Solar Cell Module

Abstract

The purpose of the present invention is to provide a solar cell module with a superior aesthetic appearance. A solar cell module 1 according to one aspect of the present invention comprises: a plurality of solar cell strings 10 each having a plurality of solar cells 11 arranged side by side in a line and connected; a wiring member 20 which electrically connects the solar cell strings 10 and extends to the rear surface side of the solar cell strings 10; an insulating sheet 30 which is disposed between the solar cell strings 10 and the wiring member 20, and which is fixed to the plurality of solar cell strings 10; a surface protective material 50 which covers the front surface sides of the solar cell strings 10; a rear surface protective material 60 which covers the rear surface sides of the solar cell strings 10, the wiring member 20, and the insulating sheet 30; and a sealing material 70 for filling a space between the front surface protective material 50 and the rear surface protective material 60.

Description

[Technical field]

[0001] The present invention relates to a solar cell module. [Background technology]

[0002] There is known a solar cell module using a plurality of solar cell strings, each of which is formed by arranging and connecting a plurality of solar cell cells in a line. Such a solar cell module is formed by electrically connecting the plurality of solar cell strings arranged in a line with wiring members. Usually, a solar cell module is configured by arranging plate-shaped protective materials on the front and back of the plurality of solar cell strings, respectively, and filling the space around the solar cell strings between the protective materials with a sealing material, thereby preventing moisture and the like from coming into contact with the solar cell strings (for example, see Patent Document 1).

[0003] In a solar cell module, if the intervals between solar cell strings are uneven, the aesthetic appearance is impaired. When manufacturing a solar cell module, a front protective material, a first encapsulant sheet, a solar cell string, a second encapsulant sheet, and a back protective material are laminated in this order, and the encapsulant is fluidized by heat pressing to fill the spaces between the solar cell strings with the encapsulant. At this time, the position of the solar cell strings may be shifted due to the fluidization pressure of the encapsulant, which may impair the aesthetic appearance of the solar cell module. For this reason, measures such as fixing adjacent solar cell strings to each other with adhesive tape or the like are taken before heat pressing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2010-124007 A Summary of the Invention [Problem to be solved by the invention]

[0005] When solar cell strings are fixed together with adhesive tape or the like, the adhesive tape becomes visible through the gaps between the solar cell strings. It is not easy to prepare an adhesive tape (particularly an adhesive) that has a color (or a refractive index if transparent) that blends in with the sealing material or back surface protection material. In view of this situation, an object of the present invention is to provide a solar cell module that is excellent in appearance. [Means for solving the problem]

[0006] A solar cell module according to one embodiment of the present invention comprises a plurality of solar cell strings, each having a plurality of solar cells arranged and connected in a row, a wiring member electrically connecting the solar cell strings and extending to the back side of the solar cell strings, an insulating sheet disposed between the solar cell strings and the wiring member and fixed to the plurality of solar cell strings, a surface protective material covering the front side of the solar cell strings, a back protective material covering the back side of the solar cell strings, the wiring member and the insulating sheet, and a sealing material filling the space between the surface protective material and the back protective material.

[0007] The solar cell module according to one aspect of the present invention may further include an adhesive tape that fixes the insulating sheet to the solar cell string.

[0008] In the solar cell module according to the aspect of the present invention, the insulating sheet may be fixed to each of the solar cell strings by two of the adhesive tapes.

[0009] In the solar cell module according to one aspect of the present invention, the pressure-sensitive adhesive tape may have a thickness of 50 μm or more and 100 μm or less.

[0010] In the solar cell module according to one aspect of the present invention, the insulating sheet may be substantially the same color as the rear surface protection material.

[0011] In the solar cell module according to one aspect of the present invention, the insulating sheets may be disposed at both ends in an arrangement direction of the solar cells of the solar cell string.

[0012] In the solar cell module according to one aspect of the present invention, the sealing material may form a continuous layer between the solar cell string and the insulating sheet.

[0013] In the solar cell module according to one aspect of the present invention, in the solar cell string, the solar cell may be arranged such that one end of the solar cell is overlapped on the back surface side of the other end of the adjacent solar cell. Effect of the Invention

[0014] According to the present invention, it is possible to provide a solar cell module with excellent aesthetic appearance. [Brief description of the drawings]

[0015] [Figure 1] FIG. 2 is a back view showing the arrangement of components in the solar cell module according to one embodiment of the present invention. [Diagram 2] 2 is a cross-sectional view of the end portion of the solar cell module of FIG. 1 taken along line AA. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. For convenience, hatching and component symbols may be omitted. In such cases, other drawings shall be referred to. Furthermore, the dimensions of various components in the drawings have been adjusted for ease of viewing.

