Systems and methods for processing hydrogen

Abstract

The present disclosure provides a fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof; a second channel comprising a second inlet and a second outlet, the second channel in fluid communication with the cathode.

Description

[Background technology]

[0001] cross reference This application claims priority to U.S. Patent Application No. 17 / 589,287, filed January 31, 2022, and U.S. Provisional Patent Application No. 63 / 234,137, filed August 17, 2021, each of which is incorporated by reference in its entirety for all purposes.

[0002] A fuel source can be used to power a variety of systems. The fuel source can have a specific energy that corresponds to the amount of energy that can be stored or extracted per unit mass of fuel. The fuel source can be supplied to a variety of systems to enable such systems to generate energy (e.g., electrical energy) and / or provide power (e.g., for mobility or transportation purposes). Summary of the Invention [Means for solving the problem]

[0003] Hydrogen can be utilized as a clean energy source to power a variety of systems. Hydrogen can provide distinct advantages over other types of fuels, such as diesel, gasoline, or jet fuel, which have a specific energy of about 45 megajoules per kilogram (MJ / kg) (heat), or lithium-ion batteries, which have a specific energy of about 0.95 MJ / kg (electricity). In contrast, hydrogen has a specific energy (heat) of over 140 MJ / kg. Thus, 1 kg of hydrogen can produce the same amount of energy as about 3 kg of gasoline or kerosene. Thus, hydrogen as a fuel source can help reduce the amount of fuel (by mass) required to produce an equivalent amount of energy as other conventional fuel sources. Additionally, systems that use hydrogen as a fuel source (e.g., as a combustion reactant) generally produce harmless or non-toxic by-products, such as water, with minimal or near-zero emissions of carbon dioxide and nitrous oxide, thereby reducing the environmental impact of various systems (e.g., vehicles) that use hydrogen as a fuel source.

[0004] It is recognized herein that conventional systems and methods for processing hydrogen and / or mixtures of hydrogen and nitrogen to generate electrical energy have various limitations. For example, commercially available fuel cells may exhibit a decrease in performance over time when processing feedstock materials that include hydrogen and other impurities (e.g., gases, such as ammonia and / or nitrogen). The hydrogen extracted from the hydrogen carrier may contain one or more other elements or compounds that may adversely affect the performance of the fuel cell (e.g., the efficiency of conversion of the feedstock material to electrical energy), and commercially available fuel cells require separation of the hydrogen from other materials before feeding the hydrogen to the fuel cell, which may be time-consuming and resource-intensive.

[0005] The present disclosure provides systems and methods that address at least the above-mentioned shortcomings of conventional systems for processing feedstock materials to generate electrical energy. The present application generally relates to systems and methods for processing feedstock materials (e.g., hydrogen and / or nitrogen) to generate energy (e.g., electrical energy). The energy may be used to power a system, such as a vehicle. In some embodiments, the vehicle may include a drone, a light vehicle, a heavy vehicle, or a watercraft. In some embodiments, the vehicle may be configured to be operated by a human or a computer. In some embodiments, the vehicle is autonomous or semi-autonomous. The feedstock material may include hydrogen and other elements or compounds. In some cases, the feedstock material may include a mixture of hydrogen and nitrogen. The feedstock material may or may not include other impurities. In some cases, the feedstock material may be filtered before being fed to the fuel cell. Such filtration may be used to remove carbon monoxide and / or ammonia from the feedstock material. Using the systems and methods of the present disclosure, a hydrogen mixture may be converted to electrical energy without the need for filtration or purification of the hydrogen mixture to remove nitrogen and / or ammonia.

[0006] In one aspect, the present disclosure provides a fuel cell for processing hydrogen to generate an electric current. The fuel cell may include an anode, a cathode, and a membrane between the anode and the cathode. In some embodiments, the anode may include an anode gas diffusion layer having one or more channels for directing a feed material to the anode to facilitate processing of the feed material to generate an electric current. In some embodiments, the one or more channels may include one or more surface features configured to (i) enhance diffusion and transport of the feed material through the anode gas diffusion layer and (ii) facilitate purging of a selected material from the anode gas diffusion layer. In some embodiments, the feed material may include hydrogen and / or nitrogen. In some embodiments, the selected material may include at least nitrogen. In some embodiments, the selected material may include one or more impurities or unconverted ammonia. In some embodiments, the one or more features are configured to direct a flow of nitrogen from the anode gas diffusion layer out of the fuel cell such that the nitrogen does not accumulate in the anode gas diffusion layer.

[0007] In some embodiments, processing the feed material may include dissociating one or more hydrogen molecules of the feed material into one or more protons and one or more electrons. In some embodiments, the anode gas diffusion layer may include a felt material, a foam material, a cloth material, or a paper material. In some embodiments, the felt, foam, cloth, or paper material may be a carbon-based material (e.g., carbon fiber).

[0008] In some embodiments, the one or more surface features may comprise one or more cuts or grooves on a surface of the one or more channels. In some embodiments, the one or more cuts or grooves may extend across a portion of a surface of the one or more channels. In some embodiments, the one or more cuts or grooves may comprise two or more cuts or grooves that are parallel to one another. In some embodiments, the one or more cuts or grooves may comprise two or more cuts or grooves that are perpendicular to one another. In some embodiments, the one or more cuts or grooves may comprise two or more cuts or grooves that are disposed at an angle to one another. The angle may range from 0 degrees to about 90 degrees. In some embodiments, the one or more cuts or grooves may comprise two or more cuts or grooves that intersect one another. In some embodiments, the one or more cuts or grooves may comprise two or more cuts or grooves that do not intersect. In some embodiments, the one or more surface features may comprise one or more cutouts or openings on a surface of the one or more channels. In some embodiments, the one or more cutouts or openings may extend across a portion of a surface of the one or more channels. In some embodiments, the one or more cutouts or openings may comprise two or more cutouts or openings that are parallel to one another. In some embodiments, the one or more cutouts or openings may comprise two or more cutouts or openings that are perpendicular to one another. In some embodiments, the one or more cutouts or openings may comprise two or more cutouts or openings that are disposed at an angle to one another. In some embodiments, the angle may range from 0 degrees to about 90 degrees. In some embodiments, the one or more cutouts or openings may comprise two or more cuts or grooves that intersect with one another. In some embodiments, the one or more cutouts or openings may comprise two or more non-intersecting cutouts or openings.In some embodiments, one feature of the one or more features has a depth in a range from about 0.01 millimeters (mm) to about 10 mm.

[0009] In some embodiments, the anode gas diffusion layer may comprise one or more layers. In some embodiments, the one or more layers may comprise two or more layers. In some embodiments, at least one layer of the two or more layers may comprise one or more surface features. In some embodiments, the one or more surface features may comprise (i) one or more cuts or grooves, or (ii) one or more cutouts or openings. In some embodiments, the two or more layers may comprise a first layer comprising a first set of surface features and a second layer comprising a second set of surface features. In some embodiments, the first set of features and the second set of features may comprise the same or similar sets of features. In some embodiments, the first set of features and the second set of features may comprise different sets of features having different shapes, sizes, arrangements, or orientations. In some embodiments, the first set of features and the second set of features may overlap or partially overlap. In some embodiments, the first set of features and the second set of features may not overlap or need not overlap.

[0010] In some embodiments, the cathode may comprise one or more airflow channels. In some embodiments, the cathode may comprise a cathode current collecting layer and a cathode gas diffusion layer. In some embodiments, the one or more airflow channels, or a subset thereof, may be configured to function as a current collecting layer. In some embodiments, the anode may further comprise an anode current collecting layer.

[0011] In another aspect, the present disclosure provides a fuel cell system. The fuel cell system may comprise a plurality of fuel cells disclosed herein disposed adjacent to each other or stacked on top of each other. The plurality of fuel cells may comprise fuel cells having an anode, a cathode, and an electrolyte disposed between the anode and the cathode. In some embodiments, the anode may comprise an anode gas diffusion layer having one or more channels for directing a feed material through the anode to facilitate processing of the feed material to generate an electric current. In some embodiments, the one or more channels may comprise one or more surface features configured to (i) enhance diffusion and transport of the feed material through the anode gas diffusion layer and (ii) facilitate purging of a select material from the anode gas diffusion layer. In some embodiments, the fuel cell system may comprise at least one ammonia reformer or reactor in fluid communication with the plurality of fuel cells. In some embodiments, the at least one ammonia reformer or reactor is configured to (i) generate the feed material and (ii) supply the feed material to the fuel cell. In some embodiments, the fuel cell system comprises a computer configured to operate the fuel cell and enable the fuel cell to purge nitrogen from the fuel cell while the fuel cell is generating electricity. In some embodiments, the computer is configured to operate the fuel cells to enable a continuous purge of nitrogen. In some embodiments, the fuel cell system further comprises one or more inlet ports configured to receive a feedstock material, the feedstock material having an ammonia concentration of less than parts per million (ppm). In some embodiments, the fuel cell system further comprises one or more outlet ports configured to direct unconverted hydrogen from the plurality of fuel cells to at least one ammonia reformer or reactor for combustion heating.

[0012] In some aspects, the disclosure provides a method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer being in fluid communication with a fuel cell, the fuel cell having an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, and a first channel having a first inlet and a first outlet, the first channel being in fluid communication with the anode, the first channel being configured to: (i) increase the hydrogen consumption rate of the fuel cell, or (ii) increase the output voltage of the fuel cell at the same hydrogen consumption rate, when the first continuous stream contacts the anode, compared to a comparable fuel cell without any features. and a second channel having a second inlet and a second outlet, the second channel being in fluid communication with a cathode; the first channel having a number of features, the one or more features comprising: (1) one or more cuts, (2) one or more cutouts, (3) one or more grooves, or (4) any combination thereof; the second channel having a second inlet and a second outlet, the second channel being in fluid communication with a cathode; the second channel comprising:

[0013] In some embodiments, the one or more features increase the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode, as compared to a comparable fuel cell without any features.

[0014] In some embodiments, the one or more forms increase the rate of hydrogen consumption by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0015] In some embodiments, the one or more forms increase the rate of hydrogen consumption by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0016] In some embodiments, the one or more features increase the output voltage at the same hydrogen consumption rate when the first continuous flow contacts the anode, as compared to a comparable fuel cell without any features.

[0017] In some embodiments, the one or more features increase the voltage by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0018] In some embodiments, the one or more forms increase the rate of hydrogen consumption by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0019] In some embodiments, one or more features continuously purge nitrogen from the fuel cell.

[0020] In some embodiments, nitrogen is continuously purged from the first channel by one or more features such that nitrogen accumulation is reduced within the first channel, thereby increasing the hydrogen consumption rate compared to a comparable fuel cell lacking any features.

[0021] In some embodiments, the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode is at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0022] In some embodiments, the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode is at most about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0023] In some embodiments, the method further includes intermittently decreasing the hydrogen consumption rate to purge at least one of hydrogen, nitrogen, or water.

[0024] In some embodiments, the method further includes reducing the hydrogen consumption rate and directing at least a portion of the first continuous stream to an ammonia reformer.

[0025] In some embodiments, the method further includes reducing a hydrogen consumption rate of the fuel cell to zero and directing at least a portion of the first continuous stream to an ammonia reformer.

[0026] In some embodiments, the method further includes combusting at least a portion of the first continuous stream directed to the ammonia reformer in one or more combustion exhausts of the one or more fired heaters, the one or more fired heaters in communication with the ammonia reformer to heat the ammonia reformer, and the one or more fired heaters in fluid communication with the fuel cell to receive at least a portion of the first continuous stream.

[0027] In some aspects, the disclosure provides a method for reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel with a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof, and a second channel with a second inlet and a second outlet. and a second channel in fluid communication with a cathode; directing a first continuous stream through a first inlet into the first channel such that hydrogen contacts the anode; directing a second continuous stream including oxygen through a second inlet into the second channel such that oxygen contacts the cathode; and reacting the hydrogen and oxygen using a fuel cell to generate electricity, wherein the fuel cell is configured to provide a ratio of fuel cell power output to a projected surface area of ​​the anode of at least about 0.05 W / cm2, and wherein the first continuous stream includes about 25 mol % nitrogen and about 75 mol % hydrogen and the second continuous stream includes at least 20 mol % oxygen.

[0028] In some embodiments, the ratio is at least about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm2.

[0029] In some embodiments, the ratio is at most about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm2.

[0030] In some embodiments, the ratio is based on a first continuous flow comprising a hydrogen flow rate of at least about 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, or 100000 moles / second.

[0031] In some embodiments, the ratio is based on a second continuous flow comprising an oxygen flow rate of at least about 0.0001, 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000, 1000000 moles / second.

[0032] In some embodiments, the ratio is based on a second continuous flow that includes air.

[0033] In some embodiments, the ratio is based on a first continuous stream comprising hydrogen and nitrogen from an ammonia reformer.

[0034] In some embodiments, the anode projected surface area comprises the maximum possible surface area of ​​the anode projected onto a plane.

[0035] In some embodiments, the anode projected surface area includes the surface area of ​​the largest surface of the anode.

[0036] In some aspects, the disclosure provides a method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel having a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof; and a second channel comprising an electrolyte, the first channel comprising an electrolyte, the electrolyte being in fluid communication with the anode, the first channel comprising one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof. a second channel having an inlet and a second outlet, the second channel in fluid communication with the cathode; directing the first continuous stream into the first channel via the first inlet such that the hydrogen contacts the anode; directing a second continuous stream containing oxygen into the second channel via the second inlet such that the oxygen contacts the cathode; and reacting the hydrogen and oxygen using a fuel cell to generate power that is at least 50% of a reference power, wherein the reference power is generated using a fuel cell that receives a stream containing at least 99 mole % hydrogen into the first inlet, and the power is generated at the same current or at the same hydrogen consumption rate as the reference power.

[0037] In some embodiments, the power is at least 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0038] In some embodiments, the power is up to 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0039] In some aspects, the disclosure provides a method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel having a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cut-outs, (iii) one or more recesses, (iv) one or more recesses, (v) one or more recesses, (vi) one or more recesses, (vii) one or more recesses, (v ... a first channel having a plurality of grooves, or (iv) any combination thereof, wherein one or more features have a depth of less than 10 mm; and a second channel having a second inlet and a second outlet, the second channel in fluid communication with a cathode, the second channel comprising: (a) a first channel having a plurality of grooves, or (b) a second channel having a second inlet and a second outlet, the second channel in fluid communication with a cathode;

[0040] In some embodiments, the one or more features have a depth of less than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0041] In some embodiments, the one or more features have a depth of greater than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0042] In some embodiments, the depth is at least 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the first channel.

[0043] In some embodiments, the depth is up to 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the first channel.

[0044] In some embodiments, the first channel comprises a ratio of a first projected surface area of ​​the one or more features to a second projected surface area of ​​the first channel that is at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0045] In some embodiments, the first channel comprises a ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel that is at most 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0046] In some embodiments, the one or more features comprise two or more features.

[0047] In some embodiments, at least a first segment of a first feature of the two or more features is substantially parallel to a second segment of a second feature of the two or more features.

[0048] In some embodiments, at least a first segment of a first feature of the two or more features is substantially perpendicular to a second segment of a second feature of the two or more features.

[0049] In some embodiments, at least a first segment of a first feature of the two or more features is at an angle to a second segment of a second feature of the two or more features, the angle being between 0 and 90 degrees, between 15 and 75 degrees, between 0 and 30 degrees, or between 30 and 60 degrees.

[0050] In some embodiments, two or more features are linked.

[0051] In some embodiments, two or more features are separated.

[0052] In some embodiments, two or more features intersect.

[0053] In some embodiments, the one or more features comprise a serpentine shape.

[0054] In some embodiments, the one or more features are substantially parallel to the longest side of the first channel.

[0055] In some embodiments, the one or more features are substantially parallel to the shortest side of the first channel.

[0056] In some embodiments, the fuel cell comprises a plurality of channels in fluid communication with the anode, the plurality of channels comprising a first channel.

[0057] In some embodiments, the multiple channels comprise a stack of layers adjacent to one another.

[0058] In some embodiments, at least one channel of the plurality of channels does not include or is completely devoid of features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof.

[0059] In some embodiments, the one or more features are further configured to facilitate purging a select material from the anode gas diffusion layer, the select material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0060] In some embodiments, the fuel cell further comprises one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0061] In some embodiments, the first channel comprises a felt, foam, cloth, or paper material.

[0062] In some embodiments, the felt, foam, cloth, or paper material is a carbon-based material.

[0063] In some embodiments, the one or more features extend across at least a portion of a surface of the first channel.

[0064] In some embodiments, the electrolyte comprises a proton exchange membrane.

[0065] In some embodiments, the one or more features are configured to purge nitrogen from the fuel cell while the fuel cell is generating electricity.

[0066] In some embodiments, the ammonia concentration in the first continuous stream is up to 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0067] In some embodiments, the ammonia concentration in the first continuous stream is at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0068] In some embodiments, the one or more features increase the power density of the fuel cell by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0069] In some embodiments, the power density of the fuel cell is at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0070] In some embodiments, the power density of the fuel cell is at most about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0071] In some embodiments, the method further comprises discharging a third continuous stream comprising unconverted hydrogen from the fuel cell.

[0072] In some embodiments, the method further comprises directing a third continuous stream comprising unconverted hydrogen to an ammonia reformer.

[0073] In some embodiments, the method further includes combusting the unconverted hydrogen to heat the ammonia reformer.

[0074] In some embodiments, the method further includes using one or more air supply units to supply at least oxygen to the ammonia reformer to combust unconverted hydrogen in the third continuous stream.

[0075] In some embodiments, the method further comprises removing water in the third continuous stream prior to combusting the unconverted hydrogen.

[0076] In some embodiments, the method further comprises combusting the third continuous stream.

[0077] In some embodiments, the first continuous stream comprises up to about 50, 60, 70, 80, 90, 95, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, or 99.9 mole percent hydrogen.

[0078] In some embodiments, the first continuous stream comprises at least about 50, 60, 70, 80, 90, 95, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, or 99.9 mole percent hydrogen.

[0079] In some embodiments, the absolute pressure of the first continuous flow is at least about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar.

[0080] In some embodiments, the absolute pressure of the first continuous flow is at most about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar.

[0081] In some embodiments, the method further includes maintaining the absolute pressure of the first continuous flow within a tolerance of 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 150, 200, 300, 400, 500, or 1000% of the absolute pressure.

[0082] In some embodiments, the method further includes adjusting the absolute pressure of the first continuous flow using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0083] In some embodiments, one or more flow regulators, pressure regulators, control units, or any combination thereof are located upstream or downstream of the fuel cell.

[0084] In some embodiments, the method further includes regulating a flow rate of the third continuous stream using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0085] In some embodiments, one or more flow regulators, pressure regulators, control units, or any combination thereof are located upstream or downstream of the fuel cell.

[0086] In some embodiments, one or more flow regulators, pressure regulators, control units, or any combination thereof are positioned downstream of the fuel cell to prevent backflow of unconverted hydrogen.

[0087] In some embodiments, the method further includes powering one or more electrical devices using the generated electrical power.

[0088] In some embodiments, the method further includes using the generated power to power one or more electrical grids.

[0089] In some embodiments, the fuel cell comprises a plurality of fuel cells, and the ammonia reformer supplies a plurality of streams comprising hydrogen and nitrogen to the plurality of fuel cells.

[0090] In some embodiments, the method further includes directing unconverted hydrogen from the plurality of fuel cells to at least one ammonia reformer or reactor for combustion heating.

[0091] In some embodiments, at least one fuel cell of the plurality of fuel cells outputs a different power than other fuel cells of the plurality of fuel cells.

[0092] In some embodiments, at least one fuel cell of the plurality of fuel cells is configured to reduce its power output.

[0093] In some embodiments, the method further includes regulating the flow rates of the plurality of streams using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0094] In some embodiments, at least one fuel cell of the plurality of fuel cells receives one of the plurality of streams, the one stream having a flow rate that is different from the flow rates of other streams of the plurality of streams.

[0095] In some embodiments, each of the plurality of fuel cells receives one of the plurality of streams at a flow rate that is approximately the same as, or within a selected tolerance of, the other flow rates of the other streams of the plurality of streams.

[0096] In some embodiments, the selected tolerance range is about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%.

[0097] In some embodiments, the plurality of fuel cells comprises at least one fuel cell that differs from the other fuel cells in size, power output, hydrogen consumption rate, power density, or operating temperature.

[0098] In some aspects, the disclosure provides a system comprising an ammonia reformer configured to react ammonia to produce a first continuous stream comprising nitrogen and hydrogen; and a fuel cell in fluid communication with the ammonia reformer, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel comprising one or more features configured to (i) increase the hydrogen consumption rate when the first continuous stream contacts the anode or (ii) increase the output voltage at the same hydrogen consumption rate compared to a comparable fuel cell lacking any of the features, the one or more features being configured to include (i) one or more cuts, (ii) one or more cutouts, (i (ii) one or more grooves, or (iv) any combination thereof; and a second channel with a second inlet and a second outlet, the second channel in fluid communication with a cathode; and a controller comprising at least one processor configured to execute executable instructions, the instructions executable by the controller configured to: react ammonia using an ammonia reformer to produce a first continuous stream comprising hydrogen and nitrogen; direct a second continuous stream comprising oxygen to the cathode of the fuel cell; and direct the first continuous stream to an anode of the fuel cell to react the hydrogen and oxygen to generate electricity.

[0099] In some embodiments, the one or more features increase the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode, as compared to a comparable fuel cell without any features.

[0100] In some embodiments, the one or more forms increase the rate of hydrogen consumption by at least 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0101] In some embodiments, the one or more forms increase the rate of hydrogen consumption by up to 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0102] In some embodiments, the one or more features increase the output voltage at the same hydrogen consumption rate when the first continuous flow contacts the anode, as compared to a comparable fuel cell without any features.

[0103] In some embodiments, the one or more features increase the output voltage by at least 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200% at the same hydrogen consumption rate.

