A comprehensive review of thermal management strategies in PEM fuel cells: From conventional cooling methods to advanced passive and hybrid solutions for sustainable energy application

Polymer Electrolyte Membrane (PEM) fuel cells have emerged as key technologies in the global shift toward sustainable energy systems, owing to their high efficiency and environmental compatibility. However, effective thermal management-especially under high current densities and cold-start conditions-remains a critical challenge to commercialization and long-term performance. This review systematically evaluates thermal management strategies for PEM fuel cells based on research published over the past decade. Both active and passive cooling methods are examined, with a focus on performance, integration feasibility, and operational limitations. In addition to conventional air and liquid cooling systems, advanced techniques such as metal foam integration, phase change materials (PCMs), nanofluid-based cooling, and hybrid systems are reviewed. Key thermal performance indicators-such as average temperature (Tavg), maximum temperature (Tmax), and the Index of Uniform Temperature (IUT)-are used to compare effectiveness. The results indicate that while air cooling and basic passive systems are suitable for low-power applications, they are insufficient for high-power demands. Liquid cooling improves thermal uniformity and is widely adopted in automotive applications. Meanwhile, hybrid (e.g. serpentine channel + metal foam) and PCM-enhanced systems show promise but face issues such as increased pressure drop, structural complexity, and material compatibility. The review also highlights the lack of standardized evaluation metrics, which hinders consistent benchmarking across studies. By addressing these gaps and synthesizing performance trends, this study provides a comprehensive reference to guide future research and design. Scalable, integrated thermal management solutions-particularly hybrid approaches-are essential to support the durability and commercialization of PEM fuel cell technologies.