JP2010146796A - Manufacturing method and manufacturing device of membrane-electrode assembly for fuel cell - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To coat catalyst ink and resin ink on a web-like electrolyte film conveyed on a roll-to-roll manufacturing line upon manufacturing a membrane electrode assembly for a fuel cell to form a catalyst layer and a ladder-like sealing portion surrounding the catalyst layer on the web-like electrolyte film. <P>SOLUTION: In order to form both side parts 6R, 6L of the ladder-like sealing portion 6, the resin ink is coated on the web-like electrolyte film 7 during conveyance, with the use of slit dies 22 each with an inverse concave ink discharge part on either side. At the same time, in order to form the catalyst layer 5 and the sealing portion at an intermediate region where the electrolyte film 7 pinched by the both side parts 6R, 6L is exposed, the slit die 55 with an opening in a direction vertical to a conveying direction and the slit die 44 are changed over at a constant period to alternately coat the catalyst ink 5 and the resin ink 6 on the electrolyte film 7. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a membrane-electrode assembly (MEMBRANE-ELECTRODE ASSEMBLY: abbreviated as “MEA”) and a manufacturing apparatus therefor, and more particularly, to roll-to-roll (ROLL) when manufacturing MEA. It can be applied to TO ROLL production lines, and the catalyst layer applied and formed on the web-like (or long tape-like) electrolyte membrane being transported and the frame-like seal part (gasket part) surrounding this catalyst layer The present invention relates to the same manufacturing method and apparatus for forming the same by applying catalyst ink and resin ink.

For example, Patent Document 1 proposes an MEA manufacturing method and manufacturing apparatus using a roll-to-roll manufacturing line, and the following is presented. First, the web-shaped electrolyte membrane and the perforation (perforation for excision; the same applies hereinafter) are unrolled into a ladder-like shape (see FIG. 9 of Patent Document 1) and both are brought into contact with each other. Join. Thereafter, the member is cut from the perforation of the web-shaped edge seal member to form a plurality of rectangular openings, and the catalyst layer is formed on the surface of the electrolyte membrane exposed from the openings (hereinafter referred to as “active area” as appropriate). The MEA is continuously manufactured (mass-produced) by incorporating the process for forming the gasket seal portion, which has been performed for each sheet, into the mass-production line of roll-to-roll, so as to be applied and formed with catalyst ink.
JP 2007-299551 A

However, the manufacturing technique of Patent Document 1 has the following problems.
First, in the manufacturing technique, an active area is cut out so that a web-like gasket sealing portion (hereinafter, abbreviated as “sealing portion” as appropriate) can be easily conveyed by a roll. In order to facilitate this excision, the seal portion is half cut (see paragraph [0039] and paragraph [0040] of Patent Document 1). When the seal portion is wound into a roll by this half cut, the roll The strength (tensile strength, bending strength, etc.) of the shaped web is reduced. When unwinding and transporting the seal part from the roll, it is necessary to apply tension to the roll-shaped web serving as the sheet part. At this time, the roll-shaped web is broken, wrinkled or stretched due to the half-cut portion. There is a risk. In order to prevent such a phenomenon, measures such as reducing the half-cut amount and / or reducing the tension on the rolled web during conveyance can be considered. However, according to the former, the active area can be cut cleanly. According to the latter, slip may occur between the roll contact portion of the web (sheet member) being conveyed. In consideration of these possibilities, it is extremely difficult to determine the half-cut amount that does not cause the above problem and to perform tension control during conveyance.

  Furthermore, according to the manufacturing technique shown in Patent Document 1, when cutting an active area, it is necessary to restrain an object that is not cut [in this paragraph, a product (referred to as MEA or a component thereof)]. As shown in FIG. 4 of Patent Document 1, not only a catalyst layer forming portion (corresponding to an active area) but also a manifold opening is present in the seal portion, which has a very complicated frame structure. . Therefore, when restraining the product, it is necessary to press and fix other than these removed portions, but there are very few places to be used as a pressing area (pressing portion). In order to obtain a sufficient restraining force, it is necessary to suppress a large area with a large force. However, if the area becomes small, it is necessary to suppress the region with a larger force, which causes damage to the product. In particular, since miniaturization is required for automobiles, portable electrical devices, and the like that use recent fuel cells, in actual products, the pressing portion must be designed to be as small as possible. From this point of view, it is extremely difficult to excise the active area without damaging the product.

  In view of such circumstances, the present invention applies the catalyst layer catalyst ink and the seal portion resin ink to the web-like electrolyte membrane being conveyed without providing a step of cutting the active area from the seal portion, An object of the present invention is to provide a fuel cell MEA manufacturing method and a manufacturing apparatus for forming a ladder-shaped seal portion surrounding the catalyst layer on a web-like electrolyte membrane being conveyed by a coating apparatus and its control.

