Patents by Inventor Srinivasan Venkatesan

Srinivasan Venkatesan 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: 20030203273
    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 electrode assemblies having a frame overmolded around the electrode to maintain a flow rates 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.
    Type: Application
    Filed: October 31, 2002
    Publication date: October 30, 2003
    Inventors: Rajeev Puttaiah, Zdravko Menjak, Latchezara M. Gradinarova, Srinivasan Venkatesan, Boyko Aladjov, Subhash Dhar, Stanford R. Ovshinsky
  • 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
  • Patent number: 6620539
    Abstract: Fuel cell cathodes and instant startup fuel cells employing the cathode. The cathodes 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 cathodes provide the fuel cells in which they are used a “buffer” or “charge” of oxidizer available within the cathode at all times.
    Type: Grant
    Filed: March 1, 2001
    Date of Patent: September 16, 2003
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash Dhar
  • Patent number: 6617072
    Abstract: An active composition for an electrode of an electrochemical device. The active composition comprises an active electrode material, a carbon material, and a binder where the binder comprises an elastomeric polymer. Preferably, the active electrode material is nickel hydroxide, the carbon material is graphite and the elastomeric polymer is styrene-butadiene.
    Type: Grant
    Filed: November 27, 2001
    Date of Patent: September 9, 2003
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Srinivasan Venkatesan, Binay Prasad, Kenneth Laming, Boyko Aladjov
  • Patent number: 6613471
    Abstract: A hydrogen storage alloy active material for the anode of Ovonic instant startup/regenerative fuel cells. The active material includes a hydrogen storage alloy material with a water reactive chemical hydride additive, which, upon utilization of the active material in an anode of an alkaline electrolyte fuel cell, gives the anode added benefits, not attainable by using hydrogen storage alloy material alone. These added benefits include 1) precharge of the hydrogen storage material with hydrogen; 2) higher porosity/increased surface area/reduced electrode polarization at high currents; 3) simplified, faster activation of the hydrogen storage alloy; and 4) optionally, enhanced corrosion protection for the hydrogen storage alloy.
    Type: Grant
    Filed: October 31, 2001
    Date of Patent: September 2, 2003
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Thomas Hopper, Kevin Fok, Subhash 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
  • Publication number: 20030104280
    Abstract: An active composition for an electrode of an electrochemical device. The active composition comprises an active electrode material, a carbon material, and a binder where the binder comprises an elastomeric polymer. Preferably, the active electrode material is nickel hydroxide, the carbon material is graphite and the elastomeric polymer is styrene-butadiene.
    Type: Application
    Filed: November 27, 2001
    Publication date: June 5, 2003
    Inventors: Srinivasan Venkatesan, Binay Prasad, Kenneth Laming, Boyko Aladjov
  • Publication number: 20030059664
    Abstract: The present invention discloses a fuel cell, which incorporates a bipolar plate. The regenerative bipolar fuel cell of the present invention contains at least one hydrogen electrode in contact with a hydrogen stream and at least one oxygen electrode in contact with an oxygen stream. At least one electrolyte chamber is in contact with the hydrogen electrode and at least one electrolyte chamber is in contact with the oxygen electrode. The electrolyte chambers provide mechanical support within the fuel cell and provide an uninterrupted pathway for an electrolyte solution to contact the hydrogen electrode and the oxygen electrode, respectively. At least one bipolar plate is positioned between the hydrogen electrode and the oxygen electrode. The bipolar plate has a hydrogen side in contact with the hydrogen electrode and an oxygen side in contact with the oxygen electrode.
    Type: Application
    Filed: October 22, 2002
    Publication date: March 27, 2003
    Inventors: Zdravko Menjak, Srinivasan Venkatesan, Boyko Aladjov, Latchezara M. Gradinarova, Hong Wang, Stanford R. Ovshinsky, Subhash K. Dhar
  • Patent number: 6537700
    Abstract: An active material mixture for use in a paste for fabricating positive electrodes, comprising a nickel hydroxide material, and an additive material comprising at least one material selected from the group consisting of a misch metal or a misch metal alloy. A nickel positive electrode and an alkaline electrochemical cell using this active material mixture.
