Patents by Inventor Balasubramanian Lakshmanan

Balasubramanian Lakshmanan 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: 10811713
    Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) coating a hydrophobic microporous layer across the substrate; (3) coating a catalyst layer onto the hydrophobic microporous layer in the AA region; (4) coating a first fuel cell membrane ionomer layer onto the catalyst layer in the AA region and onto the hydrophobic microporous layer in the WVT region; (5) optionally applying a membrane support layer to the first fuel cell membrane ionomer layer in the AA region and the WVT region; (6) optionally applying a coating of second fuel cell membrane ionomer layer thereby forming a coated substrate; and (7) assembling the coated substrate to a companion coated substrate.
    Type: Grant
    Filed: January 29, 2018
    Date of Patent: October 20, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Mark F. Mathias, Balasubramanian Lakshmanan, Swaminatha P. Kumaraguru, Scott C. Moose
  • Patent number: 10680266
    Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) simultaneously coating a microporous layer, a catalyst layer, and a first membrane ionomer layer onto the substrate; (3) applying an optional membrane support layer to the first membrane ionomer layer in the AA region and the WVT region; (4) applying an optional second membrane ionomer layer; (5) heating treating a coated substrate; and (6) assembling the coated substrate to a companion coated substrate.
    Type: Grant
    Filed: February 15, 2018
    Date of Patent: June 9, 2020
    Assignee: GM Global Technology Operations LLC
    Inventors: Mark F. Mathias, Balasubramanian Lakshmanan, Swaminatha P. Kumaraguru, Scott C. Moose
  • Patent number: 10547074
    Abstract: A fuel cell system that includes a component for removing anionic contaminants is provided. The fuel system including a fuel cell stack, a fuel gas feed subsystem in communication with fuel cell anodes in the fuel cell stack, an oxygen-containing gas feed subsystem system in communication with fuel cell cathodes in the fuel cell stack, and an anionic scavenging subsystem in communication with the fuel gas feed subsystem and/or the an oxygen-containing gas feed subsystem.
    Type: Grant
    Filed: October 5, 2016
    Date of Patent: January 28, 2020
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Qiang Li, Paul Taichiang Yu, Jingxin Zhang, Balasubramanian Lakshmanan
  • Publication number: 20200028189
    Abstract: A fuel cell assembly includes a fuel cell stack. A vehicle includes a propulsion system and the fuel cell assembly configured to provide power to the propulsion system in at least one mode. The fuel cell assembly also includes an air compressor and an air pump spaced from the air compressor. The air compressor includes an on position in which the air compressor is configured to supply air to the fuel cell stack and an off position in which the air compressor does not supply air to the fuel cell stack. The air compressor also includes a bearing configured to be levitated via air. The air pump is configured to supply air to the fuel cell stack when the air compressor is in the off position and configured to supply air to the bearing when the air compressor is in the on position.
    Type: Application
    Filed: July 18, 2018
    Publication date: January 23, 2020
    Applicant: GM Global Technology Operations LLC
    Inventors: Kelsey M. Rollag, Balasubramanian Lakshmanan
  • Patent number: 10522859
    Abstract: A fuel cell system includes a fuel cell stack and a controller. The fuel cell stack includes a catalyst and a stack voltage. The controller increases efficiency of the fuel cell stack by minimizing or removing an accumulation of oxides on the catalyst during a low-power operating mode of the fuel cell system. The controller executes a method for dynamically controlling the stack voltage during a detected low-power operating mode. The method includes commanding low-voltage/high-power pulses to the fuel cell stack via the controller at a magnitude and frequency sufficient for minimizing or removing the oxides. The system may include a direct current-direct current (DC-DC) boost converter, with the controller programmed to command the power pulses from the DC-DC boost converter. Or, the controller may be configured to command the power pulses by controlling a feed rate of the oxygen and/or the hydrogen.
