Abstract: A fuel cell is described and which includes an ion exchange membrane; an electrode positioned in ion exchanging relation relative to the ion exchange membrane; a gas diffusion layer borne by the electrode and having an outwardly facing surface; a porous metal coating comprising one or more elements selected from the periodic table of elements and which has an atomic number of less than 75, and which is positioned at least in partial covering relation relative to the outwardly facing surface of the gas diffusion layer; and a current collector forcibly disposed in ohmic electrical contact with the porous metal coating.

Abstract: A power tap device for use in a fuel cell stack having a plurality of stackable items including separator plates, and membrane electrode assemblies each having an anode and cathode and configured to be respectively stacked between pairs of separator plates, comprises first and second major outer surfaces, the first major outer surface being electrically conductive, the second major outer surface being electrically conductive; and a dielectric separating the first major outer surface from the second major outer surface, wherein the power tap device is sized and arranged to be interposed between stackable items in the stack.

Abstract: A power system for supplying a power requirement of a load is described and which includes a plurality of DC power sources having at least one fuel cell, and which provides power to a load; and a control electronics assembly is provided and which is electrically coupled to the respective DC power sources, and which selectively reconfigures the plurality of DC power sources to substantially serve the changing power requirements of the load.

Abstract: A fuel cell is described and which includes an ion exchange membrane; an electrode positioned in ion exchanging relation relative to the ion exchange membrane; a gas diffusion layer borne by the electrode and having an outwardly facing surface; a porous metal coating comprising one or more elements selected from the periodic table of elements and which has an atomic number of less than 75, and which is positioned at least in partial covering relation relative to the outwardly facing surface of the gas diffusion layer; and a current collector forcibly disposed in ohmic electrical contact with the porous metal coating.

Abstract: A fuel cell power system, comprising a fuel cell which generates DC voltage; a plurality of energy storage devices selectively electrically coupled with the fuel cell; and circuitry for sequentially selectively electrically coupling and decoupling the respective energy storage devices to a load in a manner which approximates a voltage sine wave.

Abstract: A fuel cell power system comprising a fuel cell having a cathode and an anode adapted to be coupled to a fuel supply, and which is configured to produce electrical power having a current and voltage output; a controller electrically coupled with the fuel cell, and configured to selectively short the anode to the cathode of the fuel cell; and circuitry configured to measure resistance of the fuel cell in timed relation to the shorting.

Abstract: A fuel cell power system comprising a fuel cell having a cathode and an anode adapted to be coupled to a fuel supply, and which is configured to produce electrical power having a current and voltage output; a controller electrically coupled with the fuel cell, and configured to selectively short the anode to the cathode of the fuel cell; and circuitry configured to measure resistance of the fuel cell in timed relation to the shorting.

Abstract: Fuel cell power systems and methods of operating fuel cell power systems are described. According to one aspect, a fuel cell power system includes a fuel cell configured to generate electrical energy; switch mode power conditioning circuitry configured to electrically condition the electrical energy generated by the fuel cell, wherein the switch mode power conditioning circuitry comprises a controller configured to monitor an electrical status of the fuel cell and to adjust the conditioning of the electrical energy using the switch mode power conditioning circuitry responsive to the monitoring, wherein the controller is configured to provide a pulse width modulated control signal to control the switching of the switch mode power conditioning circuitry and to vary a duty cycle of the control signal to adjust the conditioning of the electrical energy using the switch mode power conditioning circuitry.

Abstract: A method of compensating a MOS gas sensor is described and which includes using a MOS gas sensor to provide a signal indicative of gas concentration of a target gas in an ambient; providing a signal representative of dew point of the ambient; and modifying the signal from the MOS gas sensor using the signal representative of dew point to simultaneously compensate for the effects of both temperature and relative humidity on the MOS gas sensor.

