Utc Power Corporation

Utc Fuel Cells, LLC

Ballard Power Systems Corporation

Jeremy P Meyers

Robert Mason Darling

Craig E Evans

Ryan J Balliet

Carl Anthony Reiser

Tommy Skiba

Thomas D Jarvi

Evan Christopher Rege

Deliang Yang

Nileshkumar Trambaklal Dave

David D Johnson

Richard D Breault

Leslie L Van Dine

John H Whiton

Sitaram Ramaswamy

Robin J Guthrie

David A Niezelski

Timothy W Patterson

Jung S Yi

Chris Vargas

Lawrence J Bregoli

Jeffrey G Lake

Yu Wang

Javier Resto

Emily A Dykeman

George S Hirko

Timothy A Bekkedahl

Elizabeth A Allen

Mark W Layaw

James R Geschwindt

A fuel cell is provided that includes a water transport plate separating an air flow field and a water flow field. The driving force for moving water across the water transport plate into the water flow field is produced by a differential pressure across a restriction. The restriction is arranged between an air outlet of the cathode water transport plate and a head of a reservoir that is in fluid communication with the water flow field.

Water management for a fuel cell

To mitigate bubble blockage in water passageways (), in or near reactant gas flow field plates () of fuel cells (), passageways are configured with (a) intersecting polygons, obtuse angles including triangles, trapezoids, or (b) hydrophobic surfaces (), or (c) differing adjacent channels (), or (d) water permeable layers () adjacent to water channels or hydrophobic/hydrophilic layers ().

Fuel cell coolant bubble control

A fuel cell () includes a cathode catalyst () for receiving a first reactant and an anode catalyst () for receiving an expected amount of a second reactant. The cathode catalyst () and the anode catalyst () respectively catalyze the first reactant and the second reactant to produce an electrochemical reaction that generates a flow of electrons between the cathode catalyst () and the anode catalyst () The amount of the first reactant consumed in the electrochemical reaction corresponds to a threshold amount of the second reactant needed to generate a forward flow of the electrons from the anode catalyst () to the cathode catalyst (). A portion () of a fuel cell flow field includes a feature (, W, D) that restricts consumption of the first reactant.

Stabilized fuel cell flow field

To mitigate bubble blockage in water passageways (), in or near reactant gas flow field plates () of fuel cells (), passageways are configured with (a) cross sections having intersecting polygons or other shapes, obtuse angles including triangles and trapezoids, or (b) hydrophobic surfaces (), or (c) differing adjacent channels (), or (d) water permeable layers () adjacent to water channels or hydrophobic/hydrophilic layers (), or (e) diverging channels ().

An inlet fuel distributor (-) has a permeable baffle () between a fuel supply pipe () and a fuel inlet manifold () causing fuel to be uniformly distributed along the length of the fuel inlet manifold. A surface () may cause impinging fuel to turn and flow substantially omnidirectionally improving its uniformity. Recycle fuel may be provided () into the flow downstream of the fuel inlet distributor. During startup, fuel or inert gas within the inlet fuel distributor and the fuel inlet manifold may be vented through an exhaust valve () in response to a controller () so as to present a uniform fuel front to the inlets of the fuel flow fields ().

Permeable inlet fuel gas distributor for fuel cells

A PEM fuel cell power plant includes fuel cells, each of which has a cathode reactant flow field plate which is substantially impermeable to fluids, a water coolant source, and a fluid permeable anode reactant flow field plate adjacent to said water coolant source. The anode reactant flow field plates pass water from the coolant sources into the cells where the water is evaporated to cool the cells. The cathode flow field plates prevent reactant crossover between adjacent cells. By providing a single water permeable plate for each cell in the power plant the amount of water present in the power plant at shut down is limited to a degree which does not require adjunct water purging components to remove water from the plates when the power plant is shut down during freezing ambient conditions. Thus the amount of residual ice in the power plant that forms in the plates during shut down in such freezing conditions will be limited. The power plant can thus be restarted and brought up to full operating power levels quickly due to the reduced amount of ice that must be melted during startup. The power plant is thus well suited for use in powering vehicles.