    Type: Grant
    Filed: May 1, 2017
    Date of Patent: December 31, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Srikanth Arisetty, Andrew J. Maslyn, Balasubramanian Lakshmanan, Robert J. Moses
  • Patent number: 10522855
    Abstract: A method for creating an oxygen depleted gas in a fuel cell system, including operating a fuel cell stack at a desired cathode stoichiometry at fuel cell system shutdown to displace a cathode exhaust gas with an oxygen depleted gas. The method further includes closing a cathode flow valve and turning off a compressor to stop the flow of cathode air.
    Type: Grant
    Filed: October 19, 2015
    Date of Patent: December 31, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Thomas W. Tighe, Steven G. Goebel, Gary M. Robb, Abdullah B. Alp, Balasubramanian Lakshmanan, Joseph N. Lovria
  • Patent number: 10446862
    Abstract: Disclosed are fuel cell architectures, thermal sub-systems, and control logic for regulating fuel cell stack temperature. A method is disclosed for regulating the temperature of a fuel cell stack. The method includes determining a pre-start temperature of the fuel cell stack, and determining, for this pre-start temperature, a target heating rate to heat the stack to a calibrated minimum operating temperature. The method then determines a hydrogen bleed percentage for the target heating rate, and executes a stack heating operation including activating the fuel cell stack and commanding a fluid control device to direct hydrogen to the cathode side at the hydrogen bleed percentage to generate waste heat. After a calibrated period of time, the method determines if an operating temperature of the stack exceeds the calibrated minimum stack operating temperature. Responsive to the operating temperature being at or above the minimum operating temperature, the stack heating operation is terminated.
    Type: Grant
    Filed: May 8, 2017
    Date of Patent: October 15, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Srikanth Arisetty, Aaron R. Rogahn, Balasubramanian Lakshmanan
  • Patent number: 10439241
    Abstract: A method for reducing fuel cell voltage loss in a fuel cell that includes an anode catalyst layer including an anode catalyst and a cathode catalyst layer including a cathode catalyst with a proton exchange layer interposed between the anode catalyst layer and the cathode catalyst layer. The method includes a step of initiating shutdown of the fuel cell. Carbon monoxide or carbon monoxide-like species contaminating the anode catalyst is oxidized during shutdown such that carbon monoxide or carbon monoxide-like species is removed from the anode catalyst.
    Type: Grant
    Filed: October 28, 2015
    Date of Patent: October 8, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jingxin Zhang, Paul Taichiang Yu, Balasubramanian Lakshmanan
  • Publication number: 20190252705
    Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) simultaneously coating a microporous layer, a catalyst layer, and a first membrane ionomer layer onto the substrate; (3) applying an optional membrane support layer to the first membrane ionomer layer in the AA region and the WVT region; (4) applying an optional second membrane ionomer layer; (5) heating treating a coated substrate; and (6) assembling the coated substrate to a companion coated substrate.
    Type: Application
    Filed: February 15, 2018
    Publication date: August 15, 2019
    Inventors: Mark F. Mathias, Balasubramanian Lakshmanan, Swaminatha P. Kumaraguru, Scott C. Moose
  • Publication number: 20190237787
    Abstract: The present disclosure provides a method for manufacturing an integrated MEA, the method includes the following steps: (1) providing a substrate having an AA region and a WVT region; (2) coating a hydrophobic microporous layer across the substrate; (3) coating a catalyst layer onto the hydrophobic microporous layer in the AA region; (4) coating a first fuel cell membrane ionomer layer onto the catalyst layer in the AA region and onto the hydrophobic microporous layer in the WVT region; (5) optionally applying a membrane support layer to the first fuel cell membrane ionomer layer in the AA region and the WVT region; (6) optionally applying a coating of second fuel cell membrane ionomer layer thereby forming a coated substrate; and (7) assembling the coated substrate to a companion coated substrate.
    Type: Application
    Filed: January 29, 2018
    Publication date: August 1, 2019
    Inventors: Mark F. Mathias, Balasubramanian Lakshmanan, Swaminatha P. Kumaraguru, Scott C. Moose
  • Patent number: 10329150
    Abstract: A system and method for determining the purity level of hydrogen gas fuel provided to an anode side of a fuel cell stack, and then modifying models and algorithms used by the system based on the purity level. The method includes determining whether predetermined criteria have been met that are necessary to obtain an accurate hydrogen gas fuel purity level, and if so, comparing a measured voltage or current of the fuel cell stack to a modeled voltage or current of the fuel cell stack. If the comparison between the measured voltage or current and the modeled voltage or current is greater than a predetermined threshold, then the method adapts a hydrogen gas concentration value to a lower purity level to be used by downstream models.
