Anode support member and bipolar separator for use in a fuel cell assembly and for preventing poisoning of reforming catalyst

Abstract

An anode support for supporting an anode electrode in a fuel cell assembly in which the anode support has a first support member formed of a porous non-wettable material and a second support member abutting and joined with the second member and having a plurality of through openings. Also disclosed is a bipolar separator having an electrolyte barrier over predetermined limited portions of its outer surface so as to prevent or retard electrolyte creeping.

1 . An anode support for supporting an anode electrode in a fuel cell assembly, said anode support comprising: 
 a first support member comprising a porous non-wettable material; and    a second support member comprising a non-wettable metallic member having a plurality of through openings,    wherein said first support member abuts and is joined with said second support member.    
     
     
         2 . An anode support in accordance with  claim 1 , wherein said first support member comprises at least one of Ni, Cu, Ni alloy and Cu alloy.  
     
     
         3 . An anode support in accordance with  claim 2 , wherein said first support member comprises one of a high porosity reticulated foam material and a porous sintered powder bed.  
     
     
         4 . An anode support member in accordance with  claim 3 , wherein said first support member has a porosity of less than 70% and a mean pore size of at least 20 μm.  
     
     
         5 . An anode support in accordance with  claim 4 , wherein a thickness of said first support member is at least 2 mils.  
     
     
         6 . An anode support in accordance with  claim 1 , wherein said second support member comprises one of a wire mesh, an expanded wire mesh, and a perforated plate member.  
     
     
         7 . An anode support in accordance with  claim 6 , wherein said second support member comprises at least one of Ni, Cu, Ni alloy and Cu alloy.  
     
     
         8 . An anode support in accordance with  claim 7 , wherein said second support member has a thickness of at least 5 mils.  
     
     
         9 . An anode support in accordance with  claim 8 , wherein said through openings in said second support member are 20 mils or smaller in diameter and said openings comprise at least 40% of an area of said second support member.  
     
     
         10 . An anode support in accordance with  claim 3 , wherein said second support member comprises one of a wire mesh, an expanded wire mesh, and a perforated plate member, said second support member is formed from at least one of Ni, Cu, Ni alloy and Cu alloy.  
     
     
         11 . An anode support member in accordance with  claim 10 , wherein said first support member is joined with said second support member using a lamination process.  
     
     
         12 . An anode support in accordance with  claim 11 , wherein said first support member forms a first surface of said anode support and said second support member forms a second surface of said anode support, and said first surface is adapted to abut said anode electrode and said second surface is adapted to abut an anode current collector of said fuel cell assembly.  
     
     
         13 . A bipolar separator for use with a fuel cell comprising: 
 a plate member having opposing first and second surfaces compatible with fuel gas and oxidant gas, respectively, said plate member having first and second opposing ends and third and fourth opposing ends;    first, second, third and fourth pocket members, said first and second pocket members being situated adjacent said first and second opposing ends of said plate member and extending outward of said first surface and then facing each other and said third and fourth pocket members being situated adjacent said third and fourth opposing ends of said plate member and extending outward of said second surface and then facing each other;    said bipolar separator having first and second outer surface parts formed by the outer surfaces of said third and fourth pocket members, respectively;    and an electrolyte barrier comprising a non-wettable material situated on a limited portion of the outer surface of said third pocket member and a limited portion of the outer surface of said fourth pocket member.    
     
     
         14 . A bipolar separator in accordance with  claim 13 , wherein: 
 said limited portion of said outer surface of said third pocket member includes a surface portion at the end of said outer surface of said third pocket member closest said plate member; and    said limited portion of said outer surface of said fourth pocket member includes a surface portion at the end of said outer surface of said fourth pocket member closest said plate member.    
     
     
         15 . A bipolar separator in accordance with  claim 14 , wherein said electrolyte barrier comprises one of a weld bead, a foil welded to and a coating applied to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member.  
     
     
         16 . A bipolar separator in accordance with  claim 15 , wherein said electrolyte barrier comprises at least one of Ni, Cu, Ni alloy and Cu alloy.  
     
     
         17 . A bipolar separator in accordance with  claim 16 , wherein said electrolyte barrier further comprises a filler.  
     
