Patent application number | Description | Published |
20080226967 | BIFURCATION OF FLOW CHANNELS IN BIPOLAR PLATE FLOWFIELDS - A bipolar plate for a fuel cell is provided that includes a flowfield having an active surface with an inlet region and an outlet region. The active surface of the flowfield is in communication with the inlet region and the outlet region and has at least one flow channel formed therein. The at least one flow channel further has a cross-sectional area at the outlet region that is less than a cross-sectional area at the inlet region. In particular embodiments, the at least one flow channel is bifurcated. A fuel cell stack including a fuel cell and the bipolar plate is also provided. | 09-18-2008 |
20080254339 | CONSTANT CHANNEL CROSS-SECTION IN A PEMFC OUTLET - A plate for a fuel cell is disclosed, wherein an inlet aperture is disposed at a first end of the plate and an outlet aperture is disposed at a second end of the plate. The plate includes a first side and a second side. The first side of the plate has a flow field formed therein between the inlet aperture and the outlet aperture, the flow field having a plurality of flow channels formed therein, the plurality of flow channels in communication with a plurality of outlet ports formed in the plate. The second side of the plate has a plurality of drainage channels formed therein adjacent the outlet aperture, the plurality of drainage channels in fluid communication with the outlet ports and the outlet aperture, wherein a cross-sectional area occupied by each of the plurality of flow channels is substantially equal to a cross-sectional area occupied by each of the plurality of drainage channels. | 10-16-2008 |
20090068535 | FUEL CELL BIPOLAR PLATE EXIT FOR IMPROVED FLOW DISTRIBUTION AND FREEZE COMPATIBILITY - A fuel cell assembly is disclosed that utilizes a water transport structure extending from fuel cell plates of the assembly into fuel cell assembly manifolds, wherein the water transport structure facilitates the transport of liquid water from the fuel cell plates thereby minimizing the accumulation of liquid water and ice in the fuel cell stack. | 03-12-2009 |
20090117432 | Water Removal Features for PEMFC Stack Manifolds - A bipolar plate includes angled facets oriented to form V-shaped projections on the plate edge. Liquid leaving the reactant channels is drawn back into the V-shaped grooves of the projections, leaving no liquid to obstruct the channel exit openings. The bipolar plate includes one portion of the bipolar plate offset from another portion of the bipolar plate so as to expose the reactant channels. The liquid is drawn toward the end portions of the reactant channels by capillary forces, while the gas flows can exit near the beginning of the offset portion. A fuel cell stack includes angled facets that are rotated to lie in the plane of the bipolar plate edges. The edges are chamfered so the channel exit openings of the reactant channels are at the tip portions thereof, thus allowing the liquid to flow away from the channel exit openings and the gas to exit freely. | 05-07-2009 |
20090142632 | FUEL CELL STACK FEATURES FOR IMPROVED WATER MANAGEMENT - An electric insulator for a fuel cell stack with a plurality of fuel cell plates is provided. The electric insulator includes an insulation layer having a water management feature adapted to militate against liquid water contacting the fuel cell plates. Fuel cell stacks having the water management feature are also described. | 06-04-2009 |
20090191351 | FUEL CELL BIPOLAR PLATE WITH VARIABLE SURFACE PROPERTIES - One embodiment of the invention includes a first fuel cell component comprising a first face, a first hydrophilic coating overlying at least a first portion of the first face, and a second less hydrophilic coating overlying at least a second portion of the first face. | 07-30-2009 |
20110053011 | PEM FUEL CELL STACK INLET WATER REGULATION SYSTEM - A fuel cell stack assembly is disclosed that includes a porous member disposed within a flow path for a reactant. A fluid collection member is provided within the flow path adjacent to and in fluid communication with the porous member. The porous member and the fluid collection member cooperate to collect liquid water from the reactant flowing in the flow path, wherein the collected liquid water may be drained from the fluid collection member. | 03-03-2011 |
