WO-2026092399-A1 - BATTERY EQUALIZATION PROCESSING METHOD AND APPARATUS, AND ELECTRONIC DEVICE AND STORAGE MEDIUM

WO2026092399A1WO 2026092399 A1WO2026092399 A1WO 2026092399A1WO-2026092399-A1

Abstract

A battery equalization processing method and apparatus, and an electronic device and a storage medium. The method comprises: determining a full-discharge capacity difference between each battery cell and the battery cell having the lowest full-discharge capacity in a fully discharged state; determining a full-charge capacity difference between each battery cell and the battery cell having the highest full-charge capacity in a fully charged state; determining the total capacity of each battery cell from the fully discharged state to the fully charged state; determining the current total capacity of each battery cell in the fully charged state; and on the basis of the total capacity of each battery cell, the current total capacity of each battery cell, and each full-charge capacity difference, determining an equalization amount of each battery cell, and on the basis of the equalization amount of each battery cell, performing charge/discharge equalization on each battery cell. By means of an association relationship between voltage characteristics and capacity, full-discharge capacity differences and full-charge capacity differences that are determined are more reasonable, such that a determined equalization amount of each battery cell is more accurate, thereby achieving a better equalization effect for each battery cell.

Inventors

PAN, Binbiao
LI, Jianjie
LIN, HAIJUN

Assignees

欣捷安汽车电子有限公司

Dates

Publication Date: 20260507
Application Date: 20251027
Priority Date: 20241028

Claims (15)

