Membrane sealing assembly, fuel cell, electrolytic cell and membrane assembly

Abstract

According to the present invention, there is provided a membrane seal assembly, a fuel cell, an electrolytic cell, and a membrane assembly, the membrane seal assembly being suitable for use with a flow field plate of the type comprising an inlet port, an outlet port, and a flow field for providing at least one passage between the inlet port and the outlet port. The flow field includes an inlet region, an outlet region, and a main region between the inlet region and the outlet region. The membrane seal assembly includes: an inner region including an ion conductive membrane; and a boundary region surrounding the inner region. The boundary region includes a sealing member region and at least one reinforcement region, where the sealing member region includes an ion non-conductive sealing member, and where the reinforcement region includes a reinforcement member. The at least one reinforcement region is positioned to extend at least partially across an inlet region and / or an outlet region of a flow field of the flow field plate in use, and wherein the reinforcement region has a stiffness greater than a stiffness of the sealing member region.

Description

Technical Field

[0001] This invention relates to a membrane module, specifically a membrane sealing module. The invention also relates to methods for manufacturing the membrane sealing module, and to electrochemical devices including the membrane sealing module, such as fuel cells and electrolyzers. Background Technology

[0002] A fuel cell is an electrochemical cell comprising two electrodes separated by an electrolyte. Fuel (e.g., hydrogen, alcohol (such as methanol or ethanol), or formic acid) is supplied to the anode, and an oxidant (e.g., oxygen or air) is supplied to the cathode. Electrochemical reactions occur at the electrodes, and the chemical energy of the fuel and oxidant is converted into electrical energy and heat. Electrocatalysts are used to facilitate the electrochemical oxidation of the fuel at the anode and the electrochemical reduction of oxygen at the cathode.

[0003] Fuel cells are typically classified according to the properties of the electrolyte used. The electrolyte is usually a solid polymer membrane that is electrically insulating but ionicly conductive. In a proton exchange membrane fuel cell, this ionicly conductive membrane is proton-conducting, and protons generated at the anode are transported across this membrane to the cathode, where they combine with oxygen to form water.

[0004] The main component of a proton exchange membrane fuel cell is a five-layer structure conventionally called a membrane electrode assembly. The middle layer is a polymer ion-conducting membrane. A catalyst layer, containing an electrocatalyst designed for a specific electrolysis reaction, is located on either side of the ion-conducting membrane. The catalyst layer typically also includes a proton-conducting material, such as a proton-conducting polymer, to facilitate the transfer of protons from the anode electrocatalyst to the ion-conducting membrane and / or from the ion-conducting membrane to the cathode electrocatalyst. A gas diffusion layer is located adjacent to each catalyst layer. The gas diffusion layer must allow reactants to reach the catalyst layer and must conduct the current generated by the electrochemical reaction. Therefore, the gas diffusion layer must be porous and conductive. This five-layer structure is conventionally referred to as a membrane electrode assembly.

[0005] The main components of a water electrolyzer are layered structures, also known as membrane electrode assemblies. The central layer is a polymer ion-conducting membrane, which can be either a proton-conducting or anion-conducting membrane. A catalyst layer, containing an electrocatalyst designed for a specific electrolysis reaction, is located on either side of the ion-conducting membrane. The catalyst layer typically also includes ion-conducting materials, such as proton-conducting polymers (for proton exchange membrane water electrolyzers), to facilitate ion transfer across the ion-conducting membrane between the anolyte and catholyte electrocatalysts. Adjacent to each catalyst layer is a porous transport layer (PTL) or gas diffusion layer. These layers must allow reactants to reach the catalyst layers and must conduct the current required for the electrochemical reaction. Therefore, these layers must be porous and conductive.

[0006] Conventionally, membrane electrode assemblies (MEAs) in both fuel cells and water electrolyzers are configured such that the central polymer ion-conducting membrane extends to the edge of the MEA assembly. The areas of the gas diffusion layer (or porous transport layer) and the catalyst layer are smaller than the area of ​​the polymer ion-conducting membrane, resulting in a region surrounding the MEA assembly consisting only of the ion-conducting membrane. The region lacking the catalyst layer is the non-electrochemically active region.

[0007] Individual membrane layers, such as sealing layers and sub-gaskets, formed from nonionic conductive polymers, are typically positioned at the edge regions of the membrane electrode assembly on the exposed surface of the ion-conductive membrane, where no catalyst layer exists (and which typically overlaps with the edge of the catalyst layer). These membrane layers provide a seal to prevent the escape of reactant and product gases, reinforce and strengthen the edges of the membrane electrode assembly, and provide suitable surfaces to support subsequent components, such as sub-gaskets or elastic gaskets. An adhesive layer may be present on one or both surfaces of the sealing membrane layers. This configuration, including the sealing layer, is called a membrane seal assembly, and if a sub-gasket is also present, the configuration is called a sub-gasket membrane seal assembly.

[0008] Conventionally, a (sub-gasket) membrane sealing assembly is sandwiched between two flow field plates, such as two bipolar plates. Each flow field plate allows reactants to reach a corresponding adjacent gas diffusion layer (or porous transport layer) and conducts the current generated (or desired) by the electrochemical reaction occurring at the electrodes. A bipolar plate typically includes a first surface, a second surface opposite the first surface, an inlet port, and an outlet port. Each of the first and second surfaces typically includes a flow field comprising multiple channels for conveying reactants from the inlet port to the gas diffusion layer (or porous transport layer) and for conveying reaction products (e.g., water) to the outlet port. The bipolar plate may further include a cooling channel disposed between the first and second surfaces.

[0009] The sealing material of the membrane seal assembly must be appropriately flexible to provide a sufficient seal with the flow field plates. However, when the membrane seal assembly is positioned between two flow field plates, one flow field plate may undesirably press the edge region of the membrane seal assembly into the channels of the flow field of the opposing flow field plate. This can restrict flow through the flow field and lead to non-uniform distribution of reactants (e.g., gases) in the flow field. This phenomenon is called tenting. Figure 9 A cross-sectional view of the bulge is shown, in which the seal 900 is deformed into the channel 910 of the flow field plate 920.

