JP4765447B2 - Thin film solar cell module manufacturing method and manufacturing apparatus - Google Patents

Description

  The present invention relates to a thin-film solar cell module manufacturing method and a manufacturing apparatus for manufacturing a thin-film solar cell module using a flexible type insulating substrate by a roll-to-roll method.

  In recent years, research and development on so-called clean energy has been promoted from the standpoint of environmental protection. Among them, solar cells have virtually unlimited use of sunlight, which is their resource, and are more pollution-free than other conventional power generations because they directly convert solar energy into electrical energy. It has attracted a great deal of attention.

  As a typical example of a solar cell (photoelectric conversion device) in which a plurality of photoelectric conversion elements formed on the same substrate are connected in series, a thin film solar cell can be given (for example, see Patent Document 1). Thin-film solar cells are industrially and technically required for practical solar cells such as being thin and lightweight, having excellent mass productivity, being inexpensive to manufacture, and being easy to increase in area. Since it has an advantage, it is considered that it will become the mainstream of future solar cells. The main use of thin-film solar cells is of course for power supply, but in addition to that, the demand has expanded to use for business use and general residential use attached to the roof or windows of buildings. ing. Conventional thin-film solar cells generally use an insulating substrate such as a glass substrate. However, there is a strong demand for reduction in thickness and weight due to the disadvantage of being thick and heavy and easily cracked and for improving workability for installation on an outdoor roof or the like. In response to these demands, in recent years, research and development of flexible type solar cells such as plastic films have been promoted and put into practical use from the viewpoints of weight reduction, workability, and mass productivity. Furthermore, research and development and practical application of thin-film solar cells using an insulating film substrate with an insulating coating on a flexible metal material are also in progress. Mass production is possible by the continuous forming method using the roll-to-roll method or stepping roll method taking advantage of this flexibility. When a thin film solar cell is formed on a flexible type insulating substrate such as a plastic film, an electrode is also arranged on the opposite side (back side) of the solar cell of the substrate and connected through the substrate. Thus, the ratio of the solar cell area to the substrate area can be increased, and characteristics such as high utilization efficiency of sunlight can be provided.

  2A and 2B are schematic views showing an example of the above-described thin film solar cell (hereinafter referred to as “thin film solar cell submodule”). 2A is a plan view, and FIG. 2B is a sectional view taken along line XX in FIG. 2A. As shown in FIGS. 2A and 2B, the first electrode is sequentially formed from one side of the insulating substrate S on one surface of the flexible type insulating substrate S (which is a sunlight incident surface, which is referred to as a surface). The layer E1, the photoelectric conversion layer P, and the second electrode E2 that is a transparent electrode are stacked, and are divided and separated into a plurality of unit solar cells (unit cells Un) by a patterning line L1 by laser processing. A third electrode layer E3 and a fourth electrode layer E4 (both are collectively referred to as a back electrode Er) are laminated in this order on the opposite surface (back surface) of the insulating substrate S, and this is also a patterning line by laser processing. It is divided and separated by L2, and is formed with back surface electrodes En, n + 1, etc. corresponding to the unit solar cells Un, Un + 1, etc. The insulating substrate S has a connection hole H1 and a current collection hole H2 penetrating therethrough, the first electrode layer E1 and the back electrode Er pass through the connection hole H1, and the second electrode layer E2 and the back electrode Er are current collection holes. It is electrically connected (conductive) through H2. The two types of holes H1 and H2 are a back electrode (fourth electrode layer E4), a current collecting hole H2, a second electrode layer E2, a photoelectric conversion layer P, a first electrode layer E1, a connection hole H1, and a back electrode (third. It is used for series connection of unit solar cells in the order of electrode layer E3). Therefore, the back electrode En-1, n and the back electrode En, n + 1 adjacent to any unit cell Un etc. are connected in series as the back electrode En-1, n-unit cell Un-back electrode En, n + 1. The solar cells are connected in series in multiple stages. A necessary voltage can be output by repeating the series connection of the adjacent unit solar cells separated as described above. For example, in order to obtain an alternating current of 100 V as a commercial power source by alternating current with an inverter, 100 V or higher is desired <actually, several tens or more unit solar cell elements are connected in series. The insulating substrate S is a polyimide-based film and has a thickness of 50 μm. As the insulating substrate S, polyethylene naphthalate (PEN), polyether sulfone (PES), polyethylene terephthalate (PET), or an aramid film can be used. .

