WO2019159729A1

WO2019159729A1 - Solar battery module

Info

Publication number: WO2019159729A1
Application number: PCT/JP2019/003789
Authority: WO
Inventors: 陽介石井; 厚志福島; 辻　雅司; 知宏吉原
Original assignee: パナソニック株式会社
Priority date: 2018-02-14
Filing date: 2019-02-04
Publication date: 2019-08-22
Also published as: JPWO2019159729A1

Abstract

A solar battery module according to one embodiment is provided with multiple solar battery cells, a curved first substrate made of resin, a curved second substrate, a sealing layer packed between the first substrate and the second substrate, and a buffer layer. The buffer layer is disposed between the first substrate and the multiple solar battery cells and has a shear modulus that is lower than that of the sealing layer. The buffer layer is formed from multiple buffer films disposed in the form of a single sheet.

Description

Solar cell module

This disclosure relates to a solar cell module.

Conventionally, a solar cell module provided with a base material that is provided on the light receiving surface side of a cell group composed of a plurality of solar cells and has a convex curved shape in a direction opposite to the cell group is known. Patent Document 1 discloses a solar cell module including a spherically curved base material. The curved solar cell module is installed in a portion of the mobile body that receives sunlight, such as the roof of an automobile.

Further, in the conventional solar cell module, a glass substrate is widely used as a substrate disposed on the light receiving surface side of the cell group. However, in order to reduce the weight of the module, a resin substrate is used instead of the glass substrate. Modules using materials are also known (see Patent Document 2). Patent Document 2 discloses providing a buffer layer made of a gel-like resin in order to relieve thermal stress and local load of the resin substrate and suppress damage to the solar battery cell.

International Publication No. 2016/031235 JP 2017-216425 A

Incidentally, a solar cell module including a resin base material and a buffer layer is manufactured by laminating (thermocompression bonding) a resin base material, a solar battery cell, a sealing layer, a buffer film constituting the buffer layer, and the like. At this time, if the resin base material is curved, it is difficult to cause the buffer film to follow the curved surface of the resin base material, and a lot of wrinkles may occur in the buffer film. The buffer layer is in close contact with, for example, the sealing layer and the resin base material, but the wrinkled portion may affect the sealing performance due to a temperature change or the like.

An object of the present disclosure is to suppress wrinkles of the buffer layer in the solar cell module including the curved resin base material and the buffer layer.

A solar battery module that is one embodiment of the present disclosure is provided with a plurality of solar cells and a first surface side of the plurality of solar cells, and has a curved shape that is convex in a direction opposite to the plurality of solar cells. A first base material made of resin, a second base material provided on the second surface side of the solar battery cell and having a curved shape convex toward the first base material, and the first base material, A sealing layer filled between the second base material, a buffer layer provided between the first base material and the plurality of solar cells, and having a shear modulus lower than that of the sealing layer; The buffer layer is composed of a plurality of buffer films arranged in a single sheet.

According to one aspect of the present disclosure, wrinkles of the buffer layer can be suppressed in the solar cell module including the curved resin base material and the buffer layer. According to the solar cell module according to the present disclosure, since the wrinkles of the buffer layer are suppressed, for example, the appearance of the module is improved and the influence on the sealing performance due to the wrinkles can be suppressed.

It is a perspective view of the solar cell module which is an example of embodiment. It is a figure which shows a part of AA line cross section in FIG. It is a figure for demonstrating the suitable length of a buffer film. It is sectional drawing of the solar cell module which is another example of embodiment. It is sectional drawing of the solar cell module which is another example of embodiment. It is sectional drawing of the solar cell module which is another example of embodiment. It is a perspective view when the solar cell module which is another example of embodiment is seen from the light-receiving side (front side). It is sectional drawing which shows a part of BB sectional drawing in FIG. 7, and is sectional drawing showing a part of YZ cross section containing a Y direction and a Z direction and passing a photovoltaic cell. It is sectional drawing which shows a part of CC sectional view taken on the line in FIG. 7, and is sectional drawing showing a part of YZ cross section which does not pass a string including a Y direction and a Z direction. It is a figure for demonstrating an example of the manufacturing method of a solar cell module. It is a figure for demonstrating the manufacturing method of the solar cell module of a 1st reference example, and is a figure for demonstrating the problem of the manufacturing method of the solar cell module of a 1st reference example. It is a figure for demonstrating another example of the manufacturing method of a solar cell module. It is a figure for demonstrating the manufacturing method of the solar cell module of a 2nd reference example, and is a figure for demonstrating the problem of the manufacturing method of the solar cell module of a 2nd reference example. It is a figure explaining application of the manufacturing method of the solar cell module shown in FIG. 12 to manufacture of the solar cell module which does not contain a film.

Hereinafter, an example of an embodiment of a solar cell module according to the present disclosure will be described in detail with reference to the drawings. Since the drawings referred to in the embodiments are schematically described, the dimensional ratios of components drawn in the drawings should be determined in consideration of the following description. In the present specification, for convenience of explanation, the terms “sheet” and “film” are used separately, but both mean a thin film-like material.

The solar cell module according to the present disclosure is preferably mounted on a moving body, for example, a vehicle such as an automobile, a bicycle (electrically assisted bicycle), a train, or a ship. Examples of vehicles include motorcycles, automobiles, electric cars, and hybrid cars. When the solar cell module is mounted on a car, an electric car, or a hybrid car, it is preferably installed on a roof, and may be installed on a sunroof.

FIG. 1 is a perspective view of a solar cell module 10 as an example of the embodiment, and FIG. 2 is a diagram showing a part of a cross section taken along line AA in FIG. As illustrated in FIGS. 1 and 2, the solar cell module 10 includes a plurality of solar cells 11, a first base material 12 provided on the first surface side of each solar cell 11, and each solar cell. And a second base material 13 provided on the second surface side of the cell 11. The first base material 12 is a resin base material having a convex curved shape in the opposite direction to the solar battery cell 11. The second base material 13 is a base material having a convex curved shape in the direction of the first base material 12, that is, in the direction of the solar battery cell 11.

In the present embodiment, the first surface of each solar cell 11 is a light receiving surface on which sunlight is mainly incident, and the second surface is a back surface (a surface opposite to the light receiving surface). Of the light incident on the solar cell 11, more than 50%, for example, 90% or more of the light is incident from the light receiving surface side. Note that the terms of the light receiving surface and the back surface are also used for the solar cell module 10 and a photoelectric conversion unit described later.

The solar cell module 10 is provided between the first base 12 and the plurality of solar cells 11, and the sealing layer 14 filled between the first base 12 and the second base 13. Buffer layer 20. The sealing layer 14 has a function of sealing the solar cell 11 so as not to be exposed to oxygen, water vapor, or the like by being in close contact with the solar cell 11 to restrain the movement of the cell. In the present embodiment, the sealing layer 14 is composed of sealing

layers

14A and 14B. The buffer layer 20 is a layer having a shear modulus lower than that of the sealing layer 14. As will be described in detail later, the buffer layer 20 is constituted by a plurality of buffer films 21 arranged in a single sheet.

The solar cell module 10 illustrated in FIG. 1 has a rectangular shape in plan view that is curved so as to be convex toward the light receiving surface, but the shape can be changed as appropriate, such as a circular shape in plan view, a polygonal shape other than a quadrangle, and the like. It may be. The solar cell module 10 includes, from the light receiving surface side, a first base material 12, a buffer layer 20, a sealing layer 14A, a plurality of solar cells 11 (in this specification, sometimes referred to as “cell group”), sealing The layer 14B and the second base material 13 have a stacked structure in which the layers are stacked in order.

The solar battery cell 11 has a photoelectric conversion unit that generates carriers by receiving sunlight, and a collecting electrode that collects carriers from the photoelectric conversion units. The photoelectric conversion unit illustrated in FIG. 1 has a substantially square shape in plan view. As an example of the photoelectric conversion portion, a semiconductor substrate such as crystalline silicon (Si), gallium arsenide (GaAs), indium phosphide (InP), an amorphous semiconductor layer formed on the semiconductor substrate, and an amorphous semiconductor And a transparent conductive layer formed on the layer. Specifically, an i-type amorphous silicon layer, a p-type amorphous silicon layer, and a transparent conductive layer are sequentially formed on one surface of an n-type single crystal silicon substrate, and an i-type amorphous material is formed on the other surface. A structure in which a silicon layer, an n-type amorphous silicon layer, and a transparent conductive layer are sequentially formed can be exemplified.

