Method for manufacturing solar cell module and solar cell module

Abstract

The purpose of the present invention is to provide a solar cell module having exceptional aesthetic qualities. In the solar cell module production method according to an embodiment of the present invention, a light-receiving-surface substrate, an obverse-side sealing member layer, a solar cell string in which a plurality of solar cells are connected, a reverse-side sealing member layer, and a back sheet are laminated in the stated order, the light-receiving surface substrate being larger than the back sheet, wherein the solar cell module production method comprises: a step in which a mask is affixed to the reverse surface of the light-receiving surface substrate; a step in which a first sealing material sheet made of a first sealing material forming the obverse-side sealing member layer, the solar cell string, a second sealing material sheet made of a second sealing material forming the reverse-side sealing member layer, and the back sheet are laminated on the reverse-surface side of the light-receiving-surface substrate in the stated order; a step in which the laminate of the light-receiving surface substrate, the first sealing member sheet, the solar cell string, the second sealing member sheet, and the back sheet is hot-pressed; and a step in which the mask is removed together with the first sealing material and the second sealing material protruding on the reverse surface of the mask.

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing a solar cell module and a solar cell module. [Background technology]

[0002] A solar cell module manufacturing method is known in which a light-receiving surface substrate having translucency, a first sealing material made of a thermoplastic material, a solar cell cell connection (solar cell string), a second sealing material made of a thermoplastic material, and a backsheet are laminated in that order, and then heat pressed to obtain a solar cell module in which gaps between the light-receiving surface substrate and the solar cell string and between the solar cell string and the backsheet are filled with sealing material (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2015-56461 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the solar cell module described in Patent Document 1, the light-receiving surface substrate and the backsheet are the same size, and a frame is provided that surrounds the light-receiving surface substrate and the backsheet in a planar view, thereby confining the encapsulant between the light-receiving surface substrate and the backsheet.

[0005] Some solar cell modules have a structure in which the light-receiving surface substrate is larger than the back sheet and protrudes in a flange shape in order to be attached to the frame of the device. In such a structure, it is difficult to provide a frame that surrounds the back sheet, and the sealing material may flow out from the outer periphery of the gap between the light-receiving surface substrate and the back sheet. Increasing the amount of sealing material can prevent poor sealing of the solar cell, but the sealing material that has flowed out to the outside of the back sheet may cause inconvenience in that it mars the aesthetic appearance.

[0006] An object of the present invention is to provide a solar cell module manufacturing method capable of manufacturing a solar cell module having excellent aesthetic appeal, and to provide a solar cell module having excellent aesthetic appeal. [Means for solving the problem]

[0007] A solar cell module manufacturing method according to one embodiment of the present invention is a manufacturing method for a solar cell module in which a light-receiving surface base material, a front-side sealing material layer, a solar cell string having a plurality of solar cells connected thereto, a back-side sealing material layer, and a backsheet are laminated in this order, and the light-receiving surface base material is larger than the backsheet, the method including the steps of: attaching a mask to a back surface of the light-receiving surface base material; laminating, in this order, a first sealing material sheet made of a first sealing material that forms the front-side sealing material layer on the back surface side of the light-receiving surface base material, the solar cell string, a second sealing material sheet made of a second sealing material that forms the back-side sealing material layer, and the backsheet; heat-pressing a laminate of the light-receiving surface base material, the first sealing material sheet, the solar cell string, the second sealing material sheet, and the backsheet; and removing the mask together with the first sealing material and the second sealing material that protrude onto the back surface of the mask.

[0008] In the solar cell module manufacturing method according to one aspect of the present invention, the mask may be an adhesive tape having a resin film and an adhesive layer.

[0009] In the solar cell module manufacturing method according to one aspect of the present invention, the mask may have an opening larger than the back sheet, and the first sealing material sheet and the second sealing material sheet may have a size larger than the size of the opening.

[0010] A solar cell module according to one embodiment of the present invention comprises a light-receiving surface substrate, a front-side sealing material layer, a solar cell string having a plurality of solar cells connected thereto, a back-side sealing material layer and a backsheet, which are stacked in this order, wherein the light-receiving surface substrate is larger than the backsheet, the front-side sealing material layer and the back-side sealing material layer are joined on the outside of the solar cell string in a planar view, and the angle of the end faces of the front-side sealing material layer and the back-side sealing material layer relative to the back surface of the light-receiving surface substrate is 60° or more.

[0011] The edge surface of the backside encapsulant layer may include a ductile fracture surface.

