Cellex Power Products, Inc.

Plug Power Inc.

David A Leboe

Adrian James Corless

Kenneth William Kratschmar

Kenneth M Flaherty

Rasvan Catalin Mihai

John Douglas Usborne

A fuel cell-based system includes an electromechanical pressure relief system to prevent an overpressure condition from damaging the anode circuit of a fuel cell stack or creating a hazardous environment. Upon detection of a fuel flow pressure in a fuel path between a fuel source and the fuel cell stack, the pressure relief system isolates the anode circuit from the fuel path, vents the fuel flow, and shuts down the fuel cell system.

Pressure relief control system for a fuel cell system having a pressurized fuel flow

A technique includes providing fuel and oxidant flows to a fuel cell. The technique includes humidifying the anode of the fuel cell, including saturating the oxidant flow and maintaining a temperature of the oxidant flow above a temperature of the fuel cell such that excess water propagates from a cathode of the fuel cell to the anode.

Anode humidification

This application relates to a method and system for controlling the supply of fuel to a dead-ended hydrogen fuel cell. The invention may be utilized, for example, to more efficiently integrate the operation of a hydrogen fuel cell and a hydrogen generator, such as a reformer coupled with a hydrogen separation unit. The invention ensures that the production and consumption of hydrogen are effectively balanced to avoid negative feed line pressure fluctuations. The fuel supply control subsystem and hydrogen consumption control subsystems are, however, 'decoupled' and hence independently operable. The invention may include an accumulator disposed in a flow path between the hydrogen generator and the fuel cell for storing hydrogen under pressure. The accumulator is sufficiently large in volume such that the pressure of hydrogen in the flow path does not deviate substantially from a target pressure, even during the waste purging sessions. The system enables the use of low-cost pressure transducers in place of mass flow meters. In one aspect of the invention raffinate flow from the hydrogen separator can be controllably adjusted to regulate the temperature or other operating parameters of the reformer.

Method and system for controlling the operation of a hydrogen generator and a fuel cell

This application relates to a system and method for regulating the temperature of a self-contained fuel cell apparatus preferably comprising a fuel reformer. The invention maintains the various components of the fuel cell apparatus within preferred operating temperature ranges while ensuring that exhaust gases and external surfaces of the apparatus do not exceed safe temperature levels. The invention is particularly suited for self-contained hybrid power supply applications, for example for non-road electric vehicles. The various components of the apparatus are strategically configured relative to air flow paths to fully utilize the cooling capacity of the process stream and minimize parasitic loads. In some embodiments the inlet air is pre-heated to enable operation of the apparatus in low temperature environments, such as industrial freezers.

Fuel cell thermal management system and method

A system and method for improving the performance of a hybrid power supply apparatus comprising a power generating device, such as a fuel cell, and a primary energy storage device, such as a battery. The purpose of the invention is to provide an equalization charge to the battery from a source other than the fuel cell when the battery achieves a predetermined state of charge condition, thereby avoiding the need to operate the fuel cell in a low power output mode. When the predetermined state of charge condition is detected by a controller, the fuel cell is shut-down. In one aspect of the invention the equalization charge is provided to the battery by a secondary energy storage device, such as a plurality of capacitors or secondary batteries. The predetermined state of charge condition may be satisfied, for example, when the state of charge of the battery exceeds a predetermined threshold, such as 80% of the battery's storage capacity, for a predetermined period of time. In some aspects of the invention, the secondary energy storage device may also be connectable to the load. Preferably the system also includes a DC/DC converter for regulating current flow between the fuel cell and the storage devices.

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Vancouver, Canada

David A Leboe