Fluid guiding assembly

Abstract

A fluid guiding assembly for a fuel cell comprises a channel structure (720) and a gas diffusion layer (5) arranged on the channel structure (720), the channel structure (720) defining flow field channels (72) extending from a first end to an opposite second end of the channel structure (720), wherein both ends of the channel structure (720) are arranged with a porous distributor (73) extending over the entire width of the channel structure (720).

Description

Technical Field

[0001] This invention relates to a fluid guiding assembly, particularly for guiding gas and liquid in a fuel cell. Background Technology

[0002] Fuel cells are one of the leading candidates to replace fossil fuel-based generators, and they can be used in a number of applications, including mobile and stationary applications. One such fuel cell is the proton electrolyte membrane (PEM) fuel cell, which operates at 70°C–80°C. Individual cells in a stacked assembly include an electrolyte (typically a thin film), a catalyst layer on the anode side, and a catalyst layer on the cathode side; this assembly is referred to as a membrane electrode assembly (MEA). Fuel (typically hydrogen) and an oxidant (typically air) pass through the layers, where electrochemical reactions occur to generate electricity, with water as a byproduct. A gas diffusion layer (GDL) made of porous carbon fibers is typically present, sandwiched between the MEA and a flow field (FF) plate with special flow channels for uniform gas distribution. Water generated on the catalyst layers passes through the GDL until it reaches the gas channels, where it is expelled from the cell. Phase change and water and thermal management in fuel cells have been extensively studied in recent years, and several patents have been filed in this area. However, challenges remain regarding simplification, compactness, cost reduction, and ease of fabrication. A simple example can be used to illustrate the limitations of existing fuel cell technology. Patent application US9947943 relates to the design and manufacture of fuel cell stacks for (primarily) sheet metal-based automotive applications. Considering an approximate 300 cm² spacing between individual cells with a spacing of approximately 1.1 mm... 2 The active region. The thickness of each cell is mainly determined by the thickness of the plate. Therefore, it is limited by stamping technology. In order to provide a more competitive product to the market, it is important to increase the "volume power density" of the stack and make them more compact. This is not possible using existing stamping technology for metal plates and compression / injection molding for graphite plates, so other production methods should be sought. For example, examples of such flow structures are disclosed in US20190242021 and US20150118595. Summary of the Invention

[0003] The problem to be solved in this invention is to provide fluid guiding components that allow for the production of thinner fuel cells. Furthermore, these fuel cells should have a simple design and be easy to manufacture.

[0004] The fluid guiding assembly for a fuel cell according to the present invention includes a channel structure and a gas diffusion layer disposed on the channel structure. The channel structure defines a flow field channel extending from a first end of the channel structure to an opposite second end. A porous distributor is disposed at both ends of the channel structure, extending across the entire width of the channel structure from a first lateral side to an opposite second lateral side.

[0005] This design allows for a reduction in the thickness of the fluid guiding component, thereby reducing the thickness of the fuel cell using it. A thickness reduction of nearly 50% can be achieved while simultaneously improving cell performance. Furthermore, the gas diffusion and heat transfer rates of the fluid guiding component are significantly increased. Moreover, the production cost of this component is lower, resulting in lower production costs for fuel cells incorporating it.

[0006] In one embodiment, the dispenser is formed as a single piece and has a porosity between 10% and 90%. In another embodiment, the porosity varies between 50% and 80%.

[0007] In one embodiment, porosity varies across the width of the manifold; that is, when the fluid guiding assembly is introduced into the fuel cell, the porosity near the corresponding manifold is lower than the porosity further away from that manifold. For example, if the manifold is distributed on one lateral side, the porosity is minimum there, and maximum on the opposite lateral side. If the manifold is distributed in the middle, the porosity is highest on both lateral sides and minimum in the middle.

[0008] In one embodiment, the length of the distributor is in the range of 1% to 10% of the length of the flow field channel (i.e., the channel structure).

[0009] In one embodiment, the length of the dispenser ranges from 0.1 mm to 20 mm. In another embodiment, the length of the dispenser ranges from 1 mm to 10 mm.

