Abstract: A fuel cell system having a fuel cell stack (9) employs a group of fuel cells between corresponding cooler plates (55). The system utilizes single phase coolant, the outflow of the coolant plates (55) being divided into a flow (78) just sufficient to provide adequate steam (68, 79) to a fuel reformer (58), the remainder of the coolant outlet flowing (76) directly to heat recovery and utilization apparatus (77), which may include fuel cell power plant accessories (85), such as chillers or boilers.

Abstract: A fuel cell stack (7) with output lines (8, 9) has a bank of supercapacitors (10) or batteries (10a) connected across the output lines, either directly or through a DC/DC converter (22). The fuel cell stack receives fuel either from a reformer (13) or a source (13a) of hydrogen. Power is supplied through a power conditioning system (15) to a load (16), all under the control of a controller (19). The supercapacitors or batteries receive additional charge from excess power when there is a sudden decrease in the load, and provide charge to the output power lines (8, 9) when there is a sudden increase in load demand. In one embodiment, the voltage of the supercapacitors or batteries always follow the voltage of the fuel cell stack, thereby providing or receiving commensurate charge. With the DC/DC converter, the supercapacitors or batteries may be operated at voltages which are a multiple or a fraction of fuel cell stack voltage, and may have voltages boosted or bucked to aid in response to transients.

Abstract: Fuel cells (16) include a proton exchange membrane (18) with cathode catalyst (24) and anode catalyst (20) on opposing surfaces thereof. An anode support plate (21) includes a hydrophilic substrate (22) and a cathode support plate (25) includes a hydrophilic substrate (26) and a contact bilayer (diffusion layer) (24). Water transport plates (12, 14) are adjacent corresponding support plates. Upon shut down of the fuel cell stack, the support plates (21, 25) fill to 60%–80% of their water capacity, thereby to provide water (from melting ice) upon a bootstrap start of the frozen cells. In one embodiment, the amount of water is controlled by the pressure differential between the coolant and the reactant gases; in another embodiment, the amount of water is controlled by having hydrophobic regions (93) substantially uniformly dispensed in a hydrophilic substrate (94) in either the support plates (22a) or the contact bilayer (27).

Abstract: A plurality of fuel cell stacks (8, 8a, 9, 9a) have their cathode ends (11, 12) contiguous with either a common current collector (15a–15d) or respective current collectors (15a, 15b) which may be separated by electrical isolation (27a, 27b). The cathode-to-cathode relationship protects the cathode of each of the stacks from cold ambient environments, thereby permitting improved cold starts and mitigation of performance loss as a result of cold starts as well as freeze/thaw cycles. Heaters (30, 30a–30d) may be provided in current collectors, or in or between electrical isolation. Four stacks may share one current collector, or each may have its own current collector.

Abstract: A PEM fuel cell assembly includes cooler plates (10) with internal coolant manifolds (25) isolated from the cell stack assembly by an isolation gap (28) to minimize the risk of contamination of the cells by antifreeze. The internal coolant manifolds are formed by seal assemblies (24), each disposed between inlet or outlet openings (14, 15) in projections (16) of each cooler plate extending outwardly from the fuel cell planform (20) to provide a gap (28), which may be used as an air turn manifold. Flanges (40) with through holes (41) may receive tie rods to assist assembly of a fuel cell stack with the cooler plate.

Abstract: A fuel cell stack has an air inlet manifold (21), an air turnaround manifold (22) and an air exit manifold (23); a coolant inlet is adjacent said air exit manifold; a fuel inlet manifold (16) is connected through a turnaround manifold (17) to a fuel exit manifold (18) remote from said coolant inlet. Fuel recycle is taken from the fuel manifold where the temperature is warmer than it is near the coolant inlet; recycle air for humidifying and heating inlet air is taken from the air turnaround manifold (22), and may either be recycled air provided by a recycle pump (31), or it may utilize an enthalpy recovery device (38) to transfer heat and humidity from an outflow chamber (41) to an inflow chamber (39).

Abstract: An auxiliary load (148) for a fuel cell stack (102) is alternatively connected and disconnected from the fuel cell external circuit (177, 178) by a switch (200) in response to a switch control (201), repetitively, during startup and shutdown. The switch may be an insulated gate bipolar transistor (208) which is turned on and off by hunting between an upper limit voltage (207) and a lower limit voltage (208), which may be performed by compare circuits (205, 206), by the controller (202), or by commercially available voltage responsive hysteresis switches. Schedules of duty cycle as a function of cell stack voltage for startup (212) and shutdown (213) control a pulse width modulator (215) which operates the switch. Controls (229, 231) may limit the modulation so that the auxiliary load does not overheat, in response to temperature (221) of the load or a voltage/power model (235). The auxiliary load may comprise a heater in a water accumulator (247), an air intake (257) or an enthalpy recovery device (262).

