Plug Power Inc.

Mti Microfuel Cells Inc.

Charles Michael Carlstrom, Jr

Russel Hugh Marvin

David H Leach

James D'Aleo

Constantinos Minas

Charles R Elder

Milton H Nelson

Michael Anthony Cacioppo

Mathew J Cusack

John R Miller

Russ Marvin

Michael M Walsh

William P Acker

Dustan L Skidmore

Keith Garrette Brown

Robert S Hirsch

Louis Andrew Schick

David Anthony DeAngelis

John Eric Meschter

John Guido Piccirillo

Mark C Mendrick

Robert J Miller

Norman Peschke

Megan A Fannon

William B Maynard

Michael L Chen

James K Prueitt

Gary D Antonelli

Sampath Venkataswamy

Amit Chaugule

A fuel cell stack includes an endplate assembly having a structural endplate. An insulator plate has a second exterior surface contacting a first interior surface of the structural endplate and a second interior surface on an opposite side of the insulator plate. A third plate has a third exterior surface contacting the second interior surface and a third interior surface on an opposite side of the third plate relative to the insulator plate. The third interior surface and third exterior surface are substantially flat. The second interior surface and the third exterior surface contact each other substantially continuously in a longitudinal direction and a lateral direction, and are flat and substantially parallel to each other. The second exterior surface is contoured such that the second exterior surface is not flat and is substantially non-parallel relative to the third interior surface.

Fuel cell stack

A fuel cell system which includes a fuel distribution structure that uniformly distributes vaporizing fuel to a fuel cell is provided. As the fuel travels in a flow field channel in the fuel distribution structure, it is substantially converted to a vapor by the heat of the fuel cell operation in such a manner that the resulting vapor pressure works to substantially uniformly distribute fuel evenly outwardly across substantially the entire active area of the anode aspect of one or more membrane electrode assemblies in the system, and whereby localized, uneven 'hot spots' of fuel at the anode aspects are substantially prevented. A pair of enthalpy exchanger and heat spreader assemblies include a cathode current collector element that also has a heat spreader plate that collects and redirects heat in the fuel cell system, the assembly acting to manage the heat, temperature and condensation in the fuel cell system.

Direct oxidation fuel cell system with uniform vapor delivery of fuel

A spring loaded direct oxidation fuel cell assembly reduces the effects of precompression relaxation. A near flat spring and a distribution plate form a spring assembly that is disposed between a membrane electrode assembly and one of the current collectors in the fuel cell. The components are assembled into a fuel cell assembly and are precompressed, and a spring yielding process is performed. While precompression is being applied, a set of pins and a plastic frame are insert molded around the fuel cell assembly to hold the components in place. Subsequently, as the precompression relaxes, the spring assembly forces act to maintain an evenly distributed compression on the MEA, thereby compensating for the loss of precompression. A related method of manufacturing a fuel cell assembly is provided.

Method for fuel cell assembly with springs and pins

A fuel cell system having internal pushback of water, with a compact, thermally integrated enthalpy exchanger enabling effective hydration control in a small fuel cell system is provided. The enthalpy exchanger provides for the moisture in the fuel cell effluent to be used to humidify the incoming air stream to allow the fuel cell to be operated at higher temperatures while avoiding dry out. The enthalpy exchanger includes a moisture permeable membrane which collects moisture from the exhaust flow and makes this moisture available to an incoming air stream, thus humidifying the incoming air stream. In addition, the waste heat from the fuel cell reactions is transferred to the incoming air stream. The exhaust stream from the anode can also be used to provide additional moisture and heat to the enthalpy exchanger to be added to the incoming air stream. A water separator is also provided in one embodiment.

Method and apparatus for internal hydration of a fuel cell system

A wide-area electrostatically-actuated shutter is provided that includes a thin, flexible, diaphragm that is placed between two rigid electrode structures. In one embodiment of the invention, the diaphragm has a set of openings in it. These openings overlap with corresponding openings in one of the rigid electrodes such that when the diaphragm is contiguous to that electrode, the openings provide apertures through which vaporous fuel can flow. The opposite electrode does not have overlapping openings, thus it forms a seal that prevents gas or vapor from passing through it when the diaphragm is in contact with the opposite electrode. The shutter is actuated electrostatically by an associated driver that applies a voltage to the diaphragm such that when the high voltage is applied to the diaphragm, the diaphragm is attracted to the fixed electrode that is tied to ground. Alternatively, when is desired to place the shutter in the opposite position, the diaphragm is placed at ground, which, in turn, pulls it towards the fixed electrode that is at a high voltage, to adjust the shutter. The shutter can be rapidly opened and closed at a high frequency in a PWM mode or a PFM mode.

Electrostatically actuated shutter and array for use in a direct oxidation fuel cell

A technique includes applying a charge to a flow plate of a fuel cell stack and depositing a material on at least a portion of the flow plate in response to the charge. In some embodiments of the invention, the technique may be applied to a fuel cell stack that includes a passageway to communicate a coolant. As a result of the technique, the fuel cell stack may include a layer to line the passageway to electrically insulate the stack from the coolant.

