Study on Thermal Runaway Behavior of Lithium Ion Battery under Overcharge Using Numerical Detecting Method

Abstract In order to provide support for the early warning model of thermal runaway of lithium-ion battery, the thermal runaway behavior of power lithium battery is studied by analyzing the charging current, voltage and other parameters of lithium-ion power battery under overcharge condition. In addition, the morphological changes of battery before and after thermal runaway are compared. It is found that under the conditions of this study, overcharging for 58 minutes will lead to thermal runaway of full load lithium-ion battery. In the early stage of thermal runaway, the leakage gas in the battery box will continue to increase, which is 1339 ppm in the First Level early warning, 3405 ppm in the Second Level early warning and 8292 ppm in the Third Level early warning.