JP2013237761A - Method for producing tab line with adhesive, method for producing solar cell module, and device for producing tab line with adhesive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To precisely align a tab line and to minimize an interval between adjacent solar cells to effectively secure a power generation area in a module as a whole.SOLUTION: Adhesive films 17, in each of which an adhesive layer 16 is layered on a base film, are conveyed while their adhesive layers 16 are directed to one surface on one end side of a tab line 15 and to the other surface on the other end side; the adhesive layers 16 are transferred to be stuck onto one surface on one end side and onto the other surface on the other end side of the tab line 15 when pressing members arranged on the base film sides of the adhesive films 17 press the adhesive films 17 to the tab line from the upper sides of the base films; and a stepped part 30 is formed in the tab line 15 when the pressing member 35 presses one end side of the tab line 15 from the other end side while the pressing member 36 presses the other end side of the tab line 15 from one end side.

Description

  The present invention relates to a method for producing a tab wire with an adhesive, a method for producing a solar cell module, and a device for producing a tab wire with an adhesive, and more particularly, to an improvement in a tab wire and a method for producing the same.

  For example, in a crystalline silicon-based solar battery module, a plurality of adjacent solar battery cells are connected by tab wires serving as interconnectors. One end side of the tab wire is connected to the front surface electrode of one solar battery cell, and the other end side is connected to the back surface electrode of the adjacent solar battery cell, thereby connecting the solar battery cells in series. At this time, one surface of the tab wire is bonded to the surface electrode of one solar cell, and the other surface of the other end is bonded to the back electrode of the adjacent solar cell.

  Specifically, in the solar battery cell, a bus bar electrode is formed on the light receiving surface and an Ag electrode is formed on the back surface connecting portion by screen printing of silver paste. In addition, Al electrodes and Ag electrodes are formed in regions other than the connection portion on the back surface of the solar battery cell.

  The tab wire is formed by providing a solder coat layer on both sides of the ribbon-like copper foil. For example, the tab wire is soldered to a rectangular copper wire having a width of 1 to 3 mm obtained by slitting a copper foil rolled to a thickness of about 0.05 to 0.2 mm or rolling a copper wire into a flat plate shape. It is formed by plating or dip soldering.

  The connection between the solar battery cell and the tab wire is performed by disposing the tab wire on each electrode of the solar battery cell and applying heat and pressure with a heating bonder to melt and cool the solder formed on the tab wire surface ( Patent Document 1).

  However, since soldering is performed at a high temperature of about 260 ° C., due to warpage and cracking of the solar cells, internal stress generated in the connection portion between the tab wire and the front surface electrode and the back surface electrode, further residual flux, etc. There is a concern that the connection reliability between the front and back electrodes of the solar battery cell and the tab wire is lowered.

  Therefore, conventionally, a conductive adhesive film that can be connected by thermocompression treatment at a relatively low temperature is used for connection between the front and back electrodes of the solar battery cell and the tab wire (Patent Document 2). As such a conductive adhesive film, a film obtained by dispersing spherical or scaly conductive particles having an average particle size on the order of several μm in a thermosetting binder resin composition is used.

  As shown in FIG. 12, the conductive adhesive film 50 is bonded on the front electrode and the back electrode, and then the tab wire 51 is superimposed and is heated and pressed from above the tab wire 51 by a heating bonder. Accordingly, as shown in FIG. 13, the conductive adhesive film 50 has a binder resin that exhibits fluidity and flows out from between the electrode and the tab wire 51, and the conductive particles 54 are between the electrode 53 and the tab wire 51. In this state, the binder resin is thermoset by being sandwiched and conducting between them. In this way, a string in which a plurality of solar cells 52 are connected in series by the tab wire 51 is formed.

  The plurality of solar cells 52 in which the tab wire 51 and the front and back electrodes are connected using the conductive adhesive film 50 are made of a surface protecting material having translucency such as glass and translucent plastic, PET ( It is sealed with a light-transmitting sealing material such as ethylene-vinyl acetate copolymer resin (EVA) between a back protective material made of a film such as Poly Ethylene Terephthalate.

JP 2004-356349 A Japanese Patent No. 4697194

  By the way, when the position shift generate | occur | produces in the process of bonding the electroconductive adhesive film 50 on the electrode 53 of a photovoltaic cell, or the process of arrange | positioning the tab wire 51 on the electroconductive adhesive film 50, a solar cell module is a tab wire. The adhesion area between the electrode 51 and the electrode 53 is reduced, and mechanical connection strength and electrical connection reliability are impaired.

  For this reason, it is necessary to adjust the sticking position of the electroconductive adhesive film 50 and the arrangement position of the tab wire 51, respectively, and the connection process of the electroconductive adhesive film 50 and the tab wire 51 becomes complicated. Further, when the width of the conductive adhesive film 50 is made wider than the width of the tab line 51 in consideration of the positional deviation between the tab wire 51 and the conductive adhesive film 50, it does not contribute to the conductive connection of the conductive adhesive film 50. The area increases and becomes uneconomical.

  Moreover, in the structure which concerns on patent document 2, the tab wire which connects photovoltaic cells is reversed between photovoltaic cells. In such a configuration, in order to secure a tab line inversion region, the distance between the tab line and the adjacent solar cells may be increased. If the interval between adjacent solar cells becomes longer, the area not contributing to power generation increases as a whole module, which is not preferable.

  The step of inverting the tab line is performed after joining the first solar cell and the tab line, and then joining the second solar cell. That is, it is necessary to provide a tab wire reversal process in addition to the joining process with the solar battery cells, and the manufacturing process becomes complicated.

  In addition, in the configuration according to Patent Document 2, there is a concern that the mechanical strength and durability may be lowered by twisting the tab wire, and the conduction resistance may be increased.

