Numerical study and comparison of heat transferring ability of geometrically modified lithium-ion cells for battery packs

The growth in electric vehicles is climbing so is the requirement of battery packs. Most commonly used battery packs are made of cylindrical lithium-ion (Li-ion) cells arranged a specific orientation. For a highly effective cooling system of a Li-ion battery pack, an appropriate cell arrangement plays a substantial role. In electric vehicles, the battery pack decides the performance of it, as it is the only power source. Under extreme temperature conditions, the efficiency of the battery packs decreases. This non-uniform effect must be minimized by recommending the appropriate location and orientations of cells. Hence, the battery pack is modeled and analyzed for both inline and staggered arrangements in this study. The numerical simulations are carried out using Ansys Fluent-18. Moreover, this paper also explores the possibilities of using cells with an elliptical cross-section and its effect on cooling performances and recommendations have been made. It is found that the pressure drop decreases by five times when the circle is replaced by an ellipse. The pressure drag decreases when the ellipse is placed in a staggered arrangement and is found to be 72.63% with respect to inline arrangements. Though the flow characteristics were in favor of the ellipse, the heat dissipation was found to be better for circular cells.