CN-122017595-A - Modeling method and device for battery pack, electronic equipment and storage medium

CN122017595ACN 122017595 ACN122017595 ACN 122017595ACN-122017595-A

Abstract

The invention provides a modeling method, a device, electronic equipment and a storage medium of a battery pack, which relate to the technical field of vehicles and are used for modeling the battery pack, and the method comprises the steps of utilizing a battery pack test device to perform charge and discharge tests based on different working condition parameters to obtain actual energy data, an actual SOC variation range, actual capacity data and a first association relation of the battery pack under a plurality of working conditions; the method comprises the steps of determining charge-discharge efficiency-temperature data of a battery pack based on actual energy data under a plurality of working conditions and inclusion temperature of the battery pack under the plurality of working conditions, determining heating value-temperature data of the battery pack based on the charge-discharge efficiency-temperature data of the battery pack, determining capacity-temperature data of the battery pack based on actual capacity data under the plurality of working conditions and inclusion temperature under the plurality of working conditions, determining a second association relationship based on a first association relationship under the plurality of working conditions, and constructing a battery pack model based on the capacity-temperature data, the second association relationship and the heating value-temperature data.

Inventors

ZHOU SHUAI
YAN XU
YAN JUNJIE
ZHANG JIE

Assignees

重庆长安汽车股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260227

Claims (12)

1.A method of modeling a battery pack, comprising: The method comprises the steps of carrying out charge and discharge tests by using a battery pack test device based on different working condition parameters to obtain actual energy data, an actual SOC variation range, actual capacity data and a first association relation of a battery pack under a plurality of working conditions, wherein the first association relation is used for indicating the rule that the voltage of the battery pack varies along with the SOC of the battery pack; Determining charge-discharge efficiency-temperature data of the battery pack based on the actual energy data under the plurality of working conditions and the pack body temperature of the battery pack under the plurality of working conditions; Determining heating value-temperature data of the battery pack based on charge-discharge efficiency-temperature data of the battery pack; Determining capacity-temperature data of the battery pack based on the actual capacity data under the plurality of working conditions and the pack body temperature of the battery pack under the plurality of working conditions; Determining a second association relationship based on the first association relationship under the working conditions, wherein the second association relationship represents the comprehensive rule of the voltage variation along with the SOC of the battery pack under different temperature conditions; And constructing a battery pack model based on the capacity-temperature data, the second association relationship and the heating value-temperature data.
2. The method of claim 1, wherein the actual energy data comprises discharge energy data for which the operating state of the battery pack is discharge and charge energy data for which the operating state of the battery pack is charge; the determining charge-discharge efficiency-temperature data of the battery pack based on the actual energy data under the plurality of working conditions and the pack body temperature of the battery pack under the plurality of working conditions includes: Determining discharge energy data and charging energy data for each working condition of the battery pack, wherein the discharge energy data comprises first discharge energy, first charging energy and first net discharge energy, and the charging energy data comprises second discharge energy and second charging energy; Determining charge-discharge efficiency of the battery pack under each working condition based on an energy balance equation between the second charge energy, the second discharge energy, the first charge energy and the first net discharge energy; And determining charge-discharge efficiency-temperature data of the battery pack based on charge-discharge efficiency corresponding to the pack body temperature of the battery pack under the working conditions.
3. The method of claim 1, wherein the charge-discharge efficiency of the battery pack is determined by: Correcting the actual energy data under the working conditions based on the ratio of the reference SOC variation range to the actual SOC variation range to obtain corrected actual energy data under the working conditions; And determining the charge and discharge efficiency of the battery pack based on the corrected actual energy data under the working conditions.
4. The method of claim 3, wherein the charge-discharge efficiency of the battery pack satisfies the following relationship: Wherein Eff represents the charge-discharge efficiency of the battery pack, Indicating the corrected second charging energy, Representing the corrected second discharge energy, Indicating the corrected first charging energy, Indicating the corrected first discharge energy, Representing the corrected first net discharge energy.
5. The method of claim 1, wherein the determining the capacity-temperature data of the battery pack based on the actual capacity data for the plurality of conditions and the pack body temperature of the battery pack for the plurality of conditions comprises: Correcting the actual capacity data under the working conditions based on the ratio of the reference SOC variation range to the actual SOC variation range to obtain corrected actual capacity data under the working conditions; And obtaining capacity-temperature data of the battery pack based on the corrected actual capacity data corresponding to the pack body temperature of the battery pack under the working conditions.
6. The method of claim 1, wherein the first association is determined by: determining an initial association relation based on voltages corresponding to different SOC values of the battery pack, wherein the initial association relation represents a preliminary rule of the voltage of the battery pack along with the change of the SOC; And correcting the initial association relation based on a correction coefficient to obtain the first association relation, wherein the correction coefficient is used for representing the deviation degree of the predicted net discharge amount and the actual net discharge amount of the battery pack.
7. The method of claim 1, wherein the constructing the battery pack model based on the capacity-temperature data, the second association relationship, and the heat generation amount-temperature data comprises: based on the capacity-temperature data and the second association relation, constructing an electrical module of the battery pack model, wherein the electrical module is used for representing voltage output characteristics and capacity change rules of the battery pack under different temperature and SOC conditions; And constructing a heating value module of the battery pack model based on the heating value-temperature data, wherein the heating value module is used for representing the corresponding relation between the heating value of the battery pack and the temperature change.
8. The method according to claim 1, wherein the method further comprises: Obtaining correction coefficient-temperature data based on correction coefficients corresponding to the inclusion temperatures of the battery packs under the working conditions; The constructing the battery pack model based on the capacity-temperature data, the second association relationship, and the heat generation amount-temperature data includes: and constructing the battery pack model based on the correction coefficient-temperature data, the capacity-temperature data, the second association relationship, and the heat generation amount-temperature data.
9. A modeling apparatus for a battery pack, the apparatus comprising: The testing unit is used for carrying out charge and discharge tests based on different working condition parameters by utilizing a battery pack testing device to obtain actual energy data, an actual SOC variation range, actual capacity data and a first association relation of the battery pack under the working conditions, wherein the first association relation is used for indicating the rule that the voltage of the battery pack changes along with the SOC of the battery pack; The first determining unit is used for determining charge-discharge efficiency-temperature data of the battery pack based on the actual energy data under the working conditions and the pack body temperature of the battery pack under the working conditions; a second determination unit configured to determine heating value-temperature data of the battery pack based on charge-discharge efficiency-temperature data of the battery pack; a third determining unit configured to determine capacity-temperature data of the battery pack based on actual capacity data under the plurality of working conditions and a pack body temperature of the battery pack under the plurality of working conditions; the fourth determining unit is used for determining a second association relation based on the first association relation under the working conditions, wherein the second association relation represents the comprehensive rule of the voltage along with the change of the SOC under different temperature conditions of the battery pack; and a fifth determining unit configured to construct the battery pack model based on the capacity-temperature data, the second association relationship, and the heat generation amount-temperature data.
10. An electronic device is characterized by comprising a processor; a memory for storing the processor-executable instructions; Wherein the processor is configured to execute the instructions to implement the method of any one of claims 1 to 8.
11. A computer readable storage medium, characterized in that, when computer-executable instructions stored in the computer readable storage medium are executed by a processor of an electronic device, the electronic device is capable of performing the method of any one of claims 1 to 8.
12. A computer program product, characterized in that the computer program product, when run in an electronic device, causes the electronic device to implement the method of any one of claims 1 to 8.

