Material fuel cell separator, fuel cell separator using same, fuel cell stack, and method of producing fuel cell separator material

• US 9,806,351 B2
• Filed: 08/09/2011
• Issued: 10/31/2017
• Est. Priority Date: 08/09/2011
• Status: Active Grant

• Current Assignee: JX Nippon Mining & Metals Corporation (ENEOS Holdings, Inc.)
• Original Assignee: JX Nippon Mining & Metals Corporation (ENEOS Holdings, Inc.)
• Inventors: Shibuya, Yoshitaka
• Primary Examiner(s): D'Aniello, Nicholas P
• Application Number:
  US14/237,673
• Publication Number:
  US 20140295322A1
• Time in Patent Office: 2,275 Days
• CPC Class Codes: H01M 8/0208 Alloys
• CPC Class Codes: H01M 8/0228 in the form of layered or coated products
• CPC Class Codes: Y02E 60/50 Fuel cells

Abstract

A material for fuel cell separator, wherein a surface layer 6 containing Au and Cr is formed on a surface of a Ti base 2, and an intermediate layer 2a containing Ti, O, Cr, and less than 20 atomic % of Au is present between the Ti base and the surface layer, a thickness of an area containing 65 atomic % or more of Au being 1.5 nm or more, a maximum concentration of Au being 80 atomic % or more, a coating amount of Au being 9000 to 40000 ng/cm², a ratio represented by (Au coating amount)/(Cr coating amount) being 10 or more, a coating amount of Cr being 200 ng/cm² or more, and in the intermediate layer having an area containing 10% or more of Ti, 10% or more of O and 20% or more of Cr being 1 nm or more.

Claims

1. A material for a fuel cell separator, comprising:

(a) a Ti base;

(b) a surface layer containing Au and Cr formed on a surface of the Ti base; and

(c) an intermediate layer containing Ti, O, Cr, and less than 20 atomic % of Au, wherein the intermediate layer is present between the Ti base and the surface layer;

wherein an area of the surface layer containing 65 atomic % or more of Au has a thickness of 1.5 nm to 27 nm,

a maximum concentration of Au in the surface layer is 85 to 99 weight %,

a coating amount of Au is 9000 to 40000 ng/cm²,

a ratio represented by (Au coating amount)/(Cr coating amount) is 10 to 80.4,

a coating amount of Cr is 200 ng/cm² to 5040 ng/cm², and

the intermediate layer has an area of 1 nm to 5 nm containing 10 atomic % or more of Ti, 10 atomic % or more of 0 and 20 atomic % or more of Cr.

2. The material for a fuel cell separator according to claim 1, wherein the Ti base is formed by coating a Ti coating with a thickness of 10 nm or more on a material other than Ti.

3. A polymer electrolyte fuel cell comprising the material for a fuel cell separator according to claim 1.

4. A direct methanol fuel cell comprising the material for a fuel cell separator according to claim 1.

5. A fuel cell separator comprising the material for a fuel cell separator according to claim 1, wherein a reaction gas flow path and/or a reaction liquid flow path is press-formed on the Ti base, and then the surface layer is formed.

6. A fuel cell separator comprising the material for a fuel cell separator according to claim 1, wherein the surface layer is formed on the Ti base, and then a reaction gas flow path and/or a reaction liquid flow path is press-formed.

7. A fuel cell stack comprising the material for a fuel cell separator according to claim 1.

8. A method of producing the material for a fuel cell separator according to claim 1, comprising:

dry film-forming Cr on the surface of the Ti base, and

dry film-forming Au thereon.

9. The method of producing the material for a fuel cell separator according claim 8, wherein the dry film-forming is sputtering.

10. A fuel cell stack comprising the fuel cell separator according to claim 5.

11. A fuel cell stack comprising the fuel cell separator according to claim 6.