Polybenzimidazoles for High Temperature Fuel Cell Applications

Summary: Fuel cells were designed for high temperature operations. Poly[2,2′‐(m‐phenylene)‐5,5′‐bibenzimidazole] (PBI) was synthesized in a solution of P2O5, CH3SO3H, and CF3SO3H. The PBI was dissolved in a mixture of CF3CO2H and H3PO4 and the solution was used for the preparation of Pt catalyst slurry for membrane electrode assembly. The single cell showed a current density of 280 mA · cm−2 at a cell voltage of 0.5 V with feeds of H2 and O2 at 160 °C and without external humidification. magnified image