Ultrathin Self-Cross-Linked Alkaline Polymer Electrolyte Membrane for APEFC Applications

Ultrathin alkaline polymer electrolyte (APE) membranes have become a hot research topic for high-performance alkaline polymer electrolyte fuel cells (APEFCs). To our knowledge, freestanding ultrathin membranes with thicknesses of or below 10 μm have never been reported for successful applications in APEFCs. The obstacle comes from the poor mechanical strength of the ultrathin membrane during the fuel cell assembly. Herein we report an ultrathin 10 μm membrane made of cross-linked quaternary ammonia poly(N-methylpiperidine-co-p-terphenyl), denoted cQAPPT. This ultrathin cQAPPT membrane is robust enough for fuel cell assembly and demonstrates a high H2/O2 peak power density of 1.85 W/cm2 at 80 °C.