Patent ID: 7977003

Claim:
A fuel cell comprising a membrane electrode assembly and first and second separators sandwiching said membrane electrode assembly, said membrane electrode assembly including a first electrode and a second electrode, and an electrolyte membrane interposed between said first electrode and said second electrode, the surface area of said second electrode being larger than the surface area of said first electrode, wherein said first separator has a first seal member provided outside said first electrode such that said first seal member contacts said membrane electrode assembly; said second separator has a second seal member provided outside said membrane electrode assembly such that said second seal member contacts said first separator; first ribs are formed integrally with said first seal member, and second ribs are formed integrally with said second seal member such that said first ribs and said second ribs are arranged alternately along a surface of the separator across the length of the separator in a direction in which the seal member extends such that a lengthwise space exists between each first rib and each second rib; the first ribs extend outwardly from the first seal member toward the second seal member, and the second ribs extend inwardly from the second seal member that is different than the first seal member toward the first seal member; and the first ribs are provided on the first separator and contact the membrane electrode assembly, and the second ribs are provided on the second separator and contact the first separator.