Abstract:
The invention relates to hybrid fuel cell systems that protect a fuel cell with a second electrical energy source. The second electrical energy source powers a load to prevent the fuel cell from witnessing stoichiometric levels that may lead to reductions in fuel cell performance or health. The hybrid fuel cell system includes an electrical circuit that electrically initiates the electrical energy source to provide power to the load in response to detecting a potential stoichiometric disturbance for the fuel cell.
Abstract:
Described herein is a portable storage device that stores a hydrogen fuel source. The storage device includes a bladder that contains the hydrogen fuel source and conforms to the volume of the hydrogen fuel source. A housing provides mechanical protection for the bladder. The storage device also includes a connector that interfaces with a mating connector to permit transfer of the fuel source between the bladder and a device that includes the mating connector. The device may be a portable electronics device such as a laptop computer. Refillable hydrogen fuel source storage devices and systems are also described. Hot swappable fuel storage systems described herein allow a portable hydrogen fuel source storage device to be removed from a fuel processor or electronics device it provides the hydrogen fuel source to, without shutting down the receiving device or without compromising hydrogen fuel source provision.
Abstract:
The invention relates to micro fuel cell systems whose performance is enhanced by an accurate fluid delivery system. The fluid delivery system improves reactant fluid provision to meet electrical output, while maintaining correct stoichiometries for chemical processing in a downstream reactor. The fluid delivery system includes a pressure source and a differential flow meter. The differential flow meter uses a flow restrictor and a sensor. The pressure source moves a fluid through the flow restrictor; the sensor detects differential pressure in the flow restrictor and outputs a signal that permits dynamic control of fluid flow, e.g., by controlling a pump.
Abstract:
Described herein is a portable storage device that stores a hydrogen fuel source. The storage device includes a bladder that contains the hydrogen fuel source and conforms to the volume of the hydrogen fuel source. A housing provides mechanical protection for the bladder. The storage device also includes a connector that interfaces with a mating connector to permit transfer of the fuel source between the bladder and a device that includes the mating connector. The device may be a portable electronics device such as a laptop computer. Refillable hydrogen fuel source storage devices and systems are also described. Hot swappable fuel storage systems described herein allow a portable hydrogen fuel source storage device to be removed from a fuel processor or electronics device it provides the hydrogen fuel source to, without shutting down the receiving device or without compromising hydrogen fuel source provision.
Abstract:
Described herein is a portable storage device that stores a hydrogen fuel source. The storage device includes a bladder that contains the hydrogen fuel source and conforms to the volume of the hydrogen fuel source. A housing provides mechanical protection for the bladder. The storage device also includes a connector that interfaces with a mating connector to permit transfer of the fuel source between the bladder and a device that includes the mating connector. The device may be a portable electronics device such as a laptop computer. Refillable hydrogen fuel source storage devices and systems are also described. Hot swappable fuel storage systems described herein allow a portable hydrogen fuel source storage device to be removed from a fuel processor or electronics device it provides the hydrogen fuel source to, without shutting down the receiving device or without compromising hydrogen fuel source provision.
Abstract:
Described herein are fuel cell systems and methods of using fuel cell systems. The systems include a fuel cell that generates electrical energy using hydrogen and a fuel processor that produces hydrogen from a fuel source. The fuel processor includes a reformer and a burner that heats the reformer. One heat efficient fuel cell system described herein heats internal portions of a fuel cell using a heating medium from a fuel processor. The heating medium may comprise gases exhausted at high temperatures from the fuel processor, which are then transported to the fuel cell. The heating medium may also include a gas that reacts catalytically in the fuel cell to produce heat. Systems and methods for expediting fuel cell system start up are provided. Methods for shutting down a fuel cell system are also described that reduce the amount of moisture and gases in the reformer and in one or more fuel cell components. One hydrogen efficient fuel cell system described herein transports hydrogen to an inlet of a burner. The hydrogen may comprise unused hydrogen from a fuel cell and/or hydrogen produced in a reformer. The burner comprises a catalyst that facilitates production of heat in the presence of the hydrogen.
Abstract:
Described herein is a fuel processor that produces hydrogen from a fuel source. The fuel processor comprises a reformer and burner. The reformer includes a catalyst that facilitates the production of hydrogen from the fuel source. Voluminous reformer chamber designs are provided that increase the amount of catalyst that can be used in a reformer and increase hydrogen output for a given fuel processor size. The burner provides heat to the reformer. One or more burners may be configured to surround a reformer on multiple sides to increase thermal transfer to the reformer. Dewars are also described that increase thermal management of a fuel processor and increase burner efficiency. A dewar includes one or more dewar chambers that receive inlet air before a burner receives the air. The dewar is arranged such that air passing through the dewar chamber intercepts heat generated in the burner before the heat escapes the fuel processor.
Abstract:
The invention relates to fuel cell systems with improved thermal efficiency. The systems include a fuel cell that generates electrical energy using hydrogen and a fuel processor that produces hydrogen from a fuel. Some heat efficient systems described herein include a thermal catalyst that generates heat when the catalyst interacts with a heating medium. The heat is used to heat the fuel cell. The thermal catalyst may be disposed in proximity to the fuel cell, or remote from the fuel cell and a heat transfer pipe conducts heat from the catalyst to the fuel cell. Another thermally efficient embodiment uses a recuperator to transfer heat generated in the fuel cell system to incoming fuel. A fuel cell package may also include a multi-layer insulation arrangement to decrease heat loss from the fuel cell and fuel processor, which both typically operate at elevated temperatures.
Abstract:
The present invention relates to fuel cells and components used within a fuel cell. Heat transfer appendages are described that improve fuel cell thermal management. Each heat transfer appendage is arranged on an external portion of a bi-polar plate and permits conductive heat transfer between inner portions of the bi-polar plate and outer portions of the bi-polar plate proximate to the appendage. The heat transfer appendage may be used for heating or cooling inner portions of a fuel cell stack. Improved thermal management provided by cooling the heat transfer appendages also permits new channel field designs that distribute the reactant gases to a membrane electrode assembly. Flow buffers are described that improve delivery of reactant gases and removal of reaction products. Single plate bi-polar plates may also include staggered channel designs that reduce the thickness of the single plate.
Abstract:
The invention relates to a compact and portable fuel cell package. The package includes a fuel cell that generates electrical energy. Some packages also include a fuel processor that produces hydrogen from a fuel source. Fuel cell packages described herein provide power densities (power per unit volume or mass) at levels not yet seen. One package employs an interconnect disposed at least partially between a fuel cell and a fuel processor. The interconnect forms a structural and plumbing intermediary between the two. Given the portable size of fuel cell packages described herein, the invention is well suited to power portable electronics devices. One portable fuel cell package includes a tether, which allows electrical and detachable coupling to an electronics device.