[0104] In some embodiments, the one or more forms increase the rate of hydrogen consumption by up to 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0105] In some embodiments, one or more features continuously purge nitrogen from the fuel cell.

[0106] In some embodiments, nitrogen is continuously directed out of the first channel by one or more features such that nitrogen accumulation is reduced within the first channel, thereby increasing the hydrogen consumption rate compared to a comparable fuel cell lacking any features.

[0107] In some embodiments, the hydrogen consumption rate of the fuel cell when the first continuous stream is in contact with the anode is at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0108] In some embodiments, the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode is at most about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0109] In some embodiments, the instructions executable by the controller are further configured to intermittently reduce the rate of hydrogen consumption to purge at least one of hydrogen, nitrogen, or water.

[0110] In some embodiments, the instructions executable by the controller are further configured to reduce a hydrogen consumption rate and direct at least a portion of the first continuous stream to an ammonia reformer.

[0111] In some embodiments, the instructions executable by the controller are further configured to reduce a hydrogen consumption rate of the fuel cell to zero and direct at least a portion of the first continuous stream to an ammonia reformer.

[0112] In some embodiments, the instructions executable by the controller are further configured to combust at least a portion of the first continuous stream directed to the ammonia reformer in one or more combustion exhausts of the one or more fired heaters, the one or more fired heaters in communication with the ammonia reformer to heat the ammonia reformer, the one or more fired heaters in fluid communication with a fuel to receive at least a portion of the first continuous stream.

[0113] In some aspects, the disclosure provides a fuel cell comprising: an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof; and a second channel comprising a second inlet and a second outlet, the second channel in fluid communication with the cathode, the fuel cell configured to obtain a ratio of fuel cell power output to a projected surface area of ​​the anode of at least about 0.05 W / cm2, the first inlet being supplied with a first continuous stream comprising about 25 mol % nitrogen and about 75 mol % hydrogen, and the second inlet being supplied with a second continuous stream comprising at least 20 mol % oxygen.

[0114] In some embodiments, the ratio is at least about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm2.

[0115] In some embodiments, the ratio is at most about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm2.

[0116] In some embodiments, the ratio is based on a first continuous flow comprising a hydrogen flow rate of at least about 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000 moles / second.

[0117] In some embodiments, the ratio is based on a second continuous flow comprising an oxygen flow rate of at least about 0.0001, 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000, 1000000 moles / second.

[0118] In some embodiments, the ratio is based on a second continuous flow that includes air.

[0119] In some embodiments, the ratio is based on a first continuous stream comprising hydrogen and nitrogen from an ammonia reformer.

[0120] In some embodiments, the projected surface area of ​​the anode comprises the maximum possible surface area of ​​the anode projected onto a plane.

[0121] In some embodiments, the projected surface area of ​​the anode includes the surface area of ​​the largest surface of the anode.

[0122] In some aspects, the disclosure provides a fuel cell comprising: an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features; and a second channel comprising a second inlet and a second outlet, the second channel in fluid communication with the cathode; the fuel cell in fluid communication with an ammonia reformer configured to supply nitrogen and hydrogen to the fuel cell; the fuel cell configured to generate power that is at least 80% of a reference power, the reference power being generated using the fuel cell receiving into the first inlet a continuous flow comprising at least 99 mole % hydrogen, and the power being generated at the same current or at the same hydrogen consumption rate as the reference power.

[0123] In some embodiments, the power is at least 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0124] In some embodiments, the power is up to 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0125] In some aspects, the disclosure provides a system, comprising: an ammonia reformer; and a fuel cell in fluid communication with the ammonia reformer, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; and a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof, wherein the one or more features comprises a depth of less than 10 mm. and a second channel having a second inlet and a second outlet, the second channel in fluid communication with the cathode; and a controller comprising at least one processor configured to execute executable instructions, the instructions executable by the controller configured to: direct the ammonia to an ammonia reformer to produce a first continuous stream comprising hydrogen and nitrogen; direct the second continuous stream comprising oxygen to the cathode of the fuel cell; and direct the first continuous stream to an anode of the fuel cell to react the hydrogen and oxygen to generate electricity.

[0126] In some embodiments, the one or more features have a depth of less than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0127] In some embodiments, the one or more features have a depth of greater than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0128] In some embodiments, the depth is at least 1 / 32, 1 / 16, 1 / 8, 1 / 4, or 1 / 2 the thickness of the first channel.

[0129] In some embodiments, the depth is at most 1 / 32, 1 / 16, 1 / 8, 1 / 4, or 1 / 2 the thickness of the first channel.

[0130] In some embodiments, the ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel is at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0131] In some embodiments, a ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel is at most 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0132] In some embodiments, the ammonia reformer produces a first continuous stream further comprising up to 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm ammonia.

[0133] In some embodiments, the ammonia reformer produces a first continuous stream further comprising at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm ammonia.

[0134] In some embodiments, the one or more features comprise two or more features.

[0135] In some embodiments, at least a first segment of a first feature of the two or more features is substantially parallel to a second segment of a second feature of the two or more features.

[0136] In some embodiments, at least a first segment of a first feature of the two or more features is substantially perpendicular to a second segment of a second feature of the two or more features.

[0137] In some embodiments, at least a first segment of a first feature of the two or more features is at an angle to a second segment of a second feature of the two or more features, the angle being between 0 and 90 degrees, between 15 and 75 degrees, between 0 and 30 degrees, or between 30 and 60 degrees.

[0138] In some embodiments, two or more features are linked.

[0139] In some embodiments, two or more features are separated.

[0140] In some embodiments, two or more features intersect.

[0141] In some embodiments, the one or more features are completely surrounded by the first channel.

[0142] In some embodiments, the one or more features are partially surrounded by the first channel.

[0143] In some embodiments, the one or more features comprise a serpentine shape.

[0144] In some embodiments, the one or more features are substantially parallel to the longest side of the first channel.

[0145] In some embodiments, the one or more features are substantially parallel to the shortest side of the first channel.

[0146] In some embodiments, the fuel cell comprises a plurality of channels in fluid communication with the anode, the plurality of channels comprising a first channel.

[0147] In some embodiments, the multiple channels comprise a stack of layers adjacent to one another.

[0148] In some embodiments, at least one channel of the plurality of channels does not include or is completely devoid of features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof.

[0149] In some embodiments, the one or more features are further configured to facilitate purging a select material from the anode gas diffusion layer, the select material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0150] In some embodiments, the fuel cell further comprises one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0151] In some embodiments, the first channel comprises a felt, foam, cloth, or paper material.

[0152] In some embodiments, the felt, foam, cloth, or paper material is a carbon-based material.

[0153] In some embodiments, the one or more features extend across at least a portion of a surface of the first channel.

[0154] In some embodiments, the electrolyte comprises a proton exchange membrane.

[0155] In some embodiments, the fuel cell is configured to allow nitrogen to be purged from the fuel cell while the fuel cell is generating electricity.

[0156] In some embodiments, the first channel is supplied with a stream comprising ammonia at a concentration of up to 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0157] In some embodiments, the first channel is supplied with a stream comprising ammonia at a concentration of at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0158] In some embodiments, the one or more features increase the power density of the fuel cell by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0159] In some embodiments, the power density of the fuel cell is at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0160] In some embodiments, the power density of the fuel cell is at most about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0161] In some embodiments, the system or fuel cell further comprises one or more fired heaters for combusting an outlet stream output by the fuel cell to heat the ammonia reformer, the outlet stream comprising unconverted hydrogen.

[0162] In some embodiments, the system or fuel cell further comprises one or more air supply units for supplying at least oxygen to the one or more fired heaters.

[0163] In some embodiments, the system or fuel cell further comprises one or more dehydration devices to remove water in the exit stream prior to combusting the unconverted hydrogen.

[0164] In some embodiments, the system is configured to combust unconverted hydrogen in the flue gas exhaust of one or more fired heaters.

[0165] In some embodiments, the system or fuel cell further comprises one or more flow regulators, pressure regulators, control units, or any combination thereof to adjust the absolute pressure of the input or exhaust streams of the fuel cell.

[0166] In some embodiments, one or more flow regulators, pressure regulators, control units, or any combination thereof are located upstream or downstream of the fuel cell.

[0167] In some embodiments, one or more flow regulators, pressure regulators, control units, or any combination thereof are positioned downstream of the fuel cell to reduce or prevent backflow of unconverted hydrogen.

[0168] In some embodiments, the system or fuel cell further comprises an electrical load that connects to the electrochemical circuit.

[0169] In some embodiments, the electrical load includes one or more electrical devices.

[0170] In some embodiments, the electrical load includes one or more power grids.

[0171] In some embodiments, the electrical load includes an engine or motor.

[0172] In some embodiments, the fuel cell comprises a plurality of fuel cells in conjunction with an ammonia reformer, the ammonia reformer configured to supply a plurality of streams comprising hydrogen and nitrogen to the plurality of fuel cells.

[0173] In some embodiments, the system is configured to direct unconverted hydrogen from the multiple fuel cells to one or more combustors in thermal communication with the ammonia reformer.

[0174] In some embodiments, at least one fuel cell of the plurality of fuel cells has a different power output than other fuel cells of the plurality of fuel cells.

[0175] In some embodiments, at least one fuel cell of the plurality of fuel cells is configured to reduce its power output.

[0176] In some embodiments, one or more ammonia reformers in fluid communication with the plurality of fuel cells supply a stream to at least one of the plurality of fuel cells with a flow rate that differs from the flow rates of other streams supplied to other fuel cells.

[0177] In some embodiments, one or more ammonia reformers in fluid communication with the plurality of fuel cells are configured to supply a plurality of streams to the plurality of fuel cells, wherein a flow rate of the plurality of streams is approximately the same as or within a selected tolerance range of other flow rates of other streams of the plurality of streams.

[0178] In some embodiments, the selected tolerance range is about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%.

[0179] In some embodiments, the plurality of fuel cells comprises at least one fuel cell that differs from the other fuel cells in size, power output, hydrogen consumption rate, power density, or operating temperature.

[0180] In some aspects, the disclosure provides a fuel cell comprising an anode, a cathode, and a membrane between the anode and the cathode, the anode comprising an anode gas diffusion layer comprising one or more channels for directing a feed material comprising hydrogen and nitrogen to the anode for processing the feed material to generate an electric current, the one or more channels comprising one or more features comprising (i) one or more cuts, (ii) one or more cutouts, or (iii) one or more grooves configured to enhance diffusion and transport of the feed material through the anode gas diffusion layer, the one or more features configured to direct a flow of nitrogen from the anode gas diffusion layer out of the fuel cell such that nitrogen does not accumulate in the anode gas diffusion layer.

[0181] In some embodiments, the one or more features comprise two or more features.

[0182] In some embodiments, the one or more features are further configured to facilitate purging a select material from the anode gas diffusion layer, the select material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0183] In some embodiments, the fuel cell further comprises one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0184] In some embodiments, processing the source material includes dissociating one or more hydrogen molecules of the source material into one or more protons and one or more electrons.

[0185] In some embodiments, the anode gas diffusion layer may comprise a felt, foam, cloth, or paper material.

[0186] In some embodiments, the felt, foam, cloth, or paper material is a carbon-based material.

[0187] In some embodiments, the one or more features extend across at least a portion of a surface of the one or more channels.

[0188] In some embodiments, two or more features are parallel to one another.

[0189] In some embodiments, two or more features are perpendicular to one another.

[0190] In some embodiments, two or more features are disposed at an angle relative to one another, the angle ranging from 0 degrees to 90 degrees.

[0191] In some embodiments, two or more features intersect one another.

[0192] In some embodiments, the two or more features do not intersect.

[0193] In some embodiments, the anode gas diffusion layer comprises multiple layers.

[0194] In some embodiments, at least one layer of the plurality of layers comprises one or more channels that comprise one or more features.

[0195] In some embodiments, the plurality of layers comprises a first layer comprising a first set of features and a second layer comprising a second set of features.

[0196] In some embodiments, the first set of features and the second set of features comprise the same or similar sets of features.

[0197] In some embodiments, the first set of features and the second set of features comprise different sets of features having different shapes, sizes, arrangements, or orientations.

[0198] In some embodiments, the first set of features and the second set of features overlap or partially overlap.

[0199] In some embodiments, the first set of features and the second set of features are non-overlapping.

[0200] In some embodiments, at least one feature of the one or more features has a depth in a range from about 0.01 millimeters (mm) to about 10 mm.

[0201] In some aspects, the present disclosure provides a fuel cell system comprising a plurality of fuel cells comprising a fuel cell as disclosed herein; and at least one ammonia reformer or reactor in fluid communication with the plurality of fuel cells, wherein the at least one ammonia reformer or reactor is configured to (i) produce a feedstock material and (ii) supply the feedstock material to the fuel cells.

[0202] In some embodiments, multiple fuel cells are arranged (i) adjacent to one another in a horizontal configuration, or (ii) on top of one another in a stacked configuration.

[0203] In some embodiments, the plurality of fuel cells comprises at least one proton exchange membrane fuel cell (PEMFC).

[0204] In some aspects, the present disclosure provides a fuel cell system comprising a fuel cell disclosed herein, the fuel cell system comprising a controller configured to operate the fuel cell and enable purging of nitrogen from the fuel cell while the fuel cell is generating electricity.

[0205] In some embodiments, the fuel cell system comprises a controller configured to operate the fuel cell and enable purging of nitrogen from the fuel cell while the fuel cell is generating electricity.

[0206] In some embodiments, at least one feature of the one or more features has a depth in a range from about 0.01 millimeters (mm) to about 10 mm.

[0207] In some embodiments, the fuel cell system further comprises one or more inlet ports configured to receive a feedstock material, the feedstock material having an ammonia concentration of less than 1 ppm.

[0208] In some embodiments, the fuel cell system further comprises one or more outlet ports configured to direct unconverted hydrogen from the plurality of fuel cells to at least one ammonia reformer or reactor, where the unconverted hydrogen is combusted to heat the ammonia reformer or reactor.

[0209] Another aspect of the present disclosure provides a non-transitory computer-readable medium containing machine-executable code that, when executed by one or more computer processors, performs any of the methods described above or elsewhere herein.

[0210] Another aspect of the present disclosure provides a system comprising one or more computer processors and a computer memory coupled thereto, the computer memory including machine executable code that, when executed by the one or more computer processors, performs any of the methods described above or elsewhere herein.

[0211] Other aspects and advantages of the present disclosure will become readily apparent to those skilled in the art from the following detailed description, in which only exemplary embodiments of the present disclosure have been shown and described. As will be understood, the present disclosure is capable of other and different embodiments, and its several details are capable of modification in various obvious respects, all without departing from the present disclosure. Accordingly, the drawings and description should be regarded as illustrative in nature, and not as restrictive.

[0212] Incorporation by Reference All publications, patents, and patent applications mentioned in this specification are herein incorporated by reference to the same extent as if each individual publication, patent, or patent application was specifically and individually indicated to be incorporated by reference. To the extent that the publications and patents or patent applications incorporated by reference conflict with the disclosure contained in the specification, the specification supersedes and / or takes precedence over any such conflicting content.

[0213] The patent or application file contains at least one drawing executed in color. Copies of this patent or patent application publication with color drawing(s) will be provided by the U.S. Patent and Trademark Office upon request and payment of the necessary fee.

[0214] The novel features of the invention are set forth with particularity in the appended claims. The features and advantages of the present invention will be better understood by reference to the following detailed description that sets forth illustrative embodiments, in which the principles of the invention are utilized, and the accompanying drawings (also referred to herein as "figures"), in which: [Brief description of the drawings]

[0215] [Figure 1] FIG. 1 illustrates a schematic of a fuel cell system according to some embodiments.

[0216] [Diagram 2] 2A-2B illustrate a schematic of H2 / N2 diffusion in a gas diffusion layer of a conventional fuel cell.

[0217] [Diagram 3] FIG. 3 illustrates a schematic illustrating improved performance of an anode channel with one or more cuts, according to some embodiments.

[0218] [Figure 4] FIG. 4 illustrates a schematic illustrating improved performance of an anode channel with one or more cutouts, according to some embodiments.

[0219] [Diagram 5] FIG. 5 illustrates generally the performance improvement of an anode channel with various multi-layer structures according to some embodiments.

[0220] [Figure 6] FIG. 6 illustrates a schematic of a fuel cell stack comprising multiple fuel cells, according to some embodiments.

[0221] [Figure 7] FIG. 7 illustrates a schematic of durability test results of a fuel cell stack having a multi-layer gas diffusion layer structure when nitrogen is present in the hydrogen gas mixture (volume ratio of hydrogen to nitrogen is 3:1) according to some embodiments.

[0222] [Figure 8] FIG. 8 illustrates a schematic diagram of durability test results of a fuel cell stack having a multi-layer gas diffusion layer structure with a gas mixture flow of hydrogen and nitrogen produced from an ammonia reforming process according to some embodiments.

[0223] [Figure 9] FIG. 9 illustrates generally a system for processing a feed material comprising hydrogen and nitrogen, according to some embodiments.

[0224] [Figure 10] FIG. 10 illustrates a schematic of a process for supplying a reformate gas to a fuel cell, according to some embodiments.

[0225]

[0226] [Figure 11] FIG. 11 illustrates generally various examples of cut structures that can be utilized in the anode channel of a fuel cell, according to some embodiments.

[0227] [Figure 12]FIG. 12 illustrates generally various examples of cutout structures that can be utilized in the anode channel of a fuel cell, according to some embodiments.

[0228] [Figure 13] FIG. 13 illustrates generally various examples of multi-layer anode channel structures, according to some embodiments.

[0229] [Figure 14] FIG. 14 illustrates generally a computer system that may be programmed or configured to carry out the methods provided herein.

[0230] [Figure 15] FIG. 15 illustrates the energy density of ammonia compared to other fuels, according to some embodiments. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0231] While various embodiments of the present invention have been shown and described herein, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the invention. It will be appreciated that various alternatives to the embodiments of the invention described herein may be employed.

[0232] Whenever the terms "at least," "greater than," or "greater than or equal to" appear after the last number in a series of two or more numbers, the terms "at least," "greater than," or "greater than or equal to" always apply to every number in the series. For example, 1, 2, or 3 or more is equivalent to 1 or more, 2 or more, or 3 or more.

[0233] When the term "less than", "less than" or "less than" appears after the last number in a series of two or more numbers, the term "less than", "less than" or "less than" applies to each number in the series. For example, 3, 2, or 1 or less is equivalent to 3 or less, 2 or less, or 1 or less.

[0234] The terms "real-time" or "real-time," as used interchangeably herein, generally refer to an event (e.g., an operation, process, method, technique, calculation, computation, analysis, visualization, optimization, etc.) that is performed using recently obtained (e.g., collected or received) data. In some cases, a real-time event may occur nearly instantly or within a sufficiently short time period, for example, within at least 0.0001 milliseconds (ms), 0.0005 ms, 0.001 ms, 0.005 ms, 0.01 ms, 0.05 ms, 0.1 ms, 0.5 ms, 1 ms, 5 ms, 0.01 seconds, 0.05 seconds, 0.1 seconds, 0.5 seconds, 1 second, or more. In some cases, a real-time event may be executed almost instantly or within a sufficiently short time, for example, within up to 1 second, 0.5 seconds, 0.1 seconds, 0.05 seconds, 0.01 seconds, 5 ms, 1 ms, 0.5 ms, 0.1 ms, 0.05 ms, 0.01 ms, 0.005 ms, 0.001 ms, 0.0005 ms, 0.0001 ms, or less.

[0235] The terms "at least one of A and B" and "at least one of A or B" can be understood to mean A only, B only, or both A and B. The term "A and / or B" can be understood to mean A only, B only, or both A and B.

[0236] fuel cell In one aspect, the disclosure provides one or more fuel cells for processing a feedstock material. FIG. 1 illustrates a schematic of a fuel cell according to some embodiments. The fuel cell can include an electrochemical circuit including an anode (101), a cathode (103), and an electrolyte (102) between the anode and the cathode. The electrochemical circuit can include an electrical load (104) configured to receive electrical energy generated by the fuel cell. The fuel cell can include a first channel (105, "anode channel") with a first inlet (106) and a first outlet (107), the first channel in fluid communication with the anode. The anode channel can include an anode gas diffusion layer (GDL), which can be referred to as an anode diffusion layer. The fuel cell can include a second channel (108, cathode channel) with a second inlet (109) and a second outlet (110), the second channel in fluid communication with the cathode. The cathode channel can include a cathode GDL, which can be referred to as a cathode diffusion layer.

[0237] The feed material (111) can include hydrogen. The feed material can be fed to the first inlet (106) such that the feed material contacts the anode. The feed material can diffuse to the anode catalyst where it dissociates into protons and electrons. The fuel cell uses the anode to convert H2→2H + +2e - The first half of the reaction can be carried out by adding protons (H + ) can be conducted through the electrolyte to the cathode, while electrons (e - ) is directed to travel along an external circuit through an electrical load to the cathode. A stream containing an oxidant (113, e.g., oxygen) can be provided to the second inlet (109) such that the stream contacts the cathode. The fuel cell uses the cathode to convert 2H + +2e -The latter reaction can occur involving +1 / 2O2 → H2O. The oxygen can react with the protons and electrons (both of which have traveled from the anode through the electrolyte and external circuit, respectively) to form a by-product (e.g., water). Overall, the fuel cell can perform the electrochemical reaction involving 2H2 + O2 → 2H2O. The standard potential of the electrochemical reaction is approximately 1.23 volts. The output voltage of a fuel cell can be lower than the standard potential due to potential losses (e.g., due to reaction rate losses, resistive losses, and / or mass transfer losses) during operation of the fuel cell.

[0238] The feedstock material (111) can be processed by one or more fuel cells to generate energy (e.g., electrical energy). In some embodiments, the feedstock material can be provided or received from one or more components or subcomponents of an ammonia reforming system (112, e.g., a system for cracking or decomposing ammonia into hydrogen and nitrogen). The feedstock material from the ammonia reforming system can include, for example, a storage section (114) for storing fuel (e.g., hydrogen, nitrogen, and / or ammonia) and, optionally, a reactor (115) for reacting the fuel to produce hydrogen and nitrogen (e.g., in a volume ratio of H2 to N2 of about 3:1).

