Polymer electrode membrane for fuel, and membrane-electrode assembly and fuel cell system comprising the same

• US 20060154128A1
• Filed: 01/11/2006
• Published: 07/13/2006
• Est. Priority Date: 01/12/2005
• Status: Active Grant

• Current Assignee: Samsung SDI Company Limited
• Original Assignee: Samsung SDI Company Limited
• Inventors: Kim, Hee-Tak, Kweon, Ho-Jin
• Granted Patent: US 8,257,825 B2
• Time in Patent Office: Days
• US Class Current: 429/483
• CPC Class Codes: C08J 2379/06 Polyhydrazides; Polytriazoles; Polyamino-triazoles; Polyoxadiazoles
• CPC Class Codes: C08J 5/2275 Heterogeneous membranes
• CPC Class Codes: H01M 2300/0088 Composites
• CPC Class Codes: H01M 8/1023 having only carbon, e.g. polyarylenes, polystyrenes or polybutadiene-styrenes
• CPC Class Codes: H01M 8/1025 having only carbon and oxygen, e.g. polyethers, sulfonated polyetheretherketones [S-PEEK], sulfonated polysaccharides, sulfonated celluloses or sulfonated polyesters
• CPC Class Codes: H01M 8/1027 having carbon, oxygen and other atoms, e.g. sulfonated polyethersulfones [S-PES]
• CPC Class Codes: H01M 8/103 having nitrogen, e.g. sulfonated polybenzimidazoles [S-PBI], polybenzimidazoles with phosphoric acid, sulfonated polyamides [S-PA] or sulfonated polyphosphazenes [S-PPh]
• CPC Class Codes: H01M 8/1032 having sulfur, e.g. sulfonated-polyethersulfones [S-PES]
• CPC Class Codes: H01M 8/1039 halogenated, e.g. sulfonated polyvinylidene fluorides
• CPC Class Codes: H01M 8/106 characterised by the chemical composition of the porous support
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y10T 428/249954 With chemically effective material or specified gas other than air, N, or carbon dioxide in void-containing component
• CPC Class Codes: Y10T 428/249955 Void-containing component partially impregnated with adjacent component
• CPC Class Codes: Y10T 428/249956 Void-containing component is inorganic
• CPC Class Codes: Y10T 428/249957 Inorganic impregnant
• CPC Class Codes: Y10T 428/249964 Fibers of defined composition

Abstract

The present invention provides a polymer electrolyte membrane for a fuel cell, including a porous membrane including ceramic fibers crisscrossed in a network and pores formed by the ceramic fibers coalesced at intersection points, and a proton conductive polymer inside the pores.

Claims

1. A polymer membrane for a fuel cell, comprising:

a porous membrane comprising ceramic fibers crisscrossed in a network and pores formed by the ceramic fibers coalesced at the intersection points, and

a proton conductive polymer in the pores.

2. The polymer membrane of claim 1, wherein the size of the pores is from 0.01 to 3 μ

m.

3. The polymer membrane of claim 1, wherein the ceramic fiber is selected from the group consisting of silica fiber, alumina fiber, aluminosilicate fiber, aluminoborosilicate fiber, and mixtures thereof.

4. The polymer membrane of claim 1, wherein the amount of the ceramic fiber is 3 to 30 wt % of the porous membrane.

5. The polymer membrane of claim 1, wherein the ceramic fiber is coalesced at intersection points by a coalescing agent.

6. The polymer membrane of claim 5, wherein the coalescing agent is a compound selected from the group consisting of B₂O₃, BN, B₄C, SiB₄, SiB₆, and mixtures thereof.

7. The polymer membrane of claim 1, wherein the ceramic fiber is coated with a coalescing agent.

8. The polymer membrane of claim 1, wherein the proton conductive polymer is selected from the group consisting of perfluoro-based polymers, benzimidazole-based polymers, polyether-based polymers, polyimide-based polymers, polyetherimide-based polymers, polyamide-based polymers, polyphenylenesulfide-based polymers, polysulfone-based polymers, polyethersulfone-based polymers, polyetherketone-based polymers, polyether-etherketone-based polymers, polyphenylquinoxaline-based nolymers, and mixtures thereof.

9. A method of preparing a polymer membrane for a fuel cell comprising:

preparing a wet sheet by dispersing a ceramic fiber, a coalescing agent, organic fiber, and pulp in water, and then compressing them;

preparing a porous membrane by drying the wet sheet to prepare a film, and then heat-treating it to form pores thereon; and

adding a proton conductive polymer to the pores of the porous membrane.

10. The method of preparing a polymer membrane of claim 9, wherein the pores of the porous membrane are formed by oxidated organic fibers.

11. The method of preparing a polymer membrane of claim 9, wherein the coalescing agent is selected from the group consisting of B₂O₃, BN, B₄C, SiB₄, SiB₆, and mixtures thereof.

12. The method of preparing a polymer membrane of claim 9, wherein the coalescing agent is added in the proportion of 2 to 15 wt % of the amount of a ceramic fiber.

13. The method of preparing a polymer membrane of claim 9, wherein the organic fiber is selected from the group consisting of cellulose-based fibers, nylons, acryl polymers, polyester polymers, polyvinylalcohol resins, and mixtures thereof.

14. The method of preparing a polymer membrane of claim 9, wherein the organic fiber is present at 0.3 to 3 times as much volume as that of the ceramic fiber.

15. The method of preparing a polymer membrane of claim 9, wherein the proton conductive polymer is selected from the group consisting of a perfluoro-based polymers, benzimidazole-based polymers, polyether-based polymers, polyimide-based polymers, polyetherimide-based polymers, polyamide-based polymers, polyphenylenesulfide-based polymers, polysulfone-based polymers, polyethersulfone-based polymers, polyetherketone-based polymers, polyether-etherketone-based polymers, polyphenylquinoxaline-based polymers, and mixtures thereof.

16. A membrane-electrode assembly for a fuel cell, comprising:

a polymer electrolyte membrane comprising an anode and a cathode and a polymer electrolyte membrane interposed therebetween;

a porous membrane comprising ceramic fibers crisscrossing in a network and pores formed by ceramic fibers coalesced at intersection points; and

a proton conductive polymer inside the pores.

17. The membrane-electrode assembly of claim 16, wherein the proton conductive polymer is selected from the group consisting of a perfluoro-based polymers, benzimidazole-based polymers, polyether-based polymers, polyimide-based polymers, polyetherimide-based polymers, polyamide-based polymers, polyphenylenesulfide-based polymers, polysulfone-based polymers, polyethersulfone-based polymers, polyetherketone-based polymers, polyether-etherketone-based polymers, polyphenylquinoxaline-based polymers, and mixtures thereof.

18. A fuel cell system comprising:

at least one electricity generating element comprising the membrane-electrode assembly of claim 17 and a separator;

a fuel supplier for supplying a fuel to the electricity generating element; and

,

an oxidant supplier for supplying an oxidant to the electricity generating element.