JP2004179397A - Method for manufacturing solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method for a glassless thin-type solar cell module having improved mass productivity by eliminating the problems of long-term restraint of a vacuum laminating apparatus and the squeeze-out of an adhesive resin sealing material, improving working efficiency and productivity, and preventing inferior appearance. <P>SOLUTION: A laminated sheet, where a solar cell is laminated via a sheet-like adhesive resin sealing material, between a surface protection member and a rear protection member is subjected to heating pressure treatment at a specific temperature for specific time by the vacuum laminating apparatus. The adhesive resin sealing material is subjected to primary curing treatment. After that, heating pressure treatment is made at a specific temperature for specific time by specific pressure by using a heating pressurization treating apparatus 90 that differs from the vacuum laminating apparatus. The adhesive resin sealing material is subjected to secondary curing treatment to manufacture the glassless thin-film solar cell module 80. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention provides a glass obtained by sealing a solar cell in which a plurality of solar cell elements are connected in series or in parallel between a front surface protection member and a back surface protection member via a sheet-like adhesive resin sealing material. The present invention relates to a method of manufacturing a thin thin solar cell module.
[0002]
[Prior art]
Thin-film solar cells are considered to be the mainstream of solar cells in the future because they are thin, lightweight, inexpensive in manufacturing cost, and easy to increase in area, so they are used not only for power supply but also for building roofs and windows. Demand is expanding for business use and general residential use. Roof tiles with solar cells have also been developed for general residential use.
[0003]
In recent years, research and development of a flexible solar cell using a plastic film has been promoted, and by utilizing this flexibility, mass production is possible by a roll-to-roll method or a step-roll method.
[0004]
The thin-film solar cell is usually used as a solar cell module. This module includes a protective layer on both the light-receiving side and the non-light-receiving side of the solar cell in order to seal the solar cell formed on the electrically insulating film substrate with an electrically insulating protective material. Is known.
[0005]
6 and 7 show an example of a schematic structure of a conventional solar cell module. FIG. 6 is a side sectional view of the solar cell module, and FIG. 7 is mounted on a frame having a U-shaped metal frame. FIG. 2 shows a side cross-sectional view of the solar cell module in a state where the solar cell module is in a state of being removed.
[0006]
In FIG. 6, a solar cell 1 has a plurality of solar cell elements connected in series or in parallel, a surface protection member 2 such as a glass plate on the light receiving surface side, and an ethylene monofluoride on both surfaces of an aluminum foil on the back surface side. (Trade name: Tedlar, manufactured by DuPont) Adhesive resin such as EVA (ethylene-vinyl acetate copolymer resin), which is provided with a back surface protective member 3 such as a moisture-proof protective sheet to which adhesive is adhered, and is excellent in adhesive sealability and inexpensive It is heat-sealed and sealed by the sealing material 4.
[0007]
In the solar cell 1, internal lead wires 5 and 6 are electrically connected to the positive (+) and negative (−) electrodes, and the internal leads 5 and 6 are bonded and fixed to the back surface protection member 3. The terminal box 7 is guided through the back surface protection member 3 and electrically connected to the core wires 9 and 10 of the cable 8 as an external lead inside the terminal box 7. Has formed.
[0008]
In addition, as the surface protection member 2, an organic material such as a translucent acrylic resin plate or a polycarbonate resin plate may be used in addition to an inorganic material such as a glass plate. In addition to the above-mentioned resin containing a metal foil, an organic film alone such as a fluorine-based film, a composite material obtained by laminating an organic film and a metal foil, or a metal such as a metal plate or a glass plate may be used as the back surface protective member 3. -In some cases, inorganic materials are used.
[0009]
FIG. 7 illustrates an example of a solar cell module mounted on a frame. In FIG. 7, a frame 12 is arranged around the solar cell module 11, and a peripheral portion of the solar cell module 11 is a cross section of the metal frame 12. It is inserted into a holding portion 12a having a U-shaped frame, and is fixed and held by an adhesive sealing material 13 injected so as to fill a gap. Here, as the adhesive sealing material 13, an adhesive elastic sealing material such as butyl rubber having heat fluidity or silicone rubber which becomes a solid after being cured in a liquid state is used, and the surface protection member 2 such as a glass plate and the frame 12 are used. Absorbs thermal expansion and suppresses moisture intrusion.
