JP2017073262A - Method and device for manufacturing fuel cell - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and device for manufacturing a fuel cell, preventing manufacturing cost from being deteriorated by suppressing a large amount of defective products from being manufactured, the defective products being deposited with a film thickness different from a desired film thickness.SOLUTION: A method for manufacturing a fuel cell includes a surface treatment step S5 for subjecting a plate-like base material 123 to surface treatment. During the surface treatment step, a film is continuously formed on a surface of the base material in a vacuum furnace 101, the base material is conveyed after the formation of the film, and the thickness of the film is measured continuously with the formation of the film on a downstream side in a conveyance direction.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a fuel cell manufacturing method and a fuel cell manufacturing apparatus.

  Conventionally, various proposals for producing a fuel cell with high productivity have been made. For example, in the invention described in Patent Document 1, a fuel cell is continuously manufactured by performing various treatments on a long base material serving as a separator while being pulled out from a roll and conveyed.

  One of those processes applied to the separator is film formation. By forming a film made of metal, DLC (diamond-like carbon), or the like on the surface of the separator, conductivity and corrosion resistance can be improved. Since such characteristics vary depending on the film thickness, it is important to manage the film thickness.

Japanese Patent No. 4529439

  However, in the above-described prior art, the film thickness is not inspected, and even if a film having a desired thickness is not formed, the production is continued in that state. As a result, defective products are manufactured in large quantities, which may lead to deterioration in manufacturing costs.

  In addition, even if the film thickness is inspected offline after continuously forming the film on all the substrates for one roll, the film thickness is not inspected until the film formation for one roll is completed. There is a risk that a defective product having a film thickness different from the above will be produced in large quantities.

  This invention is made | formed in view of such a subject, suppresses that a defective product formed into a film with a film thickness different from a desired film thickness is manufactured in large quantities, and prevents deterioration of manufacturing cost. It is an object of the present invention to provide a fuel cell manufacturing method and a fuel cell manufacturing apparatus.

  In order to achieve the above object, a method for producing a fuel cell of the present invention includes a surface treatment step of performing a surface treatment on a plate-like substrate. In the surface treatment process, a film is continuously formed on the surface of the base material in the vacuum furnace, and the base material is transported following the formation of the film. The thickness is measured.

  In order to achieve the above object, a fuel cell manufacturing apparatus of the present invention has a surface treatment apparatus for performing a surface treatment on a plate-like substrate. The surface treatment apparatus includes a vacuum furnace provided with a transport path for the base material, a film forming apparatus for continuously forming a film on the surface of the base material facing the transport path in the vacuum furnace, and a film A film thickness measuring device for measuring the thickness of the film. The film thickness measuring device is disposed facing the transport path that continues downstream in the transport direction of the substrate with respect to the film forming device.

  According to the present invention, since the film thickness is measured continuously with the formation of the film on the surface of the substrate, a film thickness defect is quickly discovered. Therefore, it is difficult to manufacture a large number of defective products having a film thickness different from the desired film thickness, and the present invention can prevent the manufacturing cost from deteriorating.

It is a figure which shows schematic structure of the manufacturing apparatus of the fuel cell of embodiment. It is a flowchart which shows the outline of the manufacturing method of the fuel cell of embodiment. It is a perspective view which shows the separator shape | molded by the elongate board | plate material. FIG. 4 is a cross-sectional view taken along line 4-4 of FIG. It is a perspective view of a separator zygote. It is a flowchart which shows the outline of the surface treatment process of embodiment. It is a perspective view which shows film thickness measurement. It is a flowchart which shows control of the apparatus based on the measurement result of a film thickness. It is a figure which shows the example of the change of the film thickness along a measurement locus. ^A * in the quality and ^{the L} * ^a * ^{b *} color space of the contact resistance is a diagram showing the relationship between ^{b *.} It is a flowchart which shows control of the apparatus based on the determination result of contact resistance. It is a perspective view of the separator assembly and membrane electrode assembly which are laminated alternately. It is a perspective view of a fuel cell main body. It is a figure which shows schematic structure of the manufacturing apparatus of the fuel cell of a modification.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, the dimension ratio of drawing is exaggerated on account of description, and differs from an actual ratio.

  As shown in FIG. 1, the fuel cell manufacturing apparatus 10 according to the embodiment includes a forming apparatus 140, a welding apparatus 150, a cleaning apparatus 160, a cutting apparatus 170, a surface treatment apparatus 100, and an adhesive application apparatus 180. And a drying furnace 190.

