Recent advances and challenges in electric vehicle Li-ion battery cooling systems

The rapid growth of electric vehicles has intensified the challenge of maintaining lithium-ion batteries within safe and optimal temperature limits under high power and fast-charging conditions. Although numerous battery thermal management systems (BTMS) have been proposed, no clear and quantitative comparison of their performance, energy efficiency, cost, and scalability. The purpose of this review study is to critically evaluate state-of-the-art BTMS technologies and identify their practical trade-offs and future development pathways. Air, liquid, phase change material (PCM), refrigerant-based, thermoelectric, and hybrid cooling systems are comparatively analyzed using key performance indicators such as maximum cell temperature, temperature nonuniformity, cooling time, auxiliary energy consumption, and economic considerations. The review reveals that liquid and refrigerant-based systems provide superior heat removal for high-power and fast-charging applications, while PCM-based and hybrid configurations significantly enhance temperature uniformity and safety with reduced energy penalties. Hybrid systems emerge as the most promising solutions, offering balanced thermal performance, efficiency, and thermal runaway mitigation, although at higher complexity and cost. The review concludes by outlining future trends, highlighting AI-driven adaptive control, advanced two-phase cooling, and sustainable thermal materials as critical enablers for next-generation automotive BTMS.