  3A, 3B, and 3C are cross-sectional views of the current collecting hole H2 portion of the solar cell module using the above-described thin film solar cell submodule, and FIG. 3A is the current collecting hole H2. FIG. 3B is a cross-sectional view of the state where the protective resin F is coated on the protective resin F, and FIG. 3B shows a state where the adhesive resin sealing material J1 and the surface protective film J3 are stacked in this order on the protective resin F (light receiving surface side). FIG. 3C is a cross-sectional view of the state where the adhesive resin sealing material J2 and the back reinforcing plate B are stacked on the side, and FIG. In the state of FIG. 3 (A), the protective resin F covers the inner wall of the current collecting hole H2, the insulating substrate S surface at the periphery thereof, and the laser patterning line L1 (not shown). In the state of FIG. 3 (B), a solar cell module is formed by heat treatment in which pressure is applied and the adhesive resin sealing materials J1 and J2 are sufficiently bonded and cured. During the heat treatment, the viscosity of the adhesive resin sealing materials J1 and J2 decreases, and the protective resin F enters the current collecting hole H2, and the protective resin F is mixed with each other in the vicinity of the boundary between the adhesive resin sealing materials J1 and J2. Fit. Since the above heat treatment etc. are the same also in the connection hole H1, the description is omitted.

  The materials used for the above-described solar cell module are as follows. As the surface protective film located on the outermost surface on the light receiving surface side, a material having high moisture resistance, weather resistance, and transparency is suitable, and for example, ethylene tetrafluoroethylene (ETFE) is used. As the adhesive resin sealing material J1, etc., for example, ethylene-vinyl acetate polymer (Ethylene Vinyl Acetate: EVA) is used from the viewpoint of adhesive strength. As the material of the protective resin F, for example, a solvent-soluble fluororesin paint is used from the viewpoint of preventing corrosion of the thin-film solar cell element due to acetic acid and moisture generated by hydrolysis of the adhesive resin sealing material J1 or the like. . A stainless steel plate, a coated steel plate or the like is used as the back reinforcing plate B disposed on the back side which is a non-light receiving surface.

  The thin film solar cell submodule and the thin film solar cell module using the flexible insulating substrate S as described above are excellent in mass productivity and workability, and have a feature that the cost of the module and the work can be reduced. As a method for manufacturing such a thin-film solar cell module, a roll-to-roll is used in which module constituent materials are supplied in the form of a roll film, wiring connection, resin sealing, adhesion of a protective material, etc. The manufacturing method of a system or a stepping roll system is proposed.

  FIG. 4 shows a conventional thin film that implements a roll-to-roll manufacturing method used in the process of forming the protective resin layer F on the light-receiving surface of the thin-film solar cell submodule, which is one step of the above-described solar cell module manufacturing method. 1 is a schematic diagram of a solar cell module manufacturing apparatus 10. FIG. As shown in FIG. 4, the main structure of the conventional thin film solar cell module manufacturing apparatus 10 is that the unwinding shaft R1 for unwinding the thin film solar cell module 1 manufactured in a roll shape, a solvent-soluble fluororesin The coating F (protective resin layer F), the gravure roll G for applying (transferring) the solvent-soluble fluororesin coating F to the light receiving surface of the thin-film solar cell sub-module 1 by the applicator roll, and the thin-film solar cell sub-module 1 In order to wind up the drying furnace HB for heating and drying the solvent-soluble fluororesin paint F applied to the light-receiving surface and the solar cell submodule 1f applied with the solvent-soluble fluororesin paint F to the light-receiving surface in a roll shape. Winding shaft R2.

