SOLID ELECTROLYTE MEMBRANE, METHOD AND APPARATUS FOR PRODUCING THE SAME, MEMBRANE ELECTRODE ASSEMBLY AND FUEL CELL

• US 20090208807A1
• Filed: 07/06/2006
• Published: 08/20/2009
• Est. Priority Date: 07/07/2005
• Status: Abandoned Application

• Current Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Original Assignee: Fujifilm Corporation (Fujifilm Holdings Corporation)
• Inventors: Miyachi, Hiroshi, Takeda, Ryo
• Application Number:
  US11/994,907
• Publication Number:
  US 20090208807A1
• Time in Patent Office: Days
• US Class Current: 429/490
• CPC Class Codes: B01D 2323/20 Plasticizers
• CPC Class Codes: B01D 2325/22 Thermal or heat-resistance properties
• CPC Class Codes: B01D 2325/26 Electrical properties
• CPC Class Codes: B01D 67/00091 by evaporation
• CPC Class Codes: B01D 67/0011 Casting solutions therefor
• CPC Class Codes: B01D 67/0013 Casting processes
• CPC Class Codes: B01D 67/0088 Physical treatment with compounds, e.g. swelling, coating or impregnation
• CPC Class Codes: B01D 67/0095 Drying
• CPC Class Codes: B01D 69/06 Flat membranes
• CPC Class Codes: B01D 71/421 Polyacrylonitrile
• CPC Class Codes: B01D 71/68 Polysulfones; Polyethersulfones
• CPC Class Codes: B01D 71/82 characterised by the presence of specified groups, e.g. introduced by chemical after-treatment
• CPC Class Codes: B29C 41/28 by depositing flowable material on an endless belt
• CPC Class Codes: B29K 2081/06 PSU, i.e. polysulfones; PES, i.e. polyethersulfones or derivatives thereof
• CPC Class Codes: H01B 1/122 Ionic conductors
• CPC Class Codes: H01M 2300/0082 Organic polymers
• CPC Class Codes: H01M 8/1027 having carbon, oxygen and other atoms, e.g. sulfonated polyethersulfones [S-PES]
• 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 8/1081 starting from solutions, dispersions or slurries exclusively of polymers
• CPC Class Codes: H01M 8/1086 : After-treatment of the membrane other than by polymerisation
• 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

A dope (24) containing a solid electrolyte and an organic solvent is cast onto a web (111) to form a casting membrane (24a). The casting membrane (24a) is contacted with a first liquid (65a). A remaining solvent on the casting membrane (24a) is reduced. The casting membrane (24a) is peeled off as a membrane (62) from a belt (82). In a tenter device (64), the membrane (62) is dried while being stretched. Thereafter, the membrane (62) is contacted with a second liquid (66a). The membrane (62) is transported to a drying chamber (69) and dried while being supported by plural rollers (68). Since the membrane (62) is dried after substituting the first and second liquids (65a) and (66a) for the organic solvent, it becomes easy to evaporate and remove the remaining organic solvent in the membrane (62) together with the first and second liquids (65a) and (66a).

Claims

1. A producing method for a solid electrolyte membrane comprising the steps of:

(A) forming a casting membrane by casting a dope containing a solid electrolyte and an organic solvent onto a moving support;

(B) peeling said casting membrane from said support as a wet membrane containing said organic solvent;

(C) contacting at least one of said casting membrane and said wet membrane with a liquid which is a poor solvent of said solid electrolyte and having a lower boiling point than that of said organic solvent; and

(D) drying said wet membrane to form a solid electrolyte membrane.

2. A producing method according to claim 1, wherein said step (C) is performed for plural times before said step (D).

3. A producing method according to claim 2, wherein at least one of said casting membrane and said wet membrane contacted with said liquid is dried for at least one time between said plural step (C)s.

4. A producing method according to claim 2, wherein said liquid contacting with at least one of said casting membrane and said wet membrane has a lower boiling point than that of a preceding liquid.

5. A producing method according to claim 1, wherein in said step (C), at least one of said casting membrane and said wet membrane is immersed in said liquid.

6. A producing method according to claim 1, wherein said organic solvent is a mixture of a first component which is a poor solvent of said solid electrolyte, and a second component which is a good solvent of said solid electrolyte.

7. A producing method according to claim 6, wherein said weight ratio of said first component to said organic solvent is not less than 10% and less than 100%.

8. A producing method according to claim 6, wherein said first component includes alcohol having one to five carbons, and said second component includes dimethylsulfoxide.

9. A producing method according to claim 1, wherein said solid electrolyte is a hydrocarbon polymer.

10. A producing method according to claim 9, wherein said hydrocarbon polymer is an aromatic polymer having a sulfonic acid group.

11. A producing method according to claim 10, wherein said aromatic polymer is a copolymer represented by general formulae (I), (II) and (III) shown in a chemical formula 1.

(X is H or a monovalent cation species, Y is SO₂, Z is a structure shown in (I) or (II) in a chemical formula 2, n and m satisfy 0.1≦

n/(m+n)≦

0.5)

13. A solid electrolyte membrane used for a fuel cell produced by a method described in claim 1.

14. A membrane electrode assembly comprising:

a solid electrolyte membrane according to claim 13;

an anode electrode being adhered to one side of said solid electrolyte membrane for generating protons from hydrogen-containing substance supplied from outside; and

a cathode electrode being adhered to the other side of said solid electrolyte membrane for synthesizing water from said protons passed through said solid electrolyte membrane and a gas supplied from said outside.

15. A fuel cell comprising:

a membrane electrode assembly according to claim 14; and

current collectors attached to said electrodes of said membrane electrode assembly for transmitting electrons between said anode electrode and outside and between said cathode electrode and said outside.

12. A producing apparatus of a solid electrolyte membrane comprising:

a casting device for casting a dope containing a solid electrolyte and an organic solvent from a casting die onto a moving support to form a casting membrane;

a peeling device for peeling said casting membrane from said support as a wet membrane containing an organic solvent;

a membrane wetting device for contacting a liquid which is a poor solvent of said solid electrolyte and having a lower boiling point than that of said organic solvent with at least one of said casting membrane and said wet membrane; and

a drying device for drying said wet membrane to form a solid electrolyte membrane.