Advanced battery thermal management systems: Technologies, integration challenges, and future trends

With the rapid development of electric vehicles and stationary energy storage systems, the thermal safety and performance reliability of lithium-ion batteries have become critical concerns. Battery thermal management systems (BTMS) play a pivotal role in regulating temperature, enhancing operational stability, and mitigating thermal runaway risks. This review provides a comprehensive overview of recent advances in BTMS technologies, systematically categorized into passive, active, and hybrid approaches. Passive strategies, such as heat pipes and phase change materials, offer energy-free operation and structural simplicity but are limited by low thermal conductivity and slow response under dynamic loads. Active cooling methods, including air, liquid, and thermoelectric cooling, deliver controllable and efficient heat removal, though they often involve increased complexity and energy consumption. Hybrid systems integrate multiple mechanisms to achieve synergistic benefits, significantly improving temperature uniformity, transient response, and safety redundancy. Furthermore, this review compares key performance metrics across different BTMS architectures and outlines current challenges in heat transfer efficiency, system integration, and cost-effectiveness. Finally, emerging trends such as data-driven thermal control, multifunctional material integration, and structural co-design are discussed, offering insights into the future direction of intelligent and adaptive thermal management for next-generation battery systems.