Binderless electrodes for high-temperature polymer electrolyte membrane fuel cells

A new electrode concept was proved with no polymeric binder in the catalyst layer for acid-doped polybenzimidazole (PBI) membrane fuel cells. It shows that a stable interface between the membrane and the catalyst layer can be retained when a proton conducting acid phase is established. The absence of the polymer in the catalytic layer turned out to be beneficial for the PBI cell performance particularly under high load operation. The influence on performance of the Pt loading of the cathode was studied in a range from 0.11 to 2.04 mgp sub(Pt) cm super(-2) showing saturation of the maximum performance for Pt loadings higher than 0.5 mg sub(Pt) cm super(-2). For fuel cell operation on H sub(2) and air supplied under ambient pressure, a peak power density as high as 471 mW cm super(-2) was measured. The tolerance to carbon monoxide (CO) was also studied with Pt loadings of the anode ranging from 0.24 to 1.82 mgp sub(Pt) cm super(-2). Lifetime test for a MEA loaded with 0.96 mg sub(Pt) cm super(-2) on both electrodes revealed no voltage decay during 900 h of uninterrupted operation at 200 mA cm super(-2) and 160 [degrees]C.