  The present invention has an adhesive that can accurately align the conductive adhesive film and the tab wire, minimize the interval between adjacent solar cells, and effectively secure the power generation area as a whole module. It aims at providing the manufacturing method of the manufacturing method of the manufacturing method of a tab wire, the manufacturing method of a solar cell module, and a tab wire with an adhesive agent.

  In order to solve the above-described problems, a method for manufacturing an adhesive-attached tab wire according to the present invention is a method for manufacturing a tab wire having an adhesive layer on the surface, on one side of one end of a tape-like tab wire. The adhesive layer of the first adhesive film having the adhesive layer laminated on the base film is conveyed toward the other side of the tab wire, and the adhesive layer is formed on the base film. The first adhesive film is transported toward the base film side of the first adhesive film by transporting the adhesive layer of the laminated second adhesive film toward the base film side, and the first adhesive film is transferred to the base by the first pressing member. The adhesive layer is transferred onto the tab line by pressing the tab line from above the film, and the second pressing member provided on the base film side of the second adhesive film causes the first 2 adhesive film The first pressing member that presses the one end side of the tab line from the other end side is caused to transfer the adhesive layer to the tab line by pressing the rum onto the tab line from the base film. The second pressing member that presses the other end side of the tab line is pressed from the one end side to form a step on the tab line, and the pressing by the first and second pressing members is performed. It is a thing to cancel.

  Further, in the method for manufacturing a solar cell module according to the present invention, a surface electrode of one solar cell and a back electrode of another solar cell adjacent to the one solar cell are tabbed via an adhesive. In the method for manufacturing solar cell modules connected by wires, the adhesive layer of the first adhesive film in which the adhesive layer is laminated on the base film is directed on one surface of one end of the tape-shaped tab wire. The second adhesive film having the adhesive layer laminated on the base film on the other surface of the other end side of the tab wire, and conveyed toward the adhesive layer of the second adhesive film. While pressing the first adhesive film from above the base film to the tab wire by the first pressing member provided on the base film side, the adhesive layer is transferred to the tab wire, and Up By pressing the second adhesive film onto the tab line from above the base film by the second pressing member provided on the base film side of the second adhesive film, the adhesive layer is moved to the tab line. The first pressing member that presses one end side of the tab wire is pushed in from the other end side, and the second pressing member that presses the other end side of the tab wire is the one end side. More pressing, forming a step on the tab wire, releasing the pressing by the first and second pressing members to form a tab wire with an adhesive, and the adhesive on the surface electrode of one solar cell One end side or the other end side of the attached tab wire is arranged via the adhesive layer, and the other end side of the adhesive-attached tab wire or the back electrode of another solar cell adjacent to the one solar cell. One end side is arranged through the adhesive layer It is intended.

  Moreover, the manufacturing apparatus of the adhesive-attached tab wire concerning this invention is equipped with the conveyance mechanism which conveys a tape-shaped tab wire, and the 1st adhesive film by which the adhesive bond layer was laminated | stacked on the base film. A first film transport mechanism for transporting onto one side of the side, and a second film for transporting the second adhesive film having an adhesive layer laminated on the base film to the other surface on the other end side of the tab wire A transport mechanism, a first pressing member provided on the base film side of the first adhesive film, and a first support member provided facing the first pressing member via the tab wire A first driving mechanism that moves the first pressing member and the first support member close to and away from each other, a second pressing member provided on the base film side of the second adhesive film, and the tab Opposing to the second pressing member via a wire And a second driving mechanism that moves the second pressing member and the second supporting member closer to and away from each other, and the first pressing member allows the first bonding to be performed. By pressing the film from above the base film to the tab wire, the adhesive layer is transferred to the tab wire, and the second pressing member is used to move the second adhesive film from above the base film. By pressing to the tab line, the adhesive layer is transferred to the tab line, and the first pressing member that presses one end side of the tab line is pushed in from the other end side, and the tab line The second pressing member that presses the other end side is pushed in from the one end side to form a step on the tab wire.

  According to the present invention, since the adhesive layer is provided, it is not necessary to adjust the alignment between the tab wire and the adhesive layer. In addition, since the present invention has a step formed in advance, internal stress due to bending is reduced, there is no possibility of peeling from the electrodes even if the space between the solar cells is narrowed, and connection reliability is improved. Can do.

It is a disassembled perspective view which shows a solar cell module. It is sectional drawing which shows the string of a photovoltaic cell. It is a top view which shows the back surface electrode and connection part of a photovoltaic cell. It is a side view which shows a tab wire with an adhesive agent. It is sectional drawing which shows an adhesive bond layer. It is a figure which shows the electroconductive adhesive film wound by the reel shape. It is a side view which shows the manufacturing apparatus of the tab wire with an adhesive agent, and is a figure which shows the process before transfer of an adhesive bond layer. It is a side view which shows the manufacturing apparatus of the tab wire with an adhesive agent, and is a figure which shows the formation process of transfer of an adhesive bond layer and a step. It is a side view which shows the manufacturing apparatus of the tab wire with an adhesive agent, and is a figure which shows the process after performing the transfer of an adhesive bond layer, and formation of a step. It is a perspective view which shows the photovoltaic cell which stuck the tab wire with an adhesive temporarily. It is a side view which shows the manufacturing apparatus of another tab wire with an adhesive agent. It is a perspective view which shows the conventional solar cell module. It is sectional drawing which shows the connection process of the tab wire in the conventional solar cell module.

