Abstract:
Methods and system for enhancing the fuel economy of a diesel engine is disclosed. The system is useable in a four stroke diesel engine to allow a first injection step to be performed whereby fuel is injected into the cylinders of a diesel engine to initiate combustion of the fuel within the cylinder. A second injection step then occurs, whereby an additive is injected into the cylinder, during the cycle but at a time different than the first injection step wherein the additive reaches the cylinder wall. The additive, which reaches the cylinder wall, provides friction modification and fuel economy benefits for a diesel engine.
Abstract:
The present invention provides a protonically conductive membrane for use in a direct methanol fuel cell wherein a portion of said protonically conductive membrane conducts protons from the anode face of the membrane to the cathode face of the protonically conductive membrane, and a portion of which evolves gas from the anode side of the membrane to the cathode side of the protonically conductive membrane where it is vented to the environment. The present invention also includes a membrane electrode assembly, fuel cell and fuel cell system which are comprised of the protonically conductive membrane and which evolve gas from the anode side of the protonically conductive membrane to the cathode side of the protonically conductive membrane, where it is vented to the ambient environment.
Abstract:
A direct methanol fuel cell (DMFC) system in which, in response to changes in the output power level of the cell, the concentration of methanol supplied to the anode is actively regulated. As a result, cross-over of methanol through the cell's membrane electrolyte is minimized, and operating efficiency is maintained over a wide dynamic range of output power levels.
Abstract:
A fuel container and delivery assembly for use with a direct oxidation fuel cell system is provided. The container and delivery assembly allows clean fuel which, in a preferred embodiment, is in the form of either pure methanol or an aqueous methanol/water mixture to be delivered to the cell. Additives are mixed with the fuel containing substance prior to release of the fuel outside of the cell. The fuel substance is housed in an inner tank, which is disposed within an outer container. A plenum area defined by the space between the outer container and the flexible bladder is filled with the additives so that, upon rupture of the entire assembly, the fuel substance is mixed with the additives. In one embodiment of the invention, the inner tank is a flexible bladder. A rupture means is provided on a needle, which draws the fuel out in pure form, tears the flexible bladder so that any remaining fuel is mixed with the additives when it is desired to dispose of or re-fill the container.
Abstract:
An integrated system includes a fuel cell assembly for supplying electrical power to a building, a furnace having a heating chamber and a heat exchanger for supplying heat to the building, and a reformer for providing a supply of reformate directly to the furnace and the fuel cell assembly. The system may include a controller for apportioning the supply of reformate to the fuel cell assembly and to the furnace in response to heating and electrical power needs of the building. In another embodiment, an integrated system includes a fuel cell assembly for providing electrical power to a building, a reformer/furnace unit comprising a chamber and a heat exchanger for providing heat to a building, and wherein fuel is reformed/oxidized in a fuel-rich environment in said chamber to produce a supply of reformate for said fuel cell assembly, and in a fuel-lean environment in said chamber for releasing heat. The system may also include a controller for operating the chamber between a fuel-rich and a fuel-lean environment in response to heating and electrical power needs of the building.
Abstract:
A direct methanol fuel cell (DMFC) system is provided with a pump for pumping methanol into the cell. The pump is driven by carbon dioxide produced by the electrochemical reaction at the anode of the fuel cell. Because the amount of CO2 generated is proportional to the power generated by the cell, and thus the amount of fuel demanded by the cell, the pump is self-regulating. The system may be integrated using microelectromechanical system fabrication techniques.
Abstract:
A fluid flow plate includes a generally porous portion and a generally non-porous portion which together form on a first surface of the plate, a flow channel having at least one turn for distributing a reactant gas in a fuel cell. The porous portion defines an outer lateral portion of the at least one turn. Such fluid flow plate(s) provide a water management scheme for a fuel cell and/or fuel cell assembly in which the turn(s) in a flow channel of the fluid flow plate(s) are used for multi-point per flow channel addition, removal, and/or redistribution of water for regulation of the humidity of a stream of reactant gas for membrane hydration and/or cooling. Desirably, for removal of water, the inertia of large water droplets moving along with the reactant gas through the flow channel impact the porous portion which forms the outer lateral portion of the turn(s).
Abstract:
Apparatus and methods for regulating methanol concentration in a direct methanol fuel cell system without the need for a methanol concentration sensor. One or more operating characteristics of the fuel cell, such as the potential across the load, open circuit potential, potential at the anode proximate to the end of the fuel flow path or short circuit current of the fuel cell, are used to actively control the methanol concentration.
Abstract:
A direct methanol fuel cell (DMFC) system is provided with a pump for pumping methanol into the cell. The pump is driven by carbon dioxide produced by the electro-chemical reaction at the anode of the fuel cell. Because the amount of CO2 generated is proportional to the power generated by the cell, and thus the amount of fuel demanded by the cell, the pump is self-regulating. The system may be integrated using microelectro-mechanical system fabrication techniques.
Abstract:
A method and apparatus for oxygen management in a direct oxidation fuel cell system is provided. The oxygen management apparatus forces oxygen (typically from ambient air) into the cathode chamber of the fuel cell to facilitate the flow of oxygen across the cathode face of the fuel cell. It does so by utilizing the carbon dioxide already produced in the chemical reaction on the anode chamber of the cell. In a first embodiment of the invention, a turbine assembly is placed in fluid communication with the anode chamber of the fuel cell. The turbine assembly is driven when the carbon dioxide produced at the anode chamber flows over the blades of a first turbine (which is referred to herein as “the vent turbine”). The vent turbine is attached to a drive shaft that is used to cause a second turbine (or fan) to draw oxygen (generally from ambient air) into the cathode chamber of the fuel cell. This drawn-in air forces oxygen over the cathode of the fuel cell. The second turbine is referred to herein as “the inlet turbine.” Other embodiments of the invention allow for adjustments to be made depending upon the conditions in which the invention is used.