Method for manufacturing a membrane electrode assembly in continuous web form

Abstract

The present invention relates to first and second methods for the efficient, automated, precise and cost-effective manufacture of multi-layer, continuous web membrane electrode assemblies (11, 45) suitable for use in fuel cells, water electrolysis cells, electrochemical compressors and electrochemical sensors.

Description

[Technical field]

[0001] The present invention relates to first and second methods for the efficient, automated, precise and cost-effective manufacture of multi-layer, continuous web-like membrane electrode assemblies suitable for use in fuel cells, water electrolysis cells, electrochemical compressors and electrochemical sensors. [Background technology]

[0002] Methods for producing membrane electrode assemblies are known from the prior art. For example, EP 1629559 describes a method for producing a membrane coated with a catalyst, the so-called CCM (catalyst coated membrane). The CCM has a peripheral edge consisting of an edge material acting as a seal so that the reactant gases do not escape from the reaction area into the environment when the CCM is in use. A drawback of the above-mentioned method is that the catalyst coated membrane is used as a continuous sheet and most of the membrane surface is covered by the edge material. In other words, the overlap area between the membrane and the edge material is very large, so that most of the active area of ​​the membrane cannot be used, which results in a very low utilization of the membrane and high costs. Summary of the Invention [Problem to be solved by the invention]

[0003] It is therefore an object of the present invention to provide an efficient, automated, accurate and at the same time cost-effective method for producing a multilayer membrane electrode assembly in the form of a continuous web, which method can also be carried out simply and without high technical efforts. [Means for solving the problem]

[0004] The solution to this problem is provided by the independent claims. The dependent claims relate to advantageous further developments and embodiments of the invention.

[0005] The present invention thus solves the problem by a method, described in detail below, in which the membrane electrode assemblies are produced in the form of a continuous web. Each membrane electrode assembly consists of a layer assembly having a membrane arranged between an anode and a cathode. Furthermore, a frame-shaped seal is provided surrounding at least the outer edge of the layer assembly, and the inner area of ​​the layer assembly surrounded by the frame-shaped seal is exposed. In other words, a membrane electrode assembly is provided in which a membrane is introduced between an anode and a cathode to form a layer assembly, the layer assembly being surrounded by a window-shaped seal, such that the exposed window-shaped part of the layer assembly is surrounded by the frame-shaped seal.

[0006] The method includes first providing a first gasket material for producing a frame-shaped or frame-like gasket as a rolled material. Thus, the sealing material is initially present as a continuous material wound into a roll, not as a sealed portion. The first sealing material is disposed on a first protective film, which is also present in the rolled material.

[0007] Similarly, the second sealant is also provided as a roll material. Like the first sealant, the second sealant is also placed on a protective film, i.e., on the second protective film. The first sealant and the second sealant may be the same or different, whereby the similarities or differences may be related to chemical composition and / or geometric factors. It is essential for the present invention that the seal frame made from the first and second sealants prevents undesired leakage of reactant gas or reactant liquid, or gas or liquid generated during a reaction using the membrane electrode assembly.

[0008] Next, a step is performed of generating a first frame-shaped portion seal from the first sealing material so that the first protective film is not damaged, so that the generated first frame-shaped portion seal is still positioned on the first protective film.

[0009] Similarly, the second frame-shaped partial seal is also manufactured from the second sealing material. Again, the second frame-shaped partial seal is manufactured so that the second protective film is not damaged, so that the second partial seal remains on the second protective film.

[0010] Producing the partial seals according to the present invention is advantageous because the partial seals can be processed continuously in succession without cutting the respective protective films and there is no need to store, stockpile or transport them separately.

[0011] A first carrier film is then placed over the first partial seal. The carrier film may advantageously have a cover film, which is removed before the first carrier film is placed over the first partial seal.

[0012] The produced first frame-shaped partial seal is then fed to a first conveying medium with the first protective film removed and deposited thereon. The first conveying medium is not limited in detail but can preferably be in the form of a vacuum conveying belt, which allows the first partial seal to be conveyed effectively, simply, quickly and reliably and prevents deviation. The conveying medium can be provided as appropriate when a part needs to be conveyed.

[0013] In a further method step, the layer assembly material consisting of the anode, cathode and intervening membrane is provided as a roll material. This means that the anode, cathode and membrane are not yet cut into geometric dimensions suitable for the application, but a roll material is used in which continuous layers of the anode, cathode and intervening membrane are present in the form of a layer assembly. This facilitates the continuous production of membrane electrode assemblies (hereinafter also referred to as MEAs). In particular, the layer assembly material can be placed on a transport medium, such as another carrier film, which can effectively prevent damage. The carrier film can have an adhesive layer for better transport of the layer assembly material.

[0014] Next, the layer assemblies are cut from the layer assembly material and deposited on the first frame seal disposed on the carrier material. The cutting can be performed by a conventional device such as a cutting tool, a punch, etc. After the cut layer assemblies are deposited on the first frame seal, a second frame seal is provided and deposited on the layer assemblies disposed on the first frame seal, i.e., on the exposed upper side of the layer assemblies, whereby the second protective film is also removed here.

[0015] In this way, the first frame-shaped partial seal and the second frame-shaped partial seal circumferentially surround the layer assembly in the form of a seal frame, and the layer assembly is exposed inside. In other words, the window-shaped portion of the first frame-shaped partial seal and the window-shaped portion of the second frame-shaped partial seal are arranged in coincidence, and the layer assembly is arranged between them. A so-called assembly is created, whereby the assembly is composed of the first partial seal, the layer assembly, and the second partial seal in this order. Depending on how the layer assembly consisting of the anode, the cathode and the intervening membrane is arranged on the first partial seal, the orientation of the anode or the cathode relative to the first partial seal or the second partial seal can vary.

[0016] In order to achieve a good sealing effect, after the first partial seal, the layer assembly and the second partial seal are arranged one on top of each other, an adhesive is arranged on the first seal material and / or the second seal material, or a radiation curable agent is arranged on the first seal material and / or the second seal material, such that the adhesive or radiation curable agent is arranged between the first and second partial seals arranged one on top of each other.

