Perforated Or Foraminous Electrode Patents (Class 204/283)
  • Patent number: 6171721
    Abstract: A method for preparing a membrane for use in a fuel cell membrane electrode assembly includes the steps of providing an electrolyte membrane, and sputter-depositing a catalyst onto the electrolyte membrane. The sputter-deposited catalyst may be applied to multiple sides of the electrolyte membrane. A method for forming an electrode for use in a fuel cell membrane electrode assembly includes the steps of obtaining a catalyst, obtaining a backing, and sputter-depositing the catalyst onto the backing. The membranes and electrodes are useful for assembling fuel cells that include an anode electrode, a cathode electrode, a fuel supply, and an electrolyte membrane, wherein the electrolyte membrane includes a sputter-deposited catalyst, and the sputter-deposited catalyst is effective for sustaining a voltage across a membrane electrode assembly in the fuel cell.
    Type: Grant
    Filed: September 22, 1998
    Date of Patent: January 9, 2001
    Assignee: California Institute of Technology
    Inventors: Sekharipuram R. Narayanan, Barbara Jeffries-Nakamura, William Chun, Ron P. Ruiz, Thomas I. Valdez
  • Patent number: 6165333
    Abstract: A cathode assembly comprising a cathode, an ion-exchange membrane, and an electroconductive porous member permeable to gas and liquid sandwiched between the cathode and the membrane. The porous member may have, deposited on a part thereof, a catalyst active in hydrogen generation. The porous member preferably is in the form of a plate, sheet, fibers, web, paper, net, or sinter of any of these, and comprises at least a carbonaceous material and has a thickness of from 0.05 to 5 mm and a porosity of from 10 to 95%. Also disclosed is a method of reactivating a cathode assembly, which comprises conducting electrolysis using the cathode assembly until its activity decreases, and then depositing a catalyst active in hydrogen generation on the porous member.
    Type: Grant
    Filed: October 18, 1999
    Date of Patent: December 26, 2000
    Assignee: Permelec Electrode Ltd.
    Inventors: Masashi Tanaka, Shuji Nakamatsu, Yoshinori Nishiki
  • Patent number: 6165636
    Abstract: This invention pertains to improved formulations of platinum--molybdenum alloys for use as anode catalysts. These electrocatalysts find utility as a constituent of gas diffusion electrodes for use in fuel cells that operate at less than 180.degree. C. or in applications whereupon hydrogen is oxidized in the presence of carbon monoxide or other platinum inhibiting substances. The new formulations derive unexpected activity through creating highly dispersed alloy particles of up to approximately 300 .ANG. on carbon supports. The desired activity is achieved by carefully controlling the platinum to molybdenum ratio during preparation and judiciously selecting a proper loading of alloy on the carbon support.
    Type: Grant
    Filed: March 17, 1999
    Date of Patent: December 26, 2000
    Assignee: De Nora S.p.A.
    Inventors: James R. Giallombardo, Emory S. De Castro, Robert J. Allen
  • Patent number: 6159349
    Abstract: An electrolytic cell for producing a brine containing hydrogen peroxide is disclosed. Units for hydrogen peroxide production 3 and units for water electrolysis 2 are alternately arranged in the same electrolytic cell 1. Electrolysis is conducted while supplying hydrogen gas and oxygen gas generating in the respective water electrolysis units to a gas diffusion anode 11 and a gas diffusion cathode 13 of each unit for hydrogen peroxide production, to thereby obtain a brine containing hydrogen peroxide in a high concentration. Furthermore, because the anode of the hydrogen peroxide production units is a hydrogen gas diffusion anode having a reduced oxidizing ability, halogen ions contained in the seawater do not yield harmful halogenated organic substances.
    Type: Grant
    Filed: November 3, 1998
    Date of Patent: December 12, 2000
    Assignee: Permelec Electrode Ltd.
    Inventors: Shuhei Wakita, Yoshinori Nishiki, Takayuki Shimamune, Yasuo Nakajima, Masaaki Katoh, Yoshiyuki Kawaguchi, Takahiro Ashida, Masaharu Uno
  • Patent number: 6156166
    Abstract: An aqueous electrolysis cell for generation of gas includes an electrolysis container having an anode chamber and a cathode chamber separated from each other by a membrane. An anode and a cathode having permeability to gas and water are fitted on respective surfaces of the membrane. A first sealing element is fitted on the anode and the membrane to surround and seal circumference of the anode, one surface of the first sealing element being in tight contact with one surface of the membrane, and the first sealing element has an opening communicating with the anode. An anode current collector plate has one surface in tight contact with the other surface of the first sealing element, and a through-hole communicating with the opening of the first sealing element. A second sealing element has one surface in tight contact with the other surface of the anode current collector plate, and an opening communicating with the through-hole of the anode current collector plate.
    Type: Grant
    Filed: April 15, 1999
    Date of Patent: December 5, 2000
    Assignee: Take-One Office, Ltd.
    Inventors: Akihisa Koganezawa, Yukio Akahori
  • Patent number: 6149782
    Abstract: The invention relates to a novel rhodium sulfide catalyst for the reduction of oxygen in industrial electrolyzers. The catalyst is highly resistant towards corrosion and poisoning by organic species, thus resulting particularly suitable for use in aqueous hydrochloric acid electrolysis, when technical grade acid containing organic contaminants is employed.
