Optimizing the Heat Dissipation of an Electric Vehicle Battery Pack

Battery packs are critical components to electric vehicles. They are designed to last for the designed life cycles. Temperature affects the performance and life span of batteries. Maintaining stable and evenly distributed temperatures within the operating temperature range among all modules and battery cells is one of key factors to prolong the life of battery packs. This paper studied the effects of the ventilation locations of the inlets and outlets and the gaps among battery cells on the rate of heat dissipation and temperature distribution in the pack. An existing battery pack was used as a baseline design. A computational fluid dynamics model was created to analyze the temperature distribution and air flow conditions. The design intent is to keep the package changes to the minimum but with better cooling efficiency. The results show that the locations and shapes of inlets and outlets have significant impact on the battery heat dissipation. A design is proposed to minimize the temperature variation among all battery cells. The temperature difference between highest and lowest ones for the evaluated event is reduced from 6.04 degrees C to 3.67 degrees C with 39% improvements, and the heat dissipation rate is improved with 3.8%.