Patents by Inventor Chowdary R. Koripella
Chowdary R. Koripella 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).
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Patent number: 7776386Abstract: A method is provided for fabricating an integrated micro fuel cell that derives power from a three-dimensional fuel/oxidant interchange having increased surface area and that is positioned on a second substrate that may be either porous or flexible with gas access holes, thereby avoiding precise alignment requirements of the openings providing fuel thereto. The method comprises forming on a first substrate, a plurality of pedestals including an anode and a cathode each comprising a porous metal; positioning an electrolyte between the anode and the cathode; and forming first metal contacts on the anode and cathode. The first substrate is removed and a second substrate is positioned against the fuel cell wherein the first metal contacts are selectively positioned to make electrical contact with second metal contacts on the second substrate.Type: GrantFiled: January 31, 2007Date of Patent: August 17, 2010Assignee: Motorola, Inc.Inventors: Chowdary R. Koripella, Kurt W. Eisenbeiser, Ramkumar Krishnan
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Publication number: 20080178461Abstract: A method is provided for fabricating an integrated micro fuel cell (50) that derives power from a three-dimensional fuel/oxidant interchange having increased surface area and that is positioned on a second substrate (60) that may be either porous or flexible with gas access holes, thereby avoiding precise alignment requirements of the openings providing fuel thereto. The method comprises forming a fuel cell (51) on a second substrate (12), wherein forming the fuel cell (51) comprises forming, on the substrate (12), a plurality of pedestals (48) including an anode (47) and a cathode (49) each comprising a porous metal (34); positioning an electrolyte (46) between the anode (47) and the cathode (49); and forming first metal contacts (52, 54) on the anode (47) and cathode (49). The fuel cell (51) is then removed from the rigid substrate (12).Type: ApplicationFiled: January 31, 2007Publication date: July 31, 2008Applicant: MOTOROLA, INC.Inventors: Chowdary R. Koripella, Kurt W. Eisenbeiser, Ramkumar Krishnan
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Publication number: 20080118815Abstract: A method is provided for fabricating a fuel cell wherein corrosion of metal diffusion layers or catalysts supports is avoided. The method comprises forming first and second electrical conductors (22, 42) accessible at a surface of a substrate (12). The substrate (12) is etched to provide a channel (34, 36), and a multi-metal layer (82) is deposited on the surface of the substrate (12). At least one metal is etched from the multi-metal layer (82) forming a porous metal layer therefrom. A portion of the porous metal layer is etched resulting in an anode portion (89) aligned with the channel (34, 36) and coupled to the first electrical conductor (22), and a cathode portion (90) coupled to the second electrical conductor (42) and separated from the anode portion by a cavity (91). A first bi-continuous material (97) is formed over the porous metal layer (82) within at least one of the anode (89) and oxidant (90) portions.Type: ApplicationFiled: November 20, 2006Publication date: May 22, 2008Inventors: John J. D'Urso, Chowdary R. Koripella
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Publication number: 20080061027Abstract: A method is provided for fabricating a fuel cell that requires only front side alignment techniques to fabricate gas access holes. The method comprises etching the front side of a substrate (12) to provide a channel (24, 26), and forming a pedestal (54, 88) on the front side of the substrate, wherein the pedestal (54, 88) comprises an anode side (56, 89) defining a fuel region (68, 102) aligned with the channel (24, 26). An electrolyte (46, 96) is positioned between the anode side (56, 89) and a cathode side (58, 90), and the fuel region (68, 102) is capped with an insulator (66, 98). A portion of the substrate (12) is removed from a back side to expose the channel (24, 26).Type: ApplicationFiled: September 12, 2006Publication date: March 13, 2008Inventors: Pawitter S. Mangat, John J. D'Urso, Chowdary R. Koripella, Ramkumar Krishnan
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Patent number: 7335432Abstract: A ceramic fuel processor (10) including a solid oxide fuel cell (32) provides a high power output while maintaining a small size and minimizing heating issues. A fuel reformer (14) comprising a reaction zone (18) including a reforming catalyst. A heat source (28) is thermally coupled to the reaction zone for providing heat thereto. An inlet channel (20) conducts liquid fuel to the reaction zone, and an outlet channel (22) conducts hydrogen enriched gas from the reaction zone to the solid oxide fuel cell.Type: GrantFiled: April 30, 2004Date of Patent: February 26, 2008Assignee: Motorola, Inc.Inventor: Chowdary R. Koripella