[0012] In a solar cell module according to one embodiment of the present invention, the light-receiving surface substrate may have a light-shielding region around the entire outer edge, and end faces of the front-side sealing material layer and the back-side sealing material layer may be contained within the light-shielding region in a planar view. Effect of the Invention

[0013] According to the present invention, it is possible to provide a solar cell module manufacturing method capable of manufacturing a solar cell module having excellent aesthetic appearance, and a solar cell module having excellent aesthetic appearance. [Brief description of the drawings]

[0014] [Figure 1] FIG. 2 is a back view showing the solar cell module according to the embodiment of the present invention. [Diagram 2] 2 is a partial cross-sectional view of the solar cell module shown in FIG. 1 taken along the line AA. [Diagram 3] 2 is a photograph of the end faces of the front and back encapsulant layers of the solar cell module of FIG. 1. [Figure 4] 2 is a flowchart showing the steps of a method for manufacturing the solar cell module of FIG. [Diagram 5] 2 is a cross-sectional view showing a step of a method for manufacturing the solar cell module of FIG. 1. [Figure 6] 6 is a cross-sectional view showing a step subsequent to that of FIG. 5 in the method for manufacturing the solar cell module of FIG. [Figure 7]7 is a cross-sectional view showing a step subsequent to that of FIG. 6 in the method for manufacturing the solar cell module of FIG. [Figure 8] 8 is a cross-sectional view showing a step subsequent to that of FIG. 7 in the method for manufacturing the solar cell module of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a rear view showing a solar cell module 1 according to one embodiment of the present invention. Fig. 2 is a partial cross-sectional view of the solar cell module 1. For convenience, hatching and component symbols may be omitted, and in such cases, other drawings shall be referred to. Also, the dimensions of various components in the drawings have been adjusted for ease of viewing.

[0016] <Solar cell module> 1 includes a light-receiving surface base material 10, a front-side sealing material layer 20, a plurality of solar cell strings 30, a back-side sealing material layer 40, and a back sheet 50, which are stacked in this order from the light-receiving surface side. In the solar cell module 1, the front-side sealing material layer 20 and the back-side sealing material layer 40 fill the space between the light-receiving surface base material 10 and the back sheet 50. For this reason, the front-side sealing material layer 20 and the back-side sealing material layer 40 are joined to each other on the outer side of the solar cell string 30 in a plan view so that no void is formed around the solar cell string 30.

[0017] The light-receiving surface base material 10 is a layer that protects the front side of the solar cell string 30. The light-receiving surface base material 10 is formed from a transparent, scratch-resistant material such as glass, polycarbonate, or acrylic resin. The light-receiving surface base material 10 preferably has a sufficient thickness to provide the strength to maintain the shape of the solar cell module 1. Furthermore, by using a light-receiving surface base material 10 that has been molded into a desired shape in advance, a solar cell module 1 having a desired shape can be obtained.

[0018] The light-receiving surface base material 10 is larger than the front-side encapsulant layer 20, the plurality of solar cell strings 30, the back-side encapsulant layer 40, and the back sheet 50 in plan view. Such a light-receiving surface base material 10 functions as a flange for mounting the solar cell module 1 to a desired device. In other words, the solar cell module 1 can be mounted to a device by adhering the back surface of the outer edge portion of the light-receiving surface base material 10 to the device using an adhesive.

[0019] The light-receiving surface base material 10 has a light-shielding region 11 formed along the outer edge. The light-shielding region 11 is usually formed with a fixed width and at a fixed distance from the outer edge of the light-receiving surface base material 10. The light-shielding region 11 prevents sunlight from reaching the adhesive fixing the solar cell module 1 through the light-receiving surface base material 10 and deteriorating the adhesive when the solar cell module 1 is attached to the device. The light-shielding region 11 also improves the aesthetic appearance by covering the attachment portion of the solar cell module 1. The light-shielding region 11 can be formed, for example, by applying a black paint. A ceramic paint is generally used as the black paint.

[0020] The surface of the light-receiving surface base material 10 may be textured or may be coated with an anti-reflective coating layer. By using such a light-receiving surface base material 10, the light-receiving surface base material 10 is less likely to reflect incident light, so that more light can be guided to the solar cell string 30, improving the photoelectric conversion efficiency of the solar cell module 1.

