HEV thermal management of high voltage battery with indirect air cooling and regarding customer performance

Sammanfattning: The automotive environment is quickly evolving due to increasingly stringent environmentalstandards and the gradual reduction of the volume of diesel motorized vehicles. The volumes of electrifiedvehicles are thus constantly growing and are brought to be more and more present in our streets. Thiselectrification of vehicles involves new specifics issues compared to conventional vehicles, depending on thedifferent levels of electrification, which includes notably Hybrid Electric Vehicles.Hybridization in cars is characterized by the addition of a electrical traction and/or electrical generation systemin addition to the conventional thermal engine. However, if the complexity of vehicles with thermal tractioncomes essentially from the internal combustion engine and its efficiency which are sometimes complex tooptimize, the complexity of electric traction is expressed on the other hand at the level of the battery whichsupplies high voltage electricity. Indeed, while an electric machine offers high efficiency and an easy control,the high voltage battery contains many issues linked to a complex chemistry which must be controlled, andcan be subject to overheating.This overheating phenomenon is particularly an issue on HEV, which have smaller batteries than BEV and PHEVapplications for a comparable power demand. The conception of an efficient high-voltage battery coolingsystem is therefore essential in order to avoid any danger of damaging the system or potential fires linked tothe overheating of the battery. The air cooling solution is the most common, but this could change with thenew standard of the Electric Vehicle Safety Global Technical Regulation (EVS-GTR) applicable in 2021prohibiting the rejection of the cooling air that was in contact with the battery cells inside the passengercompartment. Is this solution able to adapt in order to remain competitive with the water or air conditioningcooling solutions? This study's purpose is to bring an answer to this issue.