WO2018061789A1

WO2018061789A1 - Solar cell module

Info

Publication number: WO2018061789A1
Application number: PCT/JP2017/033192
Authority: WO
Inventors: 朗通前川; 村上　洋平; 治寿橋本
Original assignee: パナソニックＩｐマネジメント株式会社
Priority date: 2016-09-29
Filing date: 2017-09-14
Publication date: 2018-04-05
Also published as: JPWO2018061789A1; CN109716537A; JP6731660B2

Abstract

A solar cell module (1) comprises: solar cells (10); a filler member (60) containing ethylene vinyl acetate; a light-reflecting layer (32) which is provided so as to protrude beyond the edges of the solar cells (10), and is sandwiched between the solar cells (10) and the filler member (60); and an acid-resistant layer (33) which is laminated on the light-reflecting layer (32) between the filler member (60) and the light-reflecting layer (32).

Description

Solar cell module

The present invention relates to a solar cell module.

Conventionally, a solar cell module includes a solar cell and a reflecting member disposed on the light receiving surface side of the solar cell (for example, Patent Document 1). The solar battery cell and the reflecting member are embedded in a filler containing ethylene vinyl acetate.

In this solar cell module, in order to effectively use the sunlight irradiated to the gap between the solar cells, the light reflecting member that protrudes from the light receiving surface of the solar cell and is inclined with respect to the light receiving surface is provided with the solar cell. It is provided in the gap between cells.

JP 2013-98496 A

However, since solar cell modules are usually installed outdoors, they are easily exposed to rain. In this case, when vinyl penetrates into the filling member, ethylene vinyl acetate is decomposed and acetic acid is generated. Since the light reflecting layer is mainly made of metal, acetic acid generated inside the filling member corrodes the light reflecting layer, and the metallic luster is lost. As a result, the light reflecting performance of the light reflecting layer is lowered.

An object of the present invention is to provide a solar cell module capable of suppressing a decrease in light reflection performance of a light reflection layer by suppressing corrosion of the light reflection layer.

In order to achieve the above object, one aspect of a solar cell module according to the present invention is provided so as to project from a solar cell, a filling member containing ethylene vinyl acetate, and an end of the solar cell, A light reflecting layer sandwiched between the solar battery cell and the filling member; and an acid-resistant layer laminated on the light reflecting layer between the filling member and the light reflecting layer.

Moreover, in order to achieve the said objective, the one aspect | mode of the solar cell module which concerns on this invention is a filling member containing the solar cell string provided with the several photovoltaic cell electrically connected by the wiring material, and ethylene vinyl acetate And a light reflection layer that is provided so as to protrude from an end of the solar battery cell at a position that does not overlap with the wiring member, and sandwiched between the solar battery cell and the filler member, the filler member, and the An acid resistant layer laminated on the light reflecting layer is provided between the light reflecting layer and the light reflecting layer.

Moreover, in order to achieve the said objective, one aspect | mode of the solar cell module which concerns on this invention is a solar cell, the filling member containing ethylene vinyl acetate, and the light reflection layer provided so that it may be covered with the said filling member, And an acid resistant layer laminated on the light reflecting layer between the filling member and the light reflecting layer.

According to the present invention, the deterioration of the light reflection performance of the light reflection layer can be suppressed by suppressing the corrosion of the light reflection layer.

FIG. 1 is a plan view of a solar cell module according to an embodiment. FIG. 2 is a partially enlarged plan view when the solar cell module according to the embodiment is viewed from the surface side. FIG. 3 is a cross-sectional view of the solar cell module according to the embodiment taken along line III-III in FIG. 4 is a partially enlarged cross-sectional view of the solar cell module according to the embodiment taken along line IV-IV in FIG. FIG. 5 is a partially enlarged cross-sectional view of a solar cell module according to a modification of the embodiment. FIG. 6 is a partial enlarged cross-sectional view of a solar cell module according to a modification.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Accordingly, numerical values, shapes, materials, components, arrangement positions and connection forms of components, and steps and order of steps shown in the following embodiments are merely examples and are not intended to limit the present invention. . Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

In addition, the description of “substantially **” is intended to include not only exactly the same, but also those that are recognized as substantially the same, with “substantially identical” taken as an example.

Each figure is a schematic diagram and is not necessarily shown strictly. Moreover, in each figure, the same code | symbol is attached | subjected to the substantially same structure, The overlapping description is abbreviate | omitted or simplified.

(Embodiment)
[Configuration of solar cell module]
First, a schematic configuration of the solar cell module 1 according to the present embodiment will be described with reference to FIGS. FIG. 1 is a plan view of a solar cell module according to an embodiment. FIG. 2 is a partially enlarged plan view when the solar cell module according to the embodiment is viewed from the surface side. FIG. 3 is a cross-sectional view of the solar cell module according to the embodiment taken along line III-III in FIG. 4 is a partially enlarged cross-sectional view of the solar cell module according to the embodiment taken along line IV-IV in FIG.

In FIG. 1, the direction in which twelve solar cells 10 arranged at equal intervals along the row direction are arranged is defined as the X-axis direction. The direction in which the six solar cell strings 10S are arranged in the column direction so that the two adjacent solar cell strings 10S are parallel to each other is defined as the Y-axis direction. The vertical direction is defined as the Z-axis direction. In FIG. 1, the X-axis direction, the Y-axis direction, and the Z-axis direction change depending on the usage mode, and are not limited to this. The same applies to each figure after FIG.

The “front surface” of the solar cell module 1 means a surface on which light can be incident on the “front surface” side of the solar cell, and the “back surface” of the solar cell module 1 means the surface on the opposite side. The “front surface” of the solar cell module 1 is the upper side (plus Z-axis direction), and the “back surface” of the solar cell module 1 is the lower side (minus Z-axis direction).

