Metal gas diffusion layer for fuel cells, and method for manufacturing the same

Patent metadata

Field	Value
Publication number	US-2016149227-A1
Application number	US-201414899618-A
Country	US
Kind code	A1
Filing date	May 22, 2014
Priority date	Jul 5, 2013
Publication date	May 26, 2016
Grant date	—

Abstract

A method for manufacturing a metal gas diffusion layer made of a metal porous body, the method includes forming a conductive layer of carbon film layer on the metal porous body, and forming a water-repellent layer on the metal porous body formed with the conductive layer. The forming a water-repellent layer includes coating a solution containing a fluorine resin which constitutes the water-repellent layer and a volatile component which does not constitute the water-repellent layer on the metal porous body, and heat-treating the metal porous body coated with the solution at or above a temperature at which a component which contains the volatile component and which does not constitute the water-repellent layer contained in the solution and less than a temperature at which an electrical resistance of the conductive layer is increased and electron conductivity is deteriorated to thereby form the water-repellent layer composed of the fluorine resin.

First claim

1 . A method for manufacturing a metal gas diffusion layer made of a metal porous body disposed between a polymer electrolyte membrane and a separator for a fuel cell, the method comprising:
forming a conductive layer of carbon film layer on the metal porous body; and forming a water-repellent layer on the metal porous body formed with the conductive layer, including coating a solution containing a fluorine resin which constitutes the water-repellent layer and a volatile component which does not constitute the water-repellent layer on the metal porous body, and heat-treating the metal porous body coated with the solution at or above temperature at which a component which contains the volatile component and which does not constitute the water-repellent layer contained in the solution and less than a temperature at which an electrical resistance of the conductive layer is increased and electron conductivity is deteriorated to thereby form the water-repellent layer composed of the fluorine resin.

2 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 1 , wherein the coating the solution on the metal porous body includes dipping the metal porous body in the solution.

3 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 2 , wherein the solution contains a surfactant representing a thermal decomposition component which does not constitute the water-repellent layer, and is heat treated at and above a thermal decomposition temperature of the surfactant in the heat-treating.

4 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 3 , wherein the solution is a water dispersion solution in which the fluorine resin, the surfactant, and water are mixed, and the volatile component is water.

5 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 4 , wherein a concentration of the fluorine resin is, by weight concentration in the water dispersion solution, in the range between 0.8 wt % and 6.4 wt %.

6 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 4 , wherein the fluorine resin is tetrafluoroethylene-hexafluoropropylene copolymer (FEP).

7 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 1 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

8 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 1 .

9 . The metal gas diffusion layer for a fuel cell as claimed in claim 8 , wherein the metal porous body includes wire mesh formed by weaving a plurality of wires.

10 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 5 , wherein the fluorine resin is tetrafluoroethylene-hexafluoropropylene copolymer (FEP).

11 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 2 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

12 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 3 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

13 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 4 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

14 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 5 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

15 . The method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 6 , wherein the conductive layer is a hard carbon coating layer made of diamond-like carbon, and an intensify ratio R(I D /I G ) which represents a ratio R of the D-band peak intensity I D to the G-band peak intensity I G measured by the Raman scattering spectroscopy is at or above 1.3.

16 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 2 .

17 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 3 .

18 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 4 .

19 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 5 .

20 . A metal gas diffusion layer for a fuel cell that is manufactured by the method for manufacturing a metal gas diffusion layer for a fuel cell as claimed in claim 6 .

Assignees

• Nissan Motor

Inventors

• Aotani Koichiro

Classifications

• H01M8/0234

  Carbonaceous material · CPC title

• H01M8/0245

  in the form of layered or coated products · CPC title

• H01M8/0239

  Organic resins; Organic polymers · CPC title

• H01M4/8605

  Porous electrodes · CPC title

• H01M8/0232

  Metals or alloys · CPC title