不同荷电状态下动力锂离子电池的热失控  

Thermal runaway of power Li-ion battery under different state of charge

作　　者：张凯博 贾凯丽 徐晓明[1] 曾涛[1] ZHANG Kai-bo;JIA Kai-li;XU Xiao-ming;ZENG Tao(Tianjin Lishen Battery Joint-Stock Co.,Ltd.,Tianjin 300384,China)

机构地区：[1]天津力神电池股份有限公司,天津300384

出　　处：《电池》2022年第6期642-645,共4页Battery Bimonthly

摘　　要：锂离子电池的热失控研究具有重要的意义。采用1000 W外部热源,在不同荷电状态(SOC)下进行三元正极材料动力锂离子电池的热失控实验,探究三元正极材料电池引发的热安全问题。通过40%、60%和70%SOC时的热失控现象,分析温度和时间的关系,研究质量和电压的变化。70%SOC热失控时,出现3 s以上的起火现象。随着SOC的增加,不同SOC与热失控发生时间呈反比,热失控峰值温度逐渐升高。SOC越高,正负极材料的反应活性提升,发生初始副反应的时间越早,热失控危险性越高,放热反应越剧烈;此外,质量损失率也越大,厚度膨胀率增加,开路电压骤降加快。Research on thermal runaway of Li-ion battery was of great significance.Thermal runaway experiment of ternary cathode material power Li-ion battery under different state of charge(SOC)with 1000 W external heat source was carried out to explore the thermal safety problems caused by ternary cathode material battery.Through the thermal runaway phenomenon at 40%,60%and 70%SOC,the relation between temperature and time was analyzed,the changes of mass and voltage were studied.The 70%SOC thermal runaway pheno-menon occurred more than 3 s fire phenomenon.With the increase of SOC,different SOC was inversely proportional to the time point of thermal runaway,the peak temperature of thermal runaway gradually increased.The higher the SOC,the higher the reactivity of the cathode and anode materials,the earlier the initial side reaction occured,the higher the risk of thermal runaway and the more intense the exothermic reaction.In addition,the mass loss rate was also increased,the thickness expansion rate was increased and the open circuit voltage drop was accelerated.

关 键 词：锂离子电池 动力电池 三元正极材料 荷电状态(SOC) 热失控 热稳定性 

分 类 号：TM912.9[电气工程—电力电子与电力传动]