WO2023085428A1

WO2023085428A1 - Solar battery module

Info

Publication number: WO2023085428A1
Application number: PCT/JP2022/042283
Authority: WO
Inventors: 伸匡田飼
Original assignee: 株式会社カネカ
Priority date: 2021-11-15
Filing date: 2022-11-14
Publication date: 2023-05-19
Also published as: JPWO2023085428A1

Abstract

The present invention comprises: a solar battery string (2) that has a plurality of power generation cells (20); a translucent protection plate (3) that is laid over the light incidence side of the solar battery string (2); a sealing material (4) that is interposed between the solar battery string (2) and the protection plate (3); and a decorative layer (5) that is formed so as to be visible through the protection plate (3) from the light incidence side of the protection plate (3) and attenuates or blocks light in the thickness direction. The decorative layer (5) is formed between the protection plate (3) and the solar battery string (2) in the thickness direction.

Description

solar module

Cross-reference to related applications

This application claims priority from Japanese Patent Application No. 2021-185781, and is incorporated into the description of the present specification by reference.

The present invention relates to solar cell modules.

Conventionally, for aesthetic purposes, there has been proposed a solar cell module in which the periphery of the power generating cell is painted (Patent Document 1). This solar cell module includes a back sheet, an adhesive layer formed on the back sheet, and a wiring sheet (conductive sheet member) provided on the back sheet on which the adhesive layer is formed. Further, the solar cell module includes a plurality of solar cells (power generation cells) provided on the wiring sheet, a light receiving surface side sealing material provided on the solar cells in order, and a cover glass.

In this solar cell module, a plurality of cell groups each composed of a row of solar cells are provided. In addition, in the solar cell module, the parts other than the plurality of cell groups are painted black, so that the appearance and design can be improved (paragraph 0090).

Japanese Patent Application Laid-Open No. 2020-170815

By the way, for the purpose of hiding wiring materials and the like to obtain a high degree of design, such a solar cell module may have a portion painted black on the light-receiving surface side. In this configuration, direct sunlight may enter obliquely to the normal direction of the solar cell module depending on the installation angle, orientation, and date and time. In that case, some of the solar cells (power generation cells) block the sunlight due to the portion (coating film) that is painted black. When the amount of light received by a solar cell whose sunlight is blocked by the coating film decreases, the cell becomes a resistor in this module. As a result, the amount of power generated by the cells other than the solar cells in this module may be reduced, and the desired output may not be ensured. In this way, there is a risk that the power generation efficiency of the entire solar cell module, including the solar cells in which the sunlight is not blocked, will be reduced.

An object of the present invention is to provide a solar cell module capable of suppressing a decrease in output even when a decorative layer such as a coating film is formed so as to be visible from the surface of a protective plate (glass).

A solar cell module of the present invention includes a solar cell string having a plurality of power generating cells that generate power by receiving light, a translucent protective plate superimposed on the light incident side of the solar cell string, and the solar cell string. A sealing material interposed between the protective plate and a decorative layer that reduces or blocks light in the thickness direction and is formed so as to be visible through the protective plate from the surface of the protective plate on the light incident side. The decoration layer is formed between the protective plate and the solar cell string in the thickness direction.

Further, in the solar cell module, the decorative layer may be a coating film formed on the rear surface of the protective plate opposite to the light incident side.

Further, in the solar cell module, the coating film may be formed so as not to come into contact with the edge of the protective plate.

In addition, the solar cell module includes a frame portion exposed along the outer edge of the protective plate, and the frame portion is arranged so as not to overlap the decorative layer when the protective plate is viewed in the thickness direction. may be provided in

Further, in the solar cell module, the plurality of power generation cells are elongated, and the plurality of power generation cells are single-ring connected to form the solar cell string. The decorative layers may be formed and arranged at respective positions corresponding to both end portions in the connection direction of the configured solar cell string.

