A crucial component in the development of the battery management system (BMS) is the establishment of an accurate battery equivalent model. The dynamic properties of the battery can be precisely described by the second-order RC equivalent circuit model. Through battery performance test experiments, the battery model parameters in charging and discharging states are identified separately, taking into account the influence of state of charge (SOC) and battery charging and discharging state on the model parameters. Using the Simscape programming language, an equivalent circuit model of a lithium-ion battery with changeable parameters is created, and simulation analysis is performed. The findings demonstrate that the model's accuracy is increased and its error is minimal when the impact of battery charge and discharge state is taken into account.

A crucial component in the development of the battery management system (BMS) is the establishment of an accurate battery equivalent model.