CN-116953551-B - Method and device for testing thermal runaway of aged battery pack, electronic equipment and storage medium

CN116953551BCN 116953551 BCN116953551 BCN 116953551BCN-116953551-B

Abstract

The invention provides a thermal runaway testing method, a device, electronic equipment and a storage medium for an aging battery pack, which comprise the steps of obtaining battery pack initial data, thermal runaway reaction data and thermal runaway protection material data of an aging battery pack, establishing an aging battery pack thermal runaway model according to the battery pack initial data and the thermal runaway reaction data, determining the position of the aging battery pack according to the aging battery pack thermal runaway model and the thermal runaway reaction data, determining the arrangement type of a thermal runaway protection material based on the position of the aging battery pack and the thermal runaway protection material data, and determining the arrangement of the aging battery pack according to the position of the aging battery pack, the arrangement type of the thermal runaway protection material and the aging battery pack classification, so as to conduct the thermal runaway test of the aging battery pack according to the arrangement of the aging battery pack to obtain thermal runaway testing parameters.

Inventors

XIE YUNCHENG
DENG KEJUN
TANG YUEHUI
LI CHANG
PENG XINGXING

Assignees

深蓝汽车科技有限公司

Dates

Publication Date: 20260508
Application Date: 20230705

Claims (10)

