Reliability Prediction of Battery Management System for Electric Vehicles Based on Accelerated Degradation Test: A Semi-Parametric Approach

The Li-ion battery has emerged as the most prominent energy storage device and been widely applied in electric vehicles (EVs). To ensure the safety and performance of batteries, a battery management system (BMS) is incorporated in the EVs. However, how to predict and verify the BMS reliability remains an issue. We conduct the accelerated degradation test on the BMS and develop a semi-parametric framework to predict the reliability. A new measure based on similarity is further proposed for model comparison. A real data set of the BMS is used to verify the validity of the proposed method. A comparison with the other four models shows that our approach can generate a more similar trend to the original data, with 39.23% improvement compared with the best-performed model based on the proposed measure. Besides, the proposed model gives a prediction of lower bound of the reliable lifetime as 10.8 years, which is more reasonable compared with the results (i.e., around one year) given by the conventional models.