Fuel cell stack having foil interconnects and laminated spacers

Abstract

Interconnects and perimeter spacers for a fuel cell stack are provided as flexible elements which can conform to non-planarities in a stack's electrolyte elements and thereby avoid inducing torsional stresses in the electrolyte elements. The interconnects are foil elements about 0.005 inches thick, formed of a superalloy such as Hastelloy, Haynes 230, or a stainless steel. The perimeter spacers comprise a plurality of laminate thin spacer elements, each thin spacer element being a laminate of superalloy and a “soft” material such as copper, nickel, or mica. The spacer elements can slide past one another; thus the perimeter spacers can be physically thick, to form the gas flow spaces within the stack, while also being torsionally flexible.

1 . A perimeter spacer for use in a fuel cell stack, comprising between two and ten laminate spacer elements positioned adjacent to one another, at least one of said spacer elements being formed of a superalloy and a soft material, wherein said soft material is selected from the group consisting of copper and dielectric materials and wherein at least one of the outermost of the laminate spacer elements is formed of mica for sealing and insulating disposition against an electrolyte element in said fuel cell stack.  
     
     
         2 . A perimeter spacer in accordance with  claim 1  wherein said dielectric material is mica.  
     
     
         3 . A perimeter spacer in accordance with  claim 1  configured for spacing an electrolyte element from an interconnect element, wherein said perimeter spacer includes between two and ten laminate spacer elements.  
     
     
         4 . A perimeter spacer in accordance with  claim 2  wherein at least one of the outermost of the laminate spacer elements is formed of mica for sealing and insulating disposition against an electrolyte element in said fuel cell stack.