CFD-Driven Design of an Air-Cooling System for Lithium-Ion Battery Packs in a Formula Student Car

In the high-performance environment of Formula Student Car racing, effective battery thermal management is crucial for safety, reliability, and performance. This work presents the design and validation of a lightweight, air-based Battery Cooling System (BCS) developed for a Formula Student vehicle. The system addresses the significant thermal loads generated by 528 Molicel P45B lithium-ion cells, arranged in a constrained U-shaped module layout. Using Computational Fluid Dynamics (CFD), the airflow geometry was optimized to deliver uniform cooling across all modules while minimizing aerodynamic drag. Simulations evaluated the system’s performance under various ambient temperatures (25 °C and 30 °C) and airflow velocities (from 16 m/s to 18 m/s), identifying the impact of duct geometry, internal air guides, and airflow distribution on thermal regulation. Results showed that, at nominal ambient temperature (25 °C), all monitored cells stayed below the 60 °C threshold required by FS regulations. At elevated ambient conditions (30 °C), regions above 60 °C appeared within the pack, revealing non-uniform cooling and reduced safety margin. These findings suggest that, while the system complies with current rules, additional design refinements are needed to enhance robustness under harsher conditions. Additionally, these results are specific to a Formula Student application under competition constraints and are not intended to be generalized to production EVs.