Abstract: Fuel cell systems and associated methods of operation are provided whereby application of a fuel cell is coordinated with a fuel processor and a hydrogen separator.

Abstract: The invention provides apparatuses and associated methods of manufacture for fuel cell systems designed for modular application. As an example, a fuel cell system is provided that includes an enclosure housing a fuel cell stack, a power conditioning circuit, and a control circuit. The power conditioning circuit has a first input connector electrically coupled to the fuel cell stack. The power conditioning circuit is adapted to convert a direct current flow from the fuel cell stack to a conditioned alternating current flow having a predetermined voltage (e.g., 120 volts). The conditioned current flow is provided to an outlet connector of the power conditioning circuit located along a first portion of the enclosure. The power conditioning circuit further includes a second input connector located along a second portion of the enclosure. The second input connector is adapted to receive an external current flow.

Abstract: The invention provides a reactant delivery system for a dead-headed PEM fuel cell system, comprising a fuel cell, a fuel supply, a purge valve, an inlet orifice, an outlet orifice, and a controller. A first fuel flow circuit is provided, wherein fuel is flowed from the fuel supply to the inlet orifice, through the fuel cell from the inlet orifice, and through the outlet orifice from the fuel cell to the purge valve. A second fuel flow circuit is also provided, wherein fuel is flowed from the fuel supply to the outlet orifice, through the fuel cell from the outlet orifice, and through the inlet orifice from the fuel cell to the purge valve. A valve means is coupled to the controller and adapted to transfer fuel flow between the first flow circuit and the second flow circuit.

Abstract: The invention provides a fuel cell system, including a fuel cell having an anode chamber and a cathode chamber, wherein the anode chamber is in fluid communication with a hydrogen reservoir, and wherein the cathode chamber has an inlet and an outlet. The cathode chamber comprises non-intersecting flow channels, and the non-intersecting flow channels provide fluid communication between the cathode inlet and outlet. The fuel cell has a first connection to an electrical load, wherein the first connection comprises a first diode adapted to prevent current flow to the fuel cell. A blower is in fluid communication with the cathode inlet. The blower has an electronic connection to a controller, and the blower is adapted to vary a flow of oxygen through the cathode chamber according to a control signal received from the controller.

Abstract: A cogeneration fuel cell system and associated methods of operation are provided that accommodate a demand for heat as well as a demand for electric power. The system is operated among various modes to balance heat and power demand signals. In general, a fuel cell system is coupled to a power sink and a heat sink, and a controller is adapted to respond to data signals from the power sink and the heat sink. As examples, such data signals from the heat sink may include a temperature indication or a heat demand signal (such as from a thermostat), and such data signals from the power sink may include a voltage or current measurement, an electrical power demand signal, or an electrical load.

Abstract: The invention provides a fuel cell system utilizing a shift reaction catalyst disposed within the fuel cell to reduce carbon monoxide present in the fuel stream.

Abstract: The invention generally relates to controlling the temperature and relative humidity of an incoming fuel cell reactant stream. In one aspect, a fuel cell system is provided that includes a fuel cell having an anode inlet adapted to receive a flow of anode gas from an anode inlet conduit, and a cathode inlet adapted to receive a flow of cathode gas from a cathode inlet conduit. A first heat exchange surface is adapted to contact the flow of anode gas within the anode inlet conduit, and a second heat exchange surface adapted to contact the flow of cathode gas within the cathode inlet conduit. A coolant system is adapted to circulate a coolant through a coolant conduit. The coolant system is adapted to transfer heat from each of the first and second heat exchange surfaces to the coolant.

Abstract: The fuel processor system of the invention generates hydrogen from a hydrocarbon compound or from mixtures of hydrocarbon compounds for generating electric energy and heat by way of a combustion path, along which the generated hydrogen is passed for combustion. Included in the combustion path is at least one fuel cell for generating electric energy. The system further includes a first heat exchanger and a second heat exchanger, which, on the one hand, are series included in the combustion path downstream of the fuel cell. The first heat exchanger exchanges heat between the combustion path and a first heating circuit which includes the fuel cell. The second heat exchanger exchanges heat between the combustion path and a second heating circuit which includes the fuel processor. The generated hydrogen undergoes combustion where the fuel cell assists in generating electric energy and, optionally, the fuel processor assists in generating heat.

Abstract: The invention provides integrated fuel cell systems and associated operating methods wherein oxidant flow is controlled in response to an oxygen sensor in an exhaust stream of a fuel cell exhaust gas oxidizer, and fuel flow is controlled in response to a temperature measurement associated with the oxidizer.

