Production apparatus and method for manufacturing a membrane electrode assembly

Abstract

This invention relates to a production apparatus (1) for manufacturing membrane electrode assemblies or equipment frames, having multiple workstations (10, 11, 12, 13, 20) in which successive manufacturing steps are performed. The production apparatus according to the invention is characterized by having a main line (H) and at least one secondary line (N1, N2), the at least one secondary line (N1, N2) branching off from the main line (H) after a central workstation (20) and rejoining the main line (H) after at least one separate workstation (11, 12) in the respective secondary line (N1, N2) and before the central workstation (20). The central workstation (20) includes at least one working section (21) for applying adhesive, and at least some of the separate workstations (10, 11, 12, 13) are configured for bonding and / or positioning additional materials and / or layers (3, 5, 6, 7). The invention also includes a method for manufacturing membrane electrode assemblies or equipment frames using such production apparatus (1).

Description

Technical Field

[0001] This invention relates to a manufacturing apparatus for a membrane electrode assembly or mounting frame according to the preamble of claim 1. The invention also relates to a method for manufacturing such a membrane electrode assembly or mounting frame using this manufacturing apparatus. Background Technology

[0002] Production equipment for manufacturing membrane electrode assemblies is known in principle from the prior art. For example, DE 10 2015 010440 A1 describes a method and apparatus for manufacturing membrane electrode assemblies for fuel cells. Here, different processing stations are arranged sequentially to manufacture a membrane electrode assembly comprising multiple layers and an adhesive disposed between them in a more or less continuous manufacturing process. DE 10 2016 000 974 A1 also relates to this subject and proposes an alternative apparatus, but the structure of which is basically similar, namely comprising sequentially arranged workstations, each performing the same working step.

[0003] The structure of this production equipment is correspondingly complex and expensive because it requires multiple different workstations within the structure.

[0004] Regarding other prior art, reference may also be made to so-called membrane electrode assemblies with mounting frames, which are known, for example, from DE 102015 010 419 A1. These membrane electrode assemblies follow essentially the same manufacturing basis in terms of production.

[0005] For further prior art, see also DE 10 2015 010 422 A1 and DE 10 2016 006225 A1. These documents relate to the printing of adhesives, particularly the digital printing of adhesives for manufacturing membrane electrode assemblies, wherein the adhesive is applied to different layers of the membrane electrode assembly being bonded together or fitted into a frame, or also to the previously applied adhesive layer itself. Summary of the Invention

[0006] The present invention aims to provide an improved production apparatus for manufacturing membrane electrode assemblies or equipment frames, and a method for manufacturing membrane electrode assemblies using such production apparatus.

[0007] According to the invention, this objective is achieved by a production apparatus having the features of claim 1, and particularly the feature portion of claim 1. Claim 8 provides a method for manufacturing a membrane electrode assembly or a membrane electrode assembly frame using such an apparatus. In both cases, preferred and extended designs are described in their respective dependent claims.

[0008] Production equipment for manufacturing membrane electrode assemblies (MEAs) or membrane electrode frames (MEFAs) similar to the production equipment described in the prior art mentioned at the beginning includes multiple workstations / stations in which successive manufacturing steps are performed. The production equipment according to the invention is now configured to have a main line and at least one sub-line, which branches off from the main line after a central workstation in the main line and rejoins the main line after at least one separate workstation in the respective sub-line, and rejoins the main line before the central workstation. This configuration enables the processing of semi-finished products conveyed via the main line in the central workstation, then diverting them to one of the sub-lines, where the previous structure is further processed, and then guiding them back to the main line for further processing there, wherein these two processing steps in the central workstation can, in principle, be different. The production equipment according to the invention here includes at least one working section for applying adhesives as a central workstation. Therefore, adhesive application can preferably always be carried out in a central workstation within the production equipment, while other materials or layers are joined and / or positioned / placed in separate workstations so that they can be coated again in the central workstation using additional adhesive layers.