As shown in FIGS. 1 to 3, the solar cell module 1 includes a plurality of solar cells 10, a wiring member 20, a light reflecting member 30, a surface protection member 40, a back surface protection member 50, and a filling member 60. And a frame 70. The solar cell module 1 has a structure in which a plurality of solar cells 10 are sealed with a filling member 60 between a surface protection member 40 and a back surface protection member 50.

As shown in FIG. 1, the planar view shape of the solar cell module 1 is, for example, a substantially rectangular shape. As an example, the solar cell module 1 has a substantially rectangular shape with a horizontal length of about 1600 mm and a vertical length of about 800 mm. In addition, the shape of the solar cell module 1 is not limited to a shape in which six solar cell strings 10S each including twelve solar cells 10 are arranged, and is not limited to a rectangular shape.

[Solar cells]
The solar cell 10 is a photoelectric conversion element (photovoltaic element) that converts light such as sunlight into electric power. A plurality of solar cells 10 are arranged in a matrix (matrix) on the same plane.

A plurality of solar cells 10 arranged in a straight line form a string by connecting two adjacent solar cells 10 with a wiring material 20. The plurality of solar cells 10 are stringed by being electrically connected by the wiring member 20. A plurality of solar cells 10 in one solar cell string 10S are connected in series by a wiring member 20.

In the present embodiment, twelve solar cells 10 arranged at equal intervals along the row direction (X-axis direction) are connected by the wiring member 20 to constitute one solar cell string 10S. . More specifically, each solar cell string 10 </ b> S is configured by sequentially connecting two solar cells 10 adjacent in the row direction (X-axis direction) with three wiring members 20. All the solar cells 10 corresponding to one row arranged along the direction are connected.

A plurality of solar cell strings 10S are formed. The plurality of solar cell strings 10S are arranged along the column direction (Y-axis direction). In the present embodiment, the six solar cell strings 10S are arranged at equal intervals along the column direction so as to be parallel to each other.

Note that the first solar cell 10 in each solar cell string 10S is connected to the connection wiring via the wiring member 20 at both ends in the row direction. Further, the last solar cell 10 in each solar cell string 10 </ b> S is connected to the connection wiring via the wiring member 20. Thereby, a plurality of (six in FIG. 1) solar cell strings 10S are connected in series or in parallel to constitute a cell array. In the present embodiment, six adjacent solar battery strings 10S are connected in series to form one series connection body (a structure in which 24 solar battery cells 10 are connected in series).

As shown in FIG. 1 and FIG. 2, the solar cells 10 adjacent in the row direction and the column direction are arranged with a gap from other adjacent solar cells 10. As will be described later, the light reflecting member 30 is disposed across the gap.

In the present embodiment, the planar view shape of the solar battery cell 10 is a substantially rectangular shape. Specifically, the solar battery cell 10 has a shape in which a 125 mm square square is missing, and a straight long side and a linear or non-linear short side are alternately connected to approximately eight. It is a square shape. That is, one solar cell string 10S is configured such that one side of two adjacent solar cells 10 faces each other. In addition, the shape of the photovoltaic cell 10 is not restricted to a substantially rectangular shape.

The solar cell 10 has a semiconductor pn junction as a basic structure, and as an example, the n-type single crystal silicon substrate that is an n-type semiconductor substrate and one main surface side of the n-type single crystal silicon substrate are sequentially formed. , An n-type amorphous silicon layer and an n-side electrode, and a p-type amorphous silicon layer and a p-side electrode sequentially formed on the other main surface side of the n-type single crystal silicon substrate. An i-type amorphous silicon layer or a silicon oxide layer between the n-type single crystal silicon substrate and the n-type amorphous silicon layer or between the n-type single crystal silicon substrate and the p-type amorphous silicon layer Such a passivation layer may be provided to suppress recombination of the generated carriers. The n-side electrode and the p-side electrode are transparent electrodes such as ITO (Indium Tin Oxide).

In addition, in this Embodiment, although the photovoltaic cell 10 is arrange | positioned so that the n side electrode may become the main light-receiving surface side (surface protection member 40 side of FIG. 3) of the solar cell module 1, it does not restrict to this. It is not a thing. Further, if the solar cell module 1 is a single-sided light receiving system, the electrode located on the back side (p-side electrode in the present embodiment) does not need to be transparent, and may be a metal electrode having reflectivity, for example. .

As shown in FIG. 3, in each solar battery cell 10, the surface is the surface on the surface protection member 40 side, and the back surface is the surface on the back surface protection member 50 side. A front side collector electrode 11 and a back side collector electrode 12 are formed in the solar battery cell 10. The front-side collector electrode 11 is electrically connected to the surface-side electrode (for example, n-side electrode) of the solar battery cell 10. The back side collector electrode 12 is electrically connected to the back side electrode (for example, p side electrode) of the photovoltaic cell 10.

Each of the front-side collector electrode 11 and the back-side collector electrode 12 includes, for example, a plurality of finger electrodes formed in a straight line so as to be orthogonal to the extending direction of the wiring member 20, and finger fingers connected to these finger electrodes It is comprised by the several bus-bar electrode formed in linear form along the direction (extension direction of the wiring material 20) orthogonal to an electrode. For example, the number of bus bar electrodes is the same as that of the wiring member 20 and is three in the present embodiment. In addition, although the front side collector electrode 11 and the back side collector electrode 12 are mutually the same shape, it is not limited to this.

The front side collector electrode 11 and the back side collector electrode 12 are made of a low resistance conductive material such as silver (Ag). For example, the front side collector electrode 11 and the back side collector electrode 12 can be formed by screen-printing a conductive paste (silver paste or the like) in which a conductive filler such as silver is dispersed in a binder resin in a predetermined pattern.

In the solar battery cell 10, both the front surface and the back surface can be used as the light receiving surface. When light enters the solar battery cell 10, carriers are generated in the photoelectric conversion part of the solar battery cell 10. The generated carriers are collected by the front side collector electrode 11 and the back side collector electrode 12 and flow into the wiring member 20. Thus, by providing the front side collector electrode 11 and the back side collector electrode 12, the carrier generated in the solar battery cell 10 can be efficiently taken out to the external circuit.