  Hereinafter, the manufacturing method of the tab wire with an adhesive to which the present invention is applied, the manufacturing method of the solar cell module, and the manufacturing device of the tab wire with an adhesive will be described in detail with reference to the drawings. It should be noted that the present invention is not limited to the following embodiments, and various modifications can be made without departing from the scope of the present invention. Further, the drawings are schematic, and the ratio of each dimension may be different from the actual one. Specific dimensions should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[Solar cell module]
The solar cell module 1 to which this invention was applied has the string 4 by which the several photovoltaic cell 2 was connected in series by the tab wire 3 with the adhesive agent used as an interconnector, as shown in FIGS. 1-3. A matrix 5 in which a plurality of strings 4 are arranged is provided. And the solar cell module 1 is laminated together with the front cover 7 provided on the light receiving surface side and the back sheet 8 provided on the back surface side, with the matrix 5 sandwiched between the sealing adhesive sheets 6. A metal frame 9 such as aluminum is attached to the periphery as appropriate.

  As the sealing adhesive, for example, a translucent sealing material such as ethylene-vinyl acetate copolymer resin (EVA) is used. Moreover, as the surface cover 7, for example, a light-transmitting material such as glass or light-transmitting plastic is used. Further, as the back sheet 8, a laminated body in which glass or aluminum foil is sandwiched between resin films is used.

  Each solar battery cell 2 of the solar battery module 1 has a photoelectric conversion element 10. Hereinafter, a crystalline silicon solar cell using a single crystal silicon photoelectric conversion device or a polycrystalline silicon photoelectric conversion device will be described as an example of the photoelectric conversion device 10, but the present invention will be described later with reference to a solar cell. If it is a solar cell module which has the structure by which the surface electrode of 2 and the back surface electrode of the other adjacent photovoltaic cell 2 are connected by the tab wire 3, various various photoelectric conversion elements 10 can be used.

  The photoelectric conversion element 10 according to the crystalline silicon solar cell is provided with a finger electrode 12 for collecting electricity generated inside and a bus bar electrode 11 for collecting electricity of the finger electrode 12 on the light receiving surface side. The bus bar electrode 11 and the finger electrode 12 are formed, for example, by applying an Ag paste on the surface to be a light receiving surface of the solar battery cell 2 by screen printing or the like and then baking it. In addition, the finger electrode 12 is formed with a plurality of lines having a width of about 50 to 200 μm, for example, approximately in parallel at a predetermined interval, for example, every 2 mm, over the entire light receiving surface. The bus bar electrodes 11 are formed so as to be substantially orthogonal to the finger electrodes 12, and a plurality of bus bar electrodes 11 are formed according to the area of the solar battery cell 2.

  Further, the photoelectric conversion element 10 is provided with a back electrode 13 made of aluminum or silver on the back side opposite to the light receiving surface. As shown in FIGS. 2 and 3, the back electrode 13 is formed of an electrode made of, for example, aluminum or silver on the back surface of the solar battery cell 2 by screen printing, sputtering, or the like. The back electrode 13 has a tab line connection portion 14 to which a tab line 3 with an adhesive described later is connected.

  And the photovoltaic cell 2 is electrically connected to each bus bar electrode 11 formed on the surface and the back electrode 13 of the adjacent photovoltaic cell 2 by the adhesive layer 16 of the tab wire 3 with adhesive. Thus, the strings 4 connected in series are configured.

[Tab wire with adhesive]
As shown in FIG. 2, the adhesive-attached tab wire 3 is a long conductive substrate that electrically connects the adjacent solar cells 2X, 2Y, and 2Z. As shown in FIG. 4, the adhesive-attached tab wire 3 includes a metal tab 15 serving as an interconnector for connecting the bus bar electrode 11 and the back electrode 13 of the solar battery cell, one surface 15 b of one end side 15 a of the metal tab 15, And the adhesive layer 16 provided on the other surface 15d of the other end side 15c of the tab 15.

  The metal tab 15 has a width of 1 to 3 mm, for example, by slitting a copper foil or aluminum foil rolled to a thickness of 50 to 300 μm into a tape shape or rolling a thin metal wire such as copper or aluminum into a flat plate shape. Obtain a flat copper wire. The metal tab 15 is formed by applying gold plating, silver plating, tin plating, solder plating or the like to the flat copper wire.

[Adhesive layer]
As shown in FIG. 5, the adhesive layer 16 is a thermosetting binder resin layer in which spherical conductive particles 19 are contained in the binder resin 18 at a high density. As shown in FIG. 6, the adhesive layer 16 is first laminated on the base film 24 of the conductive adhesive film 17, and then in the manufacturing process of the adhesive-attached tab wire 3, one surface of the metal tab 15 is formed by thermocompression bonding. 15b and the other surface 15d are transferred.

  In addition, as for the adhesive bond layer 16, it is preferable that the minimum melt viscosity of the binder resin 18 is 100-100000 Pa.s from a pressable viewpoint. If the minimum melt viscosity of the adhesive layer 16 is too low, the resin will flow during the process of low pressure bonding to main curing, and connection failure or protrusion to the cell light receiving surface is likely to occur, causing a decrease in the light receiving rate. Moreover, even if the minimum melt viscosity is too high, defects are likely to occur when the adhesive-attached tab wire 3 is stuck, and the connection reliability may be adversely affected. The minimum melt viscosity can be measured while a sample is loaded in a predetermined amount of rotational viscometer and raised at a predetermined temperature increase rate.

[Conductive particles]
Examples of the conductive particles 19 contained in the binder resin 18 include metal particles such as nickel, gold, silver, and copper having an average particle diameter of about 10 μm, and Ni / Au plating as the outermost layer using resin particles as a core material. And the like.

  In addition, it is preferable that the adhesive layer 16 is 10-10000 kPa * s at the normal temperature vicinity, More preferably, it is 10-5000 kPa * s. When the adhesive layer 16 has a viscosity in the range of 10 to 10000 kPa · s, when the conductive adhesive film 17 is wound in a reel shape, blocking due to so-called protrusion can be prevented, and a predetermined tack can be obtained. You can maintain power.

[Binder resin]
The composition of the binder resin 18 of the adhesive layer 16 is not particularly limited as long as it does not impair the above-described characteristics, but more preferably a film-forming resin, a liquid epoxy resin, a latent curing agent, and a silane coupling. Containing the agent.

