Proton exchange membrane fuel cells (PEMFCs) offer a promising solution for power generation, boasting higher efficiency than traditional coal combustion engines and a more environmentally friendly design. Proton exchange membranes play a crucial role in determining the overall performance of PEMFCs. Significant efforts have been dedicated to this area, resulting in the development of innovative material systems. Membranes employing phosphoric acid (PA) as the proton conductor currently dominate the field of high-temperature proton exchange membranes operating in the temperature range of 100~200 °C. This paper aims to provide a concise overview of high-temperature proton exchange membranes (HT-PEMs) to aid researchers in obtaining essential information efficiently. The proton conduction and fundamental principles, recent research efforts and limitations, as well as the challenges and promising directions for future advancements of PA-dependent HT-PEMs are summarized.



