Patents by Inventor Bharat Rawal

Bharat Rawal 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).

  • Patent number: 10679798
    Abstract: An ultracapacitor that contain a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The first current collector and the second current collector each contain a substrate that includes a conductive metal, wherein a plurality of fiber-like whiskers project outwardly from the substrate of the first current collector, the substrate of the second current collector, or both.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: June 9, 2020
    Assignee: AVX Corporation
    Inventors: Jonathan Robert Knopsnyder, Bharat Rawal
  • Patent number: 10658127
    Abstract: An ultracapacitor that contains a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The nonaqueous electrolyte is in ionic contact with the first electrode and the second electrode, wherein the nonaqueous electrolyte contains an ionic liquid that is dissolved in a nonaqueous solvent at a concentration of about 1.0 mole per liter or more. The nonaqueous solvent has a boiling temperature of about 150° C. or more.
    Type: Grant
    Filed: May 18, 2017
    Date of Patent: May 19, 2020
    Assignee: AVX Corporation
    Inventors: Jonathan Robert Knopsnyder, Bharat Rawal
  • Patent number: 10312028
    Abstract: An ultra-thin electrochemical energy storage device is provided which utilizes electrode material with multi-layer current collectors and with an organic electrolyte between the electrodes. Multiple cells may be positioned in a plurality of stacks and all of the cells may be in series, parallel or some combination thereof. The energy storage device can be constructed at less than 0.5 millimeters thick and exhibit very low ESR and higher temperature range capabilities.
    Type: Grant
    Filed: June 25, 2015
    Date of Patent: June 4, 2019
    Assignee: AVX Corporation
    Inventors: Bharat Rawal, Carl L. Eggerding, Bob Knopsnyder
  • Publication number: 20170338061
    Abstract: An ultracapacitor that contains a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The first current collector and the second current collector each contain a substrate that includes a conductive metal, wherein a plurality of fiber-like whiskers project outwardly from the substrate of the first current collector, the substrate of the second current collector, or both.
    Type: Application
    Filed: May 18, 2017
    Publication date: November 23, 2017
    Inventors: Jonathan Robert Knopsnyder, Bharat Rawal
  • Publication number: 20170338059
    Abstract: An ultracapacitor that contains a first electrode, second electrode, separator, nonaqueous electrolyte, and housing is provided. The first electrode comprises a first current collector electrically coupled to a first carbonaceous coating and the second electrode comprises a second current collector electrically coupled to a second carbonaceous coating. The nonaqueous electrolyte is in ionic contact with the first electrode and the second electrode, wherein the nonaqueous electrolyte contains an ionic liquid that is dissolved in a nonaqueous solvent at a concentration of about 1.0 mole per liter or more. The nonaqueous solvent has a boiling temperature of about 150° C. or more.
    Type: Application
    Filed: May 18, 2017
    Publication date: November 23, 2017
    Inventors: Jonathan Robert Knopsnyder, Bharat Rawal
  • Publication number: 20150380175
    Abstract: An ultra-thin electrochemical energy storage device is provided which utilizes electrode material with multi-layer current collectors and with an organic electrolyte between the electrodes. Multiple cells may be positioned in a plurality of stacks and all of the cells may be in series, parallel or some combination thereof. The energy storage device can be constructed at less than 0.5 millimeters thick and exhibit very low ESR and higher temperature range capabilities.
    Type: Application
    Filed: June 25, 2015
    Publication date: December 31, 2015
    Applicant: AVX Corporation
    Inventors: Bharat Rawal, Carl L. Eggerding, Bob Knopsnyder
  • Patent number: 8576544
    Abstract: A capacitor assembly that includes a conductive polymer electrolytic capacitor that is enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas is provided. Without intending to be limited by theory, the present inventors believe that the ceramic housing is capable of limiting the amount of oxygen and moisture supplied to the conductive polymer of the capacitor. In this manner, the conductive polymer is less likely to oxidize in high temperature environments, thus increasing the thermal stability of the capacitor assembly.
