Fuel cell sealing structure

A fuel cell sealing structure comprising:

• a power generating body having a membrane electrode assembly provided with electrode layers on both surfaces of an electrolyte membrane;
• and
• first and second separators arranged on both sides in a thickness direction of said power generating body,
• wherein a first sealing protrusion is provided on a first surface of said first separator, said first sealing protrusion being brought into close contact with an outer peripheral portion of said power generating body,
• a second sealing protrusion is provided on said first surface of said first separator, said second sealing protrusion being brought into close contact with said second separator on an outer peripheral side of said first sealing protrusion,
• a short circuit prevention rib is provided on said first surface of said first separator, said short circuit prevention rib, said first sealing protrusion, and said second sealing protrusion all protruding in a first direction away from the first surface of the first separator,
• a third sealing protrusion is provided on a second surface of said first separator, the second surface being opposite the first surface, said third sealing protrusion protruding in a second direction opposite to the first direction, and
• the first sealing protrusion, the second sealing protrusion, the short circuit prevention rib and the third sealing protrusion are integral with one another and formed of an electrically insulating rubber-like elastic material,
• wherein the short circuit prevention rib includes a planar membrane entirely covering a recessed portion of the first separator recessed in the first direction and integrated with the third protrusion.

A fuel cell sealing structure comprising:

• a power generating body including:
• an electrolyte membrane;
• and
• electrode layers on opposite surfaces of the electrolyte membrane;
• first and second separators on opposite sides of said power generating body;
• and
• a gasket integrated with the first separator, the gasket including:
• a first sealing protrusion provided on a first surface of said first separator and protruding in a first direction;
• a second sealing protrusion provided on said first surface of said first separator and protruding in said first direction;
• a short circuit prevention rib provided on said first surface of said first separator and protruding in said first direction;
• and
• a third sealing protrusion provided on a second surface of said first separator and protruding in a second direction opposite to the first direction, the second surface being opposite the first surface,
• wherein the first separator includes:
• a first concavity recessed in the second direction, the first sealing protrusion, the second sealing protrusion and the short circuit prevention rib all protruding from within the first concavity;
• a second concavity recessed in the first direction, the third sealing protrusion protruding from within the second concavity;
• and
• a step portion extending between the first and second concavities, the step portion including at least one communication hole formed therethrough, and
• wherein the first sealing protrusion, the second sealing protrusion, the short circuit prevention rib and the third sealing protrusion are monolithically continuous with one another via said at least one communication hole and formed of an electrically insulating rubber-like elastic material.

A fuel cell sealing structure comprising:

• a power generating body having a membrane electrode assembly provided with electrode layers on both surfaces of an electrolyte membrane;
• and
• first and second separators arranged on both sides in a thickness direction of said power generating body,
• wherein a first sealing protrusion is provided on a first surface of said first separator, said first sealing protrusion being brought into close contact with an outer peripheral portion of said power generating body,
• a second sealing protrusion is provided on said first surface of said first separator, said second sealing protrusion being brought into close contact with said second separator on an outer peripheral side of said first sealing protrusion,
• a short circuit prevention rib is provided on said first surface of said first separator, said short circuit prevention rib, said first sealing protrusion, and said second sealing protrusion all protruding in a first direction away from the first surface of the first separator,
• a third sealing protrusion is provided on a second surface of said first separator, the second surface being opposite the first surface, said third sealing protrusion protruding in a second direction opposite to the first direction, and
• the first sealing protrusion, the second sealing protrusion, the short circuit prevention rib and the third sealing protrusion are integral with one another and formed of an electrically insulating rubber-like elastic material,
• wherein the third sealing protrusion protrudes from a position between the first sealing protrusion and the second sealing protrusion.