[0010]
Next, a method of laminating (thermally sealing and sealing) each component related to the method of manufacturing the solar cell module 11 will be described with reference to FIG. In FIG. 8, the solar cell module 11 includes a surface protection member 2, an adhesive resin sealing material 4, a solar cell 1 to which leads 5 and 6 are attached in advance, an adhesive resin sealing material 4, and a back surface protection member 3. They are sequentially laminated and placed in the vacuum laminating apparatus 100. Thereafter, the upper housing 101 of the vacuum laminating apparatus 100 is closed and hermetically closed, heated to a predetermined temperature by the heating plate 103, and the module 11 is discharged from the exhaust pipe 104 attached to the lower housing 102 by an exhaust device (not shown). The air in the space 105 where it is placed is exhausted and kept in a vacuum.
[0011]
At the same time, the air in the space 108 formed by the rubber diaphragm 107 and the upper housing 101 is exhausted from the air supply / exhaust pipe 106 attached to the upper housing 101 to create a vacuum. It is stuck on the inner wall surface 109. In this state, after the solar cell module 11 is heated at a predetermined temperature for a predetermined time, air is introduced from a supply / exhaust pipe 106, and a pressure difference (substantially atmospheric pressure difference) between the space 105 and the space 108 causes the solar cell module 11 to be heated. Is vacuum-pressed by a rubber diaphragm 107 to form a solar cell module 11 having a sectional structure shown in FIG.
[0012]
Regarding the structure and manufacturing method of the solar cell module, various structures and manufacturing methods other than the above are employed. FIG. 5 is a schematic cross-sectional view schematically showing various structures of the solar cell module, showing only main members.
[0013]
FIG. 5A corresponds to a solar cell module having the structure shown in FIG. 6, in which 21 is a solar cell, 22 is a surface protection member (glass plate), and 23 is a back material (aluminum foil laminated poly-foil) as a back surface protection member. Vinyl chloride 24 denotes an adhesive resin sealing material (EVA).
[0014]
FIG. 5 (b) corresponds to a so-called super straight structure in which solar cells are formed directly on a glass substrate, 31 is a glass substrate solar cell, 33 is a backing material (aluminum foil laminated polyvinyl fluoride), and 34 is an adhesive. 1 shows a conductive resin sealing material (EVA).
[0015]
FIG. 5C shows a so-called substrate structure in which a solar cell is formed on a SUS substrate or a plastic substrate, and a plastic protective film is used as a surface protective member. A surface protection film (ETFE or FEP), 43 indicates a back structure support (surface-treated AL-zinc steel plate), and 44 indicates an adhesive resin sealing material (EVA).
[0016]
Further, FIG. 5D shows a flexible module using a plastic film protective film as a front surface protection member and a rear surface protection member, 51 is a solar cell, 52 is a surface protection film (ETFE or FEP), 53 denotes a back surface protective film (ETFE, FEP, PVF, etc.), and 54 denotes an adhesive resin sealing material (EVA). Further, FIG. 5E shows the front surface protection member and the rear surface protection member of FIG. 5D with a glass nonwoven fabric 65 added as a reinforcing layer.
[0017]
In addition to the above, there are various solar cell module structures, and a structure suitable for needs is adopted. As will be described in detail later, the present invention is directed to a method without using a glass plate, that is, a glassless thin solar cell module as shown in FIGS. . The back structure support member 43 shown in FIG. 5C is shown as a thick plate, but uses a thin steel plate.
[0018]
FIG. 4 is a schematic configuration diagram relating to a laminated sheet when the glassless thin solar cell module is formed, and shows an example of a module using a steel plate as a back structure support (see FIG. For details, see, for example, Patent Document 1.
