Gas diffusion electrode and fuel cell including same

• US 7,037,619 B2
• Filed: 09/27/2001
• Issued: 05/02/2006
• Est. Priority Date: 09/29/2000
• Status: Expired due to Term

• Current Assignee: Murata Manufacturing Co Limited
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Kanemitsu, Toshiaki, Yamaura, Kiyoshi
• Primary Examiner(s): YUAN, DAH WEI D
• Application Number:
  US09/964,910
• Publication Number:
  US 20020110725A1
• Time in Patent Office: 1,678 Days
• Field of Search: 429/12, 429/40, 429/44
• US Class Current: 429/480
• CPC Class Codes: B82Y 30/00 Nanotechnology for materials or surface science, e.g. nanocomposites
• CPC Class Codes: H01M 4/8605 Porous electrodes
• CPC Class Codes: H01M 4/8807 Gas diffusion layers
• CPC Class Codes: H01M 4/886 Powder spraying, e.g. wet or dry powder spraying, plasma spraying
• CPC Class Codes: H01M 4/96 Carbon-based electrodes
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] 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 fuel cell and method for preparation thereof, wherein the fuel cell is ready to manufacture, superior in cell performance, and includes a fuel electrode and an oxygen electrode facing each other with an electrode film positioned between the fuel electrode and the oxygen electrode, wherein at least one of the fuel electrode and the oxygen electrode contain a fibrous, or needle-like carbonaceous material and are directly formed on the electrode film.

Claims

1. A gas diffusion electrode operable within a fuel cell having a proton conductor, wherein the gas diffusion electrode is adhered directly to the proton conductor and consists essentially of a fibrous carbonaceous material, wherein the gas diffusion electrode comprises a thickness ranging from about 2 μ

m to about 4 μ

m.

2. The gas diffusion electrode as claimed in claim 1, wherein the fibrous carbonaceous material comprises carbon nanotubes.

3. The gas diffusion electrode as claimed in claim 1, wherein the fibrous carbonaceous material comprises vapor-grown carbon fibers.

4. The gas diffusion electrode as claimed in claim 1, wherein the fibrous carbonaceous material comprises a mixture of carbon nanotubes and vapor-grown carbon fibers.

5. The gas diffusion electrode as claimed in claim 4, wherein the mixture includes a ratio of carbon nanotubes to vapor-grown carbon fibers that ranges from about 0:

1 to about 9;

1.

16. The fuel cell as claimed in claim 4, wherein the mixture includes a ratio of the at least one type of carbon nanotube to the vapor-grown carbon fiber that ranges from about 1:

1 to about 4;

1.

6. A fuel cell, comprising:

a first electrode and a second electrode facing the first electrode; and

a proton conductor disposed between the first electrode and the second electrode, wherein at least one of the first electrode and the second electrode is adhered directly to the proton conductor and consists essentially of a fibrous carbonaceous material formed on the proton conductor, and wherein at least one of the first electrode and the second electrode comprises a thickness ranging from about 2 μ

m to about 4 μ

m.

7. The fuel cell as claimed in claim 6, wherein the fibrous carbonaceous material is selected from the group consisting of carbon nanotubes, vapor-grown carbon fibers and mixtures thereof.

8. The fuel cell as claimed in claim 7, wherein the fibrous carbonaceous material comprises a catalyst material in an amount of about 20% by weight or less.

9. The fuel cell as claimed in claim 8, wherein the catalyst material is selected from the group consisting of platinum and alloys thereof.

10. The fuel cell as claimed in claim 9, wherein the mixture includes a ratio of carbon nanotubes to vapor-grown carbon fibers that ranges from about 0:

1 to about 9;

1.

11. The fuel cell as claimed in claim 6, wherein the first electrode comprises a fuel electrode and the second electrode comprises an oxygen electrode.

12. A fuel cell, comprising:

a first electrode, a second electrode, and a proton conductor disposed between the first electrode and the second electrode, wherein at least one of the first electrode and the second a electrode is adhered directly to said proton conductor and consists essentially of carbonaceous material selected from the group consisting of at least one type of carbon nanotube, a graphite fibrous material, and mixtures thereof, and wherein at least one of the first electrode and the second electrode comprises a thickness ranging from about 2 μ

m to about 4 μ

m.

13. The fuel cell as claimed in claim 12, wherein the carbonaceous material consists essentially of a mixture of the at least one type of carbon nanotube and a graphite fibrous material.

14. The fuel cell as claimed in claim 13, wherein the graphite fibrous material includes a vapor-grown carbon fiber.

15. The fuel cell as claimed in claim 14, wherein the mixture includes a ratio of the at least one type of carbon nanotube to the vapor-grown carbon fiber that ranges from about 0:

1 to about 9;

1.

17. The fuel cell as claimed in claim 13, wherein the carbonaceous material contains a catalyst material in an amount of about 20% by weight or loss.