  The film-forming resin corresponds to a high molecular weight resin having an average molecular weight of 10,000 or more, and preferably has an average molecular weight of about 10,000 to 80,000 from the viewpoint of film formation. As the film-forming resin, various resins such as an epoxy resin, a modified epoxy resin, a urethane resin, and a phenoxy resin can be used. Among them, a phenoxy resin is preferably used from the viewpoint of the film formation state, connection reliability, and the like. .

  The liquid epoxy resin is not particularly limited as long as it has fluidity at room temperature, and all commercially available epoxy resins can be used. Specific examples of such epoxy resins include naphthalene type epoxy resins, biphenyl type epoxy resins, phenol novolac type epoxy resins, bisphenol type epoxy resins, stilbene type epoxy resins, triphenolmethane type epoxy resins, phenol aralkyl type epoxy resins. Resins, naphthol type epoxy resins, dicyclopentadiene type epoxy resins, triphenylmethane type epoxy resins, and the like can be used. These may be used alone or in combination of two or more. Moreover, you may use it combining suitably with other organic resins, such as an acrylic resin.

  As the latent curing agent, various curing agents such as a heat curing type and a UV curing type can be used. The latent curing agent does not normally react but is activated by some trigger and starts the reaction. The trigger includes heat, light, pressurization, etc., and can be selected and used depending on the application. Among these, in the present application, a thermosetting latent curing agent is suitably used, and the main curing is performed by heating and pressing the bus bar electrode 11 and the back electrode 13. When a liquid epoxy resin is used, a latent curing agent made of imidazoles, amines, sulfonium salts, onium salts, or the like can be used.

  As the silane coupling agent, epoxy, amino, mercapto sulfide, ureido, and the like can be used. Among these, in this Embodiment, an epoxy-type silane coupling agent is used preferably. Thereby, the adhesiveness in the interface of an organic material and an inorganic material can be improved.

  Moreover, it is preferable to contain an inorganic filler as another additive composition. By containing an inorganic filler, the fluidity of the resin layer during pressure bonding can be adjusted, and the particle capture rate can be improved. As the inorganic filler, silica, talc, titanium oxide, calcium carbonate, magnesium oxide and the like can be used, and the kind of the inorganic filler is not particularly limited.

  FIG. 6 is a diagram schematically illustrating an example of a product form of the conductive adhesive film 17. The conductive adhesive film 17 is formed in a tape shape by laminating an adhesive layer 16 on a base film 24. The tape-like conductive adhesive film 17 is wound and laminated on the reel 25 so that the base film 24 is on the outer peripheral side.

  There is no restriction | limiting in particular as the base film 24, PET (Poly Ethylene Terephthalate), OPP (Oriented Polypropylene), PMP (Poly-4-methyl-1-pentene), PTFE (Polytetrafluoroethylene) etc. can be used. The base film 24 is subjected to a peeling process on one surface to which the binder resin 18 is applied. For the release treatment, a known method can be used. For example, the base film 24 is surface-treated with a release treatment agent such as silicone-based, long-chain alkyl-based, fluorine-based, or molybdenum sulfide.

  The conductive adhesive film 17 may have a transparent cover film on the adhesive layer 16. In addition, the conductive adhesive film 17 is not limited to a reel shape, and may be a strip shape corresponding to the connection length of the bus bar electrode 11 of the solar battery cell 2 or the back electrode 13 to the tab wire connection portion 14.

  As shown in FIG. 6, when the conductive adhesive film 17 is provided as a reel product wound, the conductive adhesive film 17 has a viscosity of 10 to 10,000 kPa · s, so that the conductive adhesive film 17 Deformation can be prevented and a predetermined dimension can be maintained. Similarly, when two or more conductive adhesive films 17 are stacked in a strip shape, deformation can be prevented and a predetermined dimension can be maintained.

  The conductive adhesive film 17 dissolves conductive particles 19, a film forming resin, a liquid epoxy resin, a latent curing agent, and a silane coupling agent in a solvent. As the solvent, toluene, ethyl acetate or the like, or a mixed solvent thereof can be used. The resin-forming solution obtained by dissolution is applied onto the base film 24 and the solvent is volatilized to obtain the conductive adhesive film 17.

[Stepped]
As shown in FIGS. 2 and 4, the adhesive-attached tab wire 3 is stepped 30 at a position corresponding to the space between the solar battery cells 2 when connected to the bus bar electrode 11 and the back electrode 13 of the solar battery cell 2. Is formed. As shown in FIG. 4, by forming the stepped portion 30, the adhesive-attached tab wire 3 is such that one surface 15 b of the one end side 15 a where the adhesive layer 16 is formed is more than one surface 15 b of the other end side 15 c. 4 is similarly bent so that the other surface 15d of the other end 15c on which the adhesive layer 16 is formed is positioned higher in FIG. 4 than the other surface 15d of the one end 15a. ing.

  By using the tab wire with adhesive 3 in which the step 30 is formed in advance in a position corresponding to the space between the solar cells 2, the solar cell module 1 includes the bus bar electrode 11, the back electrode 13, the tab wire 3 with adhesive, The connection reliability can be improved.

  In other words, in order to secure a large light receiving area within a limited module area, the solar cell module 1 is desirably made as narrow as possible the area between the solar cells 2 that do not contribute to power generation. For that purpose, it is necessary to largely bend the tab wire arrange | positioned between the photovoltaic cells 2 between the front and back surfaces of the photovoltaic cells 2. However, as the area between the solar battery cells 2 is reduced, the bending of the tab line increases, and the internal stress against the bending also increases due to the rigidity of the tab line formed using the metal foil. By continuing to use in this state, the vicinity of the bent portion of the tab wire may be peeled off from the bus bar electrode 11 or the back electrode 13 due to internal stress.

