CN-122017619-A - Three-element lithium battery stability analysis method apparatus, device, medium, and product

CN122017619ACN 122017619 ACN122017619 ACN 122017619ACN-122017619-A

Abstract

The application discloses a method, a device, equipment, a medium and a product for analyzing the stability of a ternary lithium battery, and relates to the field of stability analysis of lithium batteries; in the storage process, circuit parameters and the concentration of each gas are obtained in real time, the interface resistance value is obtained at intervals of preset sampling frequency, the content of each component in the positive pole piece and the negative pole piece after the storage is finished is obtained, the obtained circuit parameters, the concentration of each gas, the interface resistance value and the content of each component in the pole piece are subjected to principal component analysis to obtain parameters obviously related to the stability degradation of the ternary lithium battery, and the time period of the stability degradation is determined according to the obtained values of the parameters obviously related to the stability degradation of the ternary lithium battery.

Inventors

CHEN XIAODONG
JIAO SHUQIANG
SONG WEILI
CHEN HAOSEN
LI NA
LV SIQI
SHI BOWEN
LIANG ZHEN

Assignees

兰州理工大学

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. The method for analyzing the stability of the ternary lithium battery is characterized by comprising the following steps of: storing the ternary lithium battery in-situ electrochemical cell within a preset time period and at a preset temperature; in the storage process, circuit parameters of the ternary lithium battery in-situ electrochemical cell and the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell are obtained in real time, and interface resistance values of the ternary lithium battery in-situ electrochemical cell are obtained at intervals of preset sampling frequency; Acquiring the content of each component in a positive electrode plate and a negative electrode plate in an in-situ electrochemical cell of the ternary lithium battery after storage; Carrying out principal component analysis on the obtained circuit parameters of the ternary lithium battery in-situ electrochemical cell, the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell, the interface resistance value of the ternary lithium battery in-situ electrochemical cell and the content of each component in the positive electrode plate and the negative electrode plate in the ternary lithium battery in-situ electrochemical cell to obtain parameters obviously related to the stability degradation of the ternary lithium battery; And determining the time period of the stability degradation of the in-situ electrochemical cell of the ternary lithium battery according to the obtained value of the parameter obviously related to the stability degradation of the ternary lithium battery.
2. The method for analyzing stability of a ternary lithium battery according to claim 1, wherein the in-situ electrochemical cell of the ternary lithium battery is stored within a preset time period and at a preset temperature, and specifically comprises: And storing the ternary lithium battery in-situ electrochemical cell by adopting temperature control equipment within a preset time period and at a preset temperature.
3. The method for analyzing the stability of the ternary lithium battery according to claim 1, wherein the method for acquiring the circuit parameters of the ternary lithium battery in-situ electrochemical cell and the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell in real time specifically comprises the following steps: acquiring circuit parameters of an in-situ electrochemical cell of the ternary lithium battery in real time by adopting an electrochemical workstation; Acquiring partial pressure of each gas generated by an in-situ electrochemical cell of the ternary lithium battery in real time by adopting a differential electrochemical mass spectrometer; The concentration of each gas is determined based on the partial pressure of each gas.
4. The method for analyzing the stability of the ternary lithium battery according to claim 1, wherein the interface resistance value of the ternary lithium battery in-situ electrochemical cell is obtained at intervals of a preset sampling frequency, and the method specifically comprises the following steps: Presetting sampling frequency at each interval, and carrying out primary electrochemical impedance spectrum test on the ternary lithium battery in-situ electrochemical cell by adopting an electrochemical workstation; constructing an equivalent circuit model corresponding to each electrochemical impedance spectrum test according to the data obtained by the electrochemical impedance spectrum test; And determining the interface resistance value of the ternary lithium battery in-situ electrochemical cell corresponding to each electrochemical impedance spectrum test according to the equivalent circuit model corresponding to each electrochemical impedance spectrum test.
5. The method for analyzing the stability of the ternary lithium battery according to claim 1, wherein the method for acquiring the content of each component in the positive electrode plate and the negative electrode plate in the in-situ electrochemical cell of the ternary lithium battery after the storage is finished comprises the following steps: transferring the in-situ electrochemical cell of the ternary lithium battery after storage to a glove box filled with inert gas for disassembly to obtain a positive pole piece and a negative pole piece; adopting dimethyl carbonate to clean electrolyte on the surfaces of the positive electrode plate and the negative electrode plate; transferring the cleaned positive pole piece and the cleaned negative pole piece into a drying oven in a sealing way through a centrifuge tube for drying; And (3) hermetically transferring the dried positive electrode plate and the dried negative electrode plate into a flight time secondary ion mass spectrometry device through a vacuum transfer bin, and carrying out component analysis on the dried positive electrode plate and the dried negative electrode plate in the flight time secondary ion mass spectrometry device to obtain the contents of all components in the dried positive electrode plate and the dried negative electrode plate.
6. The method for analyzing the stability of the ternary lithium battery according to claim 1, wherein the determining the period of time for the stability degradation of the in-situ electrochemical cell of the ternary lithium battery according to the obtained value of the parameter significantly related to the stability degradation of the ternary lithium battery specifically comprises: drawing curves corresponding to the parameters obviously related to the stability degradation of the ternary lithium battery by taking the time as an abscissa and taking the value of the acquired parameters obviously related to the stability degradation of the ternary lithium battery at each time as an ordinate; And determining the time period of the stability degradation of the in-situ electrochemical cell of the ternary lithium battery according to the curves corresponding to the parameters obviously related to the stability degradation of the ternary lithium battery.
7. The utility model provides a ternary lithium battery stability analytical equipment which characterized in that, ternary lithium battery stability analytical equipment includes: the storage module is used for storing the ternary lithium battery in-situ electrochemical cell in a preset time period and at a preset temperature; The device comprises a first acquisition module, a second acquisition module and a third acquisition module, wherein the first acquisition module is used for acquiring circuit parameters of the ternary lithium battery in-situ electrochemical cell and the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell in real time in the storage process, and acquiring interface resistance values of the ternary lithium battery in-situ electrochemical cell at intervals of preset sampling frequency; the second acquisition module is used for acquiring the content of each component in the positive electrode plate and the negative electrode plate in the in-situ electrochemical cell of the ternary lithium battery after the storage is finished; The main component analysis module is used for carrying out main component analysis on the obtained circuit parameters of the ternary lithium battery in-situ electrochemical cell, the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell, the interface resistance value of the ternary lithium battery in-situ electrochemical cell and the content of each component in the positive electrode plate and the negative electrode plate in the ternary lithium battery in-situ electrochemical cell to obtain parameters obviously related to the stability degradation of the ternary lithium battery; And the stability analysis module is used for determining the time period of the stability degradation of the in-situ electrochemical cell of the ternary lithium battery according to the acquired value of the parameter obviously related to the stability degradation of the ternary lithium battery.
8. A computer device comprising a memory, a processor and a computer program stored on the memory and executable on the processor, wherein the processor executes the computer program to implement the ternary lithium battery stability analysis method of any of claims 1-6.
9. A computer readable storage medium having stored thereon a computer program, characterized in that the computer program, when executed by a processor, implements the ternary lithium battery stability analysis method of any of claims 1-6.
10. A computer program product comprising a computer program, characterized in that the computer program, when executed by a processor, implements the ternary lithium battery stability analysis method of any one of claims 1-6.