Abstract: In a fuel cell stack (11a), a larger number of fuel cells (18–21, 33–36) are interposed between successive cooler plates (13–15) without creating excessively high temperatures in those fuel cells (33–36) which are remote from the cooler plates, by virtue of increased air flow in air flow field channels (30a) which are deeper in fuel cells (30–36) remote from the cooler plates, compared with the flow field channels (30, 30b) which are in fuel cells (18–21) adjacent to the cooler plates. The thickness of air flow field plates (29b) may be increased to accommodate the increased depth of the air flow channels (30a). Fuel cells (18a) adjacent the cooler plate may have air flow field channels (30b) which are more shallow than normal whereby increased air utilization therein will be balanced by decreased air utilization in the cells (33–36, 33a) having deeper air flow channels (30a); in this case, the channels (30a) may be normal or deeper than normal.

Abstract: A prime mover (28) in a heat recovery system drives an induction generator (8) which feeds power to a utility grid (9) through a breaker (10) but also powers a load including auxiliary induction motors (11, 12). To provide acceptable waveform and power factor, the auxiliary equipment is driven through IGBT switched bridge converters (13) by DC voltage (15) generated by an IGBT switched bridge converter (13a), instead of three-phase diode rectifiers (16). The switched bridge converter controller (14a) is responsive to a system process controller (23a) which causes the switched bridge controller (13a) to be driven in response to the voltage (26) and current (27) on the generator bus (17). This eliminates the need for harmonic filters (18) and power factor capacitors (20) while improving the quality of the power generated. The controller (23a) trips the breaker if the voltage, frequency or power factor is out of limits.

Abstract: A jack plate (9) moveable upwardly and downwardly between various positions has a trim tab (28) disposed on a fixed portion (10) of the jack plate near the base of the transom (11) of a boat. The moveable portion (12) of the jack plate has a push cap (44) that, at a pickup position of the jack plate, pushes a rod (43) which rotates a lever (38) to move an arm (33) to push the trim tab (28) into an operative position aft of and below the hull of the boat. Above the pickup position, the push cap does not contact the rod; a return spring (50) causes the trim tab (28) to rotate upwardly, into a position where it is ineffective.

Abstract: The output of a high power pulsed or CW laser (22), which may be mounted on a vehicle (17) is reflected from a convex mirror (27) to a concave mirror (29) that is displaced radially outward on a rotating structure (14) from the convex mirror by at least two beam diameters so that each pulse emanates from a position around a circle which is displaced from adjacent pulses by at least the diameter of the beam, thereby to minimize thermal blooming, or the position of a CW output laser beam is slewed. Directing the beams so that all of them will converge at a target area which is a given range from the apparatus is achieved by moving the convex mirror axially in response to range control signals provided through brushes (47) and slip rings (46). The rotating structure (14) including the laser waveguide (24) is journaled by bearings (50, 51) for rotation by a gear in response to a pinion (34) and gear reduction (37) driven by a motor (38).

Abstract: A package (6) includes a frame (7) into which product (34–37) is loaded from the back prior to being closed off by a card (8) which adheres to the back of the frame. The frame has openings (20–23) shaped to receive the product, each opening having retainers (50–53) extending forwardly from the edges thereof, each retainer shaped to engage a particular portion (40–42, 45) of the product.

Abstract: During startup or shutdown of a fuel cell power plant, the electric energy generated by consumption of reactants is extracted by a storage control (200) in response to a controller (185) as current applied to an energy storage system 201 (a battery). In a boost embodiment, an inductor (205) and a diode (209) connect one terminal (156) of the stack (151) of the battery. An electronic switch connects the juncture of the inductor and the diode to both the other terminal (155) of the stack and the battery. The switch is alternately gated on and off by a signal (212) from a controller (185) until sufficient energy is transferred from the stack to the battery. In a buck environment, the switch and the inductor (205) connect one terminal (156) of the stack to the battery. A diode connects the juncture of the switch with the inductor to the other terminal (155) of the fuel cell stack and the battery.

