Computational Fluid Dynamics-Based Numerical Analysis for Studying the Effect of Mini-Channel Cooling Plate, Flow Characteristics, and Battery Arrangement for Cylindrical Lithium-Ion Battery Pack

Battery Thermal Management System (BTMS) is crucial to maintain peak temperature and temperature difference of lithium-ion battery pack in appropriate range, thus ensuring best performance, extended cycle life and safety. Liquid cooling BTMS is extensively researched for prismatic cells, but only a few studies are present on application of liquid cooling BTMS for cylindrical cells. Further, existing studies on liquid cooling for cylindrical cells majorly focus on effect of flowrate, flow direction, and number of channels. In this study, a novel mini-channel cooling plate-based liquid cooling BTMS is proposed for a battery pack of 20 cells. Computational fluid dynamics (CFD)-based numerical analysis was performed on three-dimensional model of battery pack to investigate effects of parameters associated with cooling plate and mini-channel design, flow characteristics, and battery arrangement on temperature uniformity, heat removal rate, parasitic power consumption and weight of the battery pack. The study concluded that installation of aluminum cylindrical enclosure on cells could drastically enhance heat removal and temperature uniformity. Altering flow directions in mini-channel could enhance thermal performance. The research demonstrated that for case 2d (inlet and outlet are staggered in each cooling plate), the temperature difference can be reduced by 16.5% when compared to unidirectional flow. Mini-channel with square cross section offers better heat removal and fewer flow resistance compared to circular and elliptical. Although converging mini-channels offer better thermal performance, it drastically increases the pumping power. The battery pack was successful in limiting peak temperature and temperature difference to 303.26 K and 1.98 K, respectively, for 4 C discharge rate.