The collecting electrode includes a light receiving surface electrode formed on the light receiving surface of the photoelectric conversion unit and a back electrode formed on the back surface of the photoelectric conversion unit. In this case, one of the light-receiving surface electrode and the back electrode is an n-side electrode, and the other is a p-side electrode. In addition, the photovoltaic cell 11 may have each electrode of n side and p side only in the back surface side of a photoelectric conversion part. Generally, since the back electrode is formed in a larger area than the light receiving surface electrode, it can be said that the back surface of the solar battery cell 11 is a surface having a larger area of the collector electrode or a surface on which the collector electrode is formed. In the present embodiment, it is assumed that a light receiving surface electrode and a back surface electrode are provided as collector electrodes.

The collector electrode preferably includes a plurality of finger electrodes formed over a wide range on the photoelectric conversion unit. However, the back electrode may be an electrode that covers substantially the entire back surface of the photoelectric conversion unit. The plurality of finger electrodes are thin wire electrodes formed substantially parallel to each other. The collector electrode may include a bus bar electrode that is wider than the finger electrode and substantially orthogonal to each finger electrode.

The plurality of solar cells 11 are disposed between the base materials along the curved surfaces of the curved first base material 12 and second base material 13 and are sealed by the sealing layer 14. Adjacent solar cells 11 are connected in series by the wiring member 30, whereby a string 33 of the solar cells 11 is formed. The wiring member 30 is generally called an interconnector or a tab, and is electrically connected to the collector electrode. It is preferable that a plurality (generally, two or three) of the wiring members 30 are attached to the light receiving surface and the back surface of the solar battery cell 11. When a bus bar electrode is provided as a collector electrode, the wiring member 30 is attached along the bus bar electrode.

The wiring member 30 is provided from one side end of one solar cell 11 to the other side end of the other solar cell 11 among adjacent solar cells 11. The wiring member 30 bends in the thickness direction of the module between the adjacent solar cells 11, and a resin adhesive or solder is used for the light receiving surface of one solar cell 11 and the back surface of the other solar cell 11. Each is joined.

The solar cell module 10 preferably has a plurality of strings 33 in which a plurality of solar cells 11 are arranged in a line. On both sides of each string 33 in the longitudinal direction, wiring

members

31 and 32 are provided so as not to overlap the solar battery cells 11. The transition wiring member 31 is a wiring member that connects the strings 33 to each other. The transition wiring member 32 is a wiring member that connects the string 33 and the output wiring. A terminal box 34 incorporating a bypass diode or the like may be provided on the back side of the solar cell module 10. In this case, the output wiring member to which the crossover wiring member 32 is connected is drawn into the terminal box 34.

The solar cell module 10 may include a frame that is attached along the peripheral edges of the first base material 12 and the second base material 13. The frame protects the peripheral edge of each substrate, and may be used when the solar cell module 10 is attached to the moving body. As shown in FIG. 1, the solar cell module 10 may be a so-called frameless module having no frame.

Hereinafter, the first base material 12, the second base material 13, the sealing layer 14, and the buffer layer 20 will be described in detail.

1st base material 12 is a base material which covers the light-receiving surface of the cell group which consists of a plurality of photovoltaic cells 11, and protects each photovoltaic cell 11. The 1st base material 12 has a curved surface, and is curving so that it may become convex in the direction opposite to a cell group. For the first substrate 12, a translucent resin substrate is used. By using a resin base material for the first base material 12, the weight of the solar cell module 10 can be reduced. On the other hand, the first substrate 12 generally has a larger thermal expansion than the glass substrate, and is easily deformed when subjected to an impact. For this reason, it is preferable to provide the buffer layer 20 which relieve | moderates the load added to the photovoltaic cell 11 between the 1st base material 12 and a cell group.

Examples of the resin base material applied to the first base material 12 include acrylic resins such as polyethylene (PE), polypropylene (PP), cyclic polyolefin, polycarbonate (PC), and polymethyl methacrylate (PMMA), and polytetrafluoroethylene (PTFE). ), Polystyrene (PS), and at least one selected from polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN). An example of a suitable resin substrate is a resin substrate mainly composed of polycarbonate (PC), for example, a PC substrate having a PC content of 90% by weight or more, or 95% to 100% by weight. . Since PC is excellent in impact resistance and translucency, it is suitable as a constituent material of the first substrate 12.

The thickness of the resin base material constituting the first base material 12 is not particularly limited, but is preferably 0.001 mm to 15 mm in consideration of impact resistance (protection of the solar battery cell 11), lightness, light transmittance, and the like. 0.5 mm to 10 mm is more preferable. The resin base material is also called a resin substrate or a resin film. In general, a thick substrate is called a resin substrate, and a thin substrate is called a resin film. However, in the solar cell module 10, it is not necessary to clearly distinguish between the two. The total light transmittance of the resin substrate is preferably high, for example, 80% to 100%, or 85% to 95%. The total light transmittance is measured based on JIS K7361-1 (Plastic-Test method for total light transmittance of transparent material-Part 1: Single beam method).

The first base material 12 has a spherically curved shape and is curved in the X direction and the Y direction. Here, the X direction and the Y direction mean arbitrary directions orthogonal to each other in a plan view (two-dimensional plane) of the first base material 12 (the same applies to the second base material 13). The Z direction means a direction orthogonal to the X direction and the Y direction (XY plane). That is, the first substrate 12 has a convex curved shape in the direction opposite to the cell group in the XZ cross section and the YZ cross section. The first base material 12 has a curved surface having a three-dimensional curvature, for example, a shape obtained by cutting out a part of a spherical surface.

The curvature of the first base 12 is not particularly limited, and may be constant throughout the first base 12 or may be different in some areas. The first substrate 12 may have a flat portion in part, but preferably has a shape that is gently curved as a whole. A part of the first base 12 may have a curved portion that is convex toward the cell group. In the solar cell module 10, since the first base material 12 and the second base material 13 are curved toward the light receiving surface, the cell group, the sealing layer 14, and the buffer layer 20 sandwiched between them are also positioned on the light receiving surface side. It is curved. Note that the sealing layer 14 that is melted or softened in the laminating process easily curves following the curved surface of the substrate.

2nd base material 13 is a base material which covers the back surface of a cell group, and protects each photovoltaic cell 11. FIG. The 2nd base material 13 has a curved surface, and is curving so that it may become convex in the direction of a cell group. For the second base material 13, a translucent base material may be used similarly to the first base material 12, and an opaque base material is used when light reception from the back side of the solar cell module 10 is not assumed. May be. The total light transmittance of the second substrate 13 is not particularly limited, and may be 0%. A glass substrate or a metal substrate may be used as the second substrate 13, but in order to reduce the weight of the solar cell module 10, it is preferable to use a resin substrate.

The resin base material applied to the second base material 13 is, for example, an acrylic resin such as cyclic polyolefin, polycarbonate (PC), polymethyl methacrylate (PMMA), polyether ether ketone (PEEK), polystyrene (PS), polyethylene terephthalate ( PET), polyester such as polyethylene naphthalate (PEN), phenol resin, and at least one selected from epoxy resins.

The second base material 13 may be made of fiber reinforced plastic (FRP). In particular, FRP is preferably used in applications that require impact resistance and light weight. Suitable FRP includes glass fiber reinforced plastic (GFRP), carbon fiber reinforced plastic (CFRP), aramid fiber reinforced plastic (AFRP) and the like.

The thickness of the second substrate 13 is not particularly limited, but is preferably 0.05 mm or more. Moreover, when the 2nd base material 13 is comprised by FRP, the 2nd base material 13 has the thickness more than the thickness for one fiber. In consideration of protection of the solar battery cell 11, lightness, etc., 0.05 mm to 10 mm is preferable, and 0.05 mm to 5 mm is more preferable. The thickness of the second substrate 13 is preferably equal to or greater than the thickness of the first substrate 12.

The second base material 13 has a spherically curved shape like the first base material 12, and is curved in the X direction and the Y direction. The second base material 13 has a convex curved shape in the same direction as the first base material 12 in the XZ cross section and the YZ cross section. The 2nd base material 13 has a curved surface with a three-dimensional curvature like the shape which cut out a part of spherical surface, for example. The curvature of the second substrate 13 may be constant over the entire region or may be different in some regions, but preferably has the same curvature as that of the first substrate 12. Further, the second base material 13 may have a flat portion in part, but preferably has a shape that is gently curved as a whole.