[0019]
FIG. 4A is a plan view of the laminated sheet for a solar cell module, and FIG. 4B is a cross-sectional view along XX in FIG. 4A. In FIG. 4, on both sides of a solar cell 70 having a photoelectric conversion unit formed on a flexible substrate, internal wirings 72 are arranged, and connected to the back electrode of the solar cell 70 via auxiliary wirings 73. These are sealed with a sheet-like adhesive resin sealing material 25 such as EVA, and the light incident side is covered with a weather-resistant protective film 74 such as ETFE (ethylene tetrafluoride polymer). The other side is covered with a back surface protection material such as a steel plate to constitute a solar cell module 80 with a steel plate as a whole.
[0020]
As a method for manufacturing the solar cell module as described above, after laminating and assembling into a structure as shown in FIG. 4B, the sheet-shaped adhesive resin sealing material 25 is softened and melted to a hardening step, and from room temperature to room temperature. , Etc., were continuously performed in the same vacuum laminating apparatus.
[0021]
[Patent Document 1]
JP 2000-349308 A (pages 2 to 5, see FIGS. 1 to 8)
[0022]
[Problems to be solved by the invention]
By the way, the method for manufacturing a solar cell module in which various processes are continuously performed in the same vacuum laminating apparatus has the following problems.
[0023]
First, since EVA is cross-linked with a peroxide, the cross-linking time takes about 10 to 30 minutes, and if a vacuum treatment and a heating / cooling step are included, the production time becomes as long as about 60 to 70 minutes. The device will be restrained for a long time. Therefore, when mass-producing the solar cell module, there is a problem that productivity is low, and the manufacturing cost is high.
[0024]
On the other hand, in recent years, as a manufacturing method of a glass cover module type using a glass plate, in a vacuum laminating apparatus, the adhesive resin sealing material is taken out in the middle of the completion of melting, and the adhesive resin sealing material is separated by another heating device (dryer or the like). It is being considered to complete the hardening of the stop material. In this case, although the productivity is improved without restraining the vacuum laminating device for a long time, the adhesive resin sealing material (EVA) protrudes from the module during the curing by the another heating device. There is a problem that the portion soils the heating device and the like, and there is a problem that the productivity is reduced due to the adverse effect of the contamination.
[0025]
In the case of the above-mentioned glass cover module type, in order to eliminate the problem of the contamination, the dimensions of the protective film (3 in FIG. 6) are increased as in the module shown in FIGS. , And EVA, the protruding portion is received here, and the protruding portion is deleted later.
[0026]
The protruding problem is a problem that also occurs in a glassless thin solar cell module, but in the case of a glassless, it is required that the rigidity is small, the waist is weak, and the thickness dimension of the module is also small. Therefore, it is difficult to solve the problem by the method using the dimension increase of the protective film. In addition, since the rigidity is low, there is a problem that it is difficult to transport to another heating device, and continuous processing must be performed in the same vacuum laminating device.
[0027]
The present invention has been made in view of the above points, and an object of the present invention is to solve the problem of restraining the vacuum laminating device for a long time and the problem of the sticking out of the adhesive resin sealing material. It is an object of the present invention to provide a method for manufacturing a glassless thin solar cell module which is capable of improving productivity and preventing appearance defects and which is excellent in mass productivity.
[0028]
[Means for Solving the Problems]
In order to solve the above-mentioned problem, in the present invention, a solar cell having a plurality of solar cell elements connected in series or in parallel between a front surface protection member and a back surface protection member is formed into a sheet-like adhesive resin sealing material. A method for manufacturing a glass-less thin solar cell module sealed by a method comprising the following steps (the invention of claim 1).
1) A laminated sheet obtained by laminating a solar cell between a surface protection member and a back surface protection member via a sheet-like adhesive resin sealing material is heated and pressed at a predetermined temperature for a predetermined time by a vacuum laminating apparatus. And a step of performing a primary curing treatment on the adhesive resin sealing material (primary curing treatment step).
