Method for manufacturing a membrane electrode assembly

Abstract

The present application provides a method for manufacturing a membrane electrode assembly (MEA). In particular, a first sub-gasket sheet and a second sub-gasket sheet are continuously supplied, and an electrode membrane sheet in which a gap is formed is discontinuously supplied, thereby reducing the amount of use of an electrolyte membrane. Accordingly, the electrolyte membrane protrudes in a minimum length between the sub-gasket sheets, and the electrolyte membrane is bonded to the sub-gasket together with an electrode catalyst layer.

Description

Technical Field

[0001] The present invention relates to a method for manufacturing membrane electrode assemblies, and more specifically, to a method for manufacturing membrane electrode assemblies that reduces the use of polymer electrolyte membranes. Background Technology

[0002] Fuel cells generate electricity through an electrochemical reaction between hydrogen and oxygen. These fuel cells can receive chemical reactants externally without requiring a separate charging process, thus enabling continuous power generation. Fuel cells can be configured such that separators (or bipolar plates) are arranged on either side of a membrane electrode assembly (MEA). These fuel cells are arranged sequentially to form a fuel cell stack.

[0003] Figure 1 This is a schematic cross-sectional view illustrating an example of a conventional membrane electrode assembly according to the prior art. (Refer to...) Figure 1 An exemplary membrane electrode assembly 1, corresponding to the main components of a fuel cell, includes an electrode catalyst layer 5 disposed on two surfaces of an electrolyte membrane 3, on which protons move to form an anode and a cathode. Furthermore, the membrane electrode assembly 1 includes a sub-shield 7 that protects the electrode catalyst layer 5 and the electrolyte membrane 3 and ensures the assemblability of the fuel cell.

[0004] As a manufacturing process for the above-mentioned membrane electrode assembly 1, firstly, an electrode membrane sheet 6 is manufactured using a pressure transfer method. In this method, an electrolyte membrane 3 wound into a roll is unwound, and an electrode catalyst layer 5 is continuously transferred to two surfaces of the electrolyte membrane 3, thereby spacing them apart by a specific distance.

[0005] Subsequently, as a post-processing step, a roll-to-roll method is used to manufacture the membrane electrode assembly sheet, wherein the rolled-up electrode membrane sheet 6 is unwound and conveyed, the rolled-up sub-pads 7 are unwound and arranged on both surfaces of the electrode membrane sheet 6, and then the electrode membrane sheet 6 with the sub-pads 7 on its two surfaces is passed between hot rollers to bond the sub-pads 7 to the two surfaces of the electrode membrane sheet 6.

[0006] Specifically, a sub-pad 7, in a state where electrode windows (used to open the electrode catalyst layer 5) and manifold windows are formed by cutting, can be supplied to both surfaces of the electrode membrane sheet 6, and then bonded to the surface of the electrode membrane sheet 6. Following this process, the membrane electrode assembly sheet can be manufactured by unwinding the rolled-up sheet and then cutting it into units including the electrode catalyst layer 5. Figure 1 The membrane electrode assembly 1 shown.

[0007] In the conventional membrane electrode assembly 1 manufactured by the above method, an electrode membrane sheet 6 is prepared in which an electrode catalyst layer 5 is continuously formed on both sides of an electrolyte membrane 3, and sub-pads 7 are bonded to both sides of the electrode membrane sheet 6, with the electrolyte membrane 3 arranged in all areas between the sub-pads 7.

[0008] The development of the sub-pad 7 used in the membrane electrode assembly 1 is only intended to prevent leakage of reactive gases or is related to battery output performance, and the impact on the mechanical durability of the membrane electrode assembly 1 and the electrolyte membrane 3 is unknown. Therefore, in a conventional membrane electrode assembly 1, the sub-pad 7 is bonded to the outer region of the electrode catalyst layer 5, i.e., the non-power generation region, and the electrolyte membrane 3 is inserted between the sub-pad 7 and the non-power generation region. Thus, the electrolyte membrane 3 exists in the non-power generation region.

[0009] Therefore, in the non-power generation area of ​​a conventional membrane electrode assembly 1, there is an electrolyte membrane 3 that only supports the sub-pad 7, which wastes relatively expensive electrolyte membrane material and increases the manufacturing cost of the membrane electrode assembly 1.

[0010] The above description is provided to enhance understanding of the background of the invention and should not be construed as conventional technology known to those skilled in the art. Summary of the Invention

[0011] The present invention provides a method for manufacturing a membrane electrode assembly, wherein a first sub-pad sheet and a second sub-pad sheet are continuously supplied (using a roll-to-roll method), and an electrode membrane sheet is discontinuously supplied (using a stop-and-go method) with gaps formed in the electrode membrane sheet to reduce the amount of electrode membrane sheet used, thereby reducing the use of electrolyte membrane.

[0012] In one aspect, the present invention provides a method for manufacturing a membrane electrode assembly (MEA), the method comprising: unwinding and supplying a first sub-pad sheet and a second sub-pad sheet wound into rolls; continuously forming electrode windows in the supplied first sub-pad sheet and second sub-pad sheet using a first sub-pad cutter and a second sub-pad cutter, such that the electrode windows are spaced apart from each other by a predetermined interval; continuously supplying the first sub-pad sheet and second sub-pad sheet with the continuously formed electrode windows to a first sub-pad sheet bonding roller and a second sub-pad sheet bonding roller; unwinding and supplying an electrode membrane sheet wound into rolls; continuously forming gaps in the supplied electrode membrane sheet using an electrode membrane cutter, such that the gaps are spaced apart from each other by a predetermined interval; and supplying the electrode membrane sheet with the gaps to the electrode membrane sheet bonding roller.

