Abstract: The frequency of sending system messages carrying quality-of-service information through a communications network is increased with increased communications traffic load in the network.

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 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: 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: 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 is disclosed and which includes an anode and a cathode and which produces a voltage output which is supplied to a load; an electrical energy storage device is provided; and a controller is electrically coupled to the fuel cell, and which periodically shunts the voltage output of the fuel cell between the anode and cathode by electrically coupling the electrical energy storage device to the anode and cathode of the fuel cell.

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 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: 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: 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.

Abstract: The present invention relates to an improved fuel cell and method for controlling same having an anode and a cathode which produces an electrical current having a given voltage and current output and which includes a controller electrically coupled with the fuel cell and which shunts the electrical current between the anode and the cathode of the fuel cell. The invention also discloses a method for controlling the fuel cell having an anode, a cathode and a given voltage and current output and which includes determining the voltage and current output of the fuel cell; and shunting the electrical current between the anode and cathode of the fuel cell under first and second operational conditions.

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.