2) The laminated sheet after the primary curing process is heated and pressed at a predetermined pressure and a predetermined temperature for a predetermined time by a heating and pressure processing device different from the vacuum laminating device, and the adhesive resin sealing material is removed. Step of performing a secondary curing treatment (secondary curing treatment step).
[0029]
According to the above method, in the primary curing step by the vacuum laminating apparatus, after bonding the laminated sheet in a relatively short time without causing the crosslinking reaction to proceed so much, the laminate sheet is carried into the heat and pressure treatment apparatus, and the secondary curing step is performed. Since the cross-linking is completed to form the module, the problem of long-term restraint of the vacuum laminating apparatus and the problem of sticking out of the adhesive resin sealing material can be eliminated, and workability, productivity and appearance defects can be prevented.
[0030]
As an embodiment of the invention of claim 1, the following inventions of claims 2 to 7 are preferable. That is, in the manufacturing method according to claim 1, the adhesive resin sealing material is EVA (ethylene-vinyl acetate copolymer resin), the predetermined temperature in the primary curing step is 140 to 160 ° C., and the predetermined time Is 5 to 10 minutes (the invention of claim 2). The degree of cross-linking and curing of EVA varies depending on the temperature and time, but the above range is preferable in order to adhere the laminated sheet in a relatively short time so that the laminated sheet can be transported.
[0031]
Further, in the manufacturing method according to the first or second aspect, at the time of the primary curing treatment step, a release sheet is overlapped on both main surfaces of the laminated sheet and processed (the invention of the third aspect). This release sheet has not only a function as a separator in the multiple module processing of the invention of claim 5 described later but also a function of strengthening the rigidity of the laminated sheet in the glassless method, thereby improving workability.
[0032]
Furthermore, in the manufacturing method according to any one of claims 1 to 3, the adhesive resin sealing material is EVA, and a predetermined temperature in the secondary curing process is 140 to 160 ° C, and a predetermined pressure is set. Is set to 0.001 to 0.1 MPa (the invention of claim 4). When the pressure is less than 0.001 MPa, no pressurizing effect can be obtained. This is because there are places where pressure is unlikely to be applied, such as at the boundary between the presence and absence of a solar cell, and the film thickness may be non-uniform, which causes a problem of causing poor appearance. On the other hand, if it is larger than 0.1 MPa, the film thickness becomes thin due to over-pressurization, there is a difficulty in dimensional stability, and there is a problem that EVA protrudes from the edge of the substrate.
[0033]
Further, in the manufacturing method according to any one of claims 1 to 4, in the secondary curing process, a plurality of stacked sheets after the primary curing process are provided on both main surfaces of each laminated sheet. The laminated body laminated via the release sheet is subjected to heat and pressure treatment collectively (the invention of claim 5). Thereby, the working time and cost can be reduced.
[0034]
Furthermore, in the manufacturing method according to claim 5, each of the release sheets in the laminate is disposed on each of both main surfaces of each of the laminate sheets, and each of the release sheets in the adjacent laminate sheet. In the meantime, the secondary curing treatment is performed by arranging rubber plates in between (the invention of claim 6). This allows the rubber plate to act as a cushioning material, thereby preventing appearance defects such as wrinkles from occurring.
[0035]
Furthermore, in the manufacturing method according to any one of claims 3 to 6, the release sheet is made of an embossed fluororesin-impregnated glass cloth (the invention of claim 7). This facilitates peeling and improves strength.
[0036]
BEST MODE FOR CARRYING OUT THE INVENTION
Examples of the present invention will be described below together with comparative examples. The configuration of the solar cell module used in Examples and Comparative Examples described later is the same as that formed from the laminated sheet shown in FIG.
[0037]
(Example)
In FIG. 4B, the protective film 74 is an ETFE weather-resistant film having a thickness of 0.025 mm, and EVA having a thickness of 0.4 mm is used as the adhesive resin sealing material 75. As the internal wiring 72, a metal foil made of Sn / Cu / Sn material and having a thickness of 0.10 mm and a width of 8 mm was used. As the internal wiring 72, a solder-plated Cu material can be used. As the auxiliary wiring 73, a tape having a width of 8 mm in which a conductive adhesive was applied to a laminate of a PET film having a thickness of 0.025 mm and aluminum having a thickness of 0.030 mm was used.