Further, in the solar cell module, the solar cell string further includes a dummy cell that is not electrically connected to any of the plurality of power generation cells and does not contribute to power generation of the solar cell string, and the dummy cell: It may be arranged at a position closer to the decorative layer than any of the plurality of power generation cells in plan view.

FIG. 1 is a schematic plan view of a solar cell module according to this embodiment. FIG. 2 is a schematic cross-sectional view taken along line II-II in FIG. FIG. 3 is a schematic cross-sectional view of a solar cell module according to a comparative example. FIG. 4 is a schematic plan view of a solar cell module according to a modification. 5 is a schematic cross-sectional view taken along the line VV in FIG. 4. FIG.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 5. FIG.

As shown in FIGS. 1 and 2 , the solar cell module 1 includes a solar cell string 2 and a translucent protection plate 3 superimposed on the light incident side of the solar cell string 2 . Further, the solar cell module 1 is formed so as to be visible through the protective plate 3 from the sealing material 4 interposed between the solar cell string 2 and the protective plate 3 and the surface 30 of the protective plate 3 on the light incident side. , and a decorative layer 5 that reduces or blocks light in the thickness direction. Further, the solar cell module 1 includes a frame portion (frame) 6 arranged along the outer edge of the protective plate 3 , which is exposed along the outer edge of the protective plate 3 in this embodiment. The solar cell module 1 is plate-shaped, and is installed on the roof of a building such as a private house, for example, with the main surface (light receiving surface) facing upward (sun side). Moreover, in the solar cell module 1 , the decorative layer 5 is formed between the protective plate 3 and the solar cell strings 2 . In this solar cell module 1, the solar cell string 2 has power generating cells 20 that generate power by receiving light.

On the other hand, in the solar cell module 11 according to the comparative example, the decorative layer 5 is formed on the surface 30 of the protective plate 3 as shown in FIG. As a result, some of the power generation cells 20 are blocked from sunlight by the decoration layer 5 . Specifically, in the solar cell module 11 , the decoration layer 5 partially or completely blocks the incidence of sunlight in the power generating

cells

20 a and 20 b near the decoration layer 5 in plan view. When the amount of light received by the power generating

cells

20 a and 20 b whose sunlight is blocked by the decoration layer 5 decreases, the power generating

cells

20 a and 20 b become resistance within the solar cell module 11 . As a result, the amount of power generated by the power generating

cells

20c, 20d, and 20e other than the power generating

cells

20a and 20b in the solar cell module 11 is reduced, resulting in a phenomenon that the desired output cannot be secured. In this way, there is a possibility that the power generation efficiency of the entire solar cell module 11 including the

power generation cells

20c, 20d, and 20e in which the sunlight is not blocked due to the influence of the decoration layer 5 is lowered.

In contrast, according to the solar cell module 1 of the present embodiment, the decorative layer 5 is formed not on the surface 30 of the protective plate 3 but between the protective plate 3 and the solar cell string 2 in the thickness direction. Therefore, compared with the case where the decoration layer 5 is formed on the surface 30 of the protective plate 3 , the decoration layer 5 can be brought closer to the solar cell strings 2 in the thickness direction of the solar cell module 1 (vertical direction in FIG. 2 ). Therefore, by bringing the decoration layer 5 closer to the solar cell string 2 , the area of the solar cell string 2 where sunlight is shielded or attenuated by the decoration layer 5 can be reduced. Specifically, only the power generating cell 20a can be used as the power generating cell 20 in which the sunlight is blocked by the decorative layer 5 . That is, the number of power generating cells 20 whose sunlight is blocked by the decorative layer 5 can be reduced. Therefore, it is possible to suppress a decrease in the power generation efficiency of the solar cell string 2 . Since the decoration layer 5 is formed between the protective plate 3 and the solar cell strings 2 in this way, it is possible to suppress the decrease in the power generation efficiency of the solar cell strings 2, so that the decrease in the output of the solar cell module 1 can be prevented. can be suppressed.

