锂离子电池失效分析概述

Overview of the failure analysis of lithium ion batteries

商业化的锂离子电池在使用或储存过程中常出现某些失效现象,包括容量衰减、内阻增大、倍率性能降低、产气、漏液、短路、变形、热失控、析锂等,严重降低了锂离子电池的使用性能、一致性、可靠性、安全性。这些失效现象是由电池内部一系列复杂的化学和物理机制相互作用引起的。对失效现象的正确分析和理解对锂离子电池性能的提升和技术改进有着重要作用。锂离子电池失效分析是以电池的失效现象为起点,针对该现象选择适当的测试分析手段,设计合理、有效的失效分析流程,挖掘电池在材料制备和制造工艺层面上的失效主要原因,并能提供相关可靠有效的优化建议。本文综述了锂离子电池的失效现象及其失效机理、失效分析常见的测试分析方法、失效分析流程的设计,并列举了容量衰减、热失控和产气等方面相关分析案例进行说明。

The failure problems, associated with capacity fade, increased internal resistance, gas generation, electrolyte leakage, short circuit, battery deformation, thermal runaway, lithium deposition and etc., are the major issues that limit the performances, reliability and consistency of the commercialized lithium ion batteries. These problems are the result of a complex interplay of a host of chemical and physical mechanisms. A reliable analysis and fundamental understanding of aging characteristics is of critical significance for development of battery. The failure analysis of lithium ion batteries is started with the identification of the failure effects, then selected the advisable analysis methods to establish the high efficiency procedures to target the problems and thus to find out the primary causes as well as to provide reliable suggestions for further optimization of material fabrication and battery engineering. This article discusses the failure effects and their causes in lithium ion batteries. The procedure of the failure analysis and the inspection methods will also be presented. Some cases of failure analysis are reviewed in this manuscript, such as capacity fade, thermal runaway, and gas generation.