  The forming apparatus 140 includes a roller 141 that presses with a long plate member 121 interposed therebetween. The molding apparatus 140 press-molds the plate material 121 to form the separator 122. The outer peripheral surface of the roller 141 is provided with an uneven shape corresponding to the outer surface shape of the separator 122. The plate material 121 is drawn out from the roll 120 around which the plate material 121 is wound, and is continuously supplied.

  The material for forming the plate 121 is, for example, a stainless steel plate or an improved steel plate in which the main component composition of iron, nickel, and chromium is appropriately changed.

  The welding apparatus 150 irradiates the laser 151 to weld the separators 122 to each other. The welding apparatus 150 only needs to be able to join the separators 122 to each other, and is not limited to the form in which the welding is performed by the laser 151.

  The cleaning device 160 irradiates the laser 161 to clean the surface of the separator 122. The cleaning device 160 only needs to be able to clean the surface of the separator 122, and is not limited to a form in which the surface is cleaned by the laser 161.

  The cutting device 170 is, for example, a shear type cutting machine. Cutting device 170 cuts what welded separator 122, and forms separator zygote 123 (base material). The cutting device 170 is not limited to a shear type cutting machine as long as it can cut the welded separator 122.

  The surface treatment apparatus 100 includes a vacuum furnace 101, a pump 102 that communicates with the vacuum furnace 101, and a cylinder 103 that communicates with the vacuum furnace 101. The surface treatment apparatus 100 includes a conveyor 104 that conveys the separator assembly 123. The surface treatment apparatus 100 includes an electrode 105, a sputtering source 106, a sputtering source 107 (film forming apparatus), a spectrometer 108 (film thickness measuring apparatus), and a camera 109 (image recognition apparatus). These are arranged facing the conveyance path formed by the conveyor 104, and are arranged in this order from the upstream side to the downstream side in the workpiece conveyance direction. The surface treatment apparatus 100 includes a lighting device 110. The surface treatment apparatus 100 includes a control device 111 that controls the operation of the components.

  The vacuum furnace 101 accommodates a conveyor 104, an electrode 105, a sputtering source 106, a sputtering source 107, and a spectrometer 108. The electrode 105, the sputter source 106, the sputter source 107, and the spectrometer 108 are each partitioned by a wall. The camera 109 is disposed outside the vacuum furnace 101.

The pump 102 exhausts gas from the inside of the vacuum furnace 101. The degree of vacuum inside the vacuum furnace 101 is, for example, about 10 ⁻³ Pa. The cylinder 103 supplies an inert gas such as argon into the vacuum furnace 101.

  The electrode 105 has a flat plate shape. The electrode 105 is electrically connected to a power source (not shown). When a voltage is applied to the electrode 105 in the inert gas, plasma is generated between the separator assembly 123 on the conveyor 104 and the electrode 105, and the inert gas is ionized.

  The sputter source 106 includes a target formed of chromium. The sputtering source 106 applies a voltage (hereinafter referred to as a sputtering voltage) to the target in an inert gas, and deposits particles from the target toward the workpiece to form a film.

  The material for forming the target included in the sputtering source 106 is not limited to chromium, but may be nickel, zinc, copper, tungsten, titanium, cobalt, molybdenum, zirconium, hafnium, vanadium, or the like.

  The sputter source 107 includes a target formed of carbon. The sputtering source 107 forms a film by applying a sputtering voltage to a target made of carbon in an inert gas and repelling particles from the target toward the workpiece.

  The thickness of the formed film is measured in the vacuum furnace 101 by the spectrometer 108. The spectrometer 108 includes a light projecting unit that emits light toward the separator assembly 123 on the conveyor 104, and a light receiving unit that receives light reflected from the workpiece. The spectrometer 108 includes a light source that is optically connected to the light projecting unit. The light source is, for example, a halogen lamp and a blue LED. The spectrometer 108 separates the light received by the light receiving unit. The spectrometer 108 includes, for example, a photodiode or a photomultiplier tube, and outputs an output signal corresponding to the intensity of the separated light to the control device 111. The spectrometer 108 and the control device 111 are electrically connected.

  The camera 109 images the separator assembly 123 on the conveyor 104. The separator assembly 123 imaged by the camera 109 is illuminated by the lighting device 110. The illumination device 110 is a halogen lamp, for example. The camera 109 is electrically connected to the control device 111.

  The camera 109 and the lighting device 110 are disposed outside the vacuum furnace 101. The camera 109 images the separator assembly 123 through the window 112 provided in the vacuum furnace 101. The illumination device 110 illuminates the separator assembly 123 through a window 113 provided in the vacuum furnace 101. The windows 112 and 113 are made of glass, for example.

  The control device 111 is a computer such as a personal computer and an engineering workstation.

