Review of Thermal Runaway and Safety Management for Lithium-ion Traction Batteries in Electric Vehicles

Abstract：Lithium-ion battery is considered to be the most promising type of traction battery of electric vehicles (EVs) for its high energy density, long cycle life and no memory effect.With the continuous improvement of energy density of lithium-ion batteries and the reduction of manufacturing costs, the safety accidents characterized by thermal runaway have occurred frequently, which seriously threatens the safety of passengers' lives and property.Therefore, the issue of lithium-ion battery thermal runaway has become a research focus in the field of EVs.Meanwhile, the development of related fields also needs the guidance of such review articles.From a safety point of view, a comprehensive overview of current state of thermal runaway within lithium-ion batteries used in EVs is summarized, as well as the latest research results.Moreover, the trigger and failure mechanisms of thermal runaway are clarified, and the methods to improve the safety of lithium-ion power battery system are summarized comprehensively, with the aim of promoting the development of safety management methods and strategies for advanced lithium-ion battery systems and improving the safety of traction battery systems.The gap of the lack of Chinese review papers is filled in this field.