Coating Process For Fuel Cell Components

• US 20070098908A1
• Filed: 10/05/2006
• Published: 05/03/2007
• Est. Priority Date: 10/17/2005
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Angelopoulos, Anastasios, Peters, Scott
• Granted Patent: US 9,640,805 B2
• Time in Patent Office: Days
• US Class Current: 427/407.1
• CPC Class Codes: H01M 8/0204 Non-porous and characterised by the material
• CPC Class Codes: H01M 8/0215 Glass; Ceramic materials
• CPC Class Codes: H01M 8/0221 Organic resins; Organic polymers
• CPC Class Codes: H01M 8/0228 in the form of layered or coated products
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 20/582 Recycling of unreacted starting or intermediate materials

Abstract

A process including coating a fuel cell component with an aqueous solution including a polyelectrolyte polymer.

Claims

1. A process comprising:

applying an aqueous solution comprising a polyelectrolyte polymer to a fuel cell component so that at least a portion of the polyelectrolyte polymer adheres to at least a portion of the component.

2. A process as set forth in claim 1 wherein the fuel cell component comprises a bipolar plate.

3. A process as set forth in claim 1 wherein the polyelectrolyte polymer includes cationic functional groups.

4. A process as set forth in claim 1 wherein the polyelectrolyte polymer includes anionic functional groups.

5. A process as set forth in claim 1 further comprising applying a second coating material to the polyelectrolyte polymer adhered to the component.

6. A process as set forth in claim 3 further comprising applying a second coating material including negative functional groups to the polyelectrolyte polymer adhered to the component and so that the negative functional groups and the positive functional groups form an ionic bond.

7. A process as set forth in claim 3 further comprising applying a hydrophilic coating to the polyelectrolyte polymer, and wherein the hydrophilic coating includes negative functional groups.

8. A process as set forth in claim 3 further comprising applying an aqueous solution comprising nanoparticles over the polyelectrolyte polymer adhered to the component.

9. A process as set forth in claim 3 further comprising applying an aqueous solution comprising siloxane nanoparticles.

10. A process as set forth in claim 5 wherein the second coating material comprises at least one of copolymers of acrylamide and quaternary ammonium salts;

polyamido-amine;

polyallylamine hydrochlorides;

epoxy based azo polymers or acrylic acid based azo polymers.

11. A process as set forth in claim 5 wherein the second coating material comprises at least one of SiO₂, HfO₂, ZrO₂, Al₂O₃, SnO₂, Ta₂O₅, Nb₂O₅, MoO₂, IrO₂, RuO₂, metastable oxynitrides, nonstoichiometric metal oxides, oxynitrides, and derivatives thereof including carbon chains or including carbon, or mixtures thereof.

12. A process as set forth in claim 1 further comprising applying a dispersion comprising nanoparticles to the polyelectrolyte polymer adhered to the component.

13. A process comprising:

(a) applying an aqueous polyelectrolyte polymer solution to a fuel cell component so that at least a portion of the polyelectrolyte polymer adheres to at least a portion of the component;

(b) removing any polyelectrolyte polymer not adhered to the fuel cell component;

(c) applying a second coating material to the polyelectrolyte polymer adhered to the component; and

(d) removing any of the second coating material not adhered to the polyelectrolyte polymer adhered to the component.

14. A process as set forth in claim 13 further comprising repeating (a-d) several times.

15. A process comprising:

(a) removing grease and contaminants from a fuel cell bipolar plate by immersing the plate in a pretreatment solution;

(b) rinsing the plate in a first bath of deionized water;

(c) rinsing the plate in a second bath of deionized water;

(d) immersing the plate in a first aqueous solution of a first polyelectrolyte polymer;

(e) rinsing the plate in a third bath of deionized water to remove any of the first polyelectrolyte polymer not adhered to the plate;

(f) rinsing the plate in a fourth bath of deionized water;

(g) immersing the plate in a second dispersion comprising a second coating material;

(h) rinsing the plate in a fourth bath of deionized water to remove any of the second coating material not adhered to the first polyelectrolyte polymer adhered to the plate;

(i) rinsing the plate in a fifth bath of deionized water;

(j) repeating (d-I) for three cycles;

(k) drying the plate.

