Accuracy state of charge estimation used in energy storage system for electric transportation

Electric transportation is the development tendency of the transportation systems in future world. Energy storage systems are the key components of the electric transportation systems. Accuracy state of charge (SOC) estimation of energy storage system is crucial not only for improve energy used efficiency, but also for electric transportation drive safety. This paper choose LiFePO4 Li-ion battery as energy storage medium, use equivalent circuit modeling the battery, estimate the SOC of the battery through SMFEKF algorithm. The comparison between the SMFEKF algorithm simulation data and the experimental data shows that the SMFEKF algorithm has a better accuracy in SOC estimation.