JP2015177169A - solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a highly reliable solar cell module by enhancing dampproofness.SOLUTION: A solar cell module has a photoelectric conversion device mounting a photoelectric conversion element on one side of a wiring sheet, and a back sheet. The back sheet is pasted to the other side of the wiring sheet, via an adhesive layer formed on the back sheet, thus providing a highly reliable solar cell module.

Description

  The present invention relates to a solar cell module.

  In recent years, the photoelectric conversion device that directly converts solar energy into electric energy has been rapidly expected as an energy source, particularly from the viewpoint of global environmental problems. Photoelectric conversion devices are often used outdoors, and are generally sealed to form a solar cell module in order to ensure strength, moisture resistance, and the like.

  FIG. 7 is a cross-sectional view showing a state in which the structural members of the back electrode type solar cell module of Patent Document 1 are stacked. FIG. 8 is a cross-sectional view showing the back electrode type solar cell module of Patent Document 1. On the transparent substrate 51, a sealing material 52a which is a first sealing material made of EVA (ethylene vinyl acetate) resin is disposed. Back electrode type solar cell string 55 is arranged on sealing material 52a so that back electrode type solar cell 53 and sealing material 52a are in contact with each other. On the back electrode type solar cell string 55, a sealing material 52b, which is a second sealing material made of EVA resin, is disposed. A back surface protection sheet 56 is disposed on the sealing material 52b.

  Next, the sealing material 52 a is pressure-bonded to the back-electrode solar cell 53 of the back-electrode solar string 55 and the sealing material 52 b is pressure-bonded to the wiring sheet 54 of the back-electrode solar string 55. By the heat treatment, the sealing material 52a and the sealing material 52b are cured in an integrated state.

  Specifically, the pressure bonding and heat treatment are performed using, for example, a laminator apparatus that can perform vacuum pressure bonding and heat treatment. By being pressurized while being heated by the laminator device, the sealing material 52a and the sealing material 52b are thermally deformed and thermally cured. The sealing material 52 a and the sealing material 52 b are integrated to form the sealing material 52, so that the back electrode type solar cell string 55 is sealed in the sealing material 52.

  As a result, as shown in FIG. 8, the back electrode type solar cell in which the back electrode type solar cell string 55 is sealed in the sealing material 52 in which the sealing material 52 a and the sealing material 52 b are integrated. The battery module 50 is produced.

JP 2012-23301 A

  The photoelectric conversion device of Patent Document 1 (in Japanese Patent Application Laid-Open Publication No. 2004-260688) is sealed with a sealing material. The EVA sheet as a sealing material has a hygroscopic property, but the front and back surfaces of the solar cell module main body are protected by the transparent substrate 51 and the back surface protection sheet 56, so that moisture does not enter. However, since the EVA sheet is exposed on the side surface of the solar cell module body, the area of the resin constituting the side surface of the solar cell module body is preferably small from the viewpoint of moisture resistance. Therefore, it was necessary to make the sealing material thinner. However, there is a limit to the thickness at which a sealing material such as EVA resin can be formed in a sheet shape, and it has been difficult to improve the moisture resistance of the side surface of the solar cell module main body by reducing the thickness of the sealing material. The present invention has been made to solve the above-described problems, and provides a highly reliable solar cell module with improved moisture resistance.

  The solar cell module of the present invention is a photoelectric conversion device in which a photoelectric conversion element is placed on one surface of a wiring sheet, and a solar cell module having a back sheet, and the back sheet is on the other surface of the wiring sheet, It is affixed via an adhesive layer formed on the backsheet.

  Moreover, the solar cell module of this invention has a transparent light-receiving surface board | substrate in the light-receiving surface side, and the peripheral part of a back sheet is adhere | attached on a transparent light-receiving surface board | substrate through the contact bonding layer.

  In the solar cell module of the present invention, the adhesive layer is an olefin-based adhesive layer.

  In the solar cell module of the present invention, the adhesive layer has a thickness of 30 μm to 100 microns.

  Further, the solar cell module of the present invention has a connection portion to the terminal box on the surface opposite to the light receiving surface, and the thickness of the solar cell module body in the connection portion is the thickness of the solar cell module body other than the connection portion. Thicker than that.

  According to the present invention, a highly reliable solar cell module with improved moisture resistance can be provided.

It is sectional drawing which shows the structure of the solar cell module which is the 1st Embodiment of this invention. It is sectional drawing which shows the solar cell module main body and solar cell module which are the 1st Embodiment of this invention. It is sectional drawing which shows the structure of the solar cell module which is the 2nd Embodiment of this invention. It is sectional drawing which shows the solar cell module main body and solar cell module which are the 2nd Embodiment of this invention. It is a top view which shows the solar cell module which is the 3rd Embodiment of this invention. It is a fragmentary sectional view which shows the solar cell module which is the 3rd Embodiment of this invention. It is sectional drawing which shows the state by which the structural member of the back surface electrode type solar cell module of a prior art example was laminated | stacked. It is sectional drawing which shows the conventional back electrode type solar cell module.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The following description is the same, and detailed description thereof will not be repeated.