In the solar cell string 2, each power generating cell 20 has an elongated shape, and a plurality of power generating cells 20 are single-ring connected. The shingling connection is a connection by sequentially arranging the elongated power generating cells 20 so that the long sides of the power generating cells 20 overlap with each other as if roofing a roof shingle. In addition, decoration layers 5 are formed and arranged at respective positions corresponding to both end portions in the connection direction of the solar cell string 2 related to the shingling connection.

In the solar cell string 2 in which a plurality of power generation cells 20 are connected in a single ring as described above, the single power generation cell 20 is smaller than other connection methods, and the decoration layer 5 shields sunlight or reduces light. Output is likely to drop. Therefore, in the solar cell module 1 provided with such a solar cell string 2, the decorative layer 5 can effectively take measures against output reduction. Further, even if the decoration layer 5 shields or reduces the sunlight on either side of the connection direction of the shingling connection, the decrease in output of the solar cell module 1 can be suppressed.

Furthermore, the solar cell string 2 has at least one power generation cell 20 , specifically, a plurality of power generation cells 20 . The size of each power generating cell 20 (the width dimension of each power generating cell 20 in the single-ring-connected solar cell string 2) is the same. Each power generation cell 20 has, for example, a rectangular plate shape.

The protective plate 3 is, for example, a glass plate. Moreover, the thickness of the protection plate 3 is, for example, 2 mm or more and 8 mm or less. A sealing material 4 is adhered to the protection plate 3 .

In the solar cell module 1 of this embodiment, the protective plate 3 is provided only on the surface 22 of the solar cell string 2 . In this case, the resin sheet 7 is provided on the back surface 23 of the solar cell string 2 . Protective plate 3 may be provided on both front surface 22 and rear surface 23 of solar cell string 2 .

The encapsulant 4 is, for example, superimposed on each of the front surface 22 and the back surface 23 of the solar cell string 2 . Moreover, the sealing material 4 is, for example, a resin layer. Furthermore, the sealing material 4 also covers the end faces (peripheries) of the solar cell strings 2 . Specifically, the sealing material 4 continuously covers the front surface 22 , the back surface 23 and the end surfaces of the solar cell string 2 .

The decorative layer 5 is provided to arrange the appearance of the solar cell module 1, for example, by hiding the electrical wiring around the solar cell string 2. The decorative layer 5 is, for example, a coating film formed on the rear surface 31 of the protective plate 3 opposite to the light incident side. Therefore, in the solar cell module 1 in which a general technique (coating) for improving the aesthetic appearance is used, the decorative layer 5 can be effectively used as a countermeasure against output reduction. In addition, since the coating film is formed on the rear surface 31 of the protective plate 3 , the coating film is less likely to peel off over time as compared with the structure in which the coating film is formed on the front surface 30 of the protective plate 3 .

　In the solar cell module, if the adhesive strength at the ends is not sufficient, moisture and other substances can easily enter the environment, which can lead to a loss of long-term reliability. On the other hand, in the solar cell module 1 of this embodiment, the coating film is formed so as not to contact the edge 32 of the protective plate 3 . As a result, since the coating film does not exist on the edge 32 of the protection plate 3 , the adhesive strength when bonding the protection plate 3 and the sealing material 4 together does not decrease at the edge 32 of the protection plate 3 . Therefore, even if force is applied to the edge 32 of the protective plate 3 when assembling the solar cell module 1, for example, when attaching the frame 6, the protective plate 3 and the sealing material 4 are less likely to separate. Since the ends of the solar cell module 1 are not painted, the colors differ between the ends of the solar cell module 1 and the other portions. A frame 6 can be provided so as not to overlap the decorative layer 5 (coating film). That is, the frame 6 can be attached so as to cover the portion (edge) where the coating film is not formed (so as to cover the edge of the protective plate 3), and by adjusting the color of the frame 6, A sense of unity of the entire module can be maintained.