[0021] The front-side sealing material layer 20, together with the back-side sealing material layer 40, seals the solar cell string 30, and suppresses deterioration of the solar cell string 30 due to moisture or the like. The front-side sealing material layer 20 is formed from a material (first sealing material) that has transparency and adhesion to the solar cell string 30 and the light-receiving surface base material 10. The first sealing material forming the front-side sealing material layer 20 preferably has thermoplasticity so that the gap between the solar cell string 30 and the light-receiving surface base material 10 can be sealed by heat pressing. Specifically, the first sealing material forming the front-side sealing material layer 20 can be, for example, a resin composition mainly composed of 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.

[0022] The outer edge of the front-side sealing material layer 20 is included in the light-shielding region 11 in a plan view, and is preferably located near the inner edge of the light-shielding region 11. The end face of the front-side sealing material layer 20 is inclined so as to reduce the area of ​​the front-side sealing material layer 20 toward the back side. The angle of the end face of the front-side sealing material layer 20 with respect to the back side of the light-receiving surface substrate 10 is preferably 60° or more, more preferably 75° or more. By increasing the angle of the end face of the front-side sealing material layer 20 with respect to the back side of the light-receiving surface substrate 10, it is possible to prevent the adhesion of the solar cell module 1 from being hindered when the solar cell module 1 is attached to the device even if the width of the light-shielding region 11 is reduced. The angle of the end face of the front-side sealing material layer 20 with respect to the back side of the light-receiving surface substrate 10 is determined by dividing the cross-sectional image into 10 sections in the thickness direction and averaging the angles between both ends of the end faces of each section.

[0023] The end face of the front-side sealing material layer 20 (which can be recognized as the region of the end faces of the integrated front-side sealing material layer 20 and back-side sealing material layer 40 on the light-receiving surface substrate 10 side) has a shear fracture surface at least in the region near the light-receiving surface substrate 10, as confirmed in the enlarged photograph shown in Fig. 3. By forming the region of the end face of the front-side sealing material layer 20 on the light-receiving surface substrate 10 side by shearing, the outer shape of the front-side sealing material layer 20 can be accurately formed.

[0024] Each solar cell string 30 has a plurality of solar cells 31 and a plurality of interconnectors 32 connecting adjacent solar cells 31. The multiple solar cell strings 30 are connected by wiring material 33 extending to the outside of the solar cell module 1.

[0025] There is no particular limitation on the solar cell 31, and any structure can be used for the solar cell 31. The solar cell 31 may be arranged so as not to overlap each other in a plan view, or may be arranged so that the ends overlap in a certain direction (so-called shingled arrangement).

[0026] The interconnector 32 connects between the electrodes of the solar cell 31, and electrically connects the multiple solar cell 31. In general, the multiple solar cell 31 in the solar cell string 30 are electrically connected in series. For this reason, the solar cell string 30 is connected to one solar cell 31 with one or more interconnectors 32 that connect the positive electrode of the solar cell 31 to the negative electrode of the solar cell 31 adjacent on one side, and one or more interconnectors 32 that connect the negative electrode of the solar cell 31 to the positive electrode of the solar cell 31 adjacent on the other side. When each solar cell 31 has multiple positive and negative electrodes, each interconnector 32 may also be used as a connection conductor for connecting the multiple positive or negative electrodes to collect electric charges.

[0027] The wiring members 33 electrically connect the solar cell strings 30 together, and transmit the output of the solar cell strings 30 to the outside of the solar cell module 1.

[0028] The back-side sealing material layer 40, together with the front-side sealing material layer 20, seals the solar cell string 30 and suppresses deterioration of the solar cell string 30, particularly the solar cell 31, due to moisture or the like. As the second sealing material forming the back-side sealing material layer 40, a material similar to that of the front-side sealing material layer 20 is used in order to obtain good bonding with the front-side sealing material layer 20, and preferably the same material is used.

[0029] An end face of the back-side sealing material layer 40 is continuous with an end face of the front-side sealing material layer 20. Therefore, like the end face of the front-side sealing material layer 20, the angle of the end face of the back-side sealing material layer 40 with respect to the back surface of the light-receiving surface substrate 10 is preferably 60° or more, and more preferably 75° or more.

[0030] The end face of the back-side sealing material layer 40 (which can be recognized as the region of the end face of the integrated front-side sealing material layer 20 and back-side sealing material layer 40 on the backsheet 50 side) preferably has a ductile fracture surface having an inclined striped pattern as shown in Fig. 3. By forming the region of the end face of the back-side sealing material layer 40 on the backsheet 50 side by ductile fracture, the outer edges of the front-side sealing material layer 20 and back-side sealing material layer 40 can be formed easily and inexpensively.