[0239] In some cases, processing a feed material containing hydrogen and nitrogen can reduce fuel cell power compared to processing high purity hydrogen (e.g., greater than 99% purity). FIG. 2A shows a current-voltage characteristic plot of a fuel cell when the fuel cell is processing a feed material containing high purity hydrogen (e.g., about 99.999% purity hydrogen by volume) versus a feed material containing a mixture of about 75% hydrogen and about 25% nitrogen. The fuel cell receiving the mixture of hydrogen and nitrogen showed significantly lower electrical energy production. FIG. 2B illustrates the diffusion and transport of H2 versus H2 / N2 in the GDL of an exemplary fuel cell. When the GDL is used for diffusion and transport of a feed material containing mainly hydrogen, hydrogen can flow from the inlet of the GDL to the outlet of the GDL. As hydrogen flows through the GDL, it can also diffuse into the proton exchange membrane (PEM) where dissociation or transfer of ions occurs. Without being bound to a particular theory, when a GDL is used to transport a feed material containing both hydrogen and nitrogen (e.g., a hydrogen / nitrogen mixture), the transport of hydrogen to the PEM may be limited, in part, due to nitrogen deposition or accumulation within the GDL (nitrogen may weaken the flow). This accumulation may lead to greater potential losses associated with mass transfer of hydrogen within the GDL. In some cases, this accumulation may result in uneven distribution of hydrogen through the GDL (e.g., one portion of the GDL may accept less hydrogen compared to other portions of the GDL). In some cases, this accumulation may result in uneven distribution of hydrogen to the anode (e.g., one portion of the anode may accept less hydrogen compared to other portions of the anode). In some cases, this accumulation may result in poor hydrogen ion transport through the PEM. This accumulation may lead to reduced fuel cell performance and / or fuel cell starvation.

[0240] In some embodiments, the anode channel can include one or more features configured to improve processing of feed materials including hydrogen and nitrogen by the fuel cell. In some embodiments, the one or more features can include one or more cuts, one or more cutouts, and / or one or more grooves. The one or more features can be configured to continuously purge nitrogen from the fuel cell. Reducing nitrogen accumulation in at least a portion of the anode can increase the hydrogen consumption rate of the fuel cell, increase the output voltage of the fuel cell, or both. In some cases, reducing nitrogen accumulation in at least a portion adjacent to the anode can increase the hydrogen consumption rate of the fuel cell, increase the output voltage of the fuel cell, or both. The one or more features can be configured to purge nitrogen from the fuel cell while the fuel cell is generating electricity. The anode channel including one or more features can include a GGL including one or more features.

[0241] 3 illustrates the performance improvement of an anode channel with one or more cuts. When a mixture of hydrogen and nitrogen (e.g., about 3:1 volume ratio) is fed to the fuel cell for processing to generate electrical energy, the output voltage of the fuel cell with one or more cut structures in the anode channel can be significantly higher than the output voltage of a fuel cell without any cuts in the anode channel. In some cases, a fuel cell with a higher cut density on the surface of the anode channel can exhibit better performance (e.g., higher output voltage when processing a hydrogen / nitrogen mixture to generate electrical energy) compared to a fuel cell with a lower cut density on the surface of the anode channel.

[0242] FIG. 4 illustrates the performance improvement of an anode channel with one or more cutouts. When a mixture of hydrogen and nitrogen (about 3:1 volume ratio) is fed to the fuel cell for processing to generate electrical energy, the output voltage of a fuel cell with one or more cutout structures in the anode channel can be significantly higher than the output voltage of a fuel cell without any cutouts in the anode channel. In some cases, a fuel cell with a higher cutout density on the surface of the anode channel can exhibit better performance (e.g., higher output voltage when processing a hydrogen / nitrogen mixture to generate electrical energy) compared to a fuel cell with a lower cutout density on the surface of the anode channel. In some cases, a fuel cell with a too high cutout density on the surface of the anode channel can exhibit reduced performance compared to a fuel cell with a lower cutout density on the surface of the anode channel.

[0243] 5 illustrates a schematic of the improved performance of the anode channel with various multi-layer anode channel structures. The multi-layer anode channel structure can include multiple layers with one or more cuts, cutouts, grooves, or any combination thereof. When a mixture of hydrogen and nitrogen is fed to a fuel cell for processing to generate electrical energy, the output voltage of the fuel cell with the multi-layer anode channel structure can be significantly higher than the output voltage of a fuel cell without the multi-layer anode channel structure.

[0244] As shown in Figures 3, 4, and 5, one or more configurations of the anode channel can enable the generation of at least 50% of a reference power, the reference power being generated using a fuel cell receiving a stream containing at least 99 mole percent hydrogen at a first inlet. For example, the "Cut 2" structure shown in Figure 3 exhibits about 60% of the voltage of the reference power at a current of about 20 amps. Some structures exhibit a voltage of the reference power, such as nearly 100% of the "Structure 1" shown in Figure 5. The fuel cell power and the reference power can be generated at the same current or the same hydrogen consumption rate. In some cases, the power is at least 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power. In some cases, the power is at most 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0245] The one or more features can increase the hydrogen consumption rate of the fuel cell. The increase in hydrogen consumption rate of the fuel cell can be compared to a comparable fuel cell without any features. In some cases, the one or more features increase the hydrogen consumption rate by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%. In some cases, the one or more features increase the hydrogen consumption rate by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%. In some cases, the hydrogen consumption rate can be at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen supplied to the fuel cell. In some cases, the hydrogen consumption rate can be up to about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen supplied to the fuel cell.

[0246] In some cases, the hydrogen consumption rate of the fuel cell can be adjusted to maintain the autothermal reforming process of the ammonia reformer. An autothermal reforming process can be interpreted as a process in which the ammonia reforming process of the ammonia reformer produces a net positive hydrogen by burning or consuming at least a portion of the hydrogen produced by the ammonia reformer. In some cases, the autothermal reforming process of the ammonia reformer is maintained by burning at least a portion of the hydrogen (e.g., unconverted hydrogen) that is supplied to the fuel cell but not consumed by the fuel cell. For example, the unconverted hydrogen may be directed to one or more fired heaters of the ammonia reformer and burned in one or more fired heaters to heat the ammonia reformer. In some cases, the autothermal reforming process of the ammonia reformer is maintained by burning at least a portion of the hydrogen that is supplied to the fuel cell but not consumed by the fuel cell, and further by electrical heating obtained by at least a portion of the power generated from the fuel cell. In some cases, the autothermal reforming process of the ammonia reformer is maintained by burning at least a portion of the hydrogen that is produced by the ammonia reformer, and further by electrical heating obtained by at least a portion of the power generated from the fuel cell.

[0247] The hydrogen consumption rate may be adjusted by adjusting the load power of the fuel cell (e.g., the power required by a device in electrical communication with the fuel cell). In some cases, the hydrogen consumption rate of the fuel cell is about 20%-40% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 30%-50% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 40%-60% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 50%-70% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 60%-80% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 70%-90% of the hydrogen supplied to the fuel cell to maintain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is about 55%-75% of the hydrogen supplied to the fuel cell to sustain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is at least about 20, 30, 40, 50, 60, 70, 80, or 90% to sustain the autothermal reforming process of the ammonia reformer. In some cases, the hydrogen consumption rate is at most about 20, 30, 40, 50, 60, 70, 80, or 90% to sustain the autothermal reforming process of the ammonia reformer.

[0248] In some cases, the hydrogen consumption rate is maintained within a selected tolerance range of the target hydrogen consumption rate to maintain the autothermal reforming process of the ammonia reformer. For example, for a target hydrogen consumption rate of 50% with a selected tolerance range of 10%, the hydrogen consumption rate can be maintained in a range of 45% to 55%. In some cases, the selected tolerance range of the target hydrogen consumption rate is at least about 1%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% of the target consumption rate. In some cases, the selected tolerance range of the target hydrogen consumption rate is at most about 1%, 5%, 10%, 15%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% of the target consumption rate. In some cases, the hydrogen consumption rate is adjusted at least in part based on the temperature of the ammonia reformer. In some cases, as the temperature of the ammonia reformer or one or more fired heaters, the hydrogen consumption rate decreases and more hydrogen is delivered to the fired heater(s). In some cases, as the temperature of the ammonia reformer or one or more fired heaters, the ammonia reformer or one or more fired heaters, the hydrogen consumption rate increases and less hydrogen is delivered to the fired heater(s).

[0249] In some cases, the hydrogen consumption rate of the fuel cell is maintained within a selected tolerance of the target hydrogen consumption rate, and the one or more air flow rates including at least oxygen provided by the one or more air supply units are adjusted to maintain the autothermal reforming process of the ammonia reformer. In some cases, the one or more air flow rates are decreased (leading to less oxygen being provided to the one or more fired heaters) when the temperature of the one or more fired heaters of the ammonia reformer or the temperature of the ammonia reformer begins to increase. In some cases, the one or more air flow rates are increased (leading to more oxygen being provided to the one or more fired heaters) when the temperature of the one or more fired heaters of the ammonia reformer or the temperature of the ammonia reformer begins to decrease. In some cases, both the hydrogen consumption rate of the fuel cell and the one or more air flow rates are simultaneously adjusted based at least in part on the temperature of the one or more fired heaters of the ammonia reformer and / or the temperature of the ammonia reformer.

[0250] The one or more features may increase the output voltage of the fuel cell. The increase in the output voltage of the fuel cell can be compared to a comparable fuel cell without any of the features. In some cases, the one or more features increase the output voltage by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%. In some cases, the one or more features increase the output voltage by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0251] The one or more features can increase the power density of the fuel cell. The increase in the power density of the fuel cell can be compared to a comparable fuel cell without any features. In some cases, the one or more features can increase the power density by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%. In some cases, the one or more features can increase the power density by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%. The power density of the fuel cell can be at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L (i.e., the ratio of power output to the volume of the fuel cell(s) or fuel cell(s) stack(s). The power density of the fuel cell can be up to about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0252] The one or more features can reduce the physical footprint (e.g., size / volume, weight, etc.) of the fuel cell. The reduced footprint allows fuel cells to be integrated into applications where reduced weight and / or volume is desirable (e.g., aircraft) or where size is limited and power requirements are high (e.g., some industrial vehicles). In some embodiments, fuel cells comprising one or more features have a ratio of fuel cell power output to anode projected surface area of ​​at least about 0.05 W / cm. 2 In some embodiments, the ratio can be configured to obtain at least about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm. 2 In some embodiments, the ratio can be up to about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm 2The ratio may be based on an anode channel receiving a first continuous flow including about 25 mole percent nitrogen and about 75 mole percent hydrogen, and a cathode channel receiving a second continuous flow including at least 20 mole percent oxygen (e.g., air). In some cases, the ratio may be based on a first continuous flow including a hydrogen flow rate of at least about 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, or 100000 moles / second. In some cases, the ratio may be based on a second continuous flow including an oxygen flow rate of at least about 0.0001, 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000, 1000000 moles / second. In some cases, the ratio may be based on a first continuous flow including hydrogen and nitrogen from an ammonia reformer. The projected surface area may be interpreted as the maximum possible surface area of ​​the anode projected onto a flat plane. The projected surface area may be the surface area of ​​the largest surface of the anode, which may be defined by the largest plane of the anode.

[0253] FIG. 6 illustrates a schematic of a fuel cell stack or module (601) comprising a plurality of fuel cells, according to some embodiments. Each fuel cell of the plurality of fuel cells may comprise one or more components. The one or more components may comprise one or more cathode channels (e.g., for air flow), a cathode current collecting layer, and a cathode gas diffusion layer (603, GDL). In some embodiments, the one or more components may further comprise an anode gas diffusion layer (605; GDL) and an anode current collecting layer (606). In some cases, the one or more components may further comprise an electrolyte (604) disposed between the cathode GDL (603) and the anode GDL (605). The plurality of fuel cells may be coupled adjacent to one another.

[0254] The fuel cell structure may be suitable for use in one or more fuel cell stacks or modules comprising one or more fuel cells. A fuel cell module may comprise a stack of fuel cells or multiple stacks of fuel cells. The fuel cells may be arranged in a horizontal or circular configuration. The fuel cells of a fuel cell stack may be arranged on top of and / or next to each other. Each of the fuel cells may comprise one or more inlets for receiving a feedstock material. The fuel cell stack or one or more fuel cells of the fuel cell stack may be in fluid communication with an ammonia reformer or reactor to receive the feedstock material for generating electricity. The fuel cells may be coupled in series or in parallel. In some cases, one or more fuel cell stacks or modules may be in fluid communication with each other in series or in parallel. The fuel cells may be configured to process the feedstock material to generate electrical energy. A fuel cell stack or module (e.g., 601) may comprise any number of fuel cells. For example, the fuel cell may comprise at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000, 4000, 5000, 6000, 7000, 8000, 9000, 10,000 fuel cells. The fuel cell may comprise at most 2, 3, 4, 5, 6, 7, 8, 9, 10, 100, 200, 300, 400, 500, 600, 7000, 8000, 9000, 10,000 fuel cells.

[0255] FIG. 7 illustrates a schematic of durability test results of a fuel cell stack with a multi-layer gas diffusion layer structure fed with a mixture of hydrogen and nitrogen, according to some embodiments. The durability test was conducted using a fuel cell stack with 32 fuel cells and a gas diffusion layer with a double-layer structure. A gas mixture of hydrogen and nitrogen (including a hydrogen to nitrogen volume ratio of 3:1) was fed to the fuel cell stack for one hour of durability testing. The gaseous hydrogen was fed at a volumetric flow rate of 15 standard liters / minute, and the gaseous nitrogen was fed at a volumetric flow rate of 5 standard liters / minute. As shown in the plot of FIG. 7, the power output of the fuel cell stack stabilized at about 572 watts.

[0256] FIG. 8 illustrates a schematic of durability test results of a fuel cell stack with a multi-layer gas diffusion layer structure fed with a mixture of hydrogen and nitrogen (volume ratio of hydrogen to nitrogen 3:1) produced from an ammonia reforming process according to some embodiments. The ammonia concentration in the hydrogen mixture can be maintained below 1 ppm. Five fuel cell stacks were tested using the gas mixture produced during the ammonia reforming process. No obvious difference in fuel cell performance was observed between the first test scenario involving the treatment of reformate gas produced during ammonia reforming and the second test scenario involving the treatment of a mixture of hydrogen and nitrogen from a gas tank. Moreover, no significant degradation in fuel cell performance was observed during the operation period.

[0257] The fuel cells in the stack can be electrically coupled. The fuel cells can be electrically coupled in series to provide higher current. In some cases, the fuel cells can provide an output voltage of at least about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, or 1.2V. In some cases, the fuel cells can provide an output voltage of up to about 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, or 1.2V. The fuel cells electrically coupled in series can provide a total output voltage approximately equal to the sum of the output voltages of each of the fuel cells coupled in series. For example, the plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 V. The plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 kV. The plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 MV. The plurality of fuel cells can provide at most about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900V. The fuel cells can provide up to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 kV. The fuel cells can provide up to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 MV.

[0258] Fuel cells can be electrically coupled in parallel to provide higher currents. The fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 A. The fuel cells can provide up to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 A. Fuel cells electrically coupled in parallel can provide a total output current equal to the sum of the output currents of each of the fuel cells coupled in parallel. For example, the plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 A. The plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 kA. The plurality of fuel cells can provide at least about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 MA. The plurality of fuel cells can provide at most about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 A. The plurality of fuel cells can provide up to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 kA. The plurality of fuel cells can provide up to about 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700, 800, or 900 MA.

[0259] The one or more ammonia reformers can be configured to supply multiple streams comprising hydrogen and nitrogen to the multiple fuel cells. In some embodiments, the one or more ammonia reformers comprise one ammonia reformer. In some embodiments, the one or more ammonia reformers comprise at least 2, 3, 4, 5, 6, 7, 8, 9, or 10 ammonia reformers.

[0260] In some embodiments, at least one fuel cell of the plurality of fuel cells outputs a different power than other fuel cells of the plurality of fuel cells. In some cases, at least one fuel cell of the plurality of fuel cells is configured to reduce its power output, while other fuel cells of the plurality of fuel cells maintain their respective power outputs. For example, one or more fuel cells of the plurality of fuel cells may operably or intermittently reduce their power output to between about 0% and 50% of a first power level, while other fuel cells of the plurality of fuel cells output between about 50% and 100% of the first power level. In some cases, at least one fuel cell of the plurality of fuel cells is configured to increase its power output, while other fuel cells of the plurality of fuel cells maintain their power output.

[0261] In some cases, a system including a plurality of fuel cells can be configured to detect a failure of at least one fuel cell of the plurality of fuel cells. The failure can be detected by, for example, a temperature sensor, a voltage sensor, a current sensor, a pressure sensor, a flow sensor, etc. operably coupled to the at least one fuel cell and the controller. In some cases, after detecting the failure, at least one fuel cell of the plurality of fuel cells can be configured to stop or reduce power generation based on the failure and / or the inlet flow of the at least one fuel cell can be reduced or stopped based on the failure, while other fuel cells of the plurality of fuel cells can continue to output power. The controller can operate the at least one fuel cell to reduce or stop the inlet flow. In some cases, the failure can include a temperature of the inlet flow above a threshold temperature, an ammonia concentration above a threshold concentration, a pressure of the inlet flow above a threshold pressure, a voltage dropping below a threshold voltage, an inlet flow rate less than or greater than a threshold flow rate, etc. In some cases, after the failure is at least partially resolved, the controller can operate the at least one fuel cell to increase the inlet flow rate or power generation. In some cases, the fault is at least partially resolved when at least one of the following occurs: the temperature of the inlet stream returns to the target temperature range, the ammonia concentration returns to below the threshold concentration, the pressure of the inlet stream returns to the target pressure range, the voltage level returns to the target voltage range, or the inlet flow rate returns to the target flow rate range.

[0262] In some embodiments, the plurality of fuel cells comprises at least one fuel cell that differs in size, power output, hydrogen consumption rate, power density, or operating temperature from other fuel cells of the plurality of fuel cells, hi some embodiments, the plurality of fuel cell stacks or modules comprises at least one fuel cell stack or module that differs in size, power output, hydrogen consumption rate, power density, or operating temperature from other stacks or modules of the plurality of fuel cell stacks or modules.

[0263] In some embodiments, at least one fuel cell of the plurality of fuel cells is in series fluid communication with at least one other fuel cell of the plurality of fuel cells. For example, an outlet stream of one or more fuel cells of the plurality of fuel cells can provide an inlet stream of one or more other fuel cells of the plurality of fuel cells. In some cases, at least one fuel cell of the plurality of fuel cells has a different size, power output, hydrogen consumption rate, power density, or operating temperature than at least one other fuel cell of the plurality of fuel cells with which it is in series fluid communication.

[0264] In some embodiments, at least one fuel cell of the plurality of fuel cells is in parallel fluid communication with at least one other fuel cell of the plurality of fuel cells, and in some cases, at least one fuel cell of the plurality of fuel cells has a different size, power output, hydrogen consumption rate, power density, or operating temperature than at least one other fuel cell of the plurality of fuel cells with which it is in parallel fluid communication.

[0265] In some embodiments, at least one fuel cell stack or module of the plurality of fuel cell stacks or modules is in series fluid communication with at least one other fuel cell stack or module of the plurality of fuel cell stacks or modules. For example, an outlet stream of one or more fuel cell stacks or modules of the plurality of fuel cell stacks or modules can provide an inlet stream of one or more other fuel cell stacks or modules of the plurality of fuel cell stacks or modules. In some cases, at least one fuel cell stack or module of the plurality of fuel cell stacks or modules differs in size, power output, hydrogen consumption rate, power density, or operating temperature from at least one other fuel cell stack or module of the plurality of fuel cell stacks or modules with which it is in series fluid communication. For example, a first fuel cell stack that discharges an outlet stream to an inlet stream of a second fuel cell stack may be larger in size or may output higher power.

[0266] In some embodiments, at least one fuel cell stack or module of the plurality of fuel cell stacks or modules is in parallel fluid communication with at least one other fuel cell stack or module of the plurality of fuel cell stacks or modules. In some cases, a stream including a feedstock may be distributed between two or more fuel cell stacks or modules of the plurality of fuel cell stacks or modules within at least about 1%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% of a target flow rate (e.g., a target inlet flow rate of a single fuel cell stack). In some cases, a stream including a feedstock may be distributed between two or more fuel cell stacks or modules of the plurality of fuel cell stacks or modules within at most about 1%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, or 100% of a target flow rate. In some cases, a stream including a feedstock may be distributed between two or more fuel cell stacks or modules of the plurality of fuel cell stacks or modules by a distribution coefficient. For example, if the distribution coefficient is about 4-5, the first fuel cell stack may receive a stream containing about 4-5 times more feed material (e.g., by weight, volume, moles, or concentration of feed material) than the second fuel cell stack. In some cases, the distribution coefficient may be at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In some cases, the distribution coefficient may be up to about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In some cases, at least one fuel cell stack or module differs in size, power output, hydrogen consumption rate, power density, or operating temperature from at least one other fuel cell stack or module of the plurality of fuel cell stacks or modules in parallel fluid communication.

[0267] In some cases, the fuel cell may be operated to intermittently decrease the hydrogen consumption rate (thus increasing the flow rate of unconverted hydrogen exiting the fuel cell) and purge at least one of hydrogen, nitrogen, or water. The hydrogen consumption rate can be reduced by directing at least a portion of the first continuous stream of hydrogen and nitrogen to an ammonia reformer. In some cases, the first continuous stream can be in direct fluid communication with one or more fired heaters of the ammonia reformer. In some cases, at least a portion of the first continuous stream can be combusted in one or more combustion exhausts of the one or more fired heaters. In some cases, at least a portion of the first continuous stream including hydrogen is exhausted from one or more combustion exhausts of the one or more fired heaters.

