Water separator in a fuel cell stack

Abstract

An embodiment of a method for separating water within a fuel cell system integrated into a fuel cell stack is disclosed herein. A plurality of fuel cell assemblies are compressed together to form a fuel cell stack. By aligning the cathode outlets of the fuel cell assemblies, a collection cavity fluidly connected to each fuel cell assembly is formed within the fuel cell stack. A water outlet is connected to a collection cavity having an internally inclined water collection ramp. The integrated water separator reduces the size of the fuel cell system.

Description

Technology Field

[0001] Related applications

[0002] This application is a PCT application claiming priority to UK patent application No. 2319828.6 filed on December 21, 2023, and the disclosure of said UK patent application is incorporated herein as if its entire contents were fully described herein by reference.

[0003] Technology field

[0004] The present disclosure generally relates to a device and method for collecting and separating water from the cathode exhaust port of a fuel cell stack. Background Technology

[0005] A typical fuel cell system includes a fuel cell stack for generating electricity, a hydrogen feed as fuel for the fuel cell stack, an oxygen (air) supply system for supplying oxygen-containing air as an oxidant for an electrochemical reaction, and a thermal management unit for removing reaction heat from the fuel cell stack and managing the removal of humidity and water within the fuel cell stack. The fuel cell system generates electricity as well as heat and water.

[0006] In a fuel cell assembly, each unit has an anode, a cathode, and an electrolyte (electrolyte membrane). Hydrogen is supplied to the anode and oxygen-containing air is supplied to the cathode. Through the membrane electrode assembly (MEA), hydrogen and oxygen generate electricity, heat, and water.

[0007] A stack is formed from a plurality of the aforementioned fuel cells arranged with separate anode fluid flow paths and cathode fluid flow paths. Such a stack is typically in the form of a block comprising a plurality of individual fuel cell plates held together by end plates at both ends of the stack. For efficient operation, it is important that the polymer ion transfer membrane be kept hydrated. Additionally, it is important that the temperature of the stack be controlled. Therefore, a coolant may be supplied to the stack for cooling and / or hydration.

[0008] An important consideration in the operation of such fuel cells is the management of water within the MEA. During the operation of a PEM fuel cell, water, a product of the reaction between hydrogen and oxygen, forms in the catalytic sites of the MEA. Depending on the temperature and pressure at the time of generation, this water exists in one or more phases, including liquid, vapor, and transition phases, and must be discharged from the MEA through the cathode diffusion structure while oxygen is transported to the cathode surface of the MEA. However, it is also important that the MEA be kept in an appropriately hydrated state to ensure that the internal electrical resistance of the fuel cell is maintained within acceptable limits. Failure to control MEA humidification leads to hot spots and potential cell failure and / or poor electrical cell performance. The anode fluid flow field plate and the cathode fluid flow field plate may each comprise a rigid electrically conductive material having fluid flow channels on the surface adjacent to the diffusion structure for the transport of reactant gases (e.g., hydrogen and oxygen) and the removal of exhaust gases (e.g., unused oxygen and water vapor).

[0009] A fuel cell stack comprises a series of individual fuel cells formed layer by layer in a stack array. Each fuel cell itself may include various layered components, such as a polymer electrolyte membrane, a gas diffusion layer, a fluid flow plate, and various sealing gaskets to provide fluid fuel and oxidant distribution on the active surface of the membrane while maintaining fluid tightness. Fluid input and fluid output are guided through the flow field and flow plate at the fuel cell level and through a connected manifold at the stack level.

[0010] The present disclosure teaches an embodiment of a fuel cell stack with a smaller footprint that utilizes evaporative cooling. Vehicle engine compartments tend to be spatially constrained to minimize the size of the engine or power supply compartment. Conventional fuel cell stacks separate water generated during operation at a water separator device outside the fuel cell stack and at a water separator device as part of the rest of the plant.

