Patents by Inventor Subhash K. Dhar

Subhash K. Dhar has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20040248005
    Abstract: An active material for a negative electrode used in an electrochemical cell comprising a highly active, high surface area hydrogen storage material alloy which provides for high power output, fast activation, increased cycle life, and a hydrogen precharge in-situ. The highly active, high surface area hydrogen storage material is formed by first forming an alloy of a hydrogen storage alloy and aluminum and leaching the aluminum out of the alloy.
    Type: Application
    Filed: June 3, 2003
    Publication date: December 9, 2004
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Hong Wang, Boyko Aladjov, Meera Vijan, Subhash K. Dhar
  • Patent number: 6828057
    Abstract: A fuel cell utilizing parallel flow of a hydrogen stream, an oxygen stream, and an electrolyte solution with respect to the electrodes, while maintaining mechanical support within the fuel cell. The fuel cell utilizes framed electrodes to maintain a high air flow rate and low pressure throughout the fuel cell. The fuel cell is also designed to maintain mechanical support within the fuel cell while the electrodes expand and contract in response to the absorption of oxygen and hydrogen. Gas is predistributed by the compression plates and frames to supply the electrodes with high concentrations of oxygen from air.
    Type: Grant
    Filed: April 29, 2002
    Date of Patent: December 7, 2004
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Ana Menjak, Tom Hopper, Zdravko Menjak, Kevin Fok, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar
  • Publication number: 20040226830
    Abstract: A method for the production and storage of hydrogen. The hydrogen is produced via electrolysis and as the hydrogen is formed it is absorbed into a hydrogen storing cathode. Once the hydrogen storing cathode has become completely hydrided, it is shipped to end users as a metal hydride supply of hydrogen.
    Type: Application
    Filed: May 13, 2003
    Publication date: November 18, 2004
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Hong Wang, Subhash K. Dhar
  • Publication number: 20040219430
    Abstract: A conductive additive for the positive nickel electrode for electrochemical cells which provides increased performance by suppressing an oxygen evolution reaction occurring parallel to the oxidation of nickel hydroxide, increasing conductivity of the electrode and/or consuming oxygen produced as a result of the oxygen evolution reaction.
    Type: Application
    Filed: May 2, 2003
    Publication date: November 4, 2004
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Bora Tekkanat, Meera Vijan, Hong Wang, Subhash K. Dhar
  • Publication number: 20040217015
    Abstract: A method and system for electrochemically purifying an impure stream of hydrogen. Hydrogen is absorbed into a gas diffusion anode from the impure hydrogen stream and oxidized to form hydrogen ions and electrons which are released into an alkaline solution. An electrolytic cathode also positioned in the alkaline solution decomposes water to form hydrogen and hydroxyl ions which combine with the hydrogen ions to maintain equilibrium of the system.
    Type: Application
    Filed: May 1, 2003
    Publication date: November 4, 2004
    Inventors: Srinivasan Venkatesan, Hong Wang, Subhash K. Dhar, Stanford R. Ovshinsky
  • Patent number: 6790551
    Abstract: Fuel cell oxygen electrodes and instant startup fuel cells employing the oxygen electrode. The oxygen electrodes operate through the mechanism of redox couples which uniquely provide multiple degrees of freedom in selecting the operating voltages available for such fuel cells. Such oxygen electrodes provide the fuel cells in which they are used a “buffer” or “charge” of oxidizer available within the oxygen electrode at all times. The redox couple materials are modified to inhibit dissolution of the materials into the alkaline electrolyte of the fuel cell, and to match the gas phase kinetics of the active redox couple material with its electrochemical kinetics.
    Type: Grant
    Filed: September 10, 2002
    Date of Patent: September 14, 2004
    Assignee: Texaco Ovonic Fuel Cell UC
    Inventors: Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Stanford R. Ovshinsky
  • Publication number: 20040175615
    Abstract: A conductive additive for the positive nickel electrode for electrochemical cells which provides increased performance by suppressing an oxygen evolution reaction occurring parallel to the oxidation of nickel hydroxide, increasing conductivity of the electrode and/or consuming oxygen produced as a result of the oxygen evolution reaction.
