Thermal runaway characteristics on NCM lithium-ion batteries triggered by local heating under different heat dissipation conditions

Abstract

Thermal runaway is the most important safety problem of the lithium ion battery. A thermal model combined five side reactions is established to analyze the temperature distribution change of the separator and thermal characteristics during the thermal runaway process of a lithium-ion battery cell with local heating cathode current collector surface under different heat dissipation conditions in this paper. The results show that when the heat dissipation coefficient of the battery reaches 10 W/(m2 K), it can effectively control the occurrence of battery thermal runaway, but the temperature distribution uniformity of the separator surface becomes worse. As the heating temperature and heating area of the battery increased, the consumption rate of the material increased, but the maximum temperature rise and the type of side reaction did not change. This can effectively guide the design of the battery thermal management system.