     
         18 . A bipolar separator in accordance with  claim 17 , wherein said filler comprises a welding filler rod.  
     
     
         19 . A bipolar separator in accordance with  claim 15 , wherein said electrolyte barrier has a thickness of 10 to 100 μm and a width of at least 0.1 inches.  
     
     
         20 . A bipolar separator in accordance with  claim 14 , wherein: 
 said electrolyte barrier comprises one of a weld bead and a foil welded to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member; and    said electrolyte barrier further comprises a non-wettable coating: applied to said limited portion of the outer surface of said third pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said third pocket; and applied to said limited portion of the outer surface of said fourth pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said fourth pocket member.    
     
     
         21 . A bipolar separator in accordance with  claim 14 , wherein: 
 said third pocket member includes a back extension aligned with an end extension at said third end of said plate member, edge surfaces of said back extension of said third pocket member and said end extension at said third end of said plate member forming a wet-seal edge, and    and said fourth pocket member includes a back extension aligned with an end extension at said fourth end of said plate member, edge surfaces of said back extension of said fourth pocket member and said end extension at said fourth end of said plate member forming a wet-seal edge; and    wherein the edge surface of the back extension of said third pocket member forms a part of the limited portion of the outer surface of the third pocket member and the edge surface of the back extension of the fourth pocket member forms a part of the limited portion of the outer surface of the fourth pocket member.    
     
     
         22 . A bipolar separator in accordance with  claim 21 , wherein: 
 said electrolyte barrier comprises one of a weld bead, a foil welded to and a coating applied to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member.    
     
     
         23 . A bipolar separator in accordance with  claim 21:   said electrolyte barrier comprises one of a weld bead and a foil welded to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member; and    said electrolyte further comprises a non-wettable coating: applied to said limited portion of the outer surface of said third pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said third pocket; and applied to said limited portion of the outer surface of said fourth pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said fourth pocket member.    
     
     
         24 . A bipolar separator in accordance with  claim 21 , wherein; 
 said plate member is formed separately from said pocket members,    said first pocket member includes a back extension aligned with an end extension at said first end of said plate member;    and said second pocket member includes a back extension aligned with an end extension at said second end of said plate member; and    said back extensions of said first, second, third and fourth pocket member are welded to the end extensions at the first, second, third and fourth ends of said plate member.    
     
     
         25 . A fuel cell assembly comprising: 
 a fuel cell including an anode, a cathode and an electrolyte matrix disposed between said anode and said cathode;    an anode support abutting and supporting said anode, said anode support comprising: a first support member comprising a porous non-wettable material; and a second support member comprising a non-wettable metallic member having a plurality of through openings, wherein said first support member abuts and is joined with said second support member.    
     
     
         26 . A fuel cell assembly in accordance with  claim 25 , further comprising: 
 an anode current collector abutting said second support member and forming a plurality of passages for passing fuel gas and storing a reforming catalyst therein; and    a bipolar separator abutting said anode current collector for separating said fuel cell assembly from an adjacent fuel cell assembly.    
     
     
         27 . A fuel cell assembly in accordance with  claim 25 , wherein said first support member comprises one of a high porosity reticulated foam material and a porous sintered powder bed, and said second support member comprises one of a wire mesh, an expanded wire mesh and a perforated plate member.  
     
     
         28 . A fuel cell assembly in accordance with  claim 26 , wherein: 
 said first support member has a porosity of less than 70% and a mean pore size of at least 20 μm;    said through openings in said second support member are 20 mils or smaller in diameter and said openings comprise at least 40% of an area of said second support member; and    said first support member has a thickness of at least 2 mils and said second support member has a thickness of at least 5 mils.    
     
     
         29 . A fuel cell assembly in accordance with  claim 30 , wherein said first support member is joined with said second support member using a lamination process.  
     
