Patent application number | Description | Published |
20080236930 | SOFT START FUEL CELL CONTROL STRATEGY - A method of operating an electrochemical conversion assembly is provided. According to the method, an assembly warm-up operation is executed by increasing the temperature T | 10-02-2008 |
20080286619 | FLEXIBLE BIPOLAR PLATE - The present invention provides for a construction for a bipolar plate for a fuel cell stack that enables the bipolar plate to be a more compliant member in the fuel cell stack. The bipolar plate can be configured to provide varying levels of compliance, as demanded by the design of the fuel cell stack. The bipolar plate can be more compliant than the diffusion media members and the active elements used to form the individual fuel cells. The compliant nature of the individual bipolar plates enables localized dimensional changes that occur within the fuel cell stack to be compensated by a localized deformation of the portions of the bipolar plate within that region. The bipolar plate has an internal coolant flow field where some opposing pairs of lands are spaced apart with a gap therebetween while other opposing pairs of lands are in contact with one another. | 11-20-2008 |
20080299418 | Fuel Cell Stack with Improved End Cell Performance - A fuel cell stack that includes a gas diffusion media for the end cells in the stack that has less of an intrusion into the flow field channels of the end cells that the other cells, so as to increase the flow rate through the flow channels in the end cells relative to the flow rate through the flow channels in the other cells. A different diffusion media can be used in the end cells than the nominal cells, where the end cell diffusion media has less of a channel intrusion as a result of diffusion media characteristics. Also, the same diffusion media could be used in the end cells as the nominal cells, but the end cell diffusion media layers could be thinner than the nominal cell diffusion media layers. Further, a higher amount of pre-compression can be used for the diffusion media in the end cells. | 12-04-2008 |
20080305380 | FUEL CELL COMPRESSION RETENTION SYSTEM USING COMPLIANT STRAPPING - A fuel cell system is provided including a fuel cell stack having a first end and second end. The fuel cell stack includes at least one fuel cell having a membrane-electrode assembly disposed between adjacent gas diffusion layers. The fuel cell system further includes a compression retention system having a plurality of compliant straps adapted to apply a compressive force to the fuel cell stack. The plurality of compliant straps are further adapted to accommodate an expansion of the fuel cell stack during an operation thereof and maintain the compressive force within a desired range. | 12-11-2008 |
20090004513 | METHOD TO MAXIMIZE FUEL CELL STACK SHORTING RESISTANCE - A method of producing a fuel cell stack is disclosed, the method including the steps of compressing the fuel cell stack at a first pressure and compressing the fuel cell stack at a second pressure higher than the first pressure, wherein a shorting resistance of fuel cells in the fuel cell stack is maximized and a durability of the fuel cell stack is maximized. | 01-01-2009 |
20100009240 | STRUCTURAL REINFORCEMENT OF MEMBRANE ELECTRODES - A catalyst ink composition for a fuel cell electrode is provided. The catalyst ink composition includes a plurality of electrically conductive support particles; a catalyst formed from a finely divided precious metal, the catalyst supported by the conductive support particles; an ionomer; at least one solvent; and a reinforcing material configured to bridge and distribute stresses across the electrically conductive support particles of the ink composition upon a drying thereof. An electrode for a fuel cell and a method of fabricating the electrode with the catalyst ink composition are also provided. | 01-14-2010 |
20100159294 | COMBINED SUBGASKET AND MEMBRANE SUPPORT - A combined subgasket and membrane support for a fuel cell is provided. The combined subgasket and membrane support includes a substantially fluid impermeable feed region circumscribing a porous membrane support region. The membrane support region is integrally formed with the feed region. At least one of the membrane support region and the feed region is at least partially formed by a radiation-cured structure. A method for fabricating the subgasket and membrane support for the fuel cell is also provided. | 06-24-2010 |
20100159303 | FUEL CELL FABRICATION USING PHOTOPOLYMER BASED PROCESSES - A fuel cell component is provided, including a substrate disposed adjacent at least one radiation-cured flow field layer. The flow field layer is one of disposed between the substrate and a diffusion medium layer, and disposed on the diffusion medium layer opposite the substrate. The flow field layer has at least one of a plurality of reactant flow channels and a plurality of coolant channels for the fuel cell. The fuel cell component may be assembled as part of a repeating unit for a fuel cell stack. A method for fabricating the fuel cell component and the associated repeating unit for the fuel cell is also provided. | 06-24-2010 |