[Connection wiring]
The wiring member 20 (interconnector) electrically connects two adjacent solar cells 10 in the solar cell string 10S. In the present embodiment, two adjacent solar cells 10 are connected by three wiring members 20 arranged substantially in parallel with each other. Each wiring member 20 extends along the X-axis direction with respect to two solar cells 10 arranged in the X-axis direction.

The wiring member 20 is a long conductive wiring, and is, for example, a ribbon-like metal foil or a fine-line metal wire. The wiring member 20 can be produced, for example, by cutting a metal foil such as a copper foil or a silver foil that is entirely covered with solder, silver, or the like into a strip shape having a predetermined length.

For each wiring member 20, one end of the wiring member 20 is disposed on the surface of one of the two adjacent solar cells 10, and the other end of the wiring member 20 is adjacent to 2. It arrange | positions at the back surface of the other photovoltaic cell 10 among the two photovoltaic cells 10. FIG.

Each wiring member 20 electrically connects the front side collector electrode 11 of one solar cell 10 and the back side collector electrode 12 of the other solar cell 10 in two adjacent solar cells 10. Yes. For example, the wiring member 20 and the bus bar electrodes of the front-side collector electrode 11 and the back-side collector electrode 12 of the solar battery cell 10 are joined by a conductive adhesive such as solder or resin containing conductive particles.

[Light reflecting member]
As shown in FIG. 4, the light reflecting layer 32 is disposed on the back surface side of the solar battery cell 10. The light reflecting layer 32 has light reflectivity at least on the light receiving surface side, and reflects incident light.

The light reflecting member 30 is disposed so as to be located in a gap between two adjacent solar cells 10. In the present embodiment, the light reflecting member 30 is provided in each of the two adjacent solar cells 10 so as to straddle the gap between the two adjacent solar cells 10 in the Y-axis direction. Since each light reflecting member 30 is disposed so as to straddle the gap between two adjacent solar cells 10, the width of each light reflecting member 30 is larger than the gap between the two adjacent solar cells 10. It has become.

Each gap between two adjacent solar cells 10 is between one side of one solar cell 10 and one side of the other solar cell 10 facing this one side. That is, the gap between the two adjacent solar cells 10 is long in the row direction and extends in a direction parallel to the solar cell string 10S. That is, the light reflecting member 30 is two solar cells 10 that are adjacent to each other with a gap between them, and one solar cell on the back side of the two adjacent solar cells 10 that are not connected by the wiring member 20. It is provided so as to straddle from the cell 10 to the other solar battery cell 10.

In the present embodiment, the light reflecting member 30 is provided with two light reflecting members 30 in one solar battery cell 10 except for the solar battery cell 10 of the outermost peripheral solar battery string 10S. The light reflecting member 30 has a tape shape extending in the row direction of the solar cell string 10S, and has a long rectangular shape as an example. The light reflecting member 30 is attached along one side of the solar battery cell 10 so that one end in the width direction (Y-axis direction) and the end of the solar battery 10 overlap each other. That is, the light reflecting member 30 is affixed substantially parallel to the wiring member 20.

The light reflecting member 30 has a substrate layer 31, a light reflecting layer 32, and an acid resistant layer 33, and is laminated in this order toward the minus Z-axis direction.

In the present embodiment, the light reflecting member 30 is adhered to the solar battery cell 10 by the adhesive layer 34 provided on the back surface side of the solar battery cell 10. The adhesive layer 34 is a transparent adhesive member that is provided so as to be sandwiched between the substrate layer 31 and the solar battery cell 10 and is formed on the solar battery cell 10 side of the substrate layer 31. The adhesive layer 34 is provided on the entire surface of the substrate layer 31. That is, the adhesive layer 34 covers the entire solar cell 10 side of the light reflecting layer 32.

The adhesive layer 34 is made of a material softer than the substrate layer 31. For example, the adhesive 36 is a heat-sensitive adhesive or pressure-sensitive adhesive made of ethylene vinyl acetate (which is an abbreviation for ethylene vinyl acetate copolymer, commonly known as EVA: Ethylene-Vinyl Acetate). Thereby, the light reflection member 30 can be bonded and fixed to the solar battery cell 10 by thermocompression bonding.

Thus, by using a material softer than the substrate layer 31 as the material of the adhesive layer 34, when the light reflecting member 30 is bonded to the solar battery cell 10 via the adhesive layer 34, the back surface of the solar battery cell 10 and A fillet of the adhesive layer 34 is formed on the side surface. As a result, since the contact area between the solar battery cell 10 and the adhesive layer 34 can be increased, the adhesive force between the solar battery cell 10 and the light reflecting member 30 is improved.

In the present embodiment, the substrate layer 31, the light reflection layer 32, and the acid resistant layer 33 are used as the light reflecting member 30. However, an adhesive layer 34 is added to the substrate layer 31, the light reflective layer 32, and the acid resistant layer 33. The light reflecting member 30 may be used, and the substrate layer 31 and the light reflecting layer 32 may be used as the light reflecting member 30. That is, the light reflecting member 30 may have a four-layer structure including the substrate layer 31, the light reflecting layer 32, the acid resistant layer 33, and the adhesive layer 34, or a two-layer structure including the substrate layer 31 and the light reflecting layer 32. .

The substrate layer 31 is made of, for example, polyethylene terephthalate (PET) or acrylic. The light reflecting layer 32 is a metal film made of a metal such as aluminum or silver, and is an aluminum vapor deposition film in the present embodiment.

The light reflection layer 32 is sandwiched between the solar battery cell 10 and the filling member 60. That is, the substrate layer 31 is provided between the adhesive layer 34 on the back surface of the solar battery cell 10 and the light reflecting layer 32. The light reflecting layer 32 is provided in the solar battery cell 10 via the substrate layer 31 and the adhesive layer 34. In the present embodiment, similarly to the light reflecting layer 32, the substrate layer 31 is provided so as to straddle the gap between two adjacent solar battery cells 10.

