JP2005086008A - Method for repairing solar battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To repair any flaw generated in a solar battery without damaging its appearance. <P>SOLUTION: This solar battery module 10 is configured by laminating thermal crosslinked sealing materials 12 made of first resin and a protecting film 13 whose melting point is higher than that of the sealing materials 12 on a photoelectric converting element 11, and a repair film 17 is arranged so that a flaw 16 generated in the solar battery module 10 can be covered to repair the flaw 16. Then, the repair film 17 is heated and press-welded at a temperature which is lower than any of the thermal crosslinked temperature of the sealing materials 12, the melting point of the protecting film 13 and the melting point of the repair film 17. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for repairing a solar cell module, and more particularly to a method for repairing a solar cell module using a thermally crosslinkable thermoplastic resin as a sealing material.

  The solar cell module may be damaged due to vibration or dropping during distribution transportation. In particular, the light-receiving surface side may be damaged due to mistakes during construction or flying objects such as a kite during long-term installation.

  If the damaged solar cell module is used as it is, the sealing material or photoelectric conversion blocking peels off due to moisture or water vapor entering from the scratch, or the sealing material additive flows out and the sealing material is Deterioration of properties may occur, such as deterioration. It can also cause ground faults through moisture.

  In particular, a solar cell module in which a photoelectric conversion element is affixed on a steel plate or a tile and glass is not provided on the light incident side is only a resin film on the light incident side, and is easily damaged. Causes of this damage include impacts such as dropping during logistics, dropping tools during construction, collision of scaffolding members at the end of construction, and impact of flying objects on solar cell modules during long-term use. It is done.

Conventional repair methods for solar cell modules include the following.
For example, Patent Document 1 discloses performing partial repair by remelting with the sealing material being non-crosslinked. Specifically, instead of a cross-linked product of ethylene-vinyl acetate copolymer (EVA) used as a general sealing material for solar cell modules, tetrafluoroethylene (TFE), hexafluoropropylene (HFP), Disclosed is a fluoropolymer encapsulant comprising a vinylidene fluoride (VDF), tetrafluoroethylene (TFE), or vinylidene fluoride (VDF) as a main component and having a melting point. According to the document, a solar cell module using a cross-linked product of ethylene-vinyl acetate copolymer (EVA) as a sealing material cannot be remelted, so that partial repair is impossible. On the other hand, sealing of fluoropolymer having a melting point mainly composed of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), vinylidene fluoride (VDF) or tetrafluoroethylene (TFE), vinylidene fluoride (VDF). By sealing the photoelectric conversion element with a material, the sealing material is remelted because of non-crosslinking, and partial repair is possible.

  Patent Document 2 discloses that a solar cell module sealing material using a sealing material made of a thermoplastic resin is remelted and partially repaired. In patent document 2, the problem of patent document 1 is pointed out as follows.

  The sealing material shown in Patent Document 1 has a wide melting point of 100 to 300 ° C., and in particular, it is difficult to easily heat and re-melt a sealing material having a melting point of 200 ° C. or higher. is there. Furthermore, even if the above-mentioned resin has a low melting point, the melt flow rate is low and the fluidity due to heating is poor. Therefore, repair is difficult. On the other hand, if the melt flow rate is too high, the flow of the sealing material by heating is large, and the film thickness of the sealing material heated for repair may be too thick or too thin. .

  On the other hand, in a method for repairing a solar cell module sealed with a sealing material made of a thermoplastic resin, the melt flow rate of the sealing material is 5 to 35 g / kg at a test temperature of 190 ° C. and a test load of 21.18 N of JIS K7210. 10 minutes, repairing scratches on the light-receiving surface or non-light-receiving surface by heating prevents the sealing material from flowing more than necessary by heating for repairing the solar cell module, and the film thickness of the sealing material is It is said that it is possible to prevent accumulation of dust and the like on the surface of the solar cell module due to non-uniformity, and to prevent deterioration in conversion efficiency and significant deterioration in appearance.