     
         30 . A fuel cell assembly comprising: 
 a fuel cell including an anode, a cathode and an electrolyte matrix disposed between said anode and said cathode;    an anode current collector abutting said anode and forming a plurality of passages for passing fuel gas and storing a reforming catalyst therein; and    a bipolar separator abutting said anode current collector for separating said fuel cell assembly from an adjacent fuel cell assembly, said bipolar separator comprising a plate member having opposing first and second surfaces, said first surface being compatible with fuel gas and abutting said anode current collector and said second surface being compatible with oxidant gas and abutting said adjacent fuel cell assembly, said plate member having first and second opposing ends and third and fourth opposing ends;    first, second, third and fourth pocket members, said first and second pocket members being situated adjacent said first and second opposing ends of said plate member and extending outward of said first surface and then facing each other, and said third and fourth pocket members being situated adjacent said third and fourth opposing ends of said plate member and extending outward of said second surface and then facing each other;    said bipolar separator having first and second outer surface parts formed by the outer surfaces of said third and fourth pocket members, respectively;    and an electrolyte barrier comprising a non-wettable material situated on a limited portion of the outer surface of said third pocket member and a limited portion of the outer surface of said fourth pocket member.    
     
     
         31 . A fuel cell assembly in accordance with  claim 30 , wherein: 
 said limited portion of said outer surface of said third pocket member includes a surface portion at the end of said outer surface of said third pocket member closest said plate member; and    said limited portion of said outer surface of said fourth pocket member includes a surface portion at the end of said outer surface of said fourth pocket member closest said plate member.    
     
     
         32 . A fuel cell assembly in accordance with  claim 31 , wherein said electrolyte barrier comprises a non-wettable material comprising at least one of Ni, Cu, Ni alloy and Cu alloy.  
     
     
         33 . A fuel cell assembly in accordance with  claim 31 , wherein said electrolyte barrier comprises one of a weld bead, a foil welded to and a coating applied to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member.  
     
     
         34 . A fuel cell assembly in accordance with  claim 33 , wherein said electrolyte barrier further comprises a filler.  
     
     
         35 . A fuel cell assembly in accordance with  claim 34 , wherein said filler comprises a welding filler rod.  
     
     
         36 . A fuel cell assembly in accordance with  claim 33 , wherein said electrolyte barrier has a thickness of 10 to 100 μm and a width of at least 0.1 inches.  
     
     
         37 . A bipolar separator in accordance with  claim 31 , wherein: 
 said electrolyte barrier comprises one of a weld bead and a foil welded to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member; and    said electrolyte barrier further comprises a non-wettable coating: applied to said limited portion of the outer surface of said third pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said third pocket;    and applied to said limited portion of the outer surface of said fourth pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said fourth pocket member.    
     
     
         38 . A bipolar separator in accordance with  claim 31 , wherein: 
 said third pocket member includes a back extension aligned with an end extension at said third end of said plate member, edge surfaces of said back extension of said third pocket member and said end extension at said third end of said plate member forming a wet-seal edge, and    and said fourth pocket member includes a back extension aligned with an end extension at said fourth end of said plate member, edge surfaces of said back extension of said fourth pocket member and said end extension at said fourth end of said plate member forming a wet-seal edge; and    wherein the edge surface of the back extension of said third pocket member forms a part of the limited portion of the outer surface of the third pocket member and the edge surface of the back extension of the fourth pocket member forms a part of the limited portion of the outer surface of the fourth pocket member.    
     
     
         39 . A bipolar separator in accordance with  claim 38 , wherein: 
 said electrolyte barrier comprises one of a weld bead, a foil welded to and a coating applied to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member.    
     
     
         40 . A bipolar separator in accordance with  claim 38:   said electrolyte barrier comprises one of a weld bead and a foil welded to said limited portion of the outer surface of said third pocket member and to said limited portion of the outer surface of said fourth pocket member; and    said electrolyte further comprises a non-wettable coating: applied to said limited portion of the outer surface of said third pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said third pocket; and applied to said limited portion of the outer surface of said fourth pocket member and extending from said one of said weld bead and said foil welded to said limited portion of said outer surface of said fourth pocket member.    
     
     
         41 . A bipolar separator in accordance with  claim 38 , wherein; 
 said plate member is formed separately from said pocket members,    said first pocket member includes a back extension aligned with an end extension at said first end of said plate member;    and said second pocket member includes a back extension aligned with an end extension at said second end of said plate member; and    said back extensions of said first, second, third and fourth pocket member are welded to the end extensions at the first, second, third and fourth ends of said plate member.