  As shown in FIG. 4, the thin-film solar cell submodule 1 attached to the unwinding shaft R1 is coated with a solvent-soluble fluororesin paint F on the light receiving surface by the gravure roll G to become a solar cell submodule 1f. It is led to the drying furnace HB through the guide rolls GR1 and GR2. After the soluble fluororesin paint F is heated and dried in the drying furnace HB, the solar cell submodule 1f is a movable roll for controlling the guide roll GR3, the amount of accumulation of the solar cell submodule 1f being conveyed, and the like. The dancer roll DR, the guide roll GR4, the drive roll FD, and the press roll P are conveyed to the winding shaft R2. While the gravure roll G is rotated in a state where it is pressed against the light receiving surface of the thin film solar cell submodule 1 at a constant pressure in synchronization with the above conveyance, the solvent-soluble fluororesin paint F is applied to the thin film solar cell submodule. 1 is applied to the light receiving surface. The thin film solar cell submodule 1f is sent to a drying furnace HB maintained at 180 ° C., and the protective resin layer F is formed by heat drying. The thin-film solar cell submodule 1f is again wound into a roll shape on the winding shaft R2.

Japanese Patent No. 2755281

  The conventional thin-film solar cell module manufacturing apparatus 10 described above has the following problems.

(1) Solvent-soluble fluororesin paint F is applied and is transported while the thin-film solar cell submodule 1f after being heated and dried in the drying furnace HB is wound around the winding shaft R2 in a roll shape. As a result of the sticking of the type fluororesin F to the guide roll GR3 or the like, defects such as wrinkles or breakage occurred in the thin film solar cell submodule 1f, and the yield was markedly reduced.

(2) In addition to the above problem (1), when the thin film solar cell submodule 1f is wound around the winding shaft R2 in a roll shape, similar defects such as wrinkles or folds are generated, and the yield is significantly reduced. It was.

(3) Furthermore, in the laminating process by the roll-to-roll method for forming the module adhesive layer by the adhesive resin sealing material J1 etc., which is a subsequent process of the solvent-soluble fluororesin paint F coating step, When the thin film solar cell submodule 1f wound on the winding shaft R2 is unwound from the roll (winding shaft R2), the thin film solar cell submodule 1f is attached to the surface facing the solvent-soluble fluororesin F. A defect that the thin film layer on the light receiving surface of the battery submodule 1f or the thin film layer on the opposite surface peeled off from the insulating substrate S occurred, and the yield was significantly reduced.

(4) In addition to the problem of (3) above, a roll-to-roll method for forming a module adhesive layer with an adhesive resin sealing material J1, etc., which is a subsequent process of the solvent-soluble fluororesin coating F coating step In the laminating process, the thin film solar cell submodule 1f unwound from the roll (winding shaft R2) can be attached to the guide roll (GR) in the same manner as the solvent-soluble fluororesin coating F coating step. As a result, defects such as wrinkles or creases occurred, significantly reducing yield.

  In general, the problem of conveyance failure due to sticking as described above is dealt with by inserting an interleaving paper on the surface coated with the resin material or coating the surface of the guide roll with a release material such as fluororesin. It is said that it is good. However, the insertion of the interleaf paper leads to an increase in the transportation equipment and the material cost, and the coating on the surface of the guide roll is expensive. Thus, there is a problem that it is difficult to reduce the production cost with the above countermeasures. there were.

  Accordingly, an object of the present invention is to solve the above-mentioned problem, and it is possible to reduce the production cost by reducing the yield due to poor conveyance due to sticking in the protective resin coating treatment of the light receiving surface of the thin film solar cell submodule. An object of the present invention is to provide a thin-film solar cell module manufacturing apparatus and a manufacturing method excellent in productivity that can be prevented without increasing.