The sealing layer 14 is provided between the 1st base material 12 and the 2nd base material 13 as above-mentioned, and forms the resin layer (sealing layer) which seals each photovoltaic cell 11. As shown in FIG. The sealing layer 14 includes a sealing layer 14A provided between the first base material 12 and the cell group, and a sealing layer 14B provided between the second base material 13 and the cell group.

The layer structure of the sealing layer 14 is preferably formed by a laminating process described later using resin films that respectively constitute the sealing layers 14A and 14B. The same resin film may be used for sealing

layer

14A, 14B, and a different resin film may be used. Examples of the resin applied to the sealing layer 14 include polyolefin, ethylene vinyl acetate copolymer, and epoxy resin. The resin may have a cross-linked structure.

The total light transmittance of the sealing layer 14A is preferably high, for example, 80% or more. On the other hand, the total light transmittance of the sealing layer 14B is not particularly limited. When light reception from the back surface side of the solar cell module 10 is not assumed, the sealing layer 14B may contain a color material such as a white pigment or a black pigment, and the total light transmittance may be 0%. .

The buffer layer 20 is a layer having a shear modulus lower than that of the sealing layer 14 as described above. The buffer layer 20 has a function of relieving a load applied to the solar battery cell 11 due to thermal expansion of the first base material 12, deformation of the first base material 12 due to a collision of falling objects, and suppressing damage to the solar battery cell 11. Have. In addition, by providing the buffer layer 20, the stress acting on the wiring material 30 can be reduced and the breakage of the wiring material 30 can be suppressed.

The shear elastic modulus of the buffer layer 20 is preferably 0.1 MPa or less, and more preferably 0.001 MPa to 0.1 MPa. If the shear modulus of the buffer layer 20 is within the range, the stress relaxation effect can be obtained while ensuring the mechanical strength, manufacturing characteristics, and the like required for the solar cell module 10. The shear modulus is measured using a rheometer.

The buffer layer 20 is provided between the first substrate 12 and the cell group so as to cover the entire cell group. The size of the buffer layer 20 is, for example, the same as the size of the first substrate 12 or slightly smaller than the first substrate 12. Although the solar cell module 10 has the structure where the 1st base material 12, the buffer layer 20, and the sealing layer 14 were laminated | stacked in order from the light-receiving surface side, arrangement | positioning of each layer is not limited to this. For example, a stacked structure in which the buffer layer 20 is sandwiched between the sealing layers 14 may be employed.

The buffer layer 20 is composed of a plurality of buffer films 21 arranged in a single sheet. That is, the buffer layer 20 is divided into a plurality. When forming a buffer layer using the buffer film of the same magnitude | size as the 1st base material 12, it is difficult to make a film follow the curved surface of the 1st base material 12, and many wrinkles generate | occur | produce in a film. In the solar cell module 10, since the buffer layer 20 is formed using a plurality of buffer films 21, the size per film is smaller than the size of the first base material 12, and the film is formed of the first base material 12. It becomes easy to follow the curved surface. For this reason, the wrinkle of the buffer film 21 can be suppressed and the beautiful buffer layer 20 which followed the curved surface of the 1st base material 12 is formed.

The buffer film 21 is preferably made of a transparent and highly flexible resin. The buffer film 21 may be composed of a gel-like resin, or may be composed of a hydrogel containing water or an organogel containing an organic solvent. The buffer film 21 is configured using at least one selected from, for example, an acrylic gel, a urethane gel, and a silicone gel. Among these, it is preferable to use a silicone gel excellent in durability.

The thickness of the buffer film 21 is not particularly limited, but is preferably 0.1 mm to 10 mm or less, more preferably 0.2 mm to 1.0 mm or less in consideration of protection of the solar battery cell 11, light transmittance, and the like. The total light transmittance of the buffer film 21 is preferably high, for example, 80% to 100%, or 85% to 95%. The plurality of buffer films 21 are generally made of the same material and have the same dimensions.

The buffer film 21 is, for example, a belt-like or strip-like film, and has a substantially constant width. The buffer layer 20 is preferably composed of 2 to 10 buffer films 21, preferably 3 to 5 buffer films 21, although it varies depending on the dimensions, curvature, etc. of the first substrate 12. It is more preferable. For example, the buffer film 21 is arranged so that the longitudinal direction thereof is along the longitudinal direction of the string 33. Each buffer film 21 has a size covering one or more rows of strings 33. In the example shown in FIG. 1, each buffer film 21 is formed in a size that covers the strings 33 for two rows.

In the present embodiment, a gap exists between the

adjacent buffer films

21A and 21B, that is, the boundary portion 22 between the two

buffer films

21A and 21B, and the sealing layer 14 is filled in the gap. The buffer film 21 may be adjacently disposed in a state in which the end portions of the film are abutted with each other so that no gap is formed in the boundary portion 22. When a gap exists in the boundary portion 22, the width of the gap is preferably 1 mm or less. The said clearance gap may exist in all the boundary parts 22 of each buffer film 21, and may exist in a part.

Moreover, the edge part of the buffer film 21 is provided in the position which overlaps the clearance gap between the photovoltaic cells 11 and the thickness direction of a module. By providing the edge part of the buffer film 21 in the position which does not overlap with the photovoltaic cell 11, the said edge part can be made not conspicuous and a favorable external appearance is obtained. Moreover, it becomes easy to conceal the end portion by providing a concealing layer 23 described later. In particular, when a gap is formed at the boundary portion 22 between the two buffer films 21, it is preferable to provide the boundary portion 22 at a position overlapping the gap between the solar cells 11. For example, all the boundary portions 22 (the gaps between the two

buffer films

21A and 21B) are provided at positions corresponding to the gaps.

FIG. 3 is a view for explaining a preferred X-direction length W ₂ of the buffer film 21. The buffer film 21 has, for example, a substantially rectangular shape in plan view, and is arranged in the X direction, which is one of the surface directions of the first base material 12. In this case, a suitable X-direction length W ₂ of the buffer film 21 is not more than the length W ₁ of the first base material 12. By adjusting the length W ₂ in the following lengths W _1, it becomes easy to suppress wrinkles of the buffer layer 20.
Here, the length W ₁ is
Arbitrary points arranged in the Y direction of the first base material 12 orthogonal to the X direction are A1, A2,
A line connecting A1 and A2 with the shortest distance along the surface of the first substrate 12 is α, and the length of the line α is L ₁ ,
The points drawn by drawing a perpendicular γ of the same length along the surface of the first base 12 from A1, A2 to the line α are B1, B2,
A line connecting B1 and B2 with the shortest distance along the surface of the first substrate 12 is β, the length of the line β is L ₂ ,
When a was a length of a perpendicular γ when the length L ₂ of the line β is equal to or more than 99.0% of the length L ₁ of the line alpha.

The solar cell module 10 having the above-described configuration can be manufactured by laminating a cell group using the first base material 12, the second base material 13, the sealing layer 14, and the plurality of buffer films 21. In the laminating apparatus, the first base material 12, the plurality of buffer films 21, the sealing layer 14A, the cell group, the sealing layer 14B, and the second base material 13 arranged in a sheet on the heater are arranged in this order. Laminated. It is preferable that sealing

layer

14A, 14B is supplied with the form of a film. This laminated body is heated to a temperature at which the resin films constituting the sealing layers 14A and 14B are softened or melted in a vacuum state, for example. Then, heating is continued while pressing each component member on the heater side under atmospheric pressure, and each member is thermocompression-bonded (laminated). In this way, the solar cell module 10 is obtained.

The plurality of buffer films 21 are arranged in a single sheet shape in a state where the respective end portions are abutted with each other or with a small gap in the boundary portion 22. At this time, it is preferable to form the laminate by disposing each buffer film 21 so that the boundary portion 22 overlaps the gap between the solar cells 11.

As described above, in the solar cell module 10, since the buffer layer 20 is formed using the plurality of buffer films 21, the size per film is smaller than the size of the first substrate 12, and each buffer It becomes easy to make the film 21 follow the curved surface of the first substrate 12. For this reason, the wrinkle of the buffer film 21 can be suppressed and the beautiful buffer layer 20 which followed the curved surface of the 1st base material 12 is formed. The solar cell module 10 has, for example, a good appearance and an excellent sealing performance.