  The control device 111 controls the work conveyance speed by the conveyor 104. The control device 111 controls the voltage applied to the electrode 105. The control device 111 controls the sputtering voltage of the sputtering source 106. Thereby, the property of the intermediate layer formed on the separator assembly 123 is controlled. The control device 111 controls the sputtering voltage of the sputtering source 107. This controls the properties of the film formed on the intermediate layer.

  The control device 111 calculates the film thickness of the film formed on the separator assembly 123 based on the reflected light from the separator assembly 123 received by the spectrometer 108. The calculation method of the film thickness is spectroscopic ellipsometry in which the film thickness is calculated from the change in the polarization state between the incident light on the separator assembly 123 and the reflected light from the separator assembly 123.

The control device 111 calculates each value of L ^* , a ^* , and b ^{* in} the L ^* a ^* b ^* color space from the surface image of the separator assembly 123 captured by the camera 109. L ^* represents lightness. a ^* and b ^* represent chromaticity. The L ^* a ^* b ^* color space and L ^* , a ^* , b ^* are defined in JIS Z8781-4: 2013.

  The adhesive application device 180 applies the adhesive 181 to the separator assembly 123 by screen printing. The adhesive application device 180 includes a screen 182 in which a hole through which the adhesive 181 passes is formed, and a squeegee 183 that slides on the surface of the screen 182. The adhesive applicator 180 only needs to be able to apply the adhesive 181 to the separator assembly 123, and is not limited to a form in which the adhesive 181 is applied by screen printing.

  The fuel cell manufacturing apparatus 10 includes a robot arm (not shown) that alternately stacks separator assemblies 123 and membrane electrode assemblies 124 (hereinafter referred to as MEAs 124).

  Next, a method for manufacturing a fuel cell will be described.

  As shown in FIG. 2, the fuel cell manufacturing method of the embodiment includes a forming step S1, a welding step S2, a cleaning step S3, and a cutting step S4. The fuel cell manufacturing method includes a surface treatment step S5, an adhesive application step S6, and a modularization step S8. The fuel cell manufacturing method includes an MEA frame roughening step S7 for roughening the MEA frame before the modularization step S8. The fuel cell manufacturing method includes an adhesive curing step S9, a leak inspection step S10, a stacking step S11, a load adjustment spacer selection step S12, a main body assembly step S13, and a performance measurement step S14.

  As shown in FIG. 3, in the molding step S1, the separator 122 in which the groove-shaped flow path 122a and the manifolds 122b and 122c which are through holes are formed is molded. The plurality of separators 122 are formed in a continuous state. When the roller 141 (FIG. 1) presses the plate material 121, the flow path 122a and the manifolds 122b and 122c are formed. In each separator 122, any one of the plurality of manifolds 122b communicates with the flow path 122a. In each separator 122, any one of the plurality of manifolds 122c communicates with the flow path 122a.

  After the molding step S1, the separator 122 and the separator 122 are overlapped and welded in the welding step S2 (FIG. 1).

  As shown in FIG. 4, in the welding step S <b> 2, a laser 151 (FIG. 1) is irradiated to a portion 122 e where the flow paths 122 a are joined together, and the separators 122 are welded together.

  In the cleaning step S3, the surface of the separator 122 is irradiated with a laser 161 (FIG. 1), and is degreased and cleaned.

  As shown in FIG. 5, in the cutting step S <b> 4, a portion between the separator 122 and the separator 122 in the longitudinal direction is cut, and a separator assembly 123 in which the single separators 122 are overlapped and joined is formed. Thereafter, the separator assembly 123 is subjected to a surface treatment in the surface treatment step S5 (FIG. 1).

  As shown in FIG. 6, the surface treatment step S5 includes a vacuuming step S101, a heating step S102, a bombarding step S103, an intermediate layer forming step S104, a film forming step S105, a film thickness measuring step S106, a contact resistance determining step S107, and And returning to the atmosphere S108. These processes are executed by the surface treatment apparatus 100.

  In the evacuation step S101, the pump 102 evacuates the vacuum furnace 101 while the vacuum furnace 101 is sealed. A plurality of separator assemblies 123 are placed in the vacuum furnace 101 before the vacuuming step S101. These separator assemblies 123 are placed one by one at a predetermined interval on the end of the conveyor 104 by a robot arm (not shown) provided in the vacuum furnace 101, for example.

  Each separator assembly 123 is conveyed by the conveyor 104 and sequentially passes through the electrode 105, the sputtering source 106, the sputtering source 107, the spectrometer 108, and the camera 109. When each separator assembly 123 passes through each of them, a bombarding step S103, an intermediate layer forming step S104, a film forming step S105, a film thickness measuring step S106, and a contact resistance determining step S107 are performed.