20100159398 | LAYERED RADIATION-SENSITIVE MATERIALS WITH VARYING SENSITIVITY - A method for fabricating a radiation-cured structure is provided. The method includes the steps of providing a first radiation-sensitive material and applying a second radiation-sensitive material to the first radiation-sensitive material. The first radiation-sensitive material has a first sensitivity. The second radiation-sensitive material has a second sensitivity different from the first sensitivity. At least one mask is placed between at least one radiation source and the first and second radiation-sensitive materials. The mask has a plurality of substantially radiation-transparent apertures. The first and second radiation-sensitive materials are then exposed to a plurality of radiation beams through the radiation-transparent apertures in the mask to form a first construct in the first radiation-sensitive material and a second construct in the second radiation-sensitive material. The first construct and the second construct cooperate to form the radiation-cured structure. | 06-24-2010 |
20100178580 | BIPOLAR PLATE FOR A FUEL CELL STACK - A bipolar plate for a fuel cell is provided that includes a pair of unipolar plates having a separator plate disposed therebetween. One of the unipolar plates is produced from a porous material to minimize cathode transport resistance at high current density. A fuel cell stack including a fuel cell and the bipolar plate is also provided. | 07-15-2010 |
20100291465 | SEPARATOR PLATES FORMED BY PHOTOPOLYMER BASED PROCESSES - A separator plate for a fuel cell is provided, including a substrate having a radiation-cured first flow field layer disposed thereon. A method for fabricating the separator plate is also provided. The method includes the steps of providing a substrate; applying a first radiation-sensitive material to the substrate; placing a first mask between a first radiation source and the first radiation-sensitive material, the first mask having a plurality of substantially radiation-transparent apertures; and exposing the first radiation-sensitive material to a plurality of first radiation beams to form a radiation-cured first flow field layer adjacent the substrate. A fuel cell having the separator plate is also provided. | 11-18-2010 |
20100291466 | DIFFUSION MEDIA FORMED BY PHOTOPOLYMER BASED PROCESSES - A diffusion medium layer for a fuel cell, including an electrically conductive microtruss structure disposed between a pair of electrically conductive grids is provided. At least one of the microtruss structure and the grids is formed from a radiation-sensitive material. A fuel cell having the diffusion medium layer and a method for fabricating the diffusion medium layer is also provided. | 11-18-2010 |
20110039192 | STRUCTURAL REINFORCEMENT OF MEMBRANE ELECTRODES - A catalyst ink composition for a fuel cell electrode is provided. The catalyst ink composition includes a plurality of electrically conductive support particles; a catalyst formed from a finely divided precious metal, the catalyst supported by the conductive support particles; an ionomer; at least one solvent; and a reinforcing material configured to bridge and distribute stresses across the electrically conductive support particles of the ink composition upon a drying thereof. An electrode for a fuel cell and a method of fabricating the electrode with the catalyst ink composition are also provided. | 02-17-2011 |
20110076581 | STACK OPERATION METHOD AIMED AT CELL REVERSAL PREVENTION - A method for preventing a fuel cell voltage potential reversal including determining a relationship between the cell resistance and the current of a fuel cell stack at which a fuel cell voltage potential reversal will occur, operating the fuel cell stack according to a power demand requested, and determining the maximum cell resistance of the fuel cells in the stack. If the maximum cell resistance exceeds a threshold value for the current at which the fuel cell stack is being operated, the operation of the fuel cell stack is restricted to prevent the fuel cell voltage potential from reversing. | 03-31-2011 |
20110090480 | DYNAMIC MASKING METHOD FOR MICRO-TRUSS FOAM FABRICATION - A system for fabricating a radiation-cured structure is provided. The system includes a radiation-sensitive material configured to at least one of initiate, polymerize, crosslink and dissociate with exposure to radiation. At least one radiation source is configured to project a radiation beam toward the radiation-sensitive material. A smart glass device is disposed between the radiation-sensitive material and the at least one radiation source. The smart glass device includes at least one switchable layer selectively operable from an active state to an inactive state. The smart glass device is configured to expose the radiation-sensitive material to a desired exposure pattern when in one of the active state and the inactive state. A method for fabricating the radiation-cured structure is also provided. | 04-21-2011 |
