Abstract Lithium-ion capacitor (LiC) has emerged as a promising technology for high power applications due to the solution offered by its power density, higher-voltage operation than super-capacitor (SC), and their excellent durability (more than 2 million cycles). However, for this kind of applications, a thermal management system is crucial to ensure thermal stability and a long lifespan. Nonetheless, in order to design a proper thermal management system, dedicated thermal modelling development is an essential task. In this study, a detailed three-dimensional thermal model is developed in COMSOL Multiphysics software at cell and module level. Pertaining to the versatility of the detailed model, an air-cooled thermal management system is designed considering different topologies. Then, different operating and design parameters including inlet air speed, inter-cell spacing, and the airflow direction are studied comprehensively. The simulation results are validated with experimental results showing an acceptable error of less than 2 ° C. It is proved and validated that the side cooling topology with a 5 m/s air velocity and a 5 mm spacing between cells is the optimum design.