Development of high-performance membrane-electrode assembly in unitized regenerative fuel cells

Abstract

In this work, we investigated the membrane-electrode assembly (MEA) parameters of an oxygen electrode to develop a high-performance unitized regenerative fuel cell (URFC) that can be operated in fuel cell (FC) and water electrolysis (WE) mode. The MEA parameters including gas diffusion layer, ionomer content, oxygen reduction reaction (ORR) type, oxygen evolution reaction (OER) catalyst, and catalyst loading were optimized by calculating the round-trip efficiency of URFC. The performance in FC mode was largely affected by the MEA parameters compared to that of the WE mode performance. The FC mode performance is crucial for the achievement of high URFC performance. The optimized round-trip efficiency was 49% at 500mAcm−2, which is comparable or superior to that reported in literature. This result can be attributed to the highly efficient MEA structure suitable for bifunctional catalysts to participate in both ORR and OER.