Fuel cell

• US 5,364,711 A
• Filed: 03/31/1993
• Issued: 11/15/1994
• Est. Priority Date: 04/01/1992
• Status: Expired due to Term

• Current Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Original Assignee: Kabushiki Kaisha Toshiba (Toshiba Corporation)
• Inventors: Hasimoto, Koji, Suzuki, Nobukazu, Sasaki, Kunihiko, Yamamoto, Masao, Yamada, Shuji, Uchida, Ken, Kanda, Motoya, Hongu, Akinori, Tsuruta, Shinji, Niki, Hirokazu, Kanazawa, Yoshiko, Kondou, Yuu
• Primary Examiner(s): KALAFUT, STEPHEN J
• Application Number:
  US08/041,427
• Time in Patent Office: 594 Days
• Field of Search: 429/15, 429/37, 429/38, 429/39, 929/30, 929/32
• US Class Current: 429/470
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 4/86 Inert electrodes with catalytic activity, e.g. for fuel cells
• CPC Class Codes: H01M 4/925 supported on carriers, e.g. powder carriers
• CPC Class Codes: H01M 4/926 on carbon or graphite
• CPC Class Codes: H01M 8/0204 Non-porous and characterised by the material
• CPC Class Codes: H01M 8/023 Porous and characterised by the material
• CPC Class Codes: H01M 8/0245 in the form of layered or coated products
• CPC Class Codes: H01M 8/0271 Sealing or supporting means around electrodes, matrices or membranes
• CPC Class Codes: H01M 8/04156 with product water removal
• CPC Class Codes: H01M 8/04186 of liquid-charged or electrolyte-charged reactants
• CPC Class Codes: H01M 8/04291 Arrangements for managing water in solid electrolyte fuel cell systems H01M8/04119 takes precedence
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/2455 with liquid, solid or electrolyte-charged reactants
• CPC Class Codes: H01M 8/247 Arrangements for tightening a stack, for accommodation of a stack in a tank or for assembling different tanks
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

In a fuel cell comprising a stack having superposed a plurality of electromotive parts composed of a fuel electrode, an oxidizing electrode, and an electrolyte layer nipped by the two electrodes and using a liquid fuel as the fuel for the fuel cell, this invention contemplates forming a liquid fuel introducing path destined to be directly exposed to the liquid fuel on terminal surfaces of the component parts of the electromotive parts in a direction perpendicular to the flow of an oxidizing gas along at least one of the outer peripheral surfaces of the stack including the terminal surface of the fuel electrode and lying parallelly to the flow of the oxidizing gas and enabling the liquid fuel in the liquid fuel introducing path to be supplied to the fuel electrodes by a capillary attraction. A fuel cell provided with means for recovery of the water produced by the cell reaction in the oxidizing electrodes is also disclosed, which fuel cell effects the removal of the water produced in the oxidizing electrodes during the operation of the fuel cell by a capillary attraction generated by two porous members.

Claims

1. A fuel cell comprising:

a stacked body composed of

a fuel electrode composed of porous material having capillaries,

an electrolyte plate stacked on said fuel electrode, and

an oxidizing electrode stacked on said electrolyte plate;

fuel supplying means for supplying liquid fuel to one lateral face of said stacked body, wherein said liquid fuel is diffused into said fuel electrode by capillary attraction; and

oxidizing gas supplying means for supplying oxidizing gas to another lateral face of said stacked body by flowing said oxidizing gas along the other lateral face of said oxidizing electrode.

2. The fuel cell according to claim 1, wherein said stacked body is of a rectangular polyhedron shape having two main faces and four lateral faces, said oxidizing gas flows from a first of the lateral faces of said stacked body to a second of the lateral faces of said stacked body which is parallel to said first lateral face, and said fuel supplying means is attached to a third or fourth of the lateral faces of said stacked body.

3. A fuel cell according to claim 1, wherein said fuel supplying means includes a liquid fuel introducing path formed on at least the one lateral face of said stacked body.

4. A fuel cell according to claim 1, wherein a plurality of said stacked bodies are superposed.

5. A fuel cell according to claim 4, wherein said fuel electrode has grooves in an electrode surface adjoined to said oxidizing electrode and said oxidizing gas flows through said grooves.

6. A fuel cell according to claim 4, wherein said oxidizing electrode has grooves in an electrode surface and oxidizing gas flow through said grooves.

7. A fuel cell according to claim 3, wherein said liquid fuel is introduced from a fuel storing tank to said liquid fuel introducing path by capillary attraction of said liquid fuel introducing path.

8. A fuel cell according to claim 1, wherein said capillaries of said fuel electrode have an oxide surface film.

9. A fuel cell according to claim 1, wherein said fuel electrode is composed of a substrate, particles composed of fuel oxidizing catalysts distributed on said substrate, and a proton conducting film deposited on surfaces of said particles.

10. A fuel cell according to claim 4, wherein a separator is interposed between each of the stacked bodies.

11. A fuel cell according to claim 10, wherein said fuel supplying means comprising a liquid fuel introducing path formed on at least the one of the lateral faces of said stacked body.

12. A fuel cell according to claim 10, wherein said separators have grooves formed in separator surfaces adjoined to said oxidizing electrodes, and oxidizing gas flows through said grooves.

13. The fuel cell according to claim 11, wherein said separators have grooves formed in separator surfaces adjoined to said fuel electrode, one end of said grooves being opened to said liquid fuel introducing path, and said liquid fuel flows through said grooves.

14. A fuel cell according to claim 11, wherein said liquid fuel is introduced from a fuel storing tank to said liquid introducing path by capillary attraction of said liquid fuel introducing path.

15. The fuel cell according to claim 10, wherein said capillaries of said fuel electrode have an oxide surface film.

16. A fuel cell according to claim 10, wherein said fuel electrode is composed of a substrate, particles composed of fuel oxidizing catalysts distributed on said substrate, and a proton conducting film deposited on surfaces of said particles.

18. A fuel cell according to claim 15 or claim 16 wherein said electrolyte plate further comprises a compound capable of ion exchange and a water absorbing and/or water retaining substance.

20. A fuel cell according to claim 1, wherein said fuel cell further comprising:

means for recovering water generated in said oxidizing electrode, wherein said recovering means comprise a first water absorbing means adjoined to said oxidizing electrode, and second water absorbing means adjoined to said first water absorbing means, wherein said second water absorbing means has a higher water absorbing ability than said first water absorbing means.

17. A fuel cell comprising:

a stack of superposed stacked bodies, each comprising a fuel electrode, an oxidizing electrode, and an electrolyte plate nipped between said fuel electrode and said oxidizing electrode,

wherein said stack is clamped at least in the direction of superposition of said stacked bodies with a material having rubber elasticity.

19. A fuel cell comprising a fuel electrode, an oxidizing electrode, an electrolyte layer nipped between said fuel electrode and said oxidizing electrode, and means for polarizing said fuel electrode anodically to refresh said fuel electrode.