Li-ion batteries SOC observation method based on model with variable parameters

In this paper, the research on the observation method of state of charge (SOC) of the Li-ion battery is carried on aiming at the current problems of the low precision of the SOC observation results, an accurate and efficient SOC observation method is designed for Li-ion battery based on a 2
^nd
-order RC model with variable parameters. Firstly, the A Amper-Hour (AH) integral estimator is built according to the definition of SOC, and then the Extended Kalman Filter (EKF) estimator is established by introducing the EKF principle; Then, combined with the Takagi-Sugeno fuzzy principle, the TS-EKF union estimator is eventually designed. Finally, the accuracy and the practicability of the SOC observation method with the core technologies are verified based on the simulation platform of Simulink.