The thin film solar cell module manufacturing method of the present invention is a thin film solar cell module manufacturing method for manufacturing a thin film solar cell module using a flexible type insulating substrate by a roll-to-roll method, and unwinds from an unwinding shaft. A protective resin layer forming step of forming a protective resin layer on the light-receiving surface of the thin film solar cell module using a solvent-soluble fluororesin, and winding onto the protective resin layer formed by the protective resin layer forming step A module adhesive layer forming step of forming a module adhesive layer using an adhesive resin sealing material continuously before winding on the shaft, and the protective resin layer forming step is a solvent on the light receiving surface of the thin film solar cell module The soluble fluororesin is dried by heating in a drying furnace, and the module adhesive layer forming step is a thin film solar cell module after the protective resin layer forming step The adhesive resin sealing material for preheating the heating roll to laminate, characterized by using the exhaust heat of the drying furnace.

  Here, in the thin film solar cell module manufacturing method of the present invention, the adhesive resin sealing material in the module adhesive layer forming step can be used as a slip sheet between the thin film solar cell modules wound around the winding shaft.

  Here, in the thin film solar cell module manufacturing method of the present invention, the surface of the module adhesive layer formed in the module adhesive layer forming step can be embossed.

  The thin film solar cell module manufacturing apparatus of this invention manufactures a thin film solar cell module using the thin film solar cell module manufacturing method in any one of this invention.

  According to the thin-film solar cell module manufacturing apparatus and the like of the present invention, the process of forming the protective resin layer F using the solvent-soluble fluororesin F on the light-receiving surface of the thin-film solar cell submodule, The module adhesive layer forming step using the adhesive resin sealing material J1 or the like can be continuously performed before being wound around the winding shaft R2. The module adhesive layer made of the adhesive resin sealing material J1 or the like formed on the protective resin layer F also serves as a slip sheet. For this reason, it is possible to prevent defects such as sticking to the guide roll in the roll-to-roll type conveyance in the prior art, wrinkles or folds when winding up into a roll shape without using a separate paper. Become. The formation of the protective resin layer F and the formation of the module adhesive layer with the adhesive resin sealing material J1 or the like on the protective resin layer F can be continuously performed before being wound around the winding shaft R2. For this reason, when unwinding the thin-film solar cell sub-module 1f in which the protective resin layer is formed from the roll by the solvent-soluble fluororesin coating F in the prior art in the subsequent process of the solvent-soluble fluororesin coating F coating step. It is possible to prevent defects due to peeling of the thin film due to sticking. As described above, the thin film solar cell module with excellent productivity that can prevent the decrease in yield due to poor conveyance due to sticking in the protective resin coating treatment of the light receiving surface of the thin film solar cell submodule without increasing the production cost. There is an effect that a manufacturing apparatus and a manufacturing method can be provided.

  Hereinafter, each embodiment will be described in detail with reference to the drawings.

  FIG. 1 is a schematic diagram for explaining a thin-film solar cell module manufacturing apparatus 20 and a manufacturing method according to Embodiment 1 of the present invention. In FIG. 1 and the following description, the same reference numerals as those in FIGS. In the thin film solar cell module manufacturing apparatus 20, as in the conventional thin film solar cell module manufacturing apparatus 10, a thin film solar cell module is manufactured using a flexible insulating substrate S. The thin film solar cell module manufacturing apparatus 20 is different from the conventional thin film solar cell module manufacturing apparatus 10 in that a protective resin layer F is formed using a solvent-soluble fluororesin F on the light receiving surface of the thin film solar cell submodule 1. And the step of forming the module adhesive layer with the adhesive resin sealing material J1 or the like on the protective resin layer F (before being wound around the winding shaft R2).