[0010] In one implementation, the height of the distribution element is equal to the height of the channel structure.

[0011] In one implementation, the height of the distribution element is less than the height of the channel structure.

[0012] In one implementation, the height of the distributor is equal to the sum of the height of the diffusion layer and the height of the channel structure.

[0013] In one implementation, the height of the distribution component is greater than the height of the channel structure.

[0014] In one embodiment, the height of the dispenser is in the range of 50 micrometers to 400 micrometers. In another embodiment, the height of the dispenser is in the range of 200 micrometers to 400 micrometers.

[0015] In one implementation, the flow channel structure and the distribution component are permanently connected to each other.

[0016] In one embodiment, the gas diffusion layer, flow channel structure, and dispensing element are permanently connected to each other. This permanent connection can be achieved by coating, pressing, or hot pressing.

[0017] In one embodiment, the dispenser includes at least one of the group consisting of open-cell foam, hole pattern, and slit pattern.

[0018] In one embodiment, the dispenser includes circular, elliptical, or angled holes.

[0019] In one embodiment, the dispenser includes a straight, curved, or angled slit.

[0020] In one embodiment, the dispenser is made of metal, plastic, or resin, or a combination thereof.

[0021] In one embodiment, the channel structure includes straight, serpentine, or intersecting flow field channels.

[0022] In one implementation, the channel structure and distribution components are integrated into a single unit.

[0023] The features of the above-described embodiments of the fluid guiding component can be used in any combination unless they contradict each other.

[0024] The flow field structure according to the invention includes a fluid guiding assembly as described in any of the foregoing embodiments and a baffle having a recess for receiving the fluid guiding assembly. The flow field structure also includes a manifold and a distribution channel for supplying gas to a distributor at a first end of the channel structure and collecting gas from the distributor at a second end of the channel structure.

[0025] The fuel cell according to the present invention includes at least one membrane electrode assembly supported by two flow field structures according to the foregoing embodiments.

[0026] In one embodiment, the fuel cell includes two current collector plates and two backplates, wherein one current collector plate is arranged adjacent to each flow field structure, and wherein one backplate is arranged adjacent to each current collector plate.

[0027] In another embodiment, the two back plates are supported by clamping elements.

[0028] A method of manufacturing a fluid guiding assembly according to the present invention includes the following steps:

[0029] - Provide channel structure;

[0030] - Provide porous distribution elements at both ends of the channel structure; and

[0031] - Provide a gas diffusion layer on the channel structure.

[0032] In one implementation, the method includes the following steps:

[0033] - Permanently connect the channel structure to the two distribution components.

[0034] In one implementation, the method includes the following steps:

[0035] Simultaneously or after connecting the channel structure and the distribution components.

[0036] - Permanently connect the gas diffusion layer to the channel structure and the two distribution components.

[0037] In one embodiment, the permanent connection includes pressing, or the permanent connection includes heating and pressing.

[0038] The features of the above-described embodiments of the manufacturing method can be used in any combination unless they contradict each other. Attached Figure Description

[0039] Embodiments of the invention will now be described in more detail with reference to the accompanying drawings. These embodiments are for illustrative purposes only and should not be construed as limiting. In the drawings,

[0040] Figure 1 This is a top view of a flow field plate based on existing technology;

[0041] Figure 2 This is a top view of the flow field structure according to the present invention;

[0042] Figure 3 yes Figure 2 A partial cross-sectional view of the flow field structure along section line XX;

[0043] Figures 4A to 4B This is a cross-sectional view of an embodiment of the distribution component according to the present invention;

[0044] Figures 5A to 5B This is a partial three-dimensional view of the implementation method of the flow field channel;

[0045] Figure 6 A cross-sectional view of a membrane electrode assembly supported by two flow field structures according to the invention; and

[0046] Figures 7A to 7H The manufacturing process of one embodiment of the fluid guiding assembly according to the present invention is described. Detailed Implementation