20110091813 | DYNAMIC PROJECTION METHOD FOR MICRO-TRUSS FOAM FABRICATION - A system for fabricating a radiation-cured component is provided. The system includes a radiation-sensitive material configured to at least one of initiate, polymerize, crosslink and dissociate with exposure to radiation, and at least one radiation source configured to project a radiation beam with a vector that does not intersect the radiation-sensitive material. The system further includes a radiation directing device that is selectively positionable to reflect the radiation beam in a desired direction and exposure the radiation-sensitive material to the radiation beam. A method for fabricating the radiation-cured components is also provided. | 04-21-2011 |
20110195337 | MICROTRUSS WATER VAPOR TRANSPORT DEVICE - A fuel cell system includes a water vapor transport device having a wet flow field layer having a coarse microtruss structure disposed between a pair of fine microtruss structures. The coarse and fine microtruss structures of the wet flow field layer are formed from a radiation-sensitive material. A dry flow field layer has a coarse microtruss structure disposed between a pair of fine microtruss structures. The coarse and fine microtruss structures of the dry flow field layer are also formed from a radiation-sensitive material. A membrane is disposed between the wet flow field layer and the dry flow field layer and adapted to permit a transfer of water vapor therethrough from the wet fluid to the dry fluid to form a humidified fluid. | 08-11-2011 |
20110195363 | LAYERED RADIATION-SENSITIVE MATERIALS WITH VARYING SENSITIVITY - A method for fabricating a radiation-cured structure is provided. The method includes the steps of providing a first radiation-sensitive material and a second radiation-sensitive material adjacent the first radiation-sensitive material. The first radiation-sensitive material has a first sensitivity. The second radiation-sensitive material has the first sensitivity and a second sensitivity different from the first sensitivity. At least one mask is placed between at least one radiation source and the first and second radiation-sensitive materials. The mask has a plurality of substantially radiation-transparent apertures. The first and second radiation-sensitive materials are then exposed to a plurality of radiation beams through the radiation-transparent apertures in the mask to form a first construct in the first radiation-sensitive material and a second construct in the second radiation-sensitive material. The first construct and the second construct cooperate to form the radiation-cured structure. | 08-11-2011 |
20110217617 | FUEL CELL COMPRESSION RETENTION SYSTEM USING COMPLIANT STRAPPING - A fuel cell system is provided including a fuel cell stack having a first end and second end. The fuel cell stack includes at least one fuel cell having a membrane-electrode assembly disposed between adjacent gas diffusion layers. The fuel cell system further includes a compression retention system having a plurality of compliant straps adapted to apply a compressive force to the fuel cell stack. The plurality of compliant straps are further adapted to accommodate an expansion of the fuel cell stack during an operation thereof and maintain the compressive force within a desired range. | 09-08-2011 |
20110229823 | FUEL CELL FABRICATION USING PHOTOPOLYMER BASED PROCESSES - A method for fabricating a fuel cell component includes the steps of providing a mask having a plurality of radiation transparent apertures, a radiation-sensitive material having a sensitivity to the plurality of radiation beams, and a flow field layer. The radiation-sensitive material is disposed on the flow field layer. The radiation-sensitive material is then exposed to the plurality of radiation beams through the radiation transparent apertures in the mask to form a diffusion medium layer with a micro-truss structure. | 09-22-2011 |
20120301805 | FUEL CELL FABRICATION USING PHOTOPOLYMER BASED PROCESSES - A fuel cell component is provided, including a substrate disposed adjacent at least one radiation-cured flow field layer. The flow field layer is one of disposed between the substrate and a diffusion medium layer, and disposed on the diffusion medium layer opposite the substrate. The flow field layer has at least one of a plurality of reactant flow channels and a plurality of coolant channels for the fuel cell. The fuel cell component may be assembled as part of a repeating unit for a fuel cell stack. A method for fabricating the fuel cell component and the associated repeating unit for the fuel cell is also provided. | 11-29-2012 |