[0268] The one or more fired heaters can be in communication with the ammonia reformer to heat the ammonia reformer. The one or more fired heaters can be in fluid communication with the fuel cell to receive at least a portion of the first continuous flow.

[0269] The one or more features can be configured to facilitate purging of the selected material from the anode gas diffusion layer. The selected material can include one or more of nitrogen, ammonia, water, or one or more impurities. In some cases, the fuel cell can include one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell. In some cases, the unconverted hydrogen from the multiple fuel cells can be directed to at least one ammonia reformer or reactor for combustion heating. The one or more air supply units can provide at least oxygen to the ammonia reformer for combustion of the unconverted hydrogen. In some cases, the unconverted oxygen from the multiple fuel cells (e.g., one or more cathode outlet streams) can provide at least oxygen to the ammonia reformer for combustion of the unconverted hydrogen. In some cases, water can be removed from the stream comprising the unconverted hydrogen prior to combusting the unconverted hydrogen. In some cases, the stream comprising the unconverted hydrogen can be combusted. The systems and methods disclosed herein can be implemented using one or more fuel cells. The one or more fuel cells can be arranged in a fuel cell stack as disclosed elsewhere herein. In some non-limiting embodiments, the one or more fuel cells may include an anode, a cathode, and an electrolyte disposed between the anode and the cathode. In some cases, the anode may include a gas diffusion layer including one or more channels for conducting the feed material through the gas diffusion layer of the anode to facilitate processing of the feed material to generate an electric current. In some cases, the one or more channels may include one or more surface features configured to enhance diffusion of the feed material through the gas diffusion layer of the anode. The feed material may include, for example, a gas mixture of hydrogen and nitrogen. In some cases, processing the feed material may include dissociating one or more hydrogen molecules of the feed material into one or more protons and one or more electrons.

[0270] In some embodiments, the one or more fuel cells may be in fluid communication with the one or more reactor modules for catalytically decomposing ammonia. The one or more fuel cells may be configured to receive hydrogen and / or nitrogen produced using the one or more reactor modules and process the hydrogen / nitrogen mixture to produce electrical energy.

[0271] In some cases, the one or more fuel cells may be in fluid communication with the one or more reactors. The one or more reactors may be configured to catalytically decompose ammonia to produce hydrogen. An outlet stream from the one or more reactors may include hydrogen, nitrogen, and / or unconverted ammonia. The outlet stream from the one or more reactors may be directed to one or more fuel cells, which may be configured to use (i.e., process) the outlet stream, or a portion thereof, to generate electrical energy.

[0272] In one aspect, the disclosure provides a method for processing hydrogen. The method may include feeding a reactor outlet stream comprising hydrogen and / or nitrogen to one or more fuel cells. The reactor outlet stream may be from a reactor for catalytic decomposition of ammonia or a reformer. In some cases, the reactor outlet stream may be from various components or subcomponents of a reformer for catalytic decomposition of ammonia. The various components or subcomponents may comprise, for example, a reactor, an adsorption tower, or a heat exchanger of a reformer. The method may further include processing the reactor outlet stream to generate electricity (i.e., electrical current) using one or more fuel cells.

[0273] In some cases, the outlet stream from the one or more reactors may be directed to one or more adsorbents to remove excess or trace ammonia before the reactor outlet stream is directed to the one or more fuel cells. Because ammonia can be harmful to fuel cells, the adsorbents can help maintain the performance and / or life of the one or more fuel cells. The adsorbents can be replaceable (e.g., as cartridges) after a certain number of cycles or operations. In some embodiments, the concentration of ammonia in the outlet stream from the one or more adsorbents can be further reduced (before providing the outlet stream from the one or more adsorbents to the one or more fuel cells) using an additional ammonia filtration system in series fluid communication with the one or more adsorbents. The additional ammonia filtration system may be an adsorbent-based, membrane-based, absorbent-based, solvent-based, water-based, or acid-based ammonia filtration system. In some cases, the additional ammonia filtration system comprises one or more ammonia filtration cartridges, such that when the one or more cartridges are fully or at least partially used, the one or more fully or at least partially used cartridges can be replaced with one or more new ammonia filtration cartridges.

[0274] In some cases, the fuel cell may be in fluid communication with multiple adsorption towers. The multiple adsorption towers may include at least a first adsorption tower and a second adsorption tower. The first and / or second adsorption towers may be used to remove any traces of ammonia from the reactor outlet stream before the reactor outlet stream is directed to the one or more fuel cells. While the first adsorption tower is in use, the second adsorption tower may be regenerated (e.g., so that ammonia is desorbed from the second adsorption tower). When the first adsorption tower becomes fully saturated (e.g., the first adsorption tower cannot adsorb additional ammonia), the second adsorption tower may be partially or fully regenerated and ready for use in another cycle or operation. In any of the embodiments described herein, two, three, four, five, six, seven, eight, nine, ten, or more adsorption towers may be used to filter the reactor outlet stream before it reaches the one or more fuel cells.

[0275] Proton exchange membrane fuel cell The fuel cells disclosed herein may include various types of fuel cells. In some cases, the electrolyte may include a membrane. In some cases, the membrane may include a proton exchange membrane. In some cases, the fuel cell may include one or more proton exchange membrane fuel cells (PEMFCs) that include a proton conducting polymer electrolyte membrane. Proton exchange membrane fuel cells can be used to convert chemical energy to electrical energy by electrochemically reacting hydrogen and oxygen. In some cases, the PEMFC may include a proton conducting polymer membrane that separates an anode side and a cathode side of the PEMFC. In some cases, the fuel cell may include one or more PEMFCs, one or more solid oxide fuel cells (SOFCs), one or more molten carbonate fuel cells (MCFCs), one or more alkaline fuel cells (AFCs), one or more alkaline membrane fuel cells (AMFCs), or one or more phosphoric acid fuel cells (PAFCs).

[0276] The fuel cells of the present disclosure may include one or more PEMFCs suitable for use with mixtures of hydrogen and / or nitrogen. In some cases, the fuel cells of the present disclosure may be used to generate electrical energy from hydrogen gas mixtures containing impurities that would otherwise degrade the performance of conventional fuel cells (some of which may require up to about 99.7% pure hydrogen as a feedstock). The fuel cells of the present disclosure may provide better performance compared to fuel cells with dead-end configurations (e.g., fuel cells without an outlet in the anode channel configured to direct unconverted hydrogen and / or nitrogen out of the fuel cell). Dead-end configurations may not allow for efficient processing of H2 / N2 mixtures, since N2 concentrations may build up without proper purging. The fuel cells of the present disclosure may provide better performance compared to fuel cells with intermittent purging operations, which may not allow for efficient processing of H2 / N2 mixtures (since N2 concentrations may build up without continuous purging). In some cases, continuous purging may be defined based on a purge time ratio (the ratio of the total purge time during which power is generated by the one or more fuel cells to the total operating time). In some cases, the one or more fuel cells are continuously purged when the purge time ratio is at least about 0.5 (i.e., N2 purging occurs for at least about 50% of the total operating time). In some cases, the one or more fuel cells are continuously purged when the purge time ratio is at least about 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. In some cases, the purge time ratio is about 1 (i.e., N2 purging occurs for about 100% of the total operating time). The fuel cells disclosed herein can also provide improved performance compared to flow-through fuel cells that allow H2 / N2 mixtures (e.g., fuel cells with an outlet in the anode channel configured to direct unconverted hydrogen and / or nitrogen out of the fuel cell). This is because such flow-through fuel cells can become fuel starved if an excess of H2 / N2 mixture is not provided or if the H2 from the H2 / N2 mixture is not sufficiently dispersed to the anode.Fuel cells of the present disclosure can be configured to utilize and process H2 / N2 mixtures without suffering from similar degradation in performance that may result from the buildup of N2 concentrations. These advantages can be realized, for example, by using an anode channel optimally configured for the fuel cell (e.g., an anode channel with cuts, cutouts, or grooves).

[0277] raw material In one aspect, the present disclosure provides a fuel cell structure that can be compatible with a variety of gas mixtures containing hydrogen, nitrogen, ammonia, and / or other reformate gases. Such gas mixtures can be obtained by an ammonia reformer or a reactor configured to process (i.e., catalytically decompose) ammonia. Although hydrogen has a relatively high gravimetric density (measured in MJ / kg), fuel storage systems for compressed and liquefied hydrogen are often complicated because specialized storage conditions must be established and maintained. For example, storage of hydrogen as a gas would require high-pressure tanks (e.g., 350-700 bar or 5,000-10,000 psi). Storing hydrogen as a liquid may require cryogenic temperatures, since the boiling point of hydrogen at 1 atmosphere is -252.8°C. Using ammonia as a hydrogen carrier can provide several advantages over storage and transportation of pure hydrogen, including easy storage and convenient transportation at relatively standard conditions (0.8 MPa and 20°C in the liquid state). Ammonia also has a relatively high hydrogen content (17.7% by weight or 120 grams of H2 per liter of liquid ammonia). Furthermore, the production of ammonia using the Haber-Bosch process can be powered by renewable energy sources (e.g., photovoltaic, solar thermal, wind turbine, geothermal, and / or hydroelectric), making the production process environmentally safe and friendly since N2 is the only by-product and there are no further emissions of CO2. Once ammonia is made, it can be processed to release hydrogen by a dehydrogenation process (i.e., by dissociating, decomposing, reforming, or cracking the ammonia).

[0278] The feedstock may contain various concentrations of hydrogen, nitrogen, and ammonia. If the feedstock is supplied directly from an ammonia reformer, the ratio of nitrogen to hydrogen may be about 1 part nitrogen to 3 parts hydrogen by molar ratio. Depending on the degree of conversion of ammonia by the reformer, some ammonia may be present in the feedstock. In some cases, the feedstock may be mixed with another gas before being supplied to the fuel cell or fuel cells. For example, the feedstock may be mixed with a high purity hydrogen gas stream (e.g., greater than 99% purity). The feedstock may be mixed with a high purity nitrogen gas stream (e.g., greater than 99% purity). The feedstock may be purified before being supplied to the fuel cell or fuel cells. For example, the feedstock may be contacted with an adsorber or absorber to reduce the ammonia concentration in the feedstock. In some cases, the feedstock may be obtained by mixing high purity nitrogen and high purity hydrogen streams. Thus, the concentrations and amounts of hydrogen, nitrogen, and ammonia supplied to the fuel cell or fuel cells may be varied.

[0279] FIG. 15 illustrates ammonia as an energy carrier and various density characteristics of ammonia compared to other types of fuels. The H2 storage capacity of NH3 is about 17.7% by weight and 120 grams of H2 per liter of ammonia. Compared to other fuel types, e.g., hydrogen, ammonia exhibits favorable volumetric density given its gravimetric density. Furthermore, compared to other types of fuels (including carbon-based fuels, e.g., methane, propane, methanol, ethanol, gasoline, E-10 gasoline, JP-8 jet fuel, or diesel), the use of ammonia as a fuel produces no harmful exhaust emissions, e.g., CO2, CO, or black carbon (soot), and (especially when combined with a selective catalytic reduction [SCR] catalyst) produces no NO2, CO, or black carbon (soot). xThus, by using ammonia as an energy carrier, some embodiments of the presently disclosed systems and methods can take advantage of (a) the high volumetric density of ammonia compared to hydrogen, and (b) the ability to transport ammonia at standard temperatures and pressures without the need for the complex, high pressure storage vessels typically used to store and transport hydrogen, while still taking advantage of the advantages of hydrogen fuel (e.g., environmentally safe and high gravimetric energy density) once ammonia is cracked into hydrogen.

[0280] In some embodiments, the feedstock comprises a volume fraction of about 30% to about 99.7% H2. In some embodiments, the feedstock comprises a volume fraction of about 30% to about 99.99% H2. In some embodiments, the feedstock comprises a volume fraction of about 70% to about 99.999% H2. In some embodiments, the feedstock comprises a volume fraction of about 70% to about 80% H2, when provided by ammonia reforming. In some embodiments, one or more hydrogen separation systems (e.g., pressure swing adsorption (PSA) or membrane separation) can be used to increase the volume fraction of hydrogen in the feedstock.

[0281] In some embodiments, the feedstock material comprises H2 at a volume fraction of about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween. In some embodiments, the feedstock material comprises H2 at a volume fraction of at least about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween. In some embodiments, the feedstock material comprises H2 at a volume fraction of up to about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween. In some embodiments, the feedstock material comprises H2 at a volume fraction of about 30% to about 99.7%, about 35% to about 95%, about 40% to about 90%, about 45% to about 85%, about 50% to about 80%, about 55% to about 75%, about 60% to about 70%, about 65% to about 95%.

[0282] In some embodiments, the feedstock material comprises H2 in a mole fraction of at least about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween. In some embodiments, the feedstock material comprises H2 at a mole fraction of up to about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween.

[0283] In some embodiments, the feedstock material comprises H2 at a partial pressure fraction of at least about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween. In some embodiments, the feedstock material comprises H2 at a partial pressure fraction of up to about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99.7%, or any value therebetween.

[0284] The feedstock material can include various concentrations of nitrogen. In some cases, the feedstock material includes a volume fraction of at least 10% nitrogen. In some cases, the feedstock material includes a volume fraction of at least 20% nitrogen. In some cases, the feedstock material includes a volume fraction of about 20% to about 30% nitrogen. In some cases, the feedstock material includes a volume fraction of about 30% to about 50% nitrogen. In some cases, the feedstock material includes a volume fraction of about 40% to about 70% nitrogen. In some embodiments, the feedstock material includes a volume fraction of about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70% nitrogen, or any value therebetween. In some embodiments, the feedstock material comprises a nitrogen volume fraction of at least about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, or any value therebetween. In some embodiments, the feedstock material comprises a nitrogen volume fraction of up to about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, or any value therebetween. In some embodiments, the feedstock material comprises nitrogen in a volume fraction of about 10% to about 70%, about 15% to about 65%, about 20% to about 60%, about 25% to about 55%, about 30% to about 50%, about 35% to about 45%, about 40% to about 70%, or any value therebetween.

[0285] In some embodiments, the feedstock material comprises a partial pressure fraction of N2 of at least about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99%, or any value therebetween. In some embodiments, the feedstock material comprises a partial pressure fraction of N2 of up to about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99%, or any value therebetween.

[0286] In some embodiments, the feedstock material comprises N2 in a mole fraction of at least about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99%, or any value therebetween. In some embodiments, the feedstock material comprises N2 in a mole fraction of up to about 1%, about 5%, about 10%, about 15%, about 20%, about 25%, about 30%, about 35%, about 40%, about 45%, about 50%, about 55%, about 60%, about 65%, about 70%, about 75%, about 80%, about 85%, about 90%, about 95%, about 99%, or any value therebetween.

[0287] The feedstock may contain various concentrations of ammonia, in some embodiments, the feedstock contains ammonia at a concentration of less than about 0.1 ppm, about 0.2 ppm, about 0.3 ppm, about 0.4 ppm, about 0.5 ppm, about 0.6 ppm, about 0.7 ppm, about 0.8 ppm, about 0.9 ppm, about 1 ppm, about 1.2 ppm, about 1.4 ppm, about 1.6 ppm, about 1.8 ppm, about 2 ppm, or any value therebetween. In some embodiments, the feedstock comprises ammonia at a concentration of up to about 0.1 ppm, about 0.2 ppm, about 0.3 ppm, about 0.4 ppm, about 0.5 ppm, about 0.6 ppm, about 0.7 ppm, about 0.8 ppm, about 0.9 ppm, about 1 ppm, about 1.2 ppm, about 1.4 ppm, about 1.6 ppm, about 1.8 ppm, about 2 ppm, or any value therebetween. In some embodiments, the feedstock comprises ammonia at a concentration of about 0.1 ppm to about 2 ppm, about 0.2 ppm to about 1.8 ppm, about 0.3 ppm to about 1.6 ppm, about 0.4 ppm to about 1.4 ppm, about 0.5 ppm to about 1.2 ppm, about 0.6 ppm to about 1 ppm, about 0.7 ppm to about 0.9 ppm, or about 0.8 ppm to about 2 ppm. In some embodiments, the ammonia concentration in the first continuous stream is at most 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm. In some embodiments, the ammonia concentration in the first continuous stream is at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0288] The feedstock may be provided to the one or more fuel cells at a variety of pressures. The feedstock may be provided to the one or more fuel cells at a pressure of at least about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar absolute. The feedstock may be provided to the one or more fuel cells at a pressure of up to about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar absolute. The feedstock may be provided to the one or more fuel cells at a pressure of about 1-5 bar absolute. The pressure of the feedstock may be maintained within a selected tolerance range while the feedstock is provided to the one or more fuel cells. The selected tolerance range can be 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 150, 200, 300, 400, 500, or 1000 percent of absolute pressure. The pressure or flow rate of the feedstock can be adjusted while the feedstock is being fed to the one or more fuel cells. One or more flow regulators, pressure regulators, control units, or any combination thereof can be used to adjust the pressure or flow rate. For example, one or more pressure regulators can reduce the pressure of the feedstock being fed to the one or more fuel cells from about 5-10 bar absolute pressure to about 1.5-3 bar. The one or more flow regulators, pressure regulators, control units, or any combination thereof can be located upstream or downstream of the fuel cells. The one or more flow regulators, pressure regulators, control units, or any combination thereof can be located downstream of the fuel cells to prevent or reduce backflow of unconverted hydrogen or any other flow.

[0289] In some cases, the feedstock material can be provided to the multiple fuel cells, fuel cell stacks, or fuel cell modules as multiple streams. The flow rate or pressure of the multiple streams can be maintained or adjusted. The pressure or flow rate can be adjusted using one or more flow regulators, pressure regulators, control units, or any combination thereof. In some cases, at least one fuel cell of the multiple fuel cells can receive a stream at a flow rate different from the flow rate of other streams of the multiple streams. In some cases, each of the multiple fuel cells can receive one of the multiple streams at a flow rate about the same as the other flow rates of the other streams of the multiple streams or at a flow rate within a selected tolerance range of the other flow rates of the other streams. In some cases, the selected tolerance range is about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%. In some cases, the selected tolerance range is up to about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%.

[0290] Reformer FIG. 9 illustrates a block diagram of an exemplary system for processing a feedstock material 910 to generate electrical energy. The feedstock material 910 can include hydrogen. In some cases, the feedstock material 910 may further include one or more other gases, such as oxygen (O2), nitrogen (N2), and / or ammonia (NH3). The feedstock material 910 may include one or more reformate gases generated by an ammonia processing system. The system can be configured to crack or decompose a hydrogen carrier (e.g., ammonia, liquid organic hydrogen carrier (LOHC), formic acid (HCOOH), or methanol (CH3OH)) to extract or generate hydrogen. In some cases, the feedstock material 910 may include various impurities, such as unconverted ammonia that has passed through the ammonia processing system, nitrogen mixed with hydrogen extracted using the ammonia processing system, and / or other trace materials in the ammonia processing system.

[0291] The feedstock material 910 may be provided to a fuel cell 920. The fuel cell 920 may be designed or configured to process the hydrogen to generate electrical energy 930. The electrical energy 930 may be used to power various systems, vehicles, and / or devices, including, for example, land, air, water, marine, submarine, or amphibious vehicles, mobile or fixed electrical equipment, or stationary power grids. In some cases, the electrical energy 930 may be used as backup power for various systems, vehicles, and / or devices.

[0292] As described above, one or more fuel cells 920 can be used to generate electrical energy 930 (e.g., a current or a flow of electrons) using a feed material 910, which can include hydrogen and / or nitrogen. In some cases, the one or more fuel cells can generate electrical energy 930 by an electrochemical reaction of a fuel. The fuel can include hydrogen in the feed material 910. The electricity generated by the fuel cell can be used to power one or more systems, vehicles, or devices. In some embodiments, excess electricity generated by the fuel cell can be stored in one or more energy storage units (e.g., batteries) for future use. In some embodiments, the fuel cell can be provided as part of a larger fuel cell system.

[0293] In some non-limiting examples, the fuel cell system may include an electrolysis module. Electrolysis of a by-product (e.g., water) of one or more fuel cells may allow for the removal of the by-product by breaking it down into one or more components (e.g., oxygen and / or hydrogen). Electrolysis of the by-product may also produce another fuel (e.g., hydrogen) for the fuel cell. A portion of the energy required to operate the electrolysis module may be obtained from surplus power sources, including, but not limited to, solar power, wind power, hydroelectric power, nuclear power, combustion engines, combustion turbines, steam turbines, and the like. In some cases, the fuel cell may receive a feedstock material from one or more reformers. The one or more reformers may include a reformer configured to perform catalytic decomposition or cracking of ammonia to extract and / or produce hydrogen. An outlet stream from the reformer may include extracted hydrogen and / or other gases (e.g., nitrogen and / or ammonia). The outlet stream may correspond to a feedstock material usable by the fuel cell to generate electrical energy. In some cases, the reformer may be operated using thermal energy. In some cases, the reformer may be heated using a combustor that generates thermal energy to facilitate operation of the reformer. In some cases, the thermal energy may be generated from the combustion of chemical compounds (e.g., hydrogen or hydrocarbons). The hydrogen generated and / or extracted using the reformer may be fed to one or more fuel cells, which may create electrical energy to power one or more systems, subsystems, or devices that require electrical energy to operate. In some cases, the hydrogen generated and / or extracted using the reformer may be fed to one or more other reactors or reformers. In such cases, the one or more other reactors or reformers may be configured to combust the hydrogen to generate thermal energy. Such thermal energy may be used to heat one or more other reactors or reformers to facilitate another catalytic decomposition or cracking of ammonia to extract and / or create another hydrogen.In some cases, the reformer or reactor may be heated using electrical, resistive, or Joule heating. In some cases, the reformer or reactor may be heated using combustion and electrical, resistive, or Joule heating. In such cases, an electric current may be passed through an electric heater, catalyst, or catalyst bed of the reformer to directly heat the catalyst.

