Fuel cell cathode and fuel cell system including a polymeric additive

Patent metadata

Field	Value
Publication number	US-11799088-B2
Application number	US-202217573089-A
Country	US
Kind code	B2
Filing date	Jan 11, 2022
Priority date	Jan 11, 2022
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

A cathode configured for use within a fuel cell system is provided. The cathode includes a cathode substrate. The cathode further includes a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C. The fluorocarbon polymer additive may be mixed with a catalyst ink coating or may be applied separately as a topcoat layer.

First claim

What is claimed is:

1. A cathode configured for use within a fuel cell system, the cathode comprising:
a cathode substrate; and
a coating disposed upon the cathode substrate including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C., wherein the cathode includes a catalyst ink, and wherein:
the coating includes a first coating configured as a topcoat layer, the cathode further comprises a second coating that includes the catalyst ink, and the second coating is disposed between the cathode substrate and the first coating.

2. The cathode of claim 1 , wherein the fluorocarbon polymer additive is configured for sintering at less than 150° C.

3. The cathode of claim 1 , wherein the fluorocarbon polymer additive is an amorphous polytetrafluoroethylene copolymer with fluorinated alicyclic monomers.

4. The cathode of claim 3 , wherein the amorphous polytetrafluoroethylene copolymer with the fluorinated alicyclic monomers is selected from the group consisting of tetrafluoroethylene, 4,5-difluoro-2,2-bis(trifluoromethyl)-1,3dioxole, and 2,2-bistrifluoromethyl-4,5-difluoro-1,3 dioxole.

5. The cathode of claim 1 , wherein the fluorocarbon polymer additive is a functionalized perfluoropolyether.

6. The cathode of claim 5 , wherein the functionalized perfluoropolyether is selected from the group consisting of a triethoxysilane terminated bifunctional perfluoropolyether; a diphosphate derivative based on a linear perfluoropolyether backbone; and a waterborne dispersion of an anionic polyurethane based on a perfluoropolyether backbone.

7. The cathode of claim 1 , wherein the fluorocarbon polymer additive is a polyvinylidene fluoride semicrystalline copolymer.

8. The cathode of claim 7 , wherein the polyvinylidene fluoride semicrystalline copolymer is selected from the group consisting of a vinylidene fluoride, a polyvinylidene fluoride: hexafluoro propylene copolymer latex, and a semicrystalline polyvinylidene fluoride: tetrafluoroethylene copolymer.

9. The cathode of claim 1 , wherein the fluorocarbon polymer additive is configured for sintering at less than 150° C. and the fluorocarbon polymer additive is an amorphous polytetrafluoroethylene copolymer with fluorinated alicyclic monomers.

10. The cathode of claim 1 , wherein the fluorocarbon polymer additive is configured for sintering at less than 150° C. and the fluorocarbon polymer additive is a functionalized perfluoropolyether.

11. The cathode of claim 1 , wherein the fluorocarbon polymer additive is configured for sintering at less than 150° C. and the fluorocarbon polymer additive is a polyvinylidene fluoride semicrystalline copolymer.

12. A fuel cell system comprising:
an anode;
a cathode including:
a cathode substrate; and

a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C., wherein the cathode includes a catalyst ink, and wherein:
the coating includes a first coating configured as a topcoat layer, the cathode further comprises a second coating that includes the catalyst ink, and the second coating is disposed between the cathode substrate and the first coating; and

a fuel cell membrane disposed between the anode and the cathode.

13. The fuel cell system of claim 12 , wherein the fluorocarbon polymer additive is configured for sintering at less than 150° C.

14. The fuel cell system of claim 12 , wherein the fluorocarbon polymer additive is an amorphous polytetrafluoroethylene copolymer with fluorinated alicyclic monomers.

15. The fuel cell system of claim 12 , wherein the fluorocarbon polymer additive is a functionalized perfluoropolyether.

16. The fuel cell system of claim 12 , wherein the fluorocarbon polymer additive is a polyvinylidene fluoride semicrystalline copolymer.

17. A vehicle comprising:
a powertrain system; and
a fuel cell system configured for providing electrical energy to the powertrain system, the fuel cell system including:
an anode;
a cathode including:
a cathode substrate; and

a coating disposed upon the cathode substrate and including a fluorocarbon polymer additive configured for sintering at a temperature of less than 200° C., wherein the cathode includes a catalyst ink, and wherein:
the coating includes a first coating configured as a topcoat layer, the cathode further comprises a second coating that includes the catalyst ink, and the second coating is disposed between the cathode substrate and the first coating; and

a fuel cell membrane disposed between the anode and the cathode.

18. The vehicle of claim 17 , wherein the fluorocarbon polymer additive is an amorphous polytetrafluoroethylene copolymer with fluorinated alicyclic monomers.

19. The vehicle of claim 17 , wherein the fluorocarbon polymer additive is a functionalized perfluoropolyether.

20. The vehicle of claim 17 , wherein the fluorocarbon polymer additive is a polyvinylidene fluoride semicrystalline copolymer.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Ramaswamy Nagappan
• Koestner Roland J
• Kumaraguru Swaminatha P

Classifications

• H01M4/8657 Primary

  layered · CPC title

• H01M4/8663 Primary

  Selection of inactive substances as ingredients for catalytic active masses, e.g. binders, fillers · CPC title

• H01M4/8828

  Coating with slurry or ink · CPC title

• H01M4/8885

  Sintering or firing · CPC title

• H01M2004/8689

  Positive electrodes · CPC title