Gasketed subassembly for use in fuel cells including replicated structures

Abstract

The present invention is an electrochemical device subassembly that includes a membrane electrode assembly and a gasket. The membrane electrode assembly includes an electrolyte membrane having a first major surface, a second major surface opposite the first major surface, and a peripheral edge. The gasket is disposed adjacent the first major surface of the electrolyte membrane at the peripheral edge, and has a plurality of replicated structures that extend greater than about 250 micrometers from a surface of the gasket.

1 . A method of making an electrochemical device subassembly, the method comprising:
 fabricating a gasket film comprising an elastomeric layer having replicated structures;   separating the gasket film into at least a first portion and a second portion;   connecting the first portion of the gasket film to a first major surface of an electrolyte membrane at a peripheral edge of the electrolyte membrane; and   connecting the second portion of the gasket film to a second major surface of the electrolyte membrane at the peripheral edge of the electrolyte membrane.   
     
     
         2 . The method of  claim 1 , wherein the gasket film further comprises a base layer secured to the elastomeric layer, the base layer having a lower compressibility than the elastomeric layer. 
     
     
         3 . The method of  claim 1 , wherein the first portion of the gasket film has a first gasket surface and the replicated structures of the first portion extend greater than about 250 micrometers from the first gasket surface, and wherein the second portion of the gasket film has a second gasket surface and the replicated structures of the second portion extend greater than about 250 micrometers from the second gasket surface. 
     
     
         4 . The method of  claim 1 , wherein fabricating the gasket film is selected from the group consisting of extrusion, drop casting, calendering, coating, and combinations thereof. 
     
     
         5 . The method of  claim 1 , further comprising forming the replicated structures in the elastomeric layer. 
     
     
         6 . The method of  claim 5 , wherein forming the replicated structures is selected from the group consisting of compression molding, injection molding, embossing, and combinations thereof. 
     
     
         7 . The method of  claim 1 , wherein the base layer is selected from the group consisting of polyethylene terephthalate, polyethylene naphthalate, polypropylene, polyethylene, polycarbonate, polyimide, and combinations thereof.