| abstract |
An excellent polymer electrolyte composition has excellent chemical stability of being resistant to strong oxidizing atmosphere during operation of fuel cell, and achieves excellent proton conductivity under low-humidification conditions, excellent mechanical strength and physical durability. A polymer electrolyte membrane, a membrane electrode assembly, and a polymer electrolyte fuel cell each use the same. The polymer electrolyte composition contains an ionic group-containing polymer (A), a phosphorus-containing additive (B), and a nitrogen-containing aromatic additive (C), the phosphorus-containing additive (B) and the nitrogen-containing aromatic additive (C) being a compound represented by specific structural formulae. |