Design of header flange to evenly distribute contact pressure across seals

A system comprising:

• a first plate including:
• a bead having a bead-side and a bead-corner;
• and
• a flange edge defining a first aperture through the first plate;
• wherein the flange edge includes a first edge-portion proximate the bead-side and a second edge-portion proximate the bead-corner;
• wherein the bead-side and the first edge-portion define a first edge-distance therebetween;
• wherein the bead-corner and the second edge-portion define a second edge-distance therebetween;
• and
• further wherein the second edge-distance is greater than the first edge-distance;
• a second plate abutting the first plate, the second plate defining a second aperture therethrough that is aligned with the first aperture;
• and
• a compressive member configured to exert a compressive force on the first plate and the second plate, wherein the compressive force is configured to seal the first plate and the second plate along the bead.

A fuel-cell stack comprising:

• a first plate including:
• a first working face defining a plurality of first reactant channels;
• a bead disposed on the first working face, the bead having a bead-side and a bead-corner;
• and
• a first flange edge defining a first aperture through the first plate, the first flange edge including a first edge-portion proximate the bead-side and a second edge-portion proximate the bead-corner;
• wherein the first edge-portion and the bead-side define a first edge-distance therebetween;
• wherein the second edge-portion and the bead-corner define a second edge-distance therebetween;
• and
• further wherein the second edge-distance is greater than the first edge-distance;
• a second plate including:
• a second working face defining a plurality of second reactant channels;
• and
• a second flange edge defining a second aperture through the second plate, the second aperture being aligned with the first aperture;
• a unified electrode assembly disposed between the first plate and the second plate, the unified electrode assembly including a first side contacting the plurality of first reactant channels and a second side contacting the plurality of second reactant channels;
• and
• a compressive member configured to exert a compressive force on the first plate, the second plate, and the unified electrode assembly;
• wherein the compressive force is configured to apply a contact pressure to the bead to provide a substantially fluid-tight seal between the bead and the second plate or the unified electrode assembly.