    Type: Grant
    Filed: May 27, 1999
    Date of Patent: November 21, 2000
    Assignee: De Nora S.p.A
    Inventors: Robert J. Allen, James R. Giallombardo, Daniel Czerwiec, Emory S. De Castro, Khaleda Shaikh
  • Patent number: 6127059
    Abstract: A gas diffusion layer for a solid polymer electrolyte fuel cell having a solid polymer electrolyte and a catalyst layer disposed adjacent to the solid polymer electrolyte, where the gas diffusion layer includes a carbon fiber woven cloth having a surface and a coating of a fluororesin (such as polytetrafluoroethylene) containing carbon black on the surface, wherein the carbon fiber woven cloth is adapted to be disposed in the solid polymer electrolyte fuel cell such that the coating is adjacent to the catalyst layer in the solid polymer electrolyte fuel cell. Preferably, the coating penetrates no more than one-half the thickness of the carbon fiber woven cloth. Most preferably, the coating penetrates no more than one-third the thickness of the carbon fiber woven cloth. The carbon fiber woven cloth may be pre-treated with a water-repellent fluororesin (such as polytetrafluoroethylene), or with a mixture of a fluororesin and carbon black, to enhance water repellency.
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: October 3, 2000
    Assignee: Japan Gore-Tex Inc.
    Inventor: Hiroshi Kato
  • Patent number: 6126798
    Abstract: An anode includes an anode cup, a membrane and ion source material, the anode cup and membrane forming an enclosure in which the ion source material is located. The anode cup includes a base section having a central aperture and the membrane also has a central aperture. A jet is passed through the central apertures of the base section of the anode cup and through the membrane allowing plating solution to be directed at the center of a wafer being electroplated.
    Type: Grant
    Filed: November 13, 1997
    Date of Patent: October 3, 2000
    Assignees: Novellus Systems, Inc., International Business Machines Corp.
    Inventors: Jonathan David Reid, Robert J. Contolini, John Owen Dukovic
  • Patent number: 6117286
    Abstract: A zero-gap type electrolytic cell 11 characterized as having a hydrophilic liquid-permeable material 16 interposed between an ion-exchange membrane 12 and a gas diffusion cathode 17. The reaction product passes through the liquid-permeable material and disperses toward edges of the liquid-permeable material before being withdrawn. Hence, the withdrawal direction for the target reaction product is not opposite the feed direction for the reactant gas.
    Type: Grant
    Filed: October 16, 1998
    Date of Patent: September 12, 2000
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Koichi Aoki, Masashi Tanaka, Katsumi Hamaguchi, Yoshinori Nishiki
  • Patent number: 6113759
    Abstract: An anode assembly includes a perforated anode and an electrical contact assembly attached to the anode. A perforated anode holder holds the anode. The anode holder includes perforations at least in a bottom wall such that plating solution may flow through perforations in the anode holder and perforations in the anode. An anode isolator separates the anode and a cathode. The anode isolator includes at least one curvilinear surface. The contact assembly includes a closed or substantially closed cylinder member of titanium or titanium alloy, a copper lining or disk disposed within the cylinder, and a titanium or titanium alloy post fixed and in electrical engagement with the lining or disk.
    Type: Grant
    Filed: December 18, 1998
    Date of Patent: September 5, 2000
    Assignee: International Business Machines Corporation
    Inventor: Cyprian E. Uzoh
  • Patent number: 6110334
    Abstract: The invention relates to an electrolyte cell with an end anode and an end cathode and bipolar cell elements disposed between outer cell elements comprising these and electrically connected with them and connected in series one with the other, wherein each cell element comprises one or two gas diffusion electrode(s) of which one forms simultaneously the ceiling of the subjacent electrolyte chamber and the floor of the superjacent electrolyte chamber and the end anode and the anodes of the bipolar cell elements comprise a perforated, electrically well-conducting electrode structure, wherein each electrolyte chamber is charged with electrolyte and reaction gas, such as oxygen, and a particular mixture of electrolyte and the resulting product as well as residual reaction gas are drawn off from each electrolyte chamber, wherein the cell elements are combined in the form of a stack, that [sic] the end cathode and the cathodes of the bipolar cell elements comprise a perforated, electrically well-conducting support w
    Type: Grant
    Filed: June 4, 1998
    Date of Patent: August 29, 2000
    Inventor: Karl Lohrberg
  • Patent number: 6099704
    Abstract: This invention covers a cathodic element free from asbestos fibres that can be obtained by deposition after filtration through a porous medium of an aqueous suspension comprising electrically conductive fibres, at least one cationic polymer, at least one electocatalytic agent, at least one pore-forming agent and at least one binder selected from among the fluoropolymers. The invention also covers a method for preparing such a cathodic element.
    Type: Grant
    Filed: October 6, 1998
    Date of Patent: August 8, 2000
    Assignee: Chloralp
    Inventors: Gerard Bacquet, Frederic Kuntzburger
  • Patent number: 6086733
    Abstract: A high performance electrochemical cell is useful for recovery of metal from aqueous solutions. The electrochemical cell has a cathode assembly that includes a nonporous support member, a primary cathode, and a nonconductive or conductive porous material covering the primary cathode. An anode is spaced apart from the cathode assembly. Fluid is caused to flow through the porous material to the primary cathode, through openings or fluid collection channels in the nonporous support member, and uniformly out of the cell. Uniform and efficient deposition of metal is accomplished over the entire primary cathode because of modulation of fluid flow and increased mass transfer.