Abstract: A PEM fuel cell system (19) has a multifunction oxidant manifold (98) disposed contiguously beneath a fuel cell stack (20), serving as coolant accumulator (28). An electric heater (45) is powered by the fuel cell electrical output (47, 51) during frozen startup. Auxiliary pump (54) and conduits (55, 57, 58) forces water (28) above oxidant pressure in upper coolant manifold (41), into the oxidant flow fields to be warmed before flowing from the oxidant exhaust to the accumulator to melt additional ice. Alternatively, melted coolant is forced by oxidant pressure into coolant channels for heating. Conduit (61) conducts coolant from the coolant flow fields to the accumulator. A condensing heat exchanger (65) embedded in accumulator coolant receives oxidant exhaust. A condensing heat exchanger (70) has cold inlet air (75) and warm moist oxidant exhaust (72) on opposite sides, condensing liquid into the accumulator.

Abstract: Inlet air (15) humidified in an air bubbling (or other) humidifier (35) that receives water from a tank (36) is sent to a hydrogen generator (27) along with vaporized (23) diesel fuel (22) to produce hydrogen and carbon monoxide (28) for either (a) mixing with the mainstream of exhaust (18) fed to a catalytic converter (30) or (b) regenerating a pair of NOx adsorption traps (38, 39), thereby reducing oxides of nitrogen (NOx), to provide system exhaust (32) which may have less than 0.40 grams/bhp/hr of NOx and 0.28 grams/bhp/hr of non-methane hydrocarbons. In other embodiments, unhumidified air mixed with fuel feeds a homogeneous non-catalytic partial oxidizer (27) to provide the required hydrogen and carbon monoxide.

Abstract: A catalytic partial oxidizer (30) provides syngas (hydrogen and carbon monoxide) to an apparatus intermittently using syngas such as valves (34) feeding NOx traps (35), for brief periods of time. During turndown times when syngas is not being used, either the output of the CPO is diverted (33) to the inlet (13) of an engine (12) through the engine gas recycle (EGR) system (43-46), or the amount of fuel (19) and exhaust (23) applied to the CPO is reduced (24, 26; 59, 60) so that the CPO merely stays warm and in a reduced state, thereby being ready to restart immediately. A mini-CPO (62) may provide syngas and heat to the major CPO (30) during the turndown time when syngas is not being used by the NOx traps.

Abstract: A vane (31) at the juncture of orthogonal conduits (25–28) allows flow of air to and from the air inlet/outlet manifold (12) of a fuel cell stack (11) when it is disposed in a first position, and totally blocks the conduits (25, 26) so as to isolate the air flow fields of the fuel cells (17, 18) when in a position normal to the first position. A vane (41) can comprise the divider of the air inlet/outlet manifold when in a vertical position, and totally block off the manifold when in a horizontal position. A vane (59) can align with the divider (24) of an air inlet/out manifold when in a vertical position, and block the passage between the manifold and conduits (44, 46) when in a horizontal position. Similar vanes may be used for single-valve selection of flow or containment of fuel reactant gas.

Abstract: A single lean NOx trap (8) has an inlet manifold (10) with baffles (18–20) to divide the inlet manifold into three flow paths (11–13). Each flow path has a thermal reformer (24–26; CPO, (POX, or ATR) with an electric heater provided electric power by related lines (29–31). Fuel from a source (50) is controlled (45–46) to apply pulses of fuel through nozzles (40–42) into each corresponding path (11–13) in turn. A plurality of diesel particulate filters (14) are disposed in the flow paths (11–13) upstream of the lean NOx trap (8). A diesel oxidation catalyst (53) is disposed downstream of the lean NOx trap.

Abstract: Fuel is provided to an inlet (14) of a cascade region (15) which has a plurality of stages (17-23), each of which divides fuel flow evenly into a pair of corresponding slots (24-26). The flow is then spread across a floor surface (41) of a cascade exit header (40), the flow spreading into areas between the slots. The flow is then directed into an open cavity which is in fluid communication with the inlets of the fuel flow fields (12) of the fuel cells, reaching the fuel flow field inlets uniformly and simultaneously.

Abstract: A trim tab (18, 204) hinged (19) at the bottom edge of a boat transom (12, 179) is rotated into a position below the boat when the drive (58, 186) is in a lowest-most trim position, and is raised up, when the drive is above a selected pickup trim position. A push tube (58) connected to the motor (16) operates a push rod (49) and a trim tab (18). A push bar (96, 97) is moved by the drive, causing pieces (104, 105) to rotate trim tabs (18a). A fluidic slave cylinder (142) is operated by a master cylinder (134) or by a pump (148) responding to a position detector (150). Levers (164, 167) may be connected by a cable (155). A hydraulic master cylinder (195) is disposed on a part (186) of an outdrive that rotates for trim, its cylinder rod (200) contacting a fixed part (184), driving fluid to a slave cylinder (201) mounted on a fixed part (183) with its piston rod (202) moving a trim tab (204).