[0017] Fig. 1 is a rear view showing the arrangement of components in a solar cell module 1 according to one embodiment of the present invention. Fig. 2 is a cross-sectional view of an end portion of the solar cell module 1.

[0018] The solar cell module 1 comprises a plurality of solar cell strings 10, wiring members 20 that electrically connect the solar cell strings 10 and extend to the back side (the side opposite the light-receiving surface) of the solar cell strings 10, an insulating sheet 30 that is arranged between the solar cell strings 10 and the wiring members 20 and fixed to the plurality of solar cell strings 10, an adhesive tape 40 that fixes the insulating sheet 30 to the solar cell strings 10, a surface protective material 50 that covers the front side of the solar cell strings 10, a back protective material 60 that covers the back side of the solar cell strings 10, the wiring members 20 and the insulating sheet 30, and a sealing material 70 that fills the space between the surface protective material 50 and the back protective material 60.

[0019] Each solar cell string 10 has a plurality of solar cells 11 connected in a row in the direction. The solar cell string 10 has a so-called shingling structure. Specifically, in the solar cell string 10, one end of each solar cell 11 in the arrangement direction is arranged overlapping the back surface side of the other end of the adjacent solar cell 11. This prevents gaps from being created between the solar cells 11, making it possible to increase the effective area contributing to photoelectric conversion.

[0020] The solar cell 11 can be, for example, a rectangular solar cell constituted by one of the pieces obtained by dividing a large-sized semiconductor substrate of a predetermined size. The predetermined size is determined by the size of a semiconductor wafer (for example, 6 inches). For example, in the case of a 6-inch large-sized semiconductor substrate, this large-sized semiconductor substrate is divided into, for example, 2 to 10 pieces in one predetermined direction. Note that the solar cell 11 may also be a square-shaped solar cell constituted by the large-sized semiconductor substrate of the predetermined size itself.

[0021] The solar cell 11 has one or more pairs of electrodes 111 that output power. The solar cell 11 may be a double-sided electrode type in which the electrodes 111 are provided on both the front and back sides, or a back electrode type in which the electrodes 111 are provided only on the back side. In the solar cell string 10, the multiple solar cells 11 arranged in a row are electrically connected. The solar cells 11 can be connected to each other using an interconnector 12 that is a conductive connecting member, or may be connected by directly joining the electrodes 111 of adjacent solar cells 11 to each other.

[0022] The wiring members 20 are disposed at both other ends in the longitudinal direction (arrangement direction of the solar cell 11) of the solar cell string 10. The wiring members 20 can be configured to have a plurality of electrode wiring portions 21 connected to electrodes of the solar cell 11, and a transition wiring portion 22 connecting between the electrode wiring portions 21. Furthermore, the wiring member 20 on at least one side in the longitudinal direction of the solar cell string 10 further has an extraction wiring portion 23 extending from the transition wiring portion 22 to the outside of the back surface protective material 60. The wiring members 20 can be formed, for example, from a metal wire, a metal foil, or the like.

[0023] One end of the electrode wiring portion 21 is connected to the electrode 111 of the solar cell 11, and the other end is disposed on the back surface side of the insulating sheet 30. In the illustrated embodiment, the insulating sheet 30 is disposed so as to expose the electrode 111 of the solar cell 11, so that the electrode wiring portion 21 can extend linearly. However, when the insulating sheet 30 covers the electrode of the solar cell 11, the electrode wiring portion 21 may be folded back in a U-shape or a hairpin shape so as to extend from the solar cell string 10 side of the insulating sheet 30 to the back surface protective material side. Depending on the configuration of the solar cell module 1, the electrode wiring portion 21 may be integral with the interconnector 12 that connects the solar cells 11 to each other.

[0024] At least the portions of the transition wiring portion 22 and the extraction wiring portion 23 located inside the back surface protective material 60 are arranged on the back surface side of the insulating sheet 30. This prevents the wiring member 20 from coming into contact with unintended electrodes 111, etc. of the solar cell string 10, causing a short circuit. Furthermore, by arranging the transition wiring portion 22 on the back surface side of the insulating sheet 30, it is possible to make the transition wiring portion 22 invisible through gaps in the solar cell string 10 when the solar cell module 1 is viewed from the front surface side.

[0025] The insulating sheet 30 is disposed across a plurality of solar cell strings 10, preferably across all solar cell strings 10, at both ends in the arrangement direction of the solar cells 11 of the solar cell string 10, and can be configured to have a crossing portion 31 located on the front side of the jumper wiring portion 22, and an extracting wiring insulating portion 32 selectively provided in a portion where the extracting wiring portion 23 is to be disposed. In this manner, by selectively providing the insulating sheet 30 in the portion where the jumper wiring portion 22 and the extracting wiring portion 23 are to be disposed, it becomes easy to seal the solar cell string 10 with a sealant 70 described later.