    Type: Grant
    Filed: October 27, 1998
    Date of Patent: July 11, 2000
    Assignee: Eastman Kodak Company
    Inventors: James J. Carey, Gary P. Wainwright, Stephen N. Lowery, Robert B. Call, Peter J. Kelch
  • Patent number: 6071386
    Abstract: An electrolysis apparatus has a number of membrane electrolysis cells. Each of the cells has a membrane formed on both sides with a contact layer. The apparatus, while it is compact in its design, is also suitable for comparatively high hydrogen production rates and can consequently be used particularly flexibly. A contact plate is respectively arranged on each contact layer. Each of the contact plates is formed, on its surface facing the contact layer assigned to it, with a system of ducts for the transport of water and/or gas.
    Type: Grant
    Filed: March 9, 1999
    Date of Patent: June 6, 2000
    Assignee: Siemens Aktiengesellschaft
    Inventor: Anwer Puthawala
  • Patent number: 6060196
    Abstract: A zinc alloy anode-based electrochemical cell, which generates gases and/or energy, is disclosed. The structure of the cell is such that a zinc alloy anode material is the integral part of housing and is in contact with an alkaline electrolyte containing minor amounts of corrosion inhibitors. The electrolyte which contains no zinc powder metal, may be in direct contact with the cathode thereby simplifying cell construction by elimination of a separator material. The cell is environmentally friendly, containing no mercury or cadmium or other toxic metals and is cost effective as it eliminates expensive amalgamated zinc powder and separator material.
    Type: Grant
    Filed: January 12, 1998
    Date of Patent: May 9, 2000
    Assignee: Ceramtec, Inc.
    Inventors: John H. Gordon, John J. McEvoy, Strahinja K. Zecevic, Ashok V. Joshi
  • Patent number: 6059944
    Abstract: A method of forming a liquid-permeable asbestos-free diaphragm on a cathode structure is described. The method comprises forming a liquid-permeable diaphragm base mat comprising fibrous synthetic polymeric material, e.g., polytetrafluoroethylene, on a cathode structure, e.g., a foraminous cathode; drawing a liquid slurry comprising an aqueous medium containing a wetting amount of surfactant and water-insoluble inorganic particulate material through the base mat, thereby to deposit said inorganic particulate material on and within the pre-formed base mat; and drying the resultant diaphragm at temperatures less than the temperature at which decomposition by-products of the surfactant are formed. The liquid slurry is substantially free of alkali metal halide and alkali metal hydroxide; and the inorganic particulate material comprises at least one oxide or silicate of a valve metal, e.g., zirconium oxide, having a median diameter of 0.
    Type: Grant
    Filed: July 29, 1998
    Date of Patent: May 9, 2000
    Assignee: PPG Industries Ohio, Inc.
    Inventors: Donald W. DuBois, Bernard A. Maloney, Jerry N. Kinney
  • Patent number: 6045668
    Abstract: The invention concerns a diaphragm chlor-alkali electrolysis cell comprising a cover, a conductive base for supporting the anodes and a cathode in the form of a box provided with internal wall, external wall and tubular fingers made of a mesh or perforated sheet covered with a porous diaphragm. One or more copper sheets for electric current distribution are fixed to the cathode external walls. The connection between the copper sheets and the cathode external walls is made by means of bolts with the interposition of a conductive and deformable element provided with residual elasticity under compression. The weldings for the assembling of the cathode walls are free from internal stresses.
    Type: Grant
    Filed: August 5, 1998
    Date of Patent: April 4, 2000
    Assignees: De Nora S.p.A., Elf Atochem S.A.
    Inventors: Jean-Claude Fort, Corrado Mojana, Pierluigi Borrione
  • Patent number: 6042959
    Abstract: A method is provided for making a membrane electrode that employs a composite membrane, which include both a porous membrane and an ion conducting electrolyte, by partially filling a porous membrane with an ion conducting electrolyte to form a partially filled membrane and then compressing the partially filled membrane with electrode particles so as to remove void volume from the partially filled membrane and embed the electrode particles in the partially filled membrane. The membrane electrode of this invention is suitable for use in electrochemical devices, including proton exchange membrane fuel cells, electrolyzers, chlor-alkali separation membranes, and the like.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: March 28, 2000
    Assignee: 3M Innovative Properties Company
    Inventors: Mark K. Debe, Thao Ngoc Pham, Andrew J. Steinbach
  • Patent number: 6042958
    Abstract: A novel composite membrane comprising a porous substrate of randomly orientated individual fibres and at least one ion conducting polymer, characterised in that the ion conducting polymer is embedded within the porous substrate, a process for its preparation and its use, particularly in fuel cells is disclosed.