Description

Three-element lithium battery stability analysis method apparatus, device, medium, and product Technical Field The application relates to the field of stability analysis of lithium batteries, in particular to a method, a device, equipment, a medium and a product for stability analysis of a ternary lithium battery. Background The ternary lithium battery is widely applied to the fields of new energy automobiles, low-altitude aircrafts and the like due to the advantages of high energy density, high power density and the like. However, when the ternary lithium battery is in service or stored in a high-temperature environment, the problems of interface degradation, electrolyte decomposition gas production, electrode component loss and the like are very easy to occur, and the storage life and the use safety of the battery are seriously affected. Therefore, the method accurately captures the interface dynamics (interface resistance value) change, the gas evolution law and the electrode component degradation characteristics of the ternary lithium battery in the high-temperature service and storage process, and has important significance for optimizing a battery material system, improving the battery structural design and improving the high-temperature storage performance of the battery. In the related art, a single test means is mostly adopted for stability analysis in the high-temperature storage process of the ternary lithium battery, for example, interface resistance change is researched only through electrochemical impedance spectroscopy (Electrochemical Impedance Spectroscopy, EIS), or gas production behaviors are researched only through differential electrochemical mass spectrometry (DIFFERENTIAL ELECTROCHEMICAL MASS SPECTROMETRY, DEMS), so that stability analysis efficiency is low. Disclosure of Invention The application aims to provide a stability analysis method, device, equipment, medium and product of a ternary lithium battery, which can improve the efficiency of stability analysis. In order to achieve the purpose, the application provides a scheme that in the first aspect, the application provides a method for analyzing the stability of a ternary lithium battery, which comprises the steps of storing an in-situ electrochemical cell of the ternary lithium battery in a preset time period and at a preset temperature. In the storage process, circuit parameters of the ternary lithium battery in-situ electrochemical cell and the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell are obtained in real time, and interface resistance values of the ternary lithium battery in-situ electrochemical cell are obtained at intervals of preset sampling frequency. The circuit parameter is open circuit voltage or discharge capacity. And obtaining the content of each component in the positive electrode plate and the negative electrode plate in the ternary lithium battery in-situ electrochemical cell after the storage is finished. And carrying out principal component analysis on the obtained circuit parameters of the ternary lithium battery in-situ electrochemical cell, the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell, the interface resistance value of the ternary lithium battery in-situ electrochemical cell and the content of each component in the positive electrode plate and the negative electrode plate in the ternary lithium battery in-situ electrochemical cell to obtain the parameters obviously related to the stability degradation of the ternary lithium battery. And determining the time period of the stability degradation of the in-situ electrochemical cell of the ternary lithium battery according to the obtained value of the parameter obviously related to the stability degradation of the ternary lithium battery. In a second aspect, the application provides a stability analysis device for a ternary lithium battery, which comprises a storage module, a storage module and a storage module, wherein the storage module is used for storing an in-situ electrochemical cell of the ternary lithium battery in a preset time period and at a preset temperature. The first acquisition module is used for acquiring circuit parameters of the ternary lithium battery in-situ electrochemical cell and the concentration of each gas generated by the ternary lithium battery in-situ electrochemical cell in real time in the storage process, and acquiring interface resistance of the ternary lithium battery in-situ electrochemical cell at intervals of preset sampling frequency. The circuit parameter is open circuit voltage or discharge capacity. The second acquisition module is used for acquiring the content of each component in the positive electrode plate and the negative electrode plate in the in-situ electrochemical cell of the ternary lithium battery after storage. The main component analysis module is used for carrying out main component analysis on the