Furthermore, Patent Document 3 discloses repairing a solar cell module by covering a scratch on the front surface or the back surface with an adhesive tape made of a base material and an adhesive, or a repair member made of a paint. In order to prevent regular reflection, it is described that when the surface of the solar cell module is embossed, the repair member is subjected to a waving process in advance.
JP-A-11-106589 (paragraph numbers [0025] to [0032]) JP 2002-26358 A (paragraph numbers [0009] to [0011], [0055]) Japanese Patent Laid-Open No. 11-307799 (paragraph numbers [0012] to [0035])

  However, the methods disclosed in Patent Document 1 and Patent Document 2 cannot use a material such as thermally crosslinkable EVA that has high weather resistance and is inexpensive as a sealing material. In addition, if a structure using a protective film such as fluororesin is used to increase the weather resistance, scratches will remain on the protective film unless the temperature is raised to the high melting point of the protective film, resulting in incomplete repair. When the temperature was raised to a certain level, there was a problem that the protective film and the sealing material were mixed and the repair was incomplete.

  On the other hand, in the repair method of repairing a repair member such as Patent Document 3 using an adhesive tape, when the solar cell module surface is provided with an emboss for preventing regular reflection, the adhesive tape is made of an adhesive and It adheres to the battery module surface and does not become familiar with the module surface. Therefore, an air layer is formed between the adhesive tape and the solar cell module according to the shape of the unevenness due to the embossing, and water enters the air layer during rain. As a result, there are problems such as deterioration of the module characteristics and ground fault, and the appearance of repaired parts. In addition, even when the repair member is subjected to a waving process, it is necessary to match the concavo-convex shape and the waving process shape, and there is a problem that the repair is difficult.

  Furthermore, when the heating temperature is equal to or higher than the melting point of the protective film or the base material of the adhesive tape, the protective film or the adhesive tape is wrinkled and the appearance is poor, and when the treatment is performed at a temperature higher than the crosslinking temperature of the sealing material, It has become clear that the problem of enlarging plastic deformation of the sealing material also arises.

  This invention is made | formed in view of such a subject, and it aims at providing the repair method of the solar cell module which can repair the damage | wound produced in the solar cell module, without impairing an external appearance. .

  In the present invention, in order to solve the above problem, a solar cell module in which a photoelectric conversion element is laminated with a sealing material made of at least a thermally crosslinkable first resin and a second resin having a melting point higher than that of the sealing material. In the repair method, a repair member is provided so as to cover a scratch generated on the light-receiving surface or non-light-receiving surface of the solar cell module, and the repair member includes a crosslinking temperature of the sealing material, a resin having a high melting point, and the repair. There is provided a method for repairing a solar cell module, wherein the member is heated and bonded at a temperature lower than any of the melting points of the members.

  According to such a method, the repair member is provided so as to cover the wound, and the repair member is further heated at a temperature lower than any of the crosslinking temperature of the sealing material and the melting point of the second resin and the repair member. Thus, the repair member covers the scratch while following the unevenness of the light receiving surface or the non-light receiving surface. In addition, the sealing material is prevented from being deformed, and the second resin and the repair member are prevented from being damaged due to wrinkles.

  According to the repair method of the solar cell module of the present invention, a solar cell module in which a photoelectric conversion element is laminated with a sealing material made of at least a thermally crosslinkable first resin and a second resin having a higher melting point than that of the photoelectric conversion element. In order to repair the generated scratch, a repair member is provided so as to cover the scratch, and heated and crimped at a temperature lower than the thermal crosslinking temperature of the sealing material, the melting point of the second resin, and the melting point of the repair member. It is possible to repair the scratch without deteriorating the appearance.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram for explaining a method for repairing a solar cell module according to an embodiment of the present invention, and shows a cross-sectional configuration diagram of the solar cell module.

  The solar cell module 10 described in the embodiment of the present invention includes a sealing material 12 made of a thermally crosslinkable first resin on the light incident side on the photoelectric conversion element 11 and a melting point higher than that of the sealing material 12. 2 resin (hereinafter referred to as a protective film) 13 is laminated, and a sealing material 14 and a reinforcing plate 15 made of a steel plate are sequentially laminated on a non-incident surface (opposite surface).

  As the photoelectric conversion element 11, for example, a metal electrode is formed on a polyimide substrate, and a photoelectric conversion element having a tandem structure of amorphous silicon (hereinafter referred to as a-Si) / amorphous silicon germanium (hereinafter referred to as a-SiGe) is used. The formed one is used. For example, ITO (Indium-Tin Oxide) is used for the transparent electrode on the light incident side.