[0017] The sealing effect of the frame-like seal formed from the first and second partial seals is then achieved by heat activation of the adhesive or radiation curing of the radiation curable agent, during which step further compression of the assembly is performed to connect the first and second partial seals with the layer assembly. In this way, a membrane electrode assembly with a frame-like seal is obtained as a continuous roll on a first carrier material, which continuous roll can be placed on a web-like transport material and further processed in a continuous process or transported for storage.

[0018] Thus, according to the invention, a method for manufacturing a continuous web of membrane electrode assemblies is provided, which method exhibits advantages over the prior art with regard to an efficient, automated and technically and logistically manageable production of membrane electrode assemblies, where continuous and therefore time-efficient component guidance and handling is always ensured.

[0019] According to the invention, a membrane electrode assembly is produced in which there is a catalyst-coated membrane, which can be considered as a composite consisting of an anode, a cathode and a membrane located between the anode and the cathode, in particular a membrane capable of conducting protons. The catalyst-coated membrane is in the form of a continuous web, in other words in a roll (after winding the continuous web). The membrane assembly is surrounded by a specially designed sealing frame, which is designed to surround the anode, the cathode and the membrane at their ends. That is to say, after the first and second partial seals are connected, the cathode, the anode and the membrane of each membrane assembly are surrounded on all sides by a frame-like seal at their outer edges. A frame-like seal or sealing frame is understood to mean a sealing structure that has a shape like a picture frame or a window frame and has a free inner area inside the membrane electrode assembly between the respective inner edges of the sealing frame, and has a shape like a cut-out of a picture frame or a window frame. In this inner area, at least the overlapping parts of the cathode, the anode and the membrane are exposed and therefore not covered by the sealing frame. Here, the sealing frame can only contact the ends of the anodes, cathodes and membranes, or the anodes, cathodes and / or membranes can partially overlap in the layer thickness direction of the MEA, i.e. in the arrangement direction of the layers of the MEA, which also corresponds to the stacking direction of the MEA, i.e. in the arrangement direction of the anodes, membranes and cathodes. The sealing frame is formed from a first partial seal and a second partial seal, which are glued together by adhesive or by radiation curing of an applied radiation curable agent and compression of the assembly, in particular with a material bond and are therefore mechanically stable.

[0020] Membrane electrode assemblies produced according to the present invention can be used, for example, in fuel cells, water electrolysis cells, electrochemical compressors, and electrochemical sensors.

[0021] According to a further development which is advantageous in terms of a continuous and time-efficient process control, the production of the first and second frame-shaped part seals is carried out by rotary punching, flat punching or laser cutting window-shaped cutouts from the first and second sealing materials. The above-mentioned process is characterized by very low losses and high precision.

[0022] It is furthermore advantageous if the first seal and the second seal are guided in opposite directions, which has the advantage of a space-saving processing method.

[0023] The first and second partial seals are joined particularly efficiently by pre-fixing them by guiding them through a pair of rollers, at least the first of which is designed with an elastic material, prior to heat activation of the adhesive or radiation curing of the radiation curable agent. The elastic material can be used to urge the partial seals against each other, such that air pockets between the first and second partial seals are effectively prevented.

[0024] To prevent deviation of the individual parts of the assembly to be joined together, the heat activation or radiation curing and compression is preferably performed by guiding the assembly through a fixture where heat energy and pressure or radiation and pressure are applied to the assembly, thereby reducing the amount of scrap of the membrane electrode assembly.

[0025] To make the thermal activation particularly efficient and thereby prevent damage to the assembly, the fixture is preferably heated to a temperature of 80°C to 160°C, more preferably 100°C to 140°C, and the thermal energy can be applied symmetrically or asymmetrically. If a radiation curable agent is used, radiation in the wavelength range of 450nm to 100nm, preferably 420nm to 365nm, is preferably selected and applied to the exposed upper and exposed lower sides of the product to be produced, i.e. the assembly material that is not yet cured. By exposed side is understood the side of the assembly that is not on the carrier material. In the simplest case, the radiation is supplied from the exposed upper side of the second part seal.

[0026] It is particularly advantageous in terms of good sealing properties if the pressure applied to the assembly by the fastener is between 0.05 MPa and 10 MPa, preferably between 0.15 MPa and 5 MPa, and even more preferably between 0.25 MPa and 3 MPa. In the pressure range up to 10 MPa, the first and second partial seals can be compressed together to form an air-free seal frame, whereby the lower the pressure, the more effectively damage to the seal material and possibly to the components of the assembly can be avoided. Taking into account the above advantages, pressures of 0.25 MPa to 3 MPa are particularly suitable.

[0027] It is again advantageous if compression takes place for between 0.006 and 60 seconds, preferably between 0.2 and 120 seconds, more preferably between 0.25 and 5 seconds.

[0028] According to a further advantageous further development, the layer assembly is cut out from the layer assembly material in such a way that the area of ​​the layer assembly surrounded by the frame-shaped first and second partial seals is larger than the window-shaped cutouts of the first and second partial seals, so that the partial areas of the layer assembly overlap the partial seals, resulting in a particularly good layer bond and effectively preventing leakage between the layer assembly and the seal frame.

[0029] Preferably, the cut layer assemblies are transported to a transport medium before being deposited on the first frame-like partial seal, and are transported from the first transport medium to a second transport medium such that the individual layer assemblies are spaced apart. The spacing is advantageous for improving the accurate fitting arrangement of the layer assemblies onto the first partial seal, so that the largest inner area of ​​the layer assemblies is available for catalytic reactions when the membrane electrode assembly is subsequently used.

[0030] Further advantageously, the layer assembly material includes a layer assembly carrier film, which allows the layer assembly material to be transported effectively without distortion, whereby cutting of the layer assembly is performed in such a way that the layer assembly carrier film is not cut, thereby facilitating continuous processing of the layer assembly.

