Patents by Inventor Daniel Darga

Daniel Darga 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: 11705557
    Abstract: Various embodiments include fuel cell interconnects having a fuel distribution portion having an inlet opening, a fuel collection portion having an outlet opening, and a primary fuel flow field containing channels, wherein the fuel distribution portion comprises at least one raised feature defining a fuel distribution flow path, and the fuel distribution flow path is not continuous with the channels in the primary fuel flow field. The at least one raised feature may include, for example, a network of ribs and/or dots. Further embodiments include interconnects having a fuel distribution portion with a variable surface depth to provide variable flow restriction and/or a plenum with variable surface depth and raised a raised relief feature on the cathode side, and/or varying flow channel depths and/or rib heights adjacent a fuel hole.
    Type: Grant
    Filed: May 19, 2021
    Date of Patent: July 18, 2023
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Daniel Darga, Cheng-Yu Lin, Vijay Srivatsan
  • Patent number: 11217797
    Abstract: Various embodiments include fuel cell interconnects having a fuel distribution portion having an inlet opening, a fuel collection portion having an outlet opening, and a primary fuel flow field containing channels, wherein the fuel distribution portion comprises at least one raised feature defining a fuel distribution flow path, and the fuel distribution flow path is not continuous with the channels in the primary fuel flow field. The at least one raised feature may include, for example, a network of ribs and/or dots. Further embodiments include interconnects having a fuel distribution portion with a variable surface depth to provide variable flow restriction and/or a plenum with variable surface depth and raised a raised relief feature on the cathode side, and/or varying flow channel depths and/or rib heights adjacent a fuel hole.
    Type: Grant
    Filed: August 28, 2013
    Date of Patent: January 4, 2022
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Daniel Darga, Cheng-Yu Lin, Vijay Srivatsan
  • Publication number: 20210273242
    Abstract: Various embodiments include fuel cell interconnects having a fuel distribution portion having an inlet opening, a fuel collection portion having an outlet opening, and a primary fuel flow field containing channels, wherein the fuel distribution portion comprises at least one raised feature defining a fuel distribution flow path, and the fuel distribution flow path is not continuous with the channels in the primary fuel flow field. The at least one raised feature may include, for example, a network of ribs and/or dots. Further embodiments include interconnects having a fuel distribution portion with a variable surface depth to provide variable flow restriction and/or a plenum with variable surface depth and raised a raised relief feature on the cathode side, and/or varying flow channel depths and/or rib heights adjacent a fuel hole.
    Type: Application
    Filed: May 19, 2021
    Publication date: September 2, 2021
    Inventors: Daniel DARGA, Cheng-Yu LIN, Vijay SRIVATSAN
  • Patent number: 10962492
    Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.
    Type: Grant
    Filed: March 21, 2018
    Date of Patent: March 30, 2021
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Cheng-Yu Lin, Daniel Darga, Michael Groesch, Harald Herchen, Vijay Srivatsan
  • Patent number: 10505206
    Abstract: Various methods of treating a chromium iron interconnect for a solid oxide fuel cell stack and coating the interconnect with a ceramic layer are provided.
    Type: Grant
    Filed: August 31, 2016
    Date of Patent: December 10, 2019
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Tad Armstrong, James Wilson, Harald Herchen, Daniel Darga, Manoj Pillai
  • Publication number: 20180217075
    Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.
    Type: Application
    Filed: March 21, 2018
    Publication date: August 2, 2018
    Inventors: Cheng-Yu Lin, Daniel Darga, Michael Groesch, Harald Herchen, Vijay Srivatsan
  • Patent number: 9993874
    Abstract: A chromium-iron interconnect includes at least one of Fe rich regions in the interconnect and carbon in the interconnect.
    Type: Grant
    Filed: February 24, 2015
    Date of Patent: June 12, 2018
    Assignees: BLOOM ENERGY CORPORATION, STACKPOLE INTERNATIONAL POWDER METAL, ULC
    Inventors: Rohith Shivanath, Brendan Ayre, Tad Armstrong, Michael Gasda, Daniel Darga, Harald Herchen, Chockkalingam Karuppaiah, Brandon Dawson, Ravi Oswal
  • Patent number: 9958406
    Abstract: Methods and systems for measuring and/or estimating a coefficient of thermal expansion (CTE) of a component of a fuel cell system. A CTE measurement technique includes securing a measurement member over a surface of the component via a seal having a melting point, heating the seal above its melting point of the seal, cooling the component, measurement member and seal to a second temperature below the melting point of the seal, and determining the CTE of the component based on the change in the span of the measurement member after cooling. A fuel cell component characterization technique includes measuring an electrical resistivity (ER), conductivity (EC), resistance or conductance of the component, measuring at least one additional property of the component which, together with ER, EC, resistance or conductance, correlates to the CTE of the component, and sorting the component based on the measurements.
