电化学（中英文）2024，Vol.30Issue(9)：10-24,15.DOI:10.61558/2993-074X.3468
基于电化学-热-力耦合模型的快速充电下锂离子电池的老化特性分析
Aging Characteristics of Lithium-Ion Battery Under Fast Charging Based on Electrochemical-thermal-mechanical Coupling Model
摘要
Abstract
The aging characteristics of lithium-ion battery(LIB)under fast charging is investigated based on an electro-chemical-thermal-mechanical(ETM)coupling model.Firstly,the ETM coupling model is established by COMSOL Multiphysics.Subsequently,a long cycle test was conducted to explore the aging characteristics of LIB.Specifically,the effects of charging(C)rate and cycle number on battery aging are analyzed in terms of nonuniform distribution of solid electrolyte interface(SEI),SEI formation,thermal stability and stress characteristics.The results indicate that the increases in C rate and cycling led to an increase in the degree of nonuniform distribution of SEI,and thus a consequent increase in the capacity loss due to the SEI formation.Meanwhile,the increases in C rate and cycle number also led to an increase in the heat generation and a decrease in the heat dissipation rate of the battery,respectively,which result in a decrease in the thermal stability of the electrode materials.In addition,the von Mises stress of the positive electrode material is higher than that of the negative electrode material as the cycling proceeds,with the positive electrode material exhibiting tensile deformation and the negative electrode material exhibiting compressive deformation.The available lithium ion concentration of the positive electrode is lower than that of the negative electrode,proving that the tensile-type fracture occurring in the positive material under long cycling dominated the capacity loss process.The aforementioned studies are helpful for researchers to further explore the aging behavior of LIB under fast charging and take corresponding preventive measures.关键词
锂离子电池/老化特性/快充/电化学-热-力耦合模型Key words
Lithium-ion battery/Aging characteristics/Fast charging/Electrochemical-thermal-mechanical coupling model引用本文复制引用
左东旭,李培超..基于电化学-热-力耦合模型的快速充电下锂离子电池的老化特性分析[J].电化学（中英文）,2024,30(9):10-24,15.基金项目
This work was funded by the National Natural Science Foundation of China(Grant No.12272217). （Grant No.12272217）
