SOC estimation based on the model of NI-MH battery dynamic hysteresis characteristic

Accurate estimation of battery State of Charge (SOC) is essential for battery control and effective energy management of Hybrid Electric Vehicles (HEV). Taking the dynamic hysteresis characteristic of battery into account, an equivalent circuit model is built. Based on the Hybrid Pulse Power Characterization (HPPC) test data, the parameters was adopt by means of on-line least-square regression. The accuracy of SOC estimation algorithm was verified by the energy balance test, the energy consumption test, New Europe Driving Cycle (NEDC) test and real vehicle driving cycle test, respectively. The experimental results show that this method is with high accuracy and reliability.