The substrate layer 31 exists on the main light receiving surface side of the solar cell module 1 with respect to the light reflecting layer 32. Therefore, the material of the substrate layer 31 is composed of a translucent material such as a transparent material in order to reflect the light incident from the main light receiving surface of the solar cell module 1 on the surface of the light reflecting layer 32 on the main light receiving surface side. Has been.

The specific material of the substrate layer 31 is, for example, polyethylene terephthalate (PET) or acrylic. In the present embodiment, the substrate layer 31 is a transparent PET sheet.

An uneven shape processing structure 31 a is formed on the back surface of the substrate layer 31. In the substrate layer 31, for example, the height between the concave portion (valley portion) and the convex portion (peak portion) is 5 μm or more and 100 μm or less, and the interval (pitch) between adjacent convex portions is 20 μm or more and 400 μm or less. In this Embodiment, the height between a recessed part and a convex part is 12 micrometers, and the space | interval (pitch) of an adjacent convex part is 40 micrometers.

The shape processing structure 31 a of the substrate layer 31 has, for example, a triangular groove shape along the longitudinal direction of the light reflecting member 30. However, the shape of the shape processing structure 31a is not limited to this, and a conical shape, a quadrangular pyramid shape, a polygonal pyramid shape, or a combination of these shapes, as long as it can scatter light It may be a shape or the like.

The light reflecting layer 32 is formed on the back surface of the shape processing structure 31a. The light reflection layer 32 is a metal film (metal reflection film) made of a metal such as aluminum or silver. The light reflecting layer 32 made of a metal film is formed on the back surface of the shape processing structure 31a of the substrate layer 31, for example, by vapor deposition. Therefore, the surface shape of the light reflection layer 32 becomes an uneven shape following the uneven shape of the shape processing structure 31a. That is, the light reflection layer 32 has a repeated structure of a plurality of convex portions and a plurality of concave portions. In the present embodiment, the light reflecting layer 32 is an aluminum vapor deposition film.

The acid resistant layer 33 is a thin film formed on the back surface of the light reflecting layer 32, and has a thickness of about 30 nm, for example. The acid resistant layer 33 is a layer made of, for example, an inorganic optical layer, a metal layer, a resin layer, or the like. Examples of the inorganic optical layer include magnesium fluoride, silicon dioxide, lithium fluoride, and calcium fluoride. An example of the metal layer is nickel, silver, or the like. Examples of the resin layer are polyolefin resin, acrylic resin, epoxy resin, fluororesin, polyvinylidene chloride, polycarbonate, and the like. The inorganic optical layer, the metal layer, the resin layer, and the like have a property of suppressing transmission of acetic acid derived (generated) from the filling member 60 containing ethylene vinyl acetate.

The acid resistant layer 33 is laminated on the light reflecting layer 32 between the filling member 60 and the light reflecting layer 32. The light reflecting layer 32 is covered from the back side so that the light reflecting layer 32 does not come into contact with the filling member 62. That is, the acid resistant layer 33 covers the light reflecting layer 32 so that even if acetic acid is generated in the filling member 62 containing ethylene vinyl acetate, the light reflecting layer 32 is not dissolved by acetic acid. In the present embodiment, the acid resistant layer 33 is formed at the interface of the light reflecting layer 32.

The acid resistant layer 33 is formed on the back surface of the shape processing structure 31a of the substrate layer 31, for example, by vapor deposition. Therefore, since the surface shape of the light reflecting layer 32 is an uneven shape following the uneven shape of the shape processing structure 31 a, the acid-resistant layer 33 also becomes an uneven shape following the uneven shape of the light reflecting layer 32. That is, the acid resistant layer 33 also has a repeated structure of a plurality of convex portions and a plurality of concave portions. Further, when the acid-resistant layer 33 is formed of a resin layer, the surface of the acid-resistant layer 33 has a concavo-convex shape lower than that of the shape processed structure 31a or a shape that does not have a concavo-convex shape.

The light reflecting member 30 has a laminated structure of a substrate layer 31, a light reflecting layer 32, and an acid resistant layer 33. That is, the light reflecting member 30 having the light reflecting layer 32 formed on the back surface of the substrate layer 31 is used. The light reflecting member 30 has a light reflecting function of reflecting incident light.

As shown in FIGS. 1 and 2, a plurality of light reflecting members 30 are provided. Each light reflecting member 30 is a tape-like light reflecting sheet extending in the longitudinal direction of the solar cell string 10S, and has a long rectangular shape and a thin plate shape as an example. Each light reflecting member 30 has, for example, a length of 100 mm to 130 mm, a width of 1 mm to 20 mm, and a thickness of 0.05 mm to 0.5 mm. As an example, the light reflecting member 30 has a length of 125 mm, a width of 5 mm, and a thickness of 0.1 mm.

In the present embodiment, since the light reflecting member 30 has the uneven light reflecting layer 32, the light incident on the light reflecting member 30 can be diffusely reflected in a predetermined direction. That is, the light reflection member 30 is a light diffusion reflection sheet that functions as a light diffusion reflection member.

In the present embodiment, the light reflecting member 30 is disposed on the back side of the solar battery cell 10. When the light reflecting member 30 is arranged on the surface side of the solar battery cell 10, an effective area (power generation area) of the solar battery cell 10 is shielded by the light reflecting member 30 in a portion where the light reflecting member 30 and the solar battery cell 10 overlap. Although there is a possibility that a light-blocking loss occurs, such a light-blocking loss can be reduced by arranging the light reflecting member 30 on the back surface side of the solar battery cell 10.

3 and 4, the light reflecting member 30 is disposed so that the back surface of the light reflecting layer 32 faces the back surface protecting member 50. That is, the light reflecting member 30 is disposed so that the substrate layer 31 is located on the front surface protection member 40 side and the light reflecting layer 32 is located on the back surface protection member 50 side.