[0011] The aforementioned requirements are satisfied by various embodiments and methods of use of an integrated water separator for a fuel cell system disclosed throughout this application. According to some embodiments of the present disclosure, a method for separating water in a manifold or duct of a fuel cell stack is provided, which is formed by a fuel cell assembly frame aligned in the stack with a common opening fluidly communicating with an input or output portion of fuel, air, or water.

[0012] According to some aspects of the present disclosure, a system and method for collecting water and separating vapor from a liquid within a fuel cell system are disclosed. An aspect of the disclosed integrated water separator comprises a plurality of fuel cell assemblies configured to be compressed together to form a stack having an upper and a lower portion. Each fuel cell assembly comprises one or more frames configured to support a membrane electrode assembly (MEA), at least one hydrogen outlet configured to collect hydrogen from the anode side of the MEA, and at least one cathode outlet configured to collect at least air and water from the cathode side of the MEA, wherein the cathode outlet of the fuel cell assembly is configured to form a collection cavity within the fuel cell stack that is fluidly connected to each fuel cell assembly. The water outlet is fluidly connected to the collection cavity, and a water collection means, such as a ramp, is configured to be fitted into the collection cavity.

[0013] In some cases, the cathode flow field is configured to distribute oxygen across the MEA from at least one air inlet formed within the frame. In some cases, the anode flow field is configured to distribute hydrogen across the MEA from one or more inlets formed in the frame. In some cases, at least one gas diffusion layer is adjacent to at least one of the cathode flow field and the anode flow field. In some cases, one or more inlets formed in each frame may be configured to supply hydrogen gas to the anode side of the MEA. In some cases, one or more inlets formed in each frame may be configured to supply air gas to the cathode side of the MEA. In some cases, one or more inlets formed in each frame may be configured to supply water to at least the cathode side of the MEA. In some cases of the fuel cell system of claim 1, the cathode exhaust port is divided, and the lamp is divided so as to be fitted inside the cathode exhaust port.

[0014] According to some aspects of the present disclosure, a system and method for collecting water and separating vapor from a liquid within a fuel cell system are disclosed. An aspect of the disclosed integrated water separator comprises a plurality of fuel cell assemblies configured to be compressed together to form a stack having an upper and a lower portion. Each fuel cell assembly comprises one or more frames configured to support a membrane electrode assembly (MEA), at least one hydrogen outlet configured to collect hydrogen from the anode side of the MEA, and at least one cathode outlet configured to collect at least air and water from the cathode side of the MEA, wherein the cathode outlet of the fuel cell assembly is configured to form a collection cavity within the fuel cell stack that is fluidly connected to each fuel cell assembly. A water outlet is fluidly connected to the collection cavity, and a water collection means, such as a lamp, is configured to be fitted into the collection cavity. The water collection lamp comprises a first surface, a second surface, a first edge, a second edge, an upper portion, and a lower portion, and is configured to be fitted into the collection cavity to collect water from the cathode outlet. In some cases, a gutter extends from at least one side of the ramp.

[0015] In some cases, a spine is attached longitudinally to at least a portion of the first edge, and a tooth is formed on at least a portion of the second edge. A gutter is attached to the spine at one end, and water collected on the ramp falls from the gutter onto the toothed edge. In some cases, multiple spines or partial spines are formed on the ramp. In some cases, the toothed portion is a wavy edge or a flat edge.

[0016] In some cases, at least one of the ramp and gutter has at least one of a texture, bump, protrusion, divot, channel, and groove.

[0017] In some cases, the air manifold is in fluid communication with the collection cavity. In some cases, the upper collector is formed as part of the interior of the exhaust manifold or is attached to the interior of the exhaust manifold, having a fin facing the collection cavity, and water collected on the fin during operation is guided to a water collection lamp.

[0018] In some cases, at least one outer surface of the upper collector and the lamp has a predetermined surface lubricity or surface roughness. In some cases, at least one outer surface of the upper collector and the lamp is either hydrophobic or hydrophilic.