    Type: Grant
    Filed: June 29, 2017
    Date of Patent: June 25, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: William J. Dwyer, Jeffrey J. Gagliardo, Pamela M. Vecasey, Balasubramanian Lakshmanan
  • Patent number: 10276878
    Abstract: A fuel cell flow field plate includes an aluminum substrate plate having a first side and a second side wherein the first side of the aluminum substrate plate defines a plurality of channels for transporting a first fuel cell reactant gas. The flow field plate also includes a first metal interlayer deposited on the first side of the aluminum substrate plate, a second metal interlayer deposited on the second side of the aluminum substrate plate, a first amorphous carbon layer deposited on the first metal interlayer, and a second amorphous carbon layer deposited on the second metal interlayer. The first amorphous carbon layer and second amorphous carbon layer each independently have a density greater than or equal to 1.2 g/cc.
    Type: Grant
    Filed: July 8, 2016
    Date of Patent: April 30, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Smuruthi Kamepalli, Balasubramanian Lakshmanan, Elizabeth Dicocco
  • Publication number: 20190123364
    Abstract: The present disclosure provides an integrated fuel cell having a water vapor transfer region wherein the integrated fuel cell includes a first bipolar plate, a second bipolar plate, and a membrane electrode assembly (MEA) disposed between the first and second bipolar plates. The membrane electrode assembly further includes a water vapor transfer portion and at least one active area portion configured to generate electricity and provide a water byproduct upon facilitating a reaction involving an input stream containing hydrogen and an input stream containing oxygen.
    Type: Application
    Filed: October 24, 2017
    Publication date: April 25, 2019
    Inventors: Mark F Mathias, Balasubramanian Lakshmanan, Wenbin Gu
  • Patent number: 10236517
    Abstract: A method for manufacturing a coated metal substrate includes the steps of: (1) inserting a substrate with a chromium(III) oxide layer inside a CVD chamber; (2) heating the substrate to a temperature which falls in the range of 400 to 500 degrees Celsius; (3) transporting gaseous nitrogen (N2) and tantalum chloride (TaCl5) into the CVD chamber for at least two cycles; (4) ceasing the transportation of tantalum chloride (TaCl5) while nitrogen continues to flow from the inlet to the outlet; (5) reacting the tantalum chloride and the chromium(III) oxide and creating by-products; and (6) vacuuming the by-product matter from the CVD chamber via the flowing nitrogen gas.
    Type: Grant
    Filed: August 16, 2017
    Date of Patent: March 19, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Smuruthi Kamepalli, Balasubramanian Lakshmanan
  • Publication number: 20190058200
    Abstract: A method for manufacturing a coated metal substrate includes the steps of: (1) inserting a substrate with a chromium(III) oxide layer inside a CVD chamber; (2) heating the substrate to a temperature which falls in the range of 400 to 500 degrees Celsius; (3) transporting gaseous nitrogen (N2) and tantalum chloride (TaCl5) into the CVD chamber for at least two cycles; (4) ceasing the transportation of tantalum chloride (TaCl5) while nitrogen continues to flow from the inlet to the outlet; (5) reacting the tantalum chloride and the chromium(III) oxide and creating by-products; and (6) vacuuming the by-product matter from the CVD chamber via the flowing nitrogen gas.
    Type: Application
    Filed: August 16, 2017
    Publication date: February 21, 2019
    Inventors: Smuruthi Kamepalli, Balasubramanian Lakshmanan
  • Patent number: 10193173
    Abstract: A fuel cell stack hydrogen starvation detection device, a fuel cell system and a method of operating a fuel cell stack to protect it from hydrogen starvation conditions. In one particular form, the fuel cell system includes a stack of fuel cells, a controller and a detection device made up of one or more sensors that can compare a reference signal corresponding to the presence of substantially pure hydrogen to a signal that corresponds to a local hydrogen value within a single fuel cell within the stack or across multiple fuel cells within the stack. In this way, the detection device promptly provides indicia of a hydrogen starvation condition within the cell or stack without the need for conventional cell voltage monitoring. The detected hydrogen starvation condition may be presented as a warning signal to alert a user that such a condition may be present, as well as to the controller for modification of the stack operation.
