Battery thermal performance evaluation with regular polygon arrangement under natural convection*

Natural convection, being independent of additional power sources, is currently regarded as the most reliable method for dissipating heat. This study investigates the heat dissipation of Lithium-ion batteries under natural convection using different packaging methods and arrangements through simulation research. The results indicate that non-packaged battery modules demonstrate superior heat dissipation, while conventional packaging methods significantly influence heat dissipation. Moreover, the impact of packaging on heat dissipation varies with battery arrangement. A regular polygon based method is introduced here to represent the centrally symmetric arrangements for batteries. The results showed that the circular arrangement method is more conducive to the heat dissipation of the battery. Finally, the performance of battery modules is evaluated using volumetric effective energy after 500 cycles. The findings reveal that the non-packaged 4x4 array achieves the highest remaining volumetric effective energy at a 0.5C discharge rate, measuring 1.7 J/mm³, compared to 0.84 J/mm³ for the 3x3 array under identical conditions.