Polymer electrolyte membrane

• US 20040121210A1
• Filed: 12/19/2002
• Published: 06/24/2004
• Est. Priority Date: 12/19/2002
• Status: Active Grant

• Current Assignee: 3M Innovative Properties Company (3M Company)
• Original Assignee: 3M Innovative Properties Company (3M Company)
• Inventors: Innes Moore, George Gower, Freemyer, Harold Todd, Hamrock, Steven Joseph, Rivard, Linda Mae
• Granted Patent: US 7,348,088 B2
• Time in Patent Office: Days
• US Class Current: 429/33
• CPC Class Codes: C08J 2327/12 containing fluorine atoms
• CPC Class Codes: C08J 5/225 containing fluorine
• CPC Class Codes: H01M 8/1023 having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes
• CPC Class Codes: H01M 8/1039 halogenated, e.g. sulfonated polyvinylidene fluorides
• CPC Class Codes: H01M 8/1067 characterised by their physical properties, e.g. porosity, ionic conductivity or thickness
• CPC Class Codes: H01M 8/1081 starting from solutions, dispersions or slurries exclusively of polymers
• 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 polymer electrolyte membrane is provided having a thickness of 90 microns or less and comprising a polymer, said polymer comprising a highly fluorinated backbone and recurring pendant groups according to the formula:

YOSO₂—CF₂—CF₂—CF₂—CF₂—O—[polymer backbone]  (I)

where Y is H⁺ or a monovalent cation such as an alkali metal cation. Typically, the membrane is a cast membrane. Typically, the polymer has a hydration product of greater than 22,000. Typically, the polymer has an equivalent weight of 800-1200.

Claims

1. A polymer electrolyte membrane having a thickness of 90 microns or less comprising a polymer, said polymer comprising a highly fluorinated backbone and pendant groups according to the formula:

YOSO₂—

CF₂—

CF₂—

CF₂—

CF₂—

O—

[polymer backbone] 

 

(I)

where Y is H⁺ or a monovalent cation.

2. The polymer electrolyte membrane according to claim 1 which is a cast membrane.

3. The polymer electrolyte membrane according to claim 2 having a thickness of 30 microns or less.

4. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has a hydration product of greater than 22,000.

5. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has a hydration product of greater than 23,000.

6. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has a hydration product of greater than 24,000.

7. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has an equivalent weight of between 800 and 1200.

8. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has an equivalent weight of between 900 and 1100.

9. The polymer electrolyte membrane according to any of claims 1-3 wherein said polymer has an equivalent weight of between 1000 and 1100.

10. The polymer electrolyte membrane according to claim 4 wherein said polymer has an equivalent weight of between 800 and 1200.

11. The polymer electrolyte membrane according to claim 4 wherein said polymer has an equivalent weight of between 900 and 1100.

12. The polymer electrolyte membrane according to claim 4 wherein said polymer has an equivalent weight of between 1000 and 1100.

13. The polymer electrolyte membrane according to claim 5 wherein said polymer has an equivalent weight of between 800 and 1200.

14. The polymer electrolyte membrane according to claim 5 wherein said polymer has an equivalent weight of between 900 and 1100.

15. The polymer electrolyte membrane according to claim 5 wherein said polymer has an equivalent weight of between 1000 and 1100.

16. The polymer electrolyte membrane according to claim 6 wherein said polymer has an equivalent weight of between 800 and 1200.

17. The polymer electrolyte membrane according to claim 6 wherein said polymer has an equivalent weight of between 900 and 1100.

18. The polymer electrolyte membrane according to claim 6 wherein said polymer has an equivalent weight of between 1000 and 1100.

19. A membrane electrode assembly comprising the polymer electrolyte membrane according to any of claims 1-3.