Abstract

In this paper the parameterization of an integrated electro-thermal model for an A123 26650 LiFePO4 battery is presented. The electrical dynamics of the cell are described by an equivalent circuit model. The resistances and capacitances of the equivalent circuit model are identified at different temperatures and SOC’s, for charging and discharging. Functions are chosen to charac-terize the fitted parameters. A two-state thermal model is used to capture the core and surface temperatures of the battery. The electrical model is coupled with the thermal model through heat generation. Parameters of the thermal model are identified us-ing a least squares algorithm. The electro-thermal model is then validated against voltage and surface temperature measurements from a realistic drive cycle experiment. 1