[0009] This reusability of the central workstation used for applying adhesives significantly reduces the required investment in production equipment, as the reusability of specific equipment sections is highly advantageous. This is particularly relevant for adhesive application, for example, by printing methods, which would require a relatively complex and expensive central workstation, especially if it is subsequently equipped with a measuring station for inspecting the application (which could be the case, according to an advantageous extension of the concept).

[0010] Therefore, in the production equipment according to the invention, at least one adhesive is always applied at the central workstation. However, the requirements for adhesive application may vary depending on the state of the semi-finished product as it arrives at the central workstation, and thus, depending on whether the adhesive must be applied to the first, second, or third layer, etc., for example, the adhesive must be applied in a different application pattern.

[0011] Joining in separate workstations typically involves applying an additional layer to a pre-fabricated semi-finished product, which has previously been coated with adhesive at a desired location in a central workstation, specifically for securing the applied additional layer. Joining can then be performed, for example, by a robot, preferably in a stationary state or, if necessary, during movement of the workpiece carrier for the semi-finished product. In a stationary state, positioning or joining can also be performed via a linear axis. During movement, the corresponding joining process can be achieved, for example, by vacuum rollers or by two overlapping moving workpiece carriers.

[0012] According to a particularly advantageous extension of the production equipment according to the invention, the adhesive can be applied by printing, in particular by digital printing. Different printing methods can be used, such as screen printing, which is performed in the static state of the semi-finished product and, when needed, with different screens corresponding to the desired pattern. The screens can be stored in a cassette. Alternatively, letterpress or gravure printing methods with corresponding punches are conceivable, which, similar to screen printing, require different stencil punches, but have the advantage of being able to be performed during the movement of the semi-finished product. However, a digital printing method, which can also be performed during the movement of the semi-finished product, is particularly advantageous and efficient. Here, the desired pattern for the corresponding process step can be selected very easily using different stored printing stencils, and this can be achieved quickly and easily via digital printing. Possible adjustments to the pattern can also be performed very easily and efficiently.

[0013] A particularly advantageous design of the production equipment according to the invention further specifies that at least one additional separate workstation is provided in the main line before the secondary line enters or after the branching. That is, at least one separate workstation can be provided at the beginning and end of the main line, thereby enabling up to four different workstations, for example, using two secondary lines each containing one separate workstation. In these workstations, materials can be joined accordingly, wherein, according to a very advantageous extension of the production equipment according to the invention, at least one of the separate workstations includes a working section for cutting materials and / or manufactured semi-finished or finished products. The separate workstations can in particular be the first and last separate workstations, which, according to the design of the production equipment just described, can be arranged in the main line, for example, before the secondary line enters and after the branching. In principle, cutting can be performed in different ways, for example by means of a laser. Shape cutting by means of a stamping profile or drawing cutting machine is also conceivable in principle. Especially in the final workstation, it is conceivable to use an upright tool to trim the sides of each individual component and, for example, to use a movable tool to trim the length, as is known in principle from production using multiple workstations in succession.

[0014] According to a highly advantageous extension of the production equipment according to the invention, in addition to the work section for applying the adhesive, the central workstation may also include a work section for activating or curing the adhesive. Depending on the adhesive material used, this curing or activation can be carried out, for example, by UV radiation generated by means of a UV-LED or a UV medium-pressure lamp. Curing / activation by thermal radiation, electronic radiation, etc., is also conceivable.

[0015] According to another highly advantageous design of the production equipment according to the invention, the central workstation further includes a work section for measuring, for example, the applied adhesive. If problems arise during adhesive application, intervention can be made at the central workstation after the measurement work section, if necessary, to stop or correct further manufacturing of the semi-finished product or membrane electrode assembly or membrane electrode assembly of the equipment frame, thereby minimizing the scrap rate. Other values ​​of the adhesive or other applied materials, such as their shape, position, etc., can also be measured at the measuring station when needed.

