JP3363367B2 - Cover glass structure for solar cell module - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cover glass structure for a solar cell module which is installed on a rooftop of a house or the like and is flexible, moisture-proof and has long-term reliability.

[0002]

2. Description of the Related Art Currently, from the standpoint of environmental protection, research and development of clean energy is in progress. Among them, solar cells have been attracting the most attention because of their unlimited resources (sunlight) and no pollution. In particular, amorphous silicon solar cells are thin and lightweight, have low manufacturing costs,
It is expected that it will become the mainstream of solar cells in the future because it is easy to increase the area. Conventional solar cells use a glass substrate, but from the viewpoints of weight reduction, workability, mass productivity, etc., research and development of flexible type solar cells using a plastic film or a metal film are underway. As a result, mass production is possible by the roll-to-roll manufacturing method that makes the most of flexibility.

FIG. 9 shows a conventional example of a solar cell module. 9A is a plan view, and FIG. 9B is a sectional view taken along line XX ′. That is, the first electrode layer 8 is sequentially formed on the long film substrate 7 made of an insulating and flexible resin.
The photoelectric conversion layer 9 and the second electrode layer 10 are laminated, and these are sandwiched by the moisture-proof film 12 via the adhesive layer 11. In addition, 8a is a back surface electrode layer formed on the back surface side of the substrate 7,
It is used for collecting current in individual solar cell elements that constitute a module and for connecting between the elements. The photoelectric conversion layer 9 is, for example, a pin junction of amorphous silicon. Materials for film substrates include polyimide,
Films of polyetherimide, para-aramid, and fluororesin are generally used.

As the adhesive layer, an ethylene-vinyl acetate copolymer (hereinafter abbreviated as EVA), a vinyl chloride copolymer or polyvinyl alcohol (hereinafter abbreviated as PVA), polyvinyl butyral (hereinafter also abbreviated as PVB). Are used. As the moisture-proof film, films made of fluororesin, polymethylmethacrylate, polysulfone, polyethersulfone, polyvinyl chloride, polycarbonate and the like are used. When the solar cell module is installed and used on the roof of a house or the like, it is obliged to cover the upper part of the module with an incombustible material (glass) or the like. Therefore, conventionally, as shown in FIG. 10, for example, the glass 1 is used for each sheet to cover the solar cell module.

[0005]

In FIG. 10, the cover glass 1 is configured to be inserted along the support rails 3 installed on a rooftop or the like. It may crack or break. Although tempered glass is usually used as the glass 1, this is because it has the property of being strong against the force in the plane direction but weak against the force in the lateral direction. In addition, the method of FIG. 10 has a drawback that a gap is likely to be formed between the glasses, and rainwater, dust and the like are likely to enter. Therefore, an object of the present invention is to provide a cover glass structure in a solar cell module, which has relatively high mechanical strength, makes it difficult for rainwater and dust to enter, and additionally enables protection from ultraviolet rays and infrared rays. It is in.

[0006]

In order to solve such a problem, in the invention of claim 1, the flexible substrate on which the photoelectric conversion element layer is formed is sandwiched and sealed by a moisture-proof film via an adhesive layer. In the cover glass structure for covering the light receiving surface of the solar cell module, the cover glass is formed by stacking and bonding two pieces of glass in a stepwise manner with a resin sandwiched between them, and attaching the glass to the side surface of the cover glass.
Guide plate, cover glass and guide
Rubber sheet or plastic is inserted between
It is characterized by that. According to the first aspect of the invention, when the cover glasses are combined with each other, they are aligned with each other.
The blank area of the eyes can be sealed with resin or non-drying oil (the invention of claim 2). In the invention of claim 1 or 2,
The exposed part of one end of the cover glass is covered on the entire surface of one side.
The oil can be adhered (the invention of claim 3).

In the invention of any one of claims 1 to 3 , an ultraviolet absorber can be mixed with the resin (invention of claim 4). In the invention of any one of claims 1 to 4 , the infrared cut film can be sandwiched between the resins (the invention of claim 5).

