Comprehensive Performance Evaluation Strategy for Power Battery System based on Dynamic Weight

Abstract

New energy vehicles are the effective solution to solve the situation of carbon neutrality with carbon peaking in China. The power battery system is the key component of new energy vehicles, and its performance is directly related to the safety and cruising range. Since the performance of the battery system is affected by factors such as electrical contact stability, voltage and current characteristics, and its own temperature, its full life cycle performance cannot be comprehensively evaluated, resulting in the inefficient prediction and protective measures. In this paper, the electrical contact stability evaluation index is proposed by studying the relationship between the electrical contact stability and the fluctuation characteristics of the reversed equilibrium potential. The parameters including electrical contact stability, polynomial-based status of charge (SoC), the status of health (SoH), the status of consistency, as well as battery system temperature constituted the performance matrix of the battery system. A comprehensive performance evaluation method of power battery system based on dynamic weight is designed with normalized classification. Finally, the cyclic charge-discharge test experiment under the vibration status were carried out to verify the effectiveness of the method. The result showed that the method can characterize various functions and provide an intuitive and detailed evaluation for the safety prediction of battery system.