Hereinafter, another example of the embodiment will be described with reference to FIGS. Hereinafter, the same components as those in the above-described embodiment are denoted by the same reference numerals, and redundant description is omitted.

The form illustrated in FIG. 4 is common to the form illustrated in FIG. 2 in that there is a gap at the boundary portion 22 between the

adjacent buffer films

21A and 21B, and the gap is filled with the sealing layer 14A. On the other hand, in the example shown in FIG. 4, the boundary part 22 is provided in the position which overlaps with the photovoltaic cell 11 and the thickness direction of a module. In this case, in order to make the boundary portion 22 inconspicuous, it may be provided at a position overlapping the wiring member 30. By disposing the buffer film 21 so that the wiring member 30 is located on the back side of the boundary portion 22, the boundary portion 22 is less noticeable.

The form illustrated in FIG. 5 is common to the form illustrated in FIG. 2 in that the boundary portion 22 of the

buffer films

21A and 21B is provided at a position overlapping the gap between the solar cells 11. On the other hand, in the example shown in FIG. 5, a concealing layer 23 that covers the end portion (boundary portion 22) of the buffer film 21 is provided between the first base material 12 and the buffer layer 20. The hiding layer 23 hides the boundary portion 22 so that it cannot be seen from the first base material 12 side, and improves the appearance of the module.

The concealing layer 23 is formed with an area covering the entire boundary portion 22. Moreover, it is preferable to provide the concealment layer 23 only in a range that does not overlap with the solar battery cells 11, that is, in a range that overlaps the gap between the solar battery cells 11. In this case, it is possible to prevent the light incident on the solar battery cell 11 from being blocked by the masking layer 23. The concealing layer 23 is formed, for example, in a planar view along the gap between the solar cells 11.

The masking layer 23 may be provided by arranging a film constituting the masking layer 23 between the first base material 12 and the buffer layer 20, and may be formed on the surface of the buffer layer 20 by printing or the like. Preferably, it is formed on the back surface of the first substrate 12. On the back surface of the first substrate 12, the constituent material of the concealing layer 23 may be printed, or a film constituting the concealing layer 23 may be attached. Or you may form the concealment layer 23 in the back surface of the 1st base material 12 by vapor deposition, sputtering, etc. FIG. The thickness of the masking layer 23 is not particularly limited, but an example of a suitable thickness is about 0.5 to 20 μm.

The hiding layer 23 may have a structure in which a color material is dispersed in a resin film, or a structure in which a color material is bound with a resin binder. The color (hue, color tone), visible light absorptivity, and the like of the hiding layer 23 can be adjusted by appropriately changing the type, density, layer thickness, and the like of the color material. The resin which comprises the concealment layer 23 is not specifically limited, The conventionally well-known resin binder used for printing ink can be used. The color of the masking layer 23 may be adjusted to the same color as that of the solar battery cell 11 or the second base material 13. When the masking layer 23 is black or dark blue, black pigments such as carbon black, aniline black, titanium black, and magnetite can be used as the colorant. Further, the masking layer 23 may contain a yellow pigment, a red pigment, a blue pigment, and the like.

The form illustrated in FIG. 6 is different from the form illustrated in FIG. 5 in that a barrier layer 15 is provided between the buffer layer 20 and the sealing layer 14A. Moreover, in the form illustrated in FIG. 6, the films are arranged adjacent to each other with the ends of the plurality of buffer films 21 overlapping in the thickness direction of the module. Since the end portions of the two buffer films 21 </ b> A and 21 </ b> B overlap each other, there is no gap at the boundary portion 22. In the form illustrated in FIG. 6, since the barrier layer 15 exists between the buffer layer 20 and the sealing layer 14 </ b> A, the end portions of the buffer films 21 are overlapped so that no gap is formed in the boundary portion 22. It is preferable to do.

The barrier layer 15 is a layer having an oxygen transmission rate lower than that of the first base material 12 and has a function of suppressing the oxygen passing through the first base material 12 from acting on the solar battery cell 11. The oxygen permeability of the barrier layer 15 is, for example, 200 cm ³ / m ² · 24 h · atm or less. The oxygen transmission rate is measured based on JIS K7126. The barrier layer 15 preferably has a lower water vapor transmission rate than the first base material 12. The barrier layer 15 covers the entire cell group and is provided between the first substrate 12 and the cell group.

The barrier layer 15 is composed of a plurality of barrier films 16 arranged in a single sheet. That is, the barrier layer 15 is divided into a plurality of parts, like the buffer layer 20. In this case, the wrinkles of the barrier film 16 can be suppressed, and a beautiful barrier layer 15 that follows the curved surface of the first substrate 12 is formed. The barrier layer 15 may have a seam 18 where the ends of the barrier film 16 are joined together. The joint 18 is formed by joining the overlapping end portions of two

adjacent barrier films

16A and 16B using an adhesive that develops an adhesive force in a laminating process.

The barrier film 16 may be composed of only a transparent resin film having a low oxygen permeability, and is inorganic such as a resin film and silicon oxide (silica) or aluminum oxide (alumina) formed on one surface of the resin film. You may be comprised with a compound layer. Examples of suitable resin films include fluororesin films such as polyvinyl fluoride (PVF) and ethylene-tetrafluoroethylene copolymer (ETFE), and polyester films such as polyethylene terephthalate (PET). The barrier film 16 is a PET film in which a vapor deposition layer such as silica is formed on one surface, for example.

In the form illustrated in FIG. 6, a concealing layer 23 is provided on the back surface of the first base material 12 at a position overlapping the joint 18 of the barrier layer 15 and the boundary portion 22 of the buffer layer 20 in the thickness direction of the module. For this reason, the seam 18 and the boundary part 22 are concealed, and a good module appearance is obtained.

Hereinafter, other embodiments of the solar cell module according to the present disclosure will be described in more detail with reference to FIGS. 7 to 14.

In the following description and the description of the drawings, the X direction is the arrangement direction of the plurality of strings 33 described below, and is the first curve direction that is the extending direction of the first curve that protrudes toward the light receiving side. The Y direction is the extending direction of the string 33, and is the second curved direction that is the extending direction of the second curved line that intersects the first curved line and is convex on the light receiving side. The Z direction is the thickness direction of the

solar cell modules

50, 110, and 210. The

solar cell modules

50, 110, and 210 have a curved shape. Therefore, the X direction, the Y direction, and the Z direction are determined for each point in the three-dimensional coordinates of the

solar cell modules

50, 110, and 210. For example, the X direction of each point on the surface of the solar battery cell 11 is a tangential direction parallel to the arrangement direction of the strings 33 at that point, and the Y direction is parallel to the extending direction of the string 33 at that point. It becomes the tangential direction. Also, the Z direction is the normal direction at that point. At each point of the three-dimensional coordinates on the surface of the solar battery cell 11, the X direction, the Y direction, and the Z direction are orthogonal to each other. The X direction, the Y direction, and the Z direction on the surface of the first substrate 12 and the X direction, the Y direction, and the Z direction on the back surface of the second substrate 13 are also the X direction on the surface of the solar battery cell 11, It can be determined by the same method as the determination direction of the Y direction and the Z direction. In addition, the X direction, the Y direction, and the Z direction at each point of the three-dimensional coordinates of the

solar cell modules

50, 110, and 210 other than those are viewed from, for example, the Z direction (the Z direction on the surface of the first base material 12) The X direction, the Y direction, and the Z direction can be determined to be the same as the portion of the surface of the first base material 12 that overlaps the point.

7, the solar cell module 50 illustrated in FIG. 7 has a curved shape that is convex on the light receiving side, as in the solar cell module 10, and is curved in the X direction and curved in the Y direction. The solar cell module 50 has a substantially rectangular shape in plan view. The solar cell module 50 includes a terminal box 34 on one side and the back side in the Y direction. Moreover, as shown in FIG. 8, the solar cell module 50 includes a plurality of solar cells 11, a first base material 12, a second base material 13, a wiring material 30, a sealing layer 14, a barrier film 6, and a low elastic resin. Layer 7 is provided. The same configuration as that of the above-described embodiment can be applied to the solar battery cell 11, the first base material 12, the second base material 13, the wiring member 30, and the sealing layer 14.