A battery equalization processing method, wherein the method is used to perform charge-discharge equalization on each individual cell in a battery pack, the method comprising: Based on the target discharge voltage of each individual cell in the venting state, the first mapping relationship between voltage and capacity during the discharge process, and the discharge capacity difference between the total discharge capacity of the battery pack in the venting state and the final total discharge capacity during the discharge process, the discharge capacity difference between each individual cell and the individual cell with the lowest discharge capacity in the venting state is determined; wherein, the target discharge voltage is obtained by correcting the actual discharge voltage of the individual cell in the venting state, and the individual cell with the lowest discharge capacity is the individual cell with the lowest actual discharge voltage in the venting state. Based on the target charging voltage of each individual cell when fully charged, the second mapping relationship between voltage and capacity during the charging process, and the difference in charging capacity between the total charging capacity of the battery pack when fully charged and the final total charging capacity during the charging process, the full-charge capacity difference between each individual cell and the cell with the highest full charge when fully charged is determined; wherein, the target charging voltage is obtained by correcting the actual charging voltage of the individual cell when fully charged, and the cell with the highest full charge is the individual cell with the highest actual charging voltage when fully charged; The total capacity of each individual cell from the vented state to the fully charged state is determined based on the vented capacity difference, the fully charged capacity difference, and the total capacity of the battery pack. Based on the difference in venting capacity of each individual cell and the total capacity of the battery pack, determine the current total capacity of each individual cell when fully charged. Based on the total capacity of each individual battery cell, the current total capacity of each individual battery cell, and the difference in fully charged capacity of each individual battery cell, the equalization amount of each individual battery cell is determined, and the charge and discharge equalization of each individual battery cell is performed based on the equalization amount of each individual battery cell.
According to the battery equalization processing method of claim 1, the step of determining the discharge capacity difference between each individual cell and the cell with the lowest discharge capacity in the discharge state, based on the target discharge voltage of each individual cell in the discharge state, the first mapping relationship between voltage and capacity during the discharge process, and the discharge capacity difference between the total discharge capacity of the battery pack in the discharge state and the final total discharge capacity during the discharge process, includes: Determine the actual discharge voltage before correction to the target discharge voltage based on the target discharge voltage; Based on the first mapping relationship between voltage and capacity during the discharge process, the discharge capacity corresponding to the actual discharge voltage is determined, and the discharge capacity is used as the first target capacity corresponding to the target discharge voltage. The sum of the difference between the first target capacity and the discharge capacity is taken as the venting capacity difference.
According to the battery equalization processing method of claim 2, the step of determining the charging capacity difference between each individual cell and the highest-charged cell in the fully charged state, based on the target charging voltage of each individual cell in the fully charged state, the second mapping relationship between voltage and capacity during the charging process, and the charging capacity difference between the total charging capacity of the battery pack in the fully charged state and the final total charging capacity during the charging process, includes: Determine the actual charging voltage before correction to the target charging voltage based on the target charging voltage; Based on the second mapping relationship between voltage and capacity during the charging process, the charging capacity corresponding to the actual charging voltage is determined, and the charging capacity is used as the second target capacity corresponding to the target charging voltage. The sum of the difference between the second target capacity and the charging capacity is taken as the full charge capacity difference.
According to the battery equalization processing method of claim 1, the first mapping relationship between voltage and capacity during the discharge process is determined through the following steps: During the discharge process of the battery pack, the first total discharge capacity of the battery pack and its corresponding first minimum single cell voltage are obtained at preset capacity change intervals. When the battery pack is in a discharged state, the total discharge capacity of the battery pack and its corresponding minimum single cell voltage are obtained. Based on the first total discharge capacity and its corresponding first minimum single cell voltage, and the total discharge capacity and its corresponding minimum single cell voltage, a first mapping relationship between voltage and capacity during the discharge process is determined.
According to the battery equalization processing method of claim 1, the second mapping relationship between voltage and capacity during the charging process is determined through the following steps: During the charging process of the battery pack, the second total charging capacity of the battery pack and its corresponding second highest single cell voltage are obtained at preset capacity change intervals; when the battery pack is fully charged, the total charging capacity of the battery pack and its corresponding highest single cell voltage are obtained. Based on each second total charging capacity and its corresponding second highest single cell voltage, and the total charging capacity and its corresponding highest single cell voltage, a second mapping relationship between voltage and capacity is determined during the charging process.
According to the battery equalization processing method of claim 4, the target discharge voltage is obtained by correcting the actual discharge voltage of the single cell in the vented state, including: Determine the actual discharge voltage of the single cell when it is in a discharged state, the first voltage change of the single cell under preset conditions, and the second voltage change of the single cell with the lowest discharge. Calculate the difference between the first voltage change and the second voltage change; The difference between the actual single-cell voltage of the single cell and the difference between the first voltage change is taken as the target discharge voltage of the single cell.
According to the battery equalization processing method of claim 5, the target charging voltage is obtained by correcting the actual charging voltage of the single cell when it is fully charged, including: The actual charging voltage of the single cell when it is fully charged, the third voltage change of the single cell under preset conditions, and the fourth voltage change of the single cell with the highest charge are determined. Calculate the difference between the third voltage change and the fourth voltage change; The sum of the difference between the actual single-cell voltage and the second voltage change is taken as the target charging voltage of the single-cell battery.
According to the battery equalization processing method of claim 4, the final total discharge capacity during the discharge process is the last first total discharge capacity of the battery pack obtained by the preset capacity change amount at the interval. The final total charging capacity during the charging process is the last second total charging capacity of the battery pack obtained by the preset capacity change amount at the interval.
According to the battery equalization processing method of claim 1, the total capacity of each individual battery is the sum of the total capacity of the battery pack, the difference in fully charged capacity of each individual battery, and the difference in discharged capacity of each individual battery. The current total capacity of each individual battery cell is the sum of the differences between the total capacity of the battery pack and the discharge capacity of each individual battery cell.
According to the battery balancing method of claim 1, the step of determining the balancing amount of each individual battery based on the total capacity of each individual battery, the current total capacity of each individual battery, and the difference in fully charged capacity of each individual battery includes: Determine the minimum total capacity from the total capacity of each of the individual cells and determine the minimum current total capacity from the current total capacity of each of the individual cells; Calculate the capacity difference between the minimum total capacity and the minimum current total capacity; The difference between the capacity difference and the full-charge capacity difference corresponding to the individual cell is used as the equalization amount of the individual cell.
According to the battery equalization processing method of claim 1, the discharge capacity difference is calculated by the following formula: Array1_dVmin_Cap=0.1×LookUpTable(Array1_minV, Index_Array_minV, Array1_CellV^')+dCap1_dch; Wherein, Array1_dVmin_Cap is the discharge capacity difference, Array1_minV is an array including the first minimum single cell voltage corresponding to the first total discharge capacity of each battery pack at preset capacity changes, Index_Array_minV is the index number corresponding to each first minimum single cell voltage in the array, and dCap1_dch is the discharge capacity difference.
According to the battery equalization processing method of claim 1, the difference in fully charged capacity is calculated by the following formula; Array2_dVmax_Cap=0.1×LookUpTable(Array2_maxV, Index_Array_maxV, Array2_CellV^')+dCap2_dch; Wherein, Array2_maxV is an array containing the second highest single cell voltage corresponding to each second total charging capacity of the battery pack at preset capacity changes, Index_Array_maxV is the index number corresponding to each second highest single cell voltage, and dCap2_dch is the charging capacity difference.
A battery equalization processing device, comprising: The discharge determination module is configured to determine the discharge capacity difference between each individual cell and the cell with the lowest discharge capacity in the discharge state, based on the target discharge voltage of each individual cell in the discharge state, the first mapping relationship between voltage and capacity during the discharge process, and the discharge capacity difference between the total discharge capacity of the battery pack in the discharge state and the final total discharge capacity during the discharge process; wherein, the target discharge voltage is obtained by correcting the actual discharge voltage of the individual cell in the discharge state, and the cell with the lowest discharge capacity is the individual cell with the lowest actual discharge voltage in the discharge state; The charging determination module is configured to determine the full-capacity difference between each individual cell and the highest-charged individual cell when fully charged, based on the target charging voltage of each individual cell when fully charged, the second mapping relationship between voltage and capacity during the charging process, and the charging capacity difference between the total charging capacity of the battery pack when fully charged and the final total charging capacity during the charging process; wherein, the target charging voltage is obtained by correcting the actual charging voltage of the individual cell when fully charged, and the highest-charged individual cell is the individual cell with the highest actual charging voltage when fully charged; The capacity determination module is configured to determine the total capacity of each individual cell from the vented state to the fully charged state based on the vented capacity difference, the fully charged capacity difference, and the total capacity of the battery pack, and to determine the current total capacity of each individual cell in the fully charged state based on the vented capacity difference and the total capacity of the battery pack. The balancing module is configured to determine the balancing amount of each individual battery based on the total capacity of each individual battery, the current total capacity of each individual battery, and the difference in the fully charged capacity of each individual battery, and to perform charge-discharge balancing on each individual battery based on the balancing amount of each individual battery.
An electronic device includes a memory and a processor, the memory storing a computer program executable by the processor, wherein the processor executes the computer program to implement the steps of the battery equalization processing method according to any one of claims 1-12.
A computer-readable storage medium, wherein a computer program is stored on the computer-readable storage medium, the computer program being executed by a processor to perform the steps of the battery equalization processing method as described in any one of claims 1-12.

