A method of SOC estimation for power Li-ion batteries based on equivalent circuit model and extended Kalman filter

Abstract

With the rapid development of new energy industry, Li-ion batteries have been widely used around the world, especially in electric vehicles. In order to improve the performance of Li-ion batteries and ensure their safety, the battery management system (BMS) needs to obtain accurate state of charge (SOC) estimation. In this paper, a new method is proposed based on equivalent circuit model and extended Kalman filter (EKF). Firstly, the behavior of battery is analyzed based on equivalent circuit model. Then SOC is estimated by EKF algorithm. At last, the method is validated through experiment.