  On the other hand, according to the solar cell module 1 using the tab wire 3 with an adhesive according to the present invention, the step 30 is formed in advance, so that the internal stress due to bending is reduced and the space between the solar cells 2 is narrowed. Even if it is made, there is no fear of peeling from the bus bar electrode 11 or the back electrode 13, and the connection reliability can be improved.

[Manufacturing equipment for tab wire with adhesive]
Next, a method for manufacturing the tab wire 3 with adhesive will be described. As shown in FIG. 7, the manufacturing apparatus 31 that manufactures the tab wire 3 with an adhesive includes a tab transport mechanism 32 that transports the tape-shaped metal tab 15 and a first film transport mechanism that transports the conductive adhesive film 17. 33 and the 2nd film conveyance mechanism 34, the 1st press member 35 and the 2nd press member 36 which transfer the adhesive bond layer 16 of the electroconductive adhesive film 17 to the metal tab 15, and the 1st press member 35 The first support member 37 and the second support member 38 provided to face the second pressing member 36 and the first pressing member 35 and the first supporting member 37 are moved closer to and away from each other. A drive mechanism 39 and a second drive mechanism 40 that moves the second pressing member 36 and the second support member 38 close to and away from each other are provided.

  The tab transport mechanism 32 pulls out the metal tab 15 from the tab wound body 42 in which the metal tab 15 molded in a tape shape is wound in a roll shape, and the first and second pressing members 35 and 36 and the first, It is conveyed between each of the second support members 37 and 38.

  The first film transport mechanism 33 is provided on the one surface 15 b of the metal tab 15, and the conductive adhesive film 17 drawn from the reel 25 is placed with the adhesive layer 16 facing the one surface 15 b side of the metal tab 15. It conveys on one surface 15b of one end side 15a of the tab 15. The first film transport mechanism 33 includes a plurality of guide rollers 43 that guide the transport of the conductive adhesive film 17, a recovery reel 44 that recovers the base film 24 after the adhesive layer 16 is peeled off, and the conductive adhesive film And a half-cut mechanism 45 that cuts only the 17 adhesive layers 16 in accordance with the length of transfer to the metal tab 15.

  The second film transport mechanism 34 is provided below the other surface 15 d of the metal tab 15, and the conductive adhesive film 17 drawn out from the reel 25 faces the adhesive layer 16 toward the other surface 15 d of the metal tab 15. The other end 15c of the metal tab 15 is conveyed on the other surface 15d. Similarly to the first film transport mechanism 33, the second film transport mechanism 34 includes a guide roller 43, a collection reel 44, and a half cut mechanism 45.

  The first pressing member 35 is for transferring the adhesive layer 16 of the conductive adhesive film 17 to the one surface 15b of the metal tab 15, and is provided above the one end side 15a of the conductive adhesive film 17 so as to be movable up and down. . As the first pressing member 35, for example, a heating pressing head is used. The heating and pressing head incorporates a heater, is heated to a predetermined temperature by a first drive mechanism 39 described later, and heats the conductive adhesive film 17 together with the first support member 37 onto the one surface 15 b of the metal tab 15. Press. Note that the heating and pressing head may appropriately interpose a cushioning material such as silicon rubber between the heat pressing surface that presses the conductive adhesive film 17 and the base film 24.

  The second pressing member 36 transfers the adhesive layer 16 of the conductive adhesive film 17 to the other surface 15d of the metal tab 15, and can be moved up and down below the other end side 15c of the conductive adhesive film 17. Provided. As with the first pressing member 35, for example, a heating and pressing head is used as the second pressing member 36, and the second pressing member 36 is driven by the second driving mechanism 40.

  The first support member 37 is disposed opposite to the first pressing member 35 via the conductive adhesive film 17 and the metal tab 15, and sandwiches the conductive adhesive film 17 and the metal tab 15 together with the first pressing member 35. . The first support member 37 is provided below the one end side 15a of the metal tab 15 and is provided so as to be fixed or liftable. Further, the first support member 37 may be provided with a suction unit that sucks the metal tab 15 to which the adhesive layer 16 is transferred by vacuuming or the like. By adsorbing the metal tab 15 by the adsorbing means, the adhesive layer 16 can be reliably peeled from the base film 24 when the pressing of the first pressing member 35 is released.

  The second support member 38 is disposed opposite to the second pressing member 36 via the conductive adhesive film 17 and the metal tab 15, and sandwiches the conductive adhesive film 17 and the metal tab 15 together with the second pressing member 36. . The second support member 38 is provided above the other end side 15c of the metal tab 15, and is provided so as to be fixed or liftable. The second support member 38 may also be provided with a suction means for sucking the metal tab 15 in the same manner as the first support member 37.

  As shown in FIG. 8, the first drive mechanism 39 brings the first pressing member 35 close to the first support member 37 to sandwich the conductive adhesive film 17 and the metal tab 15, and the conductive adhesive film Seventeen adhesive layers 16 are transferred from the base film 24 to the one surface 15 b of the metal tab 15. In addition, the second driving mechanism 40 causes the conductive adhesive film 17 and the metal tab 15 to be sandwiched by bringing the second pressing member 36 close to the second support member 38, and the adhesive layer of the conductive adhesive film 17. 16 is transferred from the base film 24 to the other surface 15 d of the metal tab 15.

  The first and second drive mechanisms 39 and 40 drive the first and second pressing members 35 and 36 to form the step 30 on the metal tab 15. Specifically, in the first and second drive mechanisms 39 and 40, the first pressing member 35 that presses the one end side 15a of the metal tab 15 pushes in from the other end side 15c, and the other end side of the metal tab 15 The second pressing member 36 that presses 15c is driven so as to be pushed in from the one end side 15a. As a result, the metal tab 15 has one surface 15b on one end side 15a to which the adhesive layer 16 is transferred, positioned below the one surface 15b on the other end side 15c in FIG. A stepped portion 30 is formed by bending so that the other surface 15d of the other end 15c is positioned higher than the other surface 15d of the one end 15a in FIG.

