锂离子电池外部短路热失控失效特征及机理  

Failure Characteristics and Mechanism of External Short-circuit Thermal Runaway of Lithium-ion Battery

作　　者：安周建 安娴 杜小泽 赵亚兵 时天禄 张东[1,2] AN Zhoujian;AN Xian;DU Xiaoze;ZHAO Yabing;SHI Tianlu;ZHANG Dong(School of Energy and Power Engineering,Lanzhou University of Technology,Lanzhou 730050,China;Gansu Key Laboratory of Biomass and Solar Complementary Energy Supply System,Lanzhou 730050,China)

机构地区：[1]兰州理工大学能源与动力工程学院,兰州730050 [2]甘肃省生物质能与太阳能互补供能系统重点实验室,兰州730050

出　　处：《工程热物理学报》2024年第9期2742-2749,共8页Journal of Engineering Thermophysics

基　　金：国家自然科学基金项目(No.52206087,No.52130607);甘肃省重点研发计划项目(No.22YF7GA163);甘肃省教育厅产业支撑计划项目(No.2022CYZC-21,No.2021CYZC-27);甘肃省教育厅“双一流”科研重点项目(No.GCJ2022-38);兰州理工大学博士科研启动经费项目(No.061907);兰州理工大学红柳优秀青年项目。

摘　　要：本文对锂离子电池外部短路时的电热特性及其失效机理进行了分析,并针对未发生热失控的电池在后续使用中的性能表现以及其内部潜在的热失控风险进行了探究。结果表明,外部短路时电池的温度和电压变化与内阻有关,且内阻随着SOC和短路电流而变化。进一步外部短路电池伴随着电解液蒸发、锂金属沉积、电极颗粒破裂、隔膜闭孔等现象,影响着内部Li^(+)传输过程。对未发生热失控的电池进行了循环测试,电池容量在循环中得到恢复,极化内阻降低至初始水平,但欧姆内阻高于初始值。并且通过二次短路分析了此类电池内部潜在的热失控风险。In this paper,the electrothermal characteristics and failure mechanism of lithium-ion batteries during external short circuit were analyzed,and the performance of batteries without thermal runaway in subsequent use and the potential thermal runaway risk were explored.The results indicated that the temperature and voltage changes of the battery during external short circuits were related to the internal resistance which changes with SOC and short-circuit current.Further external short-circuit batteries were accompanied by phenomena such as electrolyte evaporation,lithium metal deposition,electrode particle rupture,and membrane closure,which affect the internal Li^(+)transport process.The battery without Thermal runaway was tested in the cycle.The battery capacity was recovered in the cycle,and the polarization internal resistance was reduced to the initial level,but the ohmic internal resistance was higher than the initial value.The potential risk of Thermal runaway inside such batteries was analyzed through the secondary short circuit.

关 键 词：锂离子电池 外部短路 内阻 电–热特性 

分 类 号：TM911[电气工程—电力电子与电力传动]