[0031] The back sheet 50 is a layer that protects the back side of the solar cell string 30. The material of the back sheet 50 is not particularly limited, but a material that prevents the intrusion of water and the like (high water impermeability) is preferable. Specifically, the back sheet 50 can be formed from, for example, glass, polyethylene terephthalate (PET), acrylic resin, polyethylene (PE), olefin resin, fluorine-containing resin, silicone resin, and other resins. The back sheet 50 may also be a laminate of a transparent material layer and an opaque material such as a metal foil, for example, aluminum foil. In addition, the color (light reflection characteristics) of the back sheet 50 when viewed from the front side surface is preferably similar to the color of the front side surface of the solar cell 31 in order to prevent deterioration of the aesthetic appearance of the solar cell module 1 by making it difficult to distinguish the individual solar cell 31.

[0032] It is preferable that the outer edge of the backsheet 50 is located inside the outer edge of the back-side sealing material layer 40 and is included within the light-shielding region 11 of the light-receiving surface base material 10. In this way, the backsheet 50 is present over the entire area inside the light-shielding region 11 in a plan view, thereby improving the aesthetic appearance of the solar cell module 1.

[0033] <Solar cell module manufacturing method> Next, a description will be given of a method for manufacturing the solar cell module 1 in Fig. 1. Fig. 4 is a flow chart showing the steps of the method for manufacturing the solar cell module 1. The manufacturing method shown in Fig. 4 is one embodiment of the solar cell module manufacturing method according to the present invention.

[0034] The solar cell module manufacturing method according to this embodiment includes the steps of: attaching a mask M to the back surface of the light-receiving surface base material 10 (step S1: mask attachment step); stacking, in this order, a first sealing material sheet 20S made of a first sealing material that forms the front-side sealing material layer 20 on the back surface side of the light-receiving surface base material 10, a solar cell string 30, a second sealing material sheet 40S made of a second sealing material that forms the back-side sealing material layer 40, and a back sheet 50 (step S2: lamination step); heat-pressing the laminate of the light-receiving surface base material 10, the first sealing material sheet 20S, the solar cell string 30, the second sealing material sheet 40S, and the back sheet 50 (step S3: heat-press step); and removing the mask M together with the first sealing material and the second sealing material that protrude onto the mask M (step S4: mask removal step).

[0035] In the mask attachment step of step S1, as shown in Fig. 5, a mask M having an opening A is attached to the back surface of the light-receiving surface base material 10. The inner edge of the opening A corresponds to the outer edges of the front-side sealing material layer 20 and the back-side sealing material layer 40 of the solar cell module 1 to be obtained. In addition, the opening A therefore exposes the inner edge of the light-shielding region 11 of the light-receiving surface base material 10 over the entire periphery. The size of the opening A is larger than the back sheet 50 so that the back sheet 50 can be enclosed in a plan view, and is preferably approximately equal to the size of the back sheet 50 so as to reduce the protrusion of the front-side sealing material layer 20 and the back-side sealing material layer 40 from the back sheet 50 in the solar cell module 1 to be obtained.

[0036] The mask M may be an adhesive tape having a resin film and an adhesive layer. The resin film used has a strength sufficient to shear the first sealing material and the second sealing material. Specific examples of the resin film material include polyimide and polyamide. The adhesive may be, for example, an acrylic adhesive or a silicone adhesive. The thickness of the mask M is preferably 30 μm or more and 100 μm or less. The mask M may be divided into a plurality of parts and attached. As a specific example, the opening A may be defined by attaching ribbon-shaped adhesive tapes of a certain width along each edge of the light-receiving surface base material 10.

[0037] In the lamination process of step S2, as shown in Fig. 6, a first sealing material sheet 20S, a solar cell string 30, a second sealing material sheet 40S, and a back sheet 50 are laminated in this order on the back surface side of the light-receiving surface base material 10 to which the mask M has been attached. This laminate is formed with the light-receiving surface base material 10 facing down.

[0038] The size of the first sealing material sheet 20S and the second sealing material sheet 40S is preferably larger than the opening A of the mask M so that the front-side sealing material layer 20 and the back-side sealing material layer 40 to be formed match the opening A of the mask M. Moreover, the size of the first sealing material sheet 20S and the second sealing material sheet 40S is preferably sufficiently smaller than the size of the outer edge of the mask M so as to prevent the first sealing material and the second sealing material from protruding from the outer edge of the mask M in the heat press step.