The light reflecting member 30 is sealed by the filling member 60. Specifically, the light reflecting member 30 is sealed with the front surface side filling member 61 and the back surface side filling member 62. More specifically, the surface protection member 40 side (main light receiving surface side) of the light reflecting member 30 is covered with the surface side filling member 61, and the back surface protection member 50 side of the light reflecting member 30 is filled with the back surface side. Covered by a member 62. In other words, the light reflecting member 30 is provided so as to be sandwiched between the solar battery cell 10 and the back surface side filling member 62.

Thus, the gap between two adjacent solar cells 10 (the other solar cells 10 adjacent to the solar cells 10) is covered by the light reflecting member 30 (the light reflecting layer 32).

Thereby, the light incident on the gap between two adjacent solar cells 10 among the light incident on the solar cell module 1 from the main light receiving surface side is the surface protection member 40, the surface side filling member 61, and the adhesive layer 34. Is transmitted through the substrate layer 31 of the light reflecting member 30 and diffusely reflected (scattered) by the uneven shape of the light reflecting layer 32. The diffusely reflected light is reflected at the interface between the surface protection member 40 and the air layer or the interface between the surface protection member 40 and the filling member 60 and guided to the solar battery cell 10. As a result, the two adjacent power generation invalid regions (in this embodiment, the region between the two adjacent solar cell strings 10S, which is the region where the incident light cannot contribute to power generation). The light generation efficiency of the solar cell module 1 is improved by causing light incident on the gap region between the solar cells 10 to effectively contribute to power generation.

[Surface protection member, back surface protection member]
As shown in FIG. 3, the surface protection member 40 is a member that protects the surface on the front side of the solar cell module 1, and the inside of the solar cell module 1 (solar cell 10 or the like) is exposed to outside such as wind and rain or external impact. Protect from the environment. The surface protection member 40 is disposed on the front surface side of the solar battery cell 10 and protects the light receiving surface on the front surface side of the solar battery cell 10.

The surface protection member 40 is made of a translucent member that transmits light in a wavelength band used for photoelectric conversion in the solar battery cell 10. The surface protection member 40 is, for example, a glass substrate made of a transparent glass material, or a resin substrate made of a hard resin material having film-like or plate-like translucency and water shielding properties.

On the other hand, the back surface protection member 50 is a member that protects the back surface of the solar cell module 1 and protects the inside of the solar cell module 1 from the external environment. The back surface protection member 50 is disposed on the back surface side of the solar battery cell 10 and protects the light receiving surface on the back surface side of the solar battery cell 10.

The back surface protection member 50 is a film-like or plate-like resin sheet made of a resin material such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN).

Since the solar cell module 1 in the present embodiment is a single-sided light receiving method, the back surface protection member 50 may be an opaque plate or film. In this case, as the back surface protection member 50, for example, an opaque member (light-shielding member) such as a black member or a laminated film such as a resin film having a metal foil such as an aluminum foil therein may be used. . Note that the back surface protection member 50 is not limited to the light-impermeable member, and may be a light-transmissive member such as a glass sheet or a glass substrate made of a glass material.

A filling member 60 is filled between the front surface protection member 40 and the back surface protection member 50. The front surface protection member 40 and the back surface protection member 50 and the solar battery cell 10 are bonded and fixed by the filling member 60.

[Filling member]
The filling member 60 is disposed between the front surface protection member 40 and the back surface protection member 50. In the present embodiment, the filling member 60 is filled so as to fill a space between the surface protection member 40 and the back surface protection member 50.

The filling member 60 is composed of a front surface side filling member 61 and a back surface side filling member 62. Each of the front surface side filling member 61 and the back surface side filling member 62 covers a plurality of solar cells 10 arranged in a matrix.

The front surface side filling member 61 is formed so as to cover the solar battery cell 10 and the light reflection layer 32 from the front surface side of each solar battery cell 10. Specifically, the surface-side filling member 61 is formed so as to cover all the solar cells 10 and all the light reflecting members 30 from the surface protection member 40 side. The front side filling member 61 may not contain EVA and may be the same material as the back side filling member 62.

The back surface side filling member 62 is formed so as to cover the solar battery cell 10 and the light reflection layer 32 from the back surface side of each solar battery cell 10. Specifically, the back surface side filling member 62 is formed so as to cover all the solar cells 10 and all the light reflecting members 30 from the back surface protection member 50 side. The back surface side filling member 62 is made of a material containing EVA.

The plurality of solar cells 10 are entirely covered with the filling member 60 by performing a laminating process (lamination process) while being sandwiched between, for example, a sheet-like front side filling member 61 and a back side filling member 62.

Specifically, after a plurality of solar cells 10 are connected by the wiring member 20 to form the solar cell string 10S, the plurality of solar cell strings 10S are sandwiched between the front surface side filling member 61 and the back surface side filling member 62. Furthermore, the surface protection member 40 and the back surface protection member 50 are disposed above and below, and thermocompression bonding is performed in a vacuum at a temperature of, for example, 100 ° C. or higher. By this thermocompression bonding, the front surface side filling member 61 and the back surface side filling member 62 are heated and melted to form a filling member 60 that seals the solar battery cell 10.

The surface-side filling member 61 before the lamination process is a resin sheet made of, for example, a resin material such as EVA or polyolefin, and is disposed between the plurality of solar cells 10 and the surface protection member 40. The front-side filling member 61 is mainly filled by a laminating process so as to fill a gap between the solar battery cell 10 and the surface protection member 40.

The front-side filling member 61 is made of a translucent material. In the present embodiment, a transparent resin sheet made of EVA is used as the front-side filling member 61 before the lamination process.

The back surface side filling member 62 before the laminating process is a white resin sheet made of a resin material such as EVA, and is disposed between the plurality of solar cells 10 and the back surface protection member 50. The back surface side filling member 62 is mainly filled by a laminating process so as to fill a gap between the solar battery cell 10 and the back surface protection member 50.