[0031] According to a further advantageous further development, the layer assembly carrier film is removed from the layer assembly before the layer assembly is deposited on the first frame-shaped part seal at an angle of more than 90 °, preferably more than 105 °, more preferably more than 120 °. Peeling off the layer assembly carrier film at an angle of 90 ° or more prevents deformation or (partial) peeling off of the components of the layer assembly particularly well and is therefore particularly gentle. The larger the angle, the easier and more efficient the layer assembly carrier film can be removed.

[0032] More advantageously, during the creation of the first frame-shaped partial seal in the first seal material, fiducial marks are additionally created to align the first partial seal, the layer assembly and the second partial seal with respect to each other in the machine direction. The fiducial marks are provided so that the position of the window-shaped cut of the partial seal can be accurately determined, thereby minimizing the overlap area between the membrane and the partial seal. The fiducial marks also facilitate the separation of the layer assembly (catalyst coated membrane) placed on the first partial seal by appropriate process control, and the spacing of the individual layer assemblies from each other.

[0033] To facilitate the positioning of the components of the assembly to be placed relative to each other, the method further comprises the step of adjusting the width of the first conveying medium to the width of the first carrier film. This means that the guidance of the component (first partial seal) on the conveying medium is thereby locally limited. For example, if a vacuum belt conveyor is used as the conveying medium, the width of the vacuum applied to it can be specially adapted to the components to be conveyed, so that bypass for air is prevented, no air leaks occur and the vacuum can be particularly stable, so that the position of the first frame-shaped partial seal is particularly well stabilized against deviations.

[0034] In order to save processing times and at the same time ensure deviation-free transport, the web speed of the first transport medium is in particular between 0.1 m / min and 100 m / min, preferably between 0.5 m / min and 50 m / min, and more preferably between 1 m / min and 40 m / min.

[0035] Furthermore, in order to particularly effectively prevent consequential damage due to temperature effects on the membrane electrode assembly, it is further advantageously provided that the membrane electrode assembly is cooled after compression.

[0036] In order to protect the first and / or second partial seal, preferably a first protective film is provided on the exposed surface of the first seal and / or a second protective film is provided on the exposed surface of the second seal, and the frame-shaped partial seal is guided to a correct position during removal of the first protective film and / or the second protective film from the frame-shaped partial seal. Removal of the first and / or second protective film is preferably performed after the first and / or second partial seal are manufactured. The protective film has the advantage of preventing contamination of the seal.

[0037] More advantageously, the membrane electrode assembly can be cut to final contour after the assembly has been compressed.

[0038] Depending on how further processing of the membrane electrode assemblies is intended, with or without a final contour cut, the membrane electrode assemblies may remain on the carrier film or may be singulated as piece goods, separated from the carrier film, and stacked.

[0039] In order to improve the quality of the produced membrane electrode assemblies, each membrane electrode assembly is clearly labeled or marked, and the label is advantageous to check the consistency and quality identification.

[0040] Furthermore, it is advantageous from the point of view of quality improvement that after each method sequence the quality of the obtained membrane electrode assembly is checked by an inspection system and, in case of a component being defective, a defect mark, preferably a mark such as a Data Matrix / QR Code, is applied so that the defective component can be recognized and sorted out in subsequent further processing steps.

[0041] Further advantageously, each membrane electrode assembly is uniquely labeled or marked and the labels are checked for consistency and quality identification.

[0042] Further advantageously, after each method sequence, the quality of the obtained membrane electrode assembly can be checked by an inspection system, and in case of defects, a defect mark can preferably be applied to the mark so that the defective part can be recognized and sorted out in subsequent further processing steps.

[0043] The present invention also provides a second method for producing a membrane electrode assembly, in which the membrane electrode assembly is also obtained in the form of a continuous web comprising a layer assembly comprising a membrane between a cathode and an anode, a frame seal and a gas diffusion layer, the frame seal surrounding at least the outer edge of the layer assembly such that an inner region of the layer assembly surrounded by the frame seal is exposed.

[0044] The method thus provides a step of providing a membrane electrode assembly in the form of a roll material having a cathode, an anode and a membrane arranged therebetween, and a sealing frame surrounding at least the outer edge of the membrane electrode assembly. The membrane electrode assembly can be produced according to the first method of the invention described above and is then placed on a first carrier film. Thus, each of the advantageous further embodiments, benefits and effects of the first method according to the invention also apply to the second method according to the invention.

[0045] Further, the second method according to the present invention includes disposing a first gas diffusion layer on a first side of the membrane electrode assembly and / or disposing a second gas diffusion layer on a second side of the membrane electrode assembly. In particular, the first carrier film, if present, can be removed prior to disposing the first gas diffusion layer or the second gas diffusion layer.

[0046] Advantageously, the membrane electrode assembly with the gas diffusion layer can be further guided, for example, onto a second carrier film on which the first gas diffusion layer is arranged, which improves the continuous process with the membrane electrode assembly as roll material.

[0047] Due to the use of membrane electrode assemblies as roll material in the second method according to the invention and their further processing as roll material, the second method according to the invention is also characterized by the fact that it is fast, reliable, cheap and can be carried out in a largely automated manner.

[0048] In particular, the membrane electrode assembly may include a gas diffusion layer as an outer layer on each side, i.e. the cathode side and the anode side. The gas diffusion layer may be provided as piece goods in a storage unit, or the gas diffusion layer may be separated into piece goods from a roll of gas diffusion layer provided as roll material before the gas diffusion layer is used. In this case, the gas diffusion layer is preferably arranged on a second carrier film, at least after separation. To provide the gas diffusion layer, an advantageous further development method includes arranging a first gas diffusion layer on a first side of the membrane electrode assembly and / or arranging a second gas diffusion layer on a second side of the membrane electrode assembly. The first side may be, for example, the cathode side, so that the second side is the anode side. Alternatively, the first side may be the anode side and the second side may be the cathode side. The gas diffusion layer serves to distribute the reactant gas on the respective side of the membrane electrode assembly.