[0047] Figure 1A top view of a flow field plate according to the prior art is shown. The bipolar plate 7, made of any material such as metal or graphite, includes several gas / liquid inlet / outlet manifolds 90, 91, 92 located outside the plate. An active region A with a catalyst layer is located in the middle of the cell, with a specific flow field (FF) below. The flow field ensures a sufficient and consistent gas supply to the active region A. A flow distribution channel (FDC) is located between the inlet and outlet manifolds, guiding the gas so that it is consistently distributed across the flow field and the active region. In fuel cells, regardless of the bipolar production method (composite graphite or metal), a consistent gas flow field is typically present in the active region to distribute the gas uniformly across the catalyst layer. In a stacked assembly, there are inlet and outlet manifolds connected to each cell for gas supply. After the gas / liquid enters the cell, it needs to be consistently distributed within the cell before reaching the active region. Typically, this is achieved using a flow distribution channel 71 located between the active region A and the corresponding inlet manifold 91. Similarly, a special flow pattern exists between the active region and the outlet manifold to avoid unnecessary back pressure and flow disturbances on the battery. For consistent gas flow distribution, adequate water management, and sufficient reactant supply to the catalyst layer, gas flow channels are designed on or within the channel structure. These channels guide the reactants to flow in a specific direction and facilitate water removal from the battery. Various methods for manufacturing flow channels or patterns are used depending on the material used to manufacture the plates. For example, if the plates / separators are made of graphite composites, injection molding, compression molding, or machining are used. If the plates are made of sheet metal, stamping is the most promising and economically feasible technique already in use. For each mono- and bipolar plate assembly, typically two separate metal sheets are stamped, laser-welded, and coated with a protective coating (before or after stamping). In some cases, laser welding is eliminated, and conventional sealing is used. One of the main drawbacks of existing designs is the limitation on how much the thickness of individual plates can be reduced. This has a direct impact on the dimensions of the assembled stack and therefore on the volumetric power density. On the other hand, the width and depth of the channels that can be produced are limited by the elongation of the metal plates or the machining process. The gas channels are separated from each other by ribs that contact the gas diffusion layer (GDL). Water generated by the electrochemical reaction passes through the GDL and eventually enters the gas channels. One of the main limitations of plates produced by graphite or stamping techniques is that the width of the contact ribs (sometimes called "land") cannot be reduced to less than 1 mm–2 mm. As a result, the ribs are one of the main sources of water accumulation in the battery, which degrades battery performance and also increases the corrosion rate on the plate. To overcome this problem, porous media have been used as gas flow channels. However, the limitation of this structure is that there is no control over the direction of gas flow, which limits battery performance and increases water accumulation in dead zones (e.g., at the corners of the battery), especially under dynamic load operation.Alternatively, if parallel fine wires are used to create gas channels, several other wires are vertically mounted on top of them to serve as a gas diffusion layer (GDL), thus forming a grid. With this design, 50% of the active area is blocked, where the wires are in contact with the active area. Furthermore, even with fixing and automated devices, placing and connecting such a large number of tiny wires together is extremely tedious and time-consuming. Connecting them by welding in the case of metal wires, or by thermal fusion in the case of plastic wires, is a very difficult task. Quality control of this assembly is difficult, and it is likely that some channels / holes will be blocked, which will create hot spots on the membrane and damage it. In addition, another gas delivery mechanism is needed to deliver gas to the active area and the grid. If some of these wires contact each other at the edges of the assembly, they will obstruct gas flow and cause gas inconsistency. In an alternative embodiment, a braided grid is used as the gas diffusion layer. The consistent gas distribution within the active area is limited with this design. Therefore, gas diffusion into and out of the cell is also restricted due to the large pressure drop generated by the grid structure and its influence on capillary forces. A conventional method for producing a gas diffusion layer (GDL) is a combination of a microporous layer and carbon fibers on one side of the GDL, where the GDL is in direct contact with the catalyst layer in the cell assembly. GDLs from Freudenberg or Toray are some existing technologies on the market. Typically, the GDL is compressed between the flow channels of the bipolar plate and the membrane electrode assembly (MEA) on both the anode and cathode sides.