    Type: Grant
    Filed: January 9, 2012
    Date of Patent: November 5, 2013
    Assignee: AVX Corporation
    Inventors: Bharat Rawal, Gang Ning, Brady Jones, Zebbie Lynn Sebald, Stanislav Zednicek, Zdenek Sita
  • Patent number: 8385052
    Abstract: A capacitor containing an electrochemical cell that includes ruthenium oxide electrodes and an aqueous electrolyte containing a polyprotic acid (e.g., sulfuric acid) is provided. More specifically, the electrodes each contain a substrate that is coated with a metal oxide film formed from a combination of ruthenium oxide and inorganic oxide particles (e.g., alumina, silica, etc.). Without intending to be limited by theory, it is believed that the inorganic oxide particles may enhance proton transfer (e.g., proton generation) in the aqueous electrolyte to form hydrated inorganic oxide complexes (e.g., [Al(H2O)63+] to [Al2(H2O)8(OH2)]4+). The inorganic oxide thus acts as a catalyst to both absorb and reversibly cleave water into protons and molecular bonded hydroxyl bridges. Because the anions (e.g.
    Type: Grant
    Filed: December 10, 2008
    Date of Patent: February 26, 2013
    Assignee: AVX Corporation
    Inventors: Jessica M. Smith, Lee Shinaberger, Bob Knopsnyder, Gang Ning, Bharat Rawal, Dirk Dreissig
  • Patent number: 8345406
    Abstract: An electric double layer capacitor that contains at least one electrochemical cell is provided. The cell contains electrodes (e.g., two electrodes) that each contain a porous matrix of electrochemically-active particles (e.g., carbon). An aqueous-based electrolyte is disposed in contact with the porous matrix. In accordance with the present invention, the electrolyte is provided with an anionic polymer that serves as binding agent for the electrochemically active particles and thus reduces electrolyte loss, especially at higher temperatures. Because the polymer is anionic in nature, it is generally hydrophilic and thus can retain its binding properties in the presence of water. The anionic nature of the polymer also allows it to remain stable in the presence of a corrosive polyprotic acid, which is employed in the electrolyte to enhance charge density. Thus, as a result of the present invention, a capacitor may be formed that is capable of exhibiting good electrical performance (e.g.
    Type: Grant
    Filed: March 23, 2009
    Date of Patent: January 1, 2013
    Assignee: AVX Corporation
    Inventors: Dirk H. Dreissig, Jonathan R. Knopsnyder, Jessica M. Smith, Lee Shinaberger, Bharat Rawal
  • Patent number: 8279585
    Abstract: A cathode containing a metal substrate that possesses a micro-roughened surface imparted by spark anodization is provided. The surface is formed by contacting the substrate with an electrolytic solution and applying a voltage to form a dielectric sub-oxide layer. The voltage is raised to a sufficiently high level to initiate “sparking” at the surface of the substrate, which is believed to create high local surface temperatures sufficient to etch away the substrate. This results in the formation of a “micro-roughened” surface having a plurality elevated regions. These elevated regions can increase the effective surface area and thus allow for the formation of capacitors with increased cathode capacitance for a given size and/or capacitors with a reduced size for a given capacitance. The elevated regions may also exhibit excellent adhesion to additional electrochemically-active materials and provide enhanced stability in certain liquid electrolytes.
    Type: Grant
    Filed: December 9, 2008
    Date of Patent: October 2, 2012
    Assignee: AVX Corporation
    Inventors: Dirk Dreissig, Bharat Rawal
  • Publication number: 20120113567
    Abstract: A capacitor assembly that includes a conductive polymer electrolytic capacitor that is enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas is provided. Without intending to be limited by theory, the present inventors believe that the ceramic housing is capable of limiting the amount of oxygen and moisture supplied to the conductive polymer of the capacitor. In this manner, the conductive polymer is less likely to oxidize in high temperature environments, thus increasing the thermal stability of the capacitor assembly.
