Proton exchange membrane fuel cell external manifold seal

A method of sealing a perimeter surface of a reactant gas manifold to end plates and fuel cell component elements of a proton exchange membrane fuel cell, comprising:

• (a) first, applying at least one type of silicone rubber to the regions of said fuel cell elements that are to be sealed to said manifold, to provide bridges having smooth, flat surfaces to which said manifold is to be sealed;
• (b) then causing said silicone rubber to cure;
• (c) thereafter providing an elastomer, having a low compression set and a low compression modulus;
• and
• (d) installing said manifold on said fuel cell with its entire contact perimeter surface in contact with said elastomer, said elastomer being between (1) said manifold and (2) said bridges and said end plates.

A method of sealing a perimeter surface of a reactant gas manifold to end plates and fuel cell component elements of a proton exchange membrane fuel cell, comprising:

• (a) first, applying at least one type of silicone rubber (1) to the regions of said fuel cell elements that are to be sealed to said manifold and (2) to said end plates between said regions, to provide a single seal surface which is relatively smooth and flat to which said manifold is to be sealed;
• (b) then causing said silicone rubber to cure;
• (c) thereafter providing an elastomer, having a low compression set and a low compression modulus;
• and
• (d) installing said manifold on said fuel cell with its entire contact perimeter surface in contact with said elastomer, said elastomer being between said manifold and said seal surface.