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Publication number: 20080003485Abstract: A method is provided for patterning a solid proton conducting electrolyte (22, 60) for a micro fuel cell. The method comprises patterning a first side (30, 63) of a solid proton conducting electrolyte (22, 60) to increase the surface area, coating the patterned first side (22, 60) with an electrocatalyst (33, 66), providing a first electrical conductor (20) to the first side (22, 60), and providing a second electrical conductor (15, 16) to a second side (19) of the solid proton conducting electrolyte (22, 60) opposed to the first side (22, 60).Type: ApplicationFiled: June 30, 2006Publication date: January 3, 2008Inventors: Ramkumar Krishnan, William J. Dauksher, Chowdary R. Koripella
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Patent number: 7204156Abstract: An apparatus (10) is provided for determining the flow rate of a gas. The apparatus comprises a housing (12) forming a vaporization chamber (14) for converting a fluid into a gas vapor when subjected to heat (22). An oscillation flow meter is formed within the housing (12), thereby being integrated with the vaporization chamber, for receiving the gas vapor and providing a frequency signal (60) indicative of the rate of flow of the gas vapor.Type: GrantFiled: July 29, 2005Date of Patent: April 17, 2007Assignee: Motorola, Inc.Inventors: Stephen Samms, Chowdary R. Koripella
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Publication number: 20040228211Abstract: An exemplary system and method for providing substantially uniform mixing of fluid reactants, wherein the flow velocities and/or device dimensions generally correspond to Reynolds numbers less than unity, is disclosed as comprising inter alia: a first fluid inlet (210); a second fluid inlet (220); and a fluid transport channel (240) having a plurality of features (250) corresponding to relatively discontinuous or otherwise abrupt shifts in the fluid transportation gradient. Disclosed features and specifications may be variously controlled, adapted or otherwise optionally modified to improve mixing operation in any diffusion limited application. Exemplary embodiments of the present invention representatively provide for efficient mixing of fluid phases at relatively low Reynolds numbers and may be readily integrated with existing micro-scale technologies for the improvement of device package form factors, weights and other manufacturing and/or device performance metrics.Type: ApplicationFiled: May 13, 2003Publication date: November 18, 2004Inventors: Chowdary R. Koripella, Rajnish G. Changrani, Stephen R. Samms
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Patent number: 6696189Abstract: A fuel cell system and method of forming the fuel cell system including a base portion, formed of a singular body, and having a major surface. At least one fuel cell membrane electrode assembly is formed on the major surface of the base portion. A fluid supply channel including a mixing chamber is defined in the base portion and communicating with the fuel cell membrane electrode assembly for supplying a fuel-bearing fluid to the membrane electrode assembly. A methanol concentration sensor is positioned to communicate with the fuel cell membrane electrode assembly and the fuel-supply channel for regulating the mixture of fuel to the electrode assembly. An exhaust channel including a water recovery and recirculation system is defined in the base portion and communicating with the membrane electrode assembly.Type: GrantFiled: December 15, 2000Date of Patent: February 24, 2004Assignee: Motorola, Inc.Inventors: Joseph W. Bostaph, Chowdary R. Koripella, Allison M. Fisher
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Patent number: 6586885Abstract: A microhollow cathode discharge (MHCD) cavity and microfluidic channel are combined for interrogation of samples. The apparatus includes a dielectric body and layers of conductive material defining a MHCD cavity containing an environment for carrying a gas discharge within the MHCD cavity. The gas discharge generates gas based electromagnetic waves. Electrical connections apply a cathode discharge potential to the layers of conductive material. A microfluidic channel is integrated on the substrate, and a path extends from the MHCD cavity laterally through a portion of the microfluidic channel. A detector, which may be integrated on the common substrate, is positioned to receive electromagnetic waves from the path and electronic circuitry is coupled to the detector for acquiring and processing data.Type: GrantFiled: August 20, 2001Date of Patent: July 1, 2003Assignee: Motorola, Inc.Inventors: Bernard F. Coll, Frederic Zenhausern, Jeremy W. Burdon, Chowdary R. Koripella
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Publication number: 20030034740Abstract: A microhollow cathode discharge (MHCD) cavity and microfluidic channel are combined for interrogation of samples. The apparatus includes a dielectric body and layers of conductive material defining a MHCD cavity containing an environment for carrying a gas discharge within the MHCD cavity. The gas discharge generates gas based electromagnetic waves. Electrical connections apply a cathode discharge potential to the layers of conductive material. A microfluidic channel is integrated on the substrate, and a path extends from the MHCD cavity laterally through a portion of the microfluidic channel. A detector, which may be integrated on the common substrate, is positioned to receive electromagnetic waves from the path and electronic circuitry is coupled to the detector for acquiring and processing data.Type: ApplicationFiled: August 20, 2001Publication date: February 20, 2003Applicant: Motorola, Inc.Inventors: Bernard F. Coll, Frederic Zenhausern, Jeremy W. Burdon, Chowdary R. Koripella