The barrier film 6 is disposed on the light receiving side of the sealing layer 14 and has a linear expansion coefficient smaller than that of the first substrate 12. The barrier film 6 may have any thickness. However, the barrier film 6 is preferably 110 μm or less, more preferably 30 μm or less, further preferably 25 μm or less, and most preferably 20 μm or less. On the light receiving side surface 61 of the barrier film 6, for example, a substantially circular cylindrical or frustoconical protrusion 63 in a plan view is provided so that the surface density is substantially uniform, and unevenness is provided. Also, the rear surface 62 on the back side of the barrier film 6 is provided with, for example, a substantially circular cylindrical or frustoconical protrusion 64 in a plan view so as to have a substantially uniform surface density and unevenness. However, the protrusion provided on the light-receiving side surface of the film or the back side of the back side of the film may have an elliptical shape or a polygonal shape in plan view, or any other shape in plan view. Also good. Further, when viewed from the thickness direction of the barrier film 6, the concave portion 67 of the front surface 61 of the barrier film 6 may overlap with the protruding portion 64 that is a convex portion of the rear surface 62 of the barrier film 6. The concave portion 68 of 62 may overlap the protruding portion 63 that is the convex portion of the surface 61 of the barrier film 6. The recesses 67 and 68 have, for example, a substantially circular bottomed cylindrical hole or truncated cone shape in plan view. However, the concave portions provided on the light receiving side surface of the film and the back side of the back side of the film are not limited to the shape, and may have an elliptical shape or a polygonal shape in plan view. It may have any shape, and may have any shape other than a cylinder or a truncated cone. Also, small irregularities such as undulations may exist on the outer peripheral surface and the front end surface of the protrusion provided on the light receiving side surface of the film and the back side of the back side of the film. Good. Similarly, small irregularities such as undulations may exist on the inner peripheral surface and bottom surface of the recesses provided on the light-receiving side surface of the film and the back side of the back side of the film, and there are no small irregularities such as undulations. May be. Further, the unevenness may be provided uniformly on the surface on the light receiving side of the film, or may be provided randomly. Further, the unevenness may be provided uniformly on the back side of the back side of the film, or may be provided randomly. The barrier film 6 is formed, for example, by embossing a flat film base material having a constant thickness, and is formed by partially lifting and floating the back surface of the film base material. 9 is a cross-sectional view showing a part of the CC line cross-sectional view of FIG. 7, and includes a Y-direction and a Z-direction, and represents a part of the YZ cross-section that does not pass through both the solar battery 11 and the wiring member 30. FIG. As shown in FIG. 9, the barrier film 6 has irregularities in a portion that does not overlap both the solar battery cell 11 and the wiring member 30 when viewed from the thickness direction of the barrier film 6. That is, the unevenness of the barrier film 6 is provided, for example, at a position corresponding to a gap between adjacent strings 33 (a portion overlapping the gap and the thickness direction of the module). It is preferable that the barrier film 6 has unevenness in a portion between two adjacent strings 33 in the first curve direction.

As the material of the barrier film 6, for example, the same material as the material of the existing gas barrier film that suppresses the passage of oxygen and water vapor can be adopted. The barrier film 6 may be composed of the same film as the barrier film 16. The film may include, for example, a base film and a barrier laminate formed on the base film, and is formed by alternately providing an organic layer and an inorganic barrier layer on the base film. May be. For example, you may provide an organic layer, an inorganic barrier layer, an organic layer, and an inorganic barrier layer in that order so that each surface may mutually adjoin on one side of a base film. In the film, the barrier laminate may be provided only on one side of the base film, or may be provided on both sides. Moreover, a barriering laminated body may be comprised by laminating | stacking in order of an inorganic barrier layer and an organic layer from the base film side, and may be comprised by laminating | stacking in order of an organic layer and an inorganic barrier layer. A film may have structural components (for example, functional layers, such as an easily bonding layer) other than a barriering laminated body and a base film. The functional layer may be disposed on the barrier laminate, between the barrier laminate and the base film, or on the side where the barrier laminate on the base film is not installed.

It is preferable to use a plastic film as the base film. The plastic film is not particularly limited in material, thickness and the like as long as it can hold a laminate such as an organic layer and an inorganic barrier layer, and can be appropriately selected according to the purpose of use. Specific examples of the resin constituting the plastic film include polyester resin, methacrylic resin, methacrylic acid-maleic acid copolymer, polystyrene resin, transparent fluororesin, polyimide, fluorinated polyimide resin, polyamide resin, polyamideimide resin, Polyetherimide resin, cellulose acylate resin, polyurethane resin, polyetheretherketone resin, polycarbonate resin, alicyclic polyolefin resin, polyarylate resin, polyethersulfone resin, polysulfone resin, cycloolefin copolymer, fluorene ring modified polycarbonate resin And thermoplastic resins such as an alicyclic modified polycarbonate resin, a fluorene ring modified polyester resin, and an acryloyl compound.

The low elastic resin layer 7 is disposed between the first base material 12 and the barrier film 6. The low elastic resin layer 7 preferably has a lower tensile elastic modulus than the first base material 12, and has a lower tensile elastic modulus than any of the first base material 12, the second base material 13, and the sealing layer 14. If present, it is more preferable. The low elastic resin layer 7 is most preferable if it has a lower tensile elastic modulus than any of the first base material 12, the second base material 13, the sealing layer 14, and the barrier film 6. However, the low elastic resin layer 7 may have the same tensile elastic modulus as that of the first base 12, and may have a higher tensile elastic modulus than the first base 12. The low elastic resin layer 7 is preferably made of a gel-like translucent resin material (hereinafter simply referred to as gel), and the gel may or may not contain a solvent. Examples of the gel containing a solvent include a hydrogel in which the dispersion medium is a water gel and an organogel in which the dispersion medium is an organic solvent gel. Examples of the gel containing the solvent include a polymer gel having a number average molecular weight of 10,000 or more, an oligomer gel having a number average molecular weight of 1,000 or more and less than 10,000, or a low molecular gel having a number average molecular weight of less than 1,000. The low elastic resin layer 7 may be made of the same material as that of the buffer layer 20.

However, it is preferable to use a polymer gel containing a solvent or a gel not containing a solvent because the movement of the plurality of solar cells 11 can be suppressed, and damage to the wiring member 30 due to the movement can be suppressed. Moreover, it is preferable to contain at least one selected from the group consisting of a silicone gel, an acrylic gel, and a urethane gel among polymer gels containing a solvent or gels containing no solvent. These gels have a small tensile elastic modulus and are easy to relieve the thermal stress and local load of the first substrate 12 due to temperature changes. Therefore, damage to the wiring member 30 can be effectively suppressed. In addition, the silicone gel has flexibility that can mitigate external impacts, and it is easy to improve adhesion to the resin material constituting the substrate material or the frame body, and is excellent in moisture resistance, water resistance, and the like. Therefore, the low elastic resin layer 7 is most preferably composed of silicone gel.

The tensile elastic modulus of the low elastic resin layer 7 is not particularly limited, but is preferably 0.1 kPa or more and less than 5 MPa, and more preferably 1 kPa or more and 1 MPa or less. By setting the lower limit of the tensile elastic modulus of the low elastic resin layer 7 to such a value, the solar battery cell 11 can be easily fixed, and damage to the wiring member 30 due to the movement of the solar battery cell 11 can be suppressed. Moreover, the thermal stress and local load of the 1st base material 12 by a temperature change can be relieve | moderated efficiently by making the upper limit of the tensile elasticity modulus of the low elastic resin layer 7 into such a value.

The first base material 12, the low elastic resin layer 7, the barrier film 6, the sealing layer 14, the solar cell 11 and the wiring material 30, and the second base material 13 are, for example, at a temperature of about 100 to 160 ° C. under high vacuum. Bonded and integrated by vacuum laminating performed in FIG. 10 is a diagram illustrating a method for manufacturing the solar cell module 50. Hereinafter, an outline of the vacuum laminating process will be described with reference to FIG.