[0019] According to some aspects of the present disclosure, a system and method for collecting water and separating vapor from a liquid within a fuel cell system are disclosed. An aspect of the disclosed integrated water separator comprises a plurality of fuel cell assemblies configured to be compressed together to form a stack having an upper and a lower portion. Each fuel cell assembly comprises one or more frames configured to support a membrane electrode assembly (MEA), at least one hydrogen outlet configured to collect hydrogen from the anode side of the MEA, and at least one cathode outlet configured to collect at least air and water from the cathode side of the MEA, wherein the cathode outlet of the fuel cell assembly is configured to form a collection cavity within the fuel cell stack that is fluidly connected to each fuel cell assembly. A water outlet is fluidly connected to the collection cavity, and a water collection means, such as a lamp, is configured to be fitted into the collection cavity. The water collection lamp comprises a first surface, a second surface, a first edge, a second edge, an upper portion, and a lower portion, and is configured to be fitted into the collection cavity to collect water from the cathode outlet. A water collection ramp is attached within the collection cavity at a certain angle to the floor of the collection cavity. In some cases, a gutter extends from at least one side of the ramp.

[0020] In some cases, the cathode flow field is configured to distribute oxygen across the MEA from at least one air inlet formed in each frame. In some cases, the anode flow field is configured to distribute hydrogen across the MEA from one or more inlets formed in the frame. In some cases, at least one gas diffusion layer is adjacent to at least one of the cathode flow field and the anode flow field.

[0021] When the above fuel cell system is in operation, one or more inlets formed in each frame may be configured to supply hydrogen gas to the anode side of the MEA, and one or more inlets formed in each frame may be configured to supply air gas to the cathode side of the MEA. An additional one or more inlets formed in each frame may be configured to supply water to at least the cathode side of the MEA, and a water collection means further comprises a body portion having an outer surface configured to be fitted into a collection cavity and is configured to collect water from a cathode exhaust port.

[0022] According to some aspects of the present disclosure, a system and method for regulating water collected within a fuel cell system and separating vapor from a liquid are disclosed, wherein the system and method comprise a plurality of fuel cell assemblies configured to be compressed together to form a stack having an upper and a lower portion. Each fuel cell assembly comprises one or more frames configured to support a membrane electrode assembly (MEA), at least one hydrogen outlet configured to collect hydrogen from the anode side of the MEA, and at least one cathode outlet configured to collect at least air and water from the cathode side of the MEA, wherein the cathode outlet of the fuel cell assembly comprises at least one cathode outlet configured to form a collection cavity fluidly connected to each fuel cell assembly within the fuel cell stack. A water outlet fluidly communicates with the collection cavity, and the water collection means is configured to have a lamp that fits into the collection cavity. In some cases, the lamp comprises one or more of a pin, a bump, a protrusion, a divot, a channel, and a groove. In some cases, the lamp is made of a plurality of portions. In some cases, the lamp has at least one of a predetermined surface lubricity and surface roughness. In some cases, the lamp is either hydrophobic or hydrophilic. In some cases, at least one region of the lamp is more hydrophilic or more hydrophobic than another part of the outer surface. In some cases, the lamp has both hydrophilic and hydrophobic regions. In some cases, the lamp has at least some textured regions, and in other cases, the lamp is not textured.

[0023] In some cases, an exhaust head is added and fluidly communicates with the collection cavity. In some cases, a fan is added that fluidly communicates with the collection cavity and is located within the water collection means. Brief explanation of the drawing

[0024] This application will be better understood when read in conjunction with the accompanying drawings. For the purpose of presenting the subject matter, exemplary aspects of the subject matter are depicted in the drawings, but the subject matter to be disclosed herein is not limited to the specific methods, devices, and systems disclosed. Figure 1 is a flowchart of the operation mode of an internal water separator within a fuel cell stack. Figure 2 is a stack of a fuel cell assembly. FIG. 3a is a plan view of some embodiment of a fuel cell assembly. FIG. 3b is a plan view of some embodiment of an alternative example of a fuel cell assembly. FIG. 4a is an exploded view of an assembly of a fuel cell system having an internal water separator. FIG. 4b is an exploded view of an alternative example of an assembly of a fuel cell system having an internal water separator. FIG. 5a is an assembly diagram of a fuel cell system having an internal water separator. FIG. 5b is a partial assembly diagram of a fuel cell system having an internal water separator, illustrating a plurality of water outlets. FIG. 6a is a cross-sectional view of a fuel cell system after assembly, illustrating an embodiment of an integrated water separator. FIG. 6b is a front view of an embodiment of a water collection ramp of a fuel cell system having an internal water separator of FIG. 4. Fig. 6c is a cross-sectional view of the water collection ramp of Fig. 6b along line AA. FIG. 6d is a bottom view of an embodiment of an additional upper collector that may be part of an integrated water separator. Specific details for implementing the invention