1. A method for testing thermal runaway of an aged battery pack, the method comprising: Acquiring aging cell classification, battery pack initial data, thermal runaway reaction data and thermal runaway protection material data of a healthy battery pack; establishing an aging battery pack thermal runaway model according to the battery pack initial data and the thermal runaway reaction data, and determining an aging battery cell position according to the aging battery pack thermal runaway model and the thermal runaway reaction data, wherein the aging battery cell position is used for representing battery cell triggering positions of aging types of different target battery cells in the whole pack; determining a thermal runaway protection material placement type based on the aged cell locations and the thermal runaway protection material data; determining an aging battery pack arrangement according to the aging battery cell position, the thermal runaway protection material arrangement type and the aging battery cell classification, so as to perform an aging battery pack thermal runaway test according to the aging battery pack arrangement to obtain thermal runaway test parameters; and establishing an aging battery pack thermal runaway model according to the battery pack initial data and the thermal runaway reaction data, wherein the aging battery pack thermal runaway model comprises the following steps: establishing an initial whole-package thermal runaway model according to the initial data of the battery package; Performing thermal runaway numerical simulation on the initial whole-package thermal runaway model based on a thermal runaway reaction degree function and a battery package heat transfer equation to obtain a middle whole-package thermal runaway model; inputting thermal runaway boundary conditions and thermal runaway physical parameters into the tundish thermal runaway model to obtain an aged battery pack thermal runaway model; Wherein the thermal runaway reaction data comprises the thermal runaway reaction degree function, the battery pack heat transfer equation, the thermal runaway boundary condition, and the thermal runaway physical parameter; wherein determining an aged cell location based on the aged battery pack thermal runaway model and the thermal runaway response data comprises: Performing target cell thermal runaway simulation on the aged battery pack thermal runaway model according to the heating trigger position and the heating trigger range to obtain the temperature rise of the electric shock core; Determining the position of the aged battery cell based on the comparison result of the temperature rise of the electric shock core and the preset temperature rise range; Wherein the thermal runaway reaction data further includes the heating trigger position and the heating trigger range.
2. The aged battery pack thermal runaway test method of claim 1, wherein determining a thermal runaway protection material placement type based on the aged cell location and the thermal runaway protection material data comprises: If the position of the aging battery cell is triggered by the center, determining the arrangement type of the thermal runaway protection material as space-level aerogel; if the aged battery cell position is triggered by the secondary center, determining the arrangement type of the thermal runaway protection material as a thickened mica plate; if the position of the aged battery cell is corner trigger, determining the arrangement type of the thermal runaway protection material as an added heat conduction structural adhesive; The thermal runaway protection material data comprise the aerospace grade aerogel, the thickened mica plate and the added heat conduction structural adhesive.
3. The aged battery pack thermal runaway test method of claim 2, wherein determining an aged battery pack arrangement based on the aged cell location, the thermal runaway protection material arrangement type, and the aged cell classification comprises: determining the arrangement of the whole battery cells according to the positions of the aged battery cells and the aged battery cell classifications; Determining a full pack of protective material arrangement based on the thermal runaway protective material arrangement type and the full pack of cell arrangements; and determining the aged battery pack arrangement according to the whole pack cell arrangement and the whole pack protection material arrangement.
4. The aged battery pack thermal runaway test method according to any one of claims 1-3, wherein prior to obtaining the aged cell classification, the aged battery pack thermal runaway test method further comprises: acquiring temperature and humidity working conditions, charge and discharge working conditions and initial cell capacities of a plurality of healthy cells; Performing accelerated aging attenuation on each healthy battery cell according to the temperature and humidity working conditions and the charge and discharge working conditions to obtain a plurality of aging attenuation battery cells; determining a plurality of capacity attenuation values according to the initial cell capacities and the aged cell capacities of the aged attenuation cells; Classifying each aging attenuation cell according to the comparison result of each capacity attenuation value and the preset capacity attenuation range to obtain an aging cell classification; the temperature and humidity working conditions comprise a high-temperature working condition, a high-humidity working condition and a temperature and humidity superposition working condition.
5. The aged battery pack thermal runaway test method of claim 4, wherein after determining an aged battery pack arrangement based on the aged cell location, the thermal runaway protective material arrangement type, and the aged cell classification, the aged battery pack thermal runaway test method further comprises: According to the arrangement of the aging battery packs, each aging attenuation battery cell and a plurality of thermal runaway protection materials are distributed, so that a test battery pack is obtained; Performing an aging battery pack thermal runaway test on the test battery pack according to a preset heating trigger temperature to obtain thermal runaway test parameters; And evaluating the thermal inhibition protection effect of the thermal runaway protection material arrangement type according to the thermal runaway test parameters.
6. The method of claim 5, wherein after obtaining the aged battery pack thermal runaway model, the aged battery pack thermal runaway test method further comprises: Correcting the thermal runaway model of the aged battery pack according to thermal runaway test data to obtain a corrected battery pack thermal runaway model, wherein the thermal runaway test data are obtained from the thermal runaway reaction data; and taking the corrected battery pack thermal runaway model as the aged battery pack thermal runaway model.
7. An aged battery pack thermal runaway testing device, characterized in that the aged battery pack thermal runaway testing device comprises: the acquisition module is used for acquiring battery pack initial data, thermal runaway reaction data and thermal runaway protection material data of the aged battery cell classification and the healthy battery pack; The aging battery cell position determining module is used for establishing an aging battery pack thermal runaway model according to the battery pack initial data and the thermal runaway reaction data, determining an aging battery cell position according to the aging battery pack thermal runaway model and the thermal runaway reaction data, and concretely comprises the steps of establishing an initial whole pack thermal runaway model according to the battery pack initial data, carrying out thermal runaway numerical simulation on the initial whole pack thermal runaway model based on a thermal runaway reaction degree function and a battery pack heat transfer equation to obtain a middle whole pack thermal runaway model, inputting a thermal runaway boundary condition and a thermal runaway physical parameter into the middle whole pack thermal runaway model to obtain an aging battery pack thermal runaway model, wherein the thermal runaway reaction data comprises the thermal runaway reaction degree function, the battery pack heat transfer equation, the thermal runaway boundary condition and the thermal runaway physical parameter, carrying out target cell thermal runaway simulation on the aging battery pack thermal runaway model according to a heating trigger position and a heating trigger range to obtain a target cell temperature rise, determining an aging battery cell position based on a comparison result of the whole pack thermal runaway model and a preset temperature rise range, wherein the thermal runaway reaction trigger position and the heating trigger position also comprises the heating trigger position and the heating trigger position are used for characterizing the aging battery cell position in the same type; A protective material determination module for determining a thermal runaway protective material placement type based on the aged cell locations and the thermal runaway protective material data; And the battery pack arrangement determining module is used for determining the arrangement of the aged battery packs according to the positions of the aged battery cells, the arrangement type of the thermal runaway protection materials and the classification of the aged battery cells so as to perform the thermal runaway test of the aged battery packs according to the arrangement of the aged battery packs and obtain thermal runaway test parameters.
8. The aged battery pack thermal runaway testing device according to claim 7, further comprising an automatic fire extinguishing and explosion-proof incubator, a test battery pack, a battery pack thermal diffusion tool, an upper computer control module, a power battery performance testing module and an explosion-proof camera monitoring module; the automatic fire-extinguishing explosion-proof incubator is used for extinguishing fire and evacuating smoke for the test battery pack after the thermal runaway test of the aging battery pack is finished; the test battery pack is used for performing an aging battery pack thermal runaway test; The battery pack heat diffusion tool is used for simulating the working condition that the test battery pack is loaded on the whole vehicle to generate gas eruption due to thermal runaway; The upper computer control module is used for monitoring voltage, temperature, current and thermal runaway test images of the aged battery pack thermal runaway test; the power battery performance test module is used for performing charge and discharge or heating triggering on the test battery pack; the anti-explosion camera monitoring module is used for monitoring a thermal runaway test image of the thermal runaway test of the aged battery pack; The test battery pack is connected with the power battery performance test module through a wire harness, the test battery pack is arranged inside the automatic fire-extinguishing explosion-proof incubator, and the battery pack heat diffusion tool is arranged above the test battery pack.
9. An electronic device, the electronic device comprising: One or more processors; Storage means for storing one or more programs that, when executed by the one or more processors, cause the electronic device to implement the aged battery pack thermal runaway test method of any one of claims 1 to 6.
10. A computer-readable storage medium, having stored thereon a computer program which, when executed by a processor of a computer, causes the computer to perform the aged battery pack thermal runaway test method of any one of claims 1 to 6.