  In the heating step S102, the separator assembly 123 is heated from the end of the conveyor 104 until it reaches the position facing the electrode 105. The separator assembly 123 is heated in a non-contact manner, for example, by radiation. Alternatively, the separator assembly 123 is heated by, for example, contact with a roller incorporating a heater.

  In the bombard process S103, the inert gas ionized by the voltage application to the electrode 105 strikes the surface of the separator assembly 123, and the oxide film on the surface of the separator assembly 123 is removed. At this time, a bias voltage may be applied to the separator assembly 123. By doing so, since the ionized inert gas is guided toward the separator assembly 123, the etching effect is increased.

  The bias voltage is applied to the separator assembly 123 by, for example, sliding a conductive brush (not shown) electrically connected to a power source on the surface of the separator assembly 123 being conveyed.

  In the intermediate layer formation step S <b> 104, an intermediate layer is formed on the surface of the separator assembly 123 by physical vapor deposition (PVD: Physical Vapor Deposition). When the separator assembly 123 is conveyed while facing the sputtering source 106, particles ejected from the target in the sputtering source 106 collide with the separator assembly 123, and an intermediate layer is formed.

  In the film forming step S105, a film is formed on the separator assembly 123 by physical vapor deposition (PVD). When the separator assembly 123 is transported while facing the sputtering source 107, particles ejected from the target in the sputtering source 107 collide with the separator assembly 123, and a film is formed. The film is formed on the intermediate layer. The material for forming the film is diamond like carbon (DLC). The film has electrical conductivity and corrosion resistance. When the separator assembly 123 faces the sputtering source 107, a bias voltage is applied to the separator assembly 123. As a result, the particles ejected from the sputtering source 107 are attracted toward the separator assembly 123. By controlling the bias voltage applied to the separator assembly 123, the properties of the formed film are controlled.

  The physical vapor deposition method performed in the intermediate layer forming step S104 and the film forming step S105 is, for example, high-power impulse magnetron sputtering (HIPIMS). The physical vapor deposition method is not limited to HIPIMS, and may be other sputtering method or ion beam deposition.

  As shown in FIG. 7, in the film thickness measurement step S <b> 106, the spectrometer 108 moves in a direction D <b> 2 that intersects the transport direction D <b> 1 in the surface direction of the separator assembly 123. Thus, by moving the spectrometer 108 and transporting the separator assembly 123, the thickness of the film is measured obliquely with respect to the transport direction D1.

  More specifically, the light from the spectrometer 108 striking the separator assembly 123 moves relative to the diagonal L of the separator assembly 123 from one end L1 to the other end L2, and the film thickness at the diagonal L is measured. Is done. The measured film thickness is the film thickness of the DLC film formed on the intermediate layer. The spot diameter of light striking the separator assembly 123 is, for example, about 500 nm.

  When the measurement of the film thickness for one separator assembly 123 is completed and the thickness of the separator assembly 123 conveyed next is measured, the spectrometer 108 moves in the direction D3 opposite to the direction D2. At this time, the light striking the separator joined body 123 relatively moves on another diagonal line of the separator joined body 123 intersecting the diagonal line L. The direction D1 is orthogonal to the directions D2 and D3.

  A driving device 114 connected to the spectrometer 108 moves the spectrometer 108. The driving device 114 moves the spectrometer 108 by rotating, for example, a ball screw connected to the spectrometer 108 with a motor.

  The movement of the spectrometer 108 by the driving device 114 is controlled by the control device 111. Further, the control device 111 determines the measured film thickness, and controls the sputtering voltage of the sputtering source 107 or the bias voltage applied to the separator assembly 123 based on the result.

  As shown in FIG. 8, after film formation S1001 and film thickness measurement S1002, it is determined whether or not the film thickness is within specifications (S1003). Thereafter, it is determined whether or not the film thickness is within a range that does not require correction (S1004). The film formation S1001 in FIG. 8 corresponds to the film formation process S105 in FIG. 6, and the film thickness measurement S1002 corresponds to the film thickness measurement process S106 in FIG.

  In step S1003 for determining whether or not the film thickness is within the standard, it is determined whether or not the measured film thickness is between the upper limit standard value V1 and the lower limit standard value V2, as shown in FIG. . When the measured film thickness is outside the standard, specifically, when the measured film thickness is thick and larger than the upper limit standard value V1, or when the measured film thickness is thin and smaller than the lower limit standard value V2, the control device 111 stops the operation of the surface treatment apparatus 100 and stops the film formation (S1005 in FIG. 8).