[0013] Furthermore, the method may include: a first bonding, wherein a supplied first sub-pad sheet and a supplied electrode film sheet are bonded by passing a first sub-pad sheet bonding roller and an electrode film sheet between the first sub-pad sheet bonding roller and the electrode film sheet bonding roller; and a second bonding, wherein a second component supplied from the first sub-pad sheet bonding roller after the first bonding is bonded to a second sub-pad sheet supplied from the second sub-pad sheet bonding roller, the second bonding being performed by passing the second component and the second sub-pad sheet between the first sub-pad sheet bonding roller and the second sub-pad sheet bonding roller.

[0014] In one exemplary embodiment, the method may further include a third adhesion, bonding a second component supplied from a first sub-pad sheet adhesion roller and a second sub-pad sheet adhesion roller after a second adhesion, the third adhesion being performed by passing the second component between step-preventive reinforced adhesion rollers. Furthermore, the electrode film sheet may include: an electrolyte membrane; an electrode catalyst layer formed on a central portion of one surface and another surface of the electrolyte membrane; and a protective film disposed on the outer surface of one of the electrode catalyst layers.

[0015] The protective film can be removed after the first adhesion. The step of continuously forming gaps may include: separating portions of the electrolyte membrane of the electrode membrane sheet to form gaps by performing a punching process using a punching roller included in an electrode membrane cutter; removing the separated portions of the electrolyte membrane; and collecting the removed portions of the electrolyte membrane.

[0016] Furthermore, the depth of the perforated plate included in the perforating roller can be approximately 15–250 μm, and the size of the gap can be approximately 2–34 mm. Before the first bonding, gaps can be formed in the electrode film sheet, and the electrode film sheet with the gaps is supplied to the electrode film sheet bonding roller via a pair of buffer rollers.

[0017] In an exemplary embodiment, when supplying the electrode film sheet to the electrode film sheet bonding roller, the electrode film sheet can be supplied discontinuously only when the first bonding is performed while the electrode film sheet is in contact with the electrode window of the first sub-pad sheet. The electrode film sheet bonding roller can be operated such that it performs rotational motion at the contact point where the electrode film sheet contacts the first sub-pad sheet bonding roller, and then performs linear motion at the point where the electrode film sheet does not contact the first sub-pad sheet bonding roller.

[0018] Furthermore, the electrode film bonding roller and the first sub-pad bonding roller can be arranged such that the angle formed by the straight line including the contact point undergoing rotational motion and the straight line on the path of the linear motion is less than 90 degrees. The electrode film bonding roller can be lighter than the first sub-pad bonding roller. Attached Figure Description

[0019] The above and other features of the invention will now be described in detail with reference to certain exemplary embodiments shown in the accompanying drawings, which are given by way of example only below and therefore do not limit the invention, wherein:

[0020] Figure 1 This is a schematic cross-sectional view illustrating an example of a conventional membrane electrode assembly (MEA) according to related technologies;

[0021] Figure 2 This is a schematic diagram illustrating the construction of a membrane electrode assembly (MEA) manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention;

[0022] Figures 3A to 3F This is a schematic cross-sectional view of the structure included in portions A to F along the flow direction during the manufacturing process of a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention.

[0023] Figure 4A This is a schematic cross-sectional view illustrating an electrode film cutter included in a membrane electrode assembly (MEA) manufacturing apparatus according to an exemplary embodiment of the present invention;

[0024] Figure 4B This is a schematic cross-sectional view of the perforated plate of the perforating roller included in an electrode film cutter according to an exemplary embodiment of the present invention.

[0025] Figures 5A to 5D This is an enlarged structural diagram illustrating a first bonding process according to an exemplary embodiment of the present invention, wherein an electrode film sheet supplied from an electrode film sheet bonding roller and a first sub-pad sheet supplied from a first sub-pad sheet bonding roller are bonded together.

[0026] Figure 6 This is an enlarged structural view showing the bonding position between the electrode film sheet bonding roller and the first sub-pad sheet bonding roller, illustrating an exemplary embodiment of the present invention;

[0027] Figure 7A This is a cross-sectional view illustrating a first sub-gasket sheet bonding roller and a second sub-gasket sheet bonding roller according to an exemplary embodiment of the present invention;

[0028] Figure 7B This is a front view of the second component according to an exemplary embodiment of the present invention;

[0029] Figure 7CThis is a cross-sectional view showing an anti-step reinforcing adhesive roller pressing a step portion in a second component according to an exemplary embodiment of the present invention, the step portion being formed due to the electrode film sheet being shorter than the sub-pad sheet;

[0030] Figure 7D This is a front view of a membrane electrode assembly (MEA) included in part G according to an exemplary embodiment of the present invention;

[0031] Figure 8A and Figure 8B This is a schematic diagram illustrating the structure of a buffer roller additionally included in a manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention;

[0032] Figure 9 This is a schematic diagram illustrating the structure of a vacuum conveyor additionally included in the manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention.