[0026] The insulating sheet 30 is made of a sheet-like material having insulating properties. The insulating sheet 30 may be made of a resin such as polyethylene terephthalate (PET), acrylic resin, polyethylene (PE), olefin resin, fluorine-containing resin, or silicone-containing resin.

[0027] The insulating sheet 30 is preferably of substantially the same color as the back surface protective material 60 described below. Typically, the insulating sheet 30 can be formed from the same type of material as the back surface protective material 60. By making the insulating sheet 30 of substantially the same color as the back surface protective material 60, when the solar cell module 1 is viewed from the front side, the insulating sheet 30 exposed from the gaps in the solar cell strings 10 blends in with the back surface protective material 60, so that the insulating sheet 30 does not impair the aesthetic appearance. Note that "substantially the same color" means that the difference in hue, saturation, and brightness in the HSV color space is 10% or less, and preferably 5% or less.

[0028] The adhesive tape 40 is applied across the solar cell 11 and the insulating sheet 30, thereby fixing the insulating sheet 30 to the solar cell 11. The insulating sheet 30 is preferably fixed to each solar cell string 10 by two relatively small adhesive tapes 40. The size of the adhesive tape 40 may be, for example, 8 mm to 20 mm in width and 10 mm to 30 mm in length. By determining the relative positions of the insulating sheet 30 and the solar cell string 10 by the two adhesive tapes 40, it becomes easy to fine-tune the relative positions of the solar cell strings 10 by re-adhering the adhesive tapes 40.

[0029] The thickness of the adhesive tape 40 is preferably 50 μm or more and 100 μm or less. By using an adhesive tape of such a thickness, the relative positions of the solar cell 11 and the insulating sheet 30 can be appropriately determined without unnecessarily increasing the thickness of the solar cell module 1.

[0030] The surface protective material 50 is a layer that protects the front surface side of the solar cell string 10. The surface protective material 50 is made of a transparent, scratch-resistant material such as glass, polycarbonate, acrylic resin, etc. It is preferable that the surface protective material 50 has a sufficient thickness to provide the strength to maintain the shape of the solar cell module 1.

[0031] The surface of the surface protective material 50 may be processed to have an uneven shape, or may be coated with an anti-reflective coating layer. By using such a surface protective material 50, the surface protective material 50 is less likely to reflect incident light, so that more light can be guided to the solar cell 11, and the photoelectric conversion efficiency of the solar cell module 1 can be improved.

[0032] The back surface protective material 60 is a layer that protects the back surface side of the solar cell string 10. The material of the back surface protective material 60 is not particularly limited, but a material that can reliably prevent the intrusion of water and the like (high water impermeability) is preferable. Specifically, the back surface protective material 60 can be formed from, for example, glass, polyethylene terephthalate (PET), acrylic resin, polyethylene (PE), olefin resin, fluorine-containing resin, silicone-containing resin, or other resin. The back surface protective material 60 may also be a laminate of these materials and a material with excellent water impermeability, such as a metal foil, for example, aluminum foil.

[0033] The back surface protective material 60 preferably has a color similar to the color of the solar cell 11 when viewed from the front surface side. This makes it possible to make the gaps between the solar cell strings 10 less noticeable when the solar cell module 1 is viewed from the front surface side, thereby reducing the impact of errors in the arrangement of the solar cell strings 10 on the aesthetic appearance.

[0034] The sealing material 70 is filled in the space between the front surface protective material 50 and the back surface protective material 60 around the solar cell string 10, the wiring member 20, the insulating sheet 30, and the adhesive tape 40. The sealing material 70 suppresses deterioration of the solar cell string 10, particularly the solar cell 11, due to moisture and the like.

[0035] The sealing material 70 is formed from a material that has transparency and adhesion to the solar cell string 10, the front surface protective material 50, and the back surface protective material 60 (preferably also to the wiring member 20, the insulating sheet 30, and the adhesive tape 40). The sealing material 70 is preferably formed from a material that has thermoplasticity so that the space between these components can be filled by heat pressing. Specifically, the sealing material 70 can be formed from, for example, ethylene / vinyl acetate copolymer (EVA), ethylene / α-olefin copolymer, ethylene / vinyl acetate / triallyl isocyanurate (EVAT), polyvinyl butyrate (PVB), acrylic resin, urethane resin, silicone resin, or the like.