16. A process as set forth in claim 15 wherein the second coating material comprises nanoparticles.

17. A process as set forth in claim 15 wherein the first polyelectrolyte polymer adhered to the plate includes cationic functional groups.

18. A process as set forth in claim 17 wherein the second coating material includes anionic functional groups.

19. A process as set forth in claim 17 wherein the second coating material comprises nanoparticles having anionic functional groups.

20. A process as set forth in claim 15 wherein the first polyelectrolyte polymer comprises at least one of:

a copolymer of acrylamide and quaternary ammonium salts;

a polyamido-amine;

a polyallylamine hydrochloride;

an epoxy based azo polymer;

or an acrylic acid based azo polymer.

21. A process comprising:

applying an aqueous solution comprising a polyelectrolyte polymer to a fuel cell component so that at least a portion of the polyelectrolyte polymer adheres to at least a portion of the component;

applying a second coating material to the polyelectrolyte polymer adhered to the fuel cell component.

22. A process as set forth in claim 21 wherein the fuel cell component comprises a bipolar plate.

23. A process as set forth in claim 21 wherein the polyelectrolyte polymer includes cationic functional groups.

24. A process as set forth in claim 21 wherein the polyelectrolyte polymer includes anionic functional groups.

25. A process as set forth in claim 21 wherein the second coating material comprises nanoparticles having a size ranging from about 2 to about 100 nanometers

26. A process as set forth in claim 21 wherein the second coating material comprises nanoparticles comprising inorganic or organic materials.

27. A process as set forth in claim 21 wherein the second coating material comprises nanoparticles comprising hydrophilic side chains.

28. A process as set forth in claim 21 wherein the second coating material comprises nanoparticles comprising 10 to 90 weight percent inorganic structures, 5 to 70 weigh percent hydrophilic, and 0 to 50 weight percent organic side chains having a functional group.

29. A process as set forth in claim 21 wherein the second coating material comprises at least one of an amino, sulfonate, sulfate, sulfite, sulfonamide, sulfoxide, carboxylate, polyol, polyether, phosphate, or phosphonate group.

30. A process as set forth in claim 21 wherein the second coating material comprises organic side chains having functional groups and wherein the functional groups of the organic side chains are epoxy, acryloxy, methacryloxy, glycidyloxy, allyl, vinyl, carboxyl, mercapto, hydroxyl, amide or amino, isocyano, hydroxy, or silanol groups.

31. A process as set forth in claim 21 wherein the fuel cell component comprises a substrate comprising at least one of a metal, polymeric material or electrically conductive composite material.

32. A process as set forth in claim 21 wherein the second coating material comprises at least one of SiO₂, HfO₂, ZrO₂, Al₂O₃, SnO₂, Ta₂O₅, Nb₂O₅, MoO₂, IrO₂, RuO₂, metastable oxynitrides, nonstoichiometric metal oxides, oxynitrides, and derivatives thereof including carbon chains or including carbon, or mixtures thereof.

33. A process as set forth in claim 21 wherein the second coating material comprises at least one Si—

O group, at least one polar group and at least one group including a saturated or unsaturated carbon chain.

34. A process as set forth in claim 21 wherein the second coating material comprises a polar group comprising at least one of a hydroxyl, halide, carboxyl, ketonic or aldehyde functional groups.

35. A process as set forth in claim 21 wherein the second coating material comprises Au, Ag, Ru, Rh, Pd, Re, Os, Ir, Pt, rare earth metals, alloys thereof, polymeric carbon or graphite.

36. A process as set forth in claim 21 wherein the second coating material comprises a Si—

O group and an Si—

R group wherein R includes a saturated or unsaturated carbon chain, and wherein the molar ratio of Si—

R groups to Si—

O groups ranges from ⅛

to ½

, preferably ¼

to ½

.

37. A process as set forth in claim 21 wherein the second coating material comprises a material derived from a siloxane.

38. A process as set forth in claim 21 wherein the second coating material comprises is derived from a material having the formula:

39. A process as set forth in claim 38 wherein at least one of R₁, R₂, R₃, R₄, R₅, or R₆ is a carbon chain with at least one carbon atom.