锂离子动力电池外部短路测试平台开发与试验分析

Experimental Platform Development and Characteristics Analysis of External Short Circuit in Lithium-ion Batteries

动力电池安全性是制约电动汽车发展的关键因素,近年来由动力电池引发的安全事故引起了极高的公众关注度。动力电池外部短路是电动汽车安全事故主因之一,也是触发电池热失控的重要诱因之一。针对某商用锂离子动力电池,开发了动力电池外部短路测试平台,系统性地开展了不同初始荷电状态(State of charge,SOC)、环境温度、短路电阻值、短路时间和老化状态条件下动力电池单体和系统的外部短路试验,数据分析揭示了外部短路下动力电池的电-热特性及其失效行为的演变规律。研究将为动力电池外部短路故障数据库的建立、建模、故障诊断及温升预测的研究提供数据支撑,为动力电池安全管理提供指导。

Battery safety, as a key factor, restricts the development of electric vehicles(EVs). Safety incidents caused by batteries have attracted much public attention in recent years. External short circuit(ESC) is one of the reasons of safety incidents in EVs, and it is also one of the reasons that trigger the thermal runaway of batteries. ESC test platforms for commercialized lithium-ion battery cells and packs are developed. Under different initial state of charge, ambient temperature, short-circuit resistance values, short-circuit durations, and aging conditions, systematic ESC experiments on battery cells and packs are conducted. The influence of initial conditions on battery electro-thermal characteristics is studied and the failure principle of ESC batteries is revealed. The research in this paper will provide data support for the establishment of the ESC fault database, and study of modeling, fault diagnosis and temperature prediction of ESC, which will further lay the foundation for the safety management of lithium-ion batteries for EVs.