(Aspect of the Invention)
Hereinafter, embodiments of the invention will be shown and described. The items (1) to (6) correspond to the claims 1 to 6.

(1) A ladder-like seal portion provided with a web-like electrolyte membrane with long side portions and a ladder-like step portion perpendicular to the both side portions at a constant interval, and a frame shape within the ladder-like seal portion And a catalyst layer surrounded by a method for producing a membrane-electrode assembly, wherein the side portion formed on the ladder-shaped seal portion being linearly conveyed is provided with resin ink for a seal portion. In order to form the catalyst layer on the first step of forming the both side portions of the ladder-like seal portion by continuously applying and the exposed portions of the electrolyte sandwiched between the both sides of the ladder-like seal portion And a second step of applying the sealing portion resin ink for forming the ladder-like step portion periodically and alternately in a certain width along the transport direction. Fuel cell featuring For producing a membrane-electrode assembly for use in an automobile.

According to this section, a ladder-like seal portion and a catalyst layer surrounded by a frame shape on the ladder-like seal portion can be formed only by coating on the web-like electrolyte membrane. Complicated processes such as tension control of the electrolyte membrane and the seal part for the web-like gasket, removal of the active area forming the catalyst layer, and accurate alignment of the electrolyte membrane and catalyst layer exposed from the removed active area Can be omitted. Therefore, production efficiency and yield of the membrane-electrode assembly (MEA) can be improved.
According to this section, a continuous body of MEAs is manufactured in a web shape, but a sheet-fed MEA is manufactured by cutting the substantially central portion of the ladder-like step portion of the ladder-like seal portion in a direction perpendicular to the conveying direction. can do.

  The “ladder-like seal portion” is a continuous body of the frame-like seal portion, and “ladder-like” refers to a perforation-like state formed on the upper side or the lower side of the silver salt film. The “ladder-like seal” is a protective film that protects the gasket and electrolyte from protrusions (carbon fiber, fluff, etc.) of the gas diffusion layer (GAS DIFFUSION LAYER: “GDL”) in a fuel cell (single cell). Function as.

(2) The method for producing a membrane-electrode assembly for a fuel cell according to (1), wherein the first step and the second step are performed simultaneously.
This section exemplifies parallel processing of the operations in the first step and the second step of (1). That is, while applying the resin ink to both long side portions of the web-like electrolyte membrane, the resin ink is applied to the ladder-like step portions perpendicular to the electrolyte membrane sandwiched between both sides simultaneously or in parallel. This is an MEA manufacturing method in which a catalyst ink is applied between adjacent ladder-like step portions.
According to this section, it is possible to form a ladder-like seal portion that surrounds the catalyst layer and the catalyst layer in the shape of a frame simultaneously with the conveyance of the web-like electrolyte membrane, so that the manufacturing time can be greatly shortened.

  First, a ladder-like seal portion is provided on the electrolyte membrane, which is provided with a long side portion and a ladder-like step portion that is perpendicular to the both side portions and at regular intervals. A MEA can also be produced by forming a catalyst layer between the step portions. In this case, after completion of the first step, in the second step, first, supply of the catalyst ink from the catalyst ink is stopped so that the catalyst ink is not applied, and the catalyst ink nozzle is idled. As a result, a ladder-like seal portion is formed on the electrolyte membrane (the above steps are referred to as “second step A”). Then, this time, the supply of the resin ink for the seal part is stopped so that the resin ink for the seal part is not applied, and the nozzle for the resin ink for the seal part is idled, while the catalyst layer ink is removed from both sides and the step. It is made to apply | coat to the electrolyte membrane which is surrounded and exposed (this step is called the 2nd process B). That is, after the first step is finished, the second step A and then the second step B may be provided in order.

(3) a ladder-like seal portion provided with a ladder-like step portion perpendicular to the both side portions of the web-like electrolyte membrane and at a regular interval with respect to the two side portions; and a frame-like shape in the ladder-like seal portion An apparatus for manufacturing a membrane-electrode assembly for forming an enclosed catalyst layer, comprising: an ink application device for applying a catalyst ink and a resin ink for forming a ladder seal portion to the web-like electrolyte membrane; The coating device applies and forms the ladder seal portion forming resin ink and the catalyst ink on the web-like electrolyte film conveyed linearly so that the ladder layer surrounds the catalyst layer in a frame shape. An apparatus for producing a membrane-electrode assembly for a fuel cell, comprising control means for controlling the fuel cell so as to do so.

