The effort to curb emissions and climate change drives automobile manufacturers away from fossil fuels toward electric power. In an electric vehicle (EV), the lithium‑ion (Li-ion) battery pack serves the purpose of the fuel tank, and the cells are safest and perform most efficiently when they operate between about 25 °C and 45 °C. When operated outside this range, they lose performance, shorten battery life, or risk catching fire due to unwanted side reactions in the cell. This study uses face- and side-cooling strategies to present lightweight, liquid-cooled thermal management solutions for pouch-type battery packs. Instead of cooling the entire cell surface, which is followed conventionally, infrared imaging (IR) is used to identify hotspots in the cell. Based on insights from IR analysis, a novel T-shaped cold plate (TCP) is designed and experimentally tested for targeted face cooling, reducing system weight while keeping cell temperatures below 45 °C.. A new graphite-insulation sheet (GIS) has been developed for side cooling. Experimental investigations showed a superior cooling performance compared to the standard insulation sheet. These solutions offer efficient, lightweight, and thermally effective EV battery thermal management options. The study also explores the immersion cooling techniques with environmental free dielectric fluids. This study also presents a hybrid machine learning framework for reconstructing full-field surface temperature distributions of lithium-ion pouch cells using sparse thermocouple data.
To address the thermal limitations of conventional air and indirect liquid cooling, direct immersion cooling is emerging as a highly effective alternative, as it completely avoids thermal contact resistance by placing the coolant in direct contact with the cell surface. This study explores single phase immersion cooling for high capacity 60 Ah lithium-ion pouch cells using two environmentally friendly synthetic dielectric fluids are AmpCool AC-110 and Thermasolv IM-7. The experimental methodology evaluates two primary configurations: natural convection, where the cell is submerged in a stagnant fluid pool, and forced convection, where the dielectric fluid is actively circulated around the cell through an inlet and outlet. Evaluating the temporal variation in the cell’s maximum temperature reveals the profound impact of forced fluid flow. While natural convection provides a baseline of cooling, actively circulating the dielectric fluids significantly suppresses the temperature rise over the duration of the discharge cycle. By introducing specific flow rates, the dielectric fluids efficiently transport heat away from the cell, keeping peak temperatures much closer to the safe 45 °C operational limit even under demanding high-discharge conditions.