    Type: Application
    Filed: March 3, 2003
    Publication date: September 9, 2004
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Bora Tekkanat, Meera Vijan, Hong Wang, Subhash K. Dhar
  • Publication number: 20040161652
    Abstract: An ambient temperature alkaline fuel cell pack supplied with a non-forced electrolyte and air stream which are circulated through the fuel cell pack via thermal convection resulting from heat produced during the reactions at the hydrogen and air electrodes.
    Type: Application
    Filed: February 12, 2003
    Publication date: August 19, 2004
    Inventors: Stanford R. Ovshinsky, Zdravko Menjak, Srinivasan Venkatesan, Latchezara Gradinarova, Ana Menjak, Hong Wang, Peter Faguy, Subhash K. Dhar
  • Publication number: 20040119194
    Abstract: A method for making an electrode for an electrochemical cell. The electrode is preferably made by mixing and heating an active electrode material with a polymeric binder in an extruder to form an active composition. The active composition is extruded out of the opening of the extruder as a sheet of material which may be affixed to a conductive support.
    Type: Application
    Filed: April 10, 2003
    Publication date: June 24, 2004
    Inventors: Boyko Aladjov, Stanford R. Ovshinsky, Srinivasan Venkatesan, Bora Tekkanat, Subhash K. Dhar
  • Publication number: 20040121228
    Abstract: An active composition for an electrode of an electrochemical cell. The active composition comprises an active electrode material and a conductive polymer. The electrochemical cell is preferably a battery cell or a fuel cell.
    Type: Application
    Filed: December 24, 2002
    Publication date: June 24, 2004
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Bora Tekkanat, Srinivasan Venkatesan, Subhash K. Dhar
  • Publication number: 20040101748
    Abstract: The present invention discloses a novel polymer alloy that may be used as a casing for alkaline storage batteries. The present invention discloses a sealed alkaline storage battery comprising a cell in which power generating elements and an alkaline electrolyte are accommodated in a battery casing of a synthetic resin. The polymer alloy comprises polyphenylene ether, polystyrene and glass fibers. The polymer alloy of the present invention comprises about 30 to 45 weight % polyphenylene ether, about 30 to 45 weight % polystyrene and about 10 to 40 weight % glass fibers. Preferably, the polymer alloy comprises 1 to 1 ratio of polyphenylene ether to polystyrene and the polystyrene is high impact polystyrene. Additionally, the polymer alloy may further include 0 to 15 weight % of an elastomer.
    Type: Application
    Filed: November 26, 2002
    Publication date: May 27, 2004
    Inventors: Rajeev Puttaiah, Ronald Himmler, Lin R. Higley, Marshall D. Muller, Subhash K. Dhar
  • Publication number: 20040074337
    Abstract: A process for preparing and passivating Raney nickel from a 50:50 aluminum-nickel alloy. The aluminum-nickel alloy is etched to form Raney nickel. The Raney nickel is then suspended in water and introduced to oxygen bubbled into the suspension thereby passivating the Raney nickel.
    Type: Application
    Filed: October 18, 2002
    Publication date: April 22, 2004
    Inventors: Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Stanford R. Ovshinsky
  • Publication number: 20040053109
    Abstract: Fuel cell oxygen electrode and instant startup fuel cells employing such oxygen electrode. The oxygen electrode operates through the mechanism of redox couples which uniquely provide multiple degrees of freedom in selecting the operating voltages available for such fuel cells. Such oxygen electrodes provide the fuel cells in which they are used a “buffer” or “charge” of oxidizer available within the oxygen electrode at all times.
