Fuel cell

• US 4,478,917 A
• Filed: 03/25/1983
• Issued: 10/23/1984
• Est. Priority Date: 03/26/1982
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Fujita, Kazunori, Horiba, Tatsuo, Iwamoto, Kazuo, Tamura, Kohki, Kawana, Hidejiro
• Primary Examiner(s): Hearn, Brian E.
• Assistant Examiner(s): Kalafut, Stephen J.
• Application Number:
  US06/479,097
• Time in Patent Office: 578 Days
• Field of Search: 429/33, 429/42
• US Class Current: 429/487
• CPC Class Codes: H01M 4/8668 Binders
• CPC Class Codes: H01M 4/881 Electrolytic membranes
• CPC Class Codes: H01M 4/8842 Coating using a catalyst salt precursor in solution followed by evaporation and reduction of the precursor
• CPC Class Codes: H01M 4/92 Metals of platinum group H01M4/94 , H01M4/9058 take precedence
• CPC Class Codes: H01M 8/0289 Means for holding the electrolyte solid polymer electrolytes H01M8/1018
• CPC Class Codes: H01M 8/08 Fuel cells with aqueous electrolytes
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1009 with one of the reactants being liquid, solid or liquid-charged H01M8/12 takes precedence
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A methanol fuel cell with an electrolyte ion exchange membrane integrated with an oxidizer electrode containing water-repellent particles on one side of the membrane and with a hydrophilic fuel electrode containing no water-repellent particles on the other side thereof and with less contact resistance between the ion exchange membrane and the electrodes and a three-phase boundary readily formable in the oxidizer electrode.

Claims

1. A fuel cell, which comprises an electrolyte ion exchange membrane, an oxidizer electrode, having water-repellent properties, comprising a mixture of noble metal particles of the periodic table, Group VIII and water repellent particles supported on one side of the ion exchange membrane, said mixture being formed on one side of the ion exchange membrane by dispersion plating, a hydrophilic fuel electrode containing noble metal particles of the periodic table, Group VIII and fixed to the opposite side of the membrane to the oxidizer electrode-formed side, an oxidizer supply means for supplying an oxidizer to the oxidizer electrode, and a methanol supply means for supplying methanol to the fuel electrode.

2. The fuel cell according to claim 1, wherein the ion exchange membrane is a strongly acidic ion exchange membrane.

3. The fuel cell according to claim 1, wherein the oxidizer is air.

4. The fuel cell according to claim 1, wherein the noble metal is at least one of platinum, ruthenium, palladium and rhodium of the periodic table, Group VIII.

5. The fuel cell according to claim 4 or 1, wherein the noble metal is platinum.

6. The fuel cell according to claim 1, wherein the water-repellent particles are at least one of styrene-divinylbenzene copolymer, polyethylene and fluorocarbon.

7. The fuel cell according to claim 6, wherein the fluorocarbon is polytetrafluoroethylene.

8. The fuel cell according to claim 1, wherein the noble metal particles and the water-repellent particles are supported on one side of the ion exchange membrane by contacting the said side of the membrane with a solution containing the noble metal of the periodic table, Group VIII and the water-repellent particles and contacting the opposite side with a reducing agent solution, thereby conducting chemical plating and fixing the noble metal particles and the water-repellent particles on the side contacted with the solution containing the noble metal and the water-repellent particles.

9. The fuel cell according to claim 8, wherein the noble metal particles are supported on the oxidizer electrode at a support amount of 1-6 mg/cm².

10. The fuel cell according to claim 8, wherein the water-repellent particles have particle sizes of 0.1-1 μ

m.

11. The fuel cell according to claim 8, wherein the noble metal particles on the oxidizer electrode have particle sizes of 60-80 Å

.

12. A fuel cell which comprises an electrolyte ion exchange membrane, an oxidizer electrode, having water-repellent properties, comprising a mixture of noble metal particles of the periodic table, Group VIII and water-repellent particles supported on one side of the ion exchange membrane, said mixture being formed on one side of the ion exchange membrane by dispersion plating, a hydrophilic fuel electrode comprising noble metal particles of the periodic table, Group VIII supported on the opposite side of the membrane to the oxidizer electrode-formed side by chemical plating, an oxidizer supply means for supplying an oxidizer to the oxidizer electrode and a methanol supply means for supplying methanol to the fuel electrode.

13. The fuel cell according to claim 12, wherein the noble metal particles are supported on the opposite side of the ion exchange membrane by contacting the side, on which the oxidizer electrode is to be formed, of the membrane with a reducing agent solution and contacting the opposite side with a solution containing the noble metal of the periodic table, Group VIII, thereby conducting chemical plating and fixing the noble metal particles on the side contacted with the solution containing the noble metal.

14. The fuel cell according to claim 13, wherein the noble metal consists of platinum and ruthenium.

15. The fuel cell according to claim 13, wherein the noble metal particles are supported at a support rate of 1-6 mg/cm².

16. The fuel cell according to claim 13, wherein the noble metal particles have particle sizes of 60-80 Å

.

17. The fuel cell according to claim 12, wherein the noble metal particles of the fuel electrode consist of platinum and ruthenium.

18. A fuel cell which comprises an electrolyte ion exchange membrane, an oxidizer electrode, having water-repellent properties, containing noble metal particles of the periodic table, Group VIII and water-repellent particles supported on one side of the membrane, said mixture being formed on one side of the ion exchange membrane by dispersion plating, a hydrophilic fuel electrode containing noble metal particles of the periodic table, Group VIII adjacent to the opposite side of the membrane to the oxidizer electrode-supported side, an oxidizer supply means for supplying an oxidizer to the oxidizer electrode, and a methanol supply means for supplying methanol to the fuel electrode.