| abstract |
A polymer electrolyte composition having excellent chemical stability capable of withstanding a strong oxidizing atmosphere during operation of a fuel cell and having excellent practical proton conductivity, excellent mechanical strength and physical durability under low humidification conditions, and polymer electrolyte membrane , A membrane electrode assembly, and a polymer electrolyte fuel cell. A polymer electrolyte composition comprising an ionic group-containing polymer (A), a phosphorus-containing additive (B), and a nitrogen-containing aromatic ring additive (C), wherein the phosphorus-containing additive (B) Is a polymer electrolyte composition which is a compound represented by a specific structural formula. |