Specifically, the decoration layer 5 is a coating film with a film thickness of 5 μm or more and 50 μm or less. Moreover, this coating film is formed by ceramic printing, for example. The decorative layer 5 is a coating film that blocks incident light or transmits (attenuates) a certain amount of incident light. In the solar cell module 1 of this embodiment, the decoration layer 5 is a black coating film, but may be a coating film of another color.

The decoration layer 5 is, for example, a coating film that fills in a predetermined range (solid coating). In the decoration layer 5, by forming a plurality of light shielding regions and a plurality of light transmitting regions adjacent to each other on the surface of the protective plate 3, light is reduced in the thickness direction by combining the light shielding regions and the light transmitting regions. It may be a coating film. Specifically, the decoration layer 5 may be a coating film in which a predetermined range is painted in a dot pattern or a mesh pattern. Moreover, the decorative layer 5 may be a light-shielding member such as a black or other color film other than the coating film. Note that the decoration layer 5 may be a part of the sealing material 4 that is colored in black or the like (a resin material mixed with a pigment, etc.). may be arranged so as to be in contact with the rear surface 31 of the .

The decorative layer 5 is arranged on the outer edge of the protective plate 3 and is a separate member from the frame portion (frame) 6 provided for shaping and reinforcing the solar cell module 1 .

Further, for example, as shown in FIGS. 4 and 5 , the solar cell string 2 is not electrically connected to any of the power generation cell 20 that generates power by receiving light and the plurality of power generation cells 20 . and dummy cells 21 that do not contribute to power generation. In this solar cell string 2, the dummy cell 21 is arranged at a position closer to the decoration layer 5 than any of the plurality of power generation cells 20 in plan view (see FIG. 4).

In the solar cell string 2, a dummy cell 21 that does not contribute to power generation is arranged in a portion where sunlight is shielded or attenuated by the decorative layer 5 (see FIG. 5). Therefore, the solar cell 20 is not affected by the shielding or dimming of the sunlight by the decorative layer 5, and the deterioration of the power generation efficiency of the solar cell string 2 can be suppressed more effectively.

In addition, in this solar cell string 2, the power generating cells 20 and the dummy cells 21 have at least the same plan view shape (see FIG. 4). In this embodiment, the thickness of the power generation cells 20 and the dummy cells 21 are substantially the same, and the color of the dummy cells 21 is also close to the color of the power generation cells 20 (see FIG. 5). As a result, the appearance of the power generation cells 20 and the dummy cells 21 can be the same through the protective plate 3 in plan view, so that the appearance of the solar cell module 1 is not spoiled even when the dummy cells 21 are arranged. Each solar cell string 2 may be composed of one power generation cell 20 and at least one dummy cell 21 .

In the solar cell module 1 described above, sample A, sample B (see FIG. 2), and sample C (see FIG. 5) were prepared, and a simulation was performed to calculate the power generation amount. In sample A, the decorative layer 5 is formed on the surface 30 of the protective plate 3 . In sample B, the decorative layer 5 is formed between the protective plate 3 and the solar cell strings 2 , and the solar cell strings 2 are all composed of power generating cells 20 . In sample C, the decorative layer 5 is formed between the protective plate 3 and the solar cell string 2, and the solar cell string 2 related to single ring connection is provided on one side in this connection direction. It is composed of power generation cells 20 . In these solar cell modules 1, the width of the power generating cells 20 is 24 mm, and the thickness of the protective plate 3 (glass plate) is 6 mm. Also, the solar cell module 1 was installed at an angle of 90 degrees and faced south. The 90-degree installation means that the solar cell module 1 is installed at an angle of 90 degrees with respect to the horizontal plane.

In this simulation, when direct light or semi-direct light is blocked by the decoration layer 5, the dummy cell 21 or the power generation cell 20 located at the extreme end on one side (sun side) in the connection direction of the solar cell string 2 is affected. Calculations were made assuming that direct light or semi-direct light is attenuated by a proportion. For the amount of solar radiation used in the simulation, the normal data for Fukuoka in the annual solar radiation amount database (METPV-11) was used.