    Type: Application
    Filed: September 16, 2003
    Publication date: March 18, 2004
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Kevin Fok, Thomas Hopper
  • Patent number: 6703156
    Abstract: Fuel cell oxygen electrode and instant startup fuel cells employing such oxygen electrode. The oxygen electrode operates through the mechanism of redox couples which uniquely provide multiple degrees of freedom in selecting the operating voltages available for such fuel cells. Such oxygen electrodes provide the fuel cells in which they are used a “buffer” or “charge” of oxidizer available within the oxygen electrode at all times.
    Type: Grant
    Filed: October 4, 2002
    Date of Patent: March 9, 2004
    Assignee: Texaco Ovonic Fuel Cell, LLC
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Kevin Fok, Thomas Hopper
  • Publication number: 20040031678
    Abstract: A double layered oxygen electrode impregnated with an active catalyst material and method of making. The design of the oxygen electrode promotes oxygen dissociation and absorption within the oxygen electrode. The oxygen electrode has differing layers of hydrophobicity which allow chemical impregnation of the active catalyst material into the oxygen electrode where the active catalyst material is needed most.
    Type: Application
    Filed: August 15, 2002
    Publication date: February 19, 2004
    Inventors: Srinivasan Venkatesan, Hong Wang, Boyko Aladjov, Subhash K. Dhar, Stanford R. Ovshinsky
  • Publication number: 20040002004
    Abstract: An active composition for fabricating positive electrodes, comprising a nickel hydroxide material, and a misch metal alloy. A nickel positive electrode and an electrochemical cell using this active composition.
    Type: Application
    Filed: March 19, 2003
    Publication date: January 1, 2004
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar
  • Publication number: 20030203274
    Abstract: A fuel cell utilizing parallel flow of a hydrogen stream, an oxygen stream, and an electrolyte solution with respect to the electrodes, while maintaining mechanical support within the fuel cell. The fuel cell utilizes framed electrodes to maintain a high air flow rate and low pressure throughout the fuel cell. The fuel cell is also designed to maintain mechanical support within the fuel cell while the electrodes expand and contract in response to the absorption of oxygen and hydrogen. Gas is predistributed by the compression plates and frames to supply the electrodes with high concentrations of oxygen from air.
    Type: Application
    Filed: April 29, 2002
    Publication date: October 30, 2003
    Inventors: Stanford R. Ovshinsky, Ana Menjak, Tom Hopper, Zdravko Menjak, Kevin Fok, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar
  • Publication number: 20030162074
    Abstract: A fuel cell utilizing parallel flow of a hydrogen stream, an oxygen stream, and an electrolyte solution with respect to the electrodes, while maintaining mechanical support within the fuel cell. The fuel cell contains multiple layers of electrodes which absorb and react hydrogen and oxygen. The fuel cell is designed to maintain mechanical support within the fuel cell while the electrodes expand and contract in response to the absorption of oxygen and hydrogen. The design of the fuel cell provides a substantially more compact design by not requiring space to allow for the expansion and contraction of the electrodes within the fuel cell.
    Type: Application
    Filed: February 28, 2002
    Publication date: August 28, 2003
    Inventors: Zdravko Menjak, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar, Stanford R. Ovshinsky
  • Patent number: 6605375
    Abstract: A method of activating a hydrogen storage alloy electrode. The method comprises the step of applying current cycles to the electrode where each current cycle includes a forward pulse effective to at least partially charge the electrode and a reverse pulse effective to at least partially discharge the electrode.
    Type: Grant
    Filed: February 28, 2001
    Date of Patent: August 12, 2003
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar, Thomas Hopper, Kevin Fok
  • Patent number: 6589686
    Abstract: A method of activating a metal hydride electrode of an alkaline fuel cell. The method comprises the step of applying current cycles to the anode where each current cycle includes a forward current effective to at least partially charge the electrode and a reverse current effective to at least partially discharge the electrode.
    Type: Grant
    Filed: January 8, 2002
    Date of Patent: July 8, 2003
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar, Thomas Hopper, Kevin Fok