[0049] Advantageously, before placing the first gas diffusion layer and / or the second gas diffusion layer on the edge region of the first side of the membrane electrode assembly and / or on the edge region of the second side of the membrane electrode assembly, an adhesive, an adhesion promoter or a double-sided adhesive film is applied, thereby improving the adhesion of the gas diffusion layers. According to another embodiment, the frame seal can also be softened for this purpose. If an adhesive film is used, the adhesive can be selected, for example, from air-curing adhesives, heat-activatable adhesives, light-activatable adhesives, UV-activatable adhesives or two-component adhesives, whereby the adhesive can be applied in a concentration of 0.1 to 10 mg cm. -1 An amount of adhesive is advantageously used or the layer thickness of the applied adhesive layer is between 1 and 30 pm. If the adhesive is a UV-activatable adhesive, the wavelength of the activating UV light is advantageously in the range of 100 nm to 440 nm, preferably 300 nm to 400 nm, more preferably 350 nm to 420 nm, in particular 395 nm. The UV intensity is also advantageously in the range of 1 to 30 W / cm, the exposure time can be about 0.003 s to 60 s depending on the width of the adhesive film, the exposure width being advantageously adapted to the width of the applied adhesive. In this embodiment of the method according to the invention, the gas diffusion layer can be applied gently, so that folding of the gas diffusion layer and thus damage to the gas diffusion layer is avoided, and an accurate positioning of the gas diffusion layer is still possible.

[0050] In order to improve the permanent positioning of the gas diffusion layers and subsequently allow a positionally accurate fixing of the gas diffusion layers, the method advantageously comprises fixing the first and / or second gas diffusion layers on the first and / or second faces of the membrane electrode assembly, in particular by applying a temperature of 100-200°C, preferably 140-180°C, and further advantageously by applying a pressure of 0.5-5 MPa, preferably 1.0-5.0 MPa.

[0051] For an accurate adapted positioning of the gas diffusion layer, it is further advantageously provided that the position of the window-like cutout of the frame seal or the reference mark of the membrane electrode assembly is detected, the positioning of the first gas diffusion layer on the second transport medium or the position of the window-like cutout is detected, or the position of the reference mark of the first surface of the membrane electrode assembly in the machine direction (which corresponds to the transport direction of the membrane electrode assembly) and in the cross machine direction (which corresponds to the direction perpendicular to the machine direction in the surface expansion direction of the membrane electrode assembly) is adapted.

[0052] To further facilitate the method, in particular also for its spatial compactness, according to a further advantageous further development, the transport direction of the membrane electrode assembly and the transport direction of the first gas diffusion layer are selected such that they are opposite and / or horizontal before the gas diffusion layer and the membrane electrode assembly are brought together.

[0053] In order to improve the quality of the finally manufactured membrane electrode assemblies, the method can also include, inter alia, a gas tightness test, in which the membrane electrode assemblies with the first and second gas diffusion layers are placed in a sealing fixture unit, and the gas tightness of each of the membrane electrode assemblies is determined using a test gas. This gas tightness test can be incorporated into the continuous transport process of the membrane electrode assemblies, improving the convenient and time-saving manufacture of high-performance membrane electrode assemblies.

[0054] Further advantageously, the membrane electrode assembly can be cut to a final contour after compressing the assembly or after positioning and fixing the first gas diffusion layer on the first side of the membrane electrode assembly and / or the second gas diffusion layer on the second side of the membrane electrode assembly.

[0055] Depending on how the further processing of the membrane electrode assembly is intended, the membrane electrode assembly with or without the final contour cut either remains on the (second) carrier film or is singulated as piece goods, separated from the carrier film and stacked.

[0056] In order to improve the quality of the produced membrane electrode assemblies, each membrane electrode assembly is clearly labeled or marked, and the label is advantageous to check the consistency and quality identification.

[0057] Furthermore, it is advantageous from the point of view of quality improvement that after each method sequence the quality of the obtained membrane electrode assembly is checked by an inspection system and, in case of a defective part, a defect mark, preferably a mark such as a Data Matrix / QR code, is applied so that the defective part can be recognized and sorted out in subsequent further processing operations.

[0058] Further advantageously, each membrane electrode assembly is uniquely labeled or marked and the labels are checked for consistency and quality identification.

[0059] Further advantageously, after each method sequence, the quality of the obtained membrane electrode assembly can be checked by an inspection system and, in case of defects, a defect mark can preferably be applied to the mark so that the defective part can be recognized and sorted out in subsequent further processing steps.

[0060] Further detailed advantages and features of the present invention will become apparent from the following detailed description of the embodiments with reference to the drawings. [Brief description of the drawings]

[0061] [Figure 1] FIG. 1 is a schematic diagram illustrating the steps of a method for manufacturing a three-layer membrane electrode assembly according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a schematic diagram illustrating steps of a method for manufacturing a five-layer membrane electrode assembly according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0062] Only essential aspects and components of the invention are shown in the figures. All other aspects have been omitted for clarity. Furthermore, identical reference numbers refer to identical device parts / components.

[0063] Figure 1 shows in detail, by means of a schematic apparatus, the method steps for manufacturing a three-layer membrane electrode assembly in the form of a three-layer continuous web for use in fuel cells, water electrolysis cells, electrochemical compressors and electrochemical sensors, the membrane electrode assembly including a sealing frame consisting of first and second partial seals and a catalyst coated membrane (CCM). The method steps are divided into modules 1 to 4. The method is fast, reliable and cost-effective.