    Type: Grant
    Filed: April 21, 1998
    Date of Patent: March 28, 2000
    Assignee: Johnson Matthey Public Limited Company
    Inventors: Jan Denton, John Malcolm Gascoyne, Graham Alan Hards, Thomas Robertson Ralph
  • Patent number: 6039853
    Abstract: The invention relates to an electrochemical half-cell (1) with a gas diffusion electrode (7) as cathode or anode wherein the gas chamber (6) is divided in particular into two or more gas pockets (6a, 6b, 6c) arranged one above another, the electrode chamber (2) of the half-cell (1) being divided into compartments (2a, 2b, 2c) which for the passage of the electrolyte (23), are connected to one another in cascade fashion via chutes (17), (18), (19).
    Type: Grant
    Filed: April 8, 1998
    Date of Patent: March 21, 2000
    Assignee: Bayer Aktiengesellschaft
    Inventors: Fritz Gestermann, Hans-Dieter Pinter, Karl-Ludwig Metzger, Heiko Herold
  • Patent number: 6024848
    Abstract: An improved electrochemical cell such as a fuel cell is disclosed including a porous support plate for enhancing transport of fluids throughout the cell and for enhancing capacitance and transient response capability of the cell. The electrochemical cell includes an electrolyte having opposed major surfaces with an anode and a cathode electrode supported in intimate contact with the opposed major surfaces. A porous support plate is secured adjacent each electrode, and each porous support plate includes a contact bi-layer in intimate contact with the electrode. Each contact bi-layer is comprised of a hydrophobic phase including a mixture of carbon black and a hydrophobic polymer defining a network of hydrophobic gas passages and each contact bi-layer also includes a hydrophilic phase including a mixture of carbon black and a proton exchange resin defining a network of hydrophilic liquid passages integrated throughout the contact bi-layer.
    Type: Grant
    Filed: April 15, 1998
    Date of Patent: February 15, 2000
    Assignee: International Fuel Cells, Corporation
    Inventors: Bryan Franz Dufner, Richard David Breault
  • Patent number: 6010317
    Abstract: An electrochemical cell module has an outer shell of conductive material defining a cavity, an electrolytic membrane located in the cavity, first and second pervious electrodes located on opposite sides of the membrane, and a seal member located between the second electrode and the outer shell. Contacts for connecting a power source across the electrodes are provided on the second electrode and on the outer shell on the same side of the membrane as the second electrode, and the outer shell provides a current collector for the first electrode without requiring any external leads across the module.
    Type: Grant
    Filed: September 1, 1998
    Date of Patent: January 4, 2000
    Assignee: Baxter International Inc.
    Inventors: Henri J. R. Maget, Robert J. Rosati
  • Patent number: 6007933
    Abstract: Fluid service and/or electrical conductivity for a fuel cell assembly is promoted. Open-faced flow channel(s) are formed in a flow field plate face, and extend in the flow field plate face between entry and exit fluid manifolds. A resilient gas diffusion layer is located between the flow field plate face and a membrane electrode assembly, fluidly serviced with the open-faced flow channel(s). The resilient gas diffusion layer is restrained against entering the open-faced flow channel(s) under a compressive force applied to the fuel cell assembly. In particular, a first side of a support member abuts the flow field plate face, and a second side of the support member abuts the resilient gas diffusion layer. The support member is formed with a plurality of openings extending between the first and second sides of the support member. In addition, a clamping pressure is maintained for an interface between the resilient gas diffusion layer and a portion of the membrane electrode assembly.
    Type: Grant
    Filed: April 27, 1998
    Date of Patent: December 28, 1999
    Assignee: Plug Power, L.L.C.
    Inventor: Daniel O. Jones
  • Patent number: 6007934
    Abstract: A platinum supported catalyst is disclosed for the anode in a PEM fuel cell with high resistance to poisoning by carbon monoxide. The catalyst contains the noble metals platinum and ruthenium on a finely divided, conductive support material. The two noble metals are not alloyed with each other and are present in highly dispersed form on the support material, wherein the crystallite size of the platinum is less than 2 nm and that of the ruthenium is less than 1 nm.
    Type: Grant
    Filed: May 19, 1998
    Date of Patent: December 28, 1999
    Assignee: Degussa Aktiengesellschaft
    Inventors: Emmanuel Auer, Andreas Freund, Thomas Lehmann, Karl-Anton Starz, Robert Schwarz, Udo Stenke
  • Patent number: 5998057
    Abstract: A particularly inexpensive, lightweight, homogeneous and porous gas diffusion electrode for polymer electrolyte membrane fuel cells is made in that carbonized carbon fiber nonwoven fabric is coated with a mixture of a soot suspension and a polytetrafluoroethylene suspension and sintered thereafter. The gas diffusion electrode may have a catalytically active layer applied thereto.
    Type: Grant
    Filed: October 5, 1998
    Date of Patent: December 7, 1999
    Assignee: Magnet-Motor Gesellschaft fur Magnetmotorische Technik GmbH
    Inventors: Arthur Koschany, Christian Lucas, Thomas Schwesinger
  • Patent number: 5985112
    Abstract: The general area of this invention relates to porous materials made from nanofiber packed beds. More particularly, the invention relates to altering the porosity or packing structure of a nanofiber packed bed structure by blending nanofibers with scaffold particulates having larger dimensions. For example, adding large diameter fibers to a nanotube packed bed to serve as a scaffolding to hold the smaller nanofibers apart and prevent the nanofiber bed structure from collapsing. This increases the average pore size of the mass by changing the pore size distribution and alters the packing structure of the packed bed. The increase in average pore size is caused by the creation of larger channels which improves the flow of liquids or gasses through these materials.
