A Comparative Study on Cylindrical and Prismatic Lithium-Ion Batteries: Thermo-Hydraulic Performance and Entropy Generation Analysis for Efficient Cooling

In operating a vehicle powered by electric batteries, thermal management plays a vital role in efficiency and safety. In this numerical study, the thermo-hydraulic performance and entropy generation analysis of cylindrical and prismatic cell battery packs with similar voltage, capacity and discharge specifications are carried out. Three configurations of cylindrical cell battery packs with cells in aligned, staggered and circular configurations are studied for various Reynolds numbers (Re) and the same are compared to the prismatic cell battery pack. The results showed that the prismatic battery pack has the lowest maximum temperature in the range of 315 to 304 K compared to the cylindrical cell battery pack with 322 to 310 K. Owing to uniform and lower temperature gradient, the prismatic cell battery pack has lower irreversibility leading to higher heat transfer rate. With smaller recirculation zones and the absence of stagnation points upfront, the pressure drop in the prismatic cell battery pack is significantly lower. Subsequently, higher thermo-hydraulic performance is obtained for prismatic cell battery pack cooling. Owing to lower thermal and fluid friction irreversibility, the entropy generation in the prismatic battery pack is the lowest.