[0033] Figure 10 This is a graph showing the results of performance (durability) evaluations of an MEA manufactured under variable pressure conditions in an embodiment of the invention and an MEA manufactured in a comparative example; and

[0034] Figure 11 This is a graph showing the results of performance (durability) evaluations of MEAs manufactured under normal conditions in the examples of the present invention and MEAs manufactured in the comparative examples.

[0035] It should be understood that the accompanying drawings are not drawn to scale, but rather are illustrative simplifications to present various features to illustrate the basic principles of the invention. Specific design features of the invention disclosed herein (including, for example, specific dimensions, orientations, positions, and shapes) will be determined in part by the specific environment in which they are intended to be applied and used. In the accompanying drawings, the same or equivalent parts are indexed with the same reference numerals. Detailed Implementation

[0036] It should be understood that the term “vehicle” or “of a vehicle” or other similar terms used herein generally include motor vehicles, such as passenger vehicles including sport utility vehicles (SUVs), buses, trucks, various commercial vehicles, vessels including various boats and ships, aircraft, etc., and also include hybrid vehicles, electric vehicles, plug-in hybrid electric vehicles, hydrogen-powered vehicles, and other alternative fuel vehicles (e.g., fuels derived from non-fossil energy sources).

[0037] Although the exemplary embodiments are described as using multiple units to perform the exemplary process, it is understood that the exemplary process may also be performed by one or more modules. Furthermore, the term "controller / control unit" is understood to refer to a hardware device including a memory and a processor. The memory is configured to store modules, and the processor is specifically configured to execute said modules to perform one or more processes described further below.

[0038] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “an,” “a,” and “the” are intended to equally include the plural forms unless the context explicitly states otherwise. It will also be understood that when the terms “comprising” and / or “including” are used in this specification, they indicate the presence of the stated feature, value, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, values, steps, operations, elements, components, and / or groups thereof. As used herein, the term “and / or” includes any and all combinations of one or more of the related enumerations.

[0039] Unless otherwise stated or obvious from the context, the term “about” as used herein is understood to mean within the normal tolerance range in the field, such as within an average of 2 standard deviations. “About” can be understood as within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.1%, 0.05%, or 0.01% of the specified value. Unless the context otherwise requires, the term “approximately” modifies all numerical values ​​provided herein.

[0040] Various exemplary embodiments of the invention will be shown in detail below, examples of which are illustrated in the accompanying drawings and described below. Although the invention will be described in conjunction with exemplary embodiments, it should be understood that this specification is not intended to limit the invention to the exemplary embodiments. Rather, the invention is intended to cover not only these exemplary embodiments, but also various alternatives, modifications, equivalents, and other exemplary embodiments within the spirit and scope of the invention as defined by the appended claims.

[0041] In the following description of exemplary embodiments, the same elements are represented by the same reference numerals even if they are shown in different figures. In the figures, the dimensions of the structures are enlarged compared to the actual dimensions for clarity. In the following description of embodiments, terms such as "first," "second," etc., may be used to describe various elements, but are not limiting. These terms are only used to distinguish one element from others. For example, within the spirit and scope of the invention, a first element may be named a second element, and similarly, a second element may be named a first element. Plural expressions may be included unless they have a distinctly different meaning in the context.

[0042] In the following description of exemplary embodiments, it will be understood that when a component such as a layer, membrane, region, or plate is referred to as being “on” another component, that component may be located “directly” on the other component, or other components may be inserted between the two components. Similarly, it will be understood that when a component such as a layer, membrane, region, or plate is referred to as being “below” another component, that component may be located “directly” below the other component, or other components may be inserted between the two components.

[0043] In the following description of exemplary embodiments, it will be understood that when a range of a variable is stated, the variable includes all values ​​within the range, including the endpoints specified by the range. For example, it will be understood that the range "5 to 10" includes not only the values ​​5, 6, 7, 8, 9, and 10, but also any subranges, such as subranges of 6 to 10, subranges of 7 to 10, subranges of 6 to 9, subranges of 7 to 9, etc., and any values ​​between integers valid within the specified range, such as 5.5, 6.5, 7.5, 5.5 to 8.5, 6.5 to 9, etc. Furthermore, for example, it will be understood that the range of “10% to 30%” includes not only all integers of the values ​​10%, 11%, 12%, 13%, ... 30%, but also any subranges, such as the subrange of 10% to 15%, the subrange of 12% to 18%, the subrange of 20% to 30%, etc., as well as any values ​​between integers valid within the specified range, such as 10.5%, 15.5%, 25.5%, etc.

[0044] Figure 2 This is a schematic diagram illustrating the construction of a membrane electrode assembly (MEA) manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention. It is noteworthy that this manufacturing method can be executed by a controller operating various mechanical characteristics of the apparatus. (Refer to...) Figure 2The manufacturing apparatus 100 used in the method for manufacturing a membrane electrode assembly (MEA) may include a first sub-pad sheet unwinder 110a, a second sub-pad sheet unwinder 110b, a first sub-pad sheet cutter 120a, a second sub-pad sheet cutter 120b, an electrode film sheet unwinder 130, an electrode film cutter 140, an electrode film sheet bonding roller 150, a first sub-pad sheet bonding roller 160a, a second sub-pad sheet bonding roller 160b, and a step-preventive reinforcing bonding roller 170.

