本安设备用锂电池失效模式及典型试验分析

Failure Modes and Typical Test Analysis of Lithium Battery Used in Intrinsic Safety Apparatus

锂电池是本质安全型设备中与本质安全性能有关的重要元件。介绍了锂电池的分类及各自优缺点。圆柱形锂电池可大电流放电、输出稳定;软包锂电池内阻小、设计灵活。分析研究了锂电池的故障模式机理与影响。锂电池故障主要出现在正极、负极、隔膜、有机溶剂、焊接端、壳体。分析了各个部分的失效模式、失效机理及其现象。锂电池在测试过程中,充放电需按照相应规格书参数要求进行。在进行泄漏试验时,必须分别对带有正温度系数(PTC)热敏电阻保护及不带PTC热敏电阻保护的锂电池进行试验。最后,对LG18650锂电池进行试验,并验证了上述分析的正确性。

Lithium battery is an important element related to intrinsic safety performance in intrinsically safe devices. The classification of lithium batteries and their advantages and disadvantages are introduced. Cylindrical lithium battery can be discharged with large current,and with good output stability; soft packaging lithium battery features low internal resistance and flexible design. The failure mode mechanisms of lithium battery and their influence are analyzed and studied. Llithium battery failures mainly occur in the positive electrode,negative electrode,separator,organic solvent,welding end and housing. Then the failure modes and failure mechanisms of each part are analyzed,and their respective phenomena are given. The lithium battery must be tested according to the requirements of the charge and discharge parameters of corresponding specifications,and the lithium battery with the positive temperature coefficient（ PTC）thermistor protection and without the PTC thermistor protection must be tested separately during the leakage test. Finally,the LG18650 lithium battery is tested,and the correctness of the above analysis is verified.