  In determination S1004 whether or not the film thickness is in a range that does not require correction, it is determined whether or not the measured film thickness is between the correction-unnecessary upper limit value V3 and the correction-unnecessary lower limit value V4.

  When the measured film thickness is in the range that does not require correction between the correction-unnecessary upper limit value V3 and the correction-unnecessary lower limit value V4, the control device 111 maintains the sputtering voltage of the sputtering source 107.

  When the measured film thickness is larger than the correction unnecessary upper limit value V3 and is within the correction range between the correction unnecessary upper limit value V3 and the upper limit standard value V1, the control device 111 adjusts the sputtering voltage of the sputtering source 107, The measured film thickness is set to be equal to or less than the correction unnecessary upper limit value V3 (S1006 in FIG. 8).

  When the measured film thickness is smaller than the correction unnecessary lower limit value V4 and is within the correction range between the correction unnecessary lower limit value V4 and the lower limit standard value V2, the control device 111 adjusts the sputtering voltage of the sputtering source 107, The film thickness is set to be not less than the correction unnecessary lower limit value V4 (S1006 in FIG. 8).

  The adjustment of the voltage performed in S1006 in FIG. 8 may be adjustment of the bias voltage applied to the separator assembly 123.

  The film thickness measurement S1002 and the film thickness determinations S1003 and S1004 are continuously performed until the light from the spectrometer 108 moves relative to the diagonal L and reaches the end L2 (S1007 in FIG. 8). Thereafter, the separator assembly 123 is continuously conveyed, and the next step, the contact resistance determination step S107 (FIG. 6), is performed.

  In the contact resistance determination step S107, the surface image of the conveyed separator assembly 123 is captured by the camera 109, and the quality of the contact resistance of the formed separator assembly 123 is determined based on the captured surface image. In the contact resistance determination step S107, the sputtering voltage of the sputtering source 107 is controlled based on the determination result. Here, the bias voltage applied to the separator assembly 123 may be adjusted.

  The surface image of the separator assembly 123 captured by the camera 109 is sent to the control device 111. The control device 111 functions as a determination device that determines contact resistance based on the surface image of the separator assembly 123.

The control device 111 calculates each of L ^* , a ^* , b ^{* in} the L ^* a ^* b ^* color space from the surface image of the separator assembly 123, and the calculated color coordinates (L ^* , a ^* , b). ^* ) Is determined to be good if it is in a predetermined area in the L ^* a ^* b ^* color space, and is determined to be poor if it is in another area different from that area. To do.

For example, FIG. 10 shows the a ^* -b ^* plane at a predetermined L ^* calculated from the surface image. In this example, when the color coordinates (a ^* , b ^* ) calculated from the surface image are in the hatched area indicated by the symbol NG in FIG. 10, the control device 111 determines that the contact resistance is defective. . On the other hand, when the color coordinates (a ^* , b ^* ) calculated from the surface image are in the area indicated by the symbol OK in FIG. 10, which is the other area, the control device 111 has good contact resistance. Is determined.

Calculated color coordinates ^(a *, ^{b *)} is, when in the region of the code NG in FIG. 10, the contact resistance, for example, greater than 5mΩ ^· cm 2 / 1MPa. Calculated color coordinates ^(a *, ^{b *)} is, when in the region of the code OK in FIG. 10, the contact resistance is, for example, less 5mΩ ^· cm 2 / 1MPa.

The operator preliminarily converts the relationship between the L ^* a ^* b ^* color space and the contact resistance into data, and the region in the L ^* a ^* b ^* color space where the contact resistance is determined to be good, and the contact resistance. A region in the L ^* a ^* b ^* color space where it is determined that is defective is determined. The control device 111 stores these. The control device 111 stops the facility or adjusts the sputtering voltage of the sputtering source 107 based on the determination result of the contact resistance.

  Specifically, as shown in FIG. 11, after the film formation S1011 and the surface image recognition S1012 by the camera 109, the control device 111 determines whether or not the contact resistance is within the standard and determines whether or not to stop the equipment. Determine (S1013). Further, the control device 111 determines whether or not the contact resistance is in a range that does not require correction, and determines whether or not to adjust the sputtering voltage (S1014).

  The film formation S1011 in FIG. 11 corresponds to the film formation process S105 in FIG. 6, and the processes indicated by reference numerals S1012 to S1016 in FIG. 11 correspond to the contact resistance determination process S107 in FIG.

  In S1013 of FIG. 11, when the contact resistance is within the standard (YES), the facility operates continuously. The case where the contact resistance is within the standard is, for example, a case where the calculated color coordinates are present in the area of reference OK in FIG.