[0010] To mitigate the bulging effect, it is known to process recesses in a portion of the flow field of a flow field plate and attach complementary bridging members to the recesses. Figure 10A cross-sectional view is shown of a bridging member 1000 extending from a channel 1010 positioned in a recess 1020 across a flow field plate 1030. Machining suitable components in this manner can be expensive, difficult to process, and not ideal for mass production. Summary of the Invention

[0011] This invention seeks to address the aforementioned problems, expectations, and needs. Specifically, this invention provides a membrane sealing assembly (and sub-gasket membrane electrode assembly) that reduces or eliminates bulging effects and is suitable for industrial-scale manufacturing.

[0012] According to a first aspect of the invention, a membrane sealing assembly is provided, which is suitable for use with a flow field plate of the type comprising an inlet port, an outlet port, and a flow field for providing at least one passage between the inlet port and the outlet port, the flow field comprising an inlet region, an outlet region, and a main region located between the inlet region and the outlet region.

[0013] The membrane sealing assembly includes:

[0014] An internal region, comprising an ion-conducting film; and

[0015] A boundary region surrounding an inner region, the boundary region including a sealing component region and at least one reinforcing region, wherein the sealing component region includes an ion-nonconductive sealing component, and wherein the reinforcing region includes a reinforcing component;

[0016] At least one of the reinforcement regions is positioned to extend at least partially across the inlet and / or outlet regions of the flow field of the flow field plate during use, and

[0017] The reinforced area has a stiffness greater than that of the sealing component area.

[0018] Stiffness (N / m) can be calculated as the quotient of the applied force and the displacement produced in the direction of the force.

[0019] The reinforced area may include a sealing component. The reinforcing component may be positioned on the sealing component. Where the ion-conductive membrane extends into the boundary region, the reinforcing component may be directly disposed on the ion-conductive membrane.

[0020] At least one reinforcing region may have a cross-sectional thickness greater than that of the sealing member region. Typically, the cross-sectional thickness is the thickness in the direction through the plane. The reinforcing member may have a cross-sectional thickness greater than that of the sealing member in the direction through the plane. At least one reinforcing region may protrude from the sealing member region in the direction through the plane. For example, the reinforcing member may protrude from the sealing member region of the sealing member. The distance by which the reinforcing region (or reinforcing member) protrudes from the sealing member region (or sealing member) is in the range of 0 mm to 3 mm (i.e., less than 3 mm) and includes this range, preferably in the range of 10 µm to 2 mm and includes this range, and more preferably in the range of 100 µm to 1 mm and includes this range. This distance may be within the range defined by any combination of the above-described upper and lower limits.

[0021] The reinforcing and sealing components can be made of the same material, provided that the reinforcing area is harder than the sealing area (e.g., due to its greater thickness). Alternatively, the reinforcing and sealing components can be made of different materials.

[0022] The reinforced area may have a cross-sectional thickness that is substantially the same as the cross-sectional thickness of the sealing component area. Typically, the cross-sectional thickness is the cross-sectional thickness in the direction through the plane.

[0023] At least one reinforced area may be flush with the sealing component area.

[0024] The sealing components and reinforcing components in the sealing component area can be positioned in the same plane.

[0025] The reinforcing component may contain polymer materials. The polymer materials for the reinforcing component may be selected from: polyaryletherketone (PAEK), polyester, polyazoles such as polybenzimidazole (PBI), silicone, fluorosilicone, polyurethane, copolyamide, epoxy resin and fluoroacrylate.

[0026] The reinforcing component may have a Shore A hardness greater than that of the sealing component.

[0027] The reinforcing component may have a Young's modulus greater than that of the sealing component.

[0028] At least one reinforcement region may be positioned to extend across the inlet and / or outlet regions of the flow field that are completely across the flow field plate when in use.

[0029] The membrane sealing assembly may further include a first surface and a second surface, wherein at least one reinforcing region includes two or more reinforcing regions disposed on the first surface and / or the second surface. For example, the first surface may include two or more reinforcing regions. At least one reinforcing region may include a reinforcing region disposed on the first surface and a reinforcing region disposed on the second surface. That is, the first surface may include at least one reinforcing region, and the second surface may include at least one reinforcing region. Each reinforcing region suitably includes a reinforcing member.

[0030] The flow field plate can be of the type in which the inlet and / or outlet regions independently include recessed portions extending at least partially (or completely) across the passage, and in which reinforcing members of at least one reinforcing region are positioned to be received by the recessed portions of the inlet and / or outlet regions of the flow field plate. For example, the inlet region may include a recessed portion, and at least one reinforcing region may include a reinforcing member positioned to be received by the recessed portion of the inlet region. As another example, the outlet region may include a recessed portion, and at least one reinforcing region may include a reinforcing member positioned to be received by the recessed portion of the outlet region. The inlet and outlet regions may each include a recessed portion, and at least one reinforcing region may include a reinforcing member positioned to be received by the recessed portion of the inlet region and (additionally) a reinforcing member positioned to be received by the recessed portion of the outlet region.

[0031] The ion-conducting film can extend into the boundary region. For example, the boundary region may include an inner boundary region (or overlapping region) and an outer boundary region surrounding the inner boundary region. The inner boundary region may include the ion-conducting film and a sealing element. Suitably, the inner boundary region does not include a reinforcing region. The outer boundary region does not have an ion-conducting film and suitably includes a sealing element and a reinforcing region.

[0032] The ion-conducting film may include planar reinforcement members. These planar reinforcement members may be embedded within the ion-conducting film. The planar reinforcement members may extend into the boundary region.

[0033] The internal region may further include at least one catalyst layer on the ion-conducting membrane. A first catalyst layer may be disposed on a first surface of the ion-conducting membrane. A second catalyst layer may be disposed on a second surface of the ion-conducting membrane. The membrane sealing assembly may be a catalyzed membrane sealing assembly.

[0034] The membrane sealing assembly may further include a gas diffusion layer (or porous transport layer) disposed on a catalyst layer on a first and / or second surface of the ion-conducting membrane.

[0035] According to a second aspect, a membrane seal assembly according to the first aspect is provided, the membrane seal assembly being combined with a flow field plate including an inlet port, an outlet port, and a flow field for providing at least one passage between the inlet port and the outlet port, the flow field including an inlet region, an outlet region, and a main region between the inlet region and the outlet region. At least one reinforcement region is positioned to extend at least partially (or completely) across the inlet region and / or the outlet region of the flow field. The flow field plate may be a bipolar plate.

[0036] Membrane seal assemblies and flow field plates can be arranged in combination in a stack. For example, a membrane seal assembly can be sandwiched between two flow field plates, such as two bipolar plates.