[0025] By incorporating the separation of water from the cathode of a fuel cell assembly in a fuel cell stack, the present disclosure teaches the use or capture of manifold space that was previously sacrificed for functional water separation. The smaller the footprint of the fuel cell power system, the less volume the fuel cell power system occupies when mounted in a vehicle or other use case. In some cases, the integrated water separator is less complex by utilizing the manifold as part of the encasement for the water separator.

[0026] FIG. 1 presents a flowchart (10) for the operation of a fuel cell stack having an integrated water separator. Fuel and air (oxidizer) (12) are fed into the fuel cell stack (13). If necessary, a liquid coolant (14), such as water, is fed into the fuel cell stack and distributed to the fuel cells within the fuel cell stack. The result of the electrochemical reaction occurring in the fuel cells is the generation of electricity (power), heat, and water vapor and liquid (16). The water vapor and liquid are collected within the fuel cell stack by a flow channel or other fluid connection to a stack collection location or manifold from each fuel cell forming the fuel cell stack. The present disclosure teaches the integration of a water separation device or water separation means for collecting water and then separating water vapor (18) from the liquid. The water vapor and other cathode air are exhausted from the stack (20). The collected liquid water (30) passes through either being distributed (31) to a fuel cell stack or being stored (32) and then distributed (33) to a fuel cell stack for humidification and cooling.

[0027] FIGS. 2 through 7 show a fuel cell stack with a water separation unit integrated therein. The fuel cell stack (100) is formed by stacking a plurality of fuel cell assemblies (115 / 115(1~N)) each having a membrane electrode assembly (MEA) (150), a gasket, and a bipolar plate. Typically, a flow field (not shown) will be formed within the bipolar plate, and a gas diffusion layer will be sandwiched between the MEA and the cathode and anode. However, gaskets and seals formed on a frame to seal the fuel cell assemblies into the fuel cell stack having only a predetermined manifold and / or fluid path are not shown.

[0028] FIG. 3a illustrates a plan view of a fuel cell assembly (115) showing an inlet and an outlet formed within a frame. At the first end of the fuel cell assembly, there is at least one water inlet (160), at least one air inlet (162), and at least one hydrogen outlet (164). At the second end, there is at least one hydrogen inlet (166) and one or more air exhaust ports (168) from the cathode. Additionally, a water outlet (170) is shown, and the water outlet is in fluid contact with the air exhaust port (168) area or manifold. Optionally, one or more additional manifolds (175) may be provided. One or more arrays (180) of fluid paths or connections are formed at the first end and provide fluid communication with the flow field below. One or more arrays (185) of fluid paths or connections are formed at the second end and provide fluid communication with the flow field below. FIG. 3b is a plan view presenting an alternative example (115') of a fuel cell assembly. In this example, one or more cathode air exhaust ports (168) are shown as being divided laterally by a bridge (192), thereby providing additional support across the opening. Although the bridge appears flat in the drawing, this is in accordance with a certain concept, and thus, the bridge may be claimed to be formed with a rib, formed with a dimple, or otherwise reinforced with an indentation or outdent when utilized. In this example, at least one air inlet (162) is shown as being divided laterally by a bridge (194), thereby providing additional support across the opening. Although the bridge appears flat in the drawing, this is in accordance with a predetermined design, and thus, when utilized, the bridge may be claimed to have ribs formed, concave portions formed, or otherwise reinforced with indentations or outdents.