Since the solar cell module 1 according to the present embodiment is a single-sided light receiving method, the back surface side filling member 62 is not limited to a light-transmitting material, and may be made of a coloring material such as a black material or a white material. . As an example, a white resin sheet made of EVA is used as the back surface side filling member 62 before the lamination process.

[flame]
As shown in FIG. 1, the frame 70 is an outer frame that covers the peripheral edge of the solar cell module 1. The frame 70 is, for example, an aluminum frame (aluminum frame) made of aluminum. Four frames 70 are used, and are mounted on each of the four sides of the solar cell module 1. The frame 70 is fixed to each side of the solar cell module 1 with an adhesive, for example.

Although not shown, the solar cell module 1 is provided with a terminal box for taking out the electric power generated by the solar cells 10. The terminal box is fixed to the back surface protection member 50, for example. The terminal box contains a plurality of circuit components mounted on the circuit board.

[Effects]
Next, the effect of the solar cell module 1 in the present embodiment will be described.

As described above, the solar cell module 1 according to Embodiment 1 is provided so as to project from the solar cell 10, the filling member 60 containing ethylene vinyl acetate, and the end of the solar cell 10. A light reflecting layer 32 sandwiched between the cell 10 and the filling member 60 and an acid resistant layer 33 laminated on the light reflecting layer 32 between the filling member 60 and the light reflecting layer 32 are provided.

According to this configuration, even if acetic acid is generated in the filling member 62 due to water that has permeated the filling member 62, the acid resistant layer 33 is laminated on the light reflecting layer 32 between the filling member 60 and the light reflecting layer 32. Therefore, permeation of acetic acid generated in the filling member 60 can be suppressed. For this reason, the light reflection layer 32 is hardly corroded by acetic acid generated in the filling member 62. As a result, the light reflecting performance of the light reflecting layer 32 is unlikely to deteriorate.

Therefore, according to the solar cell module 1, the deterioration of the light reflection performance of the light reflection layer 32 can be suppressed by suppressing the corrosion of the light reflection layer 32.

Moreover, in the solar cell module 1 according to Embodiment 1, a solar cell string 10S including a plurality of solar cells 10 electrically connected by the wiring member 20, a filling member 60 containing ethylene vinyl acetate, and a wiring member The light reflecting layer 32 is provided so as to protrude from the end of the solar battery cell 10 at a position that does not overlap with the solar battery cell 10, and is sandwiched between the solar battery cell 10 and the filling member 60. And an acid resistant layer 33 laminated on the light reflecting layer 32. This configuration also has the same effect.

Further, in the solar cell module 1 according to Embodiment 1, the acid-resistant layer 33 has lower acetic acid solubility than the light reflecting layer 32 or lower acetic acid permeability than the filling member 60.

According to this configuration, since the acid-resistant layer 33 is more soluble in acetic acid than the light reflecting layer 32, the acid-resistant layer 33 is difficult to dissolve. In addition, since the acid-resistant layer 33 has a lower acetic acid permeability than the filling member 60, it is difficult for acetic acid to contact the light reflecting layer 32. For these reasons, the light reflecting layer 32 covered with the substrate layer 31 and the acid resistant layer 33 is hardly corroded. As a result, the light reflecting performance of the light reflecting layer 32 is unlikely to deteriorate.

In the solar cell module 1 according to Embodiment 1, the acid-resistant layer 33 is an inorganic optical layer, a metal layer, or a resin layer that suppresses contact of acetic acid derived from ethylene vinyl acetate with the light reflecting layer 32. .

If the acid-resistant layer 33 is an inorganic optical layer, a metal layer, or a resin layer, the contact of acetic acid with the light reflecting layer 32 can be suppressed. That is, in the solar cell module 1, it is difficult to impair the light reflection performance of the light reflection layer 32.

Moreover, in the solar cell module 1 according to Embodiment 1, the surface of the light reflecting layer 32 has a triangular groove-shaped repeating structure formed in a direction along the end of the solar cell 10.

Moreover, the solar cell module 1 according to Embodiment 1 further includes a surface protection member 40 provided on the front surface side of the solar cell 10 and a back surface protection member 50 provided on the back surface side of the solar cell 10. In addition, the filling member 60 is a front surface side of the solar battery cell 10 and is provided between the solar battery cell 10 and the surface protection member 40. A back surface side filling member 62 provided between the battery cell 10 and the back surface protection member 50. The light reflecting layer 32 is arranged so that the light reflected by the light reflecting layer 32 is reflected by the interface of the surface protection member 40 and guided to the solar battery cell 10.

As a result, the light incident on the gap between the two adjacent solar cells 10 out of the light incident on the solar cell module 1 from the main light receiving surface side is transmitted through the surface-side filling member 61, for example, and the light reflecting member. 30, passes through the substrate layer 31, and is diffusely reflected (scattered) by the uneven shape of the light reflecting layer 32. The diffusely reflected light is totally reflected at the interface between the surface protection member 40 and the air layer or at the interface between the surface protection member 40 and the surface-side filling member 61 and guided to the solar battery cell 10. As a result, two adjacent solar cells that are ineffective regions (regions in the present embodiment that are gaps between two adjacent strings 10S and that cannot make incident light contribute to power generation). Since the light incident on the region between the gaps 10 can also contribute to power generation effectively, the power generation efficiency of the solar cell module 1 is improved. The same applies when light enters from the back side of the solar cell module 1.

In the solar cell module 1 according to Embodiment 1, the surface of the light reflection layer 32 has a triangular groove-shaped repetitive structure formed in a direction crossing the direction in which adjacent solar cell strings 10S are arranged. This configuration also has the same effect.

Moreover, in the solar cell module 1 according to Embodiment 1, a plurality of solar cell strings 10S are provided. And the light reflection layer 32 is provided so that it may straddle from the one photovoltaic cell 10 of the adjacent photovoltaic cell strings 10S to the other photovoltaic cell 10 of the adjacent photovoltaic cell strings 10S.

