Alkaline water electrolysis diaphragm and method of manufacturing same

Patent metadata

Field	Value
Publication number	US-10914014-B2
Application number	US-201615737451-A
Country	US
Kind code	B2
Filing date	May 16, 2016
Priority date	Jun 16, 2015
Publication date	Feb 9, 2021
Grant date	Feb 9, 2021

Abstract

A diaphragm includes a porous supporting body and a polymer porous membrane. When one of surfaces of the porous membrane is defined as a surface A, the other surface opposite to the surface A is defined as a surface B, a section of the porous membrane parallel to the surfaces A and B is defined as a section C, an average pore diameter on the surface A is defined as an average pore diameter D A , an average pore diameter on the surface B is defined as an average pore diameter D B , and an average pore diameter on the section C is defined as an average pore diameter D C , the average pore diameters D A and D B are substantially equal to each other, and the average pore diameter D C is larger than each of the average pore diameters D A and D B .

First claim

The invention claimed is:

1. An alkaline water electrolysis diaphragm separating an anode chamber and a cathode chamber of an alkaline water electrolyzer, the alkaline water electrolysis diaphragm comprising:
a sheet-shaped porous supporting body; and
a porous membrane containing organic polymer resin and impregnated in the supporting body, wherein:
a thickness of the porous membrane is larger than a thickness of the supporting body;
the porous membrane is impregnated in the supporting body over the entirety of the supporting body in a thickness direction of the supporting body;
a region of the porous membrane that is impregnated in the supporting body is defined as an impregnated region;
when one of membrane surfaces of the porous membrane is defined as a surface A, the other membrane surface of the porous membrane opposite to the surface A is defined as a surface B, a section of the porous membrane parallel to the surfaces A and B is defined as a section C, an average pore diameter of the porous membrane on the surface A is defined as an average pore diameter D A , an average pore diameter of the porous membrane on the surface B is defined as an average pore diameter D B , and an average pore diameter of the porous membrane on the section C is defined as an average pore diameter D C , the section C having the average pore diameter D C that is larger than each of the average pore diameters D A and D B which are substantially equal to each other is included in the porous membrane; and
when a section or surface parallel to the surfaces A and B of the porous membrane is defined as a surface S, and an average pore diameter of the porous membrane on the surface S is defined as an average pore diameter D S , the surface S having the average pore diameter D S that is not less than the average pore diameter D A or D B and smaller than 2 μm is included in the impregnated region.

2. The alkaline water electrolysis diaphragm according to claim 1 , wherein a ratio of the average pore diameter D B to the average pore diameter D A is 0.925 to 1.1.

3. The alkaline water electrolysis diaphragm according to claim 1 , wherein the surface B of the porous membrane and the other surface of the supporting body are substantially in flush with each other.

4. The alkaline water electrolysis diaphragm according to claim 1 , wherein the other surface of the supporting body is located on a flat surface which is parallel to the surface B and is included within a range from the surface B of the porous membrane to a position where the other surface of the supporting body is retreated from the surface B of the porous membrane in a thickness direction by not more than 5% of the thickness of the porous membrane.

5. The alkaline water electrolysis diaphragm according to claim 1 , wherein the other surface of the supporting body is located on a flat surface which is parallel to the surface B and is included within a range from the surface B of the porous membrane to a position where the other surface of the supporting body is advanced from the surface B of the porous membrane in a thickness direction by not more than a fiber diameter of the supporting body.

6. The alkaline water electrolysis diaphragm according to claim 1 , wherein porosity of the porous membrane is not less than 80% and not more than 90%.

7. The alkaline water electrolysis diaphragm according to claim 1 , wherein when a section of the porous membrane parallel to the surfaces A and B is defined as a section L, and an average pore diameter of the porous membrane on the section L is defined as an average pore diameter D L , the section L having the average pore diameter D L that is a largest average pore diameter of the porous membrane is included in the impregnated region of the porous membrane.

8. The alkaline water electrolysis diaphragm according to claim 1 , wherein the organic polymer resin is at least one selected from the group consisting of polysulfone, polyether sulfone, polyphenyl sulfone, polyvinylidene fluoride, polycarbonate, polytetrafluoroethylene, polypropylene, polyphenylene sulfide, polyketone, polyether ether ketone, polyimide, and polyether imide.

9. The alkaline water electrolysis diaphragm according to claim 1 , wherein the supporting body is nonwoven fabric, woven fabric, or composite fabric of nonwoven fabric and woven fabric, each of which is formed by fiber of at least one selected from the group consisting of polyphenylene sulfide, polypropylene, polysulfone, polyether sulfone, polyphenyl sulfone, fluorine-based resin, polyketone, polyimide, and polyether imide.

Assignees

• Kawasaki Heavy Ind Ltd
• De Nora Permelec Ltd
• Thyssenkrupp Uhde Chlorine Eng Japan Ltd
• Thyssenkruppp Uhde Chlorine Eng Japan Ltd

Inventors

• Ito Takafumi
• Shimomura Ikuo
• Kamei Yuji
• Manabe Akiyoshi
• Kato Akihiro
• Hashimoto Terumi

Classifications

• Y02E60/36

  Hydrogen production from non-carbon containing sources, e.g. by water electrolysis · CPC title

• C25B13/08 Primary

  based on organic materials · CPC title

• C25B13/02 Primary

  characterised by shape or form · CPC title

• C25B1/04

  by electrolysis of water · CPC title

• C25B9/73

  of the filter-press type · CPC title