[0037] According to another aspect, an electrochemical device, such as a fuel cell or an electrolyzer, is provided, comprising a membrane sealing assembly according to the first or second aspect. The fuel cell is preferably a proton exchange membrane fuel cell. The electrolyzer may be an anion exchange membrane water electrolyzer. The electrolyzer is preferably a proton exchange membrane water electrolyzer.

[0038] According to another aspect, a method for manufacturing a membrane sealing assembly according to the first aspect is provided. The method includes the following steps:

[0039] (a) A sealing element is provided on or around an ion-conductive membrane to define an inner region including the ion-conductive membrane and a boundary region surrounding the inner region, the boundary region including the sealing element, wherein the sealing element is ion-nonconductive;

[0040] (b) Depositing the reinforcing component precursor material onto the boundary region; and

[0041] (c) Curing the precursor material of the reinforcing member to form at least one reinforcing region including the reinforcing member.

[0042] Step (b) may include depositing reinforcing component precursor material onto the sealing component.

[0043] According to another aspect, a membrane assembly is provided that is suitable for use with a flow field plate of the type comprising an inlet port, an outlet port, and a flow field for providing at least one channel between the inlet port and the outlet port, the flow field comprising an inlet region, an outlet region, and a main region located between the inlet region and the outlet region.

[0044] The membrane assembly includes an ion-conducting membrane and a reinforcing component, wherein the ion-conducting membrane includes:

[0045] An internal region, which is used to align with the main region of the flow field during application; and

[0046] A boundary region that surrounds the interior region and is used to align with the inlet and / or outlet regions of the flow field during application.

[0047] The boundary area includes at least one reinforced region, and the at least one reinforced region includes a reinforcing component.

[0048] At least one of the reinforcing components is positioned on the ion-conductive film so that, in use, it extends at least partially across the inlet and / or outlet regions of the flow field of the flow field plate, and

[0049] The reinforced region has a stiffness greater than that of other regions in the boundary region.

[0050] Preferably, the reinforcing component has a stiffness greater than that of the ion-conducting film. Attached Figure Description

[0051] Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings, in which:

[0052] Figure 1 This is a schematic diagram of the first side of the bipolar plate;

[0053] Figure 2 This is a schematic diagram of the second side of the bipolar plate;

[0054] Figure 3 It is a cross-sectional view of multiple channels in the flow field plate;

[0055] Figure 4 This is a schematic diagram of one surface of the flow field plate, including the recessed portion;

[0056] Figure 5 This is a cross-sectional view of the recessed portion of the flow field plate;

[0057] Figure 6 This is a schematic diagram of the first side of the membrane sealing assembly;

[0058] Figure 7 This is a schematic diagram of the second side of the membrane sealing assembly;

[0059] Figure 8 This is a schematic side view of the membrane seal assembly;

[0060] Figure 9 It is a cross-sectional view of the seal in the channel deformed into the flow field plate; and

[0061] Figure 10 This is a cross-sectional view of the bridging plate extending across the flow field plate. Detailed Implementation

[0062] Preferred and / or optional features will now be described. Unless the context otherwise requires, any aspect of the invention may be combined with any other aspect of the invention. Unless the context otherwise requires, any preferred or optional feature of any aspect may be combined with any aspect of the invention, alone or in combination. For the avoidance of doubt, the same reference numerals are used in the drawings to denote the same features. The drawings are not drawn to scale.

[0063] Flow field plate

[0064] This invention provides a membrane sealing assembly suitable for use with at least one flow field plate. A suitable flow field plate is of the type including an inlet port, an outlet port, and a flow field for providing at least one passage between the inlet and outlet ports. The flow field plate may have a flow field on only one side. Alternatively, the flow field plate may have a flow field on each side thereof. The flow field plate may be a bipolar plate. This is merely an example. Figure 1 and Figure 2 A bipolar plate 100 suitable for use with the membrane sealing assembly of the present invention is shown. The bipolar plate 100 includes a first side 102 (e.g., ...). Figure 1 (as shown) and the second side 104 (as shown) Figure 2 (As shown). In this example, the bipolar plate 100 includes three inlet ports 110, 120, and 130 and three outlet ports 115, 125, and 135. In this example, each of the inlet and outlet ports is an aperture extending through the entire thickness of the bipolar plate 100.

[0065] The first inlet port 110 is fluidly connected to the first outlet port 115 via the flow field 140 on the first side 102 of the bipolar plate 100. Figure 1 The first inlet port 110 can supply reactants to the flow field 140. The first outlet port 115 can convey discharged material away from the flow field 140. For example, the first inlet port 110 can be a fuel inlet port, such as a hydrogen inlet port.

[0066] The flow field 140 includes an inlet region 142, an outlet region 144, and a main region 146 between the inlet and outlet regions. When assembled with a membrane seal assembly, the main region 146 typically corresponds substantially to the portion of the flow field directly adjacent to the electrochemically active region of the membrane seal assembly. The inlet region 142 and the outlet region 144 of the flow field 140 are typically directly adjacent to the non-ionic conductive boundary region of the membrane seal assembly. Each of the inlet region 142, the main region 146, and the outlet region 144 includes a plurality of channels for providing at least one passage through the flow field 140. The plurality of channels includes a series of alternating grooves 148 and ridges 150 (sometimes referred to as “land”). There are no particular limitations on the number and arrangement of channels in the flow field. Figure 3A cross-sectional view of an exemplary plurality of channels 300 including a series of alternating grooves 148 and ridges 150 is shown.

[0067] The first side 102 may further include a sub-gasket recess 160 for receiving a sub-gasket. The sub-gasket may help provide a suitable seal between the first side 102 of the bipolar plate 100 and the membrane sealing assembly.

[0068] The second inlet port 120 is fluidly connected to the second outlet port 125 via the flow field 140' on the second side 104 of the bipolar plate 100. Figure 2 The second inlet port 120 can supply reactants to the flow field 140'. The second outlet port 125 can convey discharged material away from the flow field 140'. The second inlet port 120 can be an oxidant inlet port, such as an air or oxygen inlet port.

[0069] The flow field 140' includes an inlet region 142', an outlet region 144', and a main region 146' between the inlet and outlet regions. Each of the inlet region 142', the main region 146', and the outlet region 144' includes a plurality of channels for providing at least one passage through the flow field 140'. The plurality of channels includes a series of alternating grooves 148' and ridges 150'. There are no particular limitations on the number and arrangement of the channels in the flow field.