In addition, as a substrate of the photoelectric conversion element 11, PET (Poly (Ethylene Terephthalate)), PEN (Poly (Ethylene Naphthalate)), polyamide, polycarbonate, PBT (Poly (Buthylene Terephthalate)), PPS (Poly (Phenylene Sulfide)) ), A liquid crystal polymer, a resin film such as PEI (Poly (Ether Imide)), PAI (Poly (Amide Imide)), a stainless steel substrate, or a glass substrate may be used. Further, the tandem structure of a-Si / a-SiGe is not limited, and amorphous carbon (hereinafter referred to as aC), a-Si, microcrystalline silicon (hereinafter referred to as μc-Si), μc− SiGe, μc-SiC, μc-Ge, or the like may be used. A photoelectric conversion element having a single structure or a three-layer tandem structure can also be used. As the transparent electrode, a transparent conductive film such as SnO ₂ (tin oxide) or ZnO (zinc oxide) can be used.

  The first resin constituting the sealing materials 12 and 14 is a thermally crosslinkable resin, and uses EVA (ethylene-vinyl acetate copolymer) containing a crosslinking material, which has high weather resistance and is low in price. Is desirable.

  The second resin constituting the protective film 13 has a melting point higher than that of the sealing materials 12 and 14, and for example, it is desirable to use an ETFE (tetrafluoroethylene / ethylene copolymer) film having high weather resistance. . PTFE (tetrafluoroethylene resin), FEP (tetrafluoroethylene / hexafluoropropylene copolymer), PFA (tetrafluoroethylene / perfluoroalkyl vinyl ether copolymer), PVDF (polyvinylidene fluoride), PVF ( A film such as polyvinyl fluoride) may be used.

  The reinforcing plate 15 is not limited to a steel plate, but may be a tile material, an aluminum plate, concrete, a stainless steel substrate, or the like. Moreover, it can also be set as the structure which uses only a protective film, without using the reinforcement board 15. FIG. Further, in addition to fixing the reinforcing plate 15 at the same time using the sealing material 14, the reinforcing material may be fixed by an adhesive or screwing.

In the above description, the light incident surface side of the photoelectric conversion element 11 has a two-layer structure of the sealing material 12 and the protective film 13 on the surface, but a glass fiber nonwoven fabric or the like may be inserted to have a three-layer structure or more.
In the solar cell module 10 configured in this way, scratches 16 are generated due to flying objects. In the embodiment of the present invention, in order to repair this scratch 16, a repair member 17 is provided on the light receiving surface of the solar cell module 10 so as to cover the scratch 16.

  The repair member (hereinafter referred to as a repair film) 17 is, for example, an adhesive tape made of a base material and an adhesive material. Since the adhesive tape is required to have weather resistance, it is desirable to use ETFE similarly to the protective film 13. Moreover, you may use films, such as PTFE, FEP, PFA, PVDF, and PVF. Also, since the adhesive material still needs weather resistance, it is desirable to use an acrylic adhesive material. In addition, a butyl rubber-based material, a silicone-based material, or a thermoplastic material may be used as the adhesive material.

  When the surface on the incident side of the solar cell module 10 has irregularities, the repair film 17 cannot follow these irregularities simply by pasting the repair film 17. Therefore, a space is created between the repair film 17 and the protective film 13. Then, when used outdoors, rainwater reaches the scratch through the recess, the solar cell module 10 is grounded, the additive of the sealing materials 12 and 14 flows out, the weather resistance is lowered, and the metal electrode is corroded. Problems arise.

  Therefore, in the embodiment of the present invention, the repair film 17 is heated by using a heating roll or the like, and is bonded by pressure so as to cover the scratches generated on the incident surface of the solar cell module 10. By heating, the viscosity of the adhesive material decreases, the protective film 13 and the repair film 17 become familiar, the space generated between them is reduced, and rainwater does not enter. Moreover, the repair site | part of the solar cell module 10 is made by making this heating temperature into temperature lower than any of the crosslinking temperature of the sealing materials 12 and 14 before bridge | crosslinking, melting | fusing point of the protective film 13, and melting | fusing point of the base material of an adhesive tape. Can be prevented from being deformed. Further, the deformation can be further suppressed by setting the temperature to be equal to or lower than the melting point of the sealing materials 12 and 14 before crosslinking.

  In the above description, the repair of the scratches generated on the light receiving surface of the solar cell module 10 has been described. However, in the case where only the protective film is used without using the reinforcing plate 15 on the non-light receiving surface side, the non-light receiving surface is used. It is also possible to repair the wound generated in the same way.

The unevenness as described above may be intentionally embossed on the light-receiving surface of the solar cell module in order to prevent regular reflection (anti-glare effect) or for deaeration during sealing.
Below, the repair method of the solar cell module which formed the unevenness | corrugation (henceforth an emboss structure may be called hereafter) by embossing is demonstrated.

