To boost the performance of the air-cooling battery thermal management system, this study designed a novel vortex adjustment structure for the conventional air-cooling battery pack used in electric vehicles. T-shape vortex generating columns were proposed to be added between the battery cells in the battery pack. This structure could effectively change the aerodynamic patterns and thermodynamic properties of the battery pack, including turbulent eddy frequency, turbulent kinetic energy, and average Reynolds number, etc. The modified aerodynamic patterns and thermodynamic properties increased the heat transfer coefficient with little increase in energy consumption and almost no additional cost. Different designs were also evaluated and optimized under different working conditions. The results showed that the cooling performance of the Design 1 improved at both low and high air flow rates. At a small flow rate of 11.88 L/s, the Tmax and ΔT of Design 1 are 0.85 K and 0.49 K lower than the conventional design with an increase in pressure drop of 0.78 Pa. At a relative high flow rate of 47.52 L/s, the Tmax and ΔT of the Design 1 are also 0.46 K and 0.13 K lower than the conventional design with a slight increase in pressure drop of 17.88 Pa. These results demonstrated that the proposed vortex generating design can improve the cooling performance of the battery pack, which provides a guideline for the design and optimization of the high-performance air-cooling battery thermal management systems in electric vehicles.