[0029] FIGS. 4a through 5b illustrate embodiments of a fuel cell stack assembled within a fuel cell system (200). In FIG. 4a, the bottom (102) and top (104) of the fuel cell stack are shown. The fuel cell stack is illustrated as being compressed between a first end plate (201) covering the bottom (102) and a second end plate (210) covering the top (104). The designation of the top and bottom is for convenience only and is not intended to indicate orientation. The end plates and the fuel cell stack are configured to be assembled together. A plurality of fasteners (212) are generally used to further compress the fuel cell to ensure that all fuel cell assemblies are sealed together and do not leak. Fastening a fuel cell stack and a fuel cell system together is known in the art. The fastener (212) passes through both the first end plate and the second end plate and is secured by a nut (213) (shown in FIG. 5a) or a similar connecting means.

[0030] The second end plate (210) has a passage aligned with a water inlet, an air inlet, a hydrogen exhaust port, a hydrogen inlet, and an exhaust port from the cathode. The water inlet passage (220) is fluidly connected to at least one water inlet (160), the air inlet passage (222) is fluidly connected to the air inlet (162), and the hydrogen exhaust passage (226) is fluidly connected to the hydrogen exhaust port (164). The hydrogen inlet passage (236) is fluidly connected to the hydrogen inlet (166). The air exhaust port (168) is fluidly connected to the exhaust passage (238). A water exhaust port (170) that allows liquid water to be removed from the stack is also fluidly connected to the exhaust passage (238). The air exhaust duct or manifold (250) is fluidly connected to the collection cavity (300). An integrated water separator is presented. In some cases, the upper collector (400) is formed as part of the interior of the air exhaust manifold or is attached to the interior of the air exhaust manifold. The water collection lamp (252) is fitted into the collection cavity formed by the through air exhaust of each fuel cell assembly and the air exhaust (168) of each fuel cell assembly. The water collection lamp has an upper portion (253) and a lower portion (254). The air exhaust manifold has a body portion (260) and an outlet head (265). The outlet head is configured to be attached in various configurations to orient the open end (270) in a predetermined direction, from top to bottom, to the left, and to the right, at least partially to any direction corresponding to the outside of the fuel cell stack. Those skilled in the art will also understand that the entire water separator may be fitted into the collection cavity without departing from the scope of this disclosure. Optionally, as shown in FIG. 4b, a bifurcated region (240) may be formed as part of the second end plate. The additional area located between the large openings provides additional rigidity.In an optional system in which a bridge added to the exhaust passage (238) and / or fuel cell assembly (115') bisects, the water collection ramp (252') is grooved or divided along a substantial portion forming a gap to accommodate the bridge and / or bisect area (240). The bisected form has two bottom sections (254A and 245B) on both sides of the gap (250). A second gutter (412') for guiding the water collection (see FIG. 6a below) is provided.

[0031] FIGS. 5a and 5b illustrate embodiments of an assembled fuel cell system (200) having an integrated water separator. Those skilled in the art will understand that the dimensions of the fuel cell assembly may vary widely depending on the intended use and that the number of assemblies forming the stack may vary. However, such design variations will have common features within the scope of the present invention. It will have a manifold of a fluidly connected area through a plurality of fuel cell assemblies, said area will be configured for the insertion of a water separation means. A fastener (212) is generally used to compress the fuel cell assembly within the fuel cell system or to maintain the compressed state of the fuel cell assembly within the fuel cell system.

[0032] When in operation, the hydrogen inlet (166) receives a supply of hydrogen gas fuel distributed to the anode of the bipolar plate of each fuel cell assembly, and unconsumed hydrogen is present at the hydrogen outlet (164). Air is supplied to the cathode side of the bipolar plate of each fuel cell assembly through the air inlet (162). Water is supplied to the fuel cell assembly through the water inlet (160) and is removed as liquid water and water vapor through the air exhaust (168). When stacked, the air exhaust of the fuel cell assembly forms a collection cavity (300) for removing water and water vapor from the fuel cell stack. The collected liquid water can be removed through one or more water discharges (170). This water can be recycled to the fuel cell stack for cooling and humidification as needed.