[0045] The first sub-gasket sheet unwinder 110a, the second sub-gasket sheet unwinder 110b, the first sub-gasket cutter 120a, and the second sub-gasket cutter 120b can operate at the same speed to continuously perform the process. The first sub-gasket sheet 10a can be formed by attaching the first sub-gasket 11a to the surface of the protective film 12a. Figure 3A The detailed structure of the first sub-gasket sheet 10a in part A is shown. The first sub-gasket sheet 10a can be wound into a roll on the first sub-gasket sheet unwinder 110a, and the first sub-gasket sheet unwinder 110a can be configured to unwind and continuously supply the first sub-gasket sheet 10a in the flow direction of the process.

[0046] The first sub-pad cutter 120a can be arranged on one side of the first sub-pad sheet unwinder 110a along the flow direction of the process, and electrode windows 13a are continuously formed in the first sub-pad sheet 10a so that the electrode windows 13a are spaced apart from each other by a predetermined interval. In particular, referring to Figure 2 The protective film 12a included in the first pad 10a can be removed by the first sub-pad cutter 120a. The first sub-pad sheet 10a, in which electrode windows 13a are continuously formed, can be supplied to the first sub-pad sheet bonding roller 160a. Figure 3B The image shows the first sub-gasket sheet 10a supplied to the first sub-gasket sheet adhesive roller 160a in section B.

[0047] The second sub-gasket sheet 10b can be formed by attaching the second sub-gasket sheet 11b to the surface of the protective film 12b. Figure 3A The detailed structure of the second sub-gasket sheet 10b in part A is shown. The second sub-gasket sheet 10b can be wound into a roll on the second sub-gasket sheet unwinder 110b, and the second sub-gasket sheet unwinder 110b can be configured to unwind and continuously supply the second sub-gasket sheet 10b in the flow direction of the process.

[0048] The second sub-pad cutter 120b can be arranged on one side of the second sub-pad sheet unwinder 110b along the flow direction of the process, and electrode windows 13b are continuously formed in the second sub-pad sheet 10b such that the electrode windows 13b are spaced apart from each other by a predetermined interval. In particular, referring to Figure 2 The protective film 12b included in the second pad 10b can be removed by the second pad cutter 120b. The second pad sheet 10b, in which electrode windows 13b are continuously formed, can be supplied to the second pad sheet bonding roller 160b. Figure 3B The image shows the second sub-gasket sheet 10b supplied to the second sub-gasket sheet adhesive roller 160b in section B.

[0049] The electrode membrane sheet 20 may include an electrolyte membrane 21, an electrode catalyst layer 22, and a protective film 23; the electrode catalyst layer 22 is formed on a central portion of a first surface and a second surface of the electrolyte membrane 21; the protective film 23 is disposed on an outer surface of one of the electrode catalyst layers 22. Figure 3C The detailed structure of the electrode film sheet 20 in part C is shown. The electrode film sheet 20 can be wound into a roll on the electrode film sheet unwinder 130, and the electrode film sheet unwinder 130 can be configured to unwind in the flow direction of the process and supply the electrode film sheet 20 discontinuously (using a stop-and-go method). The electrode film cutter 140 can be arranged on one side of the electrode film sheet unwinder 130 along the flow direction of the process, and can be configured to continuously form gaps 24 in the electrode film sheet 20, such that the gaps 24 are spaced apart from each other at predetermined intervals.

[0050] Figure 4A This is a schematic cross-sectional view illustrating the detailed process of an electrode film cutter 140 continuously forming gaps 24 in a membrane electrode assembly (MEA) manufacturing apparatus according to an exemplary embodiment of the invention. (Refer to...) Figure 4A The electrode film cutter 140 may include a punching roller 141, a blower 142, and a collector 143: the punching roller 141 contacts the electrode film sheet 20; the blower 142 is formed below the punching roller 141; and the collector 143 is arranged outside the blower 142 and below the punching roller 141.

[0051] Specifically, the formation of the gap 24 may include a punching process via a punching roller 141 included in the electrode film cutter 140, separating a portion of the electrolyte membrane 21 by suction to form the gap 24, removing the separated portion of the electrolyte membrane 21 using a blower 142, and collecting the removed portion of the electrolyte membrane 21 in a collector 143.

[0052] Figure 4BThis is a schematic cross-sectional view showing the punch plate 141a included in the punching roller 141. (Refer to...) Figure 4B The perforating plate 141a included in the perforating roller 141 can have any depth corresponding to the thickness of the electrolyte membrane 21 being perforated, but is not limited thereto. Specifically, the perforating plate 141a can have a depth ranging from the thickness of the electrolyte membrane 21 to the sum of the thickness of the electrolyte membrane 21 and the thickness of the protective film 23. More specifically, the perforating plate 141a has a minimum depth corresponding to the thickness of the electrolyte membrane 21 + 3 μm to ensure perforation stability, and a maximum depth corresponding to the sum of the thickness of the electrolyte membrane 21 and the thickness of the protective film 23 - 3 μm to ensure transfer stability and prevent cutting. In particular, the thickness of the electrolyte membrane 21 can be approximately 5-50 μm. When the thickness of the electrolyte membrane 21 is less than approximately 5 μm, durability may deteriorate or be reduced, and when the thickness of the electrolyte membrane 21 exceeds approximately 50 μm, the performance of the electrolyte membrane 21 may be unsatisfactory.

