Patent ID: 7138201

Claim:
A polymer electrolyte fuel cell, comprising: a seal formed from a liquid thermosetting sealing agent, and a lamination of separators and a membrane electrode assembly tightly sealed with the seal; a gap formed between each separator and the membrane electrode assembly, wherein said seal is formed by applying the liquid thermosetting sealing agent into the gap, thermally curing the liquid thermosetting sealing agent at a temperature in a range of from 100 to 130° C. over a period of from 1 to 5 hours, the liquid thermosetting sealing agent is based on a silicone series elastomer or isobutylene series elastomer, and a viscosity of the liquid thermosetting sealing agent at application is from 1,000 to 9,000 Pa.s, wherein upon curing, the seal has a permanent deformation of 60% or less when thermally aged at 90° C. for 100 hours to retain the gap upon sealing.