Thermal Management of EV Battery Pack: Evaluating the Cooling Strategy with Air Convection

The study presents a thorough theoretical analysis of the thermal distribution in electric vehicle battery packs under different heating loads. A finite-element heat transfer model is developed in COMSOL to simulate a battery pack with 15 cylindrical lithium-ion cells integrated with liquid-cooled support plates. C-rates, which define heat generation during the charge-discharge cycle, are included in the model-in real case scenarios wherein a 10 Ah battery generates heat outputs of about 10.5 W, 25 W, and 54 W at 3C, 5C, and 8C charge rates, respectively. Transient simulations display how the temperature profiles evolve with time and reach quasi-steady states by which heat input is counterbalanced by heat dissipation through convection. It also examines air convection performance as a technique for cooling, revealing that while it is cheaper and simpler to implement, the technique is less effective than liquid cooling. Other alternatives in this regard, such as the use of graphite foam, have been investigated concerning their ability to achieve higher heat transfer coefficients, thus enhancing thermal load management at greater rates of charge. The results illuminate the importance of optimized thermal management systems to avert thermal runaway for EV battery packs and ensure their safety, efficiency, and longevity. The work provides insights useful in designing and improving cooling strategies for next-gen electric vehicles.