[0053] Furthermore, the thickness of the protective film 23 can be approximately 10-200 μm. When the thickness of the protective film 23 is less than approximately 10 μm, stretching of the protective film 23 due to tension and stretching of the protective film 23 due to punching tolerances may cause processing difficulties. Furthermore, when the thickness of the protective film 23 exceeds approximately 200 μm, equipment durability and processability may decrease due to the increased weight of the protective film 23 to be wound. Therefore, the depth of the punch plate 141a included in the punching roller 141 can be approximately 15-250 μm, particularly approximately 18-247 μm. When the depth of the punch plate 141a is less than approximately 15 μm, processability and product durability may decrease. Furthermore, when the depth of the punch plate 141a exceeds approximately 250 μm, processability may decrease and the material used for the punch plate 141a may be overused.

[0054] The electrode film sheet bonding roller 150 can be arranged on one side of the electrode film cutter 140 along the flow direction of the process, and the electrode film sheet 20 with the gap 24 formed therein can be continuously or discontinuously supplied from the electrode film cutter 140 to the electrode film sheet bonding roller 150. In particular, the electrode film sheet 20 can be discontinuously supplied to the electrode film sheet bonding roller 150 based on the first bonding operation described below.

[0055] Specifically, the electrode film 20 can only be discontinuously supplied to the electrode film adhesive roller 150 when the first bonding operation is performed while the electrode film 20 and the first sub-pad 10a pass between the first sub-pad adhesive roller 160a and the electrode film adhesive roller 150, and the electrode film 20 is in contact with the electrode window 13a of the first sub-pad 10a. Furthermore, in order to discontinuously supply the electrode film 20 and reduce the amount of electrolyte membrane 21 used therein, the electrode film adhesive roller 150 can fluidly change its position within a specific range.

[0056] Therefore, by discontinuously supplying electrode film sheets 20 with gaps 24, thereby reducing the amount of electrolyte membrane 21 used while continuously supplying the first sub-pad sheet 10a and the second sub-pad sheet 10b, a membrane electrode assembly (MEA) can be manufactured in which the minimum length of the electrolyte membrane 21 protrudes between the sub-pad sheets, and the electrolyte membrane 21 is bonded to the sub-pad sheets together with the electrode catalyst layer 22.

[0057] Figure 3D This is a detailed cross-sectional view of the electrode film sheet 20 supplied to the electrode film sheet bonding roller 150. (Refer to...) Figure 3D In part D, the electrode film sheet 20 includes a gap 24 formed within it. The gap 24 can be a space between one end of an electrolyte membrane 21 and a corresponding end of an adjacent electrolyte membrane 21, one end of which is included in the electrode film sheet 20 and formed by a punching process. The gap 24 can be approximately 2-34 mm.

[0058] When the gap 24 is less than about 2 mm, the punching area cannot be guaranteed in the punching process, and when the gap 24 exceeds about 34 mm, the amount of electrolyte membrane 21 consumed is greater than the required amount, and the amount of electrolyte membrane saved is reduced. The first sub-gasket sheet bonding roller 160a can be arranged on one side of the first sub-gasket cutter 120a along the flow direction of the process. In particular, the first sub-gasket sheet bonding roller 160a and the electrode film sheet bonding roller 150 can be arranged to contact each other.

[0059] Figures 5A to 5D This is an enlarged structural diagram showing the first bonding process, in which an electrode film sheet supplied from an electrode film sheet bonding roller and a first sub-pad sheet continuously supplied from a first sub-pad sheet bonding roller are bonded together. First, refer to... Figure 5A When the electrode film sheet 20 contacts the first sub-pad 11a included in the first sub-pad sheet 10a, the operation of the electrode film sheet adhesive roller 150 configured to supply the electrode film sheet 20 can be stopped.

[0060] Reference Figure 5BWhen the electrode film sheet 20 contacts the electrode window 13a included in the first sub-pad sheet 10a continuously supplied from the first sub-pad sheet bonding roller 160a, the electrode film sheet bonding roller 150 can begin operating together with the continuously operating first sub-pad sheet bonding roller 160a, thereby initiating a first bonding operation to bond the electrode film sheet 20 to the first sub-pad sheet 10a. In other words, the electrode film sheet bonding roller 150 can only operate discontinuously when the electrode film sheet 20 contacts the electrode window 13a.

[0061] The electrode film bonding roller 150 and the first sub-pad film bonding roller 160a can be heated rollers. Therefore, referring to... Figure 5C A first bonding operation can be performed, wherein the electrode film sheet 20 and the first sub-pad sheet 10a are hot-pressed together by means of an electrode film sheet bonding roller 150 and a first sub-pad sheet bonding roller 160a. Specifically, the hot-pressing temperature can be approximately 10–200°C, particularly approximately 100°C or lower. When the hot-pressing temperature exceeds approximately 100°C, the processability decreases due to the thermoplasticity of the electrolyte membrane 21, and when the hot-pressing temperature exceeds approximately 200°C, the performance of the electrolyte membrane 21 deteriorates.