Abstract: A composition is provided that can be used, for example, in a fuel processor for a fuel cell system. The composition includes a first material such as a catalyst, and a second material such as a desiccant. The second material is capable of sorbing and desorbing a heat transfer material such as water, and is present in an amount sufficient to sorb an amount of the heat transfer material sufficient to remove a portion of the heat generated when the first material undergoes an exothermic reaction.

Abstract: A fuel cell electrode includes a plate having a front surface and a back surface and also having a plurality of gas delivery holes and a plurality of gas exhaust holes formed through the plate. The front surface of the plate has a plurality of open gas distributions channels, a first portion of which is connected at one end to a first one of the plurality of gas delivery holes and at another end to a first one of the plurality of gas exhaust holes, a second portion of which is connected at one end to a second one of the plurality of gas delivery holes and at another end to a second one of the plurality of gas exhaust holes, and a third portion of which is connected at one end to said second one of the plurality of gas delivery holes and at another end to said first one of the plurality of gas exhaust holes.

Abstract: A cogeneration fuel cell system and associated methods of operation are provided that accommodate a demand for heat as well as a demand for electric power. The system is operated among various modes to balance heat and power demand signals. In general, a fuel cell system is coupled to a power sink and a heat sink, and a controller is adapted to respond to data signals from the power sink and the heat sink. As examples, such data signals from the heat sink may include a temperature indication or a heat demand signal (such as from a thermostat), and such data signals from the power sink may include a voltage or current measurement, an electrical power demand signal, or an electrical load.

Abstract: The present invention provides a method for enabling qualification of at least a portion of a fuel cell system. The method includes electronically obtaining at least one result of a test of the at least a portion of a fuel cell system and electronically comparing the at least one result to at least one qualifying criteria.

Abstract: A method includes (1) operating a fuel processing reactor to convert a hydrocarbon into reformate; (2) flowing reformate through a first pressure regulator to reduce the pressure of the reformate; (3) supplying reformate from the first pressure regulator to a fuel cell to generate electrical power; (4) flowing a portion of the reformate from the fuel processor to a second pressure regulator to reduce the pressure of the reformate while generating the electrical power with the fuel cell; and (5) supplying reformate from the second pressure regulator to the hydrogen purification system while generating the electrical power with the fuel cell.

Abstract: The invention provides an anode gas diffusion layer for a fuel cell and methods for preparation and use thereof. In particular, a hydrophilic anode gas diffusion layer promotes water transfer through the fuel cell. As an example, in one aspect, the invention provides a fuel cell system, including a fuel cell with an anode gas diffusion layer. The anode gas diffusion layer has a contact angle with water less than 140° (e.g., in some cases less than 120° or less than 100°). In another aspect, the invention provides a gas diffusion layer for a hydrogen electrode of a PEM fuel cell that includes a carbon fiber media having a water contact angle of less than 140°.

Abstract: A non-electrolytic layer that can be used, for example, in an electrode unit, a fuel cell, and/or a fuel cell stack is disclosed.

Abstract: The invention in the simplest form is a method and apparatus for reliably protecting against island situations with one or multiple power sources connected to an electric distribution grid. The method and apparatus detects variations in the voltage and frequency of the grid. An observed change in grid voltage causes a change in output power that is sufficient to cause an even larger change in grid voltage when the utility AC power source is disconnected. An observed change in grid frequency causes a change in phase or reactive output power that is sufficient to cause an even larger change in grid frequency. If several shifts in voltage or frequency happen in the same direction, the response to the change is increased in an accelerating manner.

Abstract: A simplified PEM fuel cell system is integrated with a fuel processor and an exhaust gas oxidizer to ensure clean emissions. The fuel cell has an operating temperature of 100-200° C., and utilizes reformate fuel having a carbon monoxide level greater than 1000 parts per million.

Abstract: A fuel cell stack includes a stack of flow plates, a first gasket that is compatible with a coolant and a second gasket that is incompatible with the coolant. The stack of flow plates includes openings to form a coolant passageway that communicates the coolant and a reactant manifold passageway. The second gasket forms a seal around the reactant manifold passageway between an adjacent pair of the plates. The first gasket forms a seal around the coolant manifold passageway between the adjacent pair of plates. At least one region of a particular plate may be associated with a reactant flow, and this plate may include internal passageways that extend between manifold passageways to communicate a coolant. A seal that is substantially permanent isolates the internal passageways from the region(s) of the fuel cell plate that may be associated with reactant flow(s).

Abstract: A fuel cell system includes a fuel cell stack, an enclosure housing the fuel cell stack and a blower. The blower is located inside the enclosure and is adapted to draw air from inside the enclosure to produce an air flow through the fuel cell stack and establish a negative pressure inside the enclosure with respect to a region outside of the enclosure.