  This section shows the manufacturing apparatus that can carry out the manufacturing method of the membrane-electrode assembly for a fuel cell according to the section (1). Therefore, since the same effect as the item (1) is produced, the description is omitted. In addition, this term does not limit the production method of item (1), and the production apparatus for carrying out the production method of item (1) can be appropriately changed by those skilled in the art.

(4) The ink application apparatus includes first, second, and third ink ejection units whose ejection operations are controlled by the control unit, and the first, second, and third ink ejection units include: The resin ink is arranged on substantially the same plane on the electrolyte membrane, and the resin ink is directed to the electrolyte membrane corresponding to the both sides of the ladder frame of the seal portion to the first ink discharge means. And a command for discharging the catalyst ink and the resin ink toward the electrolyte alternately to the second ink ejecting means and the third ink ejecting means at regular intervals. Output to the first, second and third ink ejection means. 4. The manufacturing apparatus according to claim 3, wherein

This section exemplifies the configuration and operation of the ink coating apparatus of section (3). Resin ink is applied to the electrolyte membrane by the first ink discharge means so as to form both sides of the frame portion of the ladder-like seal portion (in parallel with railroad rails).
On the other hand, on the electrolyte membrane sandwiched between both sides, the step portions of the catalyst layer and the ladder-shaped seal portion are alternately formed at regular intervals by the second ink discharge means and the third ink discharge means. . Each ink ejection unit is driven (ink ejection) by a command from the control unit, but the necessary control conditions such as the above-described fixed period and the timing at which the second ink ejection unit and the third ink ejection unit are alternately switched are set. Pre-stored in the control means.
“The first, second, and third ink ejection means are arranged on the electrolyte membrane in substantially the same plane” means that the ink ejection openings (slits) of the first, second, and third ink ejection means. In the case of a die, it means that the tip of a slit) is substantially in the same plane at least during ink ejection (application).

(5) The first, second, and third ink discharge means include a slit die, and the slit die includes a slit-like discharge port that discharges each ink to the electrolyte membrane, and the slit die of the slit die The manufacturing apparatus according to (4), wherein the longitudinal direction is set to be perpendicular to the transport direction.

  This section exemplifies the first, second and third ink discharge means described in the section (4). In general, the surface shape of the MEA of a polymer electrolyte fuel cell (including a direct methanol fuel cell) is rectangular, and therefore the catalyst layer formed therein is also rectangular, and this catalyst layer is framed. Since each of the ladder-shaped sealing portions surrounding the shape is a rectangle having a frame-shaped opening, it is preferable to use a known slit die for each ink discharge means, and an extremely thin rectangular slit that is an ink discharge port of the slit die is used. By setting each ink in the direction perpendicular to the transport direction and applying and forming each ink on the electrolyte membrane according to the command of the control means, the rectangular catalyst layer and the ladder shape surrounding it in a frame shape quickly and smoothly The seal portion can be formed.

(6) The first ink ejecting means includes two slit dies capable of ejecting the resin ink perpendicularly to the electrolyte membrane from the slit dies, and a fixed length for connecting the two slit dies apart. The vertical cross section has a structure of a reverse concave portion, and the fixed length of the support member is equal to or longer than the length of the catalyst layer in the direction perpendicular to the transport direction, and The manufacturing apparatus according to (5), wherein a height of the support member is set at a position higher than a top surface of the catalyst layer.

  This section exemplifies the configuration (structure) of the first ink discharge means. The first ink discharge means applies both sides of the ladder frame of the seal portion (parallel long portions along the transport direction) simultaneously using the same resin ink for the seal portion. It includes two slit dies that are spaced apart. These two slit dies are perpendicular to the surface of the electrolyte membrane so that ink is ejected substantially perpendicular to the surface of the electrolyte membrane, and so that the slit of the slit die is perpendicular to the transport direction. Is set. During ink ejection (ink application), the two slit dies should be straddled across the surfaces sandwiched between both sides (the catalyst layer and the continuous surface of the step portion of the ladder frame) with two legs. The vertical section of the first ink discharge means has a reverse concave structure. For this reason, while the first ink discharge means is driven, the continuous surface of the seal portion of the step portion of the ladder layer frame is not damaged.

  According to the present invention, the catalyst layer catalyst ink and the seal portion resin ink are applied to the web-like electrolyte membrane being conveyed without providing a step of cutting the active area from the seal portion, and the catalyst layer and the catalyst A ladder-like seal portion surrounding the layer in a frame shape can be formed on the web-like electrolyte membrane being conveyed by a coating apparatus and its control.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. FIGS. 1A and 1B are examples of embodiments for carrying out the invention (hereinafter referred to as “this embodiment”). In the drawings, the same reference numerals denote the same components.

