Thermal Management Systems for Electric Vehicles: Nano-Enhanced Materials, Smart Thermal Control, and Thermal Runaway Mitigation

With the increasing use of electric vehicles (EVs), the need for efficient Battery Thermal Management System (BTMS) is also increasing to maintain the safety, thermal stability, charging efficiency and extended operational life of the battery. Lithium-ion batteries are highly sensitive to temperature changes, high power operation and fast charging will generate a lot of heat that can speed up battery degradation, reduce energy efficiency and increase the risk of thermal runaway. Thus, better thermal management technologies are required for reliable operation of next generation EV battery systems. This paper presents a comprehensive review of the recent progresses in battery thermal management technology, with special focus on hybrid cooling systems, nano structured thermal materials and thermal runaway mitigation strategies. In this paper a comprehensive review of the conventional cooling techniques, such as air and liquid cooling, and the developing technologies, such as nanoenhanced phase change materials (PCM), metal-foam-assisted thermal structures, heat pipe cooling, immersion cooling, and hybrid cooling systems, is presented. Recent advances in thermal monitoring systems, battery diagnostics, and improved temperature control technologies are also presented. Furthermore, the paper highlights the importance of thermal barrier materials, self-healing thermal composites, and environmentally sustainable dielectric fluids for enhancing battery safety and thermal stability . A comparative assessment of various cooling solutions is provided in aspects of cooling effectiveness, temperature uniformity, system complexity, energy consumption, thermal runaway protection and practical implementation. This paper identifies major research challenges related to the long-term durability of nano-enhanced PCM materials, large-scale implementation of immersion cooling systems, and thermal management requirements of solid-state batteries. The review concludes that hybrid cooling systems incorporating nano-enhanced PCM materials, immersion cooling technologies, heat pipes and advanced thermal monitoring techniques have enormous potential to improve the safety, efficiency and performance of future electric vehicle battery systems. Future work should address sustainable thermal materials, compact cooling structures and integrated thermal-energy management strategies for next generation electric transportation.