SOC Estimation of Lithium Battery Based on Fuzzy Kalman Filter Algorithm

Aiming at predicting problem for the charged state of lithium batteries in electric vehicles(EV), an algorithm derived from fuzzy extended kalman filter is proposed on the basis of large estimation deviation of traditional methods. A second-order RC equivalent circuit model combining Thevenin and RC network is established to recognize the parameters for the battery model.A fuzzy controller is added into the traditional kalman filter algorithm to evaluate the state of charge (SOC) for battery from this paper. Using Matlab to verify, as well as the simulation results indicate the improved way enhances the accuracy of the estimated SOC.