  FIGS. 1A and 1B are conceptual diagrams of an apparatus for manufacturing an MEA that can be applied to a roll-to-roll mass production line according to the present embodiment [(a) is a schematic top view, and (b) is a schematic cross section. Figure]. As shown in FIGS. 1A and 1B, the apparatus is unwound from an unwinding roll (not shown; corresponding to reference numeral 20 </ b> A in FIG. 5), and is transported in the transport direction indicated by arrow 9. A catalyst layer is applied to the electrolyte membrane 7 supported on the carrier film 8 by using a coating apparatus 10 on the electrolyte membrane 7 exposed in a ladder-like seal portion 6 and a ladder space of the seal portion 6 (corresponding to reference numeral 5). 5, and MEA is continuously manufactured (mass production).

  Furthermore, this embodiment will be described with reference to FIG. The coating device 10 includes four ink discharge nozzles 1, 2, 3, and 4 (hereinafter, referred to as “nozzles 1, 2, 3, and 4” as appropriate). The nozzles 1, 2, and 3 are arranged adjacent to each other in this order in the direction perpendicular to the transport direction of the electrolyte membrane 7 indicated by the arrow 9, and the nozzle 4 is adjacent to the nozzle 2 in a direction parallel to the transport direction. Are arranged. Since the electrolyte membrane 5 is usually rectangular and the ladder-shaped seal portion 6 is also a shape combining a plurality of rectangles, the ink ejection of each nozzle 1, 2, 3 and 4 corresponds to the shape of the ink application target. The cross-sectional shape of the part is preferably rectangular. However, the nozzles 1, 2, 3, and 4 may have a very thin rectangle, or only the tip may have a very thin rectangle (linear shape). A known slit die is preferable as the ink discharge means satisfying such conditions.

  The nozzles 1, 2, 3 and 4 are connected to separate ink tanks (not shown). Resin ink for forming the seal portion 6 is accommodated in the ink tanks for the nozzles 1, 3 and 4, and catalyst ink is accommodated in the ink tank for the nozzle 2. The resin ink is preferably, for example, a moisture-curing adhesive such as silicone, urethane, or acrylic, or a gasket, and the catalyst ink is, for example, a catalyst-supported catalyst such as platinum-supported carbon particles or Nafion (registered trademark). What disperse | distributed electroconductive particle and electrolyte resin material in organic solvents, such as water and ethanol, methanol, is preferable. It is preferable that the resin ink and the catalyst ink have such a viscosity that the resin ink and the catalyst ink come into contact with each other at the boundary between the seal portion 6 and the catalyst layer 5 and are slightly dissolved after drying. By doing so, it is possible to prevent the electrolyte membrane 7 from being exposed at the boundary between the seal portion 6 and the catalyst layer 5, and to the electrolyte membrane 7 of the protrusions (carbon fiber, fluff, etc.) from the gasket and GDL of the seal portion 6. As a protective film for preventing rustling, the sealing function and the strength enhancing function can be improved, and the performance and durability of the fuel cell can be improved.

  The coating apparatus 10 including the nozzles 1, 2, 3, and 4 is fixedly disposed at a fixed position above the surface on which the electrolyte membrane 7 is conveyed, and the ink discharge ports of the nozzles 1, 2, 3, and 4 are arbitrarily selected. It is preferable to drive the ink in such a manner that the ink discharge direction is variable in parallel with this direction, particularly in the transport direction. While the electrolyte membrane 7 is transported in the transport direction, each nozzle 1 is applied in accordance with a command (signal) from the control means described later using a coating method such as a die coater method, an ink jet method, or a screen printing method. 2, 3 and 4 are applied to the electrolyte membrane 7. The solvent content, moisture, and the like in the applied catalyst ink and resin ink are vaporized and dried by a drying means (reference numeral 50 in FIG. 2), which will be described later, and surrounds the catalyst layer 5 and the catalyst layer 5 in a ladder-like seal portion 7. Is formed on the electrolyte membrane 7 to produce a plurality of MEAs.