[0033] FIGS. 6a through 6d present an internal water separator having a collection ramp (252) configured to be fitted into a collection cavity (300) formed by a plurality of air exhausts of each stacked fuel cell assembly. The water collection ramp performs at least one of collecting, capturing, condensing, cooling, and redirecting water exiting from the cathode flow field of each fuel cell assembly as a cathode exhaust, and forces the water toward the bottom (102) of the fuel cell stack through gravity and surface tension. The water collection ramp or part thereof (including a gutter) may be a plate or a plurality of plates and may be porous or textured to capture and move the water. The water collection ramp or part thereof (including a gutter) may have surface features including, but not limited to, one or more of, pins, bumps, protrusions, divots, channels, or grooves to guide the captured water. A water collection lamp or a part thereof (including a gutter) may be composed of multiple parts and may be made of a heterogeneous material. Such material may be uniform in terms of lubricity, smoothness, or roughness, or may be non-uniform in terms of lubricity, smoothness, or roughness. The material may have surface features that resist bacterial, algae, and microbial growth or antimicrobial agents embedded within it. One side of the water collection lamp may exhibit a variety of sets of features, including but not limited to texture, smoothness, lubricity, and / or grooves, channels, dimples, divots, etc., unlike the other side.

[0034] In some cases, the water collection lamp or part thereof (including the gutter) is hydrophilic. In some cases, the water collection lamp or part thereof (including the gutter) has both hydrophilic and hydrophobic regions. In some cases, the water collection lamp or part thereof (including the gutter) can act as a heat sink for liquid water and water vapor in the air exhaust to further promote condensation.

[0035] The water collection lamp (252) has a first surface (402) and a second surface (404). One surface faces the exhaust port coming from each fuel cell assembly, and the other surface is on the opposite side of the exhaust port. A raised gutter (405) may be formed on one or both of the first surface and the second surface. Although the gutter is depicted as being attached to the spine (410) at the first gutter end (412) and the second gutter end (414) is not attached, those skilled in the art will understand that the first gutter end may not be attached to the spine. Those skilled in the art will also understand that the angle of the gutter relative to the spine is not limited as illustrated by example, and the scope of the present disclosure includes varying the angle of all gutters relative to the spine or varying the angle of some of the gutters. The present disclosure also includes a variable-angle gutter array in which various gutters have different angles relative to the spine. Subsequently, the different angles will represent varying velocities of the flow of water collected by the gutter. The water collection ramps may be tuned to handle fluid volumes and flow rates of exhaust from multiple fuel cell assemblies, each of which adds heated exhaust into the collection cavity, causing the heated exhaust to rise from the bottom of the fuel cell (102) toward the top (104). Additional ramps may be inserted with spacing between the ramps. Those skilled in the art will understand that one or more additional spines may be extended to the length of all or some of the ramps, and that such modifications are within the scope of this disclosure.

[0036] In some cases, the gutter may have perforations, may not extend across the entire width of the gutter, or may have gaps between the walls. In other cases, the gutter is at least partially undulating and not straight. The angle (420) of the bottom of the water collection ramp (254) relative to the floor (302) of the collection cavity is constant in a predetermined configuration. The angle of the water collection ramp is tuned to collide with heated exhaust from a plurality of fuel cell assemblies fluidly connected to the collection cavity, each while heated air, water, and steam are flowing into the collection cavity. This angle setting may be tuned to reduce any pressure difference between fuel cell assemblies within the fuel cell stack due to the position of the fuel cell assembly relative to the top or bottom of the fuel cell stack. Accordingly, those skilled in the art will understand that the aforementioned angle setting may be changed if the type of number of fuel cell assemblies changes or if the amount of exhaust air differs, and such changes will be within the scope of this disclosure.