According to this configuration, the light incident on the region of the gap between the two adjacent solar cells 10 can be more effectively contributed to the power generation, so that the power generation efficiency of the solar cell module 1 is improved.

When the light reflecting member 30 is disposed on the back surface side of the solar battery cell 10, the effective area (power generation area) of the solar battery cell 10 is shielded by the light reflecting member 30 in the overlapping portion of the light reflecting member 30 and the solar battery cell 10. May cause a light-shielding loss. By disposing the light reflecting member 30 on the back surface side of the solar battery cell 10, such a light shielding loss can be reduced.

(Modification of the embodiment)
FIG. 5 is a partial enlarged cross-sectional view of a solar cell module 1 according to a modification of the embodiment.

As shown in FIG. 5, the solar cell module 1 in the present modification is different from the embodiment in that the light reflecting member 30 is provided on the surface side of the solar cell 10. In the modification, the light reflecting member 30 is different from the embodiment only in that the light reflecting member 30 is provided in a plane-symmetrical position with respect to the plane defined in the X-axis direction and the Y-axis direction. Are the same, the same reference numerals are assigned to the same components, and descriptions thereof are omitted.

In the solar cell module 1 in the present modification, the light reflecting member 30 is provided in each of the two adjacent solar cells 10 so as to straddle the gap between the two adjacent solar cells 10 in the Y-axis direction. Yes. That is, the light reflecting member 30 is provided so as to straddle from one solar battery cell 10 to the other solar battery cell 10 on the surface side of two adjacent solar battery cells 10 arranged with a gap.

In this modification, the light reflecting member 30 includes a substrate layer 31, a light reflecting layer 32, and an acid resistant layer 33, and is laminated in this order toward the plus Z-axis direction.

The light reflecting member 30 is adhered to the surface side of the solar cell 10 by an adhesive layer 34 provided on the surface side of the solar cell 10. The adhesive layer 34 is a transparent adhesive member that is provided so as to be sandwiched between the substrate layer 31 and the solar battery cell 10 and is formed on the solar battery cell 10 side of the substrate layer 31.

The acid resistant layer 33 is a thin film formed on the surface of the light reflecting layer 32. The acid resistant layer 33 covers the light reflecting layer 32 from the surface side so that the light reflecting layer 32 does not contact the filling member 62. That is, the acid-resistant layer 33 is formed so that the light reflecting layer 32 is in close contact with the light reflecting layer 32 so that acetic acid is not in contact with the light reflecting layer 32 even if acetic acid is generated in the filling member 62 containing ethylene vinyl acetate. Covering.

The acid resistant layer 33 is a transparent material having translucency. That is, when the acid-resistant layer 33 is an inorganic optical layer, for example, a transparent material such as magnesium fluoride, silicon dioxide, lithium fluoride, or calcium fluoride is used for the acid-resistant layer 33. When the acid resistant layer 33 is a resin layer, for example, a transparent material such as polyolefin resin, acrylic resin, epoxy resin, fluororesin, polyvinylidene chloride, and polycarbonate is used for the acid resistant layer 33. Furthermore, when the acid resistant layer 33 is a metal layer, the metal layer may have a light reflecting function. In particular, the acid resistant layer 33 may be made of silver having a higher light reflectance than other metals. In this case, the light that has passed through the surface protection member 40 and the filling member 61 also passes through the acid-resistant layer 33 and is scattered by the light reflecting layer 32, so that the light reflecting function of the light reflecting member 30 is not impaired.

In this modification, the light reflecting member 30 is provided in the power generation invalid region at the end of the solar battery cell 10. Specifically, the light reflecting member 30 is provided at an end portion of the solar battery cell 10 in a region where the front side collecting electrode 11 is not provided. Thereby, productivity can be improved and the power generation capacity of the solar battery cell 10 can be used efficiently.

Such a solar cell module 1 according to this modification includes a solar cell 10, a filling member 60 containing ethylene vinyl acetate, a light reflecting layer 32 provided so as to be covered with the filling member 60, and a filling member 60. Between the light reflecting layer 32, an acid resistant layer 33 laminated on the light reflecting layer 32 is provided. This configuration also has the same effect.

Moreover, the solar cell module 1 according to this modification further includes a wiring member 20 connected to the light receiving surface side of the solar cell 10. The light reflecting layer 32 is provided on the light receiving surface side of the wiring member 20. The acid resistant layer 33 is provided on the light receiving surface side of the light reflecting layer 32.

Even in this case, the light that has entered the gap (power generation invalid region) between two adjacent solar cells 10 in plan view is diffusely reflected (scattered) by the light reflecting member 30 and is transmitted to the solar cells 10. Led. For this reason, since the light incident on the power generation invalid region can be effectively contributed to the power generation, the power generation efficiency of the solar cell module 1 is improved.

Moreover, in the solar cell module 1 according to this modification, the acid-resistant layer 33 is an inorganic optical layer, a metal layer, or a resin layer that suppresses contact of acetic acid derived from ethylene vinyl acetate with the light reflecting layer 32. This configuration also has the same effect.

Further, in the solar cell module 1 according to the present modification, the surface of the light reflection layer 32 further has a triangular groove-shaped repeating structure formed along the extending direction of the wiring member 20. This configuration also has the same effect.

The other operational effects in the present modification also have the same operational effects as in the embodiment.

(Other variations)
As mentioned above, although the solar cell module which concerns on this invention was demonstrated based on embodiment, this invention is not limited to the said embodiment.

For example, in each of the above-described embodiments, the light reflecting member is disposed so as not to overlap the back-side collector electrode of the solar battery cell, but is not limited thereto. Specifically, the light reflecting member may be disposed so as to overlap with the end portion of the back surface side collecting electrode of the solar battery cell (end portion of the finger electrode).

FIG. 6 is a partial enlarged cross-sectional view of a solar cell module according to a modification. Further, in each of the above embodiments, as shown in FIG. 6, the acid-resistant layer 33 does not have to follow the uneven shape of the light reflecting layer 32, and is filled in the recesses between adjacent protrusions. Also good.

