Membrane electrode assembly comprising a catalyst migration barrier layer

Patent metadata

Field	Value
Publication number	US-9397357-B2
Application number	US-201113087476-A
Country	US
Kind code	B2
Filing date	Apr 15, 2011
Priority date	Apr 15, 2010
Publication date	Jul 19, 2016
Grant date	Jul 19, 2016

Abstract

A membrane electrode assembly for a fuel cell is disclosed, which comprises at least one porous ionomer containing layer disposed at the interface between the cathode electrocatalyst material and the ion exchange membrane of the fuel cell. The porous ionomer containing layer comprises a catalyst migration impeding compound. The membrane electrode assembly exhibits improved stability against Pt dissolution and Pt-band formation within the ion exchange membrane, hence having improved durability and lifetime performance.

First claim

What is claimed is:

1. A membrane electrode assembly for a fuel cell, said membrane electrode assembly comprising
(a) a porous anode gas diffusion layer;
(b) a porous cathode gas diffusion layer;
(c) an ion exchange membrane interposed between said porous anode gas diffusion layer and said porous cathode gas diffusion layer;
(d) an anode electrocatalyst material disposed at the interface between said porous anode gas diffusion layer and said ion exchange membrane;
(e) a cathode electrocatalyst material disposed on the surface of said porous cathode catalyst layer;
(f) at least one porous ionomer containing layer disposed at the interface between said cathode electrocatalyst material and said ion exchange membrane;
wherein said porous ionomer containing layer comprises a catalyst migration impeding compound different from the anode and cathode electrocatalyst material, wherein said catalyst migration impeding compound is a functionalized carbon, and wherein said functionalized carbon comprises carbon being functionalized with one or more metal ion sequestering moieties.

2. The membrane electrode assembly of claim 1 , wherein the porous ionomer containing layer is formed by one of a porous carbon layer or a porous composite-material matrix.

3. The membrane electrode assembly of claim 2 , wherein the porous composite-material matrix comprises one of a cold formed plastic (CFP) or expanded Polytetrafluoroethylene (PTFE).

4. A fuel cell comprising the membrane electrode assembly of claim 1 , wherein the cathode electrocatalyst material is elemental platinum (Pt).

5. A fuel cell comprising the membrane electrode assembly of claim 1 , wherein the anode and cathode electrocatalyst material is elemental platinum (Pt).

6. A fuel cell comprising the membrane electrode assembly of claim 1 , wherein the anode electrocatalyst material is elemental platinum (Pt).

7. The membrane electrode assembly of claim 1 , wherein the one or more metal ion sequestering moieties are linked to the carbon with an imidazole group as anchor group.

8. A membrane electrode assembly for a fuel cell, said membrane electrode assembly comprising
(a) a porous anode gas diffusion layer;
(b) a porous cathode gas diffusion layer;
(c) an ion exchange membrane interposed between said porous anode gas diffusion layer and said porous cathode gas diffusion layer;
(d) an anode electrocatalyst material disposed at the interface between said porous anode gas diffusion layer and said ion exchange membrane;
(e) a cathode electrocatalyst material disposed on the surface of said porous cathode catalyst layer;
(f) at least one porous ionomer containing layer disposed at the interface between said cathode electrocatalyst material and said ion exchange membrane;
wherein said porous ionomer containing layer comprises a catalyst migration impeding amount of a catalyst migration impeding compound different from the anode and cathode electrocatalyst material, wherein said catalyst migration impeding compound is a functionalized carbon, and wherein said functionalized carbon comprises carbon being functionalized with one or more metal ion sequestering moieties.

Assignees

• Bessarabov Dmitri
• Kundu Sumit
• Lee Stephen
• Mcdermid Scott
• Daimler Ag
• Ford Motor Co

Inventors

• Bessarabov Dmitri
• Kundu Sumit
• Lee Stephen
• Mcdermid Scott

Classifications

• H01M4/8657

  layered · CPC title

• H01M8/1004 Primary

  characterised by membrane-electrode assemblies [MEA] (H01M8/12 takes precedence) · CPC title

• H01M2300/0094

  in the form of layered products, e.g. coatings · CPC title

• H01M2300/0082

  Organic polymers · CPC title

• Y02E60/521

  Cross-Sectional Technologies · mapped topic