[0070] The second side 104 may further include a sub-gasket recess 160' for receiving a sub-gasket. The sub-gasket can help provide a suitable seal between the second side 104 of the bipolar plate 100 and another membrane sealing assembly.

[0071] The third inlet port 130 and the third outlet port 135 are optional. If present, the third inlet port 130 is in fluid communication with the third outlet port 135 via an internal channel (not shown). The internal channel may be located between the first side 102 and the second side 104. Preferably, the third inlet port 130 is a coolant inlet port for supplying coolant to the internal channel, which can serve as a cooling channel.

[0072] For the sake of brevity, the following description refers only to the first side 102 of the bipolar plate. However, the same features may also exist independently on the second side 104 of the bipolar plate.

[0073] Figure 4 Another example of a bipolar plate 400 suitable for use with the membrane sealing assembly of the present invention is shown. Optionally, at least one (and preferably both) of the inlet region 142 and / or outlet region 144 of the flow field 140 includes a recessed portion 170. The recessed portion 170 is formed by... Figure 4The area defined by the dotted line in the diagram. The recessed portion 170 extends laterally across the passageways provided by the multiple channels of the entrance area 142 and / or the exit area 144.

[0074] Figure 5 A schematic cross-sectional view of the recessed portion 170 is shown. The recessed portion 170 includes a plurality of channels for providing at least one passage through the flow field 140. The plurality of channels include a series of alternating grooves 148 and ridges 152. The bottoms of the grooves 148 are generally located in the same plane (i.e., the bottom of the groove plane P1). Typically, the (non-recessed) main region 146 includes a ridge 150 forming a main ridge plane P2. Typically, the recessed portion 170 includes a ridge 152 forming a recessed ridge plane P3. The recessed ridge plane P3 is positioned between the bottom of the groove plane P1 and the main ridge plane P2. The distance between the ridge of the main portion 150 (i.e., the main ridge plane P2) and the ridge of the recessed portion 152 (i.e., the recessed ridge plane P3) (through the plane) defines the depth of the recess. d That is, the recessed portion 170 is recessed from the main area 146 to the depth of the recessed portion. d The depth of the recess can range from 0 mm to approximately 1 mm, and includes 0 mm to approximately 1 mm. A recess depth within this range can help maintain an acceptable fluid flow rate and an acceptable pressure drop through the channel. An excessively large recess depth can impair fluid flow through the channel and result in a large pressure drop.

[0075] Membrane sealing assembly

[0076] Figure 6 and Figure 7 An exemplary embodiment of the membrane sealing assembly 600 of the present invention is shown. The membrane sealing assembly 600 has a first surface 602 (e.g., Figure 6 (as shown) and the second side 604 (as shown) Figure 7 (As shown).

[0077] The membrane sealing assembly 600 includes an inner region 606 and a boundary region 608 surrounding the inner region 606.

[0078] The internal area refers to the area within xy A planar region in the direction (in-plane direction), and the planar region in the direction (through the plane) z (Direction) Extends through the thickness of the membrane seal assembly.

[0079] Boundary zone refers to xy A planar region in the direction (in-plane direction), and the planar region in the direction (through the plane) z The boundary region extends through the thickness of the membrane seal assembly in the direction of the membrane seal assembly, and extends around the periphery of the inner region.

[0080] The inner region 606 includes an ion-conducting film. The boundary region 608 includes a sealing member region 640 for sealing the ion-conducting film. The sealing member region 640 includes a sealing member. The sealing member is ion-nonconducting. The boundary region 608 further includes at least one reinforcing region to provide a region with greater stiffness in the boundary region, for example, compared to the sealing member region. The reinforcing region suitably includes a reinforcing member. The reinforcing region has a greater (through-plane) stiffness than other regions of the boundary region, such as the sealing member region 640.

[0081] Each or both of the first surface 602 and the second surface 604 may independently include one or more reinforcing regions. For example, at least one reinforcing region may be provided on the first surface 602, the second surface 604, or both the first surface 602 and the second surface 604. The reinforcing regions are positioned to extend at least partially (and preferably completely) across the inlet and / or outlet regions of the flow field of the flow field plate (e.g., a bipolar plate) during use (e.g., laterally or sideways across at least one passage). For example, reinforcing region 650 (located on the first surface 602) is positioned to extend across the inlet region 142 of the flow field 140 of the bipolar plate 100. Reinforcing region 652 (located on the first surface 602) is positioned to extend across the outlet region 144 of the flow field 140 of the bipolar plate 100. Similarly, reinforcing region 650' (located on the second surface 604) is positioned to extend across the inlet region 142' of the flow field 140' of the bipolar plate 100. The reinforcing region 652' (located on the second surface 604) is positioned to extend across the outlet region 144' of the flow field 140' of the bipolar plate 100. In these embodiments, the reinforcing regions 650, 652, 650', and 652' are in the form of strips or patches. The membrane sealing assembly of the present invention may include any combination of the reinforcing regions 650, 652, 650', and 652'.

[0082] Providing a reinforcing region in the boundary area of ​​the membrane seal assembly suppresses bulging effects; this reinforcing region is positioned to extend at least partially across at least one passage of the flow field during use. Additionally, incorporating the reinforcing region as an integral part of the membrane seal assembly allows the membrane seal assembly of the present invention to be used with existing commercially available flow field plates without the need to manufacture and use additional bridging components. This simplifies the manufacturing process and can reduce manufacturing costs. Therefore, the method of manufacturing the membrane seal assembly of the present invention is also more suitable for industrial-scale manufacturing.

[0083] The membrane sealing assembly may further include a first catalyst layer located on a first surface of the inner region 606 (e.g., on the first surface of the ion-conducting membrane). The membrane sealing assembly may further include a second catalyst layer located on a second surface of the inner region 606 (e.g., on the second surface of the ion-conducting membrane). The membrane sealing assembly may further include catalyst layers located on both the first and second surfaces of the inner region 606 (e.g., on both the first and second surfaces of the ion-conducting membrane). The catalyst layers on the first and / or second surfaces may overlap with or extend into the boundary region 608. The membrane sealing assembly may be a catalyzed membrane sealing assembly.

[0084] The membrane sealing assembly may further include a gas diffusion layer (or porous transport layer) located on the catalyst layer on the first and / or second surfaces. The gas diffusion layer (or porous transport layer) may overlap with the boundary region 608.