(Embodiment 1)
FIG. 1 is a cross-sectional view showing the configuration of the solar cell module according to the first embodiment of the present invention. The back sheet 11 is made by laminating both surfaces of an aluminum foil with a PET resin or the like. An adhesive layer 12 is formed on the back sheet 11 by applying an adhesive of about 60 μm. As the adhesive, an olefin-based adhesive is used. Olefin-based adhesives are superior in chemical stability and moisture resistance compared to sealing materials such as EVA. In addition, epoxy-based and urethane-based resins can be used. The thickness of the adhesive layer 12 is preferably 30 μm to 100 μm.

  The photoelectric conversion device 15 is placed on the back sheet 11 on which the adhesive layer 12 is formed. The photoelectric conversion device 15 has a photoelectric conversion element 14 disposed on a wiring sheet 13. The wiring sheet 13 is for electrically connecting a plurality of photoelectric conversion elements 14 placed thereon, and is a wiring sheet in which a copper foil is patterned on a resin sheet such as PET (polyethylene terephthalate). . The photoelectric conversion element 14 is a back electrode type photoelectric conversion element in which an n electrode and a p electrode are arranged on the opposite side of the light receiving surface of the silicon substrate. The n electrode and the p electrode are electrically connected to the copper wiring of the wiring sheet 13 with solder or the like.

  A light receiving surface side sealing material 16 formed of a resin sheet such as EVA or an olefin resin is placed on the photoelectric conversion device 15. The thickness of the light-receiving surface side sealing material 16 is generally 400 μm or more. Further, a cover glass 17, which is a transparent light receiving surface substrate that forms the light receiving surface of the solar cell module, is overlaid on the light receiving surface side sealing material 16.

  FIG. 2 is a cross-sectional view showing the solar cell module body and the solar cell module according to the first embodiment of the present invention. The solar cell module main body 10 shown in FIG. 2A can be obtained by processing each component laminated as shown in FIG. 1 with a laminator.

  The light-receiving surface side sealing material 16 is bonded to the entire back surface of the cover glass 17 when heat-vacuum pressing is performed with a laminator. Moreover, it deform | transforms according to the unevenness | corrugation of the upper surface which is the light-receiving surface side of the photoelectric conversion apparatus 15, and it adhere | attaches with the upper surface and side surface of the photoelectric conversion apparatus 15 without gap.

  The light-receiving surface side sealing material 16 which is a sealing resin covering the light-receiving surface side of the photoelectric conversion device is easily deformable flexibly in the laminating process so that it can be deformed according to the unevenness on the light-receiving surface side of the photoelectric conversion device. It is preferable that the thickness is sufficient to secure the resin filled in the recess. Therefore, it is preferable to use a sealing material having a thickness of 400 μm or more as the sealing resin covering the light receiving surface side of the photoelectric conversion device.

  The back surface, which is the surface opposite to the light receiving surface of the wiring sheet 13 constituting the photoelectric conversion device 15, is bonded to the back sheet 11 via the adhesive layer 12. Since the back surface of the wiring sheet 13 is a smooth flat surface, even if the adhesive layer 12 is thin, it can be bonded to the back sheet 11 without generating a gap. Moreover, the peripheral part which is not adhere | attached on the wiring sheet 13 among the contact bonding layers 12 can seal the photoelectric conversion apparatus 15 by adhere | attaching the light-receiving surface side sealing material 16. FIG. When processed with a laminator, it is heat-pressed, but since the cover glass 17 is harder than the back sheet 11, the periphery of the back sheet is bent in the direction of the cover glass 17 and the light receiving surface side through the adhesive layer 12. The sealing material 16 is adhered.

  By setting it as the structure demonstrated above, the EVA resin exposed to the side surface of a solar cell module main body can be made thin. A highly moisture-proof solar cell module can be formed. Even if such a solar cell module main body is directly attached to the gantry, moisture resistance can be secured.

  Next, FIG. 2B shows a solar cell module 1 formed by attaching a frame 20 to the solar cell module body 10.

  The side surface of the solar cell module main body 10 comes into contact with and closely contacts a sealing resin 22 formed of butyl rubber or silicon rubber attached to the frame frame 21. Accordingly, moisture is prevented from entering the inside of the solar cell module main body 10 from the end surfaces of the light receiving surface side sealing material 16 and the adhesive layer 12. However, the sealing resin may deteriorate due to aging, and moisture may reach the end face of the solar cell module body. In such a case, since the solar cell module of this example has a thin adhesive layer 12, the area of the resin on the side surface is small compared to the structure in which the sealing material is sandwiched between the back sheet and the wiring sheet. Is less likely to enter the solar cell module body.