  On the other hand, in S1013 of FIG. 11, when the contact resistance is out of specification (NO), the control device 111 stops the equipment (S1015). The case where the contact resistance is out of the standard is, for example, a case where the calculated color coordinate is in the area of NG in FIG.

  Although not shown in FIG. 10, the operator previously determines a range in which the contact resistance is not required to be corrected and a range in which the correction is required in FIG. When the calculated color coordinate is in a range where the contact resistance does not need to be corrected, the control device 111 does not adjust the sputtering voltage of the sputtering source 107 (YES in S1014 in FIG. 11). On the other hand, when the calculated color coordinates are within a range where the contact resistance needs to be corrected, the control device 111 adjusts the sputtering voltage of the sputtering source 107 (reference S1016 in FIG. 11). A desired contact resistance is obtained by adjusting the sputtering voltage. A desired contact resistance may be obtained by adjusting the bias voltage applied to the separator assembly 123.

  After the processes of S102 to S107 shown in FIG. 6 are performed on a predetermined number of separator assemblies 123 by the surface treatment apparatus 100 (FIG. 1), the atmosphere returning process S108 is performed.

  In the atmosphere returning step S108, gas is introduced into the vacuum furnace 101 in a vacuum state, and the vacuum state in the vacuum furnace 101 is released. Thereafter, the formed separator assembly 123 is taken out from the vacuum furnace 101, and an adhesive 181 is applied in an adhesive application step S6 (FIGS. 1 and 2), which is the next step.

  In the adhesive application step S <b> 6, for example, the adhesive 181 is applied to the outer peripheral portions of both surfaces of the separator assembly 123. Thereafter, a modularization step S8 is performed (FIG. 2).

  As shown in FIG. 12, in the modularization step S8, the separator assembly 123 and the MEA 124 are alternately stacked. A single cell 126 that is the smallest unit of a fuel cell has a configuration in which an MEA 124 is sandwiched between separator assemblies 123. The module 125 (FIG. 1) has a configuration in which a plurality of single cells 126 are stacked and electrically connected.

  The MEA 124 includes an electrolyte membrane 124a, electrodes 124b formed on both surfaces of the electrolyte membrane 124a, and a frame 124c disposed around the electrodes 124b on both surfaces of the electrolyte membrane 124a.

  The electrolyte membrane 124a is a proton conductive ion exchange membrane formed of a solid polymer material, for example, a fluorine resin, and exhibits good electrical conductivity in a wet state. The electrode 124b has a configuration in which a gas diffusion layer is formed on the catalyst layer. The catalyst layer of the electrode 124b formed on one surface of the electrolyte membrane 124a includes a catalyst component that has a catalytic action on the oxygen reduction reaction. The catalyst layer of the electrode 124b formed on the other surface of the electrolyte membrane 124a contains a catalyst component that has a catalytic action on the oxidation reaction of hydrogen. The gas diffusion layer provided on the catalyst layer has conductivity and gas diffusibility. The gas diffusion layer is made of, for example, a wire mesh.

  The frame 124c is roughened in advance before the modularization step S8 in the MEA frame roughening step S7 (FIG. 2). The frame 124c is roughened by irradiating the surface with laser or plasma. The material forming the frame 124c is, for example, resin.

  In the adhesive curing step S9, the module 125 (FIG. 1) is accommodated in the drying furnace 190 at a predetermined temperature for a predetermined time, and the adhesive 181 applied to the separator assembly 123 is dried. By drying the adhesive 181, the separator assembly 123 and the MEA 124 that are adjacent to each other adhere to each other. After drying, the module 125 is removed from the drying furnace 190.

  In the leak inspection step S10 (FIG. 2), the operator flows gas through the module 125 and inspects for gas leakage.

  As shown in FIG. 13, in the stacking step S11 (FIG. 2), a plurality of modules 125 are stacked to form a stack 127. The plurality of stacked modules 125 are electrically connected.

  A current collecting plate 131 having conductivity is disposed outside both ends of the stack 127 in the stacking direction of the modules 125. The current collector 131 is electrically connected to the stack 127. An end plate 130 insulated from the current collector 131 is disposed outside the current collector 131. The pair of end plates 130 sandwich the stack 127. The pair of end plates 130 are fastened by a side plate 134 that covers the periphery of the stack 127 and holds the stack 127.

  The end plate 130 is provided with a supply port 130 a for supplying fuel gas to the stack 127 and a discharge port 130 b for discharging the fuel gas that has passed through the stack 127.

  The end plate 130 is provided with a supply port 130 c for supplying an oxidant gas to the stack 127 and a discharge port 130 d for discharging the oxidant gas that has passed through the stack 127.

