Error analysis for lithium-ion battery parameterization in cell cycle lifespan

An improved electrical equivalent circuit (EEC) model combining the slow and fast dynamic behaviors of Li-ion battery is proposed based on Thevenin theory. Recursive least squares (RLS) algorithm is used to calibrate model parameters by means of the hybrid-pulse-power-characteristic dynamic test. The nominal model identified has good accuracy in capturing the dynamics of the fresh battery. The modeling uncertainty, however, increases, as the battery ages. Error analysis is carried out at different degradation levels in the battery lifetime, in order to quantify the aging effect on the battery dynamics and thus voltage behavior.