    Type: Application
    Filed: January 9, 2012
    Publication date: May 10, 2012
    Applicant: AVX CORPORATION
    Inventors: Bharat Rawal, Gang Ning, Brady Jones, Zebbie Lynn Sebald, Stanislav Zednicek, Zdenek Sita
  • Patent number: 8094434
    Abstract: A capacitor assembly that includes a conductive polymer electrolytic capacitor that is enclosed and hermetically sealed within a ceramic housing in the presence of an inert gas is provided. Without intending to be limited by theory, the present inventors believe that the ceramic housing is capable of limiting the amount of oxygen and moisture supplied to the conductive polymer of the capacitor. In this manner, the conductive polymer is less likely to oxidize in high temperature environments, thus increasing the thermal stability of the capacitor assembly.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: January 10, 2012
    Assignee: AVX Corporation
    Inventors: Bharat Rawal, Gang Ning, Brady Jones, Zebbie Lynn Sebald, Stanislav Zednicek, Zdenek Sita
  • Patent number: 8023250
    Abstract: A porous substrate for use in a wide variety of applications, such as wet capacitors, is provided. The substrate is formed by subjecting a metal substrate to a voltage while in solution to initiate anodic formation of an oxide film. Contrary to conventional anodization processes, however, the newly created oxide quickly breaks down to once again expose the metal surface to the electrolytic solution. This may be accomplished in a variety of ways, such as by raising the voltage of the solution above a critical level known as the “breakdown voltage”, employing a corrosive acid in the solution that dissolves the oxide, etc. Regardless of the mechanism employed, the nearly simultaneous process of oxide growth/breakdown results in the formation of a structure having pores arranged at substantially regular intervals. The resulting structure is highly porous and can exhibit excellent adhesion to electrochemically-active materials and stability in aqueous electrolytes.
    Type: Grant
    Filed: September 12, 2008
    Date of Patent: September 20, 2011
    Assignee: AVX Corporation
    Inventors: Gang Ning, Zebbie Lynn Sebald, Bharat Rawal
  • Patent number: 7927736
    Abstract: Apparatus and methodology subject matters relate to an improved electrochemical single or multi-cell energy storage device. Also, an outer casing may be provided as a pair of U-shaped shells, a single foil piece, or a tube-shaped structure which encases the internal electro chemical cell stack. The energy storage device and such casing when used advantageously exhibit low internal resistance, low ESR, a high voltage/capacity, and a low contact resistance between the internal stack and the outer casing.
    Type: Grant
    Filed: November 4, 2009
    Date of Patent: April 19, 2011
    Assignee: E.C.R.-Electro Chemical Research Ltd.
    Inventors: Arieh Meitav, Joel Lang, Niles Fleischer, David Lifschitz, Eugene Pecherer, Eli Rosh Chodesh, Joost Manassen, Bharat Rawal
  • Publication number: 20100238606
    Abstract: An electric double layer capacitor that contains at least one electrochemical cell is provided. The cell contains electrodes (e.g., two electrodes) that each contain a porous matrix of electrochemically-active particles (e.g., carbon). An aqueous-based electrolyte is disposed in contact with the porous matrix. In accordance with the present invention, the electrolyte is provided with an anionic polymer that serves as binding agent for the electrochemically active particles and thus reduces electrolyte loss, especially at higher temperatures. Because the polymer is anionic in nature, it is generally hydrophilic and thus can retain its binding properties in the presence of water. The anionic nature of the polymer also allows it to remain stable in the presence of a corrosive polyprotic acid, which is employed in the electrolyte to enhance charge density. Thus, as a result of the present invention, a capacitor may be formed that is capable of exhibiting good electrical performance (e.g.
    Type: Application
    Filed: March 23, 2009
    Publication date: September 23, 2010
    Applicant: AVX Corporation
    Inventors: Dirk H. Dreissig, Jonathan R. Knopsnyder, Jessica M. Smith, Lee Shinaberger, Bharat Rawal
  • Publication number: 20100142124
    Abstract: A cathode containing a metal substrate that possesses a micro-roughened surface imparted by spark anodization is provided. The surface is formed by contacting the substrate with an electrolytic solution and applying a voltage to form a dielectric sub-oxide layer. The voltage is raised to a sufficiently high level to initiate “sparking” at the surface of the substrate, which is believed to create high local surface temperatures sufficient to etch away the substrate. This results in the formation of a “micro-roughened” surface having a plurality elevated regions. These elevated regions can increase the effective surface area and thus allow for the formation of capacitors with increased cathode capacitance for a given size and/or capacitors with a reduced size for a given capacitance. The elevated regions may also exhibit excellent adhesion to additional electrochemically-active materials and provide enhanced stability in certain liquid electrolytes.