When performing vacuum laminating, first, the curved front side base material 19 that is the base material of the first base material 12 and the base material of the second base material 13 that substantially correspond to the curved shape of the product. A back-side base material 25 having a curved shape is prepared. The rigidity of the front side base material 19 is smaller than or substantially the same as the rigidity of the back side base material 25. Further, each of the front side and back

side base substrates

19 and 25 has a curved shape in which the front side is convex on the light receiving side, and the curvature radius of the back side of the front side base substrate 19 is the surface 26 of the back side base substrate 25. It is preferable that it is larger than the curvature radius. However, each of the front-side and back-

side base materials

19 and 25 may have a curved shape that is convex to the light-receiving side as a whole, a part may be a flat plate shape, and a part is a concave shape to the light-receiving side. It may be. Moreover, it is preferable that the thickness of the front side base material 19 is thinner at the center than at the periphery. Each of the front side base material 19 and the back side base material 25 is formed by, for example, injection molding.

Next, for example, the back side base material 25, the back side sheet material 41 constituting the back side portion of the sealing layer 14 with respect to the solar cells 11, the solar cells 11 and the wiring material 30 (not shown in FIG. 10), sealing A front side sheet material 42 constituting a front side portion of the stop layer 14 with respect to the solar battery cell 11, a film base material 43 that is a base material of the barrier film 6, a low elastic resin base material 45 that is a base material of the low elastic resin layer 7, and A laminated structure in which the front base material 19 is laminated in this order is disposed between a pair of silicone rubbers (diaphragms) of a vacuum laminating apparatus. As shown in the lower diagram of FIG. 10, that is, an enlarged view of a part of the film base material 43, each of the front and back surfaces of the film base material 43 has irregularities formed by embossing or the like.

Subsequently, one or both silicone rubbers are inflated with compressed air while evacuating air between the laminated structures to the outside by evacuation, and the front side base substrate 19 is moved to the back side base substrate 25 until it cannot move. The laminated structure is pressed in the thickness direction. In this process, as shown by an arrow C in FIG. 10, the film base material 43 is deformed from a flat shape to a curved shape. In addition to the evacuation and pressurization, the laminated structure is heated at a temperature of about 100 to 160 ° C. with a heater of a vacuum laminating apparatus.

The pressure at this high temperature causes the back side of the front side base material 19, which has lower rigidity than the back side base material 25, to bend into a shape corresponding to the surface 26 of the back side base material 25. Then, the front base material 19 and the low elastic resin base material 45 are brought into contact with no gap, and the low elastic resin base material 45 and the film base material 43 are brought into contact with no gap. Further, the front sheet material 42 and the back sheet material 41 are fused so as to seal the solar cells 11 and the wiring material 30 (not shown in FIG. 10), and the front sheet material 42 and the film base material 43 are bonded together. Glue. Further, the back side sheet material 41 and the back side base material 25 are bonded. By such fusion or the like, the front side base substrate 19 and the back side base substrate 25 are bonded together, and the laminated structure is integrated in a shape corresponding to the product. In this way, the first base material 12 is formed from the front side base material 19 and the second base material 13 is formed from the back side base material 25. Finally, for example, a frame is attached to the periphery of the laminated structure to prevent the gel-like low-elasticity resin layer 7 from flowing to the outside, and the solar cell module 50 is formed.

In addition, the case where an unevenness | corrugation was formed in the barrier film 6 by previously forming an unevenness | corrugation in the film base material 43 which is the original material of the barrier film 6 by embossing etc. was demonstrated. However, irregularities may be formed on the film by forming irregularities on the film base material, which is the original material of the film, at the time of lamination. Further, the curvature radius of the back surface of the front-side base material 19 is larger than the curvature radius of the surface 26 of the back-side base material 25, and the rigidity of the front-side base material 19 is smaller than or substantially the same as the rigidity of the back-side base material 25. Explained the case. The case where the back surface of the front side base material 19 is deformed so as to be along the surface 26 of the back side base material 25 has been described. However, the back surface of the front side base material may be a flat surface, and the surface of the back side base material may be a curved surface. And you may curve the back surface of a front side base material so that the surface of a back side base material may be met. Also, the rigidity of the front side base material is substantially the same as or larger than that of the back side base material, and the curvature radius of the back side of the front side base material is smaller than the curvature radius of the surface of the back side base material. Also good. Or, the rigidity of the front side base material is substantially the same or larger than that of the back side base material, and the back side of the front side base material is a curved surface, while the surface of the back side base material is flat. May be. And you may deform | transform the surface of a back side base material so that the back surface of a side base material may be followed.

Further, the case where the thickness of the front side base material 19 is thinner at the center than at the periphery has been described. However, the thickness of the front base material to be deformed may be substantially constant. Further, the case where a pair of silicone rubbers is inflated with compressed air and the laminated structure is pressurized in the thickness direction by vacuum lamination has been described. However, the laminated structure disposed between the pair of rubber plates may be compressed by moving the pair of rubber plates so that the distance between the pair of rubber plates is reduced by pressure using hydraulic pressure or the like. Moreover, the case where the solar cell module was provided with the frame (frame) was demonstrated. However, for example, in one of the front-side base substrate and the back-side base substrate, a portion to be a side portion of the solar cell module is provided, and after the vacuum laminating process, the low-elasticity resin layer is formed on this side portion. It may be sealed to prevent the flow of the low elastic resin layer to the outside. Or you may adhere | attach the 1st base material and the 2nd base material in the edge part of a solar cell module so that it may become thin as the thickness of a solar cell module goes to a peripheral part from a center part. By adopting these structures, the solar cell module may not have a frame.

Referring to FIG. 7 again, the plurality of solar battery cells 11 are arranged in a matrix in the solar battery module 50. Two or more solar cells 11 arranged on the same straight line along the Y direction are connected in series by the wiring member 30. The two or more solar cells 11 and the wiring member 30 connecting the two or more solar cells 11 in series constitute a string 33.

In the example shown in FIG. 7, in two strings 33 adjacent to each other in the X direction, the solar cells 11 at one end in the Y direction are connected in series by a relay wiring, and all the solar cells 11 are connected in series. . As a result, the solar cell 11A disposed on the most terminal side in the Y direction and on the rightmost side in the drawing is arranged on the highest potential side, and arranged on the most terminal side in the Y direction and on the leftmost side in the drawing. The provided solar battery cell 11B is disposed on the lowest potential side. Unlike the present embodiment, the solar cell disposed on the most terminal box side in the Y direction and on the rightmost side on the paper surface is disposed on the lowest potential side, and the solar cell disposed on the most terminal box side on the paper surface in the Y direction. The solar battery cell disposed on the left side may be disposed on the highest potential side.

The solar cell module 50 includes four

output wirings

32A, 32B, 32C and 32D for electrically connecting to the terminals of the terminal box 34 on the terminal box 34 side in the Y direction. The outer peripheral surface of each

output wiring

32A, 32B, 32C, 32D is covered with an insulating member such as an insulating film. Of the four

output wirings

32A, 32B, 32C, 32D, the two

output wirings

32B, 32C also have a function of connecting two adjacent strings 33 in series. The output wiring 32A is disposed on the rightmost side in the X direction and is electrically connected to the high potential side of the string 33 on the highest potential side. The output wiring 32B is arranged in the second column from the right in the X direction, and is arranged in the third column from the right in the X direction with the solar cell 11 on the lowest potential side of the second highest potential string 33. The third solar cell 11 on the highest potential side of the third highest potential string 33 is electrically connected. The output wiring 32C is arranged in the fourth column from the right in the X direction and is arranged in the fifth column from the right in the X direction with the solar cell 11 on the lowest potential side of the fourth highest potential string 33. The solar cell 11 on the highest potential side of the fifth highest potential string 33 is electrically connected. The output wiring 32D is arranged in the sixth column from the right in the X direction and is electrically connected to the lowest potential side of the string 33 having the lowest potential.

The second base material 13 has a plurality of through holes (not shown). Each

output wiring

32A, 32B, 32C, 32D is electrically connected to a predetermined terminal of the terminal box 34 after passing through one of the through holes. Although not described in detail, a bypass diode for preventing backflow is provided between the terminals in the terminal box 34. If a light-shielding object such as fallen leaves covers a specific solar cell 11, the amount of power generated by the solar cell 11 may decrease and heat may be generated. The two strings 33 connected in series including the solar battery cells 11 whose power generation amount is reduced by providing the bypass diode are substantially short-circuited by the bypass diode. As a result, no current substantially flows through the two strings 33, and damage to the solar battery cell 11 due to heat generation is suppressed. The electric power from the solar cell module 50 is taken out by two electric power supply wirings (not shown) electrically connected to the terminals of the terminal box 34. In the example illustrated in FIG. 7, the solar cell module 50 includes the strings 33 arranged in six rows, but the solar cell module may include strings arranged in a plurality of rows other than the six rows.