    Type: Grant
    Filed: July 21, 2015
    Date of Patent: January 29, 2019
    Assignee: GM Global Technology Operations LLC
    Inventors: Jingxin Zhang, Balasubramanian Lakshmanan, Manish Sinha
  • Patent number: 10186723
    Abstract: A method for controlling a pressure drop across the anode side or the cathode side of a fuel cell stack by controlling the intrusion of a cell separator into the flow channels in a feeder region of the stack so as to create a larger pressure volume on a pressure bias side of the stack. The method controls the flow rates of one or both of the cathode and anode reactant gases so as to cause the cell separators in an inlet feeder region and/or an outlet feeder region to move relative to the anode side and the cathode side so as to change a flow volume in the inlet feeder region and/or the outlet feeder region to control the pressure drop.
    Type: Grant
    Filed: March 20, 2017
    Date of Patent: January 22, 2019
    Assignee: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jeffrey J. Gagliardo, Jeremy W. Dabel, Balasubramanian Lakshmanan
  • Publication number: 20190002279
    Abstract: A system and method for determining the purity level of hydrogen gas fuel provided to an anode side of a fuel cell stack, and then modifying models and algorithms used by the system based on the purity level. The method includes determining whether predetermined criteria have been met that are necessary to obtain an accurate hydrogen gas fuel purity level, and if so, comparing a measured voltage or current of the fuel cell stack to a modeled voltage or current of the fuel cell stack. If the comparison between the measured voltage or current and the modeled voltage or current is greater than a predetermined threshold, then the method adapts a hydrogen gas concentration value to a lower purity level to be used by downstream models.
    Type: Application
    Filed: June 29, 2017
    Publication date: January 3, 2019
    Inventors: WILLIAM J. DWYER, JEFFREY J. GAGLIARDO, PAMELA M. VECASEY, BALASUBRAMANIAN LAKSHMANAN
  • Publication number: 20180366738
    Abstract: Systems and methods of the present disclosure include supplying a porous substrate, heating the porous substrate to produce a pre-heated substrate, applying an electrode ink to the pre-heated substrate to produce a coated substrate, and drying the electrode ink of the coated substrate to produce an electrode on the porous substrate. The pre-heated substrate has a temperature greater than 23° C. The applying occurs via a coating mechanism. The electrode ink includes a catalyst and an ionomer dispersed in a solvent. The drying occurs via a drying mechanism.
    Type: Application
    Filed: June 16, 2017
    Publication date: December 20, 2018
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Nagappan Ramaswamy, Ellazar V. Niangar, Balasubramanian Lakshmanan
  • Patent number: 10158128
    Abstract: Disclosed are fuel cell stack break-in procedures, conditioning systems for performing break-in procedures, and motor vehicles with a fuel cell stack conditioned in accordance with disclosed break-in procedures. A break-in method is disclosed for conditioning a membrane assembly of a fuel cell stack. The method includes transmitting humidified hydrogen to the anode of the membrane assembly, and transmitting deionized water to the cathode of the membrane assembly. An electric current and voltage cycle are applied across the fuel cell stack while the fuel cell stack is operated in a hydrogen pumping mode until the fuel cell stack is determined to operate at a predetermined threshold for a fuel cell stack voltage output capability. During hydrogen pumping, the membrane assembly oxidizes the humidified hydrogen, transports protons from the anode to the cathode across the proton conducting membrane, and regenerates the protons in the cathode through a hydrogen evolution reaction.
    Type: Grant
    Filed: March 7, 2017
    Date of Patent: December 18, 2018
    Assignee: GM Global Technology Operations LLC
    Inventors: Jingxin Zhang, Nagappan Ramaswamy, Balasubramanian Lakshmanan, Swaminatha P. Kumaraguru