Recent Advances in the Development of Unitized Regenerative Fuel cells based on PEM technology

Unitized Regenerative Fuel Cells (URFC) are reversible electrochemical devices which can alternatively operate as a water electrolyser or a H2/O2 (air) fuel cell. Results reported in this communication are related to R&D on bi-functional electrocatalysts and stack development. Pt-Ir mixtures have been used as anodic catalyst for water and hydrogen oxidation. Carbonsupported platinum has been used for hydrogen evolution and oxygen reduction. A two-cell stack with 250 cm active area electrodes has been assembled and successfully tested. Electrochemical performances are close to those obtained with conventional water electrolysers and H2/O2 fuel cells. Typical cell voltages of 1.55 and 0.70 V have been recorded at a current density of 0.2 A.cm, during respectively water electrolysis and H2/O2 fuel cell operation.