20110143241 | FUEL CELL OPERATIONAL METHODS FOR OXYGEN DEPLETION AT SHUTDOWN - 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. | 06-16-2011 |
20110143243 | FUEL CELL OPERATIONAL METHODS FOR HYDROGEN ADDITION AFTER SHUTDOWN - A method for reducing the probability of an air/hydrogen front in a fuel cell stack is disclosed that includes closing anode valves for an anode side of the fuel cell stack to permit a desired quantity of hydrogen to be left in the anode side upon shutdown and determining a schedule to inject hydrogen during the time the fuel cell stack is shutdown. The pressure on an anode input line is determined and a discrete amount of hydrogen is injected into the anode side of the stack according to the determined schedule by opening anode input line valves based on the determined pressure along the anode input line so as to inject the hydrogen into the anode side of the stack. | 06-16-2011 |
20110207023 | COMPRESSOR SYSTEM WITH A FREEWHEELING EXPANDER - A fuel cell system is disclosed that employs an expander for recovering mechanical energy from a cathode exhaust fluid produced by the fuel cell system to generate torque. The expander is coupled to a shaft of a compressor with a freewheel mechanism, wherein the freewheel mechanism transfers the torque from the expander to the compressor when a rate of rotation of a driveshaft of the expander is greater than the rate of rotation of the shaft of the compressor, and selectively militates against the expander acting as a restrictor to the shaft of the compressor when a rate of rotation of the driveshaft of the expander is substantially equal to or less than a rate of rotation of the shaft of the compressor. | 08-25-2011 |
20120288780 | ACOUSTIC SPEED OF SOUND MEASUREMENT USING BANDPASS FILTERING OF AUTOMOTIVE PRESSURE SENSORS - A fuel cell system that determines the concentration of hydrogen gas in an anode loop. The fuel cell system includes at least one fuel cell, an anode inlet, an anode outlet, an anode loop, a source of hydrogen gas and an injector for injecting the hydrogen gas. First and second pressure sensors are provided in the anode loop and are spaced a known distance from each other. A controller responsive to the output signals from the first and second pressure sensors filters the sensor signals from the first and second pressure sensors and determines the concentration of hydrogen gas in the anode loop based on the time difference between the filtered sensor signal from the first pressure sensor and the filtered sensor signal from the second pressure sensor. | 11-15-2012 |
20130040211 | METHOD TO CORRECT FOR PERMEATION UNCERTAINTIES USING A CONCENTRATION SENSOR - A method for determining a rate of accumulation of nitrogen in an anode side of a fuel cell stack. The method includes determining a concentration of nitrogen in an anode loop and determining a number of moles of nitrogen in the anode loop. The method also includes determining a rate of accumulation of nitrogen in the anode loop and determining a permeability factor of nitrogen through fuel cell membranes in the fuel cell stack using the determined rate of accumulation of nitrogen in the anode loop. | 02-14-2013 |
20130122389 | FUEL CELL BIPOLAR PLATE EXIT FOR IMPROVED FLOW DISTRIBUTION AND FREEZE COMPATIBILITY - A fuel cell assembly is disclosed that utilizes a water transport structure extending from fuel cell plates of the assembly into fuel cell assembly manifolds, wherein the water transport structure facilitates the transport of liquid water from the fuel cell plates thereby minimizing the accumulation of liquid water and ice in the fuel cell stack. | 05-16-2013 |
20140093639 | Fuel Cell Component With Coating Including Nanoparticles - A product comprising a fuel cell component comprising a substrate and a coating overlying the substrate, the coating comprising nanoparticles having sizes ranging from 2 to 100 nanometers. | 04-03-2014 |
20150093673 | PEM FUEL CELL STACK INLET WATER REGULATION SYSTEM - A fuel cell stack assembly is disclosed that includes a porous member disposed within a flow path for a reactant. A fluid collection member is provided within the flow path adjacent to and in fluid communication with the porous member. The porous member and the fluid collection member cooperate to collect liquid water from the reactant flowing in the flow path, wherein the collected liquid water may be drained from the fluid collection member. | 04-02-2015 |