Performance failure mechanisms and mitigation strategies of high-temperature proton exchange membrane fuel cells

As one type of promising electrochemical technologies, high temperature proton exchange membrane fuel cells (HT-PEMFCs) have been widely recognized as the next-generation fuel cell technology for clean energy conversion due to their superiorities of fast electrochemical kinetics, simplified water management, good tolerance to feeding gas contaminants, low emission and high efficiency of energy conversion. However, performance failure during long-term operation still largely hinders their practical application. Accordingly, the explorations of advanced materials and structures, degradation mechanisms and mitigation strategies are attracting intensive attentions for promoting the progress of this technology. In addressing the timely update on the emerging progress regrading long-term durability of HT-PEMFCs, a comprehensive review summarizing the most recent developments of performance failure mechanisms and mitigation strategies for critical components of HT-PEMFCs is presented here. In this paper, the fundamentals involving basic reactions, main components, and development history are first summarized for fundamental understanding; then, the failure analysis and the corresponding mitigation strategies for critical components involving proton exchange membrane, catalytic layer, gas diffusion layer, bipolar plate, and thermal/water management systems are mainly emphasized. Furthermore, the technical challenges are analyzed and the further research directions are also proposed for overcoming the challenges toward practical application of HT-PEMFCs.