US4614575A
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US
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Polymeric hydrogel-containing gas diffusion electrodes and methods of using the same in electrochemical systems
Assignee: WALTER JUDA AND/OR WALTER JUDA ASSOCIATES
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Filing: 1984-11-19
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Granted: 1986-09-30
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Expires: 2004-11-19
Abstract
Abstract This invention is concerned with catalytic gas-diffusion structures such as electrodes and barriers comprising, as an integral part of a portion thereof, a non-ionic aqueous gel such as a polyvinyl alcohol, rendering said electrode impervious to gas percolation, while retaining electrolyte contact with the structures; and with methods of using said electrodes or barriers in a variety of electrochemical systems including electrolysis cells, fuel cells, batteries and others, as well as in metal-recovery systems involving no electricity.
Inventors
- 👤 Walter Juda
- 👤 Amiram B. Ilan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 06:25
CPC Classifications
H; H01; H01M; H01M4/00; H01M4/86; C; C25; C25B; C25B11/00; C25B11/02; C25B11/03; C25B11/031; C25B11/032; G; G01; G01N; G01N27/00; G01N27/26; G01N27/28; G01N27/30; G01N27/304; Y; Y02; Y02E; Y02E60/00; Y02E60/30; Y02E60/50
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
59 words
A catalytic gas-diffusion structure comprising electrode for use in an electrolytic cell having, as an integral part of a portion thereof, a substantially non-ionic, aqueous, polymeric gel, said gel being capable of preventing gas-percolation through said electrode and of restricting electrolyte access thereto to diffusional and electrochemical transport, and other portions of the electrode providing access to gas flow.
Claim 2
Dependent Claim
59 words
A catalytic gas-diffusion structure comprising electrode for use in an electrolytic cell having, as an integral part of a portion thereof, a substantially non-ionic, aqueous, polymeric gel, said gel being capable of preventing gas-percolation through said electrode and of restricting electrolyte access thereto to diffusional and electrochemical transport, and other portions of the electrode providing access to gas flow.
Claim 3
Dependent Claim
26 words
The structure of claim 1, wherein the gel of said electrode comprises at least one of a polymer and copolymer of a hydrophobic substantially non-ionic monomer.
Claim 4
Dependent Claim
32 words
The structure of claim 2, wherein said monomer is selected from glycol and glycerol monoacrylates and monomethacrylates, vinyl alcohol, ethylene oxide, propylene oxide acrylamide and methylacrylamide and their N-substituted derivatives and glutarimide.
Claim 5
Dependent Claim
12 words
The structure of claim 2, wherein at least one polymer is cross-linked.
Claim 6
Dependent Claim
12 words
Ihe structure of claim 1, wherein the gel is a polyvinyl alcohol.
Claim 7
Dependent Claim
93 words
An electrochemical system having, in combination, an aqueous electrolyte solution containing an electrode having opposing surfaces, at least one of which is in contact with said solution and having as an integral part of said one surface, a substantially non-ionic, aqueous, polymeric gel capable of preventing gas-percolation and of restricting electrolyte access thereto to diffusional and electrochemical transport, such that diffused electrolyte is dissolved in said gel, and means for applying an electrochemically active gas in contact with one of the opposite surface and edges of the electrode separated from said electrolyte solution.
Claim 8
Dependent Claim
93 words
An electrochemical system having, in combination, an aqueous electrolyte solution containing an electrode having opposing surfaces, at least one of which is in contact with said solution and having as an integral part of said one surface, a substantially non-ionic, aqueous, polymeric gel capable of preventing gas-percolation and of restricting electrolyte access thereto to diffusional and electrochemical transport, such that diffused electrolyte is dissolved in said gel, and means for applying an electrochemically active gas in contact with one of the opposite surface and edges of the electrode separated from said electrolyte solution.
Claim 9
Dependent Claim
35 words
In a gas diffusion-electrode assembly, gas diffusion electrode means having opposing surfaces, at least one of which is to contact an electrolyte, said one surface only being coated with an aqueous gel of polyvinyl alcohol.
Claim 10
Dependent Claim
35 words
In a gas diffusion-electrode assembly, gas diffusion electrode means having opposing surfaces, at least one of which is to contact an electrolyte, said one surface only being coated with an aqueous gel of polyvinyl alcohol.