[0038]
In the structure as shown in FIG. 4B, first, the protective film 74 is set on an embossed release sheet 91 (manufactured by Chuko Kasei Co., Ltd., trade name: Chuko Flow: FGF-400) shown in FIG. After assembling the resin encapsulant 75, the solar cell 10 having the adhesive resin encapsulant 75 having a thickness of 0.3 mm preliminarily laminated on the surface side and the internal wiring 72 are set at predetermined positions, and the auxiliary wiring is set. At 73, the solar cell 10 was electrically connected to the internal wiring 72. Next, after the adhesive resin encapsulant 75 is placed, a galvalume steel plate (manufactured by Kawa iron plate, trade name: Regino Color Shincha) 71 is placed, and finally the embossed release sheet 91 is set to complete the assembly. I do.
[0039]
Assemble a predetermined number of sheets, set them in parallel in a vacuum laminating apparatus, perform primary curing under the prescribed conditions (eg, evacuate for 5 minutes, press for 1 minute, and primary cure for 5 minutes) at a temperature of 150 ° C. Was temporarily taken out together with the embossed release sheet 91 and temporarily stored at room temperature.
[0040]
After repeating the above-described steps to produce ten or more finished products of the primary curing process, as shown in the schematic diagram of FIG. The release sheet 91 and the rubber plate 92 were assembled in this order between the upper and lower plates 93, and the solar cell modules 80 set between the primary cured release sheets were assembled in a predetermined number of steps while sequentially inserting the rubber plate 92 therebetween. Next, the pressure was adjusted and the pressure was adjusted so that the surface pressure became 0.05 MPa.
[0041]
The press simple jig in which the solar cell modules were stacked and assembled was set in a heating and pressurizing apparatus 90 as shown in FIG. 2, and a secondary curing treatment was performed at a temperature of 150 ° C. for about 1 hour. After that, a switch for heat treatment (not shown) of the heat and pressure treatment device 90 was turned off, and the temperature was gradually cooled until the temperature dropped to 60 ° C., thereby producing a solar cell module with a steel plate.
[0042]
(Comparative example)
A vacuum laminating process was performed by the laminating apparatus shown in FIG. 8 according to a laminating condition profile (vacuum evacuation for 15 minutes, press for 1 minute, curing process for 20 minutes) shown in FIG. The working time at this time required 65 minutes.
[0043]
The time required for the manufacturing process of the solar cell module manufactured according to the above-described embodiment is from about assembling to curing removal is within about 20 minutes in terms of one module, and the process time is significantly reduced as compared with the comparative example of the conventional method. I was able to. Further, the conventional method has a problem of contamination of the device due to the protrusion of the EVA and a reduction in productivity associated therewith. However, the problem of the contamination of the device has been solved by stacking fluororesin release sheets on the upper and lower sides of the module. .
[0044]
Further, in the method for manufacturing the solar cell module of the comparative example, the temperature raising step, the softening / melting of the adhesive resin sealing material 75 from the curing, and the step of cooling to room temperature are continuously performed in the same vacuum laminating apparatus. The device is restrained for over an hour and can only be manufactured 7-8 cycles / day. Therefore, the productivity is low and the cost is high. However, as in the above embodiment of the present invention, a method of evacuating for 5 minutes, pressing for 1 minute, performing primary curing for 5 minutes, taking out and temporarily storing in a high temperature state. If 28 is adopted, 28 to 32 cycles / day can be manufactured. Therefore, the productivity is remarkably improved as compared with the related art, and the cost can be reduced accordingly.
