摘要:
Processes to shut down a fuel cell system are described. In one implementation (300), a load (215) is cyclically engaged and disengaged across a fuel cell stack (205) so as to deplete the fuel available to the system's fuel cells (205). Voltage and/or current thresholds may be used to determine when to engage and disengage the load (215) and when to terminate the shutdown operation. In another implementation (500), a variable load (405) is engaged and adjusted so as to deplete the fuel available to the system's fuel cells (205). As before, voltage and/or current thresholds may be used to determine when to adjust the load (405) and when to terminate the shutdown process. In still another implementation, a load (215 or 405) may be periodically engaged and disengaged during some portion of the shutdown process and engaged but adjusted during other portions of the shutdown process.
摘要:
A product includes a fuel cell stack, and an enclosure apparatus sealingly enclosing the fuel cell stack to define a hydrogen chamber between the fuel cell stack and the enclosure apparatus.
摘要:
A product includes a fuel cell stack, and an enclosure apparatus sealingly enclosing the fuel cell stack to define a hydrogen chamber between the fuel cell stack and the enclosure apparatus. An operation of the product may include maintaining a positive pressure of hydrogen in the hydrogen chamber.
摘要:
A method for reducing the probability of an air/hydrogen front in a fuel cell stack is disclosed that includes closing anode valves for an anode side of the fuel cell stack to permit a desired quantity of hydrogen to be left in the anode side upon shutdown and determining a schedule to inject hydrogen during the time the fuel cell stack is shutdown. The pressure on an anode input line is determined and a discrete amount of hydrogen is injected into the anode side of the stack according to the determined schedule by opening anode input line valves based on the determined pressure along the anode input line so as to inject the hydrogen into the anode side of the stack.
摘要:
A method for reducing the probability of an air/hydrogen front in a fuel cell stack is disclosed that includes closing anode valves for an anode side of the fuel cell stack to permit a desired quantity of hydrogen to be left in the anode side upon shutdown and determining a schedule to inject hydrogen during the time the fuel cell stack is shutdown. The pressure on an anode input line is determined and a discrete amount of hydrogen is injected into the anode side of the stack according to the determined schedule by opening anode input line valves based on the determined pressure along the anode input line so as to inject the hydrogen into the anode side of the stack.
摘要:
A method for creating an oxygen depleted gas in a fuel cell system, including operating a fuel cell stack at a desired cathode stoichiometry at fuel cell system shutdown to displace a cathode exhaust gas with an oxygen depleted gas. The method further includes closing a cathode flow valve and turning off a compressor to stop the flow of cathode air.
摘要:
A membrane humidifier for a fuel cell with a wet side plate having a plurality of flow channels formed therein and a dry side plate having a plurality of flow channels formed therein, the flow channels of the wet side plate adapted to facilitate a flow of a wet gas therethrough and the flow channels of said dry side plate adapted to facilitate a flow of a dry gas therethrough, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.
摘要:
A membrane humidifier for a fuel cell is disclosed, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.
摘要:
A membrane humidifier for a fuel cell is disclosed, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.
摘要:
A membrane humidifier for a fuel cell with a wet side plate having a plurality of flow channels formed therein and a dry side plate having a plurality of flow channels formed therein, the flow channels of the wet side plate adapted to facilitate a flow of a wet gas therethrough and the flow channels of said dry side plate adapted to facilitate a flow of a dry gas therethrough, wherein a pressure drop in the humidifier is minimized and a humidification of a proton exchange membrane in the fuel cell is optimized.