Recent Progress on Mechanism of Mechanical Abuse 2024-01-2405

With the rapid development of electric vehicles (EVs), lithium-ion batteries (LIBs) with high energy and power density have been widely applied as the power producer of EVs. However, the range of EVs has been criticized. To meet consumer demand for high power and long driving distances, the energy and power density of LIBs are getting higher and higher. However, LIBs with higher energy density are more prone to catastrophic thermal runaway (TR). In recent years, EV accidents due to TR of LIBs have been frequently reported, which makes consumers lose confidence in EVs. To solve the problem, we must understand the mechanism of LIBs TR, thereby reducing the likelihood of TR in EVs. However, the induction mechanism of LIB TR induced by mechanical abuse is sophisticated. This paper focuses on recent advances in the study of thermal TR characteristics of batteries caused by mechanical abuse, including bending, collisions, and penetration. The impact of various mechanical abuses on the TR characteristics of batteries has been summarized. From the onset of mechanical abuse conditions to the occurrences of TR, the interior evolution of the battery is discussed through experiment and theory, to reveal the processes of mechanical deformation and internal short-circuit (ISC) of LIBs. Additionally, an acceleration calorimeter and X-ray computed tomography (CT) are used to investigate the TR process and the evolution of temperature, voltage, and structure of battery components in the battery under mechanical abuse conditions. This paper aims to summarize the latest progress in the study of the mechanism of mechanical abuse-induced battery TR, to help engineers design safe batteries.