Next, control means for discharging catalyst ink and resin ink from the nozzles 1, 2, 3, and 4 to the electrolyte membrane 7 will be described.
First aspect: In this first aspect, the resin ink from the nozzles 1 and 3 for forming both side portions 6R and 6L is always ejected, while the nozzle 2 for forming the catalyst layer 5 is used. And the resin ink from the nozzle 4 for forming the step portion 6 are controlled to be alternately discharged while switching between the nozzle 2 and the nozzle 4 at a constant cycle. For example, the period T (T = t ₁ + t ₂ ) shown in FIG. 1A is used, where t ₁ is the time for applying the electrolyte membrane 7 between the adjacent catalyst layers 5 and 5 with resin ink, t ₂ is a time corresponding to the time for applying the catalyst layer 5 with the catalyst ink. First, at time t ₁ , the resin ink from the nozzle 4 is ejected, and at time t ₂ , the catalyst from the nozzle 2 instead. Control to eject ink. Therefore, by changing the time t ₁ and the time t ₂ , the size of the ladder portion of the ladder-like seal portion 6 in the transport direction, that is, the size of the catalyst layer 5 can be changed.

  Regarding the ejection of each ink from the nozzle 2 and the nozzle 4, it is preferable that the nozzle 2 and the nozzle 4 are immediately switched because there is no possibility that the exposed surface of the electrolyte membrane 7 is generated. However, it is desirable that the tip width of the nozzle in the direction perpendicular to the nozzle is as narrow as possible and that the distance between the two nozzles is reduced.

  As described above, according to the first aspect, the above-described nozzle structure and control thereof, unlike the manufacturing method of Patent Document 1, the process of half-cutting the seal part and the excision of the seal part for creating an active area are performed. In addition, there is no process, and in addition, since the drying process required for forming the catalyst layer 5 and the ladder-shaped seal portion 6 can be shared, the process becomes simple.

  Second Aspect: In the second aspect, the seal portion 6 is first applied and formed on the electrolyte membrane 6 among the catalyst layer 5 and the seal portion 6. More specifically, in FIG. 1 (a), while the electrolyte membrane 6 is conveyed in the direction indicated by the arrow 9, the catalyst ink from the nozzle 2 is discharged, and the resin ink is first discharged from the nozzles 1, 3 and 4 to the electrolyte membrane. 7 is discharged. At this time, the nozzles 1 and 3 always discharge the resin ink to the electrolyte membrane 7, but the nozzle 4 periodically and intermittently removes the resin ink 6 with the length in the transport direction of the electrolyte membrane 7 as the electrolyte. Discharge to the film 7. In this way, a ladder-like seal portion is first formed on the electrolyte membrane 7. Thereafter, the catalyst ink 5 is discharged from the nozzle 2 to the exposed portion (active area) of the electrolyte membrane 6. In this way, the seal portion 6 is first applied and formed on the electrolyte membrane 6, and then the catalyst ink is discharged from the nozzle 2 to the electrolyte membrane 7 that is still exposed.

  According to the second aspect, the positional relationship between the catalyst layer 5 and the seal portion 6 and the shape or size of the seal portion 6 can be easily changed regardless of the catalyst layer 5. Moreover, the selection range of the formation method of the seal | sticker part 6 also spreads. When the catalyst layer 5 is formed after the seal portion 6 is formed, the seal portion 6 in which a plurality of active areas are arranged at a constant period (a constant interval) can be used as a mask for the catalyst layer 5. The position sensor detects and grasps in advance the position, shape, and dimensions of the active area of the seal portion 6 by the position sensor that is not used, and then the catalyst ink is directed from the nozzle 2 toward the exposed surface of the electrolyte membrane 7 based on the detected data. Apply. The application by the nozzle 2 in this case is preferably an ink jet method that can easily change the application shape.

  With reference to FIG. 2, FIG. 3 and FIG. 4, an embodiment of the coating apparatus 150 used in the MEA manufacturing apparatus according to the first aspect will be described (however, the coating apparatus 150 can also be applied to the second aspect). Is). 2 (a) and 2 (b) correspond to FIGS. 1 (a) and 1 (b). Therefore, in both figures, the part which attached | subjected the same code | symbol represents the same thing.

The coating device 150 includes a slit die (nozzle) 22, a slit die (nozzle) 44, and a slit die (nozzle) 55 as ink discharge nozzles.
The slit die 22 has a three-dimensional structure in which the vertical cross section shown in FIG. 3 has a reverse concave shape, and includes a pair of slit dies 11 and 33, and a support member 22H is integrated therebetween. The support member 22H has a space S having a certain height between the slit dies 11 and 33 and the support member 22H so as not to damage the catalyst layer 5 during application (during transport of the electrolyte membrane 7). It is made shorter than the height of the slit dies 11 and 33 so as to be formed.
The slit die 22 as described above receives a command (signal) from the control means, and from both slit portions 11S and 33S (see FIG. 3) of the slit dies 11 and 33, both sides 6R portions of the electrolyte membrane 7 having a constant width at the same time. In addition, the resin ink is ejected perpendicularly to the 6L portions, and the seal portions are formed on both sides 6R and 6L portions.