In each of the above embodiments, the light reflecting member is disposed in the gap between two adjacent solar cell strings, but is not limited thereto. For example, you may arrange | position a light reflection member in the clearance gap between the adjacent photovoltaic cells in a solar cell string. The light reflecting member has the same configuration as the light reflecting member, and can be attached to the solar battery cell in the same arrangement and shape as the light reflecting member.

Further, in each of the above-described embodiments, the light reflecting member is provided for each gap between the adjacent solar cells in the gap between the two adjacent solar cell strings, but is not limited thereto. For example, the light reflecting member may be provided across a plurality of solar cells along the longitudinal direction of the solar cell string in the gap between two adjacent solar cell strings. As an example, the light reflecting member may be a single long light reflecting sheet covering the entire solar cell string.

Further, in each of the above embodiments, the light reflecting member is provided in the gaps in all the solar cell strings, but may be provided only in a part of the gaps. In other words, there may be a space between solar cells in which no light reflecting member is provided.

In each of the above embodiments, the light reflecting member is provided in the gap in the solar cell string, but may be provided in a region where incident light cannot contribute to power generation other than the gap in the solar cell string. For example, the light reflecting member may be provided on the light receiving surface side of the solar cell and on the light receiving surface of the wiring member. Specifically, a light reflecting member is provided on the light receiving surface side of the wiring material connected to the light receiving surface side of the solar battery cell. This configuration is preferably applied when the surface side filling member of the solar cell module contains ethylene vinyl acetate. The light reflecting member provided on the light receiving surface of the wiring member is configured to be in contact with the surface-side filling member via the acid resistant layer. At this time, the uneven shape of the light reflecting layer is such that a plurality of convex portions and a plurality of concave portions formed along the extending direction of the wiring material are repeatedly arranged in a direction intersecting with the extending direction of the wiring material. Is preferred.

In each of the above embodiments, the semiconductor substrate of the solar cell is an n-type semiconductor substrate, but the semiconductor substrate may be a p-type semiconductor substrate.

In each of the above embodiments, the semiconductor material of the photoelectric conversion part of the solar battery cell is silicon. However, the present invention is not limited to this. As a semiconductor material of the photoelectric conversion portion of the solar battery cell, gallium arsenide (GaAs), indium phosphide (InP), or the like may be used.

In addition, it is realized by arbitrarily combining the components and functions in the embodiment without departing from the scope of the present invention, or the form obtained by subjecting the embodiment to various modifications conceived by those skilled in the art. Forms are also included in the present invention.

DESCRIPTION OF SYMBOLS 1 Solar cell module 10 Solar cell 10S Solar cell string 20 Wiring material 30 Light reflection member 31 Substrate layer 32 Light reflection layer 33 Acid-resistant layer 40 Surface protection member 50 Back surface protection member 60 Filling member 61 Surface side filling member (filling member)
62 Back side filling member (filling member)

Claims

Solar cells,
A filling member comprising ethylene vinyl acetate;
A light reflection layer provided so as to protrude from an end of the solar battery cell, and sandwiched between the solar battery cell and a filling member;
A solar cell module comprising an acid-resistant layer laminated on the light reflecting layer between the filling member and the light reflecting layer.
The solar cell module according to claim 1, wherein the acid-resistant layer has lower solubility in acetic acid than the light reflection layer, or lower acetic acid permeability than the filling member.
The solar cell module according to claim 1, wherein the acid-resistant layer is an inorganic optical layer, a metal layer, or a resin layer that suppresses contact of acetic acid derived from ethylene vinyl acetate with the light reflecting layer.
The solar cell module according to any one of claims 1 to 3, wherein a surface of the light reflecting layer has a triangular groove-shaped repetitive structure formed in a direction along an end portion of the solar battery cell.
A solar cell string comprising a plurality of solar cells electrically connected by a wiring material;
A filling member comprising ethylene vinyl acetate;
A position that does not overlap with the wiring material, provided so as to protrude from an end of the solar battery cell, and a light reflection layer sandwiched between the solar battery cell and the filling member;
A solar cell module comprising an acid-resistant layer laminated on the light reflecting layer between the filling member and the light reflecting layer.
A plurality of the solar cell strings are provided,
The solar cell according to claim 5, wherein the light reflection layer is provided so as to straddle from one solar cell of the adjacent solar cell strings to the other solar cell of the adjacent solar cell strings. module.
7. The solar cell module according to claim 5, wherein a surface of the light reflecting layer has a triangular groove-shaped repetitive structure formed in a direction intersecting a direction in which the adjacent solar cell strings are arranged.
A surface protection member provided on the surface side of the solar cell;
A back surface protection member provided on the back surface side of the solar battery cell,
The filling member is a front surface side of the solar battery cell and provided between the solar battery cell and the surface protection member, and a back surface side of the solar battery cell and the solar battery cell. And a back surface side filling member provided between the back surface protection member,
The solar cell module according to claim 7, wherein the light reflection layer is arranged such that light reflected by the light reflection layer is reflected at an interface of the surface protection member and guided to the solar cell.
Solar cells,
A filling member comprising ethylene vinyl acetate;
A light reflecting layer provided so as to be covered with the filling member;
A solar cell module comprising an acid-resistant layer laminated on the light reflecting layer between the filling member and the light reflecting layer.
Further comprising a wiring material connected to the light receiving surface side of the solar battery cell,
The light reflecting layer is provided on the light receiving surface side of the wiring material,
The solar cell module according to claim 9, wherein the acid resistant layer is provided on the light receiving surface side of the light reflecting layer.
The solar cell module according to claim 10, wherein the acid-resistant layer has lower solubility in acetic acid than the light reflection layer, or lower acetic acid permeability than the filling member.
The solar cell module according to claim 10 or 11, wherein the surface of the light reflecting layer has a triangular groove-shaped repetitive structure formed along the extending direction of the wiring member.