基于特征阻抗及滑动t方法的变电流快充析锂检测方法  

Lithium plating detection based on characteristic impedance and sliding t-test with multi-stage current fast charging

作　　者：郝祯淇 王学远[1,2] 李嘉伟 戴海峰[1,2] 魏学哲[1,2] HAO Zhenqi;WANG Xueyuan;LI Jiawei;DAI Haifeng;WEI Xuezhe(School of Automotive Studies,Tongji University,Shanghai 201804,China;Clean Energy Automotive Engineering Center,Tongji University,Shanghai 201804,China)

机构地区：[1]同济大学汽车学院,201804 [2]同济大学新能源汽车工程中心,201804

出　　处：《汽车安全与节能学报》2024年第3期344-350,共7页Journal of Automotive Safety and Energy

基　　金：国家自然科学基金项目(52207242);汽车安全与节能国家重点实验室开放基金课题(KFY2226)。

摘　　要：在低温、高倍率等充电情况下,锂离子电池的石墨负极会发生析锂现象,对电池的寿命和安全性造成严重影响。为了解决锂离子电池在变电流快充工况下析锂的在线检测问题,该文提出了一种基于特征阻抗与滑动t检验的在线析锂检测方法。采用在直流充电电流的基础上叠加1 Hz正弦交流激励电流来实时测量特征频率阻抗,探究变电流充电时阻抗随电池析锂的变化规律;继而利用特征阻抗实部的变化与电池负极析锂的相关性,针对变电流快充工况,提出了基于滑动t方法的在线检测析锂起始点的检测方法。结果表明:该方法可以实现充电过程中5%SOC的延迟内识别析锂起始点,有利于形成闭环充电策略,最大限度地减少析锂危害。Under low temperature and high-rate charging,the graphite anode of lithium-ion battery will have a lithium plating phenomenon,which has a serious impact on the life and safety of the battery.An on-line detection method based on characteristic impedance and sliding t-test was proposed to realize the on-line detection of lithium plating of lithium-ion battery under variable current fast charge condition.The characteristic frequency impedance was measured in real time by superimposing 1 Hz sinusoidal excitation alternating current on the direct current charging.Based on the correlation between the change of the real part of characteristic impedance and the lithium plating of the negative electrode of the battery,an on-line detection method of lithium plating starting point based on sliding t-method was proposed for the fast-charging condition of variable current.The results show that this method can realize the delayed identification of the initial point of lithium plating within 5%SOC during the charging process,which is conducive to forming a closed-loop charging strategy and minimizing the harm of lithium plating.

关 键 词：锂离子电池 析锂 阻抗 快速充电 滑动t检验 

分 类 号：TM911.3[电气工程—电力电子与电力传动]