  In addition, it is conceivable to seal only with the sealing material disposed on the light receiving surface side of the photoelectric conversion device without forming an adhesive layer, but when the photoelectric conversion device is fixed only with the peripheral sealing material, the laminating step Therefore, there is a problem that bubbles are generated due to fine unevenness of the wiring sheet or the back sheet. By providing the adhesive layer 12 as in the present embodiment, the adhesive layer 12 absorbs fine irregularities and can adhere the back surface of the photoelectric conversion device 15, which causes a problem that bubbles are generated between the wiring sheet and the back sheet. This can improve the productivity of the solar cell module.

(Embodiment 2)
FIG. 3 is a cross-sectional view showing the configuration of the solar cell module according to the second embodiment of the present invention. The point which has apply | coated the adhesive layer 12 on the back sheet | seat 11 is the same as 1st Embodiment. Compared with the first embodiment, the light receiving surface side sealing material 16 ′ is substantially the same size as the photoelectric conversion device 15, and is different from the cover glass 17 and the back sheet 11.

  FIG. 4 is a cross-sectional view showing a solar cell module main body and a solar cell module according to the second embodiment of the present invention. The solar cell module main body shown in FIG. 4A can be obtained by processing each component laminated as shown in FIG. 3 with a laminator.

  At the end of the solar cell module body 10 ′, the back sheet 11 is bent in the direction of the cover glass 17 and bonded to the cover glass 17 via the adhesive layer 12. The light receiving surface side sealing material 16 ′ is bonded to the cover glass 17. Further, the light-receiving surface side sealing material 16 ′ is bonded to the upper surface and the side surface of the photoelectric conversion device 15 without a gap. In the present embodiment, the cover glass 17 and the back sheet 11 are in contact via the adhesive layer 12 on the side surface of the solar cell module body 10 ′. Therefore, since the sealing material is not exposed on the side surface of the solar cell module main body 10 ′, the solar cell module main body can obtain high moisture resistance.

  Furthermore, the solar cell module 1 ′ shown in FIG. 4B is formed by attaching the frame 20 to the solar cell module main body 10 ′. The side surface of the solar cell module main body 10 ′ comes into contact with and closely contacts a sealing resin 22 formed of butyl rubber or silicon rubber attached to the frame frame 21. On the side surface of the solar cell module main body 10 ′, the cover glass 17 and the back sheet 11 are in contact via the adhesive layer 12. Therefore, since the sealing material is not exposed on the side surface of the solar cell module main body 10 ′, moisture hardly enters the solar cell module main body even if the sealing resin 22 deteriorates, and the moisture resistance can be further improved. .

(Embodiment 3)
FIG. 5 is a plan view showing a solar cell module according to the third embodiment of the present invention. The figure is seen from the back side opposite to the light receiving surface side of the solar cell module, and the back sheet is omitted.

  The substantially square photoelectric conversion elements 14 are arranged vertically and horizontally on the light receiving surface side of the wiring sheet 13, and are connected to the adjacent photoelectric conversion elements by the copper wiring connection pattern of the wiring sheet 13. Further, on the side of the photoelectric conversion device 15, a bus bar in which a metal such as copper is formed in a ribbon shape is installed on the light receiving surface side of the wiring sheet 13. The bus bars 31a, 31b, 31c, 31e, and 31f rotate the connection direction of the photoelectric conversion element 14 by 180 degrees.

  The bus bar 31d is a positive side bus bar, and the bus bar 31g is a negative side bus bar. The bus bar 31d is installed on the light receiving surface side of the wiring sheet 13, and a lead wire 32a is connected thereto. Further, the bus bar 31g is installed on the light receiving surface side of the wiring sheet 13, and the lead wire 32b is connected thereto. The lead wire 32 a is guided to the back surface side of the wiring sheet 13 through the notch 33 a provided in the wiring sheet 13. Further, the lead wire 32 b is guided to the back surface side of the wiring sheet 13 through the notch 33 a provided in the wiring sheet 13.

  The resin sheet 34 formed of EVA or olefin resin is provided on the back side of the wiring sheet, and is a resin sheet having a rectangular shape of 140 mm × 110 mm and a thickness of 560 μm. A PET film 35 is disposed on the resin sheet 34. The size of the film 35 is 120 mm × 80 mm and the thickness is 500 microns. The end of the lead wire 32a is soldered to a lead wire 37a which is a terminal box connection wiring. The end of the lead wire 32b is soldered to a lead wire 37b which is a terminal box connection wiring. The lead wires 37a and 37b are connected by a tape 38 made of an insulating material such as polyimide, and the lead wires can be easily positioned in the laminating process. The lead wires 37a and 37b are drawn out from the opening of the back sheet and connected to a terminal box installed on the back surface of the solar cell module 1.

