Abstract:At present, the operating conditions of the power management system is poor, which can not be adjusted in real time for the current road conditions, reducing the cycle life of the battery. According to this problem, this paper proposes a kind of power management system with capable of switching battery group based on single chip microcomputer. In this system, the discharge voltage and current are used as the correction, and the EKF algorithm is adopted to improve the accuracy of SOC estimation. Experiment shows: The accuracy of the design of the acquisition module can be verified by using the single battery discharge test. Then using Simulink to simulate the working condition, the accuracy of SOC estimation is verified.According to the different operating conditions, the system automatically switches the reliability of the battery group.