[0064] In the module 1, the first seal material 1 is supplied as a roll material from a first roller 20. The first seal material 1 is provided with a first protective film 3 on its upper side. The first seal material 1 is first aligned, i.e. arranged wrinkle-free in the cross machine direction Q and centered with respect to the width of the device. The first seal material 1 arranged with the first protective film 3 is then fed to a cutting device 23 consisting of a third roller 23a and a rotary cutter 23b (which may be a flat die cutter or a laser cutter). Then, the first carrier film 2 with the cover film 2a is supplied from a second roller 21, and after removing the cover film 2a and further winding it up around the roller 21a, the first seal material 1 and the first carrier film 2 are guided onto a guide roller 22 (a pair of rollers) so that the first seal material 1 is placed on the first carrier film 2. Then, while peeling off the protective film 3 including the sealing material scraps of the sealing material 1, a first partial seal 6 is formed from the first sealing material 1 using a peeling roller 23c, and since this first partial seal 6 has a frame-like or window-frame-like shape, a window-like cut is formed in the inner peripheral edge of the first partial seal 6. The first protective film 3 from which the sealing material has been cut off is taken up by a fourth roller 24.

[0065] In module 2, firstly, a reference mark is applied to the first partial seal 6 by the marking device 25 and the created marking is checked by the marking checking device 25a. The reference mark can be applied, for example, by punching, cutting or laser irradiation. In an advantageous further development of the method, a reference mark is additionally created in the first partial seal 6 by the same tool in the same step in which the window-shaped cutout is created. By simultaneously creating the window-shaped cutout and the reference mark in the first sealing material 1 in one step, in particular using the same tool in a rotary cutting step, a precise positioning of the reference mark with respect to the window-shaped cutout is achieved. The reference mark and thus the exact position of the window-shaped cutout is preferably recorded by means of a camera system. The reference mark can be detected in subsequent steps via a sensor or camera system and serves as a clock for the alignment of all other components, i.e. the layer assembly 7 and the second partial seal 8a, and thus for the alignment of the layer assembly 7 and the second partial seal 8a in the machine direction M with respect to the first partial seal 6. In this way, a very stable process control is achieved with respect to the alignment of the downstream components, i.e. the layer assembly 7 and the second partial seal 8a. The fiducial marks can be detected by cameras and / or sensors to generate signals for synchronizing and timing the layer assembly 7 and the second partial seal 8a. Furthermore, the feed speed of the layer assembly 7 and the second partial seal 8a can be controlled so that they are accurately positioned with respect to the first partial seal 6. The position of the layer assembly 7 is determined in particular by a camera system which detects the edge of the layer assembly 7 in the machine direction M and converts it into a signal that can be synchronized with the signal of the fiducial marks of the first partial seal 6.

[0066] Furthermore, the layer assembly material 4, consisting of the anode, cathode and intervening film, is fed from the fifth roller 26 in the form of a roll material. The layer assembly material 4 is centered in the cross machine direction Q relative to the width of the device. The exact position of the layer assembly material 4 in the cross machine direction Q can be fine-tuned by using additional guide rollers 22. The layer assembly material 4 is fed onto a layer assembly carrier film 5, which is fed to a cutting device 27 consisting of a sixth roller 27a and a rotary cutter 27b, in which a layer assembly 7 is produced from the layer assembly material 4, the format of which is adapted to the window-like cutout of the first partial seal 6. In particular, the format of the layer assembly 7 is selected to be larger than the format of the window-like cutout of the first partial seal 6, so that an overlap area with the first partial seal 6 is formed at the periphery of the layer assembly 7. In particular, the overlap area is selected to be large enough to form an airtight assembly of the layer assembly 7 and the frame-like seal, but small enough to minimize loss of the active area of ​​the layer assembly 7. The overlap area is preferably in the range of 0.5 mm to 6 mm, more preferably in the range of 1 mm to 3 mm.

[0067] The layer assembly 7, still placed on the layer assembly carrier film 5, is guided via guide roller 22 so that the layer assembly 7 is placed on the first partial seal 6 while peeling off the layer assembly carrier film 5, and is then wound up by a seventh roller 28. Accurate positioning of the layer assembly 7 in the frame-shaped first partial seal 6 is achieved by aligning the layer assembly 7 with reference marks provided on the first partial seal 6.

[0068] The module 3 thus has a first partial seal 6 on a first carrier film, on the upper side of which the layer assembly 7 is arranged.

[0069] In module 3, the second sealant 8 is fed from the eighth roller 28a onto the second protective film 9. As can be seen from a comparison of modules 1 and 3, the first sealant 1 and the second sealant 8 are guided in opposite directions, which allows a particularly compact design and layout of the device to be achieved. The second sealant 8 is fed to a cutting device 29 consisting of a ninth roller 29a and a rotary cutter 29b, in which the second partial seal 8a is produced by removing the second protective film 9 from the second sealant 8, such that the window-shaped cutout of the first partial seal 6 overlaps the window-shaped cutout of the second partial seal 8a produced in the cutting device 29. The layer assembly is placed inside the window-shaped cutout in such a way that the largest possible area of ​​the membrane is exposed inside the frame-shaped partial seal 6, 8a. After being peeled off, the second protective film 9 is wound up on a tenth roller 29c. As already described for the first partial seal 6, the second partial seal 8a may also be provided with reference marks to facilitate positioning of the second partial seal 8a on the first partial seal 6.

[0070] The first partial seal 6, the layer assembly 7 and the second partial seal 8a are stacked one on top of the other in that order in the direction B to form an assembly 10 in the sense of the present invention.

[0071] In the module 4, the first and second partial seals 6, 8a are fixed together with the layer assembly 7 in a fixture 30, in particular after checking the layer assembly 7 produced to date by means of a sensor D. For this purpose, an adhesive is placed on the first seal 1 and / or on the second seal 8 in such a way that after the first partial seal 6, the layer assembly 7 and the second partial seal 8a are placed on top of each other, the adhesive is placed between the first and second partial seals 6, 8a, which are placed on top of each other. The adhesive is then thermally activated and the assembly 10 is compressed in the fixture 30, which can be designed, for example, as a heated pair of pressing jaws, to obtain a membrane electrode assembly 11 with a frame-shaped seal as a continuous roll on the carrier film 2. The adhesive is used to obtain a physically bonded, mechanically stable and gas-tight composite of the layer assembly 7 and the sealing frame.