[0037] In some cases, the gutter has a jagged or serrated edge (430) opposite the spine (410). The gutter is illustrated as an “L” shape having a first leg (412) connected to a water collection ramp and a second leg (414) connected to the first leg and having a free end (415). In operation, the above method acts so that the free end (415), configured to guide the collected water to the jagged edge (430), guides the water toward the free end. The water guided to the jagged end (430) falls into a predetermined area aligned with the jagged end (430) for collection. Those skilled in the art will understand that the “L” shape is merely an illustrated example and is not intended to be limiting. The collection area guides the water on the water collection ramp to a predetermined location. The above-mentioned gutter may be "U" shaped or "V" shaped, or any of the various shapes for guiding and collecting water, and a gutter of such shape will be within the scope of the present disclosure. The gutter is also configured to increase the surface area of ​​the water collection ramp to provide more opportunities to collect water. Those skilled in the art will understand that the aforementioned teeth are merely illustrated examples, and that curved edges or straight edges in place of such teeth are also within the scope of the present disclosure. Furthermore, the same toothed edge illustrated as extending along the length of the water collection ramp is not intended to be limiting, and in some cases, the toothed edge may extend over only a portion of the length of the water collection ramp.

[0038] Optionally, an upper collector (450) is formed as part of the exhaust port body portion (260) or is attached to the exhaust port body portion (260). The upper collector has a surface (452) facing the collection cavity where a ridge or fin (455) extends, and the extended fin (455) is configured to have an additional surface area for collecting water within the air exhaust port, water exhaust port, and steam exhaust port and for directing the collected water downward to the water collection ramp. In some cases, the ridge or fin (455) has one or more of a protrusion, divot, channel, and groove thereon. In some cases, the fin (455) is composed of multiple parts. In some cases, the fin has at least one of a predetermined surface lubricity and surface roughness. In some cases, the fin is either hydrophobic or hydrophilic. In some cases, the fin has at least one area that is more hydrophilic or more hydrophobic than another part. In some cases, the pin has both hydrophilic and hydrophobic regions. In some cases, the pin has at least some textured regions, and in other cases, the pin is textured.

[0039] The method disclosed herein is a method of reusing wasted manifold space within a fuel cell stack for other purposes to act as an isolator for a water separator in order to reduce the footprint of the fuel cell system. Using the fuel cell as an isolator also simplifies the water separator and reduces the cost and complexity of the water separator.

[0040] The systems described throughout this disclosure may be utilized in various applications to provide power generated by fuel cell systems. In some embodiments, the systems disclosed throughout this application may be used in machine handling equipment, such as forklifts. In some embodiments, such systems may be used in unmanned aerial vehicles (UAVs), such as fixed-rotor drones or multi-rotor drones. In some embodiments, the systems disclosed herein may be used in automotive applications, such as passenger cars. In some embodiments, the systems disclosed herein may be used in stationary power applications. In some embodiments, the systems disclosed herein may be used in the aviation sector. It will be understood that such systems may be used in various other applications, and that specific functions and physical parameters, such as component sizes and quantities, may be modified to suit specific applications and specified by the requirements for specific uses. Additional advantages as described above include the ability to assemble the system and related components (e.g., fuel canister cylinders) in a smaller space and to arrange the system and related components.

[0041] The components disclosed herein may utilize known materials used in industry.

[0042] As will be understood by those skilled in the art, throughout this specification, the ordinary meanings of the words shall be given. However, to avoid misunderstanding, the meanings of specific phrases may be specifically defined or specified.

[0043] Although the present disclosure has been described in connection with various embodiments of the various drawings, those skilled in the art will understand that modifications to the foregoing embodiments may be made without departing from the broad concept of the invention of the present disclosure. Accordingly, it will be understood that the present disclosure is not limited to the specific embodiments disclosed, but is intended to encompass modifications that fall within the spirit and scope of the present disclosure as defined by the claims.

[0044] The features of the present disclosure described above in the context of individual embodiments may be provided in combination in a single embodiment. Conversely, the various features of the present disclosure described in the context of a single embodiment may also be provided individually or in any sub-combination. Finally, while an embodiment may be described as part of a series of steps or part of a more general structure, each step may also be considered as an independent embodiment that can be combined with others.