[0062] Subsequently, the first bonding operation can be performed until the contact area between the electrode film sheet 20 and the electrode window 13a of the first sub-pad sheet 10a terminates. (Refer to...) Figure 5D When the contact area between the electrode film sheet 20 and the electrode window 13a of the first sub-pad sheet 10a terminates, the electrode film sheet 20 may contact the first sub-pad 11a included in the first sub-pad sheet 10a, thereby allowing the electrode film sheet bonding roller 150 to return to its original position and its operation to cease. Specifically, the protective film 23 included in the electrode film sheet 20 can be removed from the electrode film sheet 20. Furthermore, the first sub-pad sheet bonding roller 160a can be configured to continuously supply the first component 30 manufactured after the first bonding operation to the second sub-pad sheet bonding roller 160b. Figure 3E This is a sectional view of the first component 30 in part E.

[0063] Figure 6This is an enlarged structural view showing the bonding position between the electrode film adhesive roller and the first sub-pad film adhesive roller according to an exemplary embodiment of the present invention. Referring to this figure, the electrode film adhesive roller 150 can be operated such that when a first bonding operation is performed through contact between the electrode film 20 and the electrode window 13a included in the first sub-pad film 10a, the electrode film adhesive roller 150 can be configured to perform rotational motion at the contact point 151 where the electrode film 20 contacts the first sub-pad film adhesive roller 160a, and then perform linear motion at the point where the electrode film 20 does not contact the first sub-pad film adhesive roller 160a.

[0064] The electrode film adhesive roller 150 and the first sub-pad adhesive roller 160a can be arranged such that the angle θ formed by the straight line 153, including the contact point 151 (where the electrode film adhesive roller 150 rotates), and the straight line 152 on the linear motion path is 0–90°. Specifically, this minimizes the pressure variation of the second adhesive operation performed simultaneously with the first adhesive operation between the first sub-pad adhesive roller 160a and the second sub-pad adhesive roller 160b. When the electrode film adhesive roller 150 contacts the first sub-pad adhesive roller 160a, the simultaneous operation can be performed by applying a physical impact to the first sub-pad adhesive roller 160a due to the tolerance of the linear motion. The angle θ between the straight line 153, including the contact point 151 where the electrode film adhesive roller 150 rotates, and the straight line 152, including the point where the electrode film adhesive roller 150 rotates, can be 0°.

[0065] Furthermore, the weight of the electrode film bonding roller 150 can be less than or greater than the weight of the first sub-pad film bonding roller 160a. Specifically, in order to minimize the pressure variation of the second bonding operation performed simultaneously with the first bonding operation between the first sub-pad film bonding roller 160a and the second sub-pad film bonding roller 160b by applying a physical impact to the first sub-pad film bonding roller 160a due to the tolerance of the linear motion when the electrode film bonding roller 150 contacts the first sub-pad film bonding roller 160a, the weight of the electrode film bonding roller 150 can be less than the weight of the first sub-pad film bonding roller 160a. The second sub-pad film bonding roller 160b can be arranged on the first sub-pad film bonding roller 160a, specifically, the second sub-pad film bonding roller 160b can be arranged on the first sub-pad film bonding roller 160a so that they are in contact with each other.

[0066] After the first bonding operation, a first component continuously supplied from a first sub-gasket sheet bonding roller 160a and a second sub-gasket sheet 10b continuously supplied from a second sub-gasket sheet bonding roller 160b can pass between the first sub-gasket sheet bonding roller 160a and the second sub-gasket sheet bonding roller 160b, and thus can be bonded a second time, thereby enabling the preparation of a second component. The first sub-gasket sheet bonding roller 160a and the second sub-gasket sheet bonding roller 160b can be hot rollers. Therefore, a second bonding operation can be performed, wherein hot-press bonding between the first sub-gasket sheet 10a and the second sub-gasket sheet 10b is performed by the first sub-gasket sheet bonding roller 160a and the second sub-gasket sheet bonding roller 160b.

[0067] Specifically, the hot-pressing bonding temperature can be about 10–200°C, particularly 100°C or lower. When the hot-pressing bonding temperature exceeds about 100°C, the processability of the electrolyte membrane 21 decreases due to its thermoplasticity, and when the hot-pressing bonding temperature exceeds about 200°C, the performance of the electrolyte membrane 21 deteriorates. Thereafter, the second bonding operation can use bonding methods commonly used in the art to which this invention pertains, particularly full-surface bonding methods. Figure 3F It is a sectional view of the second component included in part F.

[0068] Reference Figure 2 The anti-step reinforcing adhesive roller 170 can be arranged on one side of each of the first sub-pad sheet adhesive roller 160a and the second sub-pad sheet adhesive roller 160b in the flow direction of the process after the second adhesive operation. The second assembly, continuously supplied from the first sub-pad sheet adhesive roller 160a and the second sub-pad sheet adhesive roller 160b after the second adhesive operation, can be third-bonded between the anti-step reinforcing adhesive roller 170, thereby enabling the fabrication of a membrane electrode assembly (MEA). Such a third adhesive operation can utilize adhesive methods commonly used in the art to which this invention pertains, particularly reinforcing adhesive methods.

[0069] Figure 7C This is a cross-sectional view showing the anti-step reinforcement adhesive roller. Figure 7D This is a front view of the membrane electrode assembly (MEA) after the enhanced bonding operation. Referring to these figures, due to the material differences at various locations caused by the reduction in the amount of electrolyte membrane 21 used, step portions may form in the second assembly. Therefore, to prevent the formation of step portions in the second assembly, an anti-step enhanced bonding roller 170 may be arranged in the outer region in the lateral direction relative to the advancing direction of the second assembly during the third bonding operation.