    Type: Grant
    Filed: April 6, 1998
    Date of Patent: November 16, 1999
    Assignee: Hyperion Catalysis International, Inc.
    Inventor: Alan B. Fischer
  • Patent number: 5964990
    Abstract: The device proposed for cleaning metal surfaces consist of pad (12, 34, 91) of insulating material held between a beak-shaped (11, 52, 94) electrode (10, 26, 46) and the metal surface (8) to be cleaned, plus a low-voltage a.c. power supply (2) which is connected via the other electrode to the metal (7). A pump supplies the pad with a highly corrosive, high-density, acid solution. The pad consists of a relatively thick hose or tape. The device has slots (36) into which the gases and vapors produced during cleaning are drawn by an extractor fan (40) and then passed through a washing bottle (41) where they are cleaned. The electrode may have various shapes, and it is possible to replace the tip (28, 94, 98). The electrode is preferably designed with bores through which the acid solution can be fed.
    Type: Grant
    Filed: May 26, 1998
    Date of Patent: October 12, 1999
    Assignees: Nitty-Gritty S.R.L., Nitty-Gritty GmbH
    Inventors: Stefano Muratori, Michele Lapelosa, Alessandro Alboni
  • Patent number: 5961795
    Abstract: The invention relates to an electrochemical cell which has an electrode, a membrane disposed in contact with one side of the electrode, and a resilient flow field disposed on the other side of the electrode. The resilient flow field provides uniform electrical contact with the electrode. Such a flow field is preferably an elastomer, which can be be made by molding techniques, thereby decreasing the cost and increasing the ease with which such a flow field may be manufactured. The resilient flow field of the present invention is particularly useful in converting anhydrous hydrogen halide directly to essentially dry halogen gas, such as anhydrous hydrogen chloride to chlorine gas, although it may be used in a cell which converts aqueous reactants.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: October 5, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Dennie Turin Mah, James Arthur Trainham, III, John Scott Newman, Clarence Garlan Law, Jr.
  • Patent number: 5958197
    Abstract: A gas diffusion electrode comprising an electrically conductive web provided on at least one side thereof with a coating containing a rhodium--rhodium oxide catalyst on a carbon black support and a method for the preparation of the rhodium--rhodium oxide catalyst.
    Type: Grant
    Filed: January 26, 1998
    Date of Patent: September 28, 1999
    Assignee: De Nora S.p.A.
    Inventors: Robert J. Allen, Daniel Czerwiec, James R. Giallombardo, Khaleda Shaikh
  • Patent number: 5938901
    Abstract: A gas-diffusion electrode (cathode) in contact with an ion-exchange membrane partitioning an electrolytic cell for producing caustic soda, etc., by electrolysis into an anode chamber and a cathode chamber (gas chamber). The gas-diffusion electrode is divided into plural electrode members in the horizontal direction with an interval provided between adjacent electrode members. Electrolyte guide plates may be disposed on the electrode members or between the adjacent electrode members. An aqueous caustic soda solution formed in the electrolysis smoothly is removed from the gas-diffusion electrode without clogging the electrode.
    Type: Grant
    Filed: July 9, 1997
    Date of Patent: August 17, 1999
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Yoshinori Nishiki, Masashi Tanaka, Takahiro Ashida, Shuhei Wakita
  • Patent number: 5932077
    Abstract: A wet process apparatus, e.g., plating cell for plating a flat substrate introduces a flow of electrolyte or other plating solution across the surface of the substrate to be plated. The substrate is mounted on a holder that is positioned on a door that swings between a horizontal open position and a vertical closed position. There is a circular opening in a front wall against which the door seats. The door can have a sealing ring that contacts the wall of the cell outside of the opening. A cathode ring disposed in a recess in the periphery of the opening makes electrical contact with the substrate. The cathode ring can include a thin metal thieving ring. A fluid-powered rotary blade or wiper within the plating chamber rotates to draw bubbles or other impurities from the substrate, and a megasonic transducer applies megasonic acoustic energy to the solution, e.g., at 0.2 to 5 Mhz. The cell can be used for electroless or galvanic plating.
    Type: Grant
    Filed: February 9, 1998
    Date of Patent: August 3, 1999
    Assignee: Reynolds Tech Fabricators, Inc.
    Inventor: H. Vincent Reynolds
  • Patent number: 5910378
    Abstract: Membrane electrode assemblies are described that include an ion conductive membrane a catalyst adjacent to the major surfaces of the ion conductive membrane and a porous particle filled polymer membrane adjacent to the ion conductive membrane. The catalyst can be disposed on the major surfaces of the ion conductive membrane. Preferably, the catalyst is disposed in nanostructures. The polymer film serving as the electrode backing layer preferably is processed by heating the particle loaded porous film to a temperature within about 20 degrees of the melting point of the polymer to decrease the Gurley value and the electrical resistivity. The MEAs can be produced in a continuous roll process. The MEAs can be used to produce fuel cells, electrolyzers and electrochemical reactors.