Main structure of thin-film solar cell module manufacturing apparatus 20 relating to the formation process of protective resin layer F.
It is the same as the conventional thin film solar cell module manufacturing apparatus 10. As shown in FIG. 1, the main configuration of the thin-film solar cell module manufacturing apparatus 20 relating to the process of forming the protective resin layer F is an unwinding shaft R1 for unwinding the thin-film solar cell module 1 manufactured in a roll shape, Solvent-soluble fluororesin paint F (protective resin layer F), gravure roll G for applying (transferring) solvent-soluble fluororesin paint F to the light-receiving surface of thin-film solar cell submodule 1 with an applicator roll, thin film A drying furnace HB maintained at 180 ° C. for heating and drying the solvent-soluble fluororesin paint F applied to the light-receiving surface of the solar cell submodule 1 and a solvent-soluble fluororesin paint F were applied to the light-receiving surface. It consists of a winding shaft R2 for winding the solar cell submodule 1f into a roll.

Step of forming protective resin layer F.
As shown in FIG. 1, first, the thin-film solar cell submodule 1 is unwound from the unwinding shaft R1. While the gravure roll G is pressed against the light receiving surface of the thin film solar cell submodule 1 at a constant pressure, the solvent-soluble fluororesin paint F is rotated while rotating in synchronization with the transport speed of the thin film solar cell submodule 1. It is applied to the light receiving surface of the thin-film solar cell submodule 1 to form a solar cell submodule 1f. The solar cell submodule 1f is guided to the drying furnace HB maintained at 180 ° C. via the guide rolls GR1 and GR2, and the soluble fluororesin paint F is heated and dried in the drying furnace HB to form the protective resin layer F. Is done.

Main configuration of thin-film solar cell module manufacturing apparatus 20 related to the module adhesive layer forming step.
As shown in FIG. 1, the main configuration of the thin-film solar cell module manufacturing apparatus 20 relating to the module adhesive layer forming step is that the adhesive resin sealing material J1 for unwinding the adhesive resin sealing material J1 and the like (2). The drive roll FD2, the thin film solar cell submodule 1f and the adhesive resin seal for supplying the equal unwinding shaft R3, the adhesive resin sealing material J1 and the like (2) in synchronization with the transport speed of the thin film solar cell submodule 1f Laminating roll RL1 (heating roll) having a heating function and a driving function for laminating the stop material J1 and the like (2), in particular, laminating, peeling belt TP connected to the laminating roll RL1, heating function and pressure It consists of a laminate roll RL2 (heating roll) having a function.

Module adhesive layer forming process.
As shown in FIG. 1, the adhesive resin sealing material J1 and the like (2) are unwound in synchronization with the transport speed of the thin-film solar cell submodule 1f sent from the drying furnace HB through the guide roll GR3. Unwinding from R3 by drive roll FD2. The unrolled adhesive resin sealing material J1 or the like (2) is heated and pressed together with the thin film solar cell submodule 1f between the peeling belt TP connected to the laminating roll RL1 and the laminating roll RL2, so that the thin film Adhesive resin sealing material J1 or the like (2) is laminated on the light receiving surface of the solar cell submodule 1f to form a module adhesive layer. The thin film solar cell submodule 1f (R) formed by sequentially laminating the protective resin layer F and the module adhesive layer on the light receiving surface controls the guide roll GR5, the amount of accumulation of the solar cell submodule 1f (R) being conveyed, and the like. Then, it is conveyed to the take-up shaft R2 via the dancer roll DR, the guide roll GR4, the drive roll FD, and the press roll P, which are movable rolls, and is taken up again in a roll shape.

  From the above, according to Example 1 of the present invention, the thin-film solar cell module manufacturing apparatus 20 forms the protective resin layer F using the solvent-soluble fluororesin F on the light-receiving surface of the thin-film solar cell submodule 1. And the process of forming the module adhesive layer with the adhesive resin sealing material J1 or the like on the protective resin layer F can be continuously performed before being wound around the winding shaft R2. For this reason, the thin film solar cell excellent in productivity which can prevent the fall of the yield accompanying the conveyance failure by sticking in the protective resin coating process of the light-receiving surface of the thin film solar cell submodule 1 without increasing production cost A module manufacturing apparatus and a manufacturing method can be provided.