[0070] Figure 8A and Figure 8BThis is a schematic diagram illustrating the structure of a buffer roller additionally included in a manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention. Referring to these figures, the manufacturing apparatus 100 used in the method for manufacturing a membrane electrode assembly (MEA) may further include a buffer roller 180, and the buffer roller 180 may perform a movement that compensates for path deviations in linear motion.

[0071] A buffer roller 180 can be arranged between the electrode film cutter 140 and the electrode film sheet bonding roller 150. The electrode film sheet bonding roller 150 can be configured to perform linear motion at a point where the electrode film sheet 20 does not contact the first sub-pad sheet bonding roller 160a. In particular, the electrode film sheet bonding roller 150 can fluidly change its position within a certain range, and the electrode film sheet 20 can be configured to perform linear motion between the position-changing electrode film sheet bonding roller 150 and the electrode film cutter 140.

[0072] In other words, path deviation may occur during the linear movement of the electrode film 20 between the electrode film bonding roller 150 and the electrode film cutter 140. When this process is performed with the buffer roller 180 positioned between the electrode film bonding roller 150 and the electrode film cutter 140, such as... Figure 8A and Figure 8B As shown, the buffer roller 180 can be configured to perform a motion that counteracts path deviations in linear motion. Therefore, the possibility of stretching deformation of the electrolyte membrane 21 and defective products due to path differences can be reduced.

[0073] The manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention can be any manufacturing apparatus capable of performing the method, but is not limited thereto. For example, such as Figure 2 As shown, the manufacturing apparatus can have an electrode film sheet bonding roller 150, a first sub-pad sheet bonding roller 160a, and a second sub-pad sheet bonding roller 160b connected adjacent to each other, or configured such that a first sub-pad sheet 10a supplied from the first sub-pad sheet bonding roller 160a is transferred to a vacuum conveyor belt and first bonded to an electrode film sheet 20 supplied from the electrode film sheet bonding roller 150 to prepare a first assembly. The first assembly can be conveyed and thermally compressed in the forward direction of the heated vacuum conveyor belt, and then secondly bonded to a second sub-pad sheet 10b supplied from the second sub-pad sheet bonding roller 160b to prepare a second assembly. Subsequent operations can then be the same as or different from the method described above.

[0074] The invention will be described in more detail below through the following embodiments. However, these examples are merely illustrative and are not intended to limit the scope of the invention.

[0075] Example - Manufacturing MEA by the method according to the invention

[0076] like Figure 8A and Figure 8B As shown, in addition to the manufacturing apparatus used in a method for manufacturing a membrane electrode assembly (MEA) according to an exemplary embodiment of the present invention, the manufacturing apparatus may further include a buffer roller 180.

[0077] The materials and specifications used are as follows. Commercially available film materials such as PI, PET, and PEN, along with an epoxy resin-based adhesive, are used to prepare the first sub-shield sheet 10a and the second sub-shield sheet 10b. The electrode catalyst layer 22 and the electrolyte membrane 21 are prepared according to the specifications of the NEXO manufactured by Hyundai Motor Company. Furthermore, the depth of the perforated plate 141a included in the perforating roller 141 is 20 μm. Additionally, the gap in the electrode membrane sheet 20 prepared by the perforating roller 141 is 20 mm.

[0078] Furthermore, the hot-press bonding temperature between the electrode film sheet 20 and the first sub-pad sheet 10a via the electrode film sheet bonding roller 150 and the first sub-pad sheet bonding roller 160a is 60-110°C, and the hot-press bonding temperature between the first sub-pad sheet 10a and the second sub-pad sheet 10b via the first sub-pad sheet bonding roller 160a and the second sub-pad sheet bonding roller 160b is also 60-110°C. Accordingly, a membrane electrode assembly (MEA) with reduced electrolyte membrane 21 usage is manufactured.

[0079] Comparative Example – Manufacturing of MEA

[0080] A first sub-shield sheet 10a and a second sub-shield sheet 10b are prepared using commercially available film materials such as PI, PET, and PEN, and an epoxy resin-based adhesive. An electrode catalyst layer 22 and an electrolyte membrane 21 are prepared according to the specifications of a Hyundai NEXO manufactured by Hyundai Motor Company. For comparison, the electrolyte membrane 21 is applied to the entire sub-shield sheet except for the portion surrounding the electrode.

[0081] Test Example – Airtightness and Performance Verification of MEA

[0082] The membrane electrode assemblies (MEAs) fabricated in the example and comparative examples were evaluated using the following methods, and the evaluation results are shown in Table 1 and... Figure 10 and Figure 11 .

[0083] Evaluation methods

[0084] 1.1. Air tightness verification: After applying pressure based on standards set by the inventors, the pressure reduction is measured within a specific time period.

[0085] 2.2 Performance verification: Under conditions of applying a fixed amount of air / hydrogen based on standards set by the inventors, the voltage is measured at a specific current density.

[0086] Table 1

[0087]

[0088] Referring to Table 1, as a result of the airtightness verification, the MEA manufactured in the example of the present invention has an airtightness level equal to that of the MEA manufactured in the comparative example.