[0294] FIG. 10 illustrates a schematic process for supplying reformate gas to a fuel cell, according to some embodiments. The reformate gas may include a mixture of hydrogen and nitrogen. The mixture may comprise a ratio of hydrogen gas to nitrogen gas by weight or volume. The ratio may be, for example, X:Y, where X corresponds to hydrogen (e.g., 3 for ammonia reforming) and Y corresponds to nitrogen (e.g., 1 for ammonia reforming), and X and Y are any integers equal to or greater than 1. The reformate gas may include one or more gases that constitute an outlet stream from the reformer (or any component or subcomponent thereof). The reformer may comprise an ammonia reformer for catalytically decomposing ammonia. The catalytic decomposition of ammonia can be facilitated using a heat source. The heat source may comprise one or more combustors and / or one or more electric heaters. The one or more combustors may be configured to combust hydrogen, ammonia, one or more hydrocarbons, or any combination thereof to generate thermal energy. The one or more electric heaters may be configured to convert electrical energy to thermal energy by a Joule heating mechanism. Thermal energy can be used to facilitate the catalytic decomposition of ammonia.

[0295] Channel Features The one or more features can have a variety of sizes, shapes, and orientations. In some cases, the one or more features can comprise one or more cuts, one or more cutouts, one or more grooves, or any combination thereof. In some cases, the cuts can be incisions or slits in the anode channel. In some cases, the cuts can include a substantially small amount of material removal from the anode channel (e.g., zero or near zero material by weight, e.g., less than about 1-3% by weight). The cutouts can be openings in the anode channel. The cutouts can include a substantial amount of material removal from the anode channel. The grooves can be recesses or trenches in the anode channel with a depth that does not extend through the entire thickness of the anode channel. The grooves can include a substantial amount of material removal from the anode channel. The grooves can include a substantially small amount of material removal from the anode channel.

[0296] The one or more features may have a variety of depths. The one or more features may have a depth of less than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm. The one or more features may have a depth of more than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm. The depth of the one or more features may be interpreted relative to the thickness of the GDL. In some cases, the depth is at least 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the GDL. In some cases, the depth is at most 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the GDL.

[0297] The one or more features can have a variety of surface areas. The one or more features can extend across a portion of the surface of the anode channel. In some cases, the ratio of the projected surface area of ​​the one or more features to the projected surface area of ​​the anode channel is at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. In some cases, the ratio of the projected surface area of ​​the one or more features to the projected surface area of ​​the anode channel is at most 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0298] The one or more features can comprise any number of features. In some cases, the one or more features can comprise two or more features. The one or more features can comprise at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 features. The one or more features can comprise at most 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100 features.

[0299] The one or more features can include various orientations. In some cases, at least a first segment of a first feature in the two or more features is substantially parallel to a second segment of a second feature in the two or more features. In some cases, at least a first segment of a first feature in the two or more features is substantially perpendicular to a second segment of a second feature in the two or more features. In some cases, at least a first segment of a first feature in the two or more features is at an angle to a second segment of a second feature in the two or more features, the angle being between 0 and 90 degrees, between 0 and 30 degrees, between 15 and 75 degrees, or between 30 and 60 degrees. In some cases, the two or more features can be connected or disconnected. In some cases, the two or more features can intersect. The feature can be substantially parallel to the longest side of the anode channel. The feature can be substantially parallel to the shortest side of the anode channel. The one or more features can comprise various shapes. For example, the one or more features can comprise a substantially straight shape, a curved shape, a serpentine shape, or another shape.

[0300] FIG. 11 illustrates various examples of cut structures that can be utilized in the anode channel of a fuel cell. The cut structure may include a plurality of cuts across a surface of the anode channel of the fuel cell. The plurality of cuts may include one or more cuts in the surface of the anode channel to reduce nitrogen accumulation in the anode and promote nitrogen outflow from the fuel cell such that nitrogen does not accumulate in the anode gas diffusion layer. It is noted that, in this specification, the term "anode channel" may be interpreted as an "anode gas diffusion layer channel", an "anode current collection layer channel", or a combination of both.

[0301] The cuts may have a depth that extends into the anode channel ranging from about 0.01 millimeters to about 10 mm, in some embodiments, the depth is at least about 0.01 mm, about 0.05 mm, about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value therebetween. In some embodiments, the depth is at most about 0.01 mm, about 0.05 mm, about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value therebetween. In some embodiments, the depth is 0.01 mm to about 10 mm, about 0.05 mm to about 9 mm, about 0.1 mm to about 8 mm, 0.2 mm to about 7 mm, about 0.3 mm to about 6 mm, about 0.4 mm to about 5 mm, 0.5 mm to about 4 mm, about 0.6 mm to about 3 mm, about 0.7 mm to about 2 mm, 0.8 mm to about 1 mm, or about 0.9 mm to about 10 mm. In some embodiments, the one or more cuts may extend into the anode channel to a depth equal to the thickness of the anode channel.

[0302] In some embodiments, the one or more cuts may extend into the anode channel to a depth ranging from about ⅛ to about ½ of the thickness of the anode channel. In some embodiments, the depth is at least about ⅛, about ⅙, about ⅙, about ⅙, about ⅕, about ¼, about ⅓, about ½, or any value therebetween of the thickness of the anode channel. In some embodiments, the depth is at most about ⅛, about ⅙, about ⅙, about ⅙, about ⅕, about ¼, about ⅓, about ½, or any value therebetween of the thickness of the anode channel. In some embodiments, the depth is ⅛ to about ½, about ⅙ to about ⅙, about ⅙ to about ⅓, about ⅙ to about ⅓, about ⅙ to about ⅓, about ⅙ to about ⅓, or about ⅙ to about ½ of the thickness of the anode channel. For example, in an anode channel having a thickness of 2 mm, the cuts may have a depth ranging from about 0.25 mm to about 1 mm.

[0303] In some embodiments, the one or more cuts may extend into the anode channel to a depth ranging from about 1 / 2 to about 4 / 5 of the thickness of the anode channel. In some embodiments, the depth is at least about 1 / 2, about 2 / 3, about 3 / 4, about 4 / 5, or any value therebetween, of the thickness of the anode channel. In some embodiments, the depth is at most about 1 / 2, about 2 / 3, about 3 / 4, about 4 / 5, or any value therebetween, of the thickness of the anode channel. In some embodiments, the depth is 1 / 2 to about 4 / 5, about 2 / 3 to about 3 / 4, or about 3 / 4 to about 4 / 5 of the thickness of the anode channel. For example, in an anode channel having a thickness of 2 mm, the cuts may have a depth ranging from about 1 mm to about 1.6 mm.

[0304] In some cases, some of the one or more cuts may extend into the anode channel to a different depth than others of the one or more cuts (e.g., a first set of cuts may have a depth of 0.25 mm and a second set of cuts may have a depth of 0.5 mm). In some cases, each of the one or more cuts may extend into the anode channel to the same depth.

[0305] In some cases, the fuel cell comprises an anode gas diffusion layer having one or more anode channels. In some embodiments, the one or more anode channels comprise one or more features. In some embodiments, the one or more features comprise (i) one or more cuts or grooves, or (ii) one or more cutouts or openings, configured to enhance diffusion and transport of feed materials through the anode gas diffusion layer. In some embodiments, the one or more features are configured to direct the flow of nitrogen from the anode gas diffusion layer out of the fuel cell such that nitrogen does not accumulate in the anode gas diffusion layer.

[0306] In some embodiments, one feature of the one or more features has a depth that is at least about 0.01 mm, about 0.05 mm, about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value therebetween. In some embodiments, the depth is at most about 0.01 mm, about 0.05 mm, about 0.1 mm, about 0.2 mm, about 0.3 mm, about 0.4 mm, about 0.5 mm, about 0.6 mm, about 0.7 mm, about 0.8 mm, about 0.9 mm, about 1 mm, about 2 mm, about 3 mm, about 4 mm, about 5 mm, about 6 mm, about 7 mm, about 8 mm, about 9 mm, about 10 mm, or any value therebetween. In some embodiments, the depth is 0.01 mm to about 10 mm, about 0.05 mm to about 9 mm, about 0.1 mm to about 8 mm, 0.2 mm to about 7 mm, about 0.3 mm to about 6 mm, about 0.4 mm to about 5 mm, 0.5 mm to about 4 mm, about 0.6 mm to about 3 mm, about 0.7 mm to about 2 mm, 0.8 mm to about 1 mm, or about 0.9 mm to about 10 mm.

[0307] In some cases, the cut structure may comprise one or more cuts extending across at least a portion of the surface of the anode channel. In some cases, the one or more cuts may be parallel to one another. In other cases, the one or more cuts may not be parallel to one another, and need not be parallel. In some cases, the cuts may comprise one or more horizontal cuts extending along the width of the anode channel and / or one or more vertical cuts extending along the length of the anode channel. The one or more horizontal cuts and the one or more vertical cuts may or may not intersect each other. In some cases, the surface of the anode channel may comprise one or more sets of cut structures. The one or more sets of cut structures may be disposed on different portions or regions of the surface of the anode channel. In some cases, the one or more sets of cut structures may be distributed across different quadrants of the surface of the anode channel. In some cases, the one or more cuts may be disposed at an angle relative to one another. In some cases, the one or more cuts may be disposed at a number of different angles relative to one another.

[0308] FIG. 12 illustrates various examples of cutout structures that can be utilized in the anode channel of a fuel cell. The cutout structure may include a plurality of cutouts (e.g., openings) across the surface of the anode channel of the fuel cell. The plurality of cutouts may include one or more cutouts in the surface of the anode channel to reduce nitrogen accumulation in the anode and promote nitrogen outflow from the fuel cell such that nitrogen does not accumulate in the gas diffusion layer of the anode. In some cases, the area ratio of the cutouts (the ratio of (i) the removed area of ​​the cutouts to (ii) the original area of ​​the anode channel surface, e.g., if 20% of the original area of ​​the surface is removed, the area ratio of the cutouts may be 0.2) may range from about 0.01 to about 0.5. In some cases, the area ratio of the cutouts may range from about 0.3 to about 0.7. In some cases, the area ratio of the cutouts may range from about 0.5 to about 0.9. In some embodiments, the area ratio of the cutout portion is at least about 0.01, about 0.05, about 0.1, about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, or any value therebetween. In some embodiments, the area ratio of the cutout portion is at most about 0.01, about 0.05, about 0.1, about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, or any value therebetween. In some embodiments, the area ratio of the cutout portion is 0.01 to about 0.9, about 0.05 to about 0.8, about 0.1 to about 0.7, 0.2 to about 0.6, about 0.3 to about 0.5, or about 0.4 to about 0.9.

[0309] In some cases, the cutout structure may comprise one or more cutouts extending across at least a portion of the surface of the anode channel. In some cases, the one or more cutouts may be parallel to one another. In other cases, the one or more cutouts may not be parallel to one another, and need not be parallel. In some cases, the cutouts may comprise one or more horizontal cutouts extending along the width of the anode channel and / or one or more vertical cutouts extending along the length of the anode channel. The one or more horizontal cutouts and the one or more vertical cutouts may or may not intersect with one another. In some cases, the surface of the anode channel may comprise one or more sets of cutout structures. The one or more sets of cutout structures may be disposed on different portions or regions of the surface of the anode channel. In some cases, the one or more sets of cutout structures may be distributed across different quadrants of the surface of the anode channel. In some cases, the one or more cutouts may be disposed at an angle relative to one another. In some cases, the one or more cutouts may be disposed at a number of different angles relative to one another.

[0310] In some embodiments, the one or more grooves may extend into the anode channel to a depth ranging from about ⅛ to about ½ of the thickness of the anode channel. In some embodiments, the depth is at least about ⅛, about ⅙, about ⅙, about ⅙, about ⅕, about ¼, about ⅓, about ½, or any value therebetween of the thickness of the anode channel. In some embodiments, the depth is at most about ⅛, about ⅙, about ⅙, about ⅙, about ⅕, about ¼, about ⅓, about ½, or any value therebetween of the thickness of the anode channel. In some embodiments, the depth is ⅛ to about ½, about ⅙ to about ⅙, about ⅙ to about ⅓, about ⅙ to about ⅓, about ⅙ to about ⅓, about ⅙ to about ⅓, or about ⅙ to about ½ of the thickness of the anode channel. For example, in an anode channel with a depth of 2 mm, the grooves may have a depth ranging from about 0.25 mm to about 1 mm. In some embodiments, the one or more grooves may extend into the anode channel to a depth ranging from about 1 / 2 to about 4 / 5 of the thickness of the anode channel. In some embodiments, the depth is at least about 1 / 2, about 2 / 3, about 3 / 4, about 4 / 5, or any value therebetween, of the thickness of the anode channel. In some embodiments, the depth is at most about 1 / 2, about 2 / 3, about 3 / 4, about 4 / 5, or any value therebetween, of the thickness of the anode channel. In some embodiments, the depth is 1 / 2 to about 4 / 5, about 2 / 3 to about 3 / 4, or about 3 / 4 to about 4 / 5 of the thickness of the anode channel.

[0311] In some cases, the groove or grooves may extend into the anode channel at a depth different from the thickness of the anode channel. For example, in an anode channel with a depth of 2 mm, the grooves may have a depth in the range of about 1 mm to about 1.6 mm. In some cases, the groove or grooves may extend into the anode channel at a depth equal to the thickness of the anode channel. In some cases, the area ratio of the grooves (ratio of the area of ​​the grooves to the original area of ​​the anode channel surface, e.g., if 20% of the original area constitutes the grooves, the area ratio of the grooves may be 0.2) may be in the range of about 0.01 to about 0.5. In some cases, the area ratio of the grooves may be in the range of about 0.3 to about 0.7. In some cases, the area ratio of the grooves may be in the range of about 0.5 to about 0.9. In some embodiments, the area ratio of the groove is at least about 0.01, about 0.05, about 0.1, about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, or any value therebetween. In some embodiments, the area ratio of the groove is at most about 0.01, about 0.05, about 0.1, about 0.2, about 0.3, about 0.4, about 0.5, about 0.6, about 0.7, about 0.8, about 0.9, or any value therebetween. In some embodiments, the area ratio of the groove is 0.01 to about 0.9, about 0.05 to about 0.8, about 0.1 to about 0.7, 0.2 to about 0.6, about 0.3 to about 0.5, or about 0.4 to about 0.9.

[0312] In some cases, the anode channel may include one or more cuts extending across at least a portion of the surface of the anode channel, one or more cutouts extending across at least a portion of the surface of the anode channel, one or more grooves extending across at least a portion of the surface of the anode channel, or any combination of cuts, cutouts and grooves.

[0313] In some cases, cuts may be preferred where a minimum cutout area ratio is preferred. In some cases, cutouts or grooves, or a combination thereof, may be preferred to achieve higher nitrogen purge rates (e.g., compared to cuts alone, which may achieve relatively low nitrogen purge rates).

[0314] In some cases, where a minimum cutout area ratio or a minimum groove area ratio is preferred, a combination of one or more cuts, one or more cutouts, or one or more grooves may be used. In some cases, the minimum cutout area ratio or groove area ratio may be less than 0.1. In some cases, the minimum cutout or groove area ratio may be less than 0.2. In some cases, the minimum cutout or groove area ratio may be less than 0.5.

[0315] In some cases, the anode channel may include both cuts and cutouts that extend into the anode channel to the same depth. In some cases, the anode channel may include both cuts and cutouts that extend into the anode channel to different depths.

[0316] In some cases, the cuts, cutouts, and grooves may be manufactured using one or more methods including at least one of stamping, laser cutting, engraving, chemical etching, and embossing. In some cases, material removed by the cutouts can be recycled and used to form one or more channels in one or more fuel cells.

[0317] In some cases, the fuel cell comprises a plurality of channels in fluid communication with the anode. The plurality of channels can be stacked in layers adjacent to each other. FIG. 6 illustrates various examples of multi-layer anode channel structures that can be implemented to improve the performance of a fuel cell when the fuel cell is used to process a gas mixture of hydrogen and nitrogen to produce electrical energy. The multi-layer anode channel may comprise a plurality of layers. The plurality of layers can comprise at least a first layer and a second layer. At least one of the first layer and the second layer may comprise one or more cuts and / or one or more cutouts. In some cases, the first layer of the plurality of layers may not comprise any cuts or cutouts. In such cases, the second layer of the plurality of layers may comprise one or more cuts and / or one or more cutouts. In some cases, each of the first layer and the second layer may comprise one or more cuts and / or one or more cutouts. The cuts or cutouts of the first layer may be aligned with the cuts or cutouts of the second layer, or may not be aligned with either. In some cases, the first layer may include a first set of cuts or cutouts and the second layer may include a second set of cuts or cutouts. The first and second sets of cuts or cutouts may or may not overlap one another. In some cases, the first and second sets of cuts or cutouts may include different patterns of cuts or cutouts. In some cases, the first and second sets of cuts or cutouts may include a combination of horizontal and vertical cuts or cutouts. In some cases, the first set of cuts or cutouts may include a plurality of horizontal cuts or cutouts and the second set of cuts or cutouts may include a plurality of vertical cuts or cutouts.In some cases, the first set of cuts or cutouts may comprise a plurality of perpendicular cuts or cutouts and the second set of cuts or cutouts may comprise a plurality of perpendicular cuts or cutouts. At least one channel of the plurality of channels may be completely free of (i.e., devoid of) features comprising cuts, cutouts, and / or grooves.

[0318] As noted above, in some cases, the cut(s) and / or cutout(s) may extend across at least a portion of the surface of the anode channel. In some cases, the cut(s) and / or cutout(s) may be parallel to one another. In other cases, the cut(s) and / or cutout(s) may not be or need not be parallel to one another. In some cases, the cut(s) and / or cutout(s) may comprise one or more horizontal cuts or cutouts extending along the width of the anode channel and / or one or more vertical cuts or cutouts extending along the length of the anode channel. The horizontal cut(s) and the vertical cut(s) may or may not intersect each other. In some cases, the surface of the anode channel may comprise one or more sets of cut or cutout structures. The set(s) of cut or cutout structures may be disposed on different portions or regions of the surface of the anode channel. In some cases, one or more sets of cut or cutout structures may be distributed across different quadrants of the surface of the anode channel. In some cases, one or more cuts or cutouts may be disposed at an angle relative to one another. In some cases, one or more cuts or cutouts may be disposed at a number of different angles relative to one another. In some cases, the one or more surface features may comprise one or more cuts or grooves on the surface of the one or more anode channels. The one or more cuts or grooves may extend across a portion of the surface of the one or more anode channels. In some cases, the one or more cuts or grooves may comprise two or more cuts or grooves that are parallel to one another. In other cases, the one or more cuts or grooves may comprise two or more cuts or grooves that are perpendicular to one another.In some cases, the one or more cuts or grooves may comprise two or more cuts or grooves disposed at an angle relative to one another. The angle may range from 0 degrees to about 90 degrees. In some cases, the angle may range from 0 degrees to about 45 degrees. In some cases, the angle may range from 0 degrees to about 30 degrees. In some cases, the angle may range from 0 degrees to about 15 degrees. In some cases, the one or more cuts or grooves may comprise two or more cuts or grooves that intersect with one another. In other cases, the one or more cuts or grooves may comprise two or more cuts or grooves that do not intersect.

[0319] In some cases, the one or more surface features may comprise one or more cutouts or openings on a surface of the one or more channels. The one or more cutouts or openings may extend across a portion of a surface of the one or more channels. In some cases, the one or more cutouts or openings may comprise two or more cutouts or openings that are parallel to one another. In other cases, the one or more cutouts or openings may comprise two or more cutouts or openings that are perpendicular to one another. In some cases, the one or more cutouts or openings may comprise two or more cutouts or openings that are disposed at an angle relative to one another. The angle may range from 0 degrees to about 90 degrees. In some cases, the angle may range from 0 degrees to about 45 degrees. In some cases, the angle may range from 0 degrees to about 30 degrees. In some cases, the angle may range from 0 degrees to about 15 degrees. In some cases, the one or more cutouts or openings may comprise two or more cuts or grooves that intersect with one another. In other cases, the one or more cutouts or openings may comprise two or more cutouts or openings that do not intersect.

[0320] In some embodiments, the anode gas diffusion layer may comprise one or more layers. In some cases, the one or more layers may comprise two or more layers. At least one layer of the two or more layers may comprise one or more surface features. The one or more surface features may comprise (i) one or more cuts or grooves, and / or (ii) one or more cutouts or openings. In some cases, the two or more layers may comprise a first layer comprising a first set of surface features and a second layer comprising a second set of surface features. In some cases, the first set of features and the second set of features may comprise the same or similar sets of features. In other cases, the first set of features and the second set of features may comprise different sets of features. In some cases, the first set of features and the second set of features may overlap or partially overlap. In other cases, the first set of features and the second set of features may not overlap or need not overlap.

[0321] In some cases, the anode gas diffusion layer may include a felt, foam, cloth, or paper material. The felt, foam, cloth, or paper material may include, for example, graphite or another carbon-based material (e.g., carbon fiber). In some cases, the felt, foam, cloth, or paper material may include a carbon felt that may have a form, property, or characteristic similar to a cotton material. Alternatively, the felt, foam, cloth, or paper material may include a carbon paper that may have a form, property, or characteristic similar to a sheet of paper. In some cases, the felt, foam, cloth, or paper material may include a polytetrafluoroethylene (PTFE)-based material. In some cases, the felt, foam, cloth, or paper material may include both a carbon-based material and a PTFE-based material. In some cases, the felt, foam, cloth, or paper material may have a hydrophobic property with a water contact angle of more than about 90 degrees. In some cases, the felt, foam, cloth, or paper material may have a hydrophilic property with a water contact angle of less than about 90 degrees. In some cases, at least a portion of the felt, foam, cloth, or paper material may be hydrophobic and at least one other portion of the felt, foam, cloth, or paper material may be hydrophilic. The felt, foam, cloth, or paper material may be porous and may have different properties, such as porosity, pore size, density, brittleness, and flexibility. In some cases, the felt, foam, cloth, or paper material may be capable of conducting electrical current. In some cases, the felt, foam, cloth, or paper material may have at least one of a different surface texture, porosity, or pore size between the first side and the second side. In some cases, the first side is a front or top side and the second side is a bottom or back side. In some cases, the first side faces the electrolyte and the second side faces the exterior of the fuel cell. In some cases, a denser material may improve the performance of the anode gas diffusion layer. In some cases, a material that is too dense may increase gas diffusion or transport resistance. In some cases, thinner materials may improve the performance of the anode gas diffusion layer by reducing gas diffusion or transport resistance.In some cases, thinner materials are preferred to increase the power density of the fuel cell. In some cases, a material that is too thin may increase gas diffusion or transport resistance. It is noted herein that the anode diffusion layer may include materials other than felt, foam, paper, cloth, carbon-based materials, and PTFE-based materials.

