JPH0322572A - Solar cell - Google Patents

Abstract

PURPOSE:To sharply improve a solar cell of this design in impact resistance by a method wherein a transparent buffer layer is provided between a filler layer and a transparent weather-resistant film. CONSTITUTION:A filler layer 2 of FVA is laid on a slate tile 1, a solar cell element 3 is laid thereon, and a filler layer 2 of EVA is made to overlap, a transparent buffer layer 6 of silicone rubber or the like and PET are successively laminated thereon, and the whole laminated piece is heated at a temperature of 150 deg.C for 40 minutes or so in a vacuum of 10<-3>Torr with a laminating device, whereby the solar cell element 3 end the slate tile 1 can be formed into an integral structure. Provided that an amorphous silicon solar element formed on a glass board of 1.1<t> is used as the solar cell element 3, a silicone rubber 1mm thick is used as a buffer layer 6, a PET film 4 is formed as thick as 100mum, when an integral structure composed of these components is subjected to an impact test based on a [impact test method of building board] prescribed in JIS A 1421-1981, both the solar cell element 3 and the slate tile are hardly damaged, so that the integral structure concerned meets the requirements of JIS as a roof building materiel.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solar cell in which a solar cell element is integrated into a substrate installed on a roof.

[Conventional technology]

Conventionally, this type of solar cell has been described, for example, on pages 4-5 of the materials for the "Solar Power Generation System Symposium" held by the Japan Management Association in Tokyo from March 7, 1988 to March IO. There is a description 0 This is configured as shown in Figures 2 and 8,
In those drawings, (1) is a pentagonal asbestos slate tile as a substrate to be installed on the roof, and (2) is ethylene vinyl acetate, a transparent resin material formed on the front part of the slate tile (1). } [IEVA: packed bed consisting of l, (
3) is the solar cell element buried in the filling hole (2), (4)
is a transparent weather-resistant film made of polyethylene tere-7-talate CPET formed on the filling layer (2), (5) is a plurality of fixing screw holes transparently provided at the rear of the slate tile (1), Each slate tile (1) is fixed to the roof by screws inserted into these screw holes (5).

At this time, the front part of the slate tile (1) is sequentially superimposed on the rear part of each slate tile (1), so that each slate tile (1) is installed on the roof.

Incidentally, the PET film (4) on the top surface of which the solar cell element (3) is embedded in the filling layer (2) prevents moisture from entering from the top surface of the filling layer (2).

[Problem to be solved by the invention]

In the conventional case, the solar cell element (3) is easily broken by impact from falling objects such as electricity or stones, and JIS A 14211
Even if the slate tile (1) itself has sufficient impact resistance, the solar cell element (3) will be damaged if an impact test is conducted based on the "Impact test method for architectural boards" in 98L. , JI as a building material for roofs because it could not meet the above standards.
There is a problem that it does not conform to the S standard.

The present invention has been made with the above-mentioned points in mind, and provides a solar cell as a building material for roofs that complies with the JIS standard and prevents solar cell elements from being damaged even when subjected to an impact test based on the JIS standard. The purpose is to

[Means to solve the problem]

In order to achieve the above object, the solar cell of the present invention includes a substrate installed on a roof, a filling layer made of a transparent resin material formed on the substrate, and a solar cell element embedded in the filling layer. and a transparent buffer layer formed on the filling layer;
and a transparent weather-resistant film formed on the buffer layer.

[Effect]

In the above configuration, a transparent buffer layer is provided between the filling layer and the transparent weather-resistant film, which cushions the impact of falling objects and greatly improves impact resistance compared to conventional methods. .

〔Example〕

One embodiment will be described with reference to FIG.

In the same figure, the same symbols as in FIG. 3 indicate the same or corresponding parts, and the difference from FIG. 3 is that the EVA filling layer (
2) and the PET film (4), there is a transparent buffer layer (6) made of silicone rubber, polycarbonate resin, etc.
The point is that

At this time, the thicker the transparent buffer layer (6) is, the higher the buffering effect will be, but if it is too thick, the attenuation of the incident light will be too large.
Since the amount of light incident on the solar cell element (3) is reduced and the power generation effect is reduced, a maximum thickness of 3 mm is appropriate.

In addition, the refractive index of the transparent buffer layer (6) is the same as that of the solar cell element (3).
) is suitably between 1.8 and 1.6 so as to ensure the amount of light incident on the buffer layer (6); if the refractive index is larger than this, the reflection at the buffer layer (6) increases and the amount of incident light decreases.

The procedure for creating this solar cell is to stack the EVA forming the filling layer (2) on the slate tile (1), stack the solar cell element (3) on top of that, and then stack the EVA again.
After sequentially stacking silicone rubber, etc. and PET for the transparent buffer layer (6), these can be integrated into a laminator, a solar cell element (3), and a slate tile (1).

By the way, an amorphous silicon solar cell element formed on a glass substrate of 1.1 was used as the solar cell element (3), silicon rubber with a thickness of 1 mm was used as the buffer layer (6), and P
When the thickness of the ET film (4) was 100 μm, J Engineering S
When an impact test was conducted based on the "Impact test method for building boards" of A 1421-1981, neither the solar cell element (3) nor the slate tile (1) was damaged, and it was certified as a JIS building material for roofs. It can meet the standards.

Note that the material for the transparent buffer layer (6) is not limited to the silicone rubber or polycarbonate resin described above;
Any material that is transparent and has a buffering property of 1.6 to 1.6 may be used.

Furthermore, the materials of the filling layer (2) and the film (4) are not limited to the above-mentioned EVA and PET, respectively, and transparent resin materials such as polyvinyl butyl and polyurethane may also be used for the filling layer (2). The film (4) may be made of a waterproof material such as hollyvinyl fluorite film or St/EVA film.

Further, the substrate is not limited to the above-described asbestos slate tile, but may of course be a glass slate tile.

[Effects of the Invention] Since the present invention is configured as described above, it produces the effects described below.

Since a transparent buffer layer is provided between the filling layer and the transparent weather-resistant film, this buffer layer can reduce the impact of falling objects such as electricity, significantly improving impact resistance compared to conventional products. It is possible to provide solar cells as building materials for roofs that comply with JIS standards.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway right side view of one embodiment of the solar cell of the present invention, and FIGS. 2 and 3 are a plan view and partially cutaway right side view of a conventional example. (1)...Slate tile, (2)...Filled layer, (3)
... Solar cell element, (4) ... Transparent weather-resistant film, (6) ... Transparent buffer layer.

Claims (1)

[Claims] 1. A substrate installed on a roof, a filling layer made of a transparent resin material formed on the substrate, a solar cell element embedded in the filling layer, and a transparent buffer layer formed on the filling layer. A solar cell comprising: a transparent weather-resistant film formed on the buffer layer.