Abstract In this study, a total of three simulations were carried out to investigate the performance of air-cooling based on a 1S18P lithium battery pack using 21700 battery cells, a benchmark model was built as the first simulation to prove the feasibility of battery pack set up. After that, two comparison models with different layouts which are based on the benchmark model were set up and simulated to compare the cooling effect of two different air-cooling configurations, ANSYS Fluent is the main software to carry out the simulation. The Simulation results will be compared by charts to search for a better layout.