  The first pressing member 35 and the second pressing member 36 are relatively pushed in, and the first pressing member 35 pushes the one end 15a of the one surface 15b of the metal tab 15 more than the other end 15c. Accordingly, the other surface 15d of the metal tab 15 is naturally pushed into the other end 15c more than the one end 15a. Therefore, for example, as shown in FIG. 8, the second pressing member 36 and the second supporting member 38 sandwich the metal tab 15 at the position where the second pressing member 36 and the second supporting member 38 are conveyed from the tab wound body 42, and only the first pressing member 35 is interposed. The step 30 can be formed by pressing the metal tab 15 against the first support member 37 fixedly disposed below the metal tab 15.

  Further, as shown in FIG. 8, the manufacturing apparatus 31 is provided with a cutting mechanism 41 for cutting the adhesive-attached tab wire 3 on which the adhesive layer 16 is transferred and the step 30 is formed to a predetermined length. It has been.

[Manufacturing process of tab wire with adhesive]
Next, the manufacturing process of the adhesive-attached tab wire 3 using the manufacturing apparatus 31 will be described. First, as shown in FIG. 7, the metal tab 15 wound around the tab wound body 42 is pulled out by the tab transport mechanism 32, and each reel is transported by the first and second film transport mechanisms 33 and 34. The conductive adhesive film 17 wound around 25 is pulled out. At this time, the first and second drive mechanisms 39 and 40 separate the first pressing member 35 and the first support member 37, and separate the second pressing member 36 and the second support member 38. ing. In addition, the first and second film transport mechanisms 33 and 34 are configured so that only the adhesive layer 16 of the conductive adhesive film 17 is connected to the bus bar electrode 11 and the back electrode 13 by each half-cut mechanism 45. The length is cut. Thereby, the metal tab 15 is opposed to the one surface 15b of the one end side 15a and the adhesive layer 16 half-cut to a predetermined length, and is half-cut to the other surface 15d of the other end side 15c and the predetermined length. The adhesive layer 16 is opposed.

  Next, as shown in FIG. 8, the first driving mechanism 39 heats the first pressing member 35 to a predetermined temperature at which the binder resin 18 of the adhesive layer 16 exhibits fluidity but does not start thermosetting. The first pressing member 35 is brought close to the first support member 37 and heat-presses the conductive adhesive film 17 from the base film 24 to the one surface 15b of the metal tab 15. Similarly, the second driving mechanism 40 heats the second pressing member 36 to a predetermined temperature at which the binder resin 18 of the adhesive layer 16 exhibits fluidity but does not start thermosetting, and the second pressing member 36 36 is brought close to the second support member 37, and heat-presses the conductive adhesive film 17 from the base film 24 to the other surface 15 d of the metal tab 15. As a result, the adhesive layer 16 is transferred from the base film 24 onto the one surface 15b of the one end side 15a of the metal tab 15 and onto the other surface 15d of the other end side 15c.

  Further, in the first and second drive mechanisms 39, 40, the first pressing member 35 pushes the one end side 15 a of the metal tab 15 into the other end side 15 c and the second pressing member 35 serves as the metal tab 15. The other end side 15c is driven to be pushed in from the one end side 15a. As a result, the metal tab 15 is bent between the one end side 15 a pressed by the first pressing member 35 and the other end side 15 b pressed by the second pressing member 36, thereby forming a step 30. The Further, the cutting mechanism 41 cuts the metal tab 15 at a predetermined position.

  In this state, the first and second drive mechanisms 39, 40 hold the metal tab 15 and the conductive adhesive film 17 at a predetermined pressure for a predetermined time, and then, as shown in FIG. 35 and the first support member 37 are separated from each other, and the second pressing member 36 and the second support member 38 are separated from each other. Thereby, the adhesive layer 16 peels from the base film 24 and the conductive adhesive film 17 is transferred to the metal tab 15.

  At this time, the manufacturing apparatus 31 provides the first and second support members 37 and 38 with the suction means for the metal tab 15 to raise the first pressing member 35 from the state shown in FIG. By lowering the member 36 and separating from the first and second support members 37 and 38, the metal tab 15 and the adhesive layer 16 do not follow the base film 24. Can be peeled off from the base film 24.

  Thus, the manufactured tab wire 3 with an adhesive is such that one surface 15b of one end side 15a to which the adhesive layer 16 of the metal tab 15 is transferred is lower in FIG. 4 than one surface 15b of the other end side 15c. In the same manner, the other surface 15d of the other end 15c to which the adhesive layer 16 has been transferred is bent so that the other surface 15d of the other end 15a is located above the other surface 15d of the one end 15a in FIG. Is formed.

  The tab wire 3 with the adhesive is temporarily attached on the tab wire connecting portion 14 of the back electrode 13 of the solar battery cell 2 via the adhesive layer 16 on one surface 15b of the one end side 15a, and the other surface 15d of the other end side 15c. Is temporarily pasted on the bus bar electrode 11 of the adjacent solar battery cell 2 through the adhesive layer 16. At this time, as shown in FIG. 10, the tabbed 3 with adhesive is easily bent according to the step 30 in the region between the solar cells 2 because the step 30 is formed in advance. Accordingly, even if the region between the solar cells 2 is narrowed, the adhesive-attached tab wire 3 suppresses internal stress accompanying the bending of the metal tab 15 and prevents peeling from the bus bar electrode 11 and the back electrode 13. .

  In this way, the strings 4 to which the plurality of solar cells 2 are connected are formed by the tab wires 3 with the adhesive, and the matrix 5 in which a plurality of the strings 4 are arranged is formed. The matrix 5 is sandwiched between sealing adhesive sheets 6 and laminated together with a front cover 7 provided on the light receiving surface side and a back sheet 8 provided on the back surface side.