    Type: Grant
    Filed: December 3, 2014
    Date of Patent: May 1, 2018
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Cheng-Yu Lin, Daniel Darga, Michael Groesch, Harald Herchen, Vijay Srivatsan
  • Patent number: 9673457
    Abstract: Various embodiments include interconnects and/or end plates having features for reducing stress in a fuel cell stack. In embodiments, an interconnect/end plate may have a window seal area that is recessed relative to the flow field to indirectly reduce stress induced by an interface seal. Other features may include a thicker protective coating and/or larger uncoated area of an end plate, providing a recessed portion on an end plate for an interface seal, and/or recessing the fuel hole region of an interconnect relative to the flow field to reduce stress on the fuel cell. Further embodiments include providing intermittent seal support to minimize asymmetric seal loading and/or a non-circular seal configuration to reduce stress around the fuel hole of a fuel cell.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: June 6, 2017
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Vijay Srivatsan, Michael Groesch, Daniel Darga, Matthias Gottmann, Ram Ramanan, Paturi Balaji Narasimha Prasad, Ramesha Guntanur, Ananda Sundararajan, Sachin Parhar
  • Publication number: 20170054159
    Abstract: Various methods of treating a chromium iron interconnect for a solid oxide fuel cell stack and coating the interconnect with a ceramic layer are provided.
    Type: Application
    Filed: August 31, 2016
    Publication date: February 23, 2017
    Inventors: Tad Armstrong, James Wilson, Harald Herchen, Daniel Darga, Manoj Pillai
  • Patent number: 9570769
    Abstract: Methods for fabricating an interconnect for a fuel cell stack include placing a compressed metal powder interconnect on a porous support, and sintering the interconnect in the presence of a non-oxidizing gas. The method may further include placing the sintered interconnect on a porous support, and oxidizing the interconnect in the presence of flowing air, or placing the sintered interconnect on a dense, non-porous support, and oxidizing the interconnect in the presence of a gas comprising pure oxygen or an oxygen/inert gas mixture that is substantially nitrogen-free.
    Type: Grant
    Filed: October 19, 2015
    Date of Patent: February 14, 2017
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Stephen Couse, Daniel Darga, Harald Herchen, Chockkalingam Karuppaiah
  • Patent number: 9478812
    Abstract: Various embodiments include interconnects for a fuel cell stack that includes a first support frame having a first surface that is configured to be secured to a first surface of a fuel cell. A gas flow separator section is secured to a second surface of the first support frame, opposite the first surface of the first support frame. A second support frame is secured to a second surface of a second fuel cell, opposite the first surface of the first fuel cell. The first and second support frames have a coefficient of thermal expansion (CTE) that substantially matches the CTE of the electrolyte material of the fuel cells, and the gas flow separator section has a CTE that does not substantially match a CTE of an electrolyte material of the fuel cells.
    Type: Grant
    Filed: October 16, 2013
    Date of Patent: October 25, 2016
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Daniel Darga, Avinash Verma, Stephen Couse, Tad Armstrong
  • Patent number: 9468736
    Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes providing a chromium alloy interconnect and providing a nickel mesh in contact with a fuel side of the interconnect. Formation of a chromium oxide layer is reduced or avoided in locations between the nickel mesh and the fuel side of the interconnect. A Cr—Ni alloy or a Cr—Fe—Ni alloy is located at least in the fuel side of the interconnect under the nickel mesh.
    Type: Grant
    Filed: November 17, 2014
    Date of Patent: October 18, 2016
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Daniel Darga, Tad Armstrong, Vijay Srivatsan, Harald Herchen, Cheng-Yu Lin
  • Patent number: 9452475
    Abstract: Various methods of treating a chromium iron interconnect for a solid oxide fuel cell stack and coating the interconnect with a ceramic layer are provided.
