Optimizing cooling efficiency in Li-ion battery packs: A numerical study on the influence of inter-cell gaps and airflow dynamics

• A 39 % to 51 % improvement in heat transfer is observed as the spacing increases. • Downstream batteries cool less effectively as coolant temperature rises along the flow path. • Average Nusselt number increased by 51.7 %, enhancing convective heat transfer . • Peak battery temperature reduced from 329 K to 301 K, improving cooling efficiency. • Maximum temperature difference decreased by 49.23 °C, ensuring better thermal uniformity. Computational investigations are carried to study the influence of movement of airflow by changing the Reynolds number to enhance the Nusselt number by reducing the li ion battery temperature by modifying the position of battery spacing. In the present study, different spacing patterns are designed to effectively absorb the heat dissipated by the batteries by considering air as the working fluid. It has been noted that as the Re number increases convective heat transfer also increased for all the fluid flow patterns. It is also observed that heat transfer characteristics also enhanced effectively with an increase in the gaps between the batteries. The heat content of the single battery decreases rapidly with higher Re number this is due to the movement of the cold air drastically. The study found that an optimal spacing of 4 mm combined with a higher Reynolds number of 10,000 led to a 51.70 % increase in the average Nusselt number, improving heat dissipation significantly. Additionally, the maximum temperature difference reduced by 49.23 °C, resulting in improved electrical performance and an extended lifespan of the batteries. It is concluded from the present study that with maximum Re number and higher spacing pattern has significant impact on the heat transfer properties of Li-ion batteries in reducing the temperature resulting in improved electrical performance and an extended lifespan of the batteries.