锂离子电池等效刚度的动态测量方法  

Dynamic measurement of lithium-ion battery equivalent stiffness

作　　者：李金翰 刘帅邦 王文伟 杨晓光[1,2] LI Jinhan;LIU Shuaibang;WANG Wenwei;YANG Xiaoguang(Shenzhen Automotive Research Institute,Beijing Institute of Technology,Shenzhen Guangdong 518118,China;Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学深圳汽车研究院,广东深圳518118 [2]北京理工大学,北京100081

出　　处：《电源技术》2025年第4期750-754,共5页Chinese Journal of Power Sources

基　　金：国家重点研发计划(2022YFB2404300);国家自然科学基金面上项目(52072039);深圳市科技计划资助(JCYJ20220530172601003)。

摘　　要：电池内部含有电化学储能材料,其机械特征例如厚度、刚度等会随着电池的充放电发生显著变化。零部件刚度影响整车的机械特性、寿命和安全性,因此研究锂离子电池在充放电过程中的等效刚度变化非常重要。提出了一种锂离子电池等效刚度的动态测量方法,通过测量电池的自由膨胀厚度和在给定约束条件下的压力,获取了锂离子电池在充放电过程中的等效刚度。实验结果表明,在预紧力介于800~1800 N之间时,实验电池的等效刚度介于13550~27550 N/mm之间,且电池在较大压力和较低SOC情况下的等效刚度较大。提出的方法可进一步推广,用于获取电池全生命周期的刚度,指导锂离子电池安全设计。The electrochemical energy storage materials inside a battery exhibit significant changes in their mechanical properties,such as thickness and stiffness,during the charge and discharge processes.The stiffness of components affects the mechanical characteristics,lifespan,and safety of the entire vehicle,making it crucial to study the equivalent stiffness variation of lithium-ion batteries during charging and discharging.This paper proposed a dynamic measurement method for the equivalent stiffness of lithium-ion batteries.By measuring the free expansion thickness of the battery and the pressure under given constraint conditions,the equivalent stiffness of the lithium-ion battery during the charging and discharging process was obtained.The experimental results show that when the preload force is between 800 and 1800 N,the equivalent stiffness of the experimental battery ranges from 13550 to 27550 N/mm.Furthermore,the equivalent stiffness of the battery is larger under higher pressure and lower states of charge(SOC).The method proposed in this paper can be further extended to obtain the stiffness throughout the entire lifecycle of the battery,providing guidance for the safe design of lithium-ion batteries.

关 键 词：锂离子电池 电池膨胀力 电池刚度 电池安全 

分 类 号：TM912.9[电气工程—电力电子与电力传动]