Review on Thermal Management System of Electric Vehicles
Abstract
The rapid growth of electric vehicles (EVs) has transformed the transportation sector by reducing dependence on fossil fuels and minimizing greenhouse gas emissions. However, the reliability, safety, and efficiency of EVs strongly depend on effective thermal management. Electric vehicle subsystems such as lithium-ion batteries, electric motors, power electronic converters, and charging systems generate substantial heat during operation. Excessive temperature rise can lead to reduced efficiency, accelerated degradation, lower driving range, and severe safety concerns including thermal runaway. Therefore, a robust Thermal Management System (TMS) is essential to maintain optimal operating conditions. This paper presents a detailed review of thermal management systems used in electric vehicles with emphasis on battery thermal regulation, cooling technologies, and intelligent thermal control strategies. Various cooling approaches including air cooling, liquid cooling, refrigerant cooling, phase change materials (PCM), heat pipes, and nanofluid-based cooling are critically analyzed. The paper also discusses thermal modeling techniques, computational fluid dynamics (CFD) simulations, and experimental investigations carried out for EV battery packs and associated subsystems. Comparative analysis shows that liquid cooling systems provide superior heat dissipation, whereas hybrid systems integrating PCM and nanofluids offer improved thermal stability and energy efficiency. Additionally, the study highlights major challenges such as cost, system complexity, packaging constraints, coolant leakage, and environmental considerations. Emerging technologies including artificial intelligence-based predictive cooling, smart sensors, digital twins, and eco-friendly cooling materials are explored as future directions. The paper concludes that advanced and integrated thermal management systems are fundamental for improving EV safety, extending battery lifespan, enhancing vehicle performance, and supporting sustainable transportation