[0089] Furthermore, as a performance verification result, it can be determined that, under variable pressure conditions and atmospheric pressure conditions, the MEA manufactured in the example of this invention has equivalent performance (durability) to the MEA manufactured in the comparative example, as shown in Table 1. Figure 10 and Figure 11 As shown. Furthermore, it can be confirmed that the MEA manufactured in the examples of the present invention has the same performance (durability) as the MEA manufactured in the comparative examples under both low-temperature and high-temperature conditions, and the MEA manufactured in the examples of the present invention does not cause adhesive surface abnormalities under room temperature conditions.

[0090] Therefore, in the membrane electrode assembly (MEA) manufactured according to the present invention, the electrolyte membrane of minimum length protrudes between the sub-pad sheets, and the electrolyte membrane is bonded to the sub-pad sheets together with the electrode catalyst layer. Thus, the membrane electrode assembly (MEA) can minimize the electrolyte membrane present in the non-power generation area and have performance equivalent to that of a conventional membrane electrode assembly (MEA).

[0091] As is evident from the above description, in the manufacturing method of a membrane electrode assembly (MEA) that combines a roll-to-roll method and a stop-and-go method, the first and second sub-pad sheets can be supplied continuously, while electrode membrane sheets with gaps can be supplied discontinuously, thus reducing the amount of electrolyte membrane used. Therefore, the minimum length of the electrolyte membrane protrudes between the sub-pad sheets, and the electrolyte membrane, together with the electrode catalyst layer, can be bonded to the sub-pad sheets. Thus, the amount of electrolyte membrane used in non-power generation areas can be reduced by approximately 50%. Furthermore, the electrolyte membrane can be prevented from being exposed at the edges of the MEA, thereby preventing generated water from leaking to the outside of the MEA.

[0092] The invention has been described in detail with reference to exemplary embodiments thereof. However, those skilled in the art will recognize that changes can be made to these exemplary embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for manufacturing a membrane electrode assembly, comprising: Unwind the first and second sub-gasket sheets that are wound into rolls and supply the first and second sub-gasket sheets; Electrode windows are continuously formed in the supplied first and second sub-gasket sheets using a first sub-gasket cutter and a second sub-gasket cutter, such that the electrode windows are spaced apart from each other by a predetermined interval; The first sub-pad sheet and the second sub-pad sheet, which are provided with continuously formed electrode windows, are continuously supplied to the first sub-pad sheet bonding roller and the second sub-pad sheet bonding roller. The electrode film sheet, which is wound into a roll on the electrode film sheet unwinder, is unwound and supplied; A gap is continuously formed in the supplied electrode film using an electrode film cutter, such that the gaps are spaced apart from each other by a predetermined interval; Electrode film sheets with gaps are supplied to electrode film sheet bonding rollers; The first bonding is achieved by passing the first sub-pad sheet and the electrode film sheet between the first sub-pad sheet bonding roller and the electrode film sheet bonding roller, thereby bonding the supplied first sub-pad sheet and the supplied electrode film sheet to form a first assembly; The second bonding involves bonding a first component supplied from a first sub-gasket sheet bonding roller to a second sub-gasket sheet supplied from a second sub-gasket sheet bonding roller, following the first bonding, to form a second component. This second bonding is performed by passing the first component and the second sub-gasket sheet between the first and second sub-gasket sheet bonding rollers. The electrode film unwinder is configured to unwind and discontinuously supply the electrode film. The electrode film bonding roller is operated such that when a first bonding operation is performed through contact between the electrode film and the electrode window included in the first sub-pad film, the electrode film bonding roller rotates at the contact point where the electrode film and the first sub-pad film bonding roller are in contact, and then moves linearly at the point where the electrode film and the first sub-pad film bonding roller are not in contact. Specifically, when the electrode film sheet is supplied to the electrode film sheet bonding roller, and the first bonding is performed while the electrode film sheet is in contact with the electrode window of the first sub-pad sheet, the electrode film sheet is supplied to the electrode film sheet bonding roller discontinuously.

2. The method for manufacturing a membrane electrode assembly according to claim 1, further comprising: The third bonding is performed by bonding the second component supplied from the first sub-pad sheet bonding roller and the second sub-pad sheet bonding roller after the second bonding, the third bonding being carried out by passing the second component between the anti-step reinforcement bonding rollers.

3. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, The electrode film includes: Electrolyte membrane; An electrode catalyst layer is formed on the central portion of the first and second surfaces of the electrolyte membrane; and A protective film is disposed on the outer surface of one of the electrode catalyst layers.

4. The method for manufacturing a membrane electrode assembly according to claim 3, wherein, The protective film is removed after the first bonding.

5. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, Continuous gap formation includes: A punching process is used to separate portions of the electrolyte membrane of the electrode membrane sheet to form gaps. Remove the separated portion of the electrolyte membrane; Collect the portion of electrolyte membrane that has been removed.

6. The method for manufacturing a membrane electrode assembly according to claim 5, wherein, The depth of the perforated plate included in the perforating roller is 15-250 μm.

7. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, The size of the gap is 2-34mm.

8. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, Before the first bonding, gaps are formed in the electrode film sheet, and the electrode film sheet with gaps is supplied to the electrode film sheet bonding roller via a pair of buffer rollers.

9. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, The electrode film film bonding roller and the first sub-pad film bonding roller are arranged in such a position that the angle formed by the straight line including the contact point that is rotating and the straight line on the path of the straight line is less than 90 degrees.

10. The method for manufacturing a membrane electrode assembly according to claim 1, wherein, The weight of the electrode film bonding roller is less than the weight of the first sub-pad film bonding roller.

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