Forming a layer on a flow plate of a fuel cell stack

A fluid flow plate for a fuel cell includes a first face and a fluid manifold opening for receiving a fluid and at least one flow channel defined within the first face for distributing a reactant in the fuel cell. A dive through hole is defined in and extends through the fluid flow plate. The dive through hole is fluidly connected to the fluid manifold opening by an inlet channel, defined within an opposite face of the plate. The dive through hole and the inlet channel facilitate transmission of a portion of the fluid to the flow channel. A groove, adapted to receive a sealing member, is also defined within the first face and/or the opposite face. The sealing member may comprise a gasket which seals the respective fluid manifolds, thereby preventing leaking of fluid.

Fuel cell fluid flow plate for promoting fluid service

A hydration system for a fuel cell includes a fluid flow plate having an inlet fluid opening for receiving a hydration fluid, a plurality of reactant flow channels defined in the fluid flow plate, at least one land interposed between the flow channels, and at least one hole defined in and extending through the land. The hole may be fluidly connected to the inlet fluid opening, thereby allowing a portion of the fluid to aid in hydration of a membrane of the fuel cell. A hydration channel also formed in the land may extend from an outlet of the hole to further aid membrane hydration.

Distribution of hydration fluid in a fuel cell

A fuel cell stack assembly includes a stack of fuel cell flow plates that include fluid passageways; pipes to communicate fluids with the fluid passageways; an end plate; and a dielectric manifold. The end plate supports a compressive load to compress the stack, and the end plate includes openings. The manifold is located between the end plate and the stack to communicate the fluids between the pipes and the fluid passageways. The manifold at least partially extends through the openings in the end plate to form a sealed connection between the manifold and the pipes.

Clamping system for a fuel cell stack

An end plate assembly is disclosed for use in a fuel cell assembly in which the end plate assembly includes a housing having a cavity, and a bladder receivable in the cavity and engageable with the fuel cell stack. The bladder includes a two-phase fluid having a liquid portion and a vapor portion. Desirably, the two-phase fluid has a vapor pressure between about 100 psi and about 600 psi at a temperature between about 70 degrees C. to about 110 degrees C.

End plate assembly having a two-phase fluid-filled bladder and method for compressing a fuel cell stack

In one aspect, a first (flow field) plate of a fuel cell assembly includes a first flow channel(s) thereon. Fluid is conducted to the flow channel through an opening extending through the first plate. An adjacent second plate cooperates in providing surface(s) for a flow path between a manifold and the opening. Additional surface(s) may cooperate in providing the flow path and/or structural support therefor. A formation on the first plate may impede fluid communication from the manifold plate on a plate face including the first flow channel. The formation may provide structural support in a (e.g., PEM-type) fuel cell assembly, and/or a clamping and/or gasketing function for a membrane electrode assembly. A second flow path may similarly be provided for humidification of the (e.g., reactant) fluid. The second flow path may include flow regulator(s) and/or metering orifice(s). The second plate may include a second flow channel thereon. Flow path(s) for the second plate may be configured to provide the aforementioned surface(s) for the flow path(s) for the first plate without interference among fluid service for each plate. A multiplication of manifolds for a fluid may allow a manifold to omit service for a plate, where a different manifold may service the omitted plate.

Fuel cell assembly unit for promoting fluid service and design flexibility

Fluid flow plate for distribution of hydration fluid in a fuel cell

In one aspect, a fuel cell assembly may include one or more (e.g., PEM-type) fuel cell(s). Fluid(s) service(s) for the fuel cell assembly may include reactant fluid(s) service(s) such as service(s) of fuel(s) and/or oxidant(s), along with humidification service(s). A pulsator may be positioned at any entrance and/or exit for the fluid manifolds. Such pulsator(s) may serve to introduce pressure variation(s) along part(s) of flow path(s) extending in the fuel cell assembly. In one example, with respect to an anode side of a fuel cell, the pressure variation(s) may serve to purge a nitrogen blanket from the anode side of the MEA so reformate including hydrogen may be supplied for electrochemical reaction. With respect to a cathode side of the fuel cell, the pressure variation(s) may serve to remove a nitrogen and/or carbon dioxide blanket and product fluid from the cathode side of the MEA so air containing oxygen may be supplied for the electrochemical reaction. Also, excess humidification fluid may be removed. A greater power density may be obtained. Pressure variation(s) may be configured to dynamically inflect the MEA to assist mechanical mixing(s) in promoting flow field fuel service(s) and/or increasing power density.

Fuel cell with selective pressure variation and dynamic inflection

A fluid flow plate is preferably formed with conductive member(s) and non-conductive material(s). The conductive member(s) and/or the non-conductive material(s) form portion(s) of land(s) and/or flow channel(s) on face(s) of the plate. The flow channel(s) pass between and/or among the land(s). The flow channel(s) can be optimized to service fluid(s) for a fuel cell assembly. The conductive member(s) form electrical path(s) between, among, about and/or around position(s) on the face(s) of the plate. The electrical path(s) serve to conduct electrical current generated by the fuel cell assembly. The non-conductive material(s) can form brace(s) for, and/or seal(s) with, portion(s) of the flow channel(s). The non-conductive material(s) can form portion(s) of a periphery of the face(s) of the plate, and/or portion(s) of any appropriate geometric feature(s) for the plate. The non-conductive material(s) can be injection-molded. The non-conductive material(s) can form means for aligning the fluid flow plate with an adjacent plate. The non-conductive material(s) can form means for maintaining clamping pressure on a component between the fluid flow plate and an adjacent plate.

Growing community of inventors

Saratoga Springs, NY, United States of America

Charles Michael Carlstrom, Jr