Electrode for a membrane-electrode assembly having improved water repellency and a method of manufacturing same

Patent metadata

Field	Value
Publication number	US-12362377-B2
Application number	US-202217750914-A
Country	US
Kind code	B2
Filing date	May 23, 2022
Priority date	May 25, 2021
Publication date	Jul 15, 2025
Grant date	Jul 15, 2025

Abstract

Disclosed is an electrode for a membrane-electrode assembly, in which a hydrophilic group and a hydrophobic portion of an ionomer are bonded to a catalyst so that the alignment of the hydrophilic group and the hydrophobic portion of the ionomer is controlled, and a method of manufacturing the same.

First claim

What is claimed is:

1. A method of manufacturing an electrode for a membrane-electrode assembly, the method comprising:
preparing a dispersion solution containing an ionomer having a hydrophilic group attached to an end of a side chain thereof;
adding a metal salt to the dispersion solution to manufacture a mixture;
adding a catalyst to the mixture to manufacture a catalyst slurry;
heat-treating the catalyst slurry;
treating the heat-treated catalyst slurry using acid; and
applying a resultant material to manufacture the electrode,
wherein metal ions of the metal salt are attached to the hydrophilic group of the ionomer in the mixture, and
wherein the catalyst slurry is heat-treated so that the hydrophilic group attached to the ionomer is aligned toward the catalyst.

2. The method of claim 1 , wherein the hydrophilic group includes at least one selected from the group consisting of a hydroxyl group, a carboxyl group, a nitro group, a sulfonic acid group, and a combination thereof.

3. The method of claim 1 , wherein the ionomer includes at least one selected from the group consisting of sulfonated polyimide (S—PI), sulfonated polyarylethersulfone (S-PAES), sulfonated polyetheretherketone (S-PEEK), perfluorosulfonic acid resin (perfluorosulfonic acid, PFSA), sulfonated polybenzimidazole (S—PBI), sulfonated polysulfone (S—PSU), sulfonated polystyrene (S—PS), sulfonated polyphosphazene, and a combination thereof.

4. The method of claim 1 , wherein the dispersion solution includes from 5 to 20 wt % of the ionomer.

5. The method of claim 1 , wherein the metal salt is added in an amount of from 50 to 200 parts by weight based on 100 parts by weight of the ionomer, thus manufacturing the mixture.

6. The method of claim 1 , wherein the catalyst is a platinum catalyst, or an alloy catalyst containing platinum and at least one transition metal selected from the group consisting of cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), chromium (Cr), and a combination thereof.

7. The method of claim 6 , wherein the catalyst is the alloy catalyst containing platinum and at least one transition metal selected from the group consisting of cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), chromium (Cr), and a combination thereof, and
wherein a metal salt includes a same kind of metal as the transition metal of the alloy catalyst.

8. The method of claim 1 , wherein the catalyst slurry includes from 50 to 90 wt % of the catalyst and from 10 to 50 wt % of the mixture.

9. The method of claim 1 , further comprising:
drying the catalyst slurry before the heat-treating.

10. The method of claim 1 , wherein the catalyst slurry is heat-treated for from 2 to 5 hours at a temperature that is higher by from 10 to 20° C. than a glass transition temperature (Tg) of the ionomer.

11. The method of claim 1 , wherein the heat-treated catalyst slurry is treated using the acid to remove the metal ions resulting from the metal salt.

12. An electrode for a membrane-electrode assembly, comprising:
a catalyst; and
an ionomer having a hydrophilic group attached to an end of a side chain thereof,
wherein the hydrophilic group is aligned toward the catalyst.

13. The electrode of claim 12 , wherein the hydrophilic group includes at least one selected from the group consisting of a hydroxyl group, a carboxyl group, a nitro group, a sulfonic acid group, and a combination thereof.

14. The electrode of claim 12 , wherein the ionomer includes at least one selected from the group consisting of sulfonated polyimide (S—PI), sulfonated polyarylethersulfone (S-PAES), sulfonated polyetheretherketone (S-PEEK), perfluorosulfonic acid resin (perfluorosulfonic acid, PFSA), sulfonated polybenzimidazole (S—PBI), sulfonated polysulfone (S—PSU), sulfonated polystyrene (S—PS), sulfonated polyphosphazene, and a combination thereof.

15. The electrode of claim 12 , wherein the catalyst includes a platinum catalyst, or an alloy catalyst of platinum and at least one selected from the group consisting of cobalt (Co), nickel (Ni), manganese (Mn), iron (Fe), chromium (Cr), and a combination thereof.

Assignees

• Hyundai Motor Co Ltd
• Kia Corp

Inventors

• Seol Su Won
• Cho Yoon Hwan
• Lee Ju Young

Classifications

• H01M8/0206

  Metals or alloys · CPC title

• H01M2008/1095

  Fuel cells with polymeric electrolytes · CPC title

• H01M8/1004 Primary

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

• H01M4/8668 Primary

  Binders · CPC title

• H01M4/8828 Primary

  Coating with slurry or ink · CPC title