A recent overview of proton exchange membrane fuel cells: Fundamentals, applications, and advances

The research on proton exchange membrane fuel cells (PEMFCs) has significantly escalated due to their exceptional efficiency and eco-friendliness, but there is still much ground to cover. These cells find applications in various sectors such as transportation, portable power, stationary power, aerospace, and underwater. The current focus of research is on improving the performance and reducing the cost of PEMFC components, including catalyst layers, proton exchange membranes, bipolar plates, and diffusion layers. This review provides a critical discussion on the fundamentals of PEMFC, recent and future applications, recent advances in fuel cell component materials and operating conditions, mathematical models used to simulate PEMFCs, challenges faced for PEMFCs applications, and future direction in this field. It starts with a thorough understanding of the process and then evaluates different current and potential applications, highlighting their advantages and disadvantages. The paper also explores recent advances in platinum-based and platinum-free catalysts, Nafion and non-Nafion proton exchange membranes, metallic and non-metallic bipolar plates, and different gas diffuser layers. The mathematical models concerning the PEMFCs are also critically discussed, including lumped and more complex multi-phase multi-dimensional models. Finally, the paper discusses the current status, challenges, and future prospects of PEMFCs. It is evident that despite the need for further research to reduce capital costs and provide more hydrogen infrastructure, PEMFCs hold immense potential for practical applications and continue to be an area of active investigation. Further enhancement in the sustainability and efficiency of PEMFC components is still needed. Also, more focus could be given to H2/air to drive PEMFCs instead of H2/O2 due to the use of air in real applications. Unlike the special PEMFC-related topics reviewed in the literature, this review provides a comprehensive source of updated knowledge for PEMFC researchers, designers, and developers.