[0322] If a single layer structure is utilized, the material for the gas diffusion layer may need to be porous to allow hydrogen to diffuse through the gas diffusion layer. If a multi-layer structure is utilized, the membrane side of the gas diffusion layer may comprise a porous sheet material, and the current collecting side (where the channels are located) may comprise any conductive sheet material, such as metal, copper, nickel, zinc, platinum, aluminum, steel, titanium, gold, or a carbon-based material. In some cases, the conductive sheet may comprise any conductive sheet material having one or more coatings of different conductive materials.

[0323] In some cases, the felt, foam, cloth, or paper material may include carbon paper, which can be produced by burning a carbon-based polymer sheet. The carbon felt, foam, cloth, or paper material may not or need not include a crystalline structure.

[0324] Fuel cell outlet flow

[0325] In some cases, the outlet stream can be from one or more fuel cells. The outlet stream from the fuel cell can include H2, N2, O2, and / or one or more reaction by-products (e.g., water). The outlet stream from the anode channel can include H2, N2, ammonia (e.g., trace ammonia from ammonia reforming), water, or any combination thereof. The outlet stream from the cathode channel can include O2, N2, water, or any combination thereof. In some cases, the fuel cell outlet stream can include unconverted hydrogen from the fuel cell (hydrogen that is not consumed by the fuel cell and is not converted to protons and electrons at the electrolyte membrane). In some cases, the fuel cell outlet stream can include unconverted hydrogen (anode exhaust gas) from the outlet stream of the anode channel of the fuel cell. In some cases, the unconverted hydrogen can be returned to one or more reactors for combustion heating to heat the reactor for further ammonia decomposition. In some cases, the outlet stream of the fuel cell can include unconverted hydrogen from the fuel cell, unconverted ammonia from the reactor, or unadsorbed ammonia from the adsorption tower. In some cases, unconverted hydrogen from the fuel cell and unconverted or unadsorbed ammonia from the reactor or adsorption tower may be returned to the reactor(s) for combustion heating to heat the reactor(s) for further ammonia decomposition. In some cases, unconverted O2 from the outlet stream of the cathode channel may be directed to the reactor(s) for combustion heating to heat the reactor(s) for ammonia decomposition.

[0326] In some cases, the stream exiting the one or more fuel cells can contain a volume fraction, mole fraction, or partial pressure fraction of hydrogen of at most about 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. In some cases, the stream exiting the one or more fuel cells can contain hydrogen in a volume fraction, mole fraction, or partial pressure fraction in the range of at least about 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.5 to 0.8. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.4 to 0.7. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.3 to 0.6. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.2 to 0.5. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.1 to 0.4. In some cases, the stream exiting the one or more fuel cells may include hydrogen at a volume fraction, molar fraction, or partial pressure fraction in the range of 0.05 to 0.3.In some cases, the stream exiting one or more fuel cells may contain a volume fraction, mole fraction, or partial pressure fraction of hydrogen in the range of 0.3 to 0.4.

[0327] In some cases, the stream exiting the one or more fuel cells may contain nitrogen in a volume fraction, mole fraction, or partial pressure fraction in a range of up to about 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 0.991, 0.992, 0.993, 0.994, 0.995, 0.996, 0.997, 0.998, or 0.999. In some cases, the stream exiting the one or more fuel cells has a volume fraction, mole fraction, or partial pressure fraction of at least about 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03 , 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.91, 0.92, 0.93, 0.94, 0.95, 0.96, 0.97, 0.98, 0.99, 0.991, 0.992, 0.993, 0.994, 0.995, 0.996, 0.997, 0.998, or 0.999 of nitrogen. In some cases, the stream exiting the one or more fuel cells can include a nitrogen volume fraction, mole fraction, or partial pressure fraction in the range of 0.1 to 0.4. In some cases, the stream exiting the one or more fuel cells can include a nitrogen volume fraction, mole fraction, or partial pressure fraction in the range of 0.3 to 0.6. In some cases, the stream exiting the one or more fuel cells can include nitrogen at a volume fraction, mole fraction, or partial pressure fraction in the range of 0.5 to 0.8. In some cases, the stream exiting the one or more fuel cells can include nitrogen at a volume fraction, mole fraction, or partial pressure fraction in the range of 0.6 to 0.9. In some cases, the stream exiting the one or more fuel cells can include nitrogen at a volume fraction, mole fraction, or partial pressure fraction in the range of 0.4 to 0.6.In some cases, the stream exiting the one or more fuel cells may include at least two of hydrogen, nitrogen, water, or oxygen.

[0328] In some cases, the stream exiting the one or more fuel cells can contain ammonia in a volume fraction, mole fraction, or partial pressure fraction in the range of up to about 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9. In some cases, the stream exiting the one or more fuel cells can contain ammonia in a volume fraction, mole fraction, or partial pressure fraction in the range of at least about 0.0001, 0.0002, 0.0003, 0.0004, 0.0005, 0.0006, 0.0007, 0.0008, 0.0009, 0.001, 0.002, 0.003, 0.004, 0.005, 0.006, 0.007, 0.008, 0.009, 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0329] In some cases, the multiple streams including unconverted hydrogen may exit one or more fuel cells, one or more fuel cell stacks, or one or more fuel cell modules. In some cases, the multiple streams exiting one or more fuel cells, one or more fuel cell stacks, or one or more fuel cell modules may be directed to one or more fired heaters of an ammonia reformer. In some cases, the multiple streams exiting one or more fuel cells, one or more fuel cell stacks, or one or more fuel cell modules have at least one stream that differs in flow rate, mole fraction of hydrogen, mole fraction of nitrogen, or mole fraction of water from other exit streams. In some cases, the multiple streams exiting one or more fuel cells, one or more fuel cell stacks, or one or more fuel cell modules include flow rates within a tolerance range that is selected based on a target flow rate (e.g., a target flow rate to a single fuel cell, fuel cell stack, or fuel cell module). In some cases, the selected tolerance range is at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, or 500%. In some cases, the selected tolerance range is up to about 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 200, 300, 400, or 500%.

[0330] In some cases, one or more streams exiting the fuel cell(s), fuel cell stack(s), or fuel cell module(s) may pass through one or more water collectors or water condensers. In some cases, the one or more water collectors or water condensers remove at least a portion of the water of the one or more streams exiting the fuel cell(s), fuel cell stack(s), or fuel cell module(s). In some cases, the one or more water collectors or water condensers remove at least a portion of the water of the one or more streams exiting the fuel cell(s), fuel cell stack(s), or fuel cell module(s) and then provide the one or more streams exiting the fuel cell(s), fuel cell stack(s), or fuel cell module(s) to one or more fired heaters of an ammonia reformer. In some cases, one or more streams exiting the fuel cell(s), fuel cell stack(s), or fuel cell module(s) include H2, N2, water, or O2.

[0331] Computer Systems In one aspect, the present disclosure provides a computer system programmed or configured to implement the methods of the present disclosure. FIG. 14 shows a computer system 1401 programmed or configured to implement a method for processing hydrogen and / or a mixture of hydrogen and nitrogen. In some embodiments, the computer system is configured to operate a fuel cell to enable purging of nitrogen from the fuel cell while the fuel cell is generating electricity. In some embodiments, the computer system is configured to operate the fuel cell to enable continuous purging of nitrogen. The computer system 1401 can be configured, for example, to (i) control the flow of feed material, including hydrogen and nitrogen, to one or more fuel cells and (ii) control the operation of one or more fuel cells that process the feed material to generate electricity (e.g., electrical current). The computer system 1401 can be a user's electronic device or a computer system located remotely relative to the electronic device. The electronic device can be a mobile electronic device.

[0332] The computer system 1401 may include a central processing unit (CPU, also referred to herein as "processor" and "computer processor") 1405, which may be a single-core or multi-core processor, or multiple processors for parallel processing. The computer system 1401 may also include memory or storage locations 1410 (e.g., random access memory, read-only memory, flash memory), electronic storage 1415 (e.g., hard disk), communication interface 1420 (e.g., network adapter) for communicating with one or more other systems, and peripherals 1425, such as cache, other memory, data storage, and / or electronic display adapters. The memory 1410, storage 1415, interface 1420, and peripherals 1425 communicate with the CPU 1405 via a communication bus (solid lines), e.g., a motherboard. The storage 1415 may be a data storage device (or data repository) for storing data. The computer system 1401 may be operatively coupled to a computer network ("network") 1430 using the communication interface 1420. The network 1430 can be the Internet, an Internet and / or an extranet, or an intranet and / or an extranet in communication with the Internet. In some cases, the network 1430 is a telecommunications network and / or a data network. The network 1430 can include one or more computer servers, which can enable distributed computing, such as cloud computing. The network 1430 can, in some cases, implement a peer-to-peer network using the computer system 1401, whereby devices coupled to the computer system 1401 can operate as clients or servers.

[0333] The CPU 1405 can execute a series of machine-readable instructions, which may be embodied in a program or software. The instructions may be stored in a memory location, such as the memory 1410. The instructions can be directed to the CPU 1405, which can then be programmed or configured to perform the methods of the present disclosure. Examples of operations performed by the CPU 1405 can include fetch, decode, execute, and writeback.

[0334] The CPU 1405 may be part of a circuit, such as an integrated circuit. One or more other components of the system 1401 may be included in the circuit. In some cases, the circuit is an application specific integrated circuit (ASIC).

[0335] The storage device 1415 can store files, such as drivers, libraries, and saved programs. The storage device 1415 can store user data, such as user settings and user programs. The computer system 1401 can optionally include one or more other data storage devices located external to the computer system 1401 (e.g., on a remote server in communication with the computer system 1401 via an intranet or the Internet).

[0336] The computer system 1401 can communicate with one or more remote computer systems via the network 1430. For example, the computer system 1401 can communicate with a remote computer system of a user (e.g., an individual who operates a reactor in which feedstock materials including hydrogen and nitrogen are made, an operator who monitors the operation of the reactor or one or more fuel cells operatively coupled to the reactor, or an end user who operates a device or vehicle that can be powered using electrical energy derived or generated from feedstock materials using one or more fuel cells). Examples of remote computer systems include a personal computer (e.g., a portable PC), a slate or tablet PC (e.g., Apple® iPad®, Samsung® Galaxy Tab), a phone, a smartphone (e.g., Apple® iPhone®, Android®-enabled devices, Blackberry®), or a personal digital assistant. A user can access the computer system 1401 via the network 1430.

[0337] The methods described herein can be performed by machine (e.g., a computer processor) executable code stored in an electronic storage location of the computer system 1401, such as memory 1410 or electronic storage 1415. The machine executable or machine readable code can be provided in the form of software. In use, the code can be executed by the processor 1405. In some cases, the code can be retrieved from storage 1415 and stored in memory 1410 for ready access by the processor 1405. In some cases, the electronic storage 1415 can be excluded and the machine executable instructions are stored in memory 1410.

[0338] The code can be precompiled and configured for use on a machine having a processor configured to execute the code, or it can be compiled on the fly. The code can be provided in a programming language, which can be selected so that the code can be executed in a precompiled or compiled form.

[0339] Aspects of the systems and methods provided herein, such as the computer system 1401, can be embodied in programming. Various aspects of the technology can be thought of as a "product" or "article of manufacture," typically in the form of machine (or processor) executable code and / or associated data carried on or embodied in a type of machine-readable medium. The machine-executable code can be stored on an electronic storage device, such as a memory (e.g., read-only memory, random access memory, flash memory) or a hard disk. A "storage" type medium may include any or all of the tangible memory of a computer, a processor, etc., or their associated modules, such as various semiconductor memories, tape drives, disk drives, etc., which can provide non-transitory storage at any time for software programming. All or parts of the software may sometimes be communicated over the Internet or various other communication networks. Such communication can, for example, allow the software to be loaded from one computer or processor to another, for example, from a management server or host computer to the computer platform of an application server. Thus, other types of media that may carry software elements include the optical, electrical, and electromagnetic waves used across physical interfaces between local devices, over wired and optical landline networks, and over various air links. The physical elements that transmit such waves, e.g., wired or wireless links, optical links, etc., may also be considered media carrying the software. As used herein, unless limited to non-transitory, tangible "storage" media, the term, e.g., computer or machine "readable medium," refers to any medium that participates in providing instructions to a processor for execution.

[0340] Thus, the machine-readable medium, e.g., computer executable code, can take many forms, including but not limited to tangible storage media, carrier wave media, or physical transmission media. For example, non-volatile storage media, including optical or magnetic disks, or any storage device, such as any computer, may be used to implement the databases, etc., shown in the figures. Volatile storage media include dynamic memory, e.g., main memory of such a computer platform. Tangible transmission media include coaxial cables, copper wire, and fiber optics, including wiring, including a bus within a computer system. Carrier wave transmission media may take the form of electric or electromagnetic signals, or acoustic or light waves, such as those generated during radio frequency (RF) and infrared (IR) communications. Thus, common forms of computer readable media include, for example, floppy disks, flexible disks, hard disks, magnetic tape, any other magnetic media, CD-ROMs, DVDs or DVD-ROMs, any other optical media, punched card paper tape, any other physical storage media with a pattern of holes, RAM, ROM, PROMs and EPROMs, FLASH-EPROMs, any other memory chips or cartridges, carrier waves transmitting data or instructions, cables or links transmitting such carrier waves, or any other medium from which a computer can read programming code and / or data. Many of these forms of computer readable media may be involved in transmitting one or more sequences of one or more instructions to a processor for execution.

[0341] The computer system 1401 may include or communicate with an electronic display 1435 that includes a user interface (UI) 1440 to provide, for example, a portal for a user to monitor or track the operation or performance of the one or more fuel cells. In some cases, the performance of the one or more fuel cells may include, for example, the voltage of the current generated using the one or more fuel cells. The portal may be provided through an application programming interface (API). A user or operator may also interact with various elements in the portal through the UI. Examples of UIs include, but are not limited to, graphical user interfaces (GUIs) and web-based user interfaces.

[0342] The methods and systems of the present disclosure may be implemented by one or more algorithms. The algorithms may be implemented by software when executed by the central processing unit 1405. For example, the algorithms may be configured to control the operation of one or more fuel cells based on one or more sensor measurements (e.g., temperature measurements, flow rates, etc.), based on power demand, or based on the performance of one or more fuel cells. The algorithms may be configured to operate the fuel cells to allow for purging of nitrogen from the fuel cells while the fuel cells are generating power, or to operate the fuel cells to allow for continuous purging of nitrogen.

[0343] vehicle In some cases, the one or more fuel cells can be adapted for use in an air vehicle. The air vehicle can include, for example, a manned air vehicle, an unmanned air vehicle, or a drone. In some cases, the fuel cell can be integrated into the body of the air vehicle. In other cases, the fuel cell may be located on top of or underneath the body of the air vehicle. In some cases, the fuel cell may be electrically coupled to a motor or engine of the air vehicle.

[0344] In some cases, the one or more fuel cells may be adapted for use in a land vehicle, e.g., a car, an agricultural vehicle, or an automobile. The one or more fuel cells may be located at or near the front of the land vehicle (e.g., in an engine bay of the vehicle). The one or more fuel cells may be located at or near an underside region of the land vehicle. The one or more fuel cells may be located near the rear of the land vehicle. In some cases, the one or more fuel cells may be located near the axles of the ground vehicle (e.g., the front and / or rear axles of the vehicle). In some cases, the fuel cell may be electrically coupled to a motor or engine of the land vehicle.

[0345] In some cases, the fuel cell or fuel cells may be adapted for use in a land vehicle, such as a truck or semi-trailer truck. In some cases, the fuel cell or fuel cells may be coupled to or incorporated into the rear of a tractor unit of a truck. A tractor unit (also known as a prime mover, truck, truck trailer, semi-tractor, rig, big rig, or simply tractor) may include a heavy-duty traction engine that provides power to haul loads to be towed or trailered. In some cases, the fuel cell or fuel cells may be located in or near the front of the tractor unit (e.g., in the engine compartment of the tractor unit). In other cases, the fuel cell or fuel cells may be located in or near the underside region of the tractor unit. In some cases, multiple fuel cells may be distributed along the underside of the tractor unit. In some cases, the fuel cell or fuel cells may be located near the axles (e.g., the front axles) of the tractor unit.

[0346] In some cases, the one or more fuel cells can be adapted for use in a marine vehicle. Examples of marine vehicles include manned vessels, unmanned vessels, boats, or ships. In some cases, the fuel cells can be incorporated within the body of the marine vehicle. In other cases, the fuel cells can be located on top of or under the body of the marine vehicle. In some cases, the fuel cells can be electrically coupled to a motor or engine of the marine vehicle. In some cases, the fuel cells can provide backup power for the marine vehicle. In some cases, the one or more fuel cells can be adapted for use in a submarine vehicle. In some cases, the fuel cells can be electrically coupled to a motor or engine of the submarine vehicle.

[0347] In some cases, the vehicle may include multiple fuel cells. In some cases, the multiple fuel cell modules may be positioned adjacent to each other. In other cases, the multiple fuel cell modules may be located apart from each other (i.e., on or in different faces, areas, or portions of the vehicle). In some cases, the multiple fuel cell modules may be oriented in the same direction. In other cases, at least two of the multiple fuel cell modules may be oriented in different directions. In any of the embodiments described herein, the multiple fuel cell modules may be appropriately positioned and / or oriented to maximize volumetric efficiency and minimize the physical footprint of the multiple fuel cell modules. In any of the embodiments described herein, the multiple fuel cell modules may be positioned and / or oriented to conform to the size and / or shape of the vehicle in which the fuel cell modules are positioned or provided. In any of the embodiments described herein, the multiple fuel cell modules may be positioned and / or oriented to conform to the size and / or shape of the vehicle in which the fuel cell modules are coupled or attached.

[0348] In any of the embodiments described herein, the fuel cell modules may be positioned at or on different faces, areas, or portions of the vehicle. The fuel cell modules may be appropriately positioned and / or oriented to maximize the volumetric efficiency and minimize the physical footprint of the fuel cell modules. The fuel cell modules may be positioned and / or oriented to conform to the size and / or shape of the vehicle in which the fuel cell modules are positioned or provided. The fuel cell modules may be positioned and / or oriented to conform to the size and / or shape of the vehicle in which the fuel cell modules are coupled or attached.

[0349] Numbered embodiments EMBODIMENT 1 1. A method for generating electricity using a fuel cell comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer being in fluid communication with a fuel cell, the fuel cell having an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, and a first channel having a first inlet and a first outlet, the first channel being in fluid communication with the anode, the first channel being configured to: (i) increase the hydrogen consumption rate of the fuel cell, or (ii) increase the output voltage of the fuel cell at the same hydrogen consumption rate, when the first continuous stream contacts the anode, compared to a comparable fuel cell without any features. 16. A method of reacting a fuel cell comprising: a first channel having one or more features, the one or more features comprising: (1) one or more cuts, (2) one or more cutouts, (3) one or more grooves, or (4) any combination thereof; and a second channel having a second inlet and a second outlet, the second channel in fluid communication with a cathode, the method comprising: directing a first continuous stream into the first channel via the first inlet such that the hydrogen contacts the anode; directing a second continuous stream including oxygen via the second inlet into the second channel such that the oxygen contacts the cathode; and reacting the hydrogen and oxygen to generate electricity using the fuel cell.

[0350] EMBODIMENT 2 2. The method of embodiment 1, wherein the one or more features increase the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode, as compared to a comparable fuel cell lacking any of the features.

[0351] EMBODIMENT 3 3. The method of embodiment 2, wherein the one or more forms increase the rate of hydrogen consumption by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0352] EMBODIMENT 4 4. The method of embodiment 2 or 3, wherein the one or more forms increase the rate of hydrogen consumption by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0353] EMBODIMENT 5 5. The method of any one of embodiments 1-4, wherein the one or more features increase the output voltage at the same hydrogen consumption rate when the first continuous flow contacts the anode, compared to a comparable fuel cell lacking any features.

[0354] EMBODIMENT 6 6. The method of embodiment 5, wherein the one or more features increase the voltage by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0355] EMBODIMENT 7 7. The method of embodiment 5 or 6, wherein the one or more forms increase the rate of hydrogen consumption by up to 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0356] EMBODIMENT 8 8. The method of any one of the preceding embodiments, wherein one or more configurations continuously purge nitrogen from the fuel cell.

[0357] EMBODIMENT 9 9. The method of embodiment 8, wherein nitrogen is continuously purged from the first channel by the one or more features such that nitrogen accumulation is reduced within the first channel, thereby increasing the hydrogen consumption rate compared to a comparable fuel cell lacking any features.

[0358] EMBODIMENT 10 10. The method of any one of the preceding embodiments, wherein the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode is at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0359] EMBODIMENT 11 11. The method of any one of the preceding claims, wherein the hydrogen consumption rate of the fuel cell when the first continuous stream contacts the anode is at most about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0360] EMBODIMENT 12 12. The method of any one of the preceding claims, further comprising intermittently reducing the hydrogen consumption rate to purge at least one of hydrogen, nitrogen, or water.

[0361] EMBODIMENT 13 13. The method of any one of the preceding embodiments, further comprising reducing the hydrogen consumption rate and directing at least a portion of the first continuous stream to an ammonia reformer.

