Air cooled lithium-ion battery with cylindrical cell in phase change material filled cavity of different shapes

The present study numerically investigates the effects of phase change materials (PCMs) in chambers of different shapes on the thermal management of cylindrical Li-ion batteries (CLIB). A battery cell in a PCM-filled chamber inside an air-cooled system was simulated two-dimensionally in a transient state. An Organic PCM with graphene nanoparticles (NPs) was employed. Square, circular, triangular, lozenge, and hexagonal chambers were tested at different airflow velocities. The finite element method (FEM) approach was used to implement the numerical simulations. The CLIB temperature, heat transfer coefficient (HTC), melting PCM content, and the output temperature (TOU) of the cooling system were studied at different airflow velocities and PCM volume fractions at different times for different PCM shapes. It was found that a rise in the airflow velocity decreased the average CLIB temperature (TAVE-B) and TOU and increased the HTC of the PCM chamber. The CLIB within a triangular chamber was observed to have the lowest temperature and largest HTC; on the other hand, the lozenge chamber had the lowest heat transfer. The triangular chamber led to 63% higher heat transfer compared to the lozenge chamber. The addition of graphene NPs at a volume fraction of 4% to the PCM improved the HTC by 65% at 5000 s.