  The resin sheet 34 relaxes the effect of locally applying pressure to the photoelectric conversion element due to the level difference caused by the lead wire during the lamination process, and prevents the photoelectric conversion element from being damaged in the lamination process.

  Further, the film 35 is preferably colored in the same color as the back sheet in order to prevent the tape 38 from being seen through the gap between the photoelectric conversion elements 14 when viewed from the light receiving surface side. Further, instead of the film 35, a resin sheet colored in the same color as the back sheet may be stacked. Further, when the resin sheet 34 is colored in the same color as the back sheet, the film 35 can be omitted.

  FIG. 6 is a partial cross-sectional view showing a solar cell module according to a third embodiment of the present invention, showing a cross section taken along the line AA ′ in FIG. 5, and showing a connection portion to a terminal box. It is. The lower side is the light receiving surface side and the upper side is the back side. A photoelectric conversion device 14 is formed by placing a photoelectric conversion element 14 on the light receiving surface side of a wiring sheet 13 made of a film 13a such as PET (polyethylene terephthalate) and a wiring layer 13b. On the light receiving surface side of the photoelectric conversion device 15, a light receiving surface side sealing material 16 and a cover glass 17 are sequentially laminated.

  A resin sheet 34 and a PET resin film 35 are overlaid at a position where the terminal box on the back side of the wiring sheet 13 is arranged. Lead wires 32 a and lead wires 32 b are arranged on the film 35. Since the lead wires 37 a and 37 b are on the film 35, it is possible to prevent the lead wires from being embedded too much in the sealing material resin when processed with a laminator.

  On the back side of the wiring sheet 13, the resin sheet 34, and the film 35, the back sheet 11 on which the adhesive layer 12 is formed is attached. The back sheet 11 and the adhesive layer 12 are arranged along the shapes of the resin sheet 34 and the film 35. Further, openings 36a and 36b are formed in the back sheet 11 and the adhesive layer 12, and lead wires 37a are drawn from the back surface of the solar cell module through the openings 36a. Moreover, the lead wire 37b is drawn out from the back surface of the solar cell module through the opening 36b. Lead wires 37a and 37b drawn from the back surface of the solar cell module are connected to the terminal box, respectively.

  Thus, although the connection part 39 for the solar cell module 1 to connect to a terminal box is formed, since the resin sheet 34 is laminated | stacked, the connection part 39 of the solar cell module main body 10 is connected. It is formed thicker than other parts.

  When there is no resin sheet, the back sheet surface corresponding to the terminal box mounting part has a step due to the lead wire in the part, and bubbles may remain in the step part after the laminating process, but deformed in the laminating process Due to the resin sheet rich in properties, the step around the lead wire becomes gentle, and bubbles are less likely to remain. Also, due to the level difference due to the lead wire, the pressure to be pressed in the laminating process was concentrated on the photoelectric conversion element directly under the lead wire, and cell cracking was likely to occur. However, the resin sheet can alleviate the pressure concentration in the laminating process. Cell cracking can be prevented.

  Moreover, since thickness increases with the resin sheet 34, the mechanical strength of a terminal box attachment part can be improved.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1, 1 '... Solar cell module 10, 10' ... Solar cell module main body 11 ... Back sheet 12 ... Adhesive layer 13 ... Wiring sheet 14 ... Photoelectric conversion element 15 ... Photoelectric conversion device 16, 16 '... Light-receiving surface side sealing material 17 ... cover glass 20 ... frame 21 ... frame frame 22 ... sealing resin 31a, 31b, 31c, 31d, 31e, 31f, 31g ... bus bar 32a, 32b ... lead wires 33a, 33b ... notch 34 ... resin sheet 35 ... film 36a, 36b ... openings 37a, 37b ... connection line 38 ... tape 39 ... connection part

Claims (5)

A photoelectric conversion device having a photoelectric conversion element placed on one surface of a wiring sheet, and a solar cell module having a back sheet,
The back sheet is a solar cell module that is attached to the other surface of the wiring sheet via an adhesive layer formed on the back sheet. The solar cell module has a transparent light receiving surface substrate on the light receiving surface side,
The solar cell module according to claim 1, wherein a peripheral portion of the back sheet is bonded to the transparent light-receiving surface substrate through the adhesive layer.   The solar cell module according to claim 1, wherein the adhesive layer is an olefin-based adhesive layer.   4. The solar cell module according to claim 1, wherein the adhesive layer has a thickness of 30 μm to 100 μm. The solar cell module has a connection portion to the terminal box on the surface opposite to the light receiving surface,
The solar cell module according to any one of claims 1 to 4, wherein a thickness of the solar cell module main body in the connection portion is thicker than a thickness of the solar cell module main body other than the connection portion.