Daimler Ag

Ford Motor Company Limited

Ballard Power Systems Ag

Ballard Power Systems Corporation

Janusz Blaszczyk

Wolfram Fleck

Richard Fellows

Michael P Sexsmith

Michael Procter

Rainer W Schmidt

Colin F Keddie

Peter J Bach

Paul L Paterson

A fuel cell stack comprising a fuel inlet and an oxidant inlet for allowing the supply of a fuel and an oxidant to the fuel cell stack, respectively, and a fuel outlet and an oxidant outlet for allowing the removal of an anode exhaust and a cathode exhaust from the fuel cell stack, respectively, wherein the fuel outlet is fluidly connected to a high frequency purge valve.

System and method of purging fuel cell stacks

In a device for humidifying a gas flow, an atomized liquid is combined with a gas flow in a spray chamber, and passed through a generally U-shaped gas flow passage having a first generally vertical partthrough which the atomized liquid and gas passes to a lower part. From there, the gas passes generally vertically upwardly to an outlet. The lower part of the passage incorporates an openingto a water separator. The openingis closable by a float device, or includes a flow restricting control valve

Apparatus for humidifying a gas flow

A fuel cell system comprising a fuel cell stack, a fuel recirculation line provided with a jet pump and a valve controlled by a control unit based on the anode-cathode pressure differential such that the valve is closed to reduce or stop fuel supply when the anode-cathode pressure differential reaches a predetermined value, and opened again to circulate more fuel through the jet pump when the pressure differential is below a predetermined value, to create a pulsed fuel supply that improves the fuel recirculation at low loads and ensures adequate water removal from the anode flow field channels.

Fuel cell system with improved fuel recirculation

An apparatus for recirculating a reactant fluid stream of a fuel cell system, and electric power generation systems comprising the apparatus, are disclosed. The apparatus comprises (1) a common suction chamber fluidly connected to a suction inlet configured to receive a recirculated flow from the exhaust stream of the fuel cell stack, (2) a low-flow nozzle positioned in the common suction chamber and fluidly connected to a low-flow motive inlet configured to receive a first motive flow from a reactant source of the fuel cell stack, (3) a low-flow diffuser fluidly connected to a discharge outlet configured to provide the inlet stream to the fuel cell stack, (4) a high-flow nozzle positioned in the common suction chamber and fluidly connected to a high-flow motive inlet configured to receive the first motive flow from the reactant source, and (5) a high-flow diffuser fluidly connected to the discharge outlet.

Fuel cell system with fluid stream recirculation

A fuel cell system and associated method allows for continuous operation of the fuel cell system with fuel recirculation, without the necessity for periodic purging. A portion of the anode exhaust is not recirculated but is continuously bled from the anode exhaust line. Preferably, less than 5% by volume of the anode exhaust is allowed to bleed continuously from the anode exhaust. The bleed line may be connected to a catalytic reactor which combusts the unused fuel. The cathode exhaust may be used as the oxidant for the catalytic reactor. The flow of exhaust to the catalytic reactor may be controlled to ensure that the concentration of hydrogen in the catalytic reactor is no higher than 50% of the lower limit of inflammability for hydrogen.

Fuel cell system and method for operating the same

A method and apparatus for humidifying a gas flow includes means for atomizing a liquid into a gas feed line and means for heating the liquid. The atomizing means is provided in a spray chamber, with a heat-exchanger region for at least partially evaporating the liquid being arranged adjacent to the spray chamber. The heat-exchanger region has a multiplicity of flow passages for gas flows which are to be humidified, which flow passages are at least partially delimited by heat-exchanger surfaces for condensing and evaporating the liquid.

Growing community of inventors

Richmond, CA, United States of America

Janusz Blaszczyk