    Type: Grant
    Filed: October 10, 1997
    Date of Patent: June 8, 1999
    Assignee: Minnesota Mining and Manufacturing Company
    Inventors: Mark K. Debe, James M. Larson, William V. Balsimo, Andrew J. Steinbach, Raymond J. Ziegler
  • Patent number: 5879521
    Abstract: A gas-diffusion cathode disposed in contact with an ion-exchange membrane partitioning an electrolytic cell into an anode chamber and a cathode chamber, wherein at least one guide piece is disposed in the gas-diffusion cathode and a salt water electrolytic cell using the above-described gas-diffusion cathode. By using the above-described gas-diffusion cathode for salt water electrolysis, an aqueous caustic alkali solution formed descending in the direction of gravity in the cathode changes direction of movement by contact with a guide piece, whereby the decreased electrode performance resulting from the hindrance of the supply of raw material gas and the discharge of the gas formed caused by the retention of the descending caustic alkali solution is prevented and a large-sized electrolytic cell can be used without problems generally encountered in conventional electrolytic systems.
    Type: Grant
    Filed: September 3, 1997
    Date of Patent: March 9, 1999
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Takahiro Ashida, Masashi Tanaka, Shuhei Wakita, Yoshinori Nishiki
  • Patent number: 5879522
    Abstract: An electrolysis cell for the efficient production of hydrogen and oxygen is described which comprises a substantially closed housing defining therewithin anode and cathode chambers and having first and second inlets and outlets for flowing electrolyte through the anode and cathode chambers; an ion exchange membrane within the housing separating the anode chamber from the cathode chamber; first and second electrically conductive sheet members disposed within the respective anode and cathode chambers adjacent the membrane and substantially coextensive therewith; discrete electrically conducting ultramicroelectrode particles, preferably in the 5 to 10 micron size range, disposed within the anode and cathode chambers and defining the anode and cathode of the cell; and a source of DC electrical current operatively connected to the first and second sheet members.
    Type: Grant
    Filed: August 22, 1997
    Date of Patent: March 9, 1999
    Assignee: The United States of America as represented by the Secretary of the Air Force
    Inventors: Aly H. Shaaban, Eric K. Dobyne
  • Patent number: 5868912
    Abstract: The invention relates to an electrochemical cell which has an electrode, which may be either an anode or a cathode, and a membrane disposed in contact with one side of the electrode. An anode current bus is disposed on the other side of the anode, and a cathode current bus is disposed on the other side of the cathode. An anode current distributor collects current from the anode current bus and distributes it to the anode by electronic conduction, and a cathode current distributor collects current from the cathode and distributes it to the cathode bus by electronic conduction. The anode or the cathode current distributor is made of a metal which is treated by either nitriding, boriding or carbiding the metal in order to make the metal oxide growth resistant. In particular, the current distributor comprises tantalum that has been nitrided to form Ta.sub.2 N. The current distributor thus provides a barrier between the current bus and the electrode, and the anolyte, catholyte and products of the cell.
    Type: Grant
    Filed: November 3, 1997
    Date of Patent: February 9, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: David Lee Reichert, Charles Collmar Seastrom, Vinci Martinez Felix, Clarence Garlan Law, Jr., James Arthur Trainham, III, John Scott Newman
  • Patent number: 5863395
    Abstract: The invention relates to an electrochemical cell having an electrode with a catalyst layer and a gas diffusion layer. The cell also includes a mass flow field for directing fluid to and away from the electrode. An additional gas diffusion layer is disposed between the gas diffusion layer and the flow field. This increases the diffusion resistance of the fluid. The electrochemical cell of the present invention is particularly useful in a process for electrochemically converting anhydrous hydrogen halide to essentially dry halogen gas, where it is necessary to control and increase limiting current. It is also possible to use the additional gas diffusion layer in an aqueous process electrochemical cell.
    Type: Grant
    Filed: November 28, 1997
    Date of Patent: January 26, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Dennie Turin Mah, Clarence Garlan Law, Jr., James Arthur Trainham, III, John Scott Newman
  • Patent number: 5861222
    Abstract: A porous gas diffusion electrode for membrane fuel cells on an ion-conducting polymer. The electrode contains a finely divided electrocatalyst which is dispersed in a proton-conducting ionomer and has a total porosity of more than 40 to less than 75%. It supplies considerably improved performance data in comparison to known electrodes. The electrode can be produced by using pore-forming materials which are dissolved during the re-protonation of the ion-conducting polymers with sulfuric acid or are decomposed by the action of temperature.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: January 19, 1999
    Assignee: Degussa Aktiengesellschaft
    Inventors: Andreas Fischer, Hartmut Wendt, Ralf Zuber
  • Patent number: 5855748
    Abstract: The invention relates to an electrochemical cell which has an electrode, a membrane disposed in contact with one side of the electrode and a mass flow field disposed on the other side of the electrode for directing fluid to and away from the electrode. The mass flow field comprises glassy carbon. The cell of the present invention is particularly useful in converting anhydrous hydrogen halide, in particular, hydrogen fluoride, directly to essentially dry halogen gas, such as anhydrous hydrogen fluoride to fluorine gas.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: January 5, 1999
    Assignee: E. I. du Pont de Nemours and Company
    Inventors: Clarence Garlan Law, Jr., James Arthur Trainham, III, John Scott Newman
  • Patent number: 5837122
    Abstract: An inexpensive electrowinning electrode has a cathode that is a porous form made from conductive filaments, and an anode. The electrowinning process dissolves a contaminated metal stream into an electrolyte to form a solution flow of dissolve metal and contaminants. Next, the solution is oxidized. Then, the dissolved metals in the solution are plated onto the porous cathode.