Claim 11
Dependent Claim
48 words
In an electrochemical system comprising an aqueous electrolyte, a gas-diffusion electrode having opposing surfaces at least one of which is in contact with said electrolyte, said electrode having an aqueous non-ionic gas-impervious organic polymeric hydrophobic gel bonded to said one surface as an integral part of said electrode.
Claim 12
Dependent Claim
48 words
In an electrochemical system comprising an aqueous electrolyte, a gas-diffusion electrode having opposing surfaces at least one of which is in contact with said electrolyte, said electrode having an aqueous non-ionic gas-impervious organic polymeric hydrophobic gel bonded to said one surface as an integral part of said electrode.
Claim 13
Independent Claim
108 words
A method of rendering a catalyzed electrode of porous material impervious to the percolation therethrough of gas applied to one porous surface thereof and of restricting access of electrolyte to the other surface to diffusional and electrochemical transport, that comprises, coating the said other surface of the catalyzed electrode with an aqueous polyvinyl alcohol gel and embedding said gel within said electrode and sealing the same thereto, contacting said gel-coated catalyzed surface with the electrolyte, and introducing gas at said one surface, thereby reacting the gas introduced at the said one surface with the electrolyte held diffused into said gel at said other surface of the catalyzed electrode.
Claim 14
Independent Claim
108 words
A method of rendering a catalyzed electrode of porous material impervious to the percolation therethrough of gas applied to one porous surface thereof and of restricting access of electrolyte to the other surface to diffusional and electrochemical transport, that comprises, coating the said other surface of the catalyzed electrode with an aqueous polyvinyl alcohol gel and embedding said gel within said electrode and sealing the same thereto, contacting said gel-coated catalyzed surface with the electrolyte, and introducing gas at said one surface, thereby reacting the gas introduced at the said one surface with the electrolyte held diffused into said gel at said other surface of the catalyzed electrode.
Claim 15
Dependent Claim
33 words
A method as claimed in claim 9, and in which said electrode material comprises carbon cloth catalyzed with platinum particles and said gel is secured to, along and within the said other surface.
Claim 16
Dependent Claim
40 words
A method as claimed in claim 9, and in which said electrode is operated as an anode, said gas comprises hydrogen, and said electrolyte comprises an aqueous solution of ions of a metal that can be electroplated at a cathode.
Claim 17
Dependent Claim
66 words
In an electrolytic electrochemical cell employing a gas diffusion electrode, a method of restricting electrolyte access to and gas percolation through said electrode, that comprises, applying to one surface of the gas diffusion electrode an aqueous gel of polyvinyl alcohol and embedding the same therein while keeping the other surface gel-free, and disposing the electrode in the cell with said one surface contacting the electrolyte thereof.
Claim 18
Dependent Claim
66 words
In an electrolytic electrochemical cell employing a gas diffusion electrode, a method of restricting electrolyte access to and gas percolation through said electrode, that comprises, applying to one surface of the gas diffusion electrode an aqueous gel of polyvinyl alcohol and embedding the same therein while keeping the other surface gel-free, and disposing the electrode in the cell with said one surface contacting the electrolyte thereof.
Claim 19
Independent Claim
55 words
The method of anchoring a non-ionic substantially water-insoluble hydrogel on a catalytic gas diffusion electrode and which comprises the steps of applying a solution of a hydrogel-forming compound consisting of one of a monomer and a soluble polymer to a portion only of said electrode and polymerizing said compound to a substantially water-insoluble gas-impermeable hydrogel.
Claim 20
Independent Claim
55 words
The method of anchoring a non-ionic substantially water-insoluble hydrogel on a catalytic gas diffusion electrode and which comprises the steps of applying a solution of a hydrogel-forming compound consisting of one of a monomer and a soluble polymer to a portion only of said electrode and polymerizing said compound to a substantially water-insoluble gas-impermeable hydrogel.
Claim 21
Dependent Claim
41 words
The method of claim 13 wherein said solution comprises an aqueous isopropyl alcohol solution and wherein said compound is selected from vinyl alcohol and a soluble polyvinyl alcohol, thereby anchoring said hydrogel at least partly within the structure of said electrode.
Claim 22
Dependent Claim
10 words
The method of claim 14 wherein said compound is cross-linked.
References Cited (Backward Citations)
US4407905A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-09-29 | 1990-03-31 | 1990-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-29 | 1994-03-31 | 1994-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-29 | 1998-03-31 | 1998-09-30 | $7700.00 | Window Closed / Lapsed |