Electrode-membrane assembly and process for the preparation thereof

• US 20020106550A1
• Filed: 02/05/2002
• Published: 08/08/2002
• Est. Priority Date: 02/06/2001
• Status: Active Grant

• Current Assignee: De Nora Permelec Ltd. (Industrie De Nora S.p.A)
• Original Assignee: Permelec Electrode, Ltd. (Industrie De Nora S.p.A)
• Inventors: Shimamune, Takayuki, Kimoto, Kyoji, Nishiki, Yoshinori, Furuta, Tsuneto
• Granted Patent: US 6,869,714 B2
• Time in Patent Office: Days
• US Class Current: 429/42
• CPC Class Codes: H01M 4/8605 Porous electrodes
• CPC Class Codes: H01M 8/1004 characterised by membrane-electrode assemblies [MEA] H01M8/12 takes precedence
• CPC Class Codes: H01M 8/1011 Direct alcohol fuel cells [DAFC], e.g. direct methanol fuel cells [DMFC]
• 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 8/1088 Chemical modification, e.g. sulfonation
• CPC Class Codes: Y02E 60/36 Hydrogen production from non-carbon containing sources, e.g. by water electrolysis
• CPC Class Codes: Y02E 60/50 Fuel cells
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product
• CPC Class Codes: Y10T 29/49115 including coating or impregnating

Abstract

An electrode-membrane assembly comprising a pair of electrodes at least one of which is porous, and a thermoplastic resin membrane having a functional group capable of being modified to a free ion exchange group upon hydrolysis, which is interposed between the two electrodes and partly penetrates into the pores of the electrode. In this arrangement, the ion exchange membrane can be mechanically integrated to the anode and cathode to compensate for the insufficiency of mechanical strength of the ion exchange membrane. Thus, an electrode-membrane assembly which can be used in an industrial electrolytic cell or fuel cell is provided.

Claims

1. An electrode-membrane assembly comprising a pair of electrodes at least one of which is porous, and a thermoplastic resin membrane having a functional group capable of being modified to a free ion exchange group upon hydrolysis, which is interposed between said two electrodes and partly penetrates into the pores of said electrode.

2. The electrode-membrane assembly as claimed in claim 1, wherein said thermoplastic resin acts as a precursor of a fluorine-containing ion exchange membrane having a sulfonic acid group.

3. The electrode-membrane assembly as claimed in claim 1 wherein said thermoplastic resin membrane acts as a precursor of a fluorine-containing ion exchange membrane having a phosphonic acid group.

4. The electrode-membrane assembly as claimed in claim 1, wherein said thermoplastic resin is a copolymer of tetrafluoroethylene and a fluorovinyl compound having sulfonyl fluoride as a functional group.

5. An electrode-membrane assembly comprising a pair of electrodes at least one of which is porous, and an ion exchange membrane having a free ion exchange group, which is interposed between said two electrodes and partly penetrates into the pores of said electrode.

6. A fuel cell comprising an electrode-membrane assembly as claimed in claim 5.

7. A zero-gap type electrolytic cell comprising an electrode-membrane assembly as claimed in claim 5.

8. A process for the preparation of an electrode-membrane assembly which comprises interposing a thermoplastic resin membrane having a functional group capable of being modified to a free ion exchange group upon hydrolysis between a pair of electrodes at least one of which is porous, applying an external force to the assembly so that said thermoplastic resin membrane is deformed and partly allowed to penetrate into the pores of said porous electrode to make integration, and then subjecting the assembly to hydrolysis so that said functional group is released and modified to a free ion exchange group.