FUEL CELL AND ELECTRODE POWDER FOR CONSTITUTING CATALYST LAYER OF THE FUEL CELL

摘要

Property values of a catalyst layer, which correlate with the performance of a fuel cell, are specified, and a catalyst layer and a fuel cell satisfying the property value requirement are provided. Specifically, the fuel cell comprises a membrane electrode assembly comprising a catalyst layer (13) provided on both sides of an electrolyte membrane (10). The catalyst layer (13) is formed of an electrode powder having a water vapor adsorption in the range of 52 to 70 cm3(STP)/g at a water vapor partial pressure of 0.6 determined from an adsorption isotherm of water. The fuel cell comprising the catalyst layer using the electrode powder having a water vapor adsorption in this water vapor adsorption range has such an output performance that the current density is not less than 0.6 A/cm2 at 0.6 V under low humidified and high humidified conditions.