Optimized Thermal Management of Cylindrical Lithium-Ion Batteries Using Circular Fins and Forced Air-Cooling

The Battery Thermal Management System (BTMS) is vital for maintaining the optimal performance, safety, and longevity of electric vehicle batteries by keeping their temperature within a desired range. This study proposes an optimized cooling solution for BTMS based on both experimental and numerical investigations. Experimental tests were performed on a single battery cell under discharging rates of 1C, 2C, 3C, and 4C using an electronic load, with thermal performance evaluated under natural convection. Numerical models simulating both forced and natural convection were developed using ANSYS 19.3, and a combined Computational Fluid Dynamics (CFD) and Response Surface Methodology (RSM) approach was applied to optimize a finned BTMS under constant heat generation. Key parameters such as inlet air velocity (Vi), inlet air temperature, fin number, and fin thickness were analysed for their effects on maximum temperature (Tmax), system weight, and pumping power. Results showed that increasing air velocity (V) and decreasing air temperature reduced maximum battery temperature by 42.03°C (about 40.5%) and 16.07°C (about 23.9%,) respectively, while adding fins further reduced it by 18.76 °C (about 19.4%) (with optimum fin number) and 10.16 °C (about 12.15%) (with optimum fin thickness). The optimized configuration achieved an overall 11.9% reduction in (Tmax), with a corresponding 14.1% increase in system weight.