Experimental and numerical investigation of the usage of air diverter fins on temperature of prismatic li-ion battery for different operation conditions

Nowadays, electric vehicles stand out more than vehicles with internal combustion engines since electric vehicles are environmentally friendly and highly more efficient. Electric vehicles usually consist of a large-volume battery pack, electric motor and regenerative braking system. Selection and thermal management of the battery, which is one of the most important equipments that constitutes electric vehicles, are important. Researchers are trying to keep the operating temperature of the batteries at the desired level (20°C-40°C) with many different techniques such as air, liquid, phase change material and hybrid thermal management systems. In this study, the thermal management of a 20 Ah pouch-type prismatic lithium-ion battery used in electric vehicles was investigated experimentally and numerically. Air was used as the fluid, and the fluid inlet temperature (15°C, 25°C, 35°C), fluid inlet velocity (0,5 m/s, 1 m/s, 1,5 m/s) and discharge rate (2C, 3C, 4C) on the battery surface temperature, the battery surface temperature difference and the heat transfer rate were investigated. It was observed that the surface temperatures of the battery increased with increasing discharge rate and air inlet temperature, while the surface temperatures of the battery reduced with increasing air velocity. With the use of air diverter fins, improvements were observed in the average battery surface temperature up to 6,35°C and more homogeneous temperature distribution was achieved on the battery surface.