[0085] The membrane sealing assembly (or, depending on the circumstances, the membrane assembly) is preferably a rolled product. Therefore, the membrane sealing assembly (or membrane assembly) can be wound into rolls suitable for storage and transfer.

[0086] Internal area

[0087] The inner region is suitably defined by the inner periphery of a sealing element and optional reinforcing elements. In use, the inner region can be substantially aligned with or overlap with the main region of the flow field of the flow field plate. Typically, the inner region is the ion-conducting region of the membrane sealing assembly, such as the proton-conducting region. The inner region includes an ion-conducting membrane. The inner region may further include planar reinforcing elements.

[0088] Ion conductive film

[0089] The ion-conducting membrane comprises an ion-conducting polymer. The ion-conducting polymer can be a proton-conducting polymer or anion-conducting polymer. Preferably, the ion-conducting polymer is a proton-conducting polymer. A preferred ion-conducting polymer is a partially or fully fluorinated sulfonic acid polymer, such as a perfluorinated sulfonic acid polymer. For example, the ion-conducting polymer may be based on a perfluorinated sulfonic acid material, such as Nafion. ® (Chemours Company), Aquivion ® (Solvay Specialty Polymers), Flemion ® (Asahi Glass Group) and Aciplex ® (Asahi Kasei Chemicals Corp.). Alternatively, ion-conducting materials may be based on sulfonated hydrocarbon polymers, such as those purchased from FuMA-Tech GmbH (using fumapem). ®Products from P, E, or K series, such as those from JSR Corporation and Toyobo Corporation.

[0090] The ion-conducting film can extend into the boundary region. For example, the boundary region may include an inner boundary region (or overlapping region) and an outer boundary region surrounding the inner boundary region. The inner boundary region may include the ion-conducting film and a sealing element. Suitably, the inner boundary region does not include a reinforcing region. The outer boundary region does not have an ion-conducting film and suitably includes a sealing element and a reinforcing region.

[0091] The ion-conducting membrane may include planar reinforcement members. These planar reinforcement members may be embedded within the ion-conducting membrane. Preferably, the planar reinforcement members are porous (i.e., include pores). The reinforcement members impart mechanical strength to the ion-conducting membrane. The reinforcement members may comprise porous reinforcing materials such as expanded polytetrafluoroethylene (ePTFE) or nanofiber networks such as networks comprising polybenzimidazole (PBI) fibers or glass fibers. The planar reinforcement members may extend into the boundary region.

[0092] Catalyst layer

[0093] A first catalyst layer is provided on one side (e.g., the first side) of a first catalyst layer film. A second catalyst layer is provided on the other side (e.g., the second side) of a second catalyst layer film. The first catalyst layer may be an anodic catalyst layer. The second catalyst layer may be a cathode catalyst layer. For example, the interior region may include the first catalyst layer (e.g., the anodic catalyst layer) located on the first side of the ion-conducting membrane. The interior region may include the second catalyst layer (e.g., the cathode catalyst layer) located on the second side of the ion-conducting membrane.

[0094] The first catalyst layer and the second catalyst layer contain an electrocatalyst. The electrocatalysts in the first catalyst layer and the second catalyst layer are preferably different. The electrocatalyst can be unsupported metal particles (e.g., finely divided unsupported metal powder) or it can be a supported electrocatalyst wherein the metal particles (e.g., nanoparticles) are dispersed on a conductive support such as a conductive particulate carbon support.

[0095] The metal particles of the electrocatalyst are appropriately selected from:

[0096] (i) Platinum group metals (i.e., platinum, palladium, rhodium, ruthenium, iridium and osmium).

[0097] (ii) Gold or silver,

[0098] (iii) Base metals, or

[0099] (iv) An alloy or mixture comprising one or more of these metals or their oxides. Preferably, the metal in the metal particles of the electrocatalyst is a platinum group metal or an alloy of platinum group metals. The most preferred electrocatalyst metal is platinum, which can form alloys with other noble or base metals. The base metal is tin or a transition metal that is not a noble metal. The noble metal is a platinum group metal (platinum, palladium, rhodium, ruthenium, iridium, or osmium), silver, or gold. Preferred base metals are copper, cobalt, nickel, zinc, iron, titanium, molybdenum, vanadium, manganese, niobium, tantalum, chromium, and tin.

[0100] Gas diffusion layer

[0101] The internal region may further include a gas diffusion layer disposed on the catalyst layer. For example, a first gas diffusion layer may be disposed adjacent to the first catalyst layer. A second gas diffusion layer may be disposed adjacent to the second catalyst layer.

[0102] The gas diffusion layer may overlap with a portion of the boundary region.

[0103] For water electrolyzer applications, the internal region may further include a porous transport layer disposed on the catalyst layer. For example, a gas diffusion layer may be disposed adjacent to the first catalyst layer, and the porous transport layer may be disposed adjacent to the second catalyst layer. The porous transport layer may overlap with a portion of the boundary region.

[0104] Boundary area

[0105] A boundary region surrounds the inner region. The boundary region suitably includes a sealing component region and a reinforcing region. The sealing component region includes a sealing component. The reinforcing region suitably includes a reinforcing component. The inner periphery of the sealing component and optionally at least one reinforcing component may define the inner region. When in use, the boundary region may surround the main region of the flow field of the flow field plate. When in use, the boundary region may be aligned with the inlet and / or outlet regions of the flow field of the flow field plate. When in use, the boundary region suitably covers the inlet and outlet regions of the flow field of the flow field plate. The boundary region is suitably ionically non-conductive.

[0106] The ion-conductive film may extend at least partially into the boundary region, for example, below the sealing member or between two sealing members disposed on either side of the ion-conductive film. In such embodiments, the boundary region may include an inner boundary region (or overlapping region) and an outer boundary region surrounding the inner boundary region. The inner boundary region may include the ion-conductive film and the sealing member. Preferably, the inner boundary region does not include a reinforcing region. The outer boundary region does not have an ion-conductive film and preferably includes the sealing member and the reinforcing region. Preferably, the sealing member region in the outer boundary region is substantially planar. Preferably, the sealing member region in the outer boundary region has a substantially uniform thickness.

[0107] The boundary region (and preferably the outer boundary region) may include one or more port holes positioned to complement the inlet port (i.e., inlet port hole) and outlet port (i.e., outlet port hole) of the flow field plate. For example, when used with bipolar plate 100, holes 610, 620, and 630 may be positioned to align with inlet ports 110, 120, and 130, respectively. Similarly, when used with bipolar plate 100, holes 615, 625, and 635 may be positioned to align with outlet ports 115, 125, and 135, respectively.

