Performance Evaluation of a Parallel Air-Cooled and Water-Cooled Battery Pack

This work aimed to evaluate the performance of air-cooling and water-cooling systems designed for battery pack holders. Battery holder was planned to be placed in a closed container, contained of 112 LFP batteries, arranged in 4 modules and vertically stacked. Each module consisted of 28 LiFePO4 cylindrical batteries. Fourteen copper cooling pipes were mounted vertically to absorb the dissipated heat during the charging or discharging process. Cooling media entered from the manifold at the bottom of the container and left at the top of the container. In this work, the cooling system was evaluated for one one-through system, with an inlet cooling media temperature of 303.15 K. Varied charge and discharge current, from 1C to 7C were set in this work. The results showed that cooling air was not feasible for dissipating heat for more than 1C current. The water-cooled system was able to remove heat up to 7C current, with the Water as cooling media performing better as water may dissipate released heat when the battery runs up to 7C. At an optimum linear velocity of the cooling water, the overall heat transfer coefficient value, evaluated at an optimum linear velocity of water, the value of clean overall heat transfer coefficient was 706.37 W/m2.K. Minimum and maximum dirty overall heat transfer coefficients were 9.72 W/m2K and 476.21 W/m2.K. Minimum fouling factor of the designed water cooling system was 0.0007 m2.K/W.