As described above, the solar cell module 50 is a solar cell module having a convex curved shape on the light receiving side where light mainly enters. In addition, the solar cell module 50 includes a plurality of strings 33 arranged at intervals in a first curve direction (X direction) that is an extending direction of the first curve that protrudes toward the light receiving side. Each string 33 intersects the first curve and is arranged at intervals in the second curve direction (Y direction) that is the extending direction of the second curve that is convex on the light receiving side. , And a plurality of wiring members 30 that electrically connect the plurality of solar cells 11. In addition, the solar cell module 50 includes a first base material 12 that is provided on the light receiving side with respect to the string 33, has a convex curved shape on the light receiving side, and is made of a translucent resin material. The solar cell module 50 is provided on the back side opposite to the light receiving side with respect to the string 33, and seals the second base material 13 having a convex curved shape on the light receiving side and the plurality of strings 33. The sealing layer 14 arrange | positioned in is provided. The solar cell module 50 includes a barrier film 6 disposed on the light receiving side of the sealing layer 14 and a low-elasticity resin layer (filler layer) 7 disposed between the first substrate 12 and the barrier film 6. Is provided. The barrier film 6 has a linear expansion coefficient smaller than that of the first substrate 12. Further, as described with reference to FIG. 9, the barrier film 6 has irregularities in a portion that does not overlap both the solar battery cell 11 and the wiring member 30 when viewed from the thickness direction of the barrier film 6. Here, the two or more solar cells 11 arranged on the same straight line along the Y direction and the wiring member 30 connecting the two or more solar cells 11 in series constitute a string 33. Therefore, the barrier film 6 has unevenness in a portion between two strings 33 adjacent in the X direction.

According to the above configuration, the barrier film 6 has unevenness, and the film base material 43 which is the original material of the barrier film 6 has unevenness. Therefore, the film base material 43 is less likely to be wrinkled at the time of lamination, and as a result, the barrier film 6 in the finished product is also less likely to be wrinkled. As a result, the solar cell module 50 has a good appearance and hardly peels off. Can be manufactured. Next, this will be described by comparing with the solar cell module 310 of the reference example. FIG. 11 is a diagram corresponding to FIG. 10 in the solar cell module 310 of the first reference example, and is a diagram illustrating a problem when a flat film base material 343 having no irregularities is used. In FIG. 11, the same components as those in FIG. 10 are denoted by the same reference numerals as those in FIG.

Referring to FIG. 11, when a flat film base material 343 is used as a film base material, the film base material 343 has a shape that hardly absorbs unevenness. Therefore, when the film base material 343 is bent during the lamination process indicated by the arrow D, the film base material 343 contracts the front side sheet material 42 due to the unevenness generated on the surface of the front side sheet material 42 as the front side sheet material 42 contracts. It becomes difficult to follow smoothly. Therefore, wrinkles (not so much) 380 are easily formed on the film base material 343, and the wrinkles 380 deteriorate the appearance of the solar cell module. Further, the wrinkles 380 can be a starting point of peeling, can also be a moisture intrusion path, and can be a hotbed for deterioration. Depending on the specifications, a thin film may be desired, and a film having a thickness of 25 μm or less or a film having a thickness of 20 μm or less may be desired. However, in such a case, since the rigidity of the film is small and the film becomes weak, the film is less likely to follow the shrinkage of the front side sheet material, and there is a high risk of wrinkling.

On the other hand, in the case of this embodiment shown in FIG. 10, the barrier film 6 has irregularities, and the film base material 43 that is the base material of the barrier film 6 has irregularities. Therefore, the film base material 43 is caused by the irregularities. It has spring properties. Therefore, the unevenness of the front side sheet material 42 that occurs as the front side sheet material 42 contracts can be absorbed by its spring property, and the force applied from the front side sheet material 42 by the spring property of the film base material 43 is applied to the film base material 43. It becomes easy to disperse globally and uniformly. Therefore, the film base material 43 is easily shrunk uniformly during the laminating process, and wrinkles are hardly generated in the film base material 43. As a result, it is possible to make the solar cell module 50 look good and hardly peel and deteriorate.

Further, the filler layer provided between the first base material 12 and the barrier film 6 may be the low elastic resin layer 7 having a lower tensile elastic modulus than the first base material 12.

According to this configuration, the low elastic resin layer 7 having a low tensile elastic modulus is provided between the first substrate 12 and the barrier film 6. Therefore, even if the first base 12 is a resin base having a high linear expansion coefficient, the low elastic resin layer 7 can alleviate the influence of heat shrinkage of the first base 12. Therefore, the influence of the thermal contraction of the first base material 12 becomes difficult to be transmitted to the wiring member 30, and damage to the wiring member 30 can be suppressed.

Further, the unevenness may be provided on both the light receiving side surface 61 of the barrier film 6 and the back surface 62 on the back side of the barrier film 6. Further, when viewed from the thickness direction of the barrier film 6, the concave portion 67 of the front surface 61 of the barrier film 6 overlaps the protruding portion (convex portion) 64 of the rear surface 62 of the barrier film 6, and the concave portion of the rear surface 62 of the barrier film 6. 68 may overlap the protruding portion (convex portion) 63 of the surface 61 of the barrier film 6.

According to this configuration, a portion having a large thickness and high rigidity and a portion having a small thickness and low rigidity are less likely to be unbalanced in the barrier film 6. Therefore, the spring property of the barrier film 6 can be increased, and the effect of suppressing the generation of wrinkles can be increased.

Further, the thickness of the barrier film 6 may be 110 μm or less.

As described above, when the thickness of the barrier film 6 is 110 μm or less, the rigidity of the barrier film 6 is reduced, and the barrier film 6 is more easily wrinkled. When the thickness of the barrier film 6 is 25 μm or less, The barrier film 6 is more easily wrinkled. Therefore, when the thickness of the barrier film 6 is 110 μm or less, the effect of suppressing generation of wrinkles in the barrier film 6 can be increased by providing the barrier film 6 with irregularities. Moreover, when the thickness of the barrier film 6 is 25 μm or less, the effect of suppressing the generation of wrinkles in the barrier film 6 can be made remarkable by providing the barrier film 6 with irregularities.

Further, the irregularities may be formed on the barrier film 6 by embossing.

According to this configuration, irregularities can be easily and inexpensively formed on the barrier film 6.

In addition, this indication is not limited to the said embodiment and its modification, A various improvement and change are possible in the matter described in the claim of this application, and its equivalent range.

For example, in the above embodiment, the case where the first base material 12 to the second base material 13 are integrated at a time by the vacuum laminating process and the solar cell module 50 is formed by integral molding has been described. However, as shown in FIG. 12, that is, a diagram illustrating a method for manufacturing the solar cell module 110, the solar cell module 110 may be formed by separation molding described below.

In detail, the back side base material 25 which is a base material of the 2nd base material 103, the back side sheet material 41 which comprises the back side part with respect to the photovoltaic cell 11 in the sealing layer 105, the photovoltaic cell 11, and a wiring material (in FIG. 12). The laminated structure 180 in which the front side sheet material 42 constituting the front side portion of the sealing layer 105 with respect to the solar battery cell 11 and the film base material 43 provided with the unevenness is laminated in this order is used as a pair of vacuum laminating apparatuses. After being disposed between the silicone rubbers (diaphragms), vacuum lamination may be performed at a high temperature to form an integrated laminated structure 190 that does not include the first substrate 102. Then, the solar cell module 110 is formed by pasting the first base material 102 to the film 106 side in the thickness direction of the laminated structure 190 via the gel-like low elastic resin layer 107 at room temperature. May be. Moreover, you may bond at about 130 degreeC. Thereby, the adhesive force of the 1st base material 102 and the low elastic resin layer 107 and the low elastic resin layer 107 and the film base material 43 improves.