[0072] The pair of pressing jaws for fixing the partial seals and producing the seal frame, or the optional pair of rollers for fixing, can be made of different materials, in particular selected from the group of metal, rubber, rubberized metal or coated metal. The materials are also selected so that the continuous web assembly 10 does not stick to the pressing jaws or rollers. The material of the pressing jaws or rollers is designed so that the pressure is homogeneously distributed during fixing and the thickness difference of the overlapping parts of the partial seals and layer assemblies is even. The coating is selected, for example, from Viton or PTFE.

[0073] Furthermore, the temperatures of the upper and lower pressing jaws of the pair of pressing jaws or the upper and lower rollers of the pair of rollers may be different. In particular, the temperature of the respective lower element is between 40° C. and 160° C., preferably between 50° C. and 140° C., and the temperature of the respective upper element is between 80° C. and 200° C., preferably between 100° C. and 180° C. Furthermore, in particular, the pair of pressing jaws or the pair of rollers generates a pressure between 0.05 MPa and 10 MPa, preferably between 0.15 MPa and 5 MPa, more preferably between 0.25 MPa and 3 MPa. In this way, a sufficient activation of the adhesive is achieved and a materially bonded and bubble-free connection between the layer assembly and the first and second part seals is achieved.

[0074] In an advantageous further development of the method, the pair of pressing jaws is arranged to move on rails, which facilitates a continuous process control, since the sealing process of the two part seals follows the movement of the continuous web in the machine direction M. A continuous process control is particularly efficient and also increases the accuracy of the method, since interruptions in the movement of the web in the sense of periodic stopping and starting of the web are avoided.

[0075] In a further advantageous development of the method, the composite of the layer assembly and the first and second partial seals, the so-called assembly, is cooled after being clamped between a pair of pressing jaws on a cooled conveyor belt or between a pair of rollers, which step hardens the adhesive and improves the cutting ability of the partial seals.

[0076] The membrane electrode assembly 11 with the frame seal obtained as a continuous roll can then be wound up on the eleventh roller 29d. This is possible because the membrane electrode assembly 11 is still on the first carrier film 2.

[0077] Advantageously, in the devices A, B, C, E, F and G provided as examples, a data matrix code (DataMatrixCode) can be applied and controlled. For this purpose, for example, a data matrix code can be applied in the device A, a check of the data matrix code can be performed in the device B, a QC-CCM, i.e. a quality control of the membrane electrode assembly 7 (CCM) by means of an optical inspection system can be performed in the device C, and a QC-3-L, i.e. a quality control of the 3-layer membrane electrode assembly 7 (CCM) by means of an optical inspection system can be performed in the device E, i.e. a quality control of the 3-layer MEA (both sides) by means of an optical inspection system, which allows a quality and / or gas leakage test of the composite of the layer assembly and the first and second partial seals. Furthermore, a device F for defect marking can also be provided and / or a defect mark verification can be performed in the device G.

[0078] As shown in Figure 1, this method leads to the production of a continuous web of three-layer membrane electrode assemblies (membrane with anode and cathode) and shows advantages over traditional methods in terms of efficiency in process control, automation and transportation, always ensuring continuous and therefore time-efficient component guidance and processing.

[0079] The produced three-layer membrane electrode assembly 11 is provided with a catalyst-coated membrane, which can be considered as a composite of an anode, a cathode, and a membrane, specifically a proton-conducting membrane, located between the anode and the cathode. The catalyst-coated membrane is in the form of a continuous web, or in other words a roll (after the continuous web is wound up), and is surrounded by a specially designed sealing frame.

[0080] 2 shows in detail, by means of a schematic apparatus, the method steps for the manufacture of a five-layer membrane electrode assembly 45 in the form of a five-layer continuous web for use in fuel cells, water electrolysis cells, electrochemical compressors and electrochemical sensors, the membrane electrode assembly 45 having a sealing frame containing first and second partial seals and a catalyst coated membrane (CCM) together with gas diffusion layers. The method steps are divided into modules 5 to 8. The method is fast, reliable, cost-effective and can be largely automated.

[0081] In the method shown in Figure 2, a three-layer membrane electrode assembly 11 can be used, which is manufactured according to the first method and device as shown in the schematic diagram of Figure 1. What is essential here is that the membrane electrode assembly used is present as a roll material supported on a first carrier film 2, comprising a membrane, an anode and a cathode sandwiching the membrane on opposite sides thereof, and a sealing frame surrounding the membrane.

[0082] In module 5, the membrane electrode array 11 obtained as a continuous roll material is present on the first carrier film 2 on the eleventh roller 29d, from which it is unwound, its assembly being checked by a sensor H, and fed to a first adhesive applicator 31, where an adhesive is applied to the exposed top surface of the membrane electrode array 11, covering at least a partial area of ​​the frame-like seal, and then cured in an adhesive curing device 32. The vertical line between the adhesive applicator 31 and the curing device 32 represents a protection device 32a, which protects the adhesive from premature solidification.

[0083] The adhesive is in particular selected from the group of air-curing, heat-activated, light-activated, UV-activated or two-part adhesives. The adhesive can be applied to the periphery of the window cut of the frame seal by a single application system or by two application systems, each applying an L-shaped adhesive pattern, or by several application systems, each applying a linear adhesive pattern. The application system is a system well known to those skilled in the art and can be understood as a system of pumps and nozzles suitable for applying adhesive to the periphery of the window cut.

[0084] Next, in module 6a, a second carrier film 48 is unwound from a thirteenth roller 46 provided with a protective cover film 49. The cover film 49 is removed as the second carrier film passes through a pair of rollers 22 and is taken up by a fourteenth roller 47.

