Thermal Analysis of Lithium Ion Battery Pack with Different Cooling Media

Prediction of cell characteristics and its thermal behavior is critical to design and optimize thermal management system for electric vehicle battery pack. In the present paper experimental and numerical study is carried out to characterize the thermal behavior of electrochemical cell under constant discharge rate. 3D numerical model is developed for 18650 lithium-ion cylindrical cell. Average temperature of single cell and cell pack is estimated for a constant discharge rate. Air and naphthenic oil at 298K is considered as working fluid. The result shows a significant reduction in battery module cell average temperature of 6.6 ℃ for 1C discharge and 9.8 ℃ for 2C discharge using oil as compared to air. Present numerical results are validated with experimental study for a single cell and 3 × 3 battery module under natural convection and are found to be in good agreement.