Description

Battery equalization processing methods, devices, electronic equipment and storage media Cross-reference of related applications This disclosure claims priority to Chinese Patent Application No. 2024115186308, filed on October 28, 2024, entitled "Battery Equalization Processing Method, Apparatus, Electronic Device and Storage Medium", the entire contents of which are incorporated herein by reference. Technical Field This disclosure relates to the field of battery technology, and more specifically, to a battery equalization processing method, apparatus, electronic device, and storage medium. Background Technology For large-scale energy storage systems, such as electric vehicles and energy storage boxes, multiple battery cells need to be connected in series. Due to differences in manufacturing processes, assembly technologies, and aging paths, the capacity, voltage, and internal resistance of the cells will gradually increase with aging. If not addressed in time, this will lead to a significant reduction in the usable capacity of the battery pack and shorten its lifespan. To fully utilize the charge and discharge performance of the battery pack and slow down its lifespan degradation, it is necessary to dynamically adjust the remaining capacity of each battery cell. In existing technologies, commonly used equalization schemes include capacity equalization and voltage equalization. Capacity equalization mainly identifies the cell with the lowest capacity and calculates the capacity difference between the other cells and the cell with the lowest capacity. Equalization discharge stops when the capacity difference is less than a certain threshold. Voltage equalization mainly identifies the cell with the lowest voltage difference and calculates the voltage difference between the other cells and the cell with the lowest voltage difference. Equalization discharge stops when the voltage difference is less than a certain threshold. Both methods have unreasonable calculations of the equalization amount and unreasonable equalization stopping conditions, resulting in poor battery equalization performance and consequently, short battery life. Summary of the Invention The purpose of this disclosure is to address the shortcomings of the prior art by providing a battery equalization processing method, apparatus, electronic device, and storage medium to improve the accuracy of battery equalization processing. To address the aforementioned technical problems, in a first aspect, this disclosure provides a battery balancing method for performing charge-discharge balancing on individual cells in a battery pack, the method comprising: Based on the target discharge voltage of each individual cell in the venting state, the first mapping relationship between voltage and capacity during the discharge process, and the discharge capacity difference between the total discharge capacity of the battery pack in the venting state and the final total discharge capacity during the discharge process, the discharge capacity difference between each individual cell and the individual cell with the lowest discharge capacity in the venting state is determined; wherein, the target discharge voltage is obtained by correcting the actual discharge voltage of the individual cell in the venting state, and the individual cell with the lowest discharge capacity is the individual cell with the lowest actual discharge voltage in the venting state. Based on the target charging voltage of each individual cell when fully charged, the second mapping relationship between voltage and capacity during the charging process, and the difference in charging capacity between the total charging capacity of the battery pack when fully charged and the final total charging capacity during the charging process, the full-charge capacity difference between each individual cell and the cell with the highest full charge when fully charged is determined; wherein, the target charging voltage is obtained by correcting the actual charging voltage of the individual cell when fully charged, and the cell with the highest full charge is the individual cell with the highest actual charging voltage when fully charged; The total capacity of each individual cell from the vented state to the fully charged state is determined based on the vented capacity difference, the fully charged capacity difference, and the total capacity of the battery pack. Based on the difference in venting capacity of each individual cell and the total capacity of the battery pack, determine the current total capacity of each individual cell when fully charged. Based on the total capacity of each individual battery cell, the current total capacity of each individual battery cell, and the difference in fully charged capacity of each individual battery cell, the equalization amount of each individual battery cell is determined, and the charge and discharge equalization of each individual battery cell is performed based on