[0085] Further, in the module 6a, the prepared and adjusted gas diffusion layer 12 is transferred from the magazine 33 to the second carrier film 48 and supplied to the gas diffusion layer coating device 34, where the gas diffusion layer 12 is supplied to the upper surface of the membrane electrode assembly 11 on which the adhesive has been provided, and pressed by the pressing device 38. After passing through the pressing device 38, the first carrier film 2 is peeled off and taken up by the twelfth roller 29e.

[0086] The membrane electrode assembly of module 6b is then fed to a second adhesive applicator 35, where adhesive is applied to the exposed second top side of the membrane electrode assembly. A further gas diffusion layer 12 is then fed from a magazine 36 to the second top side of the membrane electrode assembly to which adhesive has been applied. The gas diffusion layer 12 is then pressed against the membrane electrode assembly 11 by a fifteenth roller 38. The membrane electrode assembly 11 and the gas diffusion layer 12 are held on the first top side by a vacuum conveyor belt 37, which holds the membrane electrode assembly 11 with the gas diffusion layer 12 while it is further conveyed, exposing the underside of the membrane electrode assembly 11 and the underside gas diffusion layer 12.

[0087] Furthermore, the position of the window cuts in the partial seal can be detected by the sensor H and the positioning of the first gas diffusion layer 12 on the vacuum conveyor belt 37 can be adapted to the position of the window or frame cuts in the machine direction M and cross machine direction Q. This allows for accurate positioning of the first gas diffusion layer 12 relative to the window cuts, resulting in a composite with high power density and long life.

[0088] In module 7, the final contour cutting of the membrane electrode assemblies with gas diffusion layers 12 is carried out by a cutting device 39 so that the carrier film 1 is not damaged and thus the membrane electrode assemblies with gas diffusion layers 12 are still arranged on the first carrier film 1. The membrane electrode assemblies can either be separated from one another by the cutting device 39 and prepared for singulation or remain unseparated and available as roll material. Furthermore, quality control is carried out by a camera system 40, which consists of a camera that checks the cutting quality and the dimensions of the window-like cuts, so that the use of the correct and valid tools is guaranteed.

[0089] The membrane electrode assembly 45 with the gas diffusion layer 12 is transported on a transport medium 41, the second carrier film 48 is removed from the membrane electrode assembly by being wound up on the sixteenth roller 42, and the finished membrane electrode assembly 45 is subjected to a final quality control in the module 8 by a camera system 43 before being sorted out if its quality is not sufficient or, if its quality is sufficient, is stocked in a storage container 44 for further processing or storage. Another camera system 43 can also be mounted above and below the continuous web, checking the alignment of the layer assembly with the first partial seal and the alignment of the layer assembly with the second partial seal. This ensures that the window-like cuts of the first and second partial seals are aligned in coincidence. Furthermore, this camera system can check the quality of the pre-fixing of the edge film with regard to the absence of wrinkles and air bubbles. Furthermore, an additional camera (QC camera) can check the quality of the sealed composite of the layer assembly with the first and second partial seals with regard to the absence of air bubbles and wrinkles.

[0090] Also, according to the method shown in FIG. 2 or the schematic apparatus for carrying out the method, the method results in the production of a continuous web of membrane electrode assemblies, which are now five layers (cathode, anode and membrane with two gas diffusion layers), and represents an advantage over conventional methods in terms of efficiency in process control, automation and transportation, which ensures continuous and therefore time-efficient component guidance and processing at all times.

[0091] In the fabricated 5-layer membrane electrode assembly, the catalyst coated membrane and the gas diffusion layers are present and precisely positioned. The 5-layer membrane electrode assembly is in the form of a continuous web on a roll or can be cut to size for further processing.

[0092] The apparatus shown in Figure 2 can alternatively be used to provide a three-layer membrane electrode assembly with a final contour cut, in which case the gas diffusion layers are not transported from the magazines 33 and 36.

[0093] In addition to the above detailed description of the invention, explicit reference is made to the drawings in FIG. 1 and FIG. 2 for a supplementary disclosure thereof. [Explanation of symbols]

[0094] 1 First sealing material 2. First carrier film 2a Cover film 3 First protective film 4-layer assembly material 5 layer assembly carrier film 6 First Part Seal 7-layer assembly material 8 Second sealing material 8a Second Part Seal 9 Second protective film 10 Assembly 11 Membrane electrode assembly 12 Gas diffusion layer 20 First Roller 21 Second Roller 21a Other rollers 22 Guide roller 23 Cutting device 23a 3rd Roller 23b Rotary blade 23c Peeling roller 24 4th Roller 25 Marking device 26 5th Roller 27 Cutting device 27a 6th Roller 27b Rotary cutter 28 7th Roller 28a 8th Roller 29 Cutting device 29a 9th Roller 29b Rotary blade 29c 10th Roller 29d 11th Roller 29e 12th Roller 30 Fixtures 31 First adhesive application device 32 Curing equipment 32a Protective device 33 Magazine 34 Gas diffusion layer coating device 35 Second adhesive application device 36 Magazine 37 Vacuum conveyor belt 38 15th Roller 39 Cutting device 40 Camera System 41 Transport media 42 16th Roller 43 Camera System 44 Storage Containers 45 Membrane electrode assembly with gas diffusion layer 46 13th Roller 47 14th Roller 48 2nd Career Film 49 Cover Film A. Device for applying data matrix code B. Device for checking data matrix codes C. Membrane electrode array quality control device D-Sensor E. Quality control device for three-layer membrane electrode array F Defect marking device G Defect mark verification device H-sensor [Prior art documents] [Patent documents]