[0048] Figure 2 A top view of the flow field structure 7 according to the present invention is shown, and Figure 3 It shows Figure 2A partial cross-sectional view of the flow field structure along section line XX. The structure of the present invention integrates several components within a fuel cell in a more compact and reliable manner. Together, it includes a unique prior art channel structure 720, a gas diffusion layer, and a gas distributor 73. It not only overcomes the disclosed problems associated with the prior art but also significantly improves the performance of the fuel cell. At the same time, this design simplifies the battery assembly, thus providing compactness, reliability, and significant cost reduction in fuel cell production. In the illustrated embodiment, the channel structure 720, including the flow field channel 72, is located at the center of the assembly (i.e., in the active region A of the fuel cell). Two separate distributors 73 are present. Each distributor is fixed to one end of the channel structure 720. They serve as mechanical supports during the production process and ensure consistent gas distribution before the gas enters the active region A. Furthermore, a thin layer serving as a gas diffusion layer 5 is present on top of the channel structure 720. This design has several functions and advantages. First, it is very compact and has a lower manufacturing cost compared to existing concepts. Secondly, it functions as a flow straightener for active region A, ensuring a uniform gas flow distribution before the gas enters active region A. Thirdly, in the case where the channel structure 720 is made of a separator such as a wire, it functions as a mechanical support, holding the separator in place and subjecting it to tension. Fourthly, it allows for a smaller and more compact overall battery assembly, including the plates.

[0049] like Figure 3 As shown, there are no limitations on the size and dimensions of the dispenser 73, and it can vary based on the size of the battery, separator 70, and active region A. The length of the dispenser 73 is preferably 1%-30% of the length of the flow channel 72, more preferably 1%-10%, but not limited thereto. For example, if the length of the flow channel 72 is 100 mm, the preferred length of the dispenser can be between 1 mm and 10 mm.

[0050] The thickness of the distributor 73 is preferably close to or slightly larger than the thickness of the channel structure 720. Since the distributor 73 can serve as a mechanical support and holder for the channel structure 720, it may be necessary to make the distributor slightly thicker so that the interface between the channel structure 720 and the distributor 73 can be positioned on top of it. For example, if the thickness or height of the channel structure 720 is 200 μm, the thickness or height of the distributor can vary between 200 μm and 400 μm, but is not limited to this. Such a design provides greater flexibility for the battery assembly, especially when the distributor 73 is in direct contact with the catalyst coating film (CCM) or sub-pads or any other component of the battery assembly. This design results in a smaller plate and therefore a smaller overall battery size (active area + surrounding sub-pads), which in principle reduces the stack size and manufacturing costs. Figure 2The layout of a battery having a dispensing member 73 according to the invention is shown. (Compared to...) Figure 1 Compared to the original plate design shown, the length of partition 70 is reduced. Figure 1 The board and Figure 2 The main difference between the plates is that the active region A and the gas inlet / outlet manifolds 90, 91, 92 remain the same, while according to the invention, the area where the distributor is located is conceptually significantly optimized and shortened. For example, the oxidant enters the battery from the oxidant manifold 91 and is distributed in the distribution channel 71 as shown by the arrows in the figure. It then reaches the distributor 73, where the airflow is regulated and homogenized before entering the flow field channel 72 and the active region A. The length of the distribution channel 71 is optimized based on the battery design and geometry. It should not be too long to prevent the generation of large back pressure. Similarly, it should not be too small, otherwise the assembly layers on top (such as catalyst coating films or sub-gaskets) may deform and clog the distribution channel 71. Alternatively, the distributor can extend along the entire length of the distribution channel between the channel structure 720 and the corresponding manifold 91. These are design parameters that can be adjusted by those skilled in the art.