20130011763 | SEPARATOR PLATES FORMED BY PHOTOPOLYMER BASED PROCESSES - A separator plate for a fuel cell is provided, including a substrate having a radiation-cured first flow field layer disposed thereon. A method for fabricating the separator plate is also provided. The method includes the steps of providing a substrate; applying a first radiation-sensitive material to the substrate; placing a first mask between a first radiation source and the first radiation-sensitive material, the first mask having a plurality of substantially radiation-transparent apertures; and exposing the first radiation-sensitive material to a plurality of first radiation beams to form a radiation-cured first flow field layer adjacent the substrate. A fuel cell having the separator plate is also provided. | 01-10-2013 |
20130033689 | DYNAMIC MASKING METHOD FOR MICRO-TRUSS FOAM FABRICATION - A system for fabricating a radiation-cured structure is provided. The system includes a radiation-sensitive material configured to at least one of initiate, polymerize, crosslink and dissociate with exposure to radiation. At least one radiation source is configured to project a radiation beam toward the radiation-sensitive material. A smart glass device is disposed between the radiation-sensitive material and the at least one radiation source. The smart glass device includes at least one switchable layer selectively operable from an active state to an inactive state. The smart glass device is configured to expose the radiation-sensitive material to a desired exposure pattern when in one of the active state and the inactive state. A method for fabricating the radiation-cured structure is also provided. | 02-07-2013 |
20130135599 | DYNAMIC PROJECTION METHOD FOR MICRO-TRUSS FOAM FABRICATION - A system for fabricating a radiation-cured component is provided. The system includes a radiation-sensitive material configured to at least one of initiate, polymerize, crosslink and dissociate with exposure to radiation, and at least one radiation source configured to project a radiation beam with a vector that does not intersect the radiation-sensitive material. The system further includes a radiation directing device that is selectively positionable to reflect the radiation beam in a desired direction and exposure the radiation-sensitive material to the radiation beam. A method for fabricating the radiation-cured components is also provided. | 05-30-2013 |
20130202989 | COMBINED SUBGASKET AND MEMBRANE SUPPORT - A combined subgasket and membrane support for a fuel cell is provided. The combined subgasket and membrane support includes a substantially fluid impermeable feed region circumscribing a porous membrane support region. The membrane support region is integrally formed with the feed region. At least one of the membrane support region and the feed region is at least partially formed by a radiation-cured structure. A method for fabricating the subgasket and membrane support for the fuel cell is also provided. | 08-08-2013 |
20140051004 | FUEL CELL STACK WITH IMPROVED END CELL PERFORMANCE PROVIDED BY HIGHER MODULUS OF ELASTICITY - A fuel cell stack that includes a gas diffusion media for the end cells in the stack that has less of an intrusion into the flow field channels of the end cells that the other cells, so as to increase the flow rate through the flow channels in the end cells relative to the flow rate through the flow channels in the other cells. A different diffusion media can be used in the end cells than the nominal cells, where the end cell diffusion media has less of a channel intrusion as a result of diffusion media characteristics. Also, the same diffusion media could be used in the end cells as the nominal cells, but the end cell diffusion media layers could be thinner than the nominal cell diffusion media layers. Further, a higher amount of pre-compression can be used for the diffusion media in the end cells. | 02-20-2014 |
20140051005 | FUEL CELL STACK WITH IMPROVED END CELL PERFORMANCE THROUGH A DIFFUSION MEDIA HAVING LOWER COMPRESSIBILITY - A fuel cell stack that includes a gas diffusion media for the end cells in the stack that has less of an intrusion into the flow field channels of the end cells that the other cells, so as to increase the flow rate through the flow channels in the end cells relative to the flow rate through the flow channels in the other cells. A different diffusion media can be used in the end cells than the nominal cells, where the end cell diffusion media has less of a channel intrusion as a result of diffusion media characteristics. Also, the same diffusion media could be used in the end cells as the nominal cells, but the end cell diffusion media layers could be thinner than the nominal cell diffusion media layers. Further, a higher amount of pre-compression can be used for the diffusion media in the end cells. | 02-20-2014 |