    Type: Grant
    Filed: February 28, 2013
    Date of Patent: September 27, 2016
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Tad Armstrong, James Wilson, Harald Herchen, Daniel Darga, Manoj Pillai
  • Patent number: 9368809
    Abstract: Various embodiments include interconnects and/or end plates having features for reducing stress in a fuel cell stack. In embodiments, an interconnect/end plate may have a window seal area that is recessed relative to the flow field to indirectly reduce stress induced by an interface seal. Other features may include a thicker protective coating and/or larger uncoated area of an end plate, providing a recessed portion on an end plate for an interface seal, and/or recessing the fuel hole region of an interconnect relative to the flow field to reduce stress on the fuel cell. Further embodiments include providing intermittent seal support to minimize asymmetric seal loading and/or a non-circular seal configuration to reduce stress around the fuel hole of a fuel cell.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: June 14, 2016
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Paturi Balaji Narasimha Prasad, Ramesha Guntanur, Ananda Sundararajan, Natarajan Ramanan, Daniel Darga
  • Patent number: 9368810
    Abstract: Various embodiments include interconnects and/or end plates having features for reducing stress in a fuel cell stack. In embodiments, an interconnect/end plate may have a window seal area that is recessed relative to the flow field to indirectly reduce stress induced by an interface seal. Other features may include a thicker protective coating and/or larger uncoated area of an end plate, providing a recessed portion on an end plate for an interface seal, and/or recessing the fuel hole region of an interconnect relative to the flow field to reduce stress on the fuel cell. Further embodiments include providing intermittent seal support to minimize asymmetric seal loading and/or a non-circular seal configuration to reduce stress around the fuel hole of a fuel cell.
    Type: Grant
    Filed: November 5, 2013
    Date of Patent: June 14, 2016
    Assignee: Bloom Energy Corporation
    Inventors: Daniel Darga, Vijay Srivatsan, Matthias Gottmann, Ram Ramanan, Paturi Balaji Narasimha Prasad, Ramesha Guntanur
  • Publication number: 20160043415
    Abstract: Methods for fabricating an interconnect for a fuel cell stack include placing a compressed metal powder interconnect on a porous support, and sintering the interconnect in the presence of a non-oxidizing gas. The method may further include placing the sintered interconnect on a porous support, and oxidizing the interconnect in the presence of flowing air, or placing the sintered interconnect on a dense, non-porous support, and oxidizing the interconnect in the presence of a gas comprising pure oxygen or an oxygen/inert gas mixture that is substantially nitrogen-free.
    Type: Application
    Filed: October 19, 2015
    Publication date: February 11, 2016
    Inventors: Stephen Couse, Daniel Darga, Harald Herchen, Chockkalingam Karuppaiah
  • Patent number: 9196909
    Abstract: Methods for fabricating an interconnect for a fuel cell stack include placing a compressed metal powder interconnect on a porous support, and sintering the interconnect in the presence of a non-oxidizing gas. The method may further include placing the sintered interconnect on a porous support, and oxidizing the interconnect in the presence of flowing air, or placing the sintered interconnect on a dense, non-porous support, and oxidizing the interconnect in the presence of a gas comprising pure oxygen or an oxygen/inert gas mixture that is substantially nitrogen-free.
    Type: Grant
    Filed: November 16, 2012
    Date of Patent: November 24, 2015
    Assignee: BLOOM ENERGY CORPORATION
    Inventors: Daniel Darga, Harald Herchen, Chockkalingam Karuppaiah, Ravi Oswal, Shivanand Majagi
  • Publication number: 20150244004
    Abstract: A chromium-iron interconnect includes at least one of Fe rich regions in the interconnect and carbon in the interconnect.
    Type: Application
    Filed: February 24, 2015
    Publication date: August 27, 2015
    Inventors: Rohith SHIVANATH, Brendan AYRE, Tad ARMSTRONG, Michael GASDA, Daniel DARGA, Harald HERCHEN, Chockkalingam KARUPPAIAH, Brandon DAWSON, Ravi OSWAL
  • Publication number: 20150147679
    Abstract: A method of making an interconnect for a solid oxide fuel cell stack includes providing a chromium alloy interconnect and providing a nickel mesh in contact with a fuel side of the interconnect. Formation of a chromium oxide layer is reduced or avoided in locations between the nickel mesh and the fuel side of the interconnect. A Cr—Ni alloy or a Cr—Fe—Ni alloy is located at least in the fuel side of the interconnect under the nickel mesh.
    Type: Application
    Filed: November 17, 2014
    Publication date: May 28, 2015
    Inventors: Daniel DARGA, Tad ARMSTRONG, Vijay SRIVATSAN, Harald HERCHEN, Cheng-Yu LIN