Advancements in the safety of Lithium-Ion Battery: The Trigger, consequence and mitigation method of thermal runaway

With the escalation of environmental issues, the large-scale application of lithium-ion batteries (LIBs) has become a prominent solution to replace the use of fossil fuels. However, safety issues related to LIBs, particularly thermal runaway (TR) and its propagation, have yet to find robust solutions. This has impeded the application of LIBs in electric vehicle (EVs) to some extent. In this review paper, the factors triggering TR in LIBs, the consequences of TR and the current available methods for mitigating TR are summarized. More specifically in the first part, the major causes of LIB thermal runaway are examined from three primary triggering factors, including mechanical abuse, electrical abuse and thermal abuse. The causation of TR is summarized comprehensively combined with internal short circuit (ISC) and some minor contributing factors. Furthermore, a specific phenomenon called 'spontaneous ISC' has been detailed and analyzed. Secondly, the consequence of TR is analyzed from the perspective of exhaust, jet fire, heat release. Lastly, an analysis and categorization of existing thermal runaway propagation (TRP) control methods for LIBs are conducted from the perspectives of active control and passive control. This paper also provides a comparative summary of control and improvement techniques of battery TR.