Investigation on thermal performance analysis of a pouch Li-ion battery under various drive cycle profiles

Knowledge of accurate battery temperature is essential for enabling safe operation of batteries in electrified vehicles application under aggressive drive profiles. Thermal modelling of batteries based on mere joule heating term is usually unable to compensate for resulting inaccuracy due to neglecting entropic heat in batteries. Inclusion of entropic effect into the thermal model derived from simple experiments can help accurate estimate of battery temperature in early design stage. This paper presents a lumped thermal model incorporating entropic effect to predict transient thermal behaviors of pouch cell under various aggressive loads. Compared with experimental results simulation model can predict results with acceptable accuracy and minimal computing cost. The simulation results with these tested conditions are found in good agreement with experimental results with a maximum RMSE error of 0.15, 0.07, 0.29, and 0.26 respectively. This shows the inclusion of reversible heat in the enhancing thermal prediction performance of the proposed electro-thermal model is significant and is a fairly good candidate for a rapid electro-thermal simulation of Li-ion pouch type batteries.