In more detail, the manufacturing method of the solar cell module 110 includes a plurality of solar cells 11, a first base material 102 disposed on a light receiving side on which light mainly enters the plurality of solar cells 11, a plurality of suns. Even if it is the manufacturing method of a solar cell module provided with the 2nd base material 103 provided in the back side on the opposite side to the light reception side with respect to the battery cell 11, and the sealing layer 105 which seals the several photovoltaic cell 11. FIG. Good. Moreover, in the manufacturing method of the solar cell module 110, the front side sheet | seat material (light reception side sheet | seat material) 42 which is the original material of the light reception side sealing layer located in the light reception side rather than the photovoltaic cell 11 in the sealing layer 105, a plurality of In the solar cell 11, the sealing layer 105, the back side sheet material 41 that is the base material of the back side sealing layer located on the back side of the solar cell 11, and the back side base material 25 that is the base material of the second base material 103. May be laminated in this order. Then, the front side sheet material 42 and the back side sheet material 41 are melted, and the front side sheet material 42 and the back side sheet material 41 are fused while sandwiching the plurality of solar cells 11, and the back side sheet material 41 and the back side A laminated structure 190 in which the plurality of solar cells 11, the sealing layer 105, and the second base material 103 are integrated may be formed by bonding the original base material 25. And after that, the first base material 102 may be bonded to the opposite side to the second base material 103 in the thickness direction of the laminated structure 190 via an adhesive material. Further, the solar cell module 110 may include a film 106 between the first base material 102 and the sealing layer 105. And after arrange | positioning the film base material 43 which is the base material of the film 106 on the opposite side to the photovoltaic cell 11 of the front side sheet material 42, you may fuse the front side sheet material 42 and the back side sheet material 41. FIG. In this manner, a laminated structure 190 including the film 106 on the opposite side of the sealing layer 105 from the second base material 103 may be formed. In addition, the film 106 of the solar cell module 110 may have a lower tensile elastic modulus than the first base material 102. Moreover, the film base material 43 may have unevenness.

Next, the superiority of the manufacturing method of the solar cell module 110 of the modification will be described by comparing with the manufacturing method of the solar cell module 410 of the second reference example. FIG. 13 is a diagram illustrating a method for manufacturing the solar cell module 410 of the second reference example. As shown in FIG. 13, when the front side base substrate 415 to the back side base substrate 425 are integrated at a time by high temperature laminating, the first base material is affected by the deformation of the back side layer during laminating. 402 may be deformed such that its surface 420 undulates. In particular, when the sealing layer is made of a resin material in which polymers are linked by crosslinking, the crosslinking temperature of the sealing resin is likely to be higher than the heat resistance temperature of the front side base material 415. Therefore, the first base material 402 is easily affected by heat at the time of laminating, and the surface 420 of the first base material 402 is easily deformed so as to wave.

On the other hand, in the method for manufacturing the solar cell module 110 shown in FIG. 12, the first base material 102 is laminated to the laminated structure 190 through the low-elasticity resin layer 107 at room temperature, so the first base material 102 is laminated. Not affected by processing. Therefore, it can suppress or prevent that the 1st base material 102 deform | transforms so that the surface may wave.

In addition, it cannot be overemphasized that the manufacturing method of the solar cell module 110 demonstrated using FIG. 12 can be applied to the manufacturing method of the solar cell module containing the film which does not have an unevenness | corrugation. Moreover, the manufacturing method of the solar cell module 110 demonstrated using FIG. 12 is applicable also to the manufacturing method of the solar cell module 210 which does not contain a film.

FIG. 14 is a diagram for explaining the application of the method for manufacturing the solar cell module 110 shown in FIG. 12 to the manufacture of the solar cell module 210 that does not include a film.

As shown in FIG. 14, in this manufacturing method, the back side base material 225 which is a base material of the 2nd base material 203, the back side sheet material 241 which comprises the back side part with respect to the photovoltaic cell 11 in the sealing layer 205, a solar cell Cell 11 and wiring material (not shown in FIG. 14), front-side sheet material (light-receiving-side sheet material) 242 constituting the front-side portion of the sealing layer 205 with respect to the solar battery cell 11, and a sheet member having a coating that does not adhere to the outer surface The laminated structure 280 obtained by laminating 249 in this order is disposed between a pair of silicone rubbers (diaphragms) of a vacuum laminating apparatus, and then vacuum lamination is performed at a high temperature, so that the first substrate 202 is not included. A stacked structure 290 is formed. Then, after the sheet member 249 is peeled off, the first base material 202 is placed on the side opposite to the second base material 203 side in the thickness direction of the laminated structure 290 at a normal temperature and a gel-like low elastic resin layer 207. The solar cell module 210 is formed by pasting together.

According to the manufacturing method of this modification, the front side sheet material 242 and the back side sheet material 241 are placed in a state where the sheet member 249 is arranged on the opposite side of the front side sheet material (light receiving side sheet material) 242 from the solar battery cell 11 side. Melt. Therefore, the sheet member 249 can suppress or prevent the surface of the front sheet material 242 from undulating due to laminating. Therefore, similarly to the method shown in FIG. 12, the first base material 202 is not affected by the laminating process performed at high temperature and high pressure, and the deformation of the surface of the first base material 202 can be suppressed or prevented. .

10 solar cell module, 11 solar cell, 12 first base material, 13 second base material, 14, 14A, 14B sealing layer, 15 barrier layer, 16, 16A, 16B barrier film, 18 joint, 20 buffer layer, 21, 21A, 21B Buffer film, 22 boundary, 23 concealment layer, 30 wiring material, 31, 32 transition wiring material, 33 string, 34 terminal box

Claims

A plurality of solar cells,
A resin-made first base material provided on the first surface side of the plurality of solar cells and having a curved shape convex in the opposite direction to the plurality of solar cells;
A second base material provided on the second surface side of the solar cell and having a curved shape convex in the direction of the first base material;
A sealing layer filled between the first substrate and the second substrate;
A buffer layer provided between the first substrate and the plurality of solar cells, and having a lower shear modulus than the sealing layer;
With
The said buffer layer is a solar cell module comprised by the some buffer film arrange | positioned at 1 sheet form.
There is a gap between the adjacent buffer films,
The solar cell module according to claim 1, wherein the gap is filled with the sealing layer.
The solar cell module according to claim 1, wherein the plurality of buffer films are arranged adjacent to each other in a state where respective end portions overlap each other in the thickness direction of the module.
The solar cell module according to any one of claims 1 to 3, wherein at least one of the end portions of the buffer film is provided at a position overlapping a gap between the solar cells and a thickness direction of the module.
The solar cell module according to any one of claims 1 to 4, further comprising a concealing layer that covers an end portion of the buffer film between the first base material and the buffer layer.
The plurality of buffer films are arranged in the X direction, which is one of the surface directions of the first base material,
Wherein X direction length W 2 of the plurality of buffer film, the first substrate is below the length W 1 of the following, a solar cell module according to any one of claims 1 to 5.
Here, the length W 1 is
Arbitrary points arranged in the Y direction of the first base material orthogonal to the X direction are A1, A2,
A line connecting A1 and A2 with the shortest distance along the surface of the first substrate is α, the length of the line α is L 1 ,
The points drawn by drawing a perpendicular γ of the same length along the surface of the first base material from A1, A2 to the line α are B1, B2,
A line connecting B1 and B2 with the shortest distance along the surface of the first substrate is β, the length of the line β is L 2 ,
When a was a length of a perpendicular γ when the length L 2 of the line β is equal to or more than 99.0% of the length L 1 of the line alpha.
The solar cell module according to any one of claims 1 to 6, wherein the plurality of buffer films have a shear elastic modulus of 0.1 MPa or less.
The solar cell module according to any one of claims 1 to 7, further comprising a barrier layer having a lower oxygen permeability than the first base material between the buffer layer and the plurality of solar cells.
A plurality of strings including the plurality of solar cells disposed at intervals in a first curve direction which is an extending direction of the first curve convex to the light receiving side;
A barrier film provided between the first substrate and the plurality of solar cells, having a smaller linear expansion coefficient than the first substrate;
Further comprising
The solar cell module according to any one of claims 1 to 8, wherein the barrier film has irregularities in a portion between two strings adjacent to each other in the first curve direction.
The unevenness is provided on both the light receiving side surface of the barrier film and the back side of the film,
When viewed from the thickness direction of the barrier film, the concave portion on the front surface of the barrier film overlaps the convex portion on the back surface of the barrier film, and the concave portion on the back surface of the barrier film is the surface of the barrier film. The solar cell module according to claim 9, wherein the solar cell module overlaps with the convex portion.
The solar cell module according to claim 9 or 10, wherein the barrier film has a thickness of 110 µm or less.