REVERSAL TOLERANT MEMBRANE ELECTRODE ASSEMBLY FOR A FUEL CELL

摘要

A membrane electrode assembly (MEA) for a fuel cell which exhibits enhanced reversal tolerance. In particular, a layer of iridium or an iridium compound, preferably metallic iridium or iridium oxide supported on TiO2, is provided on the anode to electrolyze available water and pass the majority of the current during a reversal of the fuel cell, thereby preventing damage to the MEA. The iridium or iridium compound is applied to an anode structure according to a predetermined pattern, with only part of the anode active area containing Ir. The parts of the MEA that do not contain Ir are not expected to suffer degradation from Ir cross-over, so that overall degradation of the cell will be diminished. Having less precious metals will also translate into less cost.

主权项

1. A reversal tolerant anode for a fuel cell which comprises an oxygen evolution reaction catalyst disposed in selected areas of the anode, with only part of the anode structure containing the oxygen evolution reaction catalyst,
wherein the selected areas are provided to the surface of the anode according to a predetermined pattern, wherein the predetermined pattern comprises that the selected areas are larger in size the narrower to the anode outlet they are disposed, and wherein the oxygen evolution reaction catalyst is comprised of metallic iridium or an iridium compound.