FIG. 2 is a plan view for explaining a method for repairing a scratch generated in a solar cell module in which a light receiving surface is embossed.
FIG. 3 is a cross-sectional view taken along line AA in FIG.

  As in FIG. 1, the solar cell module 20 has a sealing material 22 and a protective film 23 laminated on the light incident side on the photoelectric conversion element 21, and a sealing material 24 and a steel plate on the non-incident surface (opposite surface). The reinforcing plates 25 are sequentially laminated. However, an embossed structure is formed on the sealing material 22 by embossing. The protective film 23 is also formed so as to follow this embossed structure.

When such a damage 26 occurs in the solar cell module 20, a repair film 27 is provided on the light receiving surface of the solar cell module 10 so as to cover the damage 26 in order to repair the damage 26.
The normal embossing has a height of about 0.05 to 0.5 mm, for example. In such a structure, the repair film 27 cannot follow the recess 23a due to the embossed structure. Therefore, a space 28 is formed between the repair film 27 and the protective film 23 as shown in FIG. As described above, such a space 28 causes problems such as a ground fault, a decrease in weather resistance, and corrosion of the metal electrode, and also causes a problem that the reflectance is large and the appearance is deteriorated because it looks whitish. Therefore, next, the repair film 27 is heated and pressed to fill the space 28.

FIG. 4 is a plan view of the solar cell module after the heat treatment.
FIG. 5 is a cross-sectional view taken along line AA in FIG.
As described above, in the heat treatment, for example, the repair film 27 is heated by using a heating roll or the like, and is bonded by pressure so as to cover the scratches 26 generated on the incident surface of the solar cell module 20. By heating, the viscosity of the adhesive material decreases, and the protective film 23 and the repair film 27 become familiar as shown in FIG. 5, and the space 28 generated by the recess 23a due to the embossed structure is filled with the repair film 27 and decreases. Rainwater will never enter. Further, the appearance of the space 28 is improved as shown in FIG.

  In addition, the repair site | part of the solar cell module 20 is made by making this heating temperature into temperature lower than any of the crosslinking temperature of the sealing materials 22 and 24 before bridge | crosslinking, melting | fusing point of the protective film 23, and melting | fusing point of the base material of an adhesive tape. Can be prevented from being deformed. Further, the deformation can be further suppressed by setting the temperature to be equal to or lower than the melting point of the sealing materials 22 and 24 before crosslinking.

  Hereinafter, the result of the outdoor exposure test in the solar cell module repaired by changing various conditions will be shown.

Table 1 above is a table showing the results of outdoor exposure tests on solar cell modules repaired by changing various conditions.
(Experimental example 1) The damage | wound of the solar cell module using the photoelectric conversion element produced on the polyimide substrate was repaired.

  The solar cell module is composed of an a-Si / a-SiGe tandem cell on a polyimide substrate. On the light incident surface side, 0.8mm thick EVA containing a cross-linking material as a sealing material, protection As a film, ETFE having a thickness of 0.03 mm is sequentially laminated, and an EVA containing a cross-linking material having a thickness of 0.8 mm and a stainless steel substrate having a thickness of about 1 mm are sequentially laminated on the opposite surface. These are heated at 150 ° C. for 20 minutes, and 90% or more are crosslinked. In addition, the embossed structure was provided in the surface using the peeling film shape | molded at the time of lamination. The embossed structure was about 0.3 mm in both width and height.

  This solar cell module was damaged by the following method. A load of 2.4 kgf was applied to a needle having a tip angle of approximately 60 ° C. and kept stationary for 30 seconds, and then traversed at a speed of 30 mm / min to be injured with a length of 30 mm.

  We repaired this wound. For repair, use a fluororesin film with a thickness of about 50 μm as the base material, and use an adhesive tape using an acrylic adhesive material. Cut the adhesive tape from the scratch so that the creepage distance at the end of the repair film is 10 mm and bond I went there. At the time of adhesion, the repaired part and the repair film were heated to 70 ° C. below the melting point of the sealing material before crosslinking by using a heating roll, and a pressure of 0.1 MPa was applied for adhesion. In addition, the softening temperature of the used sealing material is 80 degreeC, and bridge | crosslinking temperature is about 150 degreeC. This repair reduced the space between the surface of the protective film and the repair film, but reduced the path directly from the outside to the scratched part. In addition, there was no problem with the shape such as the shape of the end of the heating roll being transferred or the repaired portion being thinned.

