Patent ID: 7803494

Claim:
A stress reducing mounting in a solid electrolyte fuel cell for an electrolyte sheet assembly of a type less than 200 microns in thickness that includes a flexible sheet of ceramic material whose periphery forms a peripheral portion of the electrolyte sheet, comprising: a support assembly having an inner edge portion that supports said peripheral portion of said electrolyte sheet; a seal that secures an edge of said peripheral portion of said electrolyte sheet to said support assembly, and a stress reducer located on one or the other of said peripheral portion of said electrolyte sheet and said support assembly inner edge portion that reduces tensile stress in the flexible ceramic sheet forming said peripheral portion caused by a bending of said peripheral portion of said electrolyte sheet adjacent to said inner edge portion, wherein said stress reducer is at least one of a convex curved surface on said inner edge portion of said support assembly that makes area contact with said peripheral portion when said peripheral portion bends over said inner edge portion, and a stiffening structure on said sheet peripheral portion that renders said ceramic sheet material forming said peripheral portion more resistant to bending and wherein said electrolyte sheet assembly includes a supporting sheet of ceramic material that is thinner than an electrode portion of said electrolyte sheet, and that forms said peripheral portion, and said stiffening structure includes a thickening of said ceramic material forming said peripheral portion such that the thickness of said periphery of said ceramic sheet approaches or equals the thickness of an electrode portion of said electrolyte sheet assembly.