New concept of hybrid cooling system for fast charging of electric vehicles

The adoption of electric vehicles (EVs) with lithium-ion (Li-ion) batteries is steadily increasing. The performance, efficiency, and safety of Li-ion batteries rely significantly on thermal management systems (TMSs). This study investigates a novel hybrid TMS, combining aluminum plate, phase change material (PCM), and liquid cooling, to cool the battery module. A passive PCM heat buffer plate and liquid cooling plates are strategically positioned, with the former placed below and the latter on the sides. The temperature of the module has been considered under the 4C and 8C charging rates and using different cooling methods. Natural convection cooling alone fails to maintain the module temperature within the desired operational range during fast charging. The maximum module temperature during charging for 4C and 8C peaks at 42 degrees C and 58.5 degrees C, respectively. However, incorporating a PCM heat buffer plate reduces temperatures to 36.3 degrees C and 49 degrees C by the end of charging, marking reductions of 13.5 % and 16 %, respectively. With the hybrid cooling system, temperatures further drop to 31.2 degrees C and 38.4 degrees C by the end of charging, representing reductions of 25.7 % and 34.3 %, respectively, compared to natural convection.