  The slit die 44 is made of resin ink periodically (at regular intervals) with respect to the electrolyte membrane 7 in a direction perpendicular to the transport direction so that a bridge is formed between the 6R portion and 6L portion on both sides. ) Apply and form. The lit die 55 is obtained by applying platinum-supported carbon carbon powder, Nafion (registered trademark), etc. to ethanol on the exposed surface (active area) of the electrolyte membrane 7 other than the ladder frame portion 6 applied and formed by the slit die 22 and the slit die 44. A plurality of catalyst layers 5 are applied and formed by ejecting the catalyst ink dispersed in the catalyst.

  The slit dies 44 and 55 are driven to rotate around a rotation axis perpendicular to the transport direction according to a command from the control means (see the one-dot chain line shown in FIG. 2B). During the ink application, the ink discharge nozzles of the slit dies 44 and 55 are fixed along the direction perpendicular to the electrolyte membrane. Each of the slit dies 22, 44, and 55 is connected to an ink tank (not shown) in which resin ink, the resin ink, and catalyst ink are accommodated via a pipe member (not shown) including a drive valve (not shown). When each slit die 22, 44, 55 receives a drive command (drive signal) from the control means, the drive valve is opened, and each ink is supplied from each ink tank to each slit die 22, 44, 55. Then, each ink is controlled to be ejected from each slit die 22, 44, 55.

  Further, when the resin ink and the catalyst ink are applied to the electrolyte membrane 7 by the drive command (drive signal) output from the control means to the slit dies 22, 44, 45, the slit dies 22, 44, 45 The application operation will be described with reference to FIGS.

  First, an electrolyte membrane 7 and a carrier film 8 made of PET (polyethylene terephthalate) are overlapped and carried around an unwinding roll (see reference numeral 20A in FIG. 5), and the tip is wound up (see FIG. 5). The electrolyte membrane 7 supported on the carrier film 8 is transported in the transport direction indicated by the arrow 9.

  In this transport state (the transport speed is set to U [m / s]), the control means outputs a command (signal) that always keeps the drive state ON to the nozzle 22 (at the bottom in FIG. 4). Time chart). On the other hand, the control means outputs a command (signal) to the nozzles 55 and 44 so that the ON and OFF states of the drive state are opposite to each other for the nozzles 44 and 55 (the upper two in FIG. 4). Time chart). At this time, a time lag T occurs when the nozzle 55 and the nozzle 44 are switched. For example, the catalyst layer 5 is applied / formed by the length of the catalyst layer 5 in the transport direction by discharging the catalyst ink from the nozzle 55. At that time, the drive of the nozzle 55 is stopped and the drive of the nozzle 44 is started by a command from the control means. Next, the seal portion 6 in the transport direction is applied and formed on the portion between the catalyst layers 5 and 5 by discharging the catalyst ink from the nozzle 44. At this time, if the distance between the nozzle 55 and the nozzle 44 is L [m], the die slit slit portion of the nozzle 44 reaches the application completion position of the nozzle 55 (the die slit slit portion of the nozzle 55). Is also L [m], so the time lag until the nozzle 55 is switched to the nozzle 44 is T = L / U [s]. The time lag T [s] may be synchronized (matched) with the time when the nozzle 55 and the nozzle 44 are switched. Both the nozzle 44 and the nozzle 55 are driven to a position where the nozzle opening faces the electrolyte membrane 7 when ink is ejected (applied). However, when ink is not ejected (applied), as shown in FIG. It rotates around the rotation axis and operates to stop at a position away from the electrolyte membrane 7.

  This time lag T is preferably as short as possible. This is because the boundary between the catalyst ink for the catalyst layer 5 and the resin ink for the seal portion 6 is easily dissolved and the exposure of the electrolyte membrane 7 can be prevented. For that purpose, it is preferable that the slits of the slit dies of the nozzles 22, 44, and 55 are brought close to each other (that is, L [m] is shortened), particularly at the time of applying each ink.

  If a minute exposed surface of the electrolyte membrane is generated at the boundary between the catalyst layer 5 and the seal portion 6 due to the presence of the time lag T, the viscosity of the resin ink and the catalyst ink is adjusted to be low, or the electrolyte membrane of both inks It can be eliminated by improving the wettability with respect to 7. Further, the nozzles 44 and 55 may be finely adjusted by the control means so that the resin ink 6 slightly overlaps the peripheral portion of the catalyst layer 5.