  In this laminating process, the adhesive-attached tab wire 3 is heated for a predetermined time (for example, about 15 seconds) at a predetermined temperature (for example, about 180 ° C.) and a predetermined pressure (for example, about 2 MPa) at which the adhesive layer 16 is thermally cured. Pressurized. Thus, the adhesive layer 16 causes the binder resin 18 to flow out from between the metal tab 15 and the bus bar electrode 11 or the back electrode 13, and the conductive particles 19 are formed between the metal tab 15, the bus bar electrode 11 or the back electrode 13. It is sandwiched between and cured in this state. In this way, the metal tab 15, the bus bar electrode 11, and the back electrode 13 are electrically and mechanically connected via the adhesive layer 16. Thereafter, the solar cell module 1 is formed by appropriately attaching a metal frame 9 such as aluminum around the periphery.

  In addition, the solar cell module 1 heats and presses the adhesive-attached tab wire 3 in the laminating step with the sealing adhesive sheet 6, and the present invention also provides the adhesive-attached tab wire 3 between the solar cells 2. After the temporary sticking over the metal tab 15, the metal tab 15 may be connected to the electrodes 11 and 13 by heat and pressure with a heating and pressing head (not shown).

  Moreover, you may use the photovoltaic cell 2 of the so-called bus bar-less structure in which the bus-bar electrode 11 is not formed as the photovoltaic cell 2. FIG. In this case, the other end side 15 c of the adhesive-attached tab wire 3 is connected such that the adhesive layer 16 intersects the plurality of finger electrodes 12.

  Furthermore, in the above description, the adhesive layer 16 that connects the metal tab 15 and the electrodes 11 and 13 is one in which the conductive particles 19 are contained in the binder resin 18. However, in the present invention, the adhesive layer 16 is used. Alternatively, an insulating adhesive layer in which the conductive resin 19 is not contained in the binder resin 18 can be used.

[Other pressing members]
In addition, the manufacturing apparatus 31 of the tab wire 3 with an adhesive uses a heating and pressing head as the first and second pressing members 35 and 36, and as shown in FIG. 11, the base film of the conductive adhesive film 17 is used. A pressure roller 46 that rolls on the surface 24 may be used. The pressure roller 46 rolls on the base film 24 by rolling on the base film 24 in a state where the metal tab 15 and the conductive adhesive film 17 are supported by the first and second support members 37 and 38. The laminated adhesive layer 16 can be transferred to the metal tab 15 side, and a step 30 can be formed between the one end side 15a and the other end side 15c of the metal tab 15.

  Next, examples of the present invention will be described. In the present embodiment, the conductive adhesive film 17 is disposed on the one surface 15b of the one end side 15a of the metal tab 15 and the other surface 15d of the other end side 15c in accordance with the above-described manufacturing method of the present invention. The attachment and the step 30 are formed, and the adhesive-attached tab wire 3 is obtained by cutting into a predetermined length (step 1). Then, the tab wire 3 with an adhesive was temporarily attached on the bus bar electrode 11 of the solar battery cell 2 and on the back electrode 13 of the adjacent solar battery cell 2 (step 2). Next, the adhesive-attached tab wire 3 was hot-pressed with a heating and pressing head and connected (step 3).

  In the comparative example, according to a conventional construction method, a conductive adhesive film was temporarily pasted on the bus bar electrode and the back electrode of the solar battery cell, and the base film was peeled off (step 1). Subsequently, the tab wire was cut into a predetermined length and conveyed to the solar battery cell (step 2). Thereafter, tab wires were disposed on the adhesive layer temporarily attached on the bus bar electrode and the back electrode of the solar battery cell (step 3). At this time, the tab line was arranged in a misaligned state so that the overlap with the adhesive layer was insufficient. Next, heat and pressure were applied from above the tab line by a heating and pressing head (step 4).

The adhesive layer of the conductive adhesive film used in Examples and Comparative Examples has the following composition.
Phenoxy resin ... 22 parts by weight Bisphenol type epoxy resin ... 15 parts by weight acrylic rubber ... 15 parts by weight latent curing agent ... 45 parts by weight silane coupling agent ... 2 parts by weight Ni particles -15 weight part Moreover, the film width of the electroconductive adhesive film was 0.5 mm.

  The width of the tab line was 1.5 mm. Two 6-inch single crystal silicon cells were used as solar cells. The thermal pressure conditions for the tab wire are 180 ° C., 15 seconds, and 2 MPa.

About the solar cell string concerning an Example and a comparative example, power generation efficiency was measured after the connection initial stage of a tab line, and a thermal shock test (-40 degreeC, 3 hours <-> 100 degreeC, 3 hours, 1000 cycles). The power generation efficiency was measured using a solar simulator (manufactured by Nisshinbo Mechatronics, PVS1116i) under the conditions of illuminance of 1000 W / m ² , temperature of 25 ° C., and spectrum AM of 1.5 G. And the conversion efficiency after a thermal shock test made 95% or more of the initial value (circle), and less than 95% made x.

  As shown in Table 1, according to the solar cell string according to the example, since the tab wire with the adhesive is used, the alignment between the adhesive layer and the metal tab is taken from the beginning. Therefore, the power generation efficiency after the thermal shock test was as good as 95% in the initial stage of connection. On the other hand, in the comparative example, since the adhesive layer and the tab wire are out of alignment, the power generation efficiency after the thermal shock test was less than 95%.

  Further, in the embodiment, since the tab line with the adhesive is used, the alignment between the adhesive layer and the metal tab is taken from the beginning, so there is no need for alignment adjustment. On the other hand, in a comparative example, since an electroconductive adhesive film and a tab wire are arrange | positioned separately, it is necessary to adjust alignment.