[0095] [Patent Document 1] European Patent Publication No. 1629559

Claims

1. A method for producing membrane electrode assemblies (11) in the form of a continuous web, each of which comprises a layer assembly (7) having a membrane arranged between an anode and a cathode, and a frame seal surrounding at least the outer edge of the layer assembly (7) such that an inner area of ​​the layer assembly (7) surrounded by the frame seal is exposed, the method comprising the steps of: providing a first seal material (1) as a roll material, said first seal material (1) being disposed on a first protective film (3); providing a second seal material (8) as a roll material, said second seal material (8) being disposed on a second protective film (9); A step of producing a first frame-shaped partial seal (6) from the first sealing material (1) so as not to damage the first protective film (3); placing a first carrier film (2) on the first partial seal (6); generating a second frame-shaped partial seal (8a) from the second sealing material (8) so as not to damage the second protective film (9); supplying and depositing the first frame-shaped partial seal (6) on a web-shaped carrier material disposed on a first carrier medium while peeling off the first protective film (3); Providing a layer assembly material (4) consisting of an anode, a cathode and a membrane therebetween as a roll material; cutting a layer assembly (7) to size from said layer assembly material (4); depositing a layer assembly (7) on said first frame-shaped partial seal (6) arranged on a carrier; supplying and depositing the second frame-shaped partial seal (8a) on the layer assembly (7) arranged on the first frame-shaped partial seal (6) while removing the second protective film (9) so that the window-shaped cuts of the first frame-shaped partial seal (6) and the window-shaped cuts of the second frame-shaped partial seal (8a) are arranged to coincide with each other to obtain an assembly (10), wherein, after the first partial seal (6), the layer assembly (7) and the second partial seal (8a) are arranged on top of each other, an adhesive or a radiation curing agent is arranged on the first sealing material (1) and / or the second sealing material (8) such that the adhesive or the radiation curing agent is arranged between the first and second partial seals (6, 8a) arranged on top of each other; thermally activating the adhesive or radiation curing the radiation curable agent; compressing the assembly (10) disposed on said web-like carrier material to obtain a membrane electrode assembly (11) having a frame-like seal as a continuous roll of material; A method for producing a membrane electrode assembly (11) comprising:

2. 2. The method according to claim 1, wherein the step of generating the first and second frame-shaped partial seals (6, 8a) is carried out by forming window-shaped cuts from the first seal material (1) and the second seal material (8) by rotary punching, flat punching or laser cutting.

3. the first seal (1) and the second seal (8) are guided in opposite directions, and / or 3. The manufacturing method according to claim 1 or 2, wherein the first partial seal (6) and the second partial seal (8a) are pre-fixed by being guided through a pair of rollers before the adhesive is thermally activated or the radiation curable agent is radiation cured, and at least one of the rollers is mounted by an elastic material.

4. The method of claim 1 , wherein the heat activation or radiation curing and compaction is accomplished by guiding the assembly (10) through a fixture (30) where thermal energy and pressure or radiation and pressure are applied to the assembly (10).

5. 5. The method of claim 4, wherein the fixture (30) is heated to a temperature of 80° C. to 160° C., preferably 100° C. to 140° C., and thermal energy is applied symmetrically or asymmetrically or radiation in the wavelength range of 450 nm to 100 nm, preferably 420 nm to 365 nm is irradiated to the exposed upper and lower surfaces of the assembly (10).

6. The method according to claim 4 or 5, wherein the pressure applied to the assembly (10) by the fixture (30) is between 0.05 MPa and 10 MPa, preferably between 0.15 MPa and 5 MPa, more preferably between 0.25 MPa and 3 MPa.

7. said compression is carried out for a period of time between 0.006 seconds and 60 seconds, preferably between 0.2 seconds and 120 seconds, more preferably between 0.25 seconds and 5 seconds; and / or said cutting of the layer assembly (7) from said layer assembly material (4) to the desired size is performed in such a way that the area of ​​said layer assembly (7) enclosed by said frame-like first and second partial seals is larger than the window-like cuts of said first and second partial seals (6, 8a); and / or 6. The manufacturing method according to claim 1, 2, 4 and 5, wherein the cut layer assemblies (7) are transported onto a transport medium before they are deposited on the first frame-shaped partial seal (6) and are transported from the first transport medium onto a second transport medium such that the individual layer assemblies (7) are spaced apart from one another.

8. The manufacturing method according to any one of claims 1, 2, 4 and 5, wherein the layer assembly material (4) further comprises a layer assembly carrier film (5), and the cutting of the layer assembly (7) to a predetermined size is performed such that the layer assembly carrier film (5) is not cut in two.

9. 9. The method according to claim 8, wherein the layer assembly carrier film (5) is removed from the layer assembly (7) at an angle of more than 90°, preferably more than 105°, more preferably more than 120°, before the layer assembly (7) is deposited on the first frame-shaped partial seal (6).

10. During the production of the first frame-shaped partial seal (6) in the first sealing material (1), additionally, reference marks are produced in order to align the first partial seal (6), the layer assembly (7) and the second partial seal (8a) relative to one another in the machine direction (M); and / or The method comprises the step of adjusting the width of the first transport medium to the width of the first carrier film (2), and / or the web speed of said first transport medium is between 0.1 m / min and 100 m / min, preferably between 0.5 m / min and 50 m / min, more preferably between 1 m / min and 40 m / min; and / or After compression, the membrane electrode assembly (11) is cooled, and / or the first protective film (3) is provided on the exposed surface side of the first sealing material (1), and / or the second protective film (9) is provided on the exposed surface side of the second sealing material (8), and when the first protective film (3) and / or the second protective film (9) are removed from the first or second frame-shaped partial seal (6), the frame-shaped partial seal (6, 8a) is guided with high positioning accuracy, and / or After compression of the assembly (10), the membrane electrode assembly (11) is cut to its final contour, and / or With or without a final contour cut, the membrane electrode assembly (11) remains on the first carrier film (2) or is singulated as piece goods, separated from the first carrier film (2) and stacked; and / or Each membrane electrode assembly (11) is clearly labeled or marked, said labels being checked for consistency and quality identification, and / or 6. The method according to claim 1, 2, 4 or 5, characterized in that after each processing sequence the quality of the obtained membrane electrode assembly (11) is checked by an inspection system and, in case of component defects, a defect mark is applied, preferably on labelling, so that defective membrane electrode assemblies (11) can be detected and sorted out in subsequent further processing steps.

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