SOLID POLYMER ELECTROLYTE MEMBRANE AND MEMBRANE ELECTRODE ASSEMBLY FOR SOLID POLYMER FUEL CELL

摘要

Disclosed is a membrane electrode assembly for solid polymer fuel cells, which enables to stably attain high power generation performance for a long time in a high temperature low humidity environment. Also disclosed is a solid polymer electrolyte membrane which enables to obtain such a membrane electrode assembly. Specifically disclosed is a solid polymer electrolyte membrane containing a proton conductive polymer, which is characterized in that the proton conductive polymer is a fluorine-containing polymer having a repeating unit containing a group represented by the following formula (a). [chemical formula 1] (a) The solid polymerelectrolyte membrane has a low moisture content of less than 150% by mass and a high electrical conductivity of not less than 0.07 S/cm in an atmosphere maintained at a relative humidity of 40% and at a temperature of 80°C.