[0051] Figures 4A to 4B A cross-sectional view of an embodiment of the dispenser 73 according to the invention is shown. The dispenser 73 can be made of various materials, such as metals (aluminum, titanium), plastics, thermoplastics, resins, or porous components, but is not limited thereto. The structure of the dispenser is adjusted based on the material used in its production. There are no limitations on the design of the dispenser or its manufacturing method. For example, it can be made of porous resin, metal, or other materials. The porosity of the dispenser should be estimated based on the design and size of the battery, preferably between 10% and 90%, more preferably between 50% and 80%, but is not limited thereto. Very high porosity is not recommended because it reduces mechanical stability, and very low porosity is also not recommended because it will generate a very large pressure drop across the dispenser, and therefore a very large pressure drop across the fuel cell. If the dispenser is not made of a porous material itself, other manufacturing techniques, such as 3D printing, injection / compression molding, lamination, etching, or any other method, can be used. For example, porosity can be generated by a plurality of pins 730 extending through the dispenser 73 or by a plurality of slits 731 extending through the dispenser 73. Figure 4A In the illustrated embodiment, pins 730 are evenly distributed across the cross-section of the distribution member 73. Figure 4B In the illustrated embodiment, the slits 731 are serpentine and evenly distributed across the width of the cross-section of the dispenser 73. The dispenser 73 can be used with a partition 70 made of metal, graphite, or other materials. The materials of the dispenser 73 and the channel structure 720 need not be the same. For example, by introducing the dispenser according to the invention into the channel between the channel structure and the corresponding manifold, the number of slits can be reduced or eliminated. Figure 1The flow path of a conventional fuel cell is shown.

[0052] Figures 5A to 5B A partial perspective view of an embodiment of the flow field channel 72 in the corresponding channel structure 720 is shown. In the depicted embodiment, the flow field channel 72 is generated by stamping a thin metal sheet. In this case, the channel structure 720 is integrally formed as a single piece with the partition 70. Therefore, the distributor 73 is adjacent to either the flow channel structure 720 or the partition 70. In a fuel cell, fresh oxidant (mainly air) diffuses through the gas diffusion layer to the catalyst layer. Water generated on the catalyst layer moves towards the channel due to capillary forces in the gas diffusion layer. Within the channel, condensate and oxidant mix, and the generated water is expelled from the channel. The gas velocity in the channel is the primary cause of the behavior of the fresh oxidant, the movement of water, and the mixing phenomena that occur in the channel. The gas flow in a fuel cell is primarily laminar. However, different mixing mechanisms may occur between the gas and condensate based on the Reynolds number. For example, a gas / liquid mixture with a Reynolds number of 1000 differs from a gas / liquid mixture with a Reynolds number less than 500. High gas flow velocities help to expel condensate from the flow field channel. However, due to complex mixing effects, fresh air can be prevented from reaching the active region, especially towards the outlet side of the channel where water accumulation occurs. To address this issue and improve water management in the gas channel, it is important to distinguish between conventional mixing and diffusion mixing. In diffusion mixing, the liquid and gas remain separated from each other before and during the transition zone. Diffusion mixing is directly related to fluid flow, Reynolds number, and Prandtl number. Therefore, the dimensional design of the flow field channel 72 and the gas diffusion layer 5 should be completed in a manner that takes into account the phenomena of conventional mixing and diffusion mixing. Thus, the ratio of Reynolds number to Prandtl number should be, for example, in the range of 0.01 to 1000, and more preferably 0.05 to 500, but is not limited thereto.

[0053] exist Figure 5BIn this embodiment, multiple wires 720 are aligned with each other at equal distances to form flow field channels 72. The distance between two adjacent wires is preferably from 10 μm to 1000 μm, more preferably from 100 μm to 300 μm, but is not limited thereto. The preferred cross-section of the wire is one of a circle, a square, or a rectangle, but is not limited thereto. In the case of a circular wire, the preferred diameter is between 10 μm and 500 μm, and more preferably between 100 μm and 300 μm. In the case of a square wire, the preferred side length is between 10 μm and 500 μm, and more preferably between 100 μm and 300 μm, but is not limited thereto. Similar structures can be manufactured using other methods, such as laser cutting, but are not limited thereto. The wires can be made of a variety of materials, and there are no limitations as long as the material is conductive. Some examples of materials that can be used are stainless steel, aluminum, titanium, copper, or thermoplastics such as PET, PEN, epoxy resin, polyurethane resin, polyamide resin, acrylic resin, carbon, carbon fiber, or any other material. Regardless of the material used, an anti-corrosion protective coating can be applied to prevent corrosion. Specific materials that can be used include gold, silver, copper, aluminum, platinum, and ruthenium, and can be applied using methods such as DLC, CVD, or PVD coatings. Furthermore, if the wires are made of non-conductive materials such as thermoplastics, a conductive coating should be applied to enable them to function in the assembly. However, it may be less conductive than wires made of materials from non-conductive materials. There are no limitations on the materials used as conductive coatings. For example, carbonaceous materials bonded to binders such as PVDF or PTFE, or conductive particles such as Au, Ni, or palladium, can be used, but are not limited to these.