  According to Example 1 of the present invention, the module adhesive layer made of the adhesive resin sealing material J1 or the like (2) formed on the protective resin layer F also serves as a slip sheet. For this reason, it is possible to prevent defects such as sticking to the guide roll in the roll-to-roll type conveyance in the prior art, wrinkles or folds when winding up into a roll shape without using a separate paper. Become.

  According to Example 1 of this invention, the formation process of the protective resin layer F and the formation process of the module adhesive layer by the adhesive resin sealing material J1 etc. on the protective resin layer F are wound up by the winding shaft R2. Can be done continuously before. For this reason, when unwinding the thin-film solar cell sub-module 1f in which the protective resin layer is formed from the roll by the solvent-soluble fluororesin coating F in the prior art in the subsequent process of the solvent-soluble fluororesin coating F coating step. It is possible to prevent defects due to peeling of the thin film due to sticking.

  In Example 1, it is preferable that the surface of the adhesive resin sealing material J1 or the like (2) has an embossed shape. With this embossed shape, it is possible to eliminate sticking to the guide roll or sticking to the guide roll, and to perform stable roll-to-roll conveyance.

  In Example 1, the heating rolls (laminate rolls RL1 and RL2) used for forming the module adhesive layer by the adhesive resin sealing material J1 and the like (2) are protected by the solvent-soluble fluororesin paint F. It is preferable to use the exhaust heat of the heating and drying furnace HB, which is one of the components on the resin layer F forming function side. This waste heat utilization method can reduce the power required for heating from room temperature and contribute to environmental problems.

  As an application example of the present invention, it can be applied to an apparatus for manufacturing a thin-film solar cell module.

It is a schematic diagram for demonstrating the thin film solar cell module manufacturing apparatus 20 and manufacturing method in Example 1 of this invention. It is a schematic diagram which shows an example of a thin film solar cell submodule. It is sectional drawing in the current collection hole H2 part of a thin film solar cell submodule. It is the schematic of the conventional thin film solar cell module manufacturing apparatus 10 which enforces the manufacturing method of the roll-to-roll system used for the protective resin layer F formation process of a thin film solar cell submodule light-receiving surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Thin film solar cell submodule, 1f Solar cell submodule which apply | coated solvent soluble type fluororesin coating material F to the light-receiving surface, 2 Adhesive resin sealing material J1, etc. 10 Conventional thin film solar cell module manufacturing apparatus, 20 this invention Thin film solar cell module manufacturing equipment.

Claims (4)

A thin-film solar cell module manufacturing method for manufacturing a thin-film solar cell module using a flexible type insulating substrate by a roll-to-roll method,
A protective resin layer forming step of forming a protective resin layer on the light-receiving surface of the thin-film solar cell module unwound from the unwinding shaft using a solvent-soluble fluororesin;
A module adhesive layer forming step of continuously forming a module adhesive layer using an adhesive resin sealing material on the protective resin layer formed by the protective resin layer forming step before winding onto the take-up shaft. Prepared ,
In the protective resin layer forming step, the solvent-soluble fluororesin on the light receiving surface of the thin film solar cell module is heated and dried by a drying furnace, and the module adhesive layer forming step is a thin film solar cell after the protective resin layer forming step. A method for producing a thin-film solar cell module , wherein exhaust heat of the drying furnace is used for preheating a heating roll for laminating an adhesive resin sealing material on the module.   2. The method of manufacturing a thin film solar cell module according to claim 1, wherein the adhesive resin sealing material in the module adhesive layer forming step is used as a slip sheet between the thin film solar cell modules wound around a winding shaft. Thin film solar cell module manufacturing method. 3. The method of manufacturing a thin film solar cell module according to claim 1, wherein the module adhesive layer surface formed in the module adhesive layer forming step has an embossed shape . A thin-film solar battery module manufacturing apparatus, comprising: a thin-film solar battery module manufactured using the thin-film solar battery module manufacturing method according to any one of claims 1 to 3 .

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