Numerical Investigation on Thermo-Hydraulic Performance of a Micro-channel Liquid Cooled Battery Thermal Management System

Abstract

An effective Battery Thermal Management Systems (BTMS) is essential for maintaining optimal temperature conditions within lithium-ion (LiFePO4) battery packs, thereby ensuring the battery's optimum performance, enhanced cycle life, and safety. Among various cooling methods, liquid cooling stands out as the preferred choice for BTMS. This study introduces a novel liquid-cooled system integrated with micro-channels within the battery casing. The impact of operating parameters (Reynolds Number (Re) and mass flow rate) on the 10 cylindrical LiFePO4 battery pack (21700 type) has been studied numerically and theoretically. The investigations revealed that as the Re increases from 400 to 700 the battery pack’s maximum temperature (Tmax) decreases from 42.06°C to 40.61°C, and the temperature difference (ΔTmax) decreases from 2.45°C to 1.94°C. Also, the coolant outlet temperature decreases from 38°C to 35°C, while the pressure drop (ΔP) increases from 3410 Pa to 3990 Pa. The use of micro-channels in the BTMS resulted in significant coolant conservation, saving the coolant ∼76% and the convective heat transfer coefficient (CHTC) showed an approximately 125% increase in comparison to previously published studies on both mini-channels and macro-channels.