Power Battery Fault Diagnosis Based on Probabilistic Analysis

Abstract

With the development of new energy vehicles and the increase in their ownership, the safety problems of new energy vehicles have become increasingly prominent, and incidents of spontaneous combustion and self-detonation are common, which seriously threaten people’s lives and property safety. The probability analysis model of battery failure of a power battery unit is established according to the normal working range of power battery parameters. Through the real-time monitoring of the working parameters (T, V, I) of the battery unit, calculate the probability value of each parameter that may trigger the corresponding fault. Based on the Analytic Hierarchy Process (AHP) method, calculate the weight of each parameter on the safety of the power battery. In the electrical safety analysis, the temperature weight is 0.65, the current weight is 0.23, and the voltage weight is 0.12. The calculated weights are assigned to the probability values calculated for each parameter to calculate the probability of battery failure, which also indicates the degree of danger in the state of the battery. This method can be used to determine whether a fault has occurred or is about to occur by extrapolating the fault rate from the real-time data of the power battery unit, which has a positive effect on the effective prevention of safety accidents caused by power batteries.