[0108] Sealing component area

[0109] The sealing component region appropriately forms a framework surrounding the inner region. The sealing component region appropriately forms a framework surrounding the ion-conducting membrane of the inner region. The sealing component may be positioned on the peripheral portion of the ion-conducting membrane such that the ion-conducting membrane overlaps with the sealing component. In other embodiments, the sealing component may be positioned around the edge of the ion-conducting membrane without overlap. When a catalyst layer is present on at least one surface of the ion-conducting membrane, the sealing component may overlap with the catalyst layer. In other embodiments, the sealing component does not overlap with the catalyst layer.

[0110] The sealing component includes a sealing material. The sealing material is suitably a polymer material, and preferably an elastomer. The sealing material can be selected from the group consisting of: silicones, fluorosilicones, polyurethanes, copolyamides, polyazoles, epoxy resins, and fluoroacrylates. Specific examples of suitable sealing materials include: polyvinylidene fluoride (PVDF), polyetherimide (PEI), polyimide (PI), polyethersulfone (PES), fluorinated ethylene propylene (FEP), ethylene tetrafluoroethylene (ETFE), and Viton. ® Polyethylene oxide (PEO), polyphenylene oxide (PPE), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyacrylonitrile (PAN), polyphenylene sulfide (PPS), polybenzimidazole (PBI), polyolefins, and silicones.

[0111] The sealing component suitably has a Young's modulus of less than 3 GPa, preferably less than 2.5 GPa, and more preferably less than 2 GPa. The sealing component suitably has a Young's modulus of at least 200 MPa. When the Young's modulus is too high, the sealing component cannot form a suitable fluid-impermeable seal. The Young's modulus can be obtained using a Houndsfield tensile meter with the measurement method defined in ASTM E111–17.

[0112] Preferably, the membrane sealing assembly includes a sealing element on each of its first and second surfaces.

[0113] When in use, the sealing element can be configured to provide a seal around the inlet and / or outlet ports of the flow field plate. For example, the edge of the port orifice preferably includes the sealing element.

[0114] Strengthen the region

[0115] For example, a reinforced region provides a higher stiffness zone in the boundary region compared to the sealing region. Stiffness (N / m) can be calculated as the quotient of the applied force and the displacement produced in the direction of the force. Stiffness can be determined using standard test methods as defined in ASTM D1043-16.

[0116] When assembled with a flow field plate (i.e., when in use), the reinforcement region is positioned in the boundary region to extend at least partially (and preferably completely) across the inlet and / or outlet regions of the flow field of the flow field plate. In use, the reinforcement region is suitably positioned to extend across at least one passageway in the inlet and / or outlet regions of the flow field (e.g., laterally or laterally across multiple channels providing at least one passageway). The reinforcement region may be positioned adjacent to at least one port hole present in the boundary region. Preferably, the reinforcement region is adjacent to and spaced apart from the edge of at least one port hole present in the boundary region, such that the edge of the port hole is composed of sealing material from the sealing member region. Preferably, the reinforcement region is disposed adjacent to at least one port hole present in the boundary region and is positioned between at least one port hole and the inner region, preferably in the form of a patch or strip. Preferably, the reinforcement region is adjacent to at least one port hole and extends across the full dimension (e.g., width or length) of the port hole.

[0117] The added stiffness in this region prevents the boundary region from deforming into multiple channels in the flow field. That is, it can suppress bulging. At the same time, the bulk properties of the boundary region (e.g., sealing components) are not substantially affected, so that a sufficiently impermeable seal can still be provided.

[0118] The reinforced region appropriately includes reinforcing members. The reinforcing members provide increased stiffness to the boundary areas within the reinforced region. Preferably, the reinforcing members are exposed on the surface of the reinforced region. When assembled with the flow field plate (i.e., when in use), the reinforcing members can directly contact the flow field plate.

[0119] The reinforced area may further include a sealing element. The reinforcing element may be disposed on the sealing element, for example as an additional component of the sealing element.

[0120] The reinforcing region may have a cross-sectional thickness greater than that of the sealing region. The greater thickness of the reinforcing region compared to the sealing region provides a region with greater stiffness or rigidity. In this embodiment, the reinforcing member and the sealing member may be made of the same material, for example, as a single piece. Alternatively, the reinforcing member and the sealing member may be made of different materials. For example, the reinforcing member may be made of a material that is inherently more rigid or harder than the sealing member.

[0121] The reinforcing member can be disposed in the same plane as the sealing member. For example, the reinforcing member can be embedded within the sealing member.

[0122] The sealing component may surround the reinforcing component (in the same plane).

[0123] The reinforcing region may have a cross-sectional thickness substantially the same as that of the sealing region (through the plane). The reinforcing region may be flush with the sealing region (i.e., have the same cross-sectional thickness at the boundary between the sealing region and the reinforcing region).

[0124] Providing reinforcing components as additional or integral parts of the boundary region of the membrane electrode assembly can reduce the complexity of building fuel cell stacks and increase the versatility of manufacturing designs, enabling faster and more cost-effective manufacturing processes.

[0125] The reinforcing element is suitably ionically non-conductive. The reinforcing element is not an ionically conductive membrane. The reinforcing element is not a sub-gasket used to provide a fluid-impermeable seal between the membrane sealing assembly and the flow field plate.

[0126] Preferably, the sealing materials of the reinforcing component and the sealing component are suitably different in the sense that they have different chemical compositions. In other words, they are preferably different chemical substances. The reinforcing component is preferably made of a polymeric material. Suitable polymeric materials can be selected from the group consisting of: polyaryletherketone (PAEK), polyester, polyazole, silicone, fluorosilicone, polyurethane, copolyamide, epoxy resin, and fluoroacrylate. Specific examples of suitable materials for the reinforcing component include: polyetheretherketone (PEEK), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), polyvinylidene fluoride (PVDF), polyetherimide (PEI), polyimide (PI), polyethersulfone (PES), fluorinated ethylene propylene (FEP), ethylene-tetrafluoroethylene (ETFE), and Viton ® Polyethylene oxide (PEO), polyphenylene oxide (PPE), polyacrylonitrile (PAN), polyphenylene sulfide (PPS), polybenzimidazole (PBI), polyolefins, and silicones.

[0127] Preferably, the reinforcing component can be formed by curing a printable reinforcing component precursor material.

