ELECTROLYTE MATERIAL, LIQUID COMPOSITION AND MEMBRANE/ELECTRODE ASSEMBLY FOR POLYMER ELECTROLYTE FUEL CELL

• US 20110027688A1
• Filed: 07/26/2010
• Published: 02/03/2011
• Est. Priority Date: 07/31/2009
• Status: Active Grant

• Current Assignee: AGC, Inc.
• Original Assignee: Asahi Glass Company, Limited (AGC, Inc.)
• Inventors: Hommura, Satoru, Watakabe, Atsushi, Saito, Susumu, Shimohira, Tetsuji
• Granted Patent: US 8,597,855 B2
• Time in Patent Office: Days
• US Class Current: 429/483
• CPC Class Codes: C08F 214/182 Monomers containing fluorine not covered by the groups C08F214/20 - C08F214/28
• CPC Class Codes: H01B 1/122 Ionic conductors
• CPC Class Codes: H01M 8/0289 Means for holding the electrolyte solid polymer electrolytes H01M8/1018
• 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 8/1081 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

It is to provide a membrane/electrode assembly excellent in the power generation characteristics under low or no humidity conditions and under high humidity conditions, and an electrolyte material suitable for a catalyst layer of the membrane/electrode assembly.

It is to use an electrolyte material, which comprises a polymer (H) having ion exchange groups converted from precursor groups in a polymer (F) having repeating units (A) having a precursor group represented by the formula (g1) and repeating units (B) based on a perfluoromonomer having a 5-membered ring, and having a density of at most 2.03 g/cm³, the polymer (H) having an ion exchange capacity of from 1.3 to 2.3 meq/g dry resin:

wherein Q¹ and Q² are a perfluoroalkylene group having an etheric oxygen atom, or the like, and Y is F or the like.

Claims

1. An electrolyte material, which comprises a polymer (H) having ion exchange groups converted from precursor groups in the following polymer (F), the polymer (H) having an ion exchange capacity of from 1.3 to 2.3 meq/g dry resin:

polymer (F);

a polymer which has repeating units (A) based on a perfluoromonomer having a precursor group represented by the following formula (g1) and repeating units (B) based on a perfluoromonomer having a 5-membered ring or a perfluoromonomer capable of forming a 5-membered ring by cyclic polymerization, and which has a density of at most 2.03 g/cm³;

2. The electrolyte material according to claim 1, wherein at least one type of repeating units having ion exchange groups converted from the precursor groups in the repeating units (A) are repeating units represented by the following formula (u1):

3. The electrolyte material according to claim 1, wherein each of Q¹ and Q² which are independent of each other, is a C_1-6 perfluoroalkylene group which may have an etheric oxygen atom.

4. The electrolyte material according to claim 3, wherein at least one of Q¹ and Q² is a C_1-6 perfluoroalkylene group having an etheric oxygen atom.

5. The electrolyte material according to claim 1, wherein at least one type of the repeating units (B) are repeating units represented by the following formula (u21):

6. The electrolyte material according to claim 5, wherein R¹³ and R¹⁴ are a fluorine atom.

7. The electrolyte material according to claim 5, wherein at least one type of the repeating units represented by the formula (u21) are repeating units represented by the following formula (u21-1):

8. The electrolyte material according to claim 1, wherein at least one type of the repeating units (B) are repeating units represented by the following formula (u22):

9. The electrolyte material according to claim 8, wherein at least one type of the repeating units represented by the formula (u22) are repeating units represented by the following formula (u22-1):

10. The electrolyte material according to claim 1, wherein at least one type of the repeating units (B) are repeating units represented by the following formula (u24):

11. The electrolyte material according to claim 10, wherein at least one type of the repeating units represented by the formula (u24) are repeating units represented by the following formula (u24-1):

12. The electrolyte material according to claim 1, wherein the polymer (F) further has repeating units based on tetrafluoroethylene.

13. A liquid composition comprising a dispersion medium and the electrolyte material as defined in claim 1 dispersed in the dispersion medium, wherein the dispersion medium contains an organic solvent having a hydroxy group.

14. A membrane/electrode assembly for a polymer electrolyte fuel cell, which comprises an anode having a catalyst layer containing a proton conductive polymer, a cathode having a catalyst layer containing a proton conductive polymer, and a polymer electrolyte membrane disposed between the anode and the cathode, wherein the proton conductive polymer contained in the catalyst layer of at least one of the cathode and the anode is the electrolyte material as defined in claim 1.