# US 12,015,180 B2 · Fuel cell valve configuration > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,015,180 B2 - Document ID: US12015180B2 - Status: Granted - Kind: B2 - Application number: 18/183,217 - Filed: 2023-03-14 - Published: 2023-07-13 - Granted: 2024-06-18 - Earliest claimed: 2019-12-17 - Assignees: Hyaxiom, Inc. - Applicants: Hyaxiom, Inc. - Inventors: James Kenney - Web page: https://patentgrep.com/patent/US12015180B2 ## CPC - H01M 8/04089: of gaseous reactants - H01M 8/04753: {of fuel cell reactants} - H01M 8/04208: {Cartridges, cryogenic media or cryogenic reservoirs} - H01M 8/04228: during shut-down - H01M 8/04231: {Purging of the reactants} - H01M 8/04955: Shut-off or shut-down of fuel cells - Y02E 60/50: Fuel cells - H01M: PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY - Y02E: REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION ## Abstract An illustrative example method of controlling operation of a fuel cell power plant includes opening a pneumatic valve using pneumatic pressure of pressurized fuel cell reactant, allowing the pressurized fuel cell reactant to flow through the pneumatic valve to a cell stack assembly, determining that shutdown of the cell stack assembly is desired, and control a rate that the pneumatic valve closes by controlling a rate of release of the pneumatic pressure. ## Claims ### Claim 1 A method of controlling operation of a fuel cell power plant, the method comprising: opening a pneumatic valve using pneumatic pressure of pressurized fluid including at least one of a reactant and a purge gas that differs from the reactant; allowing the pressurized fluid to flow through the pneumatic valve to a cell stack assembly in response to opening the pneumatic valve; determining that shutdown of the cell stack assembly is desired; and controlling a rate that the pneumatic valve closes by controlling a rate of release of the pneumatic pressure during a shutdown procedure of the cell stack assembly, including selectively reducing the pneumatic pressure to control a rate at which the pneumatic valve changes from an open condition to a closed condition, wherein the rate at which the pneumatic valve changes from the open condition to the closed condition allows at least some of the pressurized fluid including the purge gas to flow through the pneumatic valve during the shutdown procedure. ### Claim 2 (depends on 1) The method of claim 1, comprising delivering at least some of the pressurized fluid to a pressure reservoir; and using pressure in the pressure reservoir as the pneumatic pressure for opening the pneumatic valve. ### Claim 3 (depends on 2) The method of claim 2, comprising isolating the pressure reservoir from a source of the pressurized fluid in response to determining that shutdown of the cell stack assembly is desired; and venting the pressurized fluid from the pressure reservoir at a rate that controls the rate that the pneumatic valve closes. ### Claim 4 (depends on 1) The method of claim 1, comprising selectively allowing a pressure of the pressurized fluid to provide pneumatic pressure to maintain the pneumatic valve in the open condition. ### Claim 5 (depends on 1) The method of claim 1, comprising using a pressure reservoir for providing the pneumatic pressure. ### Claim 6 (depends on 5) The method of claim 5, wherein the pressure reservoir is coupled to an actuator of the pneumatic valve; the actuator of the pneumatic valve includes a piston that is biased in a first direction to urge the pneumatic valve into the closed condition; and the pneumatic pressure of the reservoir moves the piston in a second direction to urge the pneumatic valve into the open condition. ### Claim 7 (depends on 5) The method of claim 5, comprising operating a control valve in a first condition that allows the pressurized fluid to flow into the pressure reservoir and in a second condition that isolates the pressure reservoir from the pressurized fluid and vents pressurized fluid from the pressure reservoir. ### Claim 8 (depends on 7) The method of claim 7, comprising controlling the rate at which the pneumatic valve changes from the open condition to the closed condition by controlling a flow rate of the second condition of the control valve. ### Claim 9 (depends on 7) The method of claim 7, wherein the pneumatic valve is situated to control whether the pressurized fluid flows through a supply conduit to a fuel cell, and the control valve is coupled to a branch of the supply conduit upstream of the pneumatic valve. ### Claim 10 (depends on 1) The method of claim 1, wherein: the reactant comprises hydrogen. ### Claim 11 (depends on 1) The method of claim 1, wherein: the purge gas comprises nitrogen. ### Claim 12 (depends on 11) The method of claim 11, wherein: the reactant comprises hydrogen; and an amount of the nitrogen flows through the pneumatic valve to purge excess hydrogen from the cell stack assembly during the controlling step. ### Claim 13 (depends on 9) The method of claim 9, wherein: the control valve includes a first port, a second port and a third port; the control valve interconnects the first port to the second port but not the third port in the first condition to convey the pressurized fluid from the branch of the supply conduit to the pressure reservoir; and the control valve interconnects the second port and the third port but not the first port in the second condition to convey the pressurized fluid from the pressure reservoir through a discharge conduit to a vent. ### Claim 14 A method of controlling operation of a fuel cell power plant, the method comprising: opening a pneumatic valve using pneumatic pressure of pressurized fluid including at least one of a reactant and a purge gas that differs from the reactant, and the reactant comprises hydrogen; communicating the pressurized fluid including the reactant through the pneumatic valve to a plurality of fuel cells of a cell stack assembly in response to opening the pneumatic valve; and controlling a rate that the pneumatic valve closes by controlling a rate of release of the pneumatic pressure during a shutdown procedure of the cell stack assembly, including selectively reducing the pneumatic pressure to control a rate at which the pneumatic valve changes from an open condition to a closed condition such that at least some of the purge gas flows through the pneumatic valve to purge excess hydrogen from the cell stack assembly during the shutdown procedure. ### Claim 15 (depends on 14) The method of claim 14, comprising: using a pressure reservoir for providing the pneumatic pressure; isolating the pressure reservoir from a source of the pressurized fluid in response to determining that shutdown of the cell stack assembly is desired; and venting the pressurized fluid from the pressure reservoir at a rate that controls the rate that the pneumatic valve closes during the isolating step. ### Claim 16 (depends on 15) The method of claim 15, comprising: operating a three-way control valve in a first condition that allows the pressurized fluid to flow from a source into the pressure reservoir; and operating the three-way control valve in a second condition that vents the pressurized fluid from the pressure reservoir to a vent but isolates the pressure reservoir from the source. ### Claim 17 (depends on 14) The method of claim 14, wherein: the purge gas comprises nitrogen.