Description

Method and device for testing thermal runaway of aged battery pack, electronic equipment and storage medium Technical Field The application relates to the technical field of power batteries, in particular to a thermal runaway testing method and device for an aged battery pack, electronic equipment and a storage medium. Background A lithium ion power battery "thermal runaway" is a phenomenon that a battery is irreversibly failed due to a rapid increase in the temperature of the battery, and is generally failed due to a chain reaction of substances inside the battery caused by extreme conditions, such as mechanical abuse, electrical abuse and thermal abuse. In view of the above problems, the focus of research is mainly on fresh and unattenuated cells, and the triggering effect of aged and attenuated cells on thermal runaway is rarely considered. In addition to the three causes described above, aging decay is also one of the causes of thermal runaway accidents. The battery core can age along with the increase of the use times in the normal cycle charge and discharge process, and the phenomena of metal lithium deposition, electrode structure damage, electrode material phase change, positive and negative electrode active materials, electrolyte decomposition and the like can occur in the battery, so that the capacity attenuation and the internal resistance increase of the battery are further caused, the safety performance of the battery system is reduced, and the thermal runaway is finally triggered. The related art relates to a test of thermal runaway of a battery, and a whole-cladding-level aging attenuation thermal runaway study cannot be performed through aging cell positions and battery pack relations. For example, CN111812529a discloses a method for testing the thermal runaway of aging of a lithium ion battery under a time-varying cycle condition, the aging test of the battery is performed by adopting the time-varying cycle condition to analyze the evolution process of the battery performance, and the thermal runaway test of the battery is performed by extracting test batteries in different aging stages in an adiabatic acceleration calorimeter, so as to obtain the characteristic temperature of the thermal runaway of the battery in different aging stages, and based on the result of the thermal runaway test, the change rule of the thermal runaway characteristic, the coupling relation between the thermal runaway and the aging mechanism, and the influence of different aging conditions on the thermal runaway characteristic of the battery are studied in the whole life cycle. According to the technical scheme, the change rule of thermal runaway characteristics in the whole life cycle of the lithium ion battery is obtained based on ageing lithium ion battery monomer thermal runaway characteristic temperatures with different test temperatures and/or different capacity attenuation ratios, and the adopted time-varying cycle working conditions are converted from new European test cycle (NEDC), global light automobile test cycle (WLTC), chinese automobile running working conditions (CLTC) and the like to form battery equivalent test ageing working conditions. The scheme can not carry out the thermal runaway test of the aged battery pack of the whole pack level through the relation between the aged battery cell position and the battery pack, and the aging attenuation working condition does not comprehensively consider the actual use working condition of a user, so that the test period is long. For another example, CN113848492a discloses a method for testing aging and electric abuse of an unmanned aerial vehicle battery, which belongs to the field of battery safety. The method is mainly characterized in that an unmanned aerial vehicle working condition aging test is conducted on a battery module used by the unmanned aerial vehicle, an electric abuse test is conducted on the battery after aging, and the battery aging condition of the unmanned aerial vehicle after normal working is simulated to search the electric abuse safety performance of the unmanned aerial vehicle after the battery is subjected to working condition aging. According to the working conditions of the unmanned aerial vehicle, including hovering and high-power taking-off and landing working conditions, the aging test working conditions are used for simulating the working conditions of the unmanned aerial vehicle, and the electric abuse test working conditions recommend to select overcharge, so that the safety performance of the unmanned aerial vehicle after aging can be well evaluated, and serious safety problems caused by battery use are avoided. According to the scheme, the battery module used by the unmanned aerial vehicle is subjected to an aging test under the typical working condition of the unmanned aerial vehicle, and after aging, the battery is subjected to an electric abuse test, so that the electric abuse performance of the battery of the unmanne