[0036] It is preferable that the sealing material 70 forms a continuous layer between the solar cell string 10 and the insulating sheet 30. This makes it possible to bond the solar cell string 10 and the insulating sheet 30, thereby improving the effect of sealing the solar cell string 10.

[0037] The solar cell module 1 having the above configuration can be manufactured by a manufacturing method including the steps of laminating a first sealing material sheet made of a material that forms the front portion of the sealing material 70 on top of the surface protective material 50 placed face down, arranging a plurality of solar cell strings 10 on the first sealing material sheet, connecting the plurality of solar cell strings with wiring member 20, fixing an insulating sheet 30 to the plurality of solar cell strings 10 using adhesive tape 40, laminating a second sealing material sheet and a back surface protective material 60 made of a material that forms the back portion of the sealing material 70 on top of the insulating sheet 30, and melting the first sealing material sheet and the second sealing material sheet by heat pressing to form the sealing material 70 that fills the space between the surface protective material 50 and the back surface protective material 60.

[0038] In the process of fixing the insulating sheet 30 to the solar cell strings 10 using the adhesive tape 40, the insulating sheet 30 is fixed while finely adjusting the positions of the solar cell strings 10 so that the solar cell strings 10 are arranged at equal intervals. At this time, by fixing the insulating sheet 30 to each solar cell string 10 with two adhesive tapes 40, the position and orientation of the solar cell strings 10 can be adjusted relatively easily. By fixing the insulating sheet 30 to the solar cell strings 10, the insulating sheet 30 holds the solar cell strings 10 in the subsequent process of forming the sealing material 70 by heat pressing, so that the solar cell strings 10 can be prevented from being pushed out of position by the molten sealing material forming material.

[0039] Furthermore, in the step of fixing the insulating sheet 30, a sheet of the sealant-forming material may be sandwiched between the solar cell string 10 and the insulating sheet 30. This allows a continuous layer of the sealant-forming material to be formed between the solar cell string 10 and the insulating sheet 30, thereby more reliably sealing the solar cell string 10. The sheet of the sealant-forming material sandwiched between the solar cell string 10 and the insulating sheet 30 may be smaller than the insulating sheet 30, since it may become fluid and spread in the heat pressing step.

[0040] The step of connecting the multiple solar cell strings with the wiring members 20 may be performed before the step of arranging the multiple solar cell strings 10 on the first encapsulant sheet. In other words, the multiple solar cell strings 10 may be previously connected with the wiring members and then laminated on the first encapsulant sheet.

[0041] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-mentioned embodiment, and various changes and modifications are possible. For example, in the solar cell module according to the present invention, the insulating sheet may be fixed to the solar cell string by laminating an adhesive on the surface of the insulating sheet facing the solar cell string, without using an adhesive tape. In this case, the adhesive may be partially laminated so that the adhesive is not visible through the gaps in the solar cell string. [Explanation of symbols]

[0042] 1. Solar cell module 10 Solar cell string 11 Solar Cell 12 Interconnector 21 Electrode wiring section 22 Crossover wiring section 23 Output wiring section 20 Wiring materials 30 Insulation sheet 31 Crossing Section 32 Lead wire insulation part 40 Adhesive Tape 50 Surface protection material 60 Back protection material 70 sealing material 111 Electrode

Claims

1. A plurality of solar cell strings, each of which has a plurality of solar cell cells connected in a line; a wiring member that electrically connects the solar cell strings and extends to a rear surface side of the solar cell strings; an insulating sheet disposed between the solar cell strings and the wiring member and fixed to the solar cell strings; A surface protection material for covering a front surface side of the solar cell string; a back surface protection material for covering a back surface side of the solar cell string, the wiring member, and the insulating sheet; a sealing material that fills a space between the front surface protective material and the back surface protective material; a plurality of adhesive tapes for fixing the insulating sheet to the solar cell string; Equipped with the insulating sheets are disposed at both ends of the solar cell string in an arrangement direction of the solar cell, the insulating sheet is fixed to each of the solar cell strings by two of the adhesive tapes, The width of the adhesive tape is 8 mm or more and 20 mm or less, and the length of the adhesive tape is 10 mm or more and 30 mm or less.

2. The solar cell module according to claim 1 , wherein the adhesive tape has a thickness of 50 μm or more and 100 μm or less.

3. The solar cell module according to claim 1 , wherein the insulating sheet has substantially the same color as the rear surface protection material.

4. The solar cell module according to claim 1 , wherein the sealing material forms a continuous layer between the solar cell string and the insulating sheet.

5. 5 . The solar cell module according to claim 1 , wherein in the solar cell string, one end of each of the solar cells is arranged overlapping a rear surface side of an end of the other end of the adjacent solar cell.

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