Design and Analysis of Liquid-Cooled Battery Thermal Management System of Electric Vehicles

The thermal management of lithium-ion batteries plays an indispensable role in preventing thermal runaway and cold start in battery-powered electric (BEV) and hybrid electric vehicles (HEV) during on-road or fast charging conditions. The functioning of a battery depends on its thermal behavior. The life cycle and charging speeds are the optimizing factors of an EV battery pack. Higher charge rates translate to higher heat generation. At higher temperatures, it delivers an increased charge capacity but reduced longevity. But at lower temperatures, there is a higher electric resistance leading to lower efficiency and reduced total capacity of the battery. So the battery must be run at an optimal temperature range of 22–30 ℃ to improve performance and maintain its state of health (SOH). With the current battery technology, a battery pack is incomparable to gasoline in terms of energy density. So for an equivalent battery pack, the packing efficiency of the cylindrical battery assembly must be high, while preventing heat accumulation during high charge–discharge operations. Asymmetric thermal distribution can cause variation in the current discharge and the cell operating behavior, so a BTMS based on the thermal nature of the cells is designed. In this paper, we study the effects of a tab cooling BTMS on an anisotropic battery arrangement at different charge–discharge cycles.