Non-circulating coolant PEM fuel cell power plant assembly with low thermal mass

Fuel cells () have water passageways () that provide water through reactant gas flow field plates () to cool the fuel cell. The water passageways may be vented to atmosphere (), by a porous plug (), or pumped () with or without removing any water from the passageways. A condenser () receives reactant air exhaust, may have a contiguous reservoir (), may be vertical, (a vehicle radiator, FIG.), may be horizontal, contiguous with the top of the fuel cell stack (, FIG.), or below () the fuel cell stack (). The passageways may be grooves () or may comprise a plane of porous hydrophilic material () contiguous with substantially the entire surface of one or both of the reactant gas flow field plates. Air flow in the condenser may be controlled by shutters (). The condenser may be a heat exchanger () having freeze-proof liquid flowing through a coil () thereof, the amount being controlled by a valve (). A deionizer () may be used.

Fuel cells evaporative reactant gas cooling and operational freeze prevention

Fuel cells () have minute water passageways () that provide water through one or both reactant gas flow field plates () of each fuel cell, whereby the fuel cell is cooled evaporatively. The water passageways () may be vented by a porous plug (), or by a microvacuum pump () that does not pump any water from the passageways, or simply vented () to atmosphere. A condenser () may have a contiguous reservoir (); the condenser () may be vertical, such as a vehicle radiator (FIG.), or may be horizontal, contiguous with the top of the fuel cell stack (, FIG.). The passageways may be grooves () in the reactant gas flow plates () or the passageways may comprise a plane of porous hydrophilic material () contiguous with substantially the entire surface of one or both of the reactant gas flow field plates.

Fuel cells evaporatively cooled with water carried in passageways

A plurality of cooler plates () are disposed between fuel cells () in a stack () and have protrusions () which include coolant inlet and outlet channels (). The protrusions are surrounded by an elastomeric sealant material () which forms a seal with the manifold structures () to form coolant inlet and outlet manifolds (). The sealant material prevents coolant from entering fuel cells along the edges thereof, thereby preventing the fuel cells from being poisoned by the coolant. The coolant inlet and outlet manifold structures () also define reactant gas manifolds ().

Easily isolated, oversized fuel cell stack cooler plates

A PEM fuel cell assembly includes cooler plates () with internal coolant manifolds () isolated from the cell stack assembly by an isolation gap () to minimize the risk of contamination of the cells by antifreeze. The internal coolant manifolds are formed by seal assemblies (), each disposed between inlet or outlet openings () in projections () of each cooler plate extending outwardly from the fuel cell planform () to provide a gap (), which may be used as an air turn manifold. Flanges () with through holes () may receive tie rods to assist assembly of a fuel cell stack with the cooler plate.

PEM fuel cell stack assembly with isolated internal coolant manifold

In a fuel cell stack (), a larger number of fuel cells () are interposed between successive cooler plates () without creating excessively high temperatures in those fuel cells () which are remote from the cooler plates, by virtue of increased air flow in air flow field channels () which are deeper in fuel cells () remote from the cooler plates, compared with the flow field channels () which are in fuel cells () adjacent to the cooler plates. The thickness of air flow field plates () may be increased to accommodate the increased depth of the air flow channels (). Fuel cells () adjacent the cooler plate may have air flow field channels () which are more shallow than normal whereby increased air utilization therein will be balanced by decreased air utilization in the cells () having deeper air flow channels (); in this case, the channels () may be normal or deeper than normal.

Varied fuel cell oxidant flow channel depth resulting in fewer cooler plates

Each cell of a fuel cell stack is provided, between the anodeand cathodes, with either (a) a permanent shunt () which may be a discrete resistor (), a diode (), a strip of compliant carbon cloth (), or a small amount of conductive carbon black () in the ionomer polymer mixture of which the proton exchange membrane () is formed, or (b) a removeable shunt such as a conductor () which may be rotated into and out of contact with the fuel cell anodes and cathodes, or a conductor () which may be urged into contact by means of a shape memory alloy actuator spring (), which may be heated.

Growing community of inventors

West Hartford, CT, United States of America

Jeremy P Meyers