A Quaternary Polybenzimidazole Membrane for Intermediate Temperature Polymer Electrolyte Membrane Fuel Cells

摘要

A quaternary ammonium polybenzimidazole (QPBI) membrane was synthesized for applications in intermediate temperature (100-200℃) hydrogen fuel cells. The QPBI membrane was imbibed with phosphoric acid to provide suitable proton conductivity. The proton conductivity of the membrane was 0.051 S·cm~(-1) at 150℃ with the PA acid loading level of 3.5 PRU (amount of H_3PO_4 per repeat unit of polymer QPBI). The QPBI membrane was characterized in terms of composition, structure and morphology by NMR, FTIR, SEM, and EDX. The fuel cell performance with the membrane gave peak power densities of 440 and 240 mW·cm~(-2) using oxygen and air, respectively, at 175℃.