Modeling an Electric Vehicle Lithium-Ion Battery Pack Considering Low Temperature Behavior

This paper deals with the modeling and simulation of an electric vehicle lithium-ion battery pack considering low temperature behavior. The initial part is focused on the impact of considering the thermal dynamics. To this end, experimental data is used to evaluate the parameters behavior due to the operation at low temperatures. The second part is devoted to study the thermal distribution in the complete pack. In this analysis, the advantage of using a structural approach such as Bond Graph becomes crucial. The complete thermal model is obtained graphically thus creating a direct correspondence between the topology of the system and its representation. Simulation results are provided in order to illustrate the importance of considering the thermal dynamics and the degradation produced when the cells within the battery pack are not equalized.