Description

Modeling method and device for battery pack, electronic equipment and storage medium Technical Field The invention relates to the technical field of vehicles, in particular to a modeling method and device for a battery pack, electronic equipment and a storage medium. Background Among the numerous subsystems of a vehicle, a power battery pack is one of the most critical subsystems of an electric vehicle. Generally, the capacity of the power battery pack basically determines the energy consumption level and the driving range of the vehicle, and the charge and discharge capacity of the battery determines the fast charge efficiency, the power response speed and the continuous output capacity under the limit working condition of the vehicle. Therefore, the development of the power battery pack becomes an important ring in the development of the whole vehicle product. In the development process of the power battery pack, the development cost and period are often reduced by establishing a model of the battery pack to replace a part of real vehicle tests. Therefore, how to model the battery pack is a problem to be solved at present. Disclosure of Invention One of the purposes of the invention is to provide a modeling method, a device, an electronic device and a storage medium for a battery pack, so as to realize the modeling of the battery pack. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The first aspect provides a modeling method of a battery pack, which comprises the steps of conducting charge and discharge tests by using a battery pack test device based on different working condition parameters to obtain actual energy data, an actual SOC variation range, actual capacity data and a first association relation of the battery pack under a plurality of working conditions, wherein the first association relation is used for indicating the rule that the voltage of the battery pack changes along with the SOC of the battery pack, the working condition parameters are used for simulating working conditions of the battery pack under different environment temperatures, based on the actual energy data under the plurality of working conditions and the pack body temperature of the battery pack under the plurality of working conditions, determining charge and discharge efficiency-temperature data of the battery pack, based on the charge and discharge efficiency-temperature data of the battery pack, determining heating value-temperature data of the battery pack, based on the actual capacity data under the plurality of working conditions and the pack body temperature of the battery pack under the plurality of working conditions, determining a second association relation, wherein the second association relation is used for indicating the comprehensive rule that the voltage changes along with the SOC of the battery pack under the different temperature conditions, and building a battery pack model based on the capacity-temperature data, the second association relation and the heating value-temperature data. The method has the beneficial effects that the battery pack model is constructed by acquiring the actual energy data, the actual SOC variation range, the actual capacity data and the first association relation of the battery pack under each working condition, then acquiring the charge-discharge efficiency-temperature data, the heating value-temperature data, the capacity-temperature data and the second association relation according to the data, and finally constructing the battery pack model based on the capacity-temperature data, the second association relation and the heating value-temperature data. When the battery pack is modeled, the electrical characteristics and the thermal characteristics of the battery pack are generally considered, wherein the electrical characteristics can reflect the voltage output, capacity change and energy conversion rules of the battery pack under different working conditions, and the thermal characteristics can reflect the heat generation, emission and temperature change rules of the battery pack in the energy conversion process. The heat productivity-temperature data can reflect the change rule of converting energy loss into heat under different temperature conditions of the battery pack, the capacity-temperature data can reflect the influence of temperature on the capacity of the battery pack, the second association relationship can reflect the rule of voltage change along with the SOC under different temperatures, and the three can jointly reflect the electric characteristic and the thermal characteristic of the battery pack under different temperature and SOC coupling working conditions, so that the modeling of the battery pack can be completed. Further, the actual energy data comprises discharge energy data of which the working state of the battery pack is discharge and charge energy data of which the working state of the battery pack i