Electrochemical cells having current-carrying structures underlying electrochemical reaction layers

Abstract

An electrochemical cell structure has an electrical current-carrying structure which, at least in part, underlies an electrochemical reaction layer. The cell comprises an ion exchange membrane with a catalyst layer on each side thereof. The ion exchange membrane may comprise, for example, a proton exchange membrane. Some embodiments of the invention provide electrochemical cell layers which have a plurality of individual unit cells formed on a sheet of ion exchange membrane material.

1 . (canceled) 
     
     
         2 . An electrochemical cell layer comprising:
 an ion exchange membrane including an ion-conducting material;   a plurality of electrically-isolated electrochemical cells, wherein each electrochemical cell includes a first and second electrochemical reaction layers located on opposite sides of the ion exchange membrane and a substrate respectively, and wherein each electrochemical reaction layer includes an inner surface at least partially in contact with the ion exchange membrane and an outer surface opposite the inner surface;   one or more first current-carrying structures and one or more second current-carrying structures located on opposite sides of the ion exchange membrane, wherein the first current-carrying structures are located on a first side of the substrate and the second current-carrying structures are located on a second side of the substrate being opposite to the first side of the substrate, each current-carrying structure having electrically conducting portions in contact with one of the electrochemical reaction layers, wherein the electrically conducting portion of at least one of the current-carrying structures is located on the inner surface of the associated electrochemical reaction layer; and   an electrically conducting pathway embedded in the substrate and electrically connecting one of the first current-carrying structures of a first one of electrochemical cells to one of the second current-carrying structures of an adjacent one of the electrochemical cells;   wherein the substrate is constructed from an electrically nonconductive material and provides electrical insulation between the electrically conducting pathway and the ion conducting material.   
     
     
         3 . The electrochemical cell layer of  claim 2 , further including a plurality of electrically insulating regions between adjacent electrochemical reaction regions. 
     
     
         4 . The electrochemical cell layer of  claim 3 , wherein the electrically insulating regions include an air gap. 
     
     
         5 . The electrochemical cell layer of  claim 4 , wherein the air gap exposes at least a portion of the substrate. 
     
     
         6 . The electrochemical cell layer of  claim 4 , wherein the air gap exposes at least a portion of at least one of the current-carrying structures. 
     
     
         7 . The electrochemical cell layer of  claim 2 , wherein the electrochemical reaction layers are disposed on the substrate. 
     
     
         8 . The electrochemical cell layer of  claim 2 , wherein the electrochemical reaction layers include a catalyst material. 
     
     
         9 . The electrochemical cell layer of  claim 2 , wherein the plurality of electrically-isolated electrochemical cells is an array of fuel cells. 
     
     
         10 . The electrochemical cell layer of  claim 9 , wherein the fuel cells are proton exchange membrane fuel cells. 
     
     
         11 . The electrochemical cell layer of  claim 2 , wherein the electrochemical cell layer is substantially planar. 
     
     
         12 . The electrochemical cell layer of  claim 2 , further including a gas diffusion layer positioned on the electrochemical reaction layers. 
     
     
         13 . The electrochemical cell layer of  claim 2 , wherein the current-carrying structures direct a current orthogonally to the electrochemical cell layer. 
     
     
         14 . The electrochemical cell layer of  claim 2 , wherein the ion exchange membrane contacts at least two substrate components. 
     
     
         15 . The electrochemical cell layer of  claim 2 , wherein at least one of the current-carrying structures is in contact with the ion exchange membrane. 
     
     
         16 . A fuel cell comprising:
 a substrate including an opening;   an ion-conducting material disposed in the opening to form an ion exchange membrane;   two electrochemical reaction layers located on opposite sides of the ion exchange membrane, each electrochemical reaction layer having an inner surface in contact with the ion exchange membrane and an outer surface opposite the inner surface;   two current-carrying structures, each current-carrying structure in electrical contact with an associated one of the electrochemical reaction layers and each current-carrying structure located inwardly from the inner surface of the associated electrochemical reaction layer, and   wherein the fuel cell is interconnectable with an adjacent fuel cell by way of electrically conducting paths embedded in the substrate, wherein the conducting paths are connected to one of the current carrying structures by way of electrically conducting vias formed in the substrate, and wherein the substrate is constructed from an electrically nonconductive material.   
     
     
         17 . The fuel cell of  claim 16 , further including a plurality of electrically insulating regions adjacent each of the electrochemical reaction regions, wherein the electrically insulating regions include an air gap. 
     
     
         18 . The fuel cell of  claim 17 , wherein the air gap exposes at least a portion of the substrate. 
     
     
         19 . The fuel cell of  claim 17 , wherein the air gap exposes at least a portion of at least one of the current-carrying structures. 
     
     
         20 . The fuel cell of  claim 16 , wherein the electrochemical reaction layers are disposed on the substrate. 
     
     
         21 . The fuel cell of  claim 16 , wherein the electrochemical reaction layers include a catalyst material.