  The end plate 130 is provided with a supply port 130e for supplying a cooling fluid to the stack 127 and a discharge port 130f for discharging the cooling fluid that has passed through the stack 127.

  An output terminal 133 for extracting power from the stack 127 protrudes from the end plate 130. The output terminal 133 is electrically connected to the current collector 131.

  In the load adjustment spacer selection step S12 (FIG. 2), the spacer 132 disposed between the end plate 130 and the current collector 131 is selected. The load applied to the stack 127 from the stacking direction when the pair of end plates 130 are fastened by the side plates 134 is adjusted by the thickness of the spacer 132.

  In the main body assembly step S13 (FIG. 2), the pair of end plates 130 are fastened by the side plates 134, and the fuel cell main body is completed.

  Thereafter, in the performance measurement step S14 (FIG. 2), the power generation performance of the manufactured fuel cell main body is measured. The measurement of the power generation performance is performed by replacing the nitrogen gas with an oxidant gas such as air after aging, for example, by flowing hydrogen gas and nitrogen gas through the manufactured fuel cell body and operating for a while under the same conditions as the power generation operation.

  Next, the function and effect of this embodiment will be described.

  According to this embodiment, since the film thickness is measured continuously with the formation of the film on the surface of the separator assembly 123, a film thickness defect is quickly discovered. Therefore, it is difficult to manufacture a large number of defective products having a film thickness different from the desired film thickness, and this embodiment can prevent the manufacturing cost from deteriorating.

  In the present embodiment, the spectrometer 108 is disposed in the vacuum furnace 101 and measures the film thickness. There is no air convection in the vacuum furnace 101, and temperature change is suppressed. For this reason, the measurement accuracy by the spectrometer 108 is unlikely to vary. As a result, stable measurement can be continuously performed, which contributes to securing an appropriate film thickness. By ensuring an appropriate film thickness, abnormal performance deterioration during use of the fuel cell is prevented, and quality is maintained.

  In the present embodiment, the spectrometer 108 moves relative to the transport direction D1 of the separator assembly 123 so as to intersect (FIG. 7), and the film thickness is measured obliquely with respect to the transport direction D1 of the separator assembly 123. . By such an operation, it is possible for one spectrometer 108 to measure the film thickness in the directions D2 and D3 intersecting the transport direction D1. Unlike the present embodiment, when a plurality of spectrometers 108 are arranged in the directions D2 and D3 intersecting the transport direction D1, and the film thickness is measured, the plurality of spectrometers 108 are provided, so that the vacuum furnace 101 is enlarged. However, in this embodiment, since one spectrometer 108 moves and measures the film thickness, the size of the vacuum furnace 101 can be suppressed. By suppressing the size of the vacuum furnace 101, the time required for evacuation, and hence the lead time for the surface treatment, is shortened, so that the manufacturing cost can be suppressed.

  The contact resistance of the formed separator assembly 123 is, for example, about 1 to 10 mΩ and is very small. For this reason, unlike the present embodiment, if the contact resistance is measured by bringing the measurement terminal into direct contact with the surface of the separator assembly 123, the influence of temperature or contact pressure becomes significant, and the measurement results vary. Therefore, it is difficult to determine the contact resistance by bringing the measurement terminal into direct contact with the surface of the workpiece in-line. In addition, once film formation is completed for all the workpieces, and then the resistance is determined by bringing the measurement terminal directly into contact with the surface of the workpiece offline, if a defect occurs during film formation, Good products are manufactured. As a result, the manufacturing cost is deteriorated.

  In contrast, in the present embodiment, the contact resistance is determined in a non-contact manner based on the surface image of the separator assembly 123, so that the contact resistance can be determined in-line without being affected by the contact pressure or the like. As a result of the contact resistance being continuously determined in-line with the film formation, if a failure occurs in the contact resistance, the failure is promptly discovered. Therefore, defective products can be suppressed and manufacturing costs can be suppressed.

  In addition, since the contact resistance can be determined in-line, for example, it is possible to eliminate the trouble of moving the workpiece to another location and setting it in the determination device for determining the contact resistance, such as offline. Time can be shortened.

  Since the camera 109 is disposed outside the vacuum furnace 101 and the separator assembly 123 is imaged from there, there is no need for a space for disposing the camera 109 in the vacuum furnace 101. Therefore, the size of the vacuum furnace 101 can be suppressed. As a result, the time required for evacuation, and hence the lead time for the surface treatment, is shortened, so that the manufacturing cost can be suppressed.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, the surface treatment is not limited to that performed on the plurality of separator assemblies 123 conveyed as in the above embodiment.