[0016] The method according to the invention for manufacturing membrane electrode assemblies or membrane electrode assemblies with mounting frames using production equipment in one of the aforementioned embodiments specifies that a first material layer, in particular a first layer of gas diffusion layer, is input through a main line. An adhesive is then applied to the first layer according to a first predetermined pattern at a central workstation. The first layer with adhesive is then passed through / through a first sub-line, in which a second layer is precisely placed at a separate workstation. The bonded layers, such as a gas diffusion layer bonded to a frame, are then passed through the central workstation again through the main line. At the central workstation, an adhesive is applied to the second layer according to a second predetermined pattern. This process is then repeated until all sub-lines have been passed through at least once. Therefore, different layers, such as gas diffusion layers, frames, catalytically coated membranes, and additional gas diffusion layers, can be used to simply and efficiently manufacture membrane electrode assemblies or membrane electrode assemblies with mounting frames, as exemplarily mentioned herein, by passing through the central workstation for applying adhesive multiple times and correspondingly through separate workstations for applying the next layer.

[0017] According to a highly advantageous design of the method according to the invention, the pattern required precisely according to the processing state of the layer or semi-finished product can be digitally printed to adapt the pattern of the corresponding layer to the application of adhesive, especially during the movement of the semi-finished product composed of layers constructed to date on the main line. Digital printing here allows for the very simple and efficient selection of the respective required patterns. For example, selection can be based on the process cycle in the production equipment, but it can also be achieved, for example, by evaluating the corresponding semi-finished products entering discrete workstations using an optical system to identify which pattern must be applied.

[0018] A particularly advantageous extension of the method according to the invention is provided herein, wherein the cycle time for inputting the first layer to the main line is controlled such that at least one intermediate product of the membrane electrode assembly or the membrane electrode assembly of the mounting frame is processed simultaneously in each line (i.e., the main line and the sub-line) using different processing steps. Therefore, the production equipment according to the invention need not be used in such a way that a semi-finished product is moved through the equipment until it is completed before inputting the next first layer. Instead, the cycle time can be controlled such that, for example, the first layer enters a separate workstation through the main line to apply adhesive according to a first pattern, while the bonding task is performed in the existing sub-line, and then enters a separate workstation in the next cycle after the adhesive has been applied to the first layer, thereby keeping as many workstations of the production equipment as possible continuously busy / operating, so that short production throughput / cycle times can be achieved in the manufacture of membrane electrode assemblies or membrane electrode assemblies of mounting frames. Attached Figure Description

[0019] Further advantageous designs for the production equipment and the method for operating the production equipment according to the invention also arise from embodiments, which are described in more detail below with reference to the accompanying drawings. Herein:

[0020] Figure 1 A schematic structure of a possible embodiment of the production equipment according to the present invention is shown;

[0021] Figures 2 to 8 Different processing states of the semi-finished membrane electrode assembly of the equipment frame to be manufactured are shown. Detailed Implementation

[0022] exist Figure 1 The diagram shows the production equipment, represented by 1. This equipment is used to manufacture membrane electrode assemblies (MEFAs), or in this case, specifically MEFA assemblies 2 with frames. According to the abbreviation, the membrane electrode assembly is also called MEFA 2. This manufactured MEFA 2... Figure 8 The diagram schematically illustrates this. Viewed from bottom to top, MEFA 2 comprises a first layer, indicated by 3, the so-called gas diffusion layer or GDL. The frame, indicated by 5, is then bonded to it using adhesive 4, indicated by cross-shading. Subsequently, the actual membrane 6 for the fuel cell is bonded to the frame 5 using another adhesive 4; this membrane is typically constructed as a so-called CCM (catalyst-coated membrane) or catalytically coated membrane 6. Finally, the final layer, indicated by 7, is applied using another adhesive 4; this layer is also constructed as a gas diffusion layer or GDL.