    Type: Grant
    Filed: November 7, 2000
    Date of Patent: March 25, 2003
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar
  • Publication number: 20030039879
    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: October 4, 2002
    Publication date: February 27, 2003
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Kevin Fok, Thomas Hopper
  • Publication number: 20030027034
    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: Application
    Filed: September 10, 2002
    Publication date: February 6, 2003
    Inventors: Srinivasan Venkatesan, Boyko Aladjov, Subhash K. Dhar, Stanford R. Ovshinsky
  • Patent number: 6503659
    Abstract: A layered hydrogen absorbing alloy electrode for an alkaline electrochemical cell. The layered electrode comprises a outer layer comprising a metal oxide, metal sulfide or mixtures thereof. The outer layer reduces the internal pressure of electrochemical cell.
    Type: Grant
    Filed: July 13, 1999
    Date of Patent: January 7, 2003
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Aladjov, Kevin Fok, Thomas J. Hopper, Lynn Taylor
  • Publication number: 20020187394
    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: June 28, 2002
    Publication date: December 12, 2002
    Inventors: Stanford R. Ovhsinsky, Srinivasan Venkatesan, Boyko Aladjov, Subhash Dhar, Kevin Fok, Thomas Hopper
  • Patent number: 6492057
    Abstract: An alkaline electrochemical cell having a hydrogen absorbing alloy negative electrode. The electrochemical cell comprises an alkaline electrolyte comprising an additive material which reduces cell pressure by decreasing hydrogen gas evolution.
    Type: Grant
    Filed: April 14, 1999
    Date of Patent: December 10, 2002
    Assignee: Ovonic Battery Company, Inc.
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Alajov, Kevin Fok, Thomas J. Hopper, James L. Strebe
  • Publication number: 20020182493
    Abstract: Mechanically and thermally improved rechargeable batteries, modules and fluid-cooled battery pack systems. The battery is prismatic in shape with an optimized thickness to width to height aspect ratio which provides the battery with balanced optimal properties when compared with prismatic batteries lacking this optimized aspect ratio. The optimized thickness, width and height allow for maximum capacity and power output, while eliminating deleterious side affects. The battery case design allows for unidirectional expansion which is readily compensated for by applying external mechanical compression counter to that direction. In the module, the batteries are bound within a module bundling/compression means under external mechanical compression which is optimized to balance outward pressure due to expansion and provide additional inward compression to reduce the distance between the positive and negative electrodes, thereby increasing overall battery power.
    Type: Application
    Filed: April 12, 2002
    Publication date: December 5, 2002
    Inventors: Stanford R. Ovshinsky, Dennis A. Corrigan, Srinivasan Venkatesan, Subhash K. Dhar, Arthur Holland, Donn Fillmore, Lin Higley, Philippe Gow, Ronald Himmler, Nick Karditsas, Kenneth Laming, Anthony Osgood
  • Publication number: 20020127466
    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: Application
    Filed: January 8, 2002
    Publication date: September 12, 2002
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar, Thomas Hopper, Kevin Fok
  • Patent number: 6447942
    Abstract: A fuel cell which has the ability to start up instantly and can accept recaptured energy such as that of regenerative braking by operating in reverse as an electrolyzer. The instant startup fuel cells have increased efficiency and power availability (higher voltage and current) and a dramatic improvement in operating temperature range of about −20 to 150° C.
    Type: Grant
    Filed: March 13, 2000
    Date of Patent: September 10, 2002
    Assignee: Energy Conversion Devices, Inc.
    Inventors: Stanford R. Ovshinsky, Srinivasan Venkatesan, Boyko Aladjov, Rosa T. Young, Thomas Hopper
  • Publication number: 20020119351
    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: Application
    Filed: February 28, 2001
    Publication date: August 29, 2002
    Inventors: Stanford R. Ovshinsky, Boyko Aladjov, Srinivasan Venkatesan, Subhash K. Dhar, Thomas Hopper, Kevin Fok