Comparative analysis of thermal runaway characteristics of lithium‐ion battery under oven test and local high temperature

Summary Lithium‐ion batteries are increasingly used in the field of new energy vehicles. Thermal runaway is the biggest potential safety hazard. In order to achieve safer battery and battery design, it is necessary to fully understand thermal runaway. In this paper, the thermal abuse model of lithium‐ion battery is established, and the accuracy of the model simulation is verified through experiments. The thermal runaway characteristics of the battery under the oven test and local heating conditions are compared and analyzed. The results show that under the condition of 200°C oven test in more than 10 000 seconds to thermal runaway, the local heating under the condition of the thermal runaway in more than 500 seconds, and the oven temperature distribution more uniform on the surface of the test under the condition of the battery, the temperature distribution is almost consistent when thermal runaway. According to the characteristics of local heating mode, the small heating area cannot occur thermal runaway, and found that in the process of thermal runaway battery anode and electrolyte reaction to generate heat is the main cause of thermal runaway battery. This result can be used to guide the effective prevention of thermal runaway of lithium‐ion batteries and prevent spreading.