  Furthermore, in an Example, it manufactures in three processes of manufacture of the tab wire with an adhesive agent, temporary sticking of the tab wire with an adhesive agent, and the main crimping | compression-bonding of the tab wire with an adhesive agent. On the other hand, in the comparative example, it can be seen that four steps of temporary attachment of the conductive adhesive film, cutting and conveyance of the tab line, arrangement of the tab line (alignment adjustment), and final pressing of the tab line are required, and the number of steps is increased.

DESCRIPTION OF SYMBOLS 1 Solar cell module, 2 photovoltaic cell, 3 tab line with adhesive, 4 strings, 5 matrix, 6 sheet, 7 surface cover, 8 back sheet, 9 metal frame, 10 photoelectric conversion element, 11 bus bar electrode, 12 finger electrode , 13 Back electrode, 14 Tab wire connection part, 15 Metal tab, 16 Adhesive layer, 17 Conductive adhesive film, 18 Binder resin, 19 Conductive particle, 24 Base film, 25 reel, 30 Step, 31 Production device, 32 Tab transport mechanism, 33, 34 Film transport mechanism, 35, 36 Press member, 37, 38 Support member, 39, 40 Drive mechanism, 42 Tab winding body, 43 Guide roller, 44 Collection reel, 45 Half cut mechanism, 46 Pressure roller

Claims (8)

In the manufacturing method of the tab wire provided with an adhesive layer on the surface,
On one side of one end of the tape-like tab wire, the adhesive layer of the first adhesive film laminated on the base film is conveyed toward the adhesive layer,
On the other surface of the other end side of the tab wire, the adhesive layer of the second adhesive film laminated on the base film is directed and conveyed.
By pressing the first adhesive film against the tab line from the base film by the first pressing member provided on the base film side of the first adhesive film, the adhesive layer is moved to the tab. While being transferred to the wire, by pressing the second adhesive film on the base film from above the base film by the second pressing member provided on the base film side of the second adhesive film, Transfer the adhesive layer to the tab wire,
The first pressing member that presses one end side of the tab wire is pressed in from the other end side, and the second pressing member that presses the other end side of the tab wire is pressed in from the one end side, Form a step on the tab wire,
The manufacturing method of the tab line with an adhesive which cancels | releases the press by the said 1st, 2nd press member. The tab wire connects the surface electrode of one solar battery cell and the back electrode of another solar battery cell adjacent to the one solar battery cell,
The said step is a manufacturing method of the tab wire with an adhesive of Claim 1 formed in the position according to between said one photovoltaic cell and said other photovoltaic cell.   The adhesive according to claim 1 or 2, wherein the first and second pressing members are a pair of pressing heads that sandwich the tab wire and the adhesive film, or a pressure roller that rolls on the base film. Manufacturing method of tabbed line.   The adhesive film is a conductive adhesive film in which conductive particles are contained in the adhesive layer, or an insulating adhesive film in which conductive particles are not contained in the adhesive layer. The manufacturing method of the tab wire with an adhesive as described in 2. In the method of manufacturing a solar cell module in which the surface electrode of one solar cell and the back electrode of another solar cell adjacent to the one solar cell are connected by a tab wire via an adhesive,
On one side of one end of the tape-like tab wire, the adhesive layer of the first adhesive film laminated on the base film is conveyed toward the adhesive layer,
On the other surface of the other end side of the tab wire, the adhesive layer of the second adhesive film laminated on the base film is directed and conveyed.
By pressing the first adhesive film against the tab line from the base film by the first pressing member provided on the base film side of the first adhesive film, the adhesive layer is moved to the tab. While being transferred to the wire, by pressing the second adhesive film on the base film from above the base film by the second pressing member provided on the base film side of the second adhesive film, Transfer the adhesive layer to the tab wire,
The first pressing member that presses one end side of the tab wire is pressed in from the other end side, and the second pressing member that presses the other end side of the tab wire is pressed in from the one end side, Form a step on the tab wire,
Release the pressing by the first and second pressing members to form a tab line with an adhesive,
One end side or the other end side of the adhesive-attached tab wire is arranged on the surface electrode of one solar battery cell via the adhesive layer, and the back electrode of another solar battery cell adjacent to the one solar battery cell The manufacturing method of the solar cell module which arrange | positions the other end side or one end side of the said tab line with an adhesive agent via the said adhesive bond layer.   6. The method of manufacturing a solar cell module according to claim 5, wherein the step is located between the one solar cell and the other solar cell. A transport mechanism for transporting tape-like tab wires;
A first film transport mechanism for transporting a first adhesive film having an adhesive layer laminated on a base film onto one surface of one end of the tab wire;
A second film transport mechanism for transporting a second adhesive film having an adhesive layer laminated on the base film onto the other surface on the other end side of the tab wire;
A first pressing member provided on the base film side of the first adhesive film, a first support member provided facing the first pressing member via the tab wire, and the first A first driving mechanism that moves the pressing member and the first supporting member close to and away from each other;
A second pressing member provided on the base film side of the second adhesive film, a second support member provided facing the second pressing member via the tab wire, and the second 2 pressing members and a second drive mechanism for moving the second support member closer to and away from each other,
By pressing the first adhesive film onto the tab wire from above the base film by the first pressing member, the adhesive layer is transferred to the tab wire, and by the second pressing member. , By pressing the second adhesive film from above the base film to the tab line, the adhesive layer is transferred to the tab line,
The first pressing member that presses one end side of the tab wire is pressed in from the other end side, and the second pressing member that presses the other end side of the tab wire is pressed in from the one end side, An apparatus for manufacturing a tab wire with an adhesive that forms a step on the tab wire.   The first and second support members are provided with suction means for sucking the tab wires, and the tab wires are sucked by the suction means when the pressing of the first and second pressing members is released. The manufacturing apparatus of the adhesive-attached tab wire of Claim 7.

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