  Next, the MEA manufacturing method (manufacturing apparatus) described with reference to FIG. 1 or FIGS. 2 to 4 is included with reference to FIG. 5, and in addition, necessary post-process (required apparatus) is included. An apparatus 100 for forming a gas diffusion layer (GAS DIFFUSION LAYER: abbreviated as “GDL”) on the MEA and manufacturing a membrane-electrode-GDL assembly (MEMBRANE ELECTRODE GDL ASSEMBLY: abbreviated as “MEGA”) explain.

As shown in FIG. 5, the apparatus 100 is a roll-to-roll MEGA mass production apparatus, and is an electrolyte membrane 7 with a web-like carrier film 8 (hereinafter simply referred to as “ The electrolyte membrane 7 ”is wound around the unwinding roll 20 in advance, and the tip 7T of the electrolyte membrane 7 is fixed to the peripheral portion of the winding roll 30.
The MEA manufacturing apparatus (manufacturing process) of the coating apparatus 10 (or 100) described with reference to FIG. 1 or FIGS. 2 to 4 corresponds to a portion indicated by W. During the manufacturing process indicated by W, a certain amount of tension must be applied to the web-like electrolyte membrane 7 in order to smoothly apply (discharge) each ink to the web-like electrolyte membrane 7. Therefore, the web-like electrolyte membrane 7 is supported from below by the roll 11 that keeps the surface of the web-like electrolyte membrane 7 unwound by the unwinding roll 20, nipped by the nip rolls 12, 13, and the unwinding roll 20 and the nip roll 12, A constant tension is maintained between

  After this MEA manufacturing process (part indicated by W), the web-like electrolyte membrane 7 on which the MEA is formed is conveyed and enters the drying device 50. In the drying device 50, the catalyst ink of the catalyst layer 5 and the resin ink of the seal portion 6 are dried by a drying means such as warm air or an infrared heater, and the organic solvent and moisture of each ink are evaporated.

The web-like electrolyte membrane 7A formed with the MEA dried by the drying device 50 is further conveyed, but the GDL sheet 22 is wound from the GDL sheet unwinding roll 40 between the nip rolls 12 and 13 and the nip rolls 16 and 17. The web-like MEGA 7B is formed so as to be carried on the web-like electrolyte membrane 21 between the nip rolls 14 and 15.
The GDL sheet 22 contains a water-repellent resin, but in order to strengthen the bonding force between the web-like electrolyte membrane 21 and the GDL sheet 22, an adhesive application means 25 is provided at the illustrated position so that the web-like electrolyte membrane 21 and the GDL sheet are provided. Adhesive resin may be applied to the interface with 22.

  Thereafter, the web-like MEGA 7B is sandwiched between the nip rolls 16 and 17, but the nip rolls 16 and 17 also serve as a hot-pressure roll, and the GDL sheet 22 and the web-like MEA 7A are subjected to hot-pressure treatment to join them together.

  Here, the web-like MEGA 7B is manufactured, but it is necessary to further process into a single wafer state for assembly into a fuel cell (single cell). Therefore, MEGA is punched one by one from the web-like MEGA tape 22 by the cutting machines (punching machines) 60 and 61 while applying a constant tension to the web-like MEGA 7B by the nip rolls 16 and 17 and the nip rolls 18 and 19. The punched MEGA is provided in the cutting machine 60, and is inserted into a space 60H designed to have a horizontal cross-sectional dimension larger than the surface dimension of the MEGA one by one. Further, the MEGA is inserted from above the space 60H. Collect by an automatic machine such as a robot. The web 7C from which the MEGA is punched is wound around the winding roll 30.

  Thus, according to this embodiment, when MEA is manufactured as MEGA, it can be mass-produced by roll-to-roll, so that the manufacturing cost is reduced, and in recent years, the solid polymer form that is expected to be increasingly demanded in the future. It is possible to design a production line that can sufficiently meet the demand for fuel cells or direct methanol fuel cells.

  Note that the fuel cell membrane electrode assembly manufacturing apparatus and method according to the present invention are not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention. Of course.

  For example, when the transport speed U changes depending on the situation, the drive control (ON / OFF) of each slit die is performed by incorporating a system capable of calculating the time lag T (= L / U) in real time in the control means. You can also do it.

  Further, by omitting the apparatus (process) from the nip rolls 14 and 15 to the nip rolls 16 and 17 from the apparatus 100 shown in FIG. 5, the apparatus 100 can be used as a mass production line for MEA instead of MEGA.