    Type: Grant
    Filed: April 21, 1997
    Date of Patent: November 17, 1998
    Assignee: The Scientific Ecology Group, Inc.
    Inventors: Thomas Stephen Snyder, John Gregorie Wagner
  • Patent number: 5833821
    Abstract: An electrolyzer has an educt chamber, a membrane, a cathode-side product chamber, a porous cathode, a diaphragm, a porous anode, in which case a liquid electrolyte can be fixed in the pores of the anode and the cathode, and an anode-side product chamber. Between the membrane and the cathode-side product chamber, a first electrically conductive plate and, adjacent to the anode-side product gas chamber, a second electrically conductive plate, are situated. The two conductive plates are used for the current supply to and the current removal from the electrodes.
    Type: Grant
    Filed: December 2, 1996
    Date of Patent: November 10, 1998
    Assignee: Dornier GmbH
    Inventors: Ottmar Schmid, Werner Tillmetz
  • Patent number: 5827412
    Abstract: A liquid-permeable gas-diffusion cathode adapted for caustic soda electrolysis in contact with an ion-exchange membrane partitioning an electrolytic cell into an anode chamber and a cathode gas chamber. Plural horizontal concave grooves and/or convex portions are provided in an interval with one another on the surface of the gas-diffusion cathode facing the gas chamber. Plural vertical concave grooves may also be provided in an interval on the surface of the cathode crossing the horizontal grooves and/or convex portions. Aqueous caustic soda solution thus formed flows downward along the grooves, etc., without covering other portions of the cathode surface, and is easily released therefrom without clogging perforations in the gas-diffusion layer of the cathode.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: October 27, 1998
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Shuhei Wakita, Takahiro Ashida, Masashi Tanaka, Yoshinori Nishiki
  • Patent number: 5804055
    Abstract: An electrode, electrochemical cell, and electrochemical processes are disclosed. The electrode is a porous, multi-layered electrode which can have an element in flexible, strip form wound around a central, usually flat plate core, which core may serve as a current distributor. In any form, each layer can be represented by a very thin, highly flexible metal mesh. This can be a fine, as opposed to a coarse, mesh which has extremely thin strands and small voids. The electrode will have an active coating. For utilizing this electrode, the cell in one form will be a monopolar cell providing upward, parallel electrolyte flow through the porous, multi-layered electrode. A representative cell can have such electrode at least substantially filling an electrode chamber. The cells can be contained in a cell box that will provide the desired flow-through relationship for the electrolyte to the electrode.
    Type: Grant
    Filed: February 19, 1997
    Date of Patent: September 8, 1998
    Assignee: Eltech Systems Corporation
    Inventors: Richard J. Coin, Lynne M. Ernes, Andy W. Getsy, Edward M. Halko, Kenneth L. Hardee, Marilyn J. Niksa
  • Patent number: 5776328
    Abstract: Electrolyzer for the electrolysis of a solution of a salt for the production of a solution containing an acid and a solution of a base, said electrolyzer comprising at least one elementary cell divided into three compartments by two cation-exchange membranes, the first of said compartments contains the first of said membranes and a cathode for hydrogen evolution and the production of the base, a central compartment is defined by said cation-exchange membranes and has an inlet for the solution of the salt and has an outlet for the withdrawal of the solution containing the acid, a third compartment contains the second of said cation exchange membranes and an anode, said anode comprises a porous electrocatalytic sheet for hydrogen ionization and a porous rigid current collector, said third compartment further has an inlet for a hydrogen-containing gaseous stream and an outlet for the venting of the rest of gas characterized in that said current collector has a multiplicity of contact points and said porous elect
    Type: Grant
    Filed: May 24, 1996
    Date of Patent: July 7, 1998
    Assignee: De Nora Permelec S.p.A.
    Inventors: Carlo Traini, Giuseppe Faita
  • Patent number: 5766429
    Abstract: An electrolytic cell for producing sodium hydroxide, etc., which is partitioned by an ion-exchange membrane into an anode chamber and a cathode chamber, wherein at least one of a anode and a cathode is closely contacted to the ion-exchange membrane to form a gas diffusion electrode, and a current supplying means having guides for removing sodium hydroxide, etc., formed at the surface of the gas diffusion electrode is disposed therein closely contacting the gas diffusion electrode.By having a current supplying means having removing guides, sodium hydroxide formed at the surface of the gas diffusion electrode is separated therefrom and removed, whereby the supply of the raw material gas and removal of the produced gas can be smoothly performed without clogging perforations of the gas diffusion electrode with the sodium hydroxide.
    Type: Grant
    Filed: June 5, 1996
    Date of Patent: June 16, 1998
    Assignee: Permelec Electrode Ltd.
