Study on the Charging and Discharging Model of Ni/MH Battery Module for Electric Vehicle

Abstract

The parameters of the battery model are time varying because the influence of the State of Charge (SOC). It is difficult to determine the relation between the parameters of the battery model and the SOC. In this paper, the mended equivalent circuit model is adopted and the time-varying parameters of which are estimated based on the fuzzy inference according to the fuzzy input SOC. So the accuracy of the model is improved and the requirement of the estimation accuracy of SOC is reduced. The results of the simulation test show that the maximum absolute error of the loaded voltage of the Ni/MH battery module is 0.04V and the relative error is 0.28.