[0054] Figure 6A cross-sectional view of a membrane electrode assembly supported by two flow field structures according to the invention, which can be used in a fuel cell 1, is shown. The membrane electrode assembly includes a membrane 2 supported by an anode electrode layer 3 and a cathode electrode layer 4. A first flow field structure 6 and a second flow field structure 7 each include baffles 60, 70, channel structures 620, 720, distributors 63, 73, and gas diffusion layers 5 arranged in corresponding recesses in the corresponding flow field structures. Each channel structure 620, 720 includes a corresponding flow field channel 62, 72. In the illustrated embodiment, each flow field structure 6, 7 includes distribution channels 61, 71 connecting the distributors 63, 73 to a corresponding manifold 91. The gas diffusion layer 5 used in this invention is thinner than conventional gas diffusion layers, and its thickness is preferably between 10 μm and 150 μm, more preferably between 25 μm and 65 μm, but not limited thereto. By introducing a gas diffusion layer between the channel structure 720 and the catalyst layers 3, 4, gases and water will have sufficient space to pass through without being blocked. Furthermore, the very narrow contact ribs between the layers completely eliminate water accumulation at the contact points. The gas diffusion layer 5 used in this invention serves as a mechanical support for the channel structure 720, and vice versa. Due to the very small structure forming the flow field channel 72 and the small thickness of the gas diffusion layer 5, double-sided supports are possible. As can be understood, handling and manipulating layers of 25 μm to 65 μm and flow channels with a thickness of approximately 200 μm is extremely cumbersome. However, the current structure provides a reliable means of achieving this. The gas diffusion layer can be made of any matrix, as long as it has a porous structure for the diffusion of oxidant and fuel from and to the catalyst layer. It should also have excellent electrical conductivity to reduce the resistance between layers. Several matrices exist that can be used as conductive particles. Some known and prior art materials are carbon, carbon black, carbon powder, carbon particles, carbon paper / cloth, or any other material. It is also preferred that the mixture includes a matrix with hydrophobic properties. The hydrophobic matrix acts as a binder in the mixture and holds the structure together after its curing. It also helps to push water towards the gas channels. Some existing hydrophobic particles that can be used are PVDF, PTFE, or any other material from a similar family. There is no limitation on the amount of binder in the mixture. However, a recommended mass percentage is preferably between 5% and 80%, more preferably between 10% and 30%, but not limited thereto. To increase conductivity, additional matrix can be added to the mixture. Some examples are gold, platinum, ruthenium, or any other material from the same family. As mentioned earlier, due to the thickness of the gas diffusion layer, it is preferable to manufacture it together with the flow field channels. Several methods exist for producing the gas diffusion layer. For example, it can be produced by touch coating, screen printing, 3D printing, or other methods, wherein the composition and viscosity of the mixture should be adjusted for each machine used.

[0055] Figures 7A to 7HA diagram illustrating the manufacturing process of one embodiment of the fluid guiding assembly according to the present invention is shown. Those skilled in the art will understand that this is merely an example, and several other techniques may be proposed. Below, the necessary steps for producing a structure including flow field channels, gas diffusion layers, and distribution elements that can be directly used within a battery assembly are described.

[0056] Step 1 - Figure 7A To form the flow field channel 72 of the fuel cell, several wires are arranged side by side. The structure of the channel is not limited and can be parallel, serpentine, intersecting, or a combination thereof.

[0057] Step 2 - Figure 7B To form a fixing device to precisely position and hold the wire in place. Several methods exist for manufacturing the fixing device, such as 3D printing, machining, or any other method.