[0045]
【The invention's effect】
According to the present invention, as described above, a laminated sheet obtained by laminating solar cells via a sheet-like adhesive resin sealing material between a front surface protection member and a back surface protection member is formed at a predetermined temperature by a vacuum laminating apparatus. Heat and pressure treatment for a predetermined time, primary curing treatment of the adhesive resin sealing material, and then heat and pressure at a predetermined pressure and a predetermined temperature for a predetermined time by a heat and pressure processing device different from the vacuum laminating device. By treating the adhesive resin encapsulant for secondary curing, to produce a glass-less thin solar cell module,
The problem of restraining the vacuum laminating device for a long time and the problem of sticking out of the adhesive resin sealing material can be solved, and the workability and productivity can be improved and appearance defects can be prevented.
[Brief description of the drawings]
FIG. 1 is a diagram showing a stack of modules according to an embodiment of the present invention. FIG. 2 is a schematic diagram of a heating and pressurizing apparatus according to an embodiment of the present invention. FIG. FIG. 4 is a diagram showing a lamination process condition profile. FIG. 4 is a schematic configuration diagram relating to a laminated sheet of a solar cell module to which the present invention is applied. FIG. 5 is a schematic side sectional view of a schematic configuration of various conventional solar cell modules. 6 is a side sectional view of a schematic configuration showing an example of a conventional solar cell module. FIG. 7 is a side sectional view of a schematic configuration of a solar cell module in which the solar cell module of FIG. 6 is mounted on a frame. Side sectional view of a vacuum laminating apparatus related to the module manufacturing method.
70: Solar cell, 71: Steel plate, 74: Protective film, 75: Adhesive resin sealing material, 80: Solar cell module, 90: Heat and pressure treatment device, 91: Release sheet, 92: Rubber plate, 93: Plate , 100: vacuum laminating apparatus.

Claims (7)

A glassless thin solar cell obtained by sealing a solar cell in which a plurality of solar cell elements are connected in series or in parallel between a surface protection member and a back surface protection member via a sheet-like adhesive resin sealing material. A method for manufacturing a solar cell module, comprising the following steps in a method for manufacturing a battery module.
1) A laminated sheet obtained by laminating a solar cell between a surface protection member and a back surface protection member via a sheet-like adhesive resin sealing material is heated and pressed at a predetermined temperature for a predetermined time by a vacuum laminating apparatus. And a step of performing a primary curing treatment on the adhesive resin sealing material (primary curing treatment step).
2) The laminated sheet after the primary curing process is heated and pressed at a predetermined pressure and a predetermined temperature for a predetermined time by a heating and pressure processing device different from the vacuum laminating device, and the adhesive resin sealing material is removed. Step of performing a secondary curing treatment (secondary curing treatment step). The manufacturing method according to claim 1, wherein the adhesive resin sealing material is EVA (ethylene-vinyl acetate copolymer resin), and a predetermined temperature in the primary curing step is 140 to 160 ° C, and a predetermined time is 5 ° C. A method for producing a solar cell module, wherein the method is performed for 10 minutes to 10 minutes. 3. The method according to claim 1, wherein in the primary curing step, a release sheet is overlapped on both main surfaces of the laminated sheet and processed. 4. 4. The method according to claim 1, wherein the adhesive resin sealing material is EVA, a predetermined temperature in the secondary curing process is 140 to 160 ° C., and a predetermined pressure is 0. 001 to 0.1 MPa, a method for manufacturing a solar cell module. In the manufacturing method according to any one of claims 1 to 4, in the case of the secondary curing treatment step, the laminated sheet after the primary curing treatment step is a plurality of stages, and a release sheet is provided on both main surfaces of each laminated sheet. A method for manufacturing a solar cell module, comprising: performing a heating and pressurizing treatment on a stacked body that has been stacked via a batch. In the manufacturing method according to claim 5, each release sheet in the laminated body is disposed for each one of both main surfaces of each laminated sheet, and between each release sheet in an adjacent laminated sheet, A method for manufacturing a solar cell module, wherein a rubber plate is provided and the secondary curing treatment is performed. The method according to any one of claims 3 to 6, wherein the release sheet comprises an embossed glass cloth impregnated with a fluorine resin.

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