    Inventors: Takayuki Shimamune, Yoshinori Nishiki, Takahiro Ashida, Yasuo Nakajima
  • Patent number: 5736017
    Abstract: This invention has as its object to obtain a compact solid high polymer electrolytic module having a large electrolytic reaction capacity. An electrolytic membrane (20) is constituted in such a manner that strip-shaped anodes (23) and strip-shaped cathodes (22) are formed at a predetermined interval opposite to each other on both the surfaces of a belt-shaped solid high polymer electrolytic membrane (21). A frame (30) is constituted in such a manner that feeding terminals (33a, 33b) are formed on a pair of side edges (31a, 31b) of a frame member (31) having an opening (32) on one side. A plurality of frames (30) are stacked such that the openings (32) alternately face upward and downward. The electrolytic membrane (20) is folded at counter edges (31c) of the frames (30) and held between the adjacent frames (30) , thereby constituting a stereoscopically corrugated structure in a stacking direction of the frames (30).
    Type: Grant
    Filed: January 2, 1997
    Date of Patent: April 7, 1998
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventors: Tetsuo Moriguchi, Yoshiharu Takeuchi
  • Patent number: 5728485
    Abstract: Disclosed an electrode for a polymer electrolyte electrochemical cell which comprises catalyst supports carrying catalyst particles, a first solid polymer electrolyte layer insoluble in water and an organic solvent formed on the particles and a second solid polymer electrolyte layer insoluble or soluble in the organic solvent formed on part of the surface of the first solid polymer electrolyte layer and a process of preparing same.
    Type: Grant
    Filed: June 12, 1997
    Date of Patent: March 17, 1998
    Assignees: Tanaka Kikinzoku Kogyo K.K., Masahiro Watanabe, Stonehart Associates, Inc.
    Inventors: Masahiro Watanabe, Koichi Sakairi
  • Patent number: 5723086
    Abstract: The present invention relates to electrode membranes which comprise an ion-exchange material forming a core zone, with electrodes bonded thereto on both sides, the ion exchange material being formed from homopolymers soluble in solvents, or copolymers or mixtures thereof. The polymers must have at least one residue dissociable in ions. The electrode material is connected on either side of the core zone to the ion-exchange material to form an intimate contact between the electrode and the ion exchange materials, while the external sides of the electrode are pure electrode material. The electrode membranes are useful for forming fuel cells or electrolyzers.
    Type: Grant
    Filed: July 12, 1995
    Date of Patent: March 3, 1998
    Assignee: Fraunhofer-Gesellschaft Zur Forderung Der Angewandten Forschung E.V.
    Inventors: Konstantin Ledjeff, Roland Nolte, Michael Bauer, Falko Mahlendorf, Volker Peinecke
  • Patent number: 5720867
    Abstract: An electrolytic cell comprising bipolar electrodes is employed for electrochemical deposition of copper, zinc, lead, nickel or cobalt. An interior space is provided between the cathode side and the anode side of a bipolar electrode. The electrolyte can flow substantially without an obstruction through the interelectrode space between adjacent electrodes. The current densities in the interelectrode space amount to 800 to 8000 A/m.sup.2. Gas is evolved on the anode side of the bipolar electrodes and causes liquid to flow along the anode side. In the middle of the height of the anode side that liquid flow has a vertical component having a velocity of 5 to 100 cm/second. Electrolyte solution flows from the upper edge portion of the anode side to a return flow space, in which the solution flows downwardly. From the return flow space the solution is returned to the lower portion of the interelectrode space.
    Type: Grant
    Filed: October 27, 1995
    Date of Patent: February 24, 1998
    Assignee: Metallgesellschaft AG
    Inventors: Nikola Anastasijevic, Gerhard Jedlicka, Karl Lohrberg
  • Patent number: 5716437
    Abstract: An improved ink material, particularly for use in printing processes and its use in improved manufacturing processes for higher performance electrodes for application in fuel cells and other electrochemical devices is disclosed.
    Type: Grant
    Filed: March 7, 1996
    Date of Patent: February 10, 1998
    Assignee: Johnson Matthey Public Limited Company
    Inventors: Jan Denton, John M Gascoyne, David Thompsett
  • Patent number: 5695622
    Abstract: In the disclosed electrochemical cell for the production of an alkaline solution of peroxide, especially on-site production, the electrolyte is divided into an aqueous alkaline catholyte and an aqueous alkaline anolyte, and the cathode is a gas-diffusion electrode. The active material of the electrolyte side of the gas-diffusion cathode comprises a particulate catalyst support material having a surface area of about 50 to about 2000 m.sup.2 /g, and, deposited on the particles of this support material, 0.1 to 50 weight-%, based on the weight of the active layer, of gold or gold alloy particles having an average size >40 but less than about 200 .ANG.. These gold or gold alloy particles are substantially selectively catalytic for the reduction of oxygen to peroxide (e.g. HOO.sup..crclbar.). The electrolyte flow patterns are designed to avoid loss of peroxide resulting from oxidation at the anode. In the operation of the cell, a product with a hydroxyl:perhydroxyl ratio lees than 2:1 can be obtained.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: December 9, 1997
    Assignee: PSI Tecnology Co.
    Inventors: Mark E. Fraser, Alan S. Woodman, Everett B. Anderson, E. Jennings Taylor