[0128] Preferably, the reinforcing member is made of a material that is more rigid than the sealing member. The reinforcing member appropriately has a Young's modulus greater than that of the sealing member.

[0129] Stiffness can be measured using the standard test methods defined in ASTM D1043-16.

[0130] When the flow field plate is of the type including recessed portions, the reinforcing member can be configured to be received by the recessed portion of the flow field in the inlet and / or outlet regions of the flow field of the flow field plate. For example, the reinforcing member 650 can be configured to be complementary to the recessed portion 170 of the inlet region 142. Figure 4 and Figure 6 Independently, the reinforcing member 652 may be configured to complement the recessed portion 170 of the outlet region 144. As another example, in the case where the flow field plate is of the type in which each of the inlet and outlet regions includes a recessed portion extending laterally across a passage provided by a plurality of channels, at least one reinforcing member may include a (first) reinforcing member positioned to be received by the recessed portion of the inlet region and a (second) reinforcing member positioned to be received by the recessed portion of the outlet region.

[0131] Specifically, in the case where the flow field plate is of the type including a recessed portion 170, the reinforcing member can (in the penetrating plane ( z (in the direction) protrudes from the layer of the sealing component. Figure 8 A schematic side view of the membrane seal assembly 600 is shown, in which reinforcing members 650, 652, 650', and 652' protrude from the seal member 640 in a through-plane direction. The reinforcing members 650, 652, 650', and 652' are in the form of elongated strips or patches. The reinforcing members can protrude from the seal member by a distance complementary to the distance by which the recessed portion is recessed from the main region. That is, the depth of the reinforcing members protruding from the seal member corresponds to the depth of the recess. d The distance is essentially the same. In some implementations, the reinforcing member can protrude from the sealing member beyond the depth of the recess. d In such embodiments, the reinforcing member can be compressed to form a fluid-impermeable seal. The reinforcing member can protrude from the sealing member so as to extend beyond the gas diffusion layer (or porous delivery layer) (if present).

[0132] The reinforcing member may protrude from the sealing member by a distance ranging from 0 mm to 3 mm, preferably from 10 µm to 2 mm, and most preferably from 100 µm to 1 mm. A larger protrusion distance can provide a more rigid reinforcing member and thus further reduce the degree to which the sealing member deforms into the flow field channels, but may impair fluid flow rate.

[0133] Preferably, the membrane seal assembly includes at least two reinforcing regions. Each reinforcing region may include a reinforcing member. For example, the reinforcing member can be disposed on a first and / or second surface of the membrane seal assembly in any combination. At least one reinforcing region may include two or more reinforcing regions disposed on the first surface. For example, one surface of the membrane seal assembly may include a first reinforcing region including a reinforcing member positioned to extend at least partially across the inlet region of the flow field of the flow field plate; and a second reinforcing region including a reinforcing member positioned to extend at least partially across the outlet region of the flow field of the flow field plate. As another example, when the flow field plate is of the type including a flow field having a recessed inlet region and a recessed outlet region, one surface of the membrane seal assembly may include a first reinforcing region and a second reinforcing region, the first reinforcing region including a reinforcing member configured to be received by a recess in the inlet region, and the second reinforcing region including a reinforcing member configured to be received by a recess in the outlet region.

[0134] At least one reinforcing region may include a first reinforcing region and another reinforcing region, the first reinforcing region including a reinforcing member disposed on a first surface, and the other reinforcing region including a reinforcing member disposed on a second surface. For example, in some preferred embodiments, the membrane seal assembly includes a third reinforcing region and an optional fourth reinforcing region disposed in the boundary region of the membrane seal assembly on the surface opposite to the first reinforcing region and (if present) the second reinforcing region. In this embodiment, the third and fourth reinforcing regions each include reinforcing members positioned to extend at least partially across the inlet and outlet regions of the flow field of the second flow field plate, respectively.

[0135] The membrane seal assembly may include any combination of a first reinforcing region, a second reinforcing region, a third reinforcing region, and a fourth reinforcing region, which include reinforcing members positioned to extend across the inlet and / or outlet regions of the flow field of a bipolar plate disposed on either side of the membrane seal assembly.

[0136] In some embodiments, the ion-conducting film extends into the boundary region, and the reinforcing member is disposed directly on the ion-conducting film (i.e., there is no sealing member). The reinforcing member provides a region with higher stiffness in the boundary region compared to other areas of the ion-conducting film. A sealing member can be appropriately added in subsequent manufacturing steps.

[0137] Manufacturing method

[0138] This invention provides a method for preparing a membrane sealing assembly. The method includes the following steps:

[0139] (a) A sealing element is provided on or around an ion-conductive membrane to define an inner region including the ion-conductive membrane and a boundary region surrounding the inner region, the boundary region including a sealing element region, wherein the sealing element region includes the sealing element and the sealing element is ion-nonconductive;

[0140] (b) Depositing the reinforcing component precursor material onto the boundary region; and

[0141] (c) Curing the precursor material of the reinforcing member to form at least one reinforcing region including the reinforcing member.

[0142] In some implementations, step (a) is performed before step (b). In other implementations, step (a) is performed after step (b) or (c).

[0143] When in use, the reinforcing component precursor material is deposited such that it is positioned to extend at least partially across the inlet and / or outlet regions of the flow field of the flow field plate. The reinforcing region has a stiffness greater than that of the sealing component region.

[0144] Step (a)

[0145] The step of providing a sealing component may include the following sub-steps:

[0146] Depositing the sealing component precursor material onto or around an ion-conductive film; and

[0147] Precursor material for cured sealing components.

[0148] Precursor materials for sealing components can be deposited using printing techniques such as inkjet printing, dispersion jet printing, screen printing, pad coating, aerosol jet printing, and gravure coating (e.g., digital printing).

[0149] Suitable, the sealing component precursor is a curable material. The steps of curing the sealing component precursor material may include photocuring (e.g., exposing the sealing component precursor material to visible or ultraviolet light) or thermocuring.

[0150] Alternatively, the step of providing the sealing component may include positioning the pre-formed sealing component (e.g., as a frame) on and around the ion-conductive membrane.

[0151] The ion-conducting membrane may contain a catalyst layer on one or both sides. The ion-conducting membrane may also contain a gas diffusion layer (or porous transport layer) on one or both sides. In some embodiments, the catalyst layer may be added after steps (a), (b), or (c). In some embodiments, the gas diffusion layer (or porous transport layer) may be added after the catalyst layer.

