanced, the target cell being a cell corresponding to the highest cell voltage among the cells to be balanced; Adjusting the number of cells to be balanced based on the temperature of the balancing plate region where the target cells are located and the position of the target cells in the battery pack to obtain target cells to be balanced; and The target battery cell to be balanced is balanced.

2. The method of claim 1, wherein: The step of determining the cells to be balanced that meet the balancing start condition in the battery pack includes: During the charging and discharging process, all effective cell voltages and the minimum effective cell voltage in the battery pack are obtained; and Traversing each of the effective cell voltages, if the effective cell voltage is greater than a preset first voltage threshold and the voltage difference between the effective cell voltage and the minimum effective cell voltage is greater than a second voltage threshold, the cell corresponding to the effective cell voltage is determined as a cell to be balanced that meets the balancing start condition.

3. The method of claim 1, wherein: The adjusting the number of the cells to be balanced based on the temperature of the balancing board area where the target cells are located and the position of the target cells in the battery pack includes: Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced; Grouping the position numbers of all the cells installed on the target balancing board based on the temperature sensor numbers, and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group; If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group; If it is determined that the current sequence number is the first sequence number, and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, turning off the balancing of the cell corresponding to the fourth sequence number in the target cell group; and If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, the balancing of the cell corresponding to the first sequence number in the target cell group is turned off.

4. The method of claim 1, wherein: The adjusting the number of the cells to be balanced based on the temperature of the balancing board area where the target cells are located and the position of the target cells in the battery pack includes: Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced; Grouping the position numbers of all the cells installed on the target balancing board based on the temperature sensor numbers, and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group; If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the second temperature threshold and less than the third temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group; If it is determined that the current sequence number is the first sequence number, and it is determined that the cell corresponding to the third sequence number in the target cell group is in the sequence of cells to be balanced, turning off the balancing of the cell corresponding to the third sequence number in the target cell group; If it is determined that the current sequence number is the second sequence number, and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, closing the balancing of the cell corresponding to the fourth sequence number in the target cell group; If it is determined that the current sequence number is the third sequence number, and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, turning off the balancing of the cell corresponding to the first sequence number in the target cell group; and If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, the balancing of the cell corresponding to the second sequence number in the target cell group is turned off.

5. The method of claim 1, wherein: The adjusting the number of the cells to be balanced based on the temperature of the balancing board area where the target cells are located and the position of the target cells in the battery pack includes: Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced; Grouping the position numbers of all the cells installed on the target balancing board based on the temperature sensor numbers, and determining the target cell group where the target cell is located; one temperature sensor corresponds to one cell group; If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the third temperature threshold and less than the fourth temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group; If it is determined that the current sequence number is the first sequence number, and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, closing the balancing of the cell corresponding to the second sequence number in the target cell group; If it is determined that the current sequence number is the second sequence number, and it is determined that the cell corresponding to the first sequence number and the cell corresponding to the second sequence number in the target cell group are in the sequence of cells to be balanced, closing the balancing of the cells corresponding to the first sequence number and the second sequence number in the target cell group; If it is determined that the current sequence number is the third sequence number, and it is determined that the cell corresponding to the second sequence number and the cell corresponding to the fourth sequence number in the target cell group are in the sequence of cells to be balanced, turning off the balancing of the cells corresponding to the second sequence number and the fourth sequence number in the target cell group; and If it is determined that the current sequence number is the fourth sequence number, and it is determined that the cell corresponding to the second sequence number in the target cell group is in the sequence of cells to be balanced, close the second sequence number in the target cell group. Balance of the cells.

6. The method of claim 1, wherein: The adjusting the number of the cells to be balanced based on the temperature of the balancing board area where the target cells are located and the position of the target cells in the battery pack includes: If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than a fourth temperature threshold, the balancing of the target battery cell is turned off.

7. A power battery balancing control device, comprising: A first determining unit, used to determine the battery cells to be balanced that meet the balancing start condition in the battery pack; A second determining unit is used to determine a target cell from the cells to be balanced, wherein the target cell is a cell corresponding to the highest cell voltage among the cells to be balanced; an adjusting unit, configured to adjust the number of the cells to be balanced based on the temperature of the balancing plate region where the target cells are located and the position of the target cells in the battery pack to obtain target cells to be balanced; and The balancing unit is used to balance the target battery cell to be balanced.

8. The device according to claim 7, wherein: The first determining unit is used for: During the charging and discharging process, all effective cell voltages and the minimum effective cell voltage in the battery pack are obtained; and Traversing each of the effective cell voltages, if the effective cell voltage is greater than a preset first voltage threshold and the voltage difference between the effective cell voltage and the minimum effective cell voltage is greater than a second voltage threshold, the cell corresponding to the effective cell voltage is determined as the cell to be balanced that first meets the balancing start condition.

9. The device according to claim 7, wherein: The adjustment unit is used for: The position numbers of the battery cells are grouped based on the temperature sensor numbers, and the target battery cell group where the target battery cell is located is determined; one temperature sensor corresponds to one battery cell group; Obtain the position numbers of all cells to be balanced in the battery pack to determine the sequence of cells to be balanced; If it is determined that the temperature of the balancing board region where the target battery cell is located is greater than or equal to the first temperature threshold and less than the second temperature threshold, obtaining the current sequence number of the target battery cell in the target battery cell group; If it is determined that the current sequence number is the first sequence number, and it is determined that the cell corresponding to the fourth sequence number in the target cell group is in the sequence of cells to be balanced, turning off the balancing of the cell corresponding to the fourth sequence number in the target cell group; and If it is determined that the current sequence number is the fourth sequence number and it is determined that the cell corresponding to the first sequence number in the target cell group is in the sequence of cells to be balanced, the balancing of the cell corresponding to the first sequence number in the target cell group is turned off.

10. A vehicle, comprising the power battery balancing control device according to any one of claims 7 to 9.

11. A computer-readable storage medium having a computer program stored thereon, wherein when the program is executed by a processor, the steps of the method according to any one of claims 1 to 6 are implemented.

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