Thermal Characteristics of a Lithium-ion Battery used in a Hybrid Electric Vehicle under Various Driving Cycles

Lithium-ion battery is the most preferable type for hybrid electric vehicle due to their superior performance. The battery performances and safety factors are influenced by its operating temperature, hence it needs to be controlled carefully. Battery has a good performance at high temperature but this put it at risks of thermal runaway and explosion. This study presents a simulation model to predict battery's thermal behaviours during discharging and charging through regenerative braking in a series hybrid electric vehicle under various driving cycles. In total, five driving cycles are covered namely New European Driving Cycle (NEDC), Artemis cycle, Japanese 10-15 Mode cycle, FTP-75 cycle and worldwide harmonised light vehicles test procedure cycle. Validation of the model is performed using experimental results for NEDC cycle. Important results presented in this study focus on the battery temperature under different driving cycles and the impacts by considering thermal generation during charging process. Even though the temperature increase is relatively small, but the contribution of heat generation during charging is significant especially in an aggressive driving cycle. These results are very important in providing better understanding on the battery thermal behaviours so that a more effective battery management system can be developed (199/200).