As a result of this simulation, the annual power generation amount per 1 kW installation was 653 kWh for sample A (a sample in which the decorative layer 5 is formed on the surface 30 of the protective plate 3). The annual power generation amount was 755 kWh for sample B (a sample in which the decorative layer 5 was formed between the protective plate 3 and the solar cell string 2 and the solar cell string 2 was entirely composed of the power generating cells 20). . Furthermore, this annual power generation amount is based on the sample C (where the decorative layer 5 is formed between the protective plate 3 and the solar cell string 2 and one solar cell string 2 related to single ring connection is provided on one side in this connection direction). A sample composed of a dummy cell 21 and a plurality of power generation cells 20) was 766 kWh. As described above, the formation of the decorative layer 5 between the protective plate 3 and the solar cell string 2 resulted in an increase in the amount of power generation by approximately 16%.

It should be noted that the solar cell module of the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made without departing from the gist of the present invention. For example, the configuration of one embodiment can be added to the configuration of another embodiment, and part of the configuration of one embodiment can be replaced with the configuration of another embodiment. Furthermore, some of the configurations of certain embodiments can be deleted.

For example, the solar cell module 1 of the above embodiment is installed with the main surface (light receiving surface) side facing upward, but the present invention is not limited to this. For example, it may be attached to a vertical surface such as an outer wall of a private house or a surface close thereto (for example, a surface inclined within 15° with respect to the vertical surface). In this case, the solar cell module 1 can also be provided with a mounting portion (such as a bracket) for mounting on a vertical surface or the like. For example, the mounting portion is provided on the frame portion (frame) 6 . In the solar cell module 1 having the mounting portion, if the power generating cells 20 and the dummy cells 21 have at least the same shape in plan view, when the solar cell module 1 is installed on a vertical surface using the mounting portion, the solar cell module 1 is placed in a position that is easy to see. Even if a certain solar cell string 2 can be seen through the protective plate 3, there is no aesthetic problem.

In the solar cell string 2 of the above embodiment, the power generating cells 20 are elongated and the plurality of power generating cells 20 are single-ring connected, but this is not the only option. The shape of the power generation cell 20 may have a shape other than an elongated shape such as a square plate shape, and the plurality of power generation cells 20 may be connected by a wiring material instead of being single-ring connected.

As described above, according to the present invention, it is possible to provide a solar cell module capable of suppressing a decrease in output even when a decorative layer such as a coating film is formed so as to be visible from the surface of the protective plate (glass).

(1) A solar cell module of the present invention comprises a solar cell string having a plurality of power generating cells that generate power by receiving light; A sealing material interposed between the battery string and the protective plate, and a decorative layer that reduces or blocks light in the thickness direction and is formed so as to be visible through the protective plate from the surface of the protective plate on the light incident side. and the decorative layer is formed between the protective plate and the solar cell string in the thickness direction.

According to this configuration, the decorative layer is formed not on the surface of the protective plate, but between the protective plate and the solar cell string. Therefore, compared to the case where the decorative layer is formed on the surface of the protective plate, the decorative layer can be brought closer to the solar cell strings in the module thickness direction. The illuminated area can be made smaller. Therefore, it is possible to suppress a decrease in the power generation efficiency of the solar cell string. Since the decorative layer is formed between the protective plate and the solar cell string in this way, it is possible to suppress the reduction in the power generation efficiency of the solar cell string, thereby suppressing the decrease in the output of the solar cell module.

(2) In the solar cell module described in (1) above, the decorative layer may be a coating film formed on the back surface of the protective plate opposite to the light incident side.

According to such a configuration, in a solar cell module in which a general technique (coating) is used to enhance the aesthetic appearance, it is possible to effectively take measures against output reduction due to the decorative layer.