  In the manufacturing method and the manufacturing apparatus according to the present embodiment and examples, the catalyst layer 5 and a seal portion surrounding the catalyst layer 5 in a ladder shape are formed on either the anode side or the cathode side of the electrolyte membrane 7. However, the catalyst film 5 and a seal portion surrounding the catalyst layer 5 in a ladder shape can be formed on both sides of the electrolyte film 7 without supporting the electrolyte film 7 on the carrier film 8. Further, the catalyst layer 5 and the seal portion surrounding the catalyst layer 5 in a ladder shape were manufactured on either the anode side or the cathode side of the electrolyte membrane 7 by the manufacturing method and manufacturing apparatus according to the present embodiment and examples. After that, the carrier film 8 is peeled off from the electrolyte membrane 7 and the electrolyte membranes 7 are joined back to back, so that the catalyst layer 5 and the seal portion MEA that surrounds the catalyst layer 5 in a ladder shape or GDL is joined to both sides. It is also possible to manufacture MEGA.

It is the schematic top view (a) and schematic sectional drawing (b) for demonstrating the manufacturing apparatus of MEA which concerns on this embodiment, and the said method. It is the schematic top view (a) and schematic sectional drawing (b) for demonstrating the MEA manufacturing apparatus which concerns on this embodiment, and the said method (especially using a slit die). It is a perspective view for demonstrating the structure of the ink discharge nozzle (thing using a slit die) 22 used with the manufacturing apparatus of MEA which concerns on this embodiment. It is each timing chart when driving each nozzle (slit die) 22, 44, 55 of the MEA manufacturing apparatus according to the present embodiment. A MEGA manufacturing apparatus including the MEA manufacturing apparatus.

Explanation of symbols

5: catalyst layer, 6: ladder-like seal portion, 7: web-like electrolyte membrane, 10, 150: ink coating device.

Claims (6)

A ladder-like seal portion provided with a long-side side portion and a ladder-like step portion perpendicular to the both side portions at a constant interval on the web-like electrolyte membrane, and a catalyst surrounded by a frame in the ladder-like seal portion A method for producing a membrane-electrode assembly in which a layer is formed,
A first step of forming the both side portions of the ladder-shaped seal portion by continuously applying the resin ink for the seal portion to the both side portions formed on the ladder-shaped seal portion being linearly conveyed. When,
The catalyst ink for forming the catalyst layer and the resin ink for the seal portion for forming the ladder-like step portion are respectively formed on the exposed portions of the electrolyte sandwiched between both sides of the ladder-like seal portion. A second step of periodically and alternately applying a constant width along the transport direction;
A method for producing a membrane-electrode assembly for a fuel cell, comprising:   The method for producing a membrane-electrode assembly for a fuel cell according to claim 1, wherein the first step and the second step are performed simultaneously. A ladder-like seal portion provided with a long-side side portion and a ladder-like step portion perpendicular to the both side portions at a constant interval on the web-like electrolyte membrane, and a catalyst surrounded by a frame in the ladder-like seal portion An apparatus for producing a membrane-electrode assembly that forms a layer,
An ink application device for applying a catalyst ink and a resin ink for forming a ladder seal to the web-like electrolyte membrane;
The ink application device applies the ladder-sealed-portion-forming resin ink and the catalyst ink to the web-shaped electrolyte membrane conveyed in a straight line so that the ladder-shaped seal portion surrounds the catalyst layer in a frame shape. An apparatus for producing a membrane-electrode assembly for a fuel cell, comprising control means for controlling the fuel cell to form. The ink application apparatus includes first, second, and third ink ejection means whose ejection operations are controlled by the control means,
The first, second and third ink ejection means are arranged on the electrolyte membrane in substantially the same plane, and
The resin ink is ejected to the first ink ejection means toward the electrolyte membrane corresponding to the both sides of the ladder frame of the seal portion, and the second ink ejection means and the third ink ejection means The control means outputs to the first, second and third ink ejection means a command for ejecting the catalyst ink and the resin ink toward the electrolyte alternately at a constant cycle. The manufacturing apparatus according to claim 3, wherein:   The first, second and third ink discharge means have a slit die, the slit die includes a slit-like discharge port for discharging each ink to the electrolyte film, and the slit die of the slit die is long. The manufacturing apparatus according to claim 4, wherein a direction is set to be perpendicular to the conveyance direction. The first ink ejecting means has two slit dies capable of ejecting the resin ink perpendicularly to the electrolyte membrane from the slit dies, and a fixed length for connecting the two slit dies apart. The vertical cross section consisting of a support member has a structure of a reverse concave part,
The fixed length of the support member is equal to or longer than the length of the catalyst layer in the direction perpendicular to the transport direction, and the height of the support member is set at a position higher than the top surface of the catalyst layer. The manufacturing apparatus according to claim 5, wherein:

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