[0023] Instead of applying the electrode to membrane 6, it is conceivable to apply the electrode to the GDL. This results in a so-called gas diffusion electrode (GDE). Instead of the described layer structure consisting of GDL 7, frame 5, CCM 6, and frame 5, the structure can also be composed of GDE, frame 5, CCM 6, and frame 5. The following embodiments are also applicable to this structure.

[0024] The structure is correspondingly in Figure 1 It is manufactured in production equipment 1 shown. In the discrete workstation indicated by 10, the first layer 3, namely the gas diffusion layer, is applied to the workpiece carrier indicated by 8. This can be correspondingly... Figure 2 As shown in the diagram, the first layer 3, positioned on the workpiece carrier 8, then enters the central workstation 20 of the production equipment 1 along the main line H. In the embodiment shown here, the central workstation 20 includes three work sections. In the direction of material flow, the first is the work section indicated by 21, which applies the adhesive 4 to the corresponding layer. Figure 3 The process steps shown are as follows: the adhesive 4 is applied to the first layer 3. Preferably, the adhesive 4 is applied according to a first predetermined pattern via digital printing while the workpiece carrier 8 moves through the central workstation 20. In the adjacent work section 22, the adhesive 4 is cured or activated, for example, by UV radiation applied by a UV-LED. Another optional work section 23 includes measuring the first layer 3 and, in particular, the applied adhesive 4.

[0025] According to the arrow indicated by I, such a prefabricated product or semi-finished product, formed from a first layer 3 with applied adhesive 4, is then transferred via a first sub-line N1 to another separate workstation indicated by 11. In this separate workstation, as... Figure 4 As shown in the diagram, frame 5 is applied and bonded to the first layer 3 by the already applied adhesive 4. As indicated by the arrow marked II, the completed semi-finished product then re-enters the central workstation 20, where, as... Figure 5 As shown in the diagram, additional adhesive 4 is applied this time onto the existing adhesive 4 and frame 5. The resulting semi-finished product is then transferred, via the second sub-line N2 of production equipment 1 (indicated by arrow III), to another separate workstation (indicated by 12). In this other separate workstation, a catalytically coated film 6 is applied, as shown... Figure 6 As shown in the diagram. Here, after the catalytically coated membrane 6 is applied, the semi-finished product is guided back to the central workstation 20 according to arrow IV, where, as from... Figure 7As can be seen from the diagram, adhesive 4 is reapplied, here applied to the catalytically coated layer 6, and partially applied to the previously applied adhesive 4. After passing through the central workstation 20 again, the semi-finished product is then transferred along the main line H as indicated by arrow V to another discrete workstation 13, where the final gas diffusion layer 7 is applied in the region to complete the structure of the membrane electrode assembly 2 with the equipment frame.

[0026] Furthermore, this structure can be tailored to its final dimensions, for example, in the area of ​​the discrete workstation 13 mentioned last, by stamping, laser cutting, drawing cutter, or also by a side-mounted cutter and a freely vibrating cutter, which cuts the completed membrane electrode assembly 2 of the equipment frame to the correct length. Finally, the membrane electrode assembly 2 of the equipment frame is obtained in... Figure 8 The structure already described is shown in the schematic diagram.

[0027] Of course, instead of only one semi-finished product passing through the production equipment simultaneously as previously described, another first layer 3 can be positioned on another workpiece carrier 8 while the adhesive 4 is applied to the first layer in the central workstation 20, and the frame 5 can be applied to other previously adhesive-coated semi-finished products, for example, in a separate workstation 11. Similarly, a semi-finished product can also be present in a separate workstation 12, on which the film 6 is applied. In short, it is only necessary to control the production cycle so that no collisions or congestion of semi-finished products occur before the respective workstations 20, 10, 11, 12, and 13. However, when the cycle is appropriate, it is possible that exactly one semi-finished product is processed on the workpiece carrier 8 in all workstations, not only in the separate workstations 10 to 13, but also in the central workstation 20, so that production can still proceed as rapidly as in the case of continuous production with multiple successive workstations and correspondingly three discrete workstations whose structure corresponds to the central workstation 20.