[0362] EMBODIMENT 14 14. The method of any one of the preceding embodiments, further comprising: reducing a hydrogen consumption rate of the fuel cell to zero; and directing at least a portion of the first continuous stream to an ammonia reformer.

[0363] EMBODIMENT 15 15. The method of embodiment 13 or 14, further comprising combusting at least a portion of the first continuous stream directed to the ammonia reformer in one or more combustion exhausts of the one or more fired heaters, the one or more fired heaters in communication with the ammonia reformer to heat the ammonia reformer, and the one or more fired heaters in fluid communication with the fuel cell to receive at least a portion of the first continuous stream.

[0364] EMBODIMENT 16 1. A method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel having a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features being selected from the group consisting of (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) one or more recesses. ) a first channel having a first inlet and a second outlet, the second channel having a second inlet and a second outlet, the second channel being in fluid communication with a cathode; directing the first continuous flow into the first channel via the first inlet such that the hydrogen contacts the anode; directing a second continuous flow including oxygen into the second channel via the second inlet such that the oxygen contacts the cathode; and reacting the hydrogen and oxygen using the fuel cell to generate electricity, wherein the fuel cell has a ratio of power output of the fuel cell to projected surface area of ​​the anode of at least about 0.05 W / cm. 2 and reacting said first continuous stream comprising about 25 mole % nitrogen and about 75 mole % hydrogen and said second continuous stream comprising at least 20 mole % oxygen to obtain a mixture of said first continuous stream and said second continuous stream comprising at least 25 mole % nitrogen and about 75 mole % hydrogen.

[0365] EMBODIMENT 17 Ratios of at least about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm 2 17. The method of embodiment 16, wherein

[0366] EMBODIMENT 18 Ratios up to about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm 2 18. The method of embodiment 16 or 17, wherein

[0367] EMBODIMENT 19 19. The method of any one of examples 16-18, wherein the ratio is based on a first continuous stream comprising a hydrogen flow rate of at least about 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, or 100000 moles / second.

[0368] EMBODIMENT 20 20. The method of any one of embodiments 16-19, wherein the ratio is based on a second continuous stream comprising an oxygen flow rate of at least about 0.0001, 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000, 1000000 moles / second.

[0369] EMBODIMENT 21 21. The method of any one of embodiments 16 to 20, wherein the ratio is based on the second continuous flow comprising air.

[0370] EMBODIMENT 22 22. The method of any one of embodiments 16-21, wherein the ratio is based on a first continuous stream comprising hydrogen and nitrogen from an ammonia reformer.

[0371] EMBODIMENT 23 23. The method of any one of embodiments 16-22, wherein the anode projected surface area comprises the maximum possible surface area of ​​the anode projected onto a plane.

[0372] EMBODIMENT 24 24. The method of any one of embodiments 16-23, wherein the anode projected surface area comprises the surface area of ​​the largest surface of the anode.

[0373] EMBODIMENT 25 1. A method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel having a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof, the first channel comprising a first inlet and a second outlet. and a second channel having a second outlet, the second channel in fluid communication with the cathode; directing the first continuous stream into the first channel via the first inlet such that the hydrogen contacts the anode; directing a second continuous stream containing oxygen into the second channel via the second inlet such that the oxygen contacts the cathode; and reacting the hydrogen and oxygen using a fuel cell to generate power that is at least 50% of a reference power, wherein the reference power is generated using a fuel cell receiving a stream containing at least 99 mole % hydrogen into the first inlet, and the power is generated at the same current or the same hydrogen consumption rate as the reference power.

[0374] EMBODIMENT 26 26. The method of embodiment 25, wherein the power is at least 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0375] EMBODIMENT 27 27. The method of embodiment 25 or 26, wherein the power is up to 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0376] EMBODIMENT 28 1. A method for generating electricity using a fuel cell, comprising reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer in fluid communication with a fuel cell, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode, a first channel having a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more voids, (iv) one or more voids, (v) one or more voids, (vi) one or more voids, (vii) one or more voids, (v ... and (iv) a first channel having a depth of less than 10 mm, wherein the one or more features have a depth of less than 10 mm, and a second channel having a second inlet and a second outlet, wherein the second channel is in fluid communication with a cathode, the method comprising: directing a first continuous flow into the first channel via the first inlet such that the hydrogen contacts the anode; directing a second continuous flow including oxygen via the second inlet into the second channel such that the oxygen contacts the cathode; and reacting the hydrogen and oxygen to generate electricity using the fuel cell.

[0377] EMBODIMENT 29 29. The method of embodiment 28, wherein the one or more features have a depth of less than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0378] EMBODIMENT 30 30. The method of embodiment 28 or 29, wherein the one or more features have a depth of greater than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0379] EMBODIMENT 31 31. The method of any one of embodiments 28-30, wherein the depth is at least 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the first channel.

[0380] EMBODIMENT 32 32. The method of any one of embodiments 28-31, wherein the depth is at most 1 / 32, 1 / 16, 1 / 8, 1 / 4, 1 / 2, 3 / 4, 7 / 8, 15 / 16, or 31 / 32 of the thickness of the first channel.

[0381] EMBODIMENT 33 33. The method of any one of embodiments 28-32, wherein the first channel comprises a ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel that is at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0382] EMBODIMENT 34 34. The method of any one of embodiments 28 to 33, wherein the first channel has a ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel that is at most 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0383] EMBODIMENT 35 35. The method of any one of the preceding claims, wherein the one or more features comprises two or more features.

[0384] EMBODIMENT 36 36. The method of embodiment 35, wherein at least a first segment of a first feature of the two or more features is substantially parallel to a second segment of a second feature of the two or more features.

[0385] EMBODIMENT 37 36. The method of embodiment 35, wherein at least a first segment of a first feature of the two or more features is substantially perpendicular to a second segment of a second feature of the two or more features.

[0386] EMBODIMENT 38 36. The method of embodiment 35, wherein at least a first segment of a first feature of the two or more features is at an angle to a second segment of a second feature of the two or more features, the angle being between 0 and 90 degrees, between 15 and 75 degrees, between 0 and 30 degrees, or between 30 and 60 degrees.

[0387] EMBODIMENT 39 39. The method of any one of embodiments 35-38, wherein two or more features are linked.

[0388] EMBODIMENT 40 39. The method of any one of embodiments 35-38, wherein two or more features are separated.

[0389] EMBODIMENT 41 39. The method of any one of embodiments 35-38, wherein two or more features intersect.

[0390] EMBODIMENT 42 42. The method of any one of the preceding claims, wherein the one or more features comprise a serpentine shape.

[0391] EMBODIMENT 43 43. The method of any one of the preceding embodiments, wherein the one or more features are substantially parallel to the longest side of the first channel.

[0392] EMBODIMENT 44 43. The method of any one of the preceding embodiments, wherein the one or more features are substantially parallel to a shortest side of the first channel.

[0393] EMBODIMENT 45 45. The method of any one of embodiments 1-44, wherein the fuel cell comprises a plurality of channels in fluid communication with the anode, the plurality of channels comprising the first channel.

[0394] EMBODIMENT 46 46. ​​The method of embodiment 45, wherein the multiple channels comprise a stack of layers adjacent to one another.

[0395] EMBODIMENT 47 The method of embodiment 45 or 46, wherein at least one channel of the plurality of channels does not have any feature comprising (i) one or more cut portions, (ii) one or more cutout portions, (iii) one or more groove portions, or (iv) any combination thereof, or is completely absent.

[0396] EMBODIMENT 48 48. The method of any one of the preceding claims, wherein the one or more features are further configured to facilitate purging a selected material from the anode gas diffusion layer, the selected material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0397] EMBODIMENT 49 49. The method of embodiment 48, wherein the fuel cell further comprises one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0398] EMBODIMENT 50 50. The method of any one of the preceding claims, wherein the first channel comprises a felt, foam, cloth, or paper material.

[0399] EMBODIMENT 51 51. The method of embodiment 50, wherein the felt, foam, cloth, or paper material is a carbon-based material.

[0400] EMBODIMENT 52 52. The method of any one of the preceding embodiments, wherein the one or more features extend across at least a portion of a surface of the first channel.

[0401] EMBODIMENT 53 53. The method of any one of the preceding embodiments, wherein the electrolyte comprises a proton exchange membrane.

[0402] EMBODIMENT 54 54. The method of any one of the preceding embodiments, wherein the one or more features are configured to purge nitrogen from the fuel cell while the fuel cell is generating electricity.

[0403] EMBODIMENT 55 55. The method of any one of the preceding embodiments, wherein the ammonia concentration in the first continuous stream is at most 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0404] EMBODIMENT 56 56. The method of any one of the preceding embodiments, wherein the ammonia concentration in the first continuous stream is at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0405] EMBODIMENT 57 57. The method of any one of the preceding embodiments, wherein the one or more features increase the power density of the fuel cell by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0406] EMBODIMENT 58 58. The method of any one of the preceding embodiments, wherein the power density of the fuel cell is at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0407] EMBODIMENT 59 59. The method of any one of the preceding embodiments, wherein the power density of the fuel cell is at most about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0408] EMBODIMENT 60 60. The method of any one of the preceding embodiments, further comprising discharging a third continuous stream comprising unconverted hydrogen from the fuel cell.

[0409] EMBODIMENT 61 61. The method of embodiment 60, further comprising directing a third continuous stream comprising unconverted hydrogen to an ammonia reformer.

[0410] EMBODIMENT 62 62. The method of embodiment 61, further comprising combusting the unconverted hydrogen to heat the ammonia reformer.

[0411] EMBODIMENT 63 63. The method of embodiment 61 or 62, further comprising using one or more aeration units to supply at least oxygen to the ammonia reformer to combust unconverted hydrogen in the third continuous stream.

[0412] EMBODIMENT 64 64. The method of embodiment 62 or 63, further comprising removing water in the third continuous stream prior to combusting the unconverted hydrogen.

[0413] EMBODIMENT 65 61. The method of embodiment 60, further comprising combusting the third continuous stream.

[0414] EMBODIMENT 66 66. The method of any one of the preceding embodiments, wherein the first continuous stream comprises up to about 50, 60, 70, 80, 90, 95, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, or 99.9 mole percent hydrogen.

[0415] EMBODIMENT 67 67. The method of any one of the preceding embodiments, wherein the first continuous stream comprises at least about 50, 60, 70, 80, 90, 95, 99, 99.1, 99.2, 99.3, 99.4, 99.5, 99.6, 99.7, 99.8, or 99.9 mole percent hydrogen.

[0416] EMBODIMENT 68 68. The method of any one of the preceding embodiments, wherein the absolute pressure of the first continuous flow is at least about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar.

[0417] EMBODIMENT 69 69. The method of any one of the preceding embodiments, wherein the absolute pressure of the first continuous flow is at most about 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, or 40 bar.

[0418] EMBODIMENT 70 70. The method of embodiment 68 or 69, further comprising maintaining the absolute pressure of the first continuous stream within a tolerance of 1, 5, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, 110, 150, 200, 300, 400, 500, or 1000% of the absolute pressure.

[0419] EMBODIMENT 71 71. The method of any one of embodiments 68-70, further comprising adjusting the absolute pressure of the first continuous stream using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0420] EMBODIMENT 72 72. The method of embodiment 71, wherein one or more flow regulators, pressure regulators, control units, or any combination thereof are located upstream or downstream of the fuel cell.

[0421] EMBODIMENT 73 72. The method of embodiment 71, further comprising regulating the flow rate of the third continuous stream using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0422] EMBODIMENT 74 74. The method of embodiment 73, wherein one or more flow regulators, pressure regulators, control units, or any combination thereof are located upstream or downstream of the fuel cell.

[0423] EMBODIMENT 75 74. The method of embodiment 73, wherein one or more flow regulators, pressure regulators, control units, or any combination thereof are disposed downstream of the fuel cell to prevent backflow of unconverted hydrogen.

[0424] EMBODIMENT 76 76. The method of any one of the preceding embodiments, further comprising using the generated power to power one or more electrical devices.

[0425] EMBODIMENT 77 77. The method of any one of the preceding embodiments, further comprising using the generated power to power one or more electrical grids.

[0426] EMBODIMENT 78 78. The method of any one of the preceding embodiments, wherein the fuel cell comprises a plurality of fuel cells, and the ammonia reformer supplies a plurality of streams comprising hydrogen and nitrogen to the plurality of fuel cells.

[0427] EMBODIMENT 79 79. The method of any one of the preceding embodiments, further comprising directing unconverted hydrogen from the plurality of fuel cells to at least one ammonia reformer or reactor for combustion heating.

[0428] Embodiment 80 80. The method of embodiment 78 or 79, wherein at least one fuel cell of the plurality of fuel cells outputs a different power than other fuel cells of the plurality of fuel cells.

[0429] Embodiment 81 81. The method of any one of embodiments 78-80, wherein at least one fuel cell of the plurality of fuel cells is configured to reduce its power output.

[0430] EMBODIMENT 82 82. The method of any one of embodiments 78-81, further comprising adjusting the flow rate of the plurality of streams using one or more flow regulators, pressure regulators, control units, or any combination thereof.

[0431] EMBODIMENT 83 The method of any one of embodiments 78 to 82, wherein at least one fuel cell of the plurality of fuel cells receives one of the plurality of streams, the one stream having a flow rate different from the flow rates of the other streams of the plurality of streams.

[0432] EMBODIMENT 84 A method according to any one of embodiments 78 to 82, wherein each of the plurality of fuel cells receives one of the plurality of streams at a flow rate that is approximately the same as the other flow rates of the other streams of the plurality of streams or within a selected tolerance range of the other flow rates of the other streams.

[0433] EMBODIMENT 85 85. The method of embodiment 84, wherein the selected tolerance range is about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%.

[0434] EMBODIMENT 86 86. The method of any one of embodiments 78-85, wherein the plurality of fuel cells comprises at least one fuel cell that differs from the other fuel cells in size, power output, hydrogen consumption rate, power density, or operating temperature.

[0435] EMBODIMENT 87 1. A system comprising: an ammonia reformer configured to react ammonia to produce a first continuous stream comprising nitrogen and hydrogen; and a fuel cell in fluid communication with the ammonia reformer, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; and a first channel comprising a first inlet and a first outlet, the first channel comprising one or more features configured to (i) increase a hydrogen consumption rate or (ii) increase an output voltage at the same hydrogen consumption rate when the first continuous stream contacts the anode compared to a comparable fuel cell lacking any of the features, the one or more features being configured to include (i) one or more cuts, (ii) one or more cutouts, (iii) one or more cut-outs, (iv) one or more cut-outs, (v) one or more cut-outs, (vi) one or more cut-outs, (vii) one or more cut-outs, (viii ... or a plurality of channels, or (iv) any combination thereof; and a second channel with a second inlet and a second outlet, the second channel in fluid communication with a cathode; and a controller comprising at least one processor configured to execute executable instructions, the instructions executable by the controller configured to: react ammonia using an ammonia reformer to produce a first continuous stream comprising hydrogen and nitrogen; direct a second continuous stream comprising oxygen to the cathode of the fuel cell; and direct the first continuous stream to an anode of the fuel cell to react the hydrogen and oxygen to generate electricity.

[0436] EMBODIMENT 88 88. The system of embodiment 87, wherein the one or more features increase the hydrogen consumption rate of the fuel cell when the first continuous flow contacts the anode, compared to a comparable fuel cell lacking any features.

[0437] EMBODIMENT 89 89. The system of embodiment 88, wherein the one or more features increase the hydrogen consumption rate by at least 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0438] EMBODIMENT 90 90. The system of embodiment 88 or 89, wherein the one or more features increase the hydrogen consumption rate by up to 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0439] EMBODIMENT 91 A system as described in any one of embodiments 87 to 90, wherein the one or more features increase the output voltage at the same hydrogen consumption rate when the first continuous flow contacts the anode, compared to a comparable fuel cell lacking any features.

[0440] EMBODIMENT 92 92. The system of embodiment 91, wherein the one or more features increase the output voltage by at least 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200% at the same hydrogen consumption rate.

[0441] EMBODIMENT 93 93. The system of embodiment 91 or 92, wherein the one or more features increase the hydrogen consumption rate by up to 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0442] EMBODIMENT 94 The system of any one of embodiments 87-93, wherein the one or more configurations continuously purge nitrogen from the fuel cell.

[0443] EMBODIMENT 95 A system as described in any one of embodiments 87 to 94, wherein nitrogen is continuously directed out of the first channel by one or more features such that nitrogen accumulation is reduced within the first channel, thereby increasing the hydrogen consumption rate compared to a comparable fuel cell lacking any features.

[0444] EMBODIMENT 96 96. The system of any one of embodiments 87-95, wherein the hydrogen consumption rate of the fuel cell when the first continuous stream is contacted with the anode is at least about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0445] EMBODIMENT 97 97. The system of any one of embodiments 87-96, wherein the hydrogen consumption rate of the fuel cell when the first continuous stream is contacted with the anode is at most about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 99% of the hydrogen in the first continuous stream.

[0446] EMBODIMENT 98 98. The system of any one of embodiments 87-97, wherein the instructions executable by the controller are further configured to intermittently reduce the hydrogen consumption rate to purge at least one of hydrogen, nitrogen, or water.

[0447] EMBODIMENT 99 99. The system of any one of embodiments 87-98, wherein the instructions executable by the controller are further configured to: reduce a hydrogen consumption rate and direct at least a portion of the first continuous stream to an ammonia reformer.

[0448] EMBODIMENT 100 99. The system of any one of embodiments 87-99, wherein the instructions executable by the controller are further configured to reduce a hydrogen consumption rate of the fuel cell to zero and direct at least a portion of the first continuous stream to an ammonia reformer.

[0449] EMBODIMENT 101 101. The system of embodiment 99 or 100, wherein the instructions executable by the controller are further configured to combust at least a portion of the first continuous stream directed to the ammonia reformer in one or more combustion exhausts of the one or more fired heaters, the one or more fired heaters being in communication with the ammonia reformer to heat the ammonia reformer, the one or more fired heaters being in fluid communication with a fuel to receive at least a portion of the first continuous stream.

[0450] EMBODIMENT 102 1. A fuel cell comprising: an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof; and a second channel comprising a second inlet and a second outlet, the second channel in fluid communication with the cathode; and wherein the fuel cell has a ratio of power output of the fuel cell to projected surface area of ​​the anode of at least about 0.05 W / cm. 2 and a second channel configured to provide a first continuous flow comprising about 25 mole percent nitrogen and about 75 mole percent hydrogen to the first inlet and a second continuous flow comprising at least 20 mole percent oxygen to the second inlet.

[0451] EMBODIMENT 103 Ratios of at least about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm 2 103. The fuel cell of embodiment 102, wherein

[0452] EMBODIMENT 104 Ratios up to about 0.1, 0.15, 0.2, 0.25, 0.3, 0.35, or 0.4 W / cm 2 104. The fuel cell of embodiment 102 or 103, wherein

[0453] EMBODIMENT 105 105. The fuel cell of any one of embodiments 102-104, wherein the ratio is based on a first continuous flow comprising a hydrogen flow rate of at least about 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000 moles / second.

[0454] EMBODIMENT 106 106. The fuel cell of any one of embodiments 102-105, wherein the ratio is based on a second continuous flow comprising an oxygen flow rate of at least about 0.0001, 0.001, 0.01, 0.1, 1, 10, 100, 1000, 10000, 100000, 1000000 moles / second.

[0455] EMBODIMENT 107 107. The fuel cell of any one of embodiments 102-106, wherein the ratio is based on a second continuous flow comprising air.

[0456] EMBODIMENT 108 108. The fuel cell of any one of embodiments 102-107, wherein the ratio is based on a first continuous stream comprising hydrogen and nitrogen from an ammonia reformer.

[0457] EMBODIMENT 109 109. The fuel cell of any one of embodiments 102-108, wherein the projected surface area of ​​the anode comprises the maximum possible surface area of ​​the anode projected onto a plane.

[0458] Embodiment 110 110. The fuel cell of any one of embodiments 102-109, wherein the projected surface area of ​​the anode comprises the surface area of ​​the largest surface of the anode.

[0459] EMBODIMENT 111 1. A fuel cell comprising: an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features; and a second channel comprising a second inlet and a second outlet, the second channel in fluid communication with the cathode; the fuel cell in fluid communication with an ammonia reformer configured to supply nitrogen and hydrogen to the fuel cell; the fuel cell configured to generate power that is at least 80% of a reference power, the reference power being generated using the fuel cell receiving into the first inlet a continuous flow comprising at least 99 mole % hydrogen, and the power being generated at the same current or at the same hydrogen consumption rate as the reference power.

[0460] EMBODIMENT 112 112. The fuel cell of embodiment 111, wherein the power is at least 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0461] EMBODIMENT 113 113. The fuel cell of embodiment 111 or 112, wherein the power is up to 60, 70, 80, 90, 91, 92, 93, 94, 95, 96, 97, 98, or 99% of the reference power.

[0462] EMBODIMENT 114 1. A system, comprising: an ammonia reformer; and a fuel cell in fluid communication with the ammonia reformer, the fuel cell comprising an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; and a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof, the one or more features comprising a depth of less than 10 mm. and a second channel having a second inlet and a second outlet, the second channel in fluid communication with the cathode; and a controller comprising at least one processor configured to execute executable instructions, the instructions executable by the controller configured to: direct ammonia to an ammonia reformer to produce a first continuous stream comprising hydrogen and nitrogen; direct a second continuous stream comprising oxygen to the cathode of the fuel cell; and direct the first continuous stream to an anode of the fuel cell to react the hydrogen and oxygen to generate electricity.

[0463] EMBODIMENT 115 The system of embodiment 114, wherein the one or more features have a depth of less than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0464] EMBODIMENT 116 The system of embodiment 114 or 115, wherein the one or more features have a depth of greater than 5, 4, 3, 2, 1, 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06, 0.05, 0.04, 0.03, 0.02, or 0.01 mm.

[0465] EMBODIMENT 117 The system of any one of embodiments 114 to 116, wherein the depth is at least 1 / 32, 1 / 16, 1 / 8, 1 / 4, or 1 / 2 the thickness of the first channel.