    Type: Application
    Filed: December 9, 2008
    Publication date: June 10, 2010
    Applicant: AVX Coporation
    Inventors: Dirk Dreissig, Bharat Rawal
  • Publication number: 20100142123
    Abstract: A capacitor containing an electrochemical cell that includes ruthenium oxide electrodes and an aqueous electrolyte containing a polyprotic acid (e.g., sulfuric acid) is provided. More specifically, the electrodes each contain a substrate that is coated with a metal oxide film formed from a combination of ruthenium oxide and inorganic oxide particles (e.g., alumina, silica, etc.). Without intending to be limited by theory, it is believed that the inorganic oxide particles may enhance proton transfer (e.g., proton generation) in the aqueous electrolyte to form hydrated inorganic oxide complexes (e.g., [Al(H20)63+] to [Al2(H2O)8(OH2)]4+). The inorganic oxide thus acts as a catalyst to both absorb and reversibly cleave water into protons and molecular bonded hydroxyl bridges. Because the anions (e.g.
    Type: Application
    Filed: December 10, 2008
    Publication date: June 10, 2010
    Applicant: AVX CORPORATION
    Inventors: Jessica M. Smith, Lee Shinaberger, Bob Knopsnyder, Gang Ning, Bharat Rawal, Dirk Dreissig
  • Patent number: 7687198
    Abstract: Apparatus and methodology subject matters relate to an improved electrochemical single or multi-cell energy storage device. Also, an outer casing may be provided as a pair of U-shaped shells, a single foil piece, or a tube-shaped structure which encases the internal electrochemical cell stack. The energy storage device and such casing when used advantageously exhibit low internal resistance, low ESR, a high voltage/capacity, and a low contact resistance between the internal stack and the outer casing.
    Type: Grant
    Filed: October 31, 2007
    Date of Patent: March 30, 2010
    Assignee: E.C.R.-Electro Chemical Research Ltd.
    Inventors: Arieh Meitav, Joel Lang, Niles Fleischer, David Lifschitz, Eugene Pecherer, Eli Rosh Chodesh, Joost Manassen, Bharat Rawal
  • Publication number: 20100067174
    Abstract: A porous substrate for use in a wide variety of applications, such as wet capacitors, is provided. The substrate is formed by subjecting a metal substrate to a voltage while in solution to initiate anodic formation of an oxide film. Contrary to conventional anodization processes, however, the newly created oxide quickly breaks down to once again expose the metal surface to the electrolytic solution. This may be accomplished in a variety of ways, such as by raising the voltage of the solution above a critical level known as the “breakdown voltage”, employing a corrosive acid in the solution that dissolves the oxide, etc. Regardless of the mechanism employed, the nearly simultaneous process of oxide growth/breakdown results in the formation of a structure having pores arranged at substantially regular intervals. The resulting structure is highly porous and can exhibit excellent adhesion to electrochemically-active materials and stability in aqueous electrolytes.
    Type: Application
    Filed: September 12, 2008
    Publication date: March 18, 2010
    Applicant: AVX CORPORATION
    Inventors: Gang Ning, Zebbie Lynn Sebald, Bharat Rawal
  • Publication number: 20100047683
    Abstract: Apparatus and methodology subject matters relate to an improved electrochemical single or multi-cell energy storage device. Also, an outer casing may be provided as a pair of U-shaped shells, a single foil piece, or a tube-shaped structure which encases the internal electro chemical cell stack. The energy storage device and such casing when used advantageously exhibit low internal resistance, low ESR, a high voltage/capacity, and a low contact resistance between the internal stack and the outer casing.
    Type: Application
    Filed: November 4, 2009
    Publication date: February 25, 2010
    Applicant: E.C.R.-ELECTRO CHEMICAL RESEARCH, LTD.
    Inventors: Arieh Meitav, Joel Lang, Niles Fleischer, David Lifschitz, Eugene Pecherer, Eli Rosh Chodesh, Joost Manassen, Bharat Rawal