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Patent number: 6497975Abstract: A fuel cell device and method of forming the fuel cell device including a base portion, formed of a singular body, and having a major surface. At least one fuel cell membrane electrode assembly is formed on the major surface of the base portion. A fluid supply channel including a mixing chamber is defined in the base portion and communicating with the fuel cell membrane electrode assembly for supplying a fuel-bearing fluid to the membrane electrode assembly. An exhaust channel is defined in the base portion and communicating with the membrane electrode. A multi-dimensional fuel flow field is defined in the multi-layer base portion and in communication with the fluid supply channel, the membrane electrode assembly and the exhaust channel.Type: GrantFiled: December 15, 2000Date of Patent: December 24, 2002Assignee: Motorola, Inc.Inventors: Joseph W. Bostaph, Chowdary R. Koripella, Allison M. Fisher, Jay K. Neutzler
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Publication number: 20020076589Abstract: A fuel cell system and method of forming the fuel cell system including a base portion, formed of a singular body, and having a major surface. At least one fuel cell membrane electrode assembly is formed on the major surface of the base portion. A fluid supply channel including a mixing chamber is defined in the base portion and communicating with the fuel cell membrane electrode assembly for supplying a fuel-bearing fluid to the membrane electrode assembly. A methanol concentration sensor is positioned to communicate with the fuel cell membrane electrode assembly and the fuel-supply channel for regulating the mixture of fuel to the electrode assembly. An exhaust channel including a water recovery and recirculation system is defined in the base portion and communicating with the membrane electrode assembly.Type: ApplicationFiled: December 15, 2000Publication date: June 20, 2002Applicant: Motorola, Inc.Inventors: Joseph W. Bostaph, Chowdary R. Koripella, Allison M. Fisher
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Publication number: 20020076598Abstract: A fuel cell device and method of forming the fuel cell device including a base portion, formed of a singular body, and having a major surface. At least one fuel cell membrane electrode assembly formed on the major surface of the base portion. A fluid supply channel including a mixing chamber is defined in the base portion and communicating with the fuel cell membrane electrode assembly for supplying a fuel-bearing fluid to the membrane electrode assembly. An exhaust channel is defined in the base portion and communicating with the membrane electrode. A multi-dimensional fuel flow field is defined in the multi-layer base portion and in communication with the fluid supply channel, the membrane electrode assembly and the exhaust channel. The membrane electrode assembly and the cooperating fluid supply channel, multi-dimensional fuel flow field, and cooperating exhaust channel forming a single fuel cell assembly.Type: ApplicationFiled: December 15, 2000Publication date: June 20, 2002Applicant: Motorola, Inc.Inventors: Joseph W. Bostaph, Chowdary R. Koripella, Allison M. Fisher, Jay K. Neutzler
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Patent number: 5989398Abstract: A calorimetric hydrocarbon gas sensor (10) includes an electrochemical oxygen pump (18), a sensing element (12), and a multi-layered substrate (26) separating the sensing element (12) from the electrochemical oxygen pump (18). The multi-layered substrate (26) includes a plurality of overlying insulating layers, in which at least one intermediate layer (60) supports a first primary heater (58), and in which another intermediate layer (52) supports a temperature compensation heaters (50a, 50b). The primary heater (58) functions to maintain the calorimetric hydrocarbon gas sensor (10) at a constant, elevated temperature, while the active compensation heater (50a) functions to maintain substantially equal temperatures as determined by the thermometers (46a, 46b) located on an intermediate layer (48) overlying the compensation heaters (50a, 50b).Type: GrantFiled: November 14, 1997Date of Patent: November 23, 1999Assignee: Motorola, Inc.Inventors: Daniel A. Young, Adam Moya, Chowdary R. Koripella, Jeff Naber, Neil Adams, Craig Markyvech, Adam Miller
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Patent number: 5795545Abstract: A multilayered ceramic integrated sensor 200 for monitoring auto exhaust gases is capable of existing in the relatively harsh environments of the exhaust stream of an internal combustion engine. The integrated sensor 200 may include discrete devices such as an oxygen sensor 104, a hydrogen sensor 206, an NO.sub.x sensor 208, and a carbon monoxide sensor 210. The device 200 may further include a temperature sensor 202 as well as total combustion calorimetric sensor 102. The multilayered ceramic integrated sensor may be fabricated from a plurality of layers of ceramic material disposed in stacked relationship with respect to one another.Type: GrantFiled: May 20, 1996Date of Patent: August 18, 1998Assignee: Motorola Inc.Inventors: Chowdary R. Koripella, Adam D. Moya, David Wilcox, Sr.