[0039] In the heat pressing process of step S3, as shown in FIG. 7, a laminate of the light receiving surface base material 10, the first sealing material sheet 20S, the solar cell string 30, the second sealing material sheet 40S, and the back sheet 50 is heat pressed. The temperature of this heat pressing is set to a temperature at which the first sealing material and the second sealing material can be softened. This heat pressing causes the first sealing material and the second sealing material to flow, so that the space around the solar cell string 30 between the light receiving surface base material 10 and the back sheet 50 is filled with the first sealing material and the second sealing material. At this time, the first sealing material and the second sealing material in the peripheral portion spread widely on the mask M, and the angle of the peripheral end faces of the front side sealing material layer 20 and the back side sealing material layer 40 formed as shown in the figure with respect to the back surface of the light receiving surface base material 10 is reduced.

[0040] 8, in the mask removal process of step S4, the mask M is peeled off from the light-receiving surface substrate 10, thereby removing the mask M together with the first sealing material and the second sealing material protruding onto the back surface of the mask M. That is, in the mask removal process, the outer edge portions of the first sealing material and the second sealing material are sheared and trimmed using the mask M to form end faces of the front-side sealing material layer 20 and the back-side sealing material layer 40. This allows the front-side sealing material layer 20 and the back-side sealing material layer 40 to have end faces that have a relatively large angle with respect to the back surface of the light-receiving surface substrate 10.

[0041] The solar cell module manufacturing method of the present embodiment can appropriately laminate front-side sealing material layer 20 and back-side sealing material layer 40 within a desired area of ​​light-receiving surface base material 10, making it possible to manufacture a solar cell module 1 that has an excellent aesthetic appearance.

[0042] 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 this embodiment, the light-receiving surface base material does not need to have a light-shielding region. In this case, too, the edges of the front-side sealing material layer 20 and the back-side sealing material layer 40 are linear, thereby improving the aesthetic appearance of the solar cell module. [Explanation of symbols]

[0043] 1. Solar cell module 10 Photosensitive surface base material 11 Shading area 20 Top side sealing material layer 20S 1st sealing material sheet 30 Solar Strings 31 Solar Cell 32 Interconnector 33 Wiring material 40 Backside encapsulant layer 40S Secondary sealing material sheet 50 Back Seat A opening M Mask

Claims

1. A method for manufacturing a solar cell module comprising: a light-receiving surface substrate; a front-side encapsulant layer; a solar cell string having a plurality of solar cells connected thereto; a rear-side encapsulant layer; and a backsheet, laminated in this order; and the light-receiving surface substrate is larger than the backsheet, the method comprising the steps of: A step of attaching a mask to a back surface of the light receiving surface base material; laminating, in this order, a first encapsulant sheet made of a first encapsulant material that forms the front-side encapsulant layer on the rear surface side of the light-receiving surface base material, the solar cell string, a second encapsulant sheet made of a second encapsulant material that forms the rear-side encapsulant layer, and the back sheet; a step of heat-pressing a laminate of the light-receiving surface base material, the first sealing material sheet, the solar cell string, the second sealing material sheet, and the back sheet; removing the mask together with the first and second sealing materials that have protruded onto a back surface of the mask; A solar cell module manufacturing method comprising:

2. 2. The method for manufacturing a solar cell module according to claim 1, wherein an adhesive tape having a resin film and an adhesive layer is used as the mask.

3. The mask has an opening larger than the backsheet, The method for manufacturing a solar cell module according to claim 1 , wherein a size of the first sealing material sheet and the second sealing material sheet is larger than a size of the opening.

4. The solar cell module includes a light-receiving substrate, a front-side encapsulant layer, a solar cell string in which a plurality of solar cells are connected, a rear-side encapsulant layer, and a back sheet, which are laminated in this order; The light receiving surface substrate is larger than the back sheet, the front-side encapsulant layer and the back-side encapsulant layer are joined to each other on the outer side of the solar cell string in a plan view; an angle of an end surface of the front-side sealing material layer and an end surface of the back-side sealing material layer with respect to a back surface of the light-receiving surface base material is 60° or more; The edge surface of the backside encapsulant layer comprises a ductile fracture surface.

5. the light-receiving surface base material has a light-shielding region around the entire periphery, The solar cell module according to claim 4 , wherein end faces of the front-side encapsulant layer and the back-side encapsulant layer are included within the light-shielding region in a plan view.

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