[0058] Step 3 - Figure 7C Once the wire is secured and kept taut, two distribution pieces 73 are set and secured at the ends of the wire, i.e., at the inlet and outlet of the flow channel 72.

[0059] Step 4: Depending on the materials used, these sheets can be joined together using several methods, such as hot pressing. Thus, the assembly is placed under pressure at a fixed temperature for an extended period of time.

[0060] Step 5: After combining these sheets, cool them to room temperature, and then apply the gas diffusion layer 5. Several possibilities exist; for example, a conventional gas diffusion layer 5 can be used, or a paste can be applied to the top of the flow channel 72 using screen printing or other techniques.

[0061] Step 6: After applying gas diffusion layer 5, hold the assembly at room temperature and perform quality control procedures to verify the accuracy and uniformity of the layers and structure.

[0062] Step 7: Place the components in an oven for curing. Several options are possible depending on the materials used on the channel structure 720 and the gas diffusion layer 5. For example, a conventional oven, an infrared oven, or a UV oven can be used. When using a paste as the gas diffusion layer 5, for example, the structure is heated to a temperature of approximately 350°C to cure the mixture and adhesive.

[0063] Step 8: After firing the components, remove them from the oven and cool them to room temperature.

[0064] The structure is intended to be installed in a battery assembly. Similar components can be used on both the anode and cathode sides, or they can be different; for example, the structure on the cathode side can have larger flow channels to reduce pressure drop, or they can have different gas diffusion layers for various applications.

[0065] As a practical example, in order to produce an active area of ​​50×50 mm 2 For the single-cell assembly, the following components were selected. For the distribution pieces 63 and 73, a resin-type material with a porosity of approximately 75%, a height of 2 mm, a length of 5 mm, and a width of 50 mm was prepared. For the channel structures 620 and 720, carbon fiber wires with a diameter of 0.4 mm and a length of 55 mm were prepared and positioned at the same distance from each other at 0.3 mm intervals. For the gas diffusion layer 5, carbon black powder, PTFE dispersion, and surfactant were mixed together, wherein the percentage of carbon black and PTFE was maintained between 80% and 20%. These sheets were assembled together using a fixing device. The gas diffusion layer paste was applied to the channel structure using a screen printing machine, and the assembly was placed in an oven at 350°C for up to 15 minutes. A similar process was repeated for the second structure on the anode side of the cell. A flat compressed graphite plate with a thickness of 4 mm was used as a separator. In addition, a flat sealant made of EPDM was cut and prepared for the assembly. The membrane electrode assembly was manufactured as follows: a Nafion membrane with a thickness of 0.15 mm was used as the electrolyte. Platinum and carbon black were mixed using Nafion solvent and applied at a concentration of 0.4 mg / cm² to either the cathode or anode side. 2 and 0.04 mg / cm 2 The loading amount was sprayed onto both sides of the membrane. All layers were assembled on top of each other in the following order: graphite plate, gasket, structure-1, membrane electrode assembly, structure-2, gasket, and graphite plate. At a temperature of approximately 75°C, with a stable voltage of 0.6 V and 1.6 A / cm², [the membrane was subjected to a specific coating]. 2 The current density was successfully used to test the component.

[0066] List of reference numerals

[0067] 1. Fuel Cell

[0068] 2. Membrane

[0069] 3 Anode electrode layer

[0070] 4. Cathode electrode layer

[0071] 5. Gas diffusion layer

[0072] 6 First Flow Field Structure

[0073] 60 partition

[0074] 61 Allocation Channel

[0075] 62 Flow Field Channel

[0076] 620-channel structure

[0077] 63 parts

[0078] 7 Second Flow Field Structure

[0079] 70 partitions

[0080] 71 Distribution Channel

[0081] 72 Flow Field Channel

[0082] 720-channel structure

[0083] 73 parts

[0084] 730 holes

[0085] 731 Slit

[0086] 90 Fuel Manifold

[0087] 91 Oxidizing manifold

[0088] 92 Coolant manifold

[0089] A Active Region

Claims

1. A fluid guiding assembly for a fuel cell, the fluid guiding assembly comprising a channel structure (620; 720) and a gas diffusion layer (5) formed on the channel structure (620; 720), the channel structure (620; 720) defining a flow field channel (62; 72) extending from a first end of the channel structure (620; 720) to an opposite second end, wherein, Both ends of the channel structure (620; 720) are provided with porous distribution members (63; 73) extending over the entire width of the channel structure (620; 720), wherein the height of the distribution member (63; 73) is equal to the sum of the height of the gas diffusion layer (5) and the height of the channel structure (620; 720).