  An outdoor exposure test of the repaired solar cell module constructed in this way was conducted. The period is one year, and the place where the exposure was performed is located about 100 m from the coast. After the outdoor exposure period, an insulation test was conducted by a water immersion current test of the solar cell module. The applied voltage is 1000V.

  In Table 1, it has shown by (circle) noting that what was less than 1 microampere is a pass. Also, Δ is 1 μA or more and less than 100 μA, and × is 100 μA or more. The solar cell module repaired under the conditions of Experimental Example 1 passed with a current of less than 1 μA. In addition, no change in appearance, partial change in film thickness, deformation, or the like was observed, and the appearance was indicated as ◯.

  (Experimental Example 2) The scratches were repaired in the same manner as in Experimental Example 1. However, the repair film was pressure-bonded using a heating roll while heating the repaired portion to 130 ° C., which is lower than the crosslinking temperature of 150 ° C. The other conditions are the same as in Experimental Example 1. As a result, the space between the repair film and the protective film was smaller than in the case of Experimental Example 1, but the embossed shape was partially smoothed. Therefore, as shown in Table 1, the appearance is indicated by Δ. As a result of the insulation test, since the current was less than 1 μA, it passed and it was marked as ◯.

  (Experimental Example 3) The scratches were repaired in the same manner as in Experimental Example 1. However, the repaired part was crimped while degassing. The heating temperature is 60 ° C. Deaeration is performed with a vacuum pump, and air is sucked from the embossed part. The other conditions are the same as in Experimental Example 1. As a result, there was almost no space between the repair film and the protective film, and no noticeable change in appearance was seen. Therefore, the appearance is set as ◯. In addition, the result of the insulation test is a pass because the current was less than 1 μA, and it is marked as ◯.

Table 1 further lists two examples as comparative examples.
(Comparative Example 1) Here, the scratches were repaired in the same manner as in Experimental Examples 1 and 2 above. However, pressure bonding was performed with a rubber roll instead of a heating roll. That is, only pressure bonding was performed without heating. As a result, a space remained between the repair film and the protective film, and the current was 100 μA or more in the insulation test after the outdoor exposure test. Therefore, in Table 1, it is described as x. In addition, the appearance also has a problem in appearance that the reflectivity increases and looks whitish due to the space left between the repair film and the protective film.

  (Comparative Example 2) Here, as in Comparative Example 1, the wound was repaired. However, pressure bonding with a heating roll was performed at 160 ° C. higher than the crosslinking temperature of the sealing material. As a result, the space between the repair film and the protective film was small, and the current after the outdoor exposure test was 1 μA or less (circled in Table 1), but the appearance was clearly on the module after the end of the heating roll. Since it remained, it was marked with x in Table 1.

  Applicable when repairing scratches on solar cell modules.

It is a figure for demonstrating the repair method of the solar cell module of embodiment of this invention, and has shown the cross-sectional block diagram of the solar cell module. It is a top view explaining the repair method of the crack which arose in the solar cell module which embossed the light-receiving surface. It is sectional drawing in the AA line of FIG. It is a top view of the solar cell module after heat processing. It is sectional drawing in the AA line of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Solar cell module 11 Photoelectric conversion element 12, 14 Sealing material 13 Protective film 15 Reinforcement board 16 Scratch 17 Repair film

Claims (5)

In the repair method of the solar cell module in which the photoelectric conversion element is laminated with a sealing material made of at least a thermally crosslinkable first resin and a second resin having a higher melting point than the sealing material,
A repair member is provided so as to cover the scratches generated on the light receiving surface or non-light receiving surface of the solar cell module,
A repair method for a solar cell module, wherein the repair member is heated and pressure-bonded at a temperature lower than any of a crosslinking temperature of the sealing material, a melting point of the second resin, and the repair member.   The method for repairing a solar cell module according to claim 1, wherein the repair member is heated and pressure-bonded so as to fill a concave portion of an emboss structure provided on the light receiving surface.   The method for repairing a solar cell module according to claim 1, wherein the heating temperature is not higher than the melting point of the sealing material before crosslinking.   The method for repairing a solar cell module according to claim 1, wherein deaeration is performed simultaneously with the pressure bonding.   The method for repairing a solar cell module according to claim 1, wherein the repair member is an adhesive tape made of a base material and an adhesive material, and the melting point of the repair member is the melting point of the base material.

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