[0028] Here, this embodiment's structure should be understood in its manner as purely exemplary. The order can also be reversed, merely to illustrate one possible variation. Similarly, the arrangement of the individual sub-lines can be adjusted to allow access to all modules, etc.

Claims

1. A production apparatus (1) for manufacturing membrane electrode assemblies or framed membrane electrode assemblies (2), the production apparatus having multiple workstations (10, 11, 12, 13, 20) in which successive manufacturing steps are performed, the multiple workstations including a central workstation (20) and multiple separate workstations (10, 11, 12, 13). Its features are, There is a main line (H) and at least one sub-line (N1, N2), wherein at least one sub-line (N1, N2) branches off from the main line (H) after a central workstation (20) and enters the main line (H) after at least one (11, 12) of the plurality of discrete workstations (10, 11, 12, 13) in the respective sub-line (N1, N2) and before the central workstation (20), wherein the central workstation (20) includes at least one working section (21) for applying adhesive, at least some of the plurality of discrete workstations (10, 11, 12, 13) are configured to apply and / or bond additional layers (3, 5, 6, 7), wherein the at least one working section (21) is configured to apply adhesive in different application patterns, and the production equipment (1) is configured to evaluate the incoming semi-finished product by means of an optical system to identify which of the different application patterns must be applied.

2. The production plant (1) according to claim 1, characterized in that, The working section (21) for applying adhesive includes equipment for printing adhesive (4).

3. The production plant (1) according to claim 2, characterized in that, The device used for printing adhesive (4) is configured as a digital printer.

4. The production plant (1) according to claim 1, 2 or 3, characterized in that, In the main line (H), before or after at least one sub-line (N1, N2) enters, there is at least one additional separate workstation (10, 13) among the plurality of separate workstations (10, 11, 12, 13).

5. The production apparatus (1 ) according to any one of claims 1 to 3, characterized in that At least one of the plurality of separate workstations (10, 11, 12, 13) includes a work section for cutting the manufactured semi-finished product or the manufactured membrane electrode assembly or the framed membrane electrode assembly (2).

6. The production apparatus (1) according to any one of claims 1 to 3, characterized in that The central workstation (20) also includes a work section (22) for activating / curing the adhesive (4).

7. The production equipment (1) according to any one of claims 1 to 3, characterized in that, The central workstation (20) also includes a work section (23) for measuring at least the applied adhesive (4).

8. A method for manufacturing a membrane electrode assembly or a framed membrane electrode assembly using the production equipment (1) according to any one of claims 1 to 7, Its features are, The first layer (3) is input via the main line (H), and then in the central workstation (20), the adhesive is applied to the first layer (3) according to a first predetermined pattern. The first layer (3) with adhesive (4) is then passed through the first sub-line (N1), in which the second layer (5) is precisely bonded in the separate workstation (11). The bonded layers (3, 5) are then passed through the central workstation (20) again via the main line (H), in which the adhesive is applied to the second layer (5) according to a second predetermined pattern. The process is then repeated until all sub-lines (N1, N2) have been passed through at least once. The incoming semi-finished product is evaluated by an optical system to identify which of the different application patterns must be applied as the second predetermined pattern.

9. The method according to claim 8, characterized in that, During the movement of the semi-finished product along the main line (H), an adhesive is applied to the pattern that is exactly required according to the processing state of the semi-finished product by digital printing, so as to fit the pattern of the corresponding layer (3, 5, 6).

10. The method according to claim 8 or 9, characterized in that, The control inputs the first layer (3) into the main line (H) so that at least one intermediate product is processed simultaneously in each line (H, N1, N2) using different processing steps.

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