Hydrogen power cell

• US 5,292,600 A
• Filed: 08/13/1992
• Issued: 03/08/1994
• Est. Priority Date: 08/13/1992
• Status: Expired due to Fees

• Current Assignee: H Power Corporation (Plug Power Inc.)
• Original Assignee: H Power Corporation (Plug Power Inc.)
• Inventors: Kaufman, Arthur
• Primary Examiner(s): GORGOS, KATHRYN L
• Application Number:
  US07/929,627
• Time in Patent Office: 572 Days
• Field of Search: 429/34, 429/38-39, 429/40
• US Class Current: 429/457
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 8/0213 Gas-impermeable carbon-containing materials
• CPC Class Codes: H01M 8/04291 Arrangements for managing water in solid electrolyte fuel cell systems H01M8/04119 takes precedence
• CPC Class Codes: H01M 8/1007 with both reactants being gaseous or vaporised H01M8/12 takes precedence
• CPC Class Codes: H01M 8/241 with solid or matrix-supported electrolytes
• CPC Class Codes: H01M 8/2457 with both reactants being gaseous or vaporised
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A hydrogen fuel cell comprising a cathode and an anode is disclosed. An electrolyte is disposed therebetween. The cathode is supplied with oxygen via a porous carbonaceous distribution plate. The anode is supplied with hydrogen. The operation of the fuel cell results in the generation of water. The carbonaceous member is oxidized sufficiently to impart hydrophilicity to the carbonaceous member while retaining mechanical strength and electrical properties.

Claims

1. An ion-exchange membrane electrolyte, water-producing, fuel cell for electricity generation by catalytic combustion of a gaseous hydrogenous fuel with gaseous oxygen leading to formation of water at the cathode, said fuel cell comprising:

a) an anode;

b) means to supply a gaseous hydrogenous fuel to said anode;

c) an oxygen-gas-pervious cathode;

d) an electrolyte disposed between said anode and said cathode; and

e) a water-pervious, electrically conductive, graphitic, oxygen-distribution member positioned adjacent said cathode to supply oxygen thereto and remove water therefrom, and having oxygen-distribution passages communicating with said cathode for the supply of oxygen thereto;

wherein said graphitic oxygen-distribution member is composed of a graphite material chemically activated to be hydrophilic, mechanically strong and electrically conductive, whereby water formed at said cathode is transported through said graphitic oxygen-distribution member with said oxygen-distribution passages remaining open for the distribution of oxygen to said cathode.

2. A fuel cell according to claim 1 wherein said oxygen-distribution member has a high hydrophilicity compared with untreated graphitic material, said hydrophilicity determined by observed rates of dispersion of water droplets introduced onto a surface of said graphitic material before and after chemical activation.

3. A fuel cell according to claim 1 wherein said oxygen-distribution member is composed of a fibrous graphite material surface-treated to have oxygenated species chemically bound to said fibrous graphite material.

4. A fuel cell according to claim 3 wherein said hydrophilic moieties include polar moieties being the product of oxidation of said fibrous graphite material.

5. A fuel cell according to claim 1 wherein said oxygen-distribution member is composed of a fibrous graphite material surface-treated to have carbon black material bound to said graphite material.

6. A fuel cell according to claim 1 wherein said anode, said cathode and said oxygen-distribution member constitute plates and are arranged in a stack.

7. A fuel cell according to claim 6 wherein said oxygen-distribution plate has a cathode-engaging face pressed into firm engagement with said cathode and said oxygen-distribution passages comprise grooves on said cathode-engaging face of said oxygen-distribution plate, said grooves defining ridges in said oxygen-distribution member, product water transported through said ridges away from said cathode.

8. A fuel cell assembly comprising a plurality of fuel cells according to claim 6, arranged face-to-face, in an extended stack and further comprising an electrically conductive separator plate between adjacent fuel cells in said extended stack.

9. A fuel cell according to claim 1 further comprising, for series-connection into a fuel cell assembly, a conductive separator secured to said oxygen-distribution member and a conductive hydrogenous-fuel distribution member secured to said conductive separator.

10. A fuel cell according to claim 1 wherein said anode comprises a graphitic member and said electrolyte comprises a proton-exchange membrane.

11. An ion-exchange member electrolyte, water-producing, fuel cell for electricity generation by catalytic combustion of a gaseous hydrogenous fuel with gaseous oxygen leading to formation of water at the cathode, said fuel cell comprising:

a) an anode;

b) means to supply a gaseous hydrogenous fuel to said anode;

c) an oxygen-gas-pervious cathode;

d) an electrolyte disposed between said anode and said cathode; and

e) a water-pervious, electrically conductive, graphitic, oxygen-distribution member positioned adjacent said cathode to supply oxygen thereto and remove water therefrom, and having oxygen-distribution passages communicating with said cathode for the supply of oxygen thereto;

wherein said graphitic oxygen-distribution member is composed of a fibrous graphite material surface treated to be hydrophilic, mechanically strong and electrically conductive, by having oxygenated species chemically bound to said fibrous graphite material and said oxygen-distribution member has a cathode-engaging face pressed into firm engagement with said cathode and said oxygen-distribution passages comprise grooves on said cathode-engaging face of said oxygen-distribution member, said grooves defining ridges in said oxygen-distribution member, product water transported through said ridges away from said cathode.