2. The fluid guiding assembly according to claim 1, wherein, The distribution element (63; 73) is formed as a single piece and has a porosity between 10% and 90%.

3. The fluid guiding assembly according to claim 2, wherein, The porosity varies across the width of the distribution members (63; 73).

4. The fluid guiding assembly according to claim 1 or 2, wherein, The length of the distribution component (63; 73) is in the range of 1% to 10% of the length of the flow field channel (62; 72).

5. The fluid guiding assembly according to claim 4, wherein, The length of the distribution piece (63; 73) is in the range of 0.1 mm to 20 mm.

6. The fluid guiding assembly according to claim 1 or 2, wherein, The height of the distribution components (63; 73) is in the range of 50 micrometers to 400 micrometers.

7. The fluid guiding assembly according to claim 1 or 2, wherein, The channel structure (620; 720) and the distribution element (63; 73) are permanently connected to each other.

8. The fluid guiding assembly according to claim 7, wherein, The gas diffusion layer (5), the channel structure (620; 720), and the distribution element (63; 73) are permanently connected to each other.

9. The fluid guiding assembly according to claim 1 or 2, wherein, The dispensing component (63; 73) includes at least one of the group consisting of open-cell foam, a hole pattern (730), and a slit pattern (731).

10. The fluid guiding assembly of claim 9, wherein, The dispensing element (63; 73) includes a circular, elliptical, or angled hole (730).

11. The fluid guiding assembly of claim 9, wherein, The dispensing element (63; 73) includes a straight, curved, or angled slit (731).

12. The fluid guiding assembly according to claim 1 or 2, wherein, The dispensing components (63; 73) are made of metal, plastic or resin.

13. The fluid guiding assembly according to claim 1 or 2, wherein, The channel structure (620; 720) includes straight, serpentine, or intersecting flow field channels (62; 72).

14. The fluid guiding assembly of claim 7, wherein, The channel structure (620; 720) and the distribution component are integrated into a single unit.

15. A flow field structure (6; 7) comprising a fluid guiding assembly according to claim 1 or 2 and a partition (60; 70) having a recess for receiving the fluid guiding assembly, the flow field structure further comprising a manifold (90; 91) and a distribution channel (61; 71) for supplying gas to the distributor (63; 73) at a first end of the channel structure (620; 720) and collecting gas from the distributor (63; 73) at a second end of the channel structure (620; 720).

16. A fuel cell (1) comprising at least one membrane electrode assembly (2, 3) supported by two flow field structures (6; 7) according to claim 15.

17. The fuel cell (1) according to claim 16, wherein the fuel cell comprises two current collectors and two backplates, wherein, A collector plate is arranged adjacent to each flow field structure (6; 7), and a back plate is arranged adjacent to each collector plate.

18. A method of manufacturing a fluid guiding assembly, the method comprising the steps of: - Provides channel structures (620; 720); - Perforated distribution members (63; 73) are provided at both ends of the channel structure (620; 720); as well as - A gas diffusion layer (5) is formed on the channel structure (620; 720). The height of the distribution component (63; 73) is equal to the sum of the height of the gas diffusion layer (5) and the height of the channel structure (620; 720).

19. The method of claim 18, wherein the method comprises the following steps: - Permanently connect the channel structure (620; 720) to the two distribution pieces (63; 73).

20. The method of claim 19, wherein the method comprises the following steps: At the same time or after connecting the channel structure (620; 720) and the distribution member (63; 73), - Permanently connect the gas diffusion layer (5) to the channel structure (620; 720) and the two distribution elements (63; 73).

21. The method according to claim 19 or 20, wherein, The permanent connection includes pressing, or wherein, The permanent connection includes heating and pressing.

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