Abstract: 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.

Abstract: A fuel cell plate including a first plate having a first header edge defining a first header aperture, the first header edge having a first break and a substantially aligned second plate having a second header edge defining a second header aperture, the second header edge having a second break. The fuel cell plate, well suited for use in a vehicle fuel cell stack, for removing water from a fuel cell stack header is disclosed.

Abstract: A fuel cell plate having a first plate having an inlet aperture and a second plate disposed against the first forming a conduit. The fuel cell plate, well suited for use in a vehicle fuel cell stack, for reducing water retention in a fuel cell without increasing the number of required components and fabrication cost of the fuel cell plate is disclosed.

Abstract: A fuel cell assembly is disclosed that utilizes a fuel cell plate having hydrophobic portions adjacent an inlet and an outlet formed therein, and a hydrophilic portion formed in the flow channels of the fuel cell plate adjacent the hydrophobic portions, wherein the hydrophilic portion and the hydrophobic portion facilitate the transport of liquid water from the fuel cell plate.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus for heating a fuel cell assembly is disclosed, wherein a means for heating is disposed in a manifold of the fuel cell assembly and the means for heating causes the manifold to be heated to militate against fluid condensation and ice formation in the fuel cell assembly.

Abstract: 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.

Abstract: A device and method to extract water from a moisture-rich fuel cell flowpath. A water transport unit is integrated into the fuel cell so that liquid water stagnation within flow channels and manifolds is reduced. In one embodiment, the device includes numerous flowpaths that include an active region and an inactive region. The water transport unit includes a hydrophilic member such that upon passage of a fluid with the excess water through the inactive region of the device flowpath and into the presence of the hydrophilic member, it absorbs excess water from the fluid.

Abstract: 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.

Abstract: A fuel cell system is described having a fuel cell stack including a PEM fuel cell having an anode and a cathode, the fuel cell stack further including an anode outlet and an anode inlet, a hydrogen storage device in communication with the anode inlet and configured to supply a hydrogen gas to the fuel cell stack, and an accumulation reservoir in communication with the anode outlet of the fuel cell stack. The accumulation reservoir is configured to accumulate a quantity of water and an exhaust stream including the hydrogen gas during a purge event and resupply the exhaust stream to the fuel cell stack after the purge event is complete. The accumulation reservoir can be a second fuel cell stack. A method of operating the fuel cell system is also provided.

Abstract: A bipolar plate for a fuel cell is disclosed including a first unipolar plate having an active surface with a plurality of flowfield channels formed therein. The first unipolar plate further includes an inlet header disposed at a first end of the unipolar plate that is in communication with the active surface, and an outlet header disposed at a second end of the unipolar plate having an exhaust opening formed therethrough. A peripheral edge of the exhaust opening is chamfered and is also in communication with the active surface. The chamfered exhaust opening forms a water removal channel in the bipolar plate. A fuel cell stack including the bipolar plate is also disclosed.

Abstract: A method for depositing a hydrophilic coating on flow field plates or bipolar plates and manifolds in a fuel cell stack after the stack is assembled. The method includes preparing a solution that contains hydrophilic nano-particles suspended in a suitable solvent. The cathode and anode inlet and outlet manifolds and the cathode and anode flow channels are filled with the solution. The solution is then pumped out of the stack using, for example, a stream of nitrogen. The stack is allowed to dry, using heat if desirable, to provide a film of the nano-particles formed on the anode and cathode flow channels and manifolds within the stack.

Abstract: A fuel cell stack is disclosed that utilizes a porous material internally disposed in the fuel cell outlet manifolds, wherein the porous material facilitates the transport of liquid water from the plate outlets thereby minimizing the accumulation of liquid water in the fuel cell stack.

Abstract: An assembly for a fuel cell including an electrically conductive fluid distribution element including a flow field disposed on a surface of the element, wherein the flow field includes a plurality of channels for carrying the gaseous reactants of the fuel cell. The assembly also includes an electrically conductive member disposed at the surface of the element to serve as a gas diffusion media. The channels of the element include a plurality of sidewalls formed in various orientations, and the orientations of the side-walls form a cross-sectional geometry of the channel such that water collection regions are formed at an interface of the electrically conductive fluid distribution element and the electrically conductive member, and at a bottom portion of the channel.