[0045] References to ranges of values ​​herein are intended merely to function as a shorthand method for individually referring to each individual value within the said range, unless otherwise specified herein, and each individual value is incorporated into this specification as if individually cited herein. All methods described herein may be performed in any suitable order, unless otherwise specified herein or otherwise clearly contradictory by the context.

Claims

Claim 1 A fuel cell system comprising a plurality of fuel cell assemblies configured to be compressed together to form a stack having an upper and a lower portion, wherein each fuel cell assembly comprises: one or more frames configured to support a membrane electrode assembly (MEA); at least one hydrogen outlet configured to collect hydrogen from the anode side of the MEA; at least one cathode outlet configured to collect at least air and water from the cathode side of the MEA, wherein the cathode outlet of the fuel cell assembly is configured to form a collection cavity having a floor within the fuel cell stack and is fluidly connected to each fuel cell assembly; a water outlet fluidly communicating with the collection cavity; and a collection ramp configured to be fitted inside the collection cavity. Claim 2 A fuel cell system according to claim 1, further comprising a cathode flow field configured to distribute oxygen across the MEA from at least one air inlet formed within the frame. Claim 3 A fuel cell system according to claim 1, further comprising an anode flow field configured to distribute hydrogen across the MEA from one or more inlets formed within the frame. Claim 4 A fuel cell system according to claim 1, further comprising at least one gas diffusion layer adjacent to at least one of the cathode flow field and the anode flow field. Claim 5 A fuel cell system according to claim 1, further comprising one or more inlets formed in each frame and configured to supply hydrogen to the anode side of the MEA. Claim 6 A fuel cell system according to claim 1, further comprising one or more inlets formed in each frame and configured to supply air gas to the cathode side of the MEA. Claim 7 A fuel cell system according to claim 1, further comprising one or more inlets formed within each frame and configured to supply water to at least the cathode side of the MEA. Claim 8 A fuel cell system according to claim 1, wherein the collection lamp further comprises a first surface, a second surface, a first edge, a second edge, an upper portion, and a lower portion, and is configured to be fitted inside the collection cavity to collect water from the cathode exhaust port. Claim 9 A fuel cell system according to claim 7, further comprising a gutter extending from at least one side of the collection lamp. Claim 10 A fuel cell system according to claim 8, further comprising a spine attached longitudinally to the first edge; and a tooth formed on the second edge, wherein the gutter is attached to the spine at one end, and water collected on the collection lamp falls from the gutter to the toothed edge. Claim 11 A fuel cell system according to claim 8, wherein at least one of the collection lamp and the gutter comprises at least one of a texture, a bump, a protrusion, a divot, a channel, and a groove. Claim 12 A fuel cell system according to claim 1, wherein the cathode exhaust port is divided and the collection lamp is divided so as to be fitted therein. Claim 13 A fuel cell system according to claim 1, further comprising an air manifold in fluid communication with the collection cavity. Claim 14 A fuel cell system according to claim 1, further comprising an upper collector formed as part of the exhaust manifold or attached inside the exhaust manifold, wherein the upper collector is configured to have a fin facing a collection cavity inside the exhaust manifold, and water collected on the fin during operation is guided to the collection lamp. Claim 15 A fuel cell system according to claim 1 or 13, wherein at least one outer surface of the upper collector and the collection lamp has a predetermined surface lubricity or surface roughness. Claim 16 A fuel cell system according to claim 1 or 13, wherein at least one outer surface of the upper collector and the collection lamp is one of hydrophobic and hydrophilic. Claim 17 A fuel cell system according to claim 8, wherein the collection lamp is attached within the collection cavity at a certain angle with respect to the floor of the collection cavity. Claim 18 A method for separating water in a fuel cell system integrated into a fuel cell stack, comprising the steps of: compressing a plurality of fuel cell assemblies together to form a fuel cell stack; aligning the cathode exhaust ports of the fuel cell assemblies to form a collection cavity within the fuel cell stack that is fluidly connected to each fuel cell assembly; arranging a water outlet that is fluidly connected to the collection cavity; and arranging a water collection ramp within the collection cavity.

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