CFD analysis of directional airflow and internal baffles for improving thermal uniformity in a 4 × 6 li-ion battery module

Effective thermal management for lithium-ion batteries is a key factor in preventing overheating, maintaining even heat distribution, and extending battery life. Air cooling systems are considered a simple, low-cost, and easy-to-implement solution. However, poor heat transfer efficiency and uneven airflow remain major challenges. This study investigates the impact of airflow direction and internal partitions on the thermal performance of a 4 × 6-cell lithium-ion battery module using Computational Fluid Dynamics (CFD) simulations with ANSYS Fluent software. Five cooling configurations were investigated. The results showed that the novel combination of counter-flow air with internal partitions provided the most optimal cooling performance. This synergy significantly enhanced thermal uniformity and helped maintain safer operating temperatures. Specifically, the maximum temperature T max decreased from 346.852 K to 314.768 K, and the temperature difference between cells ΔT max decreased sharply from 39.7 K to only 2.9 K. The partition enhanced convection and effectively prevented airflow from short-circuiting. Nevertheless, this design also increased pressure loss and fan power consumption by approximately 10%-12% compared to the base configuration. Simulation results demonstrated the superior effectiveness of the combined counterflow and baffle design in air cooling solutions, while providing a technical basis for optimizing a low-cost, high-efficiency, and easily deployable Battery Thermal Management System (BTMS) in practice.