Patent application number | Description | Published |
20080241608 | METHOD OF STARTING UP A FUEL CELL UNDER CONDITIONS IN WHICH WATER MAY FREEZE - A method including starting a fuel cell stack and generating heat in the fuel cell stack to raise the fuel cell stack temperature above 0° C. for each start to eliminate ice in the fuel cell stack before shutdown. | 10-02-2008 |
20080299424 | CARBON MONOXIDE CLEAN-UP IN A PEM FUEL CELL SYSTEM - A fuel processor system contains an autothermal reactor (ATR) that produces a hydrogen-rich first gas stream containing carbon monoxide. Downstream of the ATR, a pressure swing adsorber produces a second hydrogen-rich gas stream containing 5 ppm carbon monoxide or more. Downstream of the PSA, there is a methanation reactor sized to reduce the CO level of the second stream below 5 ppm. A method of operating of proton exchange membrane fuel cell stack involves cooling the methanator output and feeding it into the stack as an anode fuel. | 12-04-2008 |
20090011310 | BIPOLAR PLATE WITH MICROGROOVES FOR IMPROVED WATER TRANSPORT - One embodiment of the invention comprises a fuel cell bipolar plate comprising a substrate comprising a first face, a reactant gas flow field defined in the first face, the reactant gas flow field comprising a plurality of lands and channels, and a plurality of microgrooves formed in the first face. | 01-08-2009 |
20090188872 | WATER TRANSFER DEVICE EMPLOYING A WATER BUFFER TO INCREASE WATER FLUX - A water transfer device can include first and second flow paths separated by a water transfer membrane and a hydrophilic diffusion medium. The hydrophilic diffusion medium is disposed between the water transfer membrane and the first flow path. Water content of a first fluid stream flowing through the first flow path is transferred through the diffusion medium and water transfer membrane and into a second fluid stream flowing through the second flow path. The hydrophilic diffusion medium is operable to absorb liquid water in the first fluid stream and hold the absorbed liquid water in contact with the water transfer membrane. The hydrophilic diffusion medium is also operable to diffuse water vapor in the first fluid stream and transport the water vapor to the water transfer membrane. The water transfer membrane transfers the water in contact therewith to the second fluid stream flowing through second flow path. | 07-30-2009 |
20110039167 | MEMBRANE HUMIDIFIER FOR A FUEL CELL - A membrane humidifier for a fuel cell with a wet side plate having a plurality of flow channels formed therein and a dry side plate having a plurality of flow channels formed therein, the flow channels of the wet side plate adapted to facilitate a flow of a wet gas therethrough and the flow channels of said dry side plate adapted to facilitate a flow of a dry gas therethrough, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized. | 02-17-2011 |
20110239747 | USING AN EFFECTIVENESS APPROACH TO MODEL A FUEL CELL MEMBRANE HUMIDIFICATION DEVICE - A method for determining the water transfer in a water vapor transfer unit of a fuel cell system that employs a model based approach. The method includes determining a capacity ratio of wet streams and dry streams flowing through the water vapor transfer unit, determining the number of mass transfer units of the water vapor transfer unit, estimating a mass transfer effectiveness value given the capacity ratio and the number of mass transfer units for the water vapor transfer unit, and determining the amount of water transferred in the water vapor transfer unit using the mass transfer effectiveness value, the mass flow rates on a dry basis of the dry stream and the wet stream, and the mass flow rates of water of the dry inlet stream and the wet inlet stream. | 10-06-2011 |
20120308904 | FUEL CELL SYSTEM HAVING A FLUID FLOW DISTRIBUTION FEATURE - A fuel cell system includes a water vapor transfer unit and a fluid flow distribution feature, the water vapor transfer unit including a first plate having a plurality of first flow channels for receiving a flow of a first fluid therein, and a second plate having a plurality of second flow channels for receiving a flow of a second fluid therein. The fluid flow distribution feature is configured to control at least one of a volume of flow of the first fluid through the first flow channels and a volume of flow of the second fluid through the second flow channels, wherein at least one of a flow distribution of the first fluid across the first plate and a flow distribution of the second fluid across the second plate is varied. | 12-06-2012 |
20130252116 | Model Based Approach For In-Situ WVTD Degradation Detection In Fuel Cell Vehicles - A method of estimating water vapor transfer unit degradation without having to remove the unit from a fuel cell system to which it cooperates, and a device performing the same. The method includes using a combination of a backward-looking model and a forward-looking model. The first of these models is used to evaluate changes in water vapor transfer effectiveness in the unit, while the second is for determining the water transfer rate of the unit. Together, the models provide a more accurate way to estimate and control relative humidity for both stack inlet and outlet flowpaths, as well as provide an indication of when service or replacement of the water vapor transfer unit may be warranted. | 09-26-2013 |
20140272630 | CATHODE HUMIDIFICATION UNIT ADAPTING DEGREDATION FACTOR - A method and an apparatus to adapt the performance of a cathode humidification unit as a membrane in a fuel cell stack degrades over time. An algorithm compares a sensed humidity profile of the fuel cell stack and model humidity profile of a cathode humidification unit model to calculate a new degradation factor. The cathode humidification unit model uses the degradation factor in the performance of the cathode humidification unit. | 09-18-2014 |