[0466] EMBODIMENT 118 The system of any one of embodiments 114 to 117, wherein the depth is at most 1 / 32, 1 / 16, 1 / 8, 1 / 4, or 1 / 2 of the thickness of the first channel.

[0467] EMBODIMENT 119 The system of any one of embodiments 114 to 118, wherein the ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel is at least 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0468] Embodiment 120 A system described in any one of embodiments 114 to 119, wherein the ratio of the first projected surface area of ​​the one or more features to the second projected surface area of ​​the first channel is at most 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, or 0.9.

[0469] EMBODIMENT 121 121. The system of any one of embodiments 114-120, wherein the ammonia reformer produces a first continuous stream further comprising up to 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm ammonia.

[0470] EMBODIMENT 122 122. The system of any one of embodiments 114-121, wherein the ammonia reformer produces a first continuous stream further comprising at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm of ammonia.

[0471] EMBODIMENT 123 123. The system or fuel cell of any one of embodiments 87-122, wherein the one or more features comprises two or more features.

[0472] EMBODIMENT 124 124. The system or fuel cell of embodiment 123, wherein at least a first segment of a first feature of the two or more features is substantially parallel to a second segment of a second feature of the two or more features.

[0473] EMBODIMENT 125 124. The system or fuel cell of embodiment 123, wherein at least a first segment of a first feature of the two or more features is substantially perpendicular to a second segment of a second feature of the two or more features.

[0474] EMBODIMENT 126 124. The system or fuel cell of embodiment 123, wherein at least a first segment of a first feature of the two or more features is at an angle to a second segment of a second feature of the two or more features, the angle being between 0 and 90 degrees, between 15 and 75 degrees, between 0 and 30 degrees, or between 30 and 60 degrees.

[0475] EMBODIMENT 127 127. A system or fuel cell according to any one of embodiments 123 to 126, wherein two or more features are linked together.

[0476] EMBODIMENT 128 127. A system or fuel cell according to any one of embodiments 123 to 126, wherein two or more features are separated.

[0477] EMBODIMENT 129 A system or fuel cell according to any one of embodiments 123 to 126, wherein two or more features intersect.

[0478] Embodiment 130 130. The system or fuel cell of any one of embodiments 87 to 129, wherein the one or more features are completely surrounded by the first channel.

[0479] EMBODIMENT 131 130. The system or fuel cell of any one of embodiments 87-129, wherein the one or more features are partially surrounded by the first channel.

[0480] EMBODIMENT 132 A system or fuel cell described in any one of embodiments 87 to 131, wherein the one or more features include a serpentine shape.

[0481] EMBODIMENT 133 133. The system or fuel cell of any one of embodiments 87-132, wherein the one or more features are substantially parallel to the longest side of the first channel.

[0482] EMBODIMENT 134 133. The system or fuel cell of any one of embodiments 87-132, wherein the one or more features are substantially parallel to the shortest side of the first channel.

[0483] EMBODIMENT 135 135. The system or fuel cell of any one of embodiments 87-134, wherein the fuel cell comprises a plurality of channels in fluid communication with the anode, the plurality of channels comprising the first channel.

[0484] EMBODIMENT 136 136. A system or fuel cell as described in embodiment 135, wherein the multiple channels comprise a stack of layers adjacent to one another.

[0485] EMBODIMENT 137 A system or fuel cell as described in embodiment 135 or 136, wherein at least one of the plurality of channels does not have any features comprising (i) one or more cut portions, (ii) one or more cutout portions, (iii) one or more groove portions, or (iv) any combination thereof, or is completely absent.

[0486] EMBODIMENT 138 The system or fuel cell of any one of embodiments 87 to 137, wherein one or more features are further configured to facilitate purging a selected material from the anode gas diffusion layer, the selected material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0487] EMBODIMENT 139 139. The system or fuel cell of embodiment 138, wherein the fuel cell further comprises one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0488] EMBODIMENT 140 The system or fuel cell of any one of embodiments 87 to 139, wherein the first channel comprises a felt, foam, cloth, or paper material.

[0489] EMBODIMENT 141 141. The system or fuel cell of embodiment 140, wherein the felt, foam, cloth, or paper material is a carbon-based material.

[0490] EMBODIMENT 142 142. The system or fuel cell of any one of embodiments 87-141, wherein the one or more features extend across at least a portion of a surface of the first channel.

[0491] EMBODIMENT 143 143. The system or fuel cell of any one of embodiments 87-142, wherein the electrolyte comprises a proton exchange membrane.

[0492] EMBODIMENT 144 A system or fuel cell according to any one of embodiments 87 to 143, wherein the fuel cell is configured to allow nitrogen to be purged from the fuel cell while the fuel cell is generating electricity.

[0493] EMBODIMENT 145 145. The system or fuel cell of any one of embodiments 87 to 144, wherein the first channel is supplied with a stream comprising ammonia at a concentration of at most 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0494] EMBODIMENT 146 146. The system or fuel cell of any one of embodiments 87-145, wherein the first channel is supplied with a stream comprising ammonia at a concentration of at least 1000, 900, 800, 700, 600, 500, 400, 300, 200, 100, 90, 80, 70, 60, 50, 40, 30, 20, 10, 9, 8, 7, 6, 5, 4, 3, 2, or 1 ppm.

[0495] EMBODIMENT 147 147. The system or fuel cell of any one of embodiments 87-146, wherein the one or more features increase the power density of the fuel cell by at least 5, 10, 20, 40, 60, 80, 100, 120, 140, 160, 180, or 200%.

[0496] EMBODIMENT 148 The system or fuel cell of any one of embodiments 87-147, wherein the power density of the fuel cell is at least about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0497] EMBODIMENT 149 The system or fuel cell of any one of embodiments 87-148, wherein the power density of the fuel cell is at most about 0.1, 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, or 30 kW / L.

[0498] Embodiment 150 150. The system or fuel cell of embodiment 149, further comprising one or more fired heaters for combusting an outlet stream output by the fuel cell to heat the ammonia reformer, the outlet stream comprising unconverted hydrogen.

[0499] EMBODIMENT 151 The system or fuel cell of embodiment 150, further comprising one or more supply units for supplying at least oxygen to the one or more fired heaters.

[0500] EMBODIMENT 152 151. The system or fuel cell of embodiment 149 or 150, further comprising one or more dehydration devices for removing water in the outlet stream prior to combusting the unconverted hydrogen.

[0501] EMBODIMENT 153 151. The system or fuel cell of embodiment 150, wherein the system is configured to combust unconverted hydrogen in the combustion exhaust of the one or more fired heaters.

[0502] EMBODIMENT 154 A system or fuel cell described in any one of embodiments 87 to 153, further comprising one or more flow regulators, pressure regulators, control units, or any combination thereof, for adjusting the absolute pressure of the input or exhaust flow of the fuel cell.

[0503] EMBODIMENT 155 A system or fuel cell as described in embodiment 154, wherein one or more flow regulators, pressure regulators, control units, or any combination thereof are positioned upstream or downstream of the fuel cell.

[0504] EMBODIMENT 156 A system or fuel cell as described in embodiment 154 or 155, wherein one or more flow regulators, pressure regulators, control units, or any combination thereof are disposed downstream of the fuel cell to reduce or prevent backflow of unconverted hydrogen.

[0505] EMBODIMENT 157 The system or fuel cell according to any one of embodiments 87 to 156, further comprising an electrical load connected to the electrochemical circuit.

[0506] EMBODIMENT 158 158. The system or fuel cell of embodiment 157, wherein the electrical load comprises one or more electrical devices.

[0507] EMBODIMENT 159 A system or fuel cell as described in embodiment 158, wherein the electrical load includes one or more power grids.

[0508] EMBODIMENT 160 A system or fuel cell as described in embodiment 158, wherein the electrical load includes an engine or motor.

[0509] EMBODIMENT 161 161. The system or fuel cell of any one of embodiments 87 to 160, wherein the fuel cell comprises a plurality of fuel cells in communication with an ammonia reformer, the ammonia reformer configured to supply a plurality of streams comprising hydrogen and nitrogen to the plurality of fuel cells.

[0510] EMBODIMENT 162 162. The system or fuel cell of embodiment 161, wherein the system is configured to direct unconverted hydrogen from the multiple fuel cells to one or more combustors in thermal communication with the ammonia reformer.

[0511] EMBODIMENT 163 163. A system or fuel cell as described in embodiment 161 or 162, wherein at least one fuel cell of the plurality of fuel cells has a different power output than other fuel cells of the plurality of fuel cells.

[0512] EMBODIMENT 164 A system or fuel cell according to any one of embodiments 161 to 163, wherein at least one fuel cell of the plurality of fuel cells is configured to reduce its power output.

[0513] EMBODIMENT 165 A system or fuel cell as described in any one of embodiments 161 to 164, wherein one or more ammonia reformers in fluid communication with the plurality of fuel cells supply a stream to at least one of the plurality of fuel cells having a flow rate that is different from the flow rates of other streams supplied to the other fuel cells.

[0514] EMBODIMENT 166 A system or fuel cell as described in any one of embodiments 161 to 164, wherein one or more ammonia reformers in fluid communication with the plurality of fuel cells are configured to supply a plurality of streams to the plurality of fuel cells, and the flow rates of the plurality of streams are approximately the same as other flow rates of other streams of the plurality of streams or are within a selected tolerance range of the other flow rates of the other streams.

[0515] EMBODIMENT 167 167. The system or fuel cell of embodiment 166, wherein the selected tolerance range is about 10, 20, 30, 40, 50, 60, 70, 80, 90, or 100%.

[0516] EMBODIMENT 168 A system or fuel cell described in any one of embodiments 161 to 167, wherein the plurality of fuel cells includes at least one fuel cell that differs from the other fuel cells in size, output power, hydrogen consumption rate, power density, or operating temperature.

[0517] EMBODIMENT 169 1. A fuel cell comprising: an anode; a cathode; and a membrane between the anode and the cathode, wherein the anode comprises an anode gas diffusion layer comprising one or more channels for directing a feed material comprising hydrogen and nitrogen to the anode for processing the feed material to generate an electric current, the one or more channels comprising one or more features comprising (i) one or more cuts, (ii) one or more cutouts, or (iii) one or more grooves configured to enhance diffusion and transport of the feed material through the anode gas diffusion layer, the one or more features being configured to direct a flow of nitrogen from the anode gas diffusion layer out of the fuel cell such that nitrogen does not accumulate in the anode gas diffusion layer.

[0518] Embodiment 170 170. The fuel cell of embodiment 169, wherein the one or more features comprise two or more features.

[0519] EMBODIMENT 171 A fuel cell as described in embodiment 169 or 170, wherein the one or more features are further configured to facilitate purging a selected material from the anode gas diffusion layer, the selected material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

[0520] EMBODIMENT 172 172. The fuel cell of embodiment 171, further comprising one or more outlet ports for exhausting the selected material and unconverted hydrogen from the fuel cell.

[0521] EMBODIMENT 173 A fuel cell according to any one of embodiments 169 to 172, wherein the processing of the raw material includes dissociating one or more hydrogen molecules of the raw material into one or more protons and one or more electrons.

[0522] EMBODIMENT 174 174. The fuel cell of any one of embodiments 169 to 173, wherein the anode gas diffusion layer may comprise a felt, foam, cloth, or paper material.

[0523] EMBODIMENT 175 175. The fuel cell of embodiment 174, wherein the felt, foam, cloth, or paper material is a carbon-based material.

[0524] EMBODIMENT 176 176. A fuel cell according to any one of embodiments 169 to 175, wherein the one or more features extend across at least a portion of a surface of the one or more channels.

[0525] EMBODIMENT 177 177. The fuel cell of any one of embodiments 170-176, wherein the two or more features are parallel to one another.

[0526] EMBODIMENT 178 178. The fuel cell of any one of embodiments 170-177, wherein two or more features are perpendicular to each other.

[0527] EMBODIMENT 179 179. The fuel cell of any one of embodiments 170-178, wherein the two or more features are disposed at an angle relative to one another, the angle ranging from 0 degrees to 90 degrees.

[0528] Embodiment 180 180. The fuel cell of any one of embodiments 170-179, wherein two or more features intersect each other.

[0529] Embodiment 181 181. The fuel cell of any one of embodiments 170-180, wherein two or more features do not intersect.

[0530] EMBODIMENT 182 182. The fuel cell of any one of embodiments 169-181, wherein the anode gas diffusion layer comprises multiple layers.

[0531] EMBODIMENT 183 183. The fuel cell of any one of embodiments 169-182, wherein at least one layer of the plurality of layers comprises one or more channels comprising one or more features.

[0532] EMBODIMENT 184 184. The fuel cell of embodiment 183, wherein the plurality of layers comprises a first layer having a first set of features and a second layer having a second set of features.

[0533] EMBODIMENT 185 185. The fuel cell of embodiment 184, wherein the first set of features and the second set of features comprise the same or similar sets of features.

[0534] EMBODIMENT 186 186. The fuel cell of embodiment 184 or 185, wherein the first set of features and the second set of features comprise different sets of features having different shapes, sizes, arrangements, or orientations.

[0535] EMBODIMENT 187 187. The fuel cell of any one of embodiments 184-186, wherein the first set of features and the second set of features overlap or partially overlap.

[0536] Embodiment 188 187. The fuel cell of any one of embodiments 184-186, wherein the first set of features and the second set of features do not overlap.

[0537] EMBODIMENT 189 189. The fuel cell of any one of embodiments 169-188, wherein at least one feature of the one or more features has a depth in the range of about 0.01 millimeters (mm) to about 10 mm.

[0538] Embodiment 190 A fuel cell system comprising a plurality of fuel cells comprising the fuel cell of any one of embodiments 169 to 189, and at least one ammonia reformer or reactor in fluid communication with the plurality of fuel cells, wherein the at least one ammonia reformer or reactor is configured to (i) produce a feedstock material and (ii) supply the feedstock material to the fuel cell.

[0539] EMBODIMENT 191 191. The fuel cell system of embodiment 190, wherein the multiple fuel cells are arranged (i) adjacent to each other in a horizontal configuration, or (ii) on top of each other in a stacked configuration.

[0540] EMBODIMENT 192 192. The fuel cell system of embodiment 190 or 191, wherein the plurality of fuel cells comprises at least one proton exchange membrane fuel cell (PEMFC).

[0541] EMBODIMENT 193 A fuel cell system comprising a fuel cell according to any one of embodiments 169 to 192, wherein the fuel cell system comprises a controller configured to operate the fuel cell and enable the fuel cell to purge nitrogen from the fuel cell while the fuel cell is generating electricity.

[0542] EMBODIMENT 194 194. The fuel cell system of any one of embodiments 190 to 193, comprising a controller configured to operate the fuel cell and enable purging of nitrogen from the fuel cell while the fuel cell is generating electricity.

[0543] EMBODIMENT 195 195. The fuel cell system of any one of embodiments 190-194, wherein at least one of the one or more features has a depth in the range of about 0.01 millimeters (mm) to about 10 mm.

[0544] EMBODIMENT 196 196. The fuel cell system of any one of embodiments 190-195, wherein the fuel cell system further comprises one or more inlet ports configured to receive a feedstock material, wherein the ammonia concentration in the feedstock material is less than 1 ppm.

[0545] EMBODIMENT 197 197. The fuel cell system of any one of embodiments 190-196, wherein the fuel cell system further comprises one or more outlet ports configured to direct unconverted hydrogen from the plurality of fuel cells to at least one ammonia reformer or reactor, wherein the unconverted hydrogen is combusted to heat the ammonia reformer or reactor.

[0546] Although the present specification shows and describes preferred embodiments of the present invention, it will be apparent to those skilled in the art that such embodiments are provided by way of example only. The present invention is not intended to be limited by the specific examples provided herein. Although the present invention has been described with reference to the foregoing specification, the description and illustration of the embodiments herein are not intended to be construed in a limiting sense. Numerous variations, changes, and substitutions will occur to those skilled in the art without departing from the present invention. Furthermore, it should be understood that all aspects of the present invention are not limited to the specific descriptions, configurations, or relative proportions set forth herein, which depend upon a variety of conditions and variables. It is understood that various alternatives to the embodiments of the present invention described herein can be used in carrying out the present invention. It is therefore intended that the present invention cover any such alternatives, modifications, variations, or equivalents. The following claims define the scope of the present invention, and it is intended that methods and structures within the scope of these claims and their equivalents are covered thereby.

Claims

1. 1. A method for generating electricity using a fuel cell, comprising: (a) reacting ammonia using an ammonia reformer to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer being in fluid communication with the fuel cell, the ammonia reformer comprising one or more fired heaters, the fuel cell comprising: i. an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; ii. a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features configured to (i) increase the hydrogen consumption rate of the fuel cell by at least 20% or (ii) increase the output voltage of the fuel cell by at least 10% at the same hydrogen consumption rate when the first continuous flow contacts the anode, compared to a comparable fuel cell lacking any features, the one or more features comprising: (1) one or more cuts, (2) one or more cutouts, (3) one or more grooves, or (4) any combination thereof; a second channel having a second inlet and a second outlet, the second channel being in fluid communication with the cathode; (b) directing the first continuous flow through the first inlet into the first channel so that the hydrogen contacts the anode; (c) directing a second continuous flow of oxygen into the second channel via the second inlet such that the oxygen contacts the cathode; (d) reacting the hydrogen and the oxygen to generate electricity using the fuel cell; (e) reducing the hydrogen consumption rate of the fuel cell and discharging a third continuous stream from the fuel cell comprising unconverted hydrogen; (f) directing the third continuous stream containing unconverted hydrogen to the ammonia reformer; (g) combusting at least a portion of the third continuous stream to heat the ammonia reformer; (h) exhausting at least a portion of the third continuous stream at one or more combustion exhausts of the one or more fired heaters, the one or more fired heaters being in thermal communication with the ammonia reformer for heating the ammonia reformer, and the one or more fired heaters being in fluid communication with the fuel cell for receiving the at least a portion of the third continuous stream; A method comprising:

2. 2. The method of claim 1, wherein nitrogen is continuously purged from the first channel by the one or more features such that nitrogen accumulation is reduced within the first channel, thereby increasing the hydrogen consumption rate compared to an equivalent fuel cell lacking any of the features.

3. 10. The method of claim 1, wherein the hydrogen consumption rate of the fuel cell is at least about 20% of the hydrogen in the first continuous stream when the first continuous stream contacts the anode.

4. 4. The method of claim 1, further comprising intermittently reducing the hydrogen consumption rate to purge at least one of hydrogen, nitrogen, or water.

5. The fuel cell, wherein the ratio of the power output of the fuel cell to the projected surface area of ​​the anode is at least about 0.05 W / cm ２ The method according to any one of claims 1 to 3, configured to obtain

6. 1. A system comprising: (a) an ammonia reformer configured to react ammonia to produce a first continuous stream comprising nitrogen and hydrogen, the ammonia reformer comprising one or more fired heaters; (b) a fuel cell in fluid communication with the ammonia reformer, the fuel cell comprising: i. an electrochemical circuit comprising an anode, a cathode, and an electrolyte between the anode and the cathode; ii. a first channel comprising a first inlet and a first outlet, the first channel in fluid communication with the anode, the first channel comprising one or more features configured to (i) increase the hydrogen consumption rate by at least 20% or (ii) increase the output voltage at the same hydrogen consumption rate by at least 10% when the first continuous flow contacts the anode compared to a comparable fuel cell lacking any features, the one or more features comprising: (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof; iii. a fuel cell comprising: a second channel comprising a second inlet and a second outlet, said second channel in fluid communication with said cathode; (c) a controller comprising at least one processor configured to execute executable instructions that, when executed, direct the controller to direct the system; i. reacting the ammonia using the ammonia reformer to produce the first continuous stream comprising hydrogen and nitrogen; ii. directing a second continuous stream comprising oxygen to the cathode of the fuel cell; iii. directing the first continuous stream to the anode of the fuel cell to react the hydrogen with oxygen to generate electricity; iv. reducing the hydrogen consumption rate of the fuel cell and discharging a third continuous stream from the fuel cell comprising unconverted hydrogen; v. directing the third continuous stream containing unconverted hydrogen to the ammonia reformer; vi. combusting at least a portion of the third continuous stream to heat the ammonia reformer; vii. a controller that discharges at least a portion of the third continuous stream at one or more combustion exhausts of the one or more fired heaters, wherein the one or more fired heaters are in thermal communication with the ammonia reformer to heat the ammonia reformer, and the one or more fired heaters are in fluid communication with the fuel cell to receive the at least a portion of the third continuous stream; A system comprising:

7. 7. The system of claim 6, wherein the hydrogen consumption rate of the fuel cell is at least about 20% of the hydrogen in the first continuous stream when the first continuous stream contacts the anode.

8. The system of claim 6 , wherein the fuel cell comprises a plurality of channels in fluid communication with the anode, the plurality of channels comprising the first channel.

9. The system of claim 8 , wherein the plurality of channels comprises a stack of adjacent layers.

10. 10. The system of claim 9, wherein at least one channel of the plurality of channels does not include any of the features comprising (i) one or more cuts, (ii) one or more cutouts, (iii) one or more grooves, or (iv) any combination thereof.

11. 11. The system of claim 6, wherein the one or more features are further configured to facilitate purging a selected material from the anode gas diffusion layer of the first channel, the selected material comprising one or more of nitrogen, ammonia, water, or one or more impurities.

12. The system of any one of claims 6 to 10, wherein the one or more features are configured to purge nitrogen from the fuel cell while the fuel cell is generating electricity.

13. 11. The system according to any one of claims 6 to 10, wherein the concentration of ammonia in the first continuous stream is at most 1000 ppm.

14. The system of any one of claims 6 to 10, wherein the one or more features increase the power density of the fuel cell by at least 10%.

15. The fuel cell, wherein the ratio of the power output of the fuel cell to the projected surface area of ​​the anode is at least about 0.05 W / cm ２ The system according to any one of claims 6 to 10, configured to obtain:

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