[0152] Steps (b) and (c)

[0153] Step (b) may include printing (e.g., digital printing) the reinforcing component precursor material onto the boundary area. Suitable printing techniques include inkjet printing, dispersion jet printing, screen printing, pad coating, aerosol jet printing, and gravure coating.

[0154] Suitable, the reinforcing component precursor is a curable material. The steps of curing the reinforcing component precursor material may include photocuring (e.g., exposing the reinforcing component precursor material to visible or ultraviolet light) or thermocuring.

[0155] The reinforcing precursor material can be deposited onto the boundary region, flush with the sealing component. Alternatively, the reinforcing precursor material can be deposited onto the boundary region, along the through-plane. z The direction protrudes from the sealing component. For example, a reinforcing component precursor material may be deposited onto the sealing component. In another embodiment, the sealing component may cover the reinforcing component.

[0156] In cases where the method includes depositing a sealing component precursor material, the sealing component precursor material and the reinforcing component precursor material can be cured simultaneously.

Claims

1. A membrane sealing assembly, said membrane sealing assembly being combined with a flow field plate including an inlet port, an outlet port, and a flow field for providing at least one passage between said inlet port and said outlet port, said flow field including an inlet region, an outlet region, and a main region located between said inlet region and said outlet region. The membrane sealing assembly includes: An internal region, the internal region including an ion-conducting film; and A boundary region surrounding the inner region, the boundary region including a sealing component region, at least one reinforcing region and at least one port hole, wherein the sealing component region includes an ion-nonconductive sealing component, and wherein the reinforcing region includes a reinforcing component; The feature is that the at least one reinforcing region is in the form of a patch or strip, the patch or strip being disposed adjacent to at least one port hole present in the boundary region and between the at least one port hole and the inner region, such that the at least one reinforcing region is positioned to extend at least partially across the inlet region and / or the outlet region of the flow field of the flow field plate, and The reinforced region has a stiffness greater than that of the sealing component region.

2. The membrane sealing assembly according to claim 1, wherein the reinforced region includes the sealing component.

3. The membrane sealing assembly according to claim 2, wherein the reinforcing member is positioned on the sealing member.

4. The membrane sealing assembly according to claim 1 or 2, wherein the at least one reinforcing region has a cross-sectional thickness greater than the cross-sectional thickness of the sealing member region.

5. The membrane sealing assembly of claim 4, wherein the reinforcing member and the sealing member are made of the same material.

6. The membrane sealing assembly according to claim 1 or 2, wherein the reinforcing member and the sealing member are made of different materials.

7. The membrane sealing assembly according to claim 1 or 2, wherein the reinforcing region has a cross-sectional thickness substantially the same as the cross-sectional thickness of the sealing component region.

8. The membrane sealing assembly according to claim 1 or 2, wherein the at least one reinforcing region is flush with the sealing component region.

9. The membrane sealing assembly according to claim 1 or 2, wherein the sealing member and the reinforcing member in the sealing member region are positioned in the same plane.

10. The membrane sealing assembly according to claim 1 or 2, wherein the reinforcing member comprises a polymer material.

11. The membrane sealing assembly according to claim 1 or 2, wherein the reinforcing member has a Shore A hardness greater than that of the sealing member.

12. The membrane sealing assembly according to claim 1 or 2, wherein the reinforcing member has a Young's modulus greater than that of the sealing member.

13. The membrane sealing assembly according to claim 1 or 2, wherein the at least one reinforcing region is positioned to extend completely across the inlet and / or outlet regions of the flow field of the flow field plate.

14. The membrane sealing assembly of claim 1, wherein the reinforcing region is positioned between the at least one port orifice and the inner region so as to extend at least partially across the cross-sectional dimension of the port orifice.

15. The membrane sealing assembly of claim 1, wherein the reinforcing region is positioned between the at least one port orifice and the inner region to extend completely across the cross-sectional dimension of the port orifice.

16. The membrane sealing assembly of claim 1, further comprising a first surface and a second surface, wherein the at least one reinforcing region comprises two or more reinforcing regions disposed on the first surface and / or the second surface.

17. The membrane sealing assembly of claim 16, wherein the first surface comprises two or more reinforcing regions.

18. The membrane sealing assembly according to claim 16 or 17, wherein the at least one reinforcing region comprises a reinforcing region disposed on the first surface and a reinforcing region disposed on the second surface.

19. The membrane sealing assembly of claim 1 or 2, wherein the flow field plate is of the type in which the inlet region and / or the outlet region independently include recessed portions extending at least partially across the passage, and wherein the reinforcing member is positioned to be received by the recessed portions of the inlet region and / or the outlet region of the flow field plate.

20. The membrane sealing assembly according to claim 1 or 2, wherein the ion-conducting membrane extends into the boundary region.

21. The membrane sealing assembly according to claim 1 or 2, wherein the ion-conducting membrane includes a planar reinforcement member.

22. The membrane sealing assembly according to claim 1 or 2, wherein the internal region further comprises at least one catalyst layer located on the ion-conducting membrane.

23. The membrane sealing assembly according to claim 1 or 2, wherein the membrane sealing assembly is a rolled product.

24. A fuel cell, characterized in that... The fuel cell includes the membrane sealing assembly according to claim 1 or 2.

25. An electrolytic cell, characterized in that... The electrolytic cell includes the membrane sealing assembly according to claim 1 or 2.

26. A membrane module, the membrane module being combined with a flow field plate including an inlet port, an outlet port, and a flow field for providing at least one pathway between the inlet port and the outlet port, the flow field including an inlet region, an outlet region, and a main region located between the inlet region and the outlet region. The membrane assembly includes an ion-conducting membrane and a reinforcing component, wherein the ion-conducting membrane includes: An internal region, which is aligned with the main region of the flow field; and A boundary region that surrounds the interior region and is aligned with the inlet region and / or the outlet region of the flow field. The boundary region includes at least one port hole and at least one reinforcing region including the reinforcing member. The feature is that the at least one reinforcing region is in the form of a patch or strip, the patch or strip being disposed adjacent to at least one port hole present in the boundary region and between the at least one port hole and the inner region, such that the at least one reinforcing member is positioned on the ion-conductive film to extend at least partially across the inlet region and / or the outlet region of the flow field of the flow field plate, and The reinforced region has a stiffness greater than that of other regions of the ion-conducting film in the boundary region.

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