(3) In the solar cell module described in (2) above, the coating film may be formed so as not to come into contact with the edge of the protective plate.

According to this configuration, since the coating film does not exist on the edges of the protective plate, the adhesive strength when bonding the protective plate and the sealing material does not decrease at the edges of the protective plate.

(4) The solar cell module described in (3) above includes a frame portion exposed along an outer edge of the protective plate, and the frame portion is arranged to be exposed when the protective plate is viewed in the thickness direction. It may be provided so as not to overlap the decoration layer.

According to this configuration, even if the color tone differs between the edge portion and the other portion of the solar cell module because the coating film does not exist on the edge of the protective plate, by adjusting the color tone of the frame portion, A sense of unity of the entire module can be maintained.

(5) In the solar cell module according to any one of (1) to (4) above, the plurality of power generating cells are elongated, and the plurality of power generating cells are single-ring connected. The solar cell string may be configured, and the decorative layers may be formed and arranged at positions corresponding to both end portions in the connection direction of the solar cell string configured by the shingling connection.

According to such a configuration, in a solar cell string in which a plurality of power generation cells are single-connected, each power generation cell is small. In a solar cell module having a solar cell string with a uniform thickness, it is possible to effectively take measures against a decrease in output due to the decorative layer. In addition, even if the decorative layer shields or reduces the sunlight on either side of the shingling connection, it is possible to suppress a decrease in the output of the solar cell module.

(6) In the solar cell module according to any one of (1) to (5) above, a dummy cell that is not electrically connected to any of the plurality of power generating cells and does not contribute to power generation of the solar cell string is provided. Further, the dummy cell may be arranged at a position closer to the decoration layer than any one of the plurality of power generation cells in plan view.

According to this configuration, in the solar cell string, dummy cells that do not contribute to power generation are arranged in a portion where sunlight is shielded or attenuated by the decorative layer. It is possible to more effectively suppress the decrease in the power generation efficiency of the solar cell string due to the lower power generation cell.

DESCRIPTION OF SYMBOLS 1... Solar cell module 2... Solar cell string 3... Protection plate 4... Sealing material 5... Decoration layer 6... Frame part (frame) 7... Resin sheet 11...

Solar cell module

20, 20a , 20b, 20c, 20d, 20e... power generation cell, 21... dummy cell, 22... front side, 23... back side, 30... front side, 31... back side, 32... edge, 120, 120a, 120b, 120c, 120d, 120e... power generation cell

Claims

a solar battery string having a plurality of power generating cells that generate power by receiving light;
a translucent protective plate superimposed on the light incident side of the solar cell string;
a sealing material interposed between the solar cell string and the protective plate;
a decorative layer that reduces or blocks light in the thickness direction and is formed so as to be visible through the protective plate from the surface of the protective plate on the light incident side;
The solar cell module, wherein the decorative layer is formed between the protective plate and the solar cell string in a thickness direction.
The solar cell module according to claim 1, wherein the decorative layer is a coating film formed on the back surface of the protective plate opposite to the light incident side.
The solar cell module according to claim 2, wherein the coating film is formed so as not to come into contact with the edge of the protective plate.
A frame portion exposed and arranged along the outer edge of the protection plate,
4. The solar cell module according to claim 3, wherein said frame portion is provided so as not to overlap said decorative layer when said protection plate is viewed in the thickness direction.
The plurality of power generation cells are elongated,
The solar cell string is configured by single-ring connecting the plurality of power generation cells,
5. The solar cell module according to any one of claims 1 to 4, wherein said decorative layers are formed and arranged at respective positions corresponding to both end portions in the connection direction of said solar cell string configured by said shingling connection.
the solar cell string further includes a dummy cell that is not electrically connected to any of the plurality of power generation cells and does not contribute to power generation of the solar cell string;
2. The solar cell module according to claim 1, wherein said dummy cell is arranged at a position closer to said decoration layer than any of said plurality of power generation cells in plan view.