Abstract: A method of compensating a MOS gas sensor is described and which includes using a MOS gas sensor to provide a signal indicative of gas concentration of a target gas in an ambient; providing a signal representative of dew point of the ambient; and modifying the signal from the MOS gas sensor using the signal representative of dew point to simultaneously compensate for the effects of both temperature and relative humidity on the MOS gas sensor.

Abstract: A fuel cell power system, comprising a fuel cell which generates D.C. voltage while operating; an ultracapacitor which, in operation, is electrically coupled with a load and has a voltage condition; and a circuit which, in operation, electrically couples and decouples the fuel cell to the ultracapacitor based upon the voltage condition of the ultracapacitor.

Abstract: A method of speeding startup of a MOS gas sensor having a sensor element for sensing a target gas, and a heater configured to heat the sensor element, and which is responsive to a voltage applied thereto. The heater has an operating temperature which is selectively maintained by applying a first voltage thereto, and the heater further has a maximum recommended temperature which is selectively maintained by applying a second voltage thereto. The maximum recommended temperature is higher than the operating temperature, and the second voltage is higher than the first voltage. The method includes providing a third voltage to the heater which is greater than the second voltage for a predetermined amount of time which is selected to increase the temperature to a level not greater than the maximum recommended temperature in a shorter time period than if the second voltage is applied and maintained. A MOS gas sensor system and a fuel cell system also employ such a method.

Abstract: An ion exchange membrane fuel cell is described and which includes a module enclosing a membrane electrode diffusion assembly which has an active area defined by a surface area, and which produces an average current density of at least about 350 mA per square centimeter of surface area when supplied with a dilute fuel at a nominal voltage of about 0.5 volts.

Abstract: Fuel cell power systems, direct current voltage converters, fuel cell power generation methods, power conditioning methods and direct current power conditioning methods are provided. According to one aspect of the invention, a fuel cell power system includes a plurality of terminals adapted to couple with a load; a fuel cell configured to convert chemical energy into direct current electrical energy having a variable voltage potential; and a converter coupled intermediate the fuel cell and the terminals, the converter being configured to convert the direct current electrical energy having the variable voltage potential into direct current electrical energy having a substantially constant voltage potential.

Abstract: Fuel cell power systems and methods of controlling a fuel cell power system are provided. According to one aspect, a fuel cell power system includes a plurality of fuel cells electrically coupled with plural terminals and individually configured to convert chemical energy into electricity; and a digital control system configured to at least one of control and monitor an operation of the fuel cells. Another aspect provides a method of controlling a fuel cell power system including providing a plurality of fuel cells individually configured to convert chemical energy into electricity; electrically coupling the plurality of fuel cells; providing a first terminal coupled with the fuel cells; providing a second terminal coupled with the fuel cells; and coupling a digital control system with the fuel cells to at least one of monitor and control an operation of the fuel cells.

Abstract: A method for forming a membrane electrode diffusion assembly for use in an ion exchange membrane fuel cell is described and which includes, providing an ion conducting electrolyte membrane having opposite sides; and applying a first diffusion layer to one of the opposite sides of the ion conducting electrolyte membrane by the application of force sufficient to fabricate a resulting membrane electrode diffusion assembly which has an optimal operational temperature range when utilized in an ion exchange membrane fuel cell of less than about 95 degrees C.

Abstract: A proton exchange membrane fuel cell power system for producing electrical power is described and which includes a plurality of discrete fuel cell modules having at least two membrane electrode diffusion assemblies, each of the membrane electrode diffusion assemblies having opposite anode and cathode sides; a pair of current collectors are individually disposed in juxtaposed ohmic electrical contact with opposite anode and cathode sides of each of the membrane electrode diffusion assemblies; and individual force application assemblies apply a given force to the pair current collectors and the individual membrane electrode diffusion assemblies. The proton exchange membrane fuel cell power system also includes an enclosure mounting a plurality of subracks which receive the discrete fuel cell modules. Additionally, a control system is disclosed which optimizes the performance parameters of the discrete proton exchange membrane fuel cell modules.