  As shown in FIG. 14, the surface treatment step S <b> 5 of the above embodiment may be performed on a long plate-like substrate 201 while being conveyed by roll-to-roll. In FIG. 14, the same components as those shown in FIG. 1 are denoted by the same reference numerals as those in FIG.

  In the form shown in FIG. 14, the base material 201 is supplied while being drawn out from the roll 202 around which the base material 201 is wound, and after being surface-treated, the base material 201 is wound up by the roll 203. Thereafter, the roll 203 is taken out from the vacuum furnace 101 and used as the roll 120 shown in FIG. Thereafter, steps other than the surface treatment step S5 shown in FIG. 2 are performed in the same manner as in the above embodiment, whereby a fuel cell is manufactured. That is, in the flowchart shown in FIG. 2, the surface treatment step S5 is performed before the molding step S1. The processing performed in each step of the fuel cell manufacturing method and the order of the steps are not limited to the above embodiment.

  The material of the film formed on the substrate is not limited to DLC, but includes a film formed of other materials such as gold.

  In addition, the present invention includes a form in which the camera 109 is disposed upstream of the spectrometer 108 in the workpiece conveyance direction. In this case, the contact resistance is determined before the film thickness measurement.

10 Fuel cell manufacturing equipment,
100 surface treatment equipment,
101 vacuum furnace,
102 pump,
103 cylinder,
104 conveyor,
105 electrodes,
106 Sputter source,
107 Sputter source (film forming device),
108 Spectrometer (film thickness measuring device),
109 camera (image recognition device),
110 lighting device,
111 control device (determination device),
112, 113 windows,
114 drive device,
120 rolls,
121 board,
122 separator,
123 separator assembly (base material),
124 membrane electrode assembly (MEA),
125 modules,
126 single cell,
127 stacks,
130 end plate,
131 current collector,
132 spacers,
133 output terminal,
134 side plates,
140 molding equipment,
150 welding equipment,
160 cleaning equipment,
170 cutting device,
180 adhesive applicator,
190 drying oven,
200 surface treatment equipment,
201 substrate,
D1 transport direction,
D2, D3 The direction intersecting the transport direction,
L diagonal,
L1, L2 Diagonal ends.

Claims (10)

It has a surface treatment process for applying a surface treatment to a plate-shaped substrate,
In the surface treatment step, a film is continuously formed on the surface of the base material in a vacuum furnace, the base material is transported following the formation of the film, and the film is formed on the downstream side in the transport direction. A method for producing a fuel cell, wherein the thickness of the membrane is continuously measured.   The method for manufacturing a fuel cell according to claim 1, wherein the thickness of the film is measured by a spectrometer in the vacuum furnace.   The thickness of the film is measured obliquely with respect to the transport direction of the base material by the relative movement of the spectrometer so as to intersect the transport direction of the base material in the surface direction of the base material. Item 3. A method for producing a fuel cell according to Item 2. In the surface treatment step, a surface image of the substrate conveyed following the formation of the film is captured, and the film is formed from color coordinates corresponding to the surface image in the L ^* a ^* b ^* color space. The method for manufacturing a fuel cell according to any one of claims 1 to 3, wherein whether the contact resistance of the substrate is good or bad is determined.   The method for manufacturing a fuel cell according to claim 4, wherein the surface image of the base material is taken from outside the vacuum furnace. It has a surface treatment device that performs surface treatment on a plate-shaped substrate,
The surface treatment apparatus is
A vacuum furnace provided with a transport path for the substrate;
A film forming apparatus for continuously forming a film on the surface of the substrate, which is disposed facing the transport path in the vacuum furnace;
A film thickness measuring device for measuring the thickness of the film, which is arranged facing the transport path following the transport direction downstream side of the base material with respect to the film forming device,
An apparatus for manufacturing a fuel cell.   The apparatus for manufacturing a fuel cell according to claim 6, wherein the film thickness measuring device includes a spectrometer and is disposed in the vacuum furnace.   The spectrometer is provided so as to be relatively movable so as to intersect the transport direction of the base material in the surface direction of the base material, and measures the thickness of the film obliquely with respect to the transport direction of the base material. Item 8. The fuel cell manufacturing apparatus according to Item 7. An image recognition device disposed facing the transport path following the downstream side in the transport direction of the substrate with respect to the film forming device, and a determination device electrically connected to the image recognition device,
The image recognition device captures a surface image of the substrate on which the film is formed, and the determination device forms the film from color coordinates corresponding to the surface image in an L ^* a ^* b ^* color space. The apparatus for manufacturing a fuel cell according to any one of claims 6 to 8, wherein the quality of the contact resistance of the base material is determined.   The method of manufacturing a fuel cell according to claim 9, wherein the image recognition device is disposed outside the vacuum furnace.