Abstract: Abstract: Analyze the information of electric vehicle fire accidents in 2018-2021, and summarize the typical characteristics of electric vehicles on fire. Origin was used to analyze the operating parameters data of electric vehicle fire BMS, and found the typical characteristics of the operating parameters (SOC, voltage, temperature, insulation resistance, etc.) caused by the water ingress of the battery pack and the fault of the power battery (thermal runaway of the battery cell and the fault of the line in the battery pack). Based on this, a judgment model of electric vehicle fire cause based on operating parameters is constructed by using neural network method, with 12 operating parameters as input information and 3 types of fire causes as output information. The model reached the expected error level of 0.05 through training, and the correctness rate of the test sample reached 100%, which proved the reliability of the model. The results show that the operating parameters of electric vehicle fire accidents of different causes have different characteristics and laws, and the use of cause discrimination model can effectively assist in determining the cause of electric vehicle fire.

Key words: Key words: electric car fire, cause of fire, BMS parameters, the neural network