Design and simulation of an air cooling system for lithium-ion batteries packs

Abstract

With the widespread application of electric vehicles and energy storage devices, the thermal management of lithium-ion batteries has gradually become a key factor limiting their performance and safety. This paper focuses on a battery pack composed of 18650 cylindrical lithium-ion cells, establishing a three-dimensional geometric model and a thermo-fluid coupled mathematical model. Finite element numerical simulations are conducted using the COMSOL Multiphysics platform to systematically analyze the effects of different structural parameters on the temperature and flow field distributions under air cooling conditions. During the simulation, the influence of factors such as inlet air velocity, the relative position of the inlet and outlet, and the size of ventilation holes on the heat dissipation performance is investigated. The results show that appropriately increasing the inlet velocity, enlarging the ventilation area, and optimizing the layout of the inlet and outlet can help reduce the maximum surface temperature and temperature difference of the battery, thereby improving temperature uniformity. This study provides theoretical guidance and simulation support for the design optimization of thermal management structures in lithium-ion battery packs.