[0008]

[Embodiment Referring Figure 1 the embodiment of the present invention
It is a reference diagram for explaining a relationship . 1 (a) is a perspective view showing a cover glass, FIG. 1 (b) is a sectional view taken along the line XX ', FIG. 1 (c) is a perspective view showing an example in which the cover glass is inserted into a rail, and FIG. The YY 'cross-sectional view, the same (e) shows the ZZ' cross-sectional view and the installation method on the roof, respectively. The roof has a structure in which a field board 14 is placed on a rafter 15, and the rail 3 is installed on this field board. The solar cell module 13 is directly installed on the field board between the rails. These points are the same for FIGS. 2 to 5. In the present invention, the cover glass installed on the solar cell module, in this case two pieces of glass 1 is made of resin 2
It is configured by laminating in different steps.

As the glass, tempered glass having a thickness of about 3 mm is used. As the amount of step difference, L1 = 3 to 5c when the length of the entire glass is approximately L = 60 cm.
It is about m. The resin 2 is made of acrylic or vinyl acetate having a thickness of about 0.3 to 0.5 mm.
The bonding is performed by interposing the resin 2 between the two sheets of glass, and holding and bonding them with a vacuum laminator at 150 ° C. for 15 minutes. By doing so, the number of parts that come into contact when the glasses are combined as shown in FIGS. 1C and 1D is increased, so that the mechanical strength is increased and damage can be prevented. It was also possible to prevent rainwater and dust from entering.

FIG. 2 illustrates the relationship with the embodiment of the present invention .
It is another reference drawing for clarifying. This is a rail 3 installed at a predetermined position such as a roof on the cover glass shown in FIG.
It is characterized in that guide plates 4 are provided at both ends in contact with, and other points are the same as in FIG. As a result, the cover glass can be prevented from being directly contacted with the rail 3 and damaged, the cover glass can be easily attached and detached, and the entry of dust can be suppressed. Although aluminum is assumed as the material of the rail 3, aluminum alloy, stainless steel, plastic, or the like can be used. At this time, it is desirable to perform processing such as polishing so that the contact surface of the rail 3 with the cover glass has an appropriate smoothness.

FIG. 3 is a structural diagram showing a first embodiment of the present invention. This is characterized in that a rubber sheet 5 is inserted between the cover glass and the rail 3 for guiding the cover glass as compared with the one shown in FIG. This can prevent rainwater and dust from entering. As the rubber material, for example, all rubbers including ethylene-propylene-diene rubber (also abbreviated as EDPM) can be used, and in some cases, plastic can also be used. Further, although the present embodiment is applied to the one shown in FIG. 2, it goes without saying that the same can be applied to the one shown in FIG.

FIG. 4 is a structural diagram showing a second embodiment of the present invention. This is because in order to prevent rainwater from intruding from the fitting portion of the cover glasses, the fitting blank portion (see (d) of FIGS. 1 to 3) is provided with the portion of FIG.
As described above, the natural oil or fat or the transparent resin 6 is injected. Natural oils and fats include non-drying oils such as olive oil and peanut oil. The resin may be any transparent one. It should be noted that although it is applied here to the one shown in FIG. 3, it can be applied to those shown in FIGS. 1 and 2 in the same manner.

FIG. 5 shows a modification of FIG. This is
As is apparent from (b), the resin is adhered to the entire one surface of the exposed portion at one end of the cover glass.
This eliminates the need for sealing as shown in FIG. 4 when the cover glasses are combined with each other, and increases the strength as compared with that shown in FIG. 1, so that the risk of breakage can be further reduced. Although the example in which the guide plate 4 and the rubber sheet 5 are added is shown here, it is needless to say that one or both of them may be omitted to configure as shown in FIG. 1 or 2.

By the way, ultraviolet rays from sunlight have a high energy and have a property of easily decomposing things. Therefore, in the solar cell module as well, the ultraviolet rays should not reach the adhesive layer 11 as much as possible. Is desirable. Therefore, in the present invention, an ultraviolet absorber is mixed in the resin 3 constituting the cover glass in an amount of about 1% by weight. FIG. 6 shows the light transmittances of the glass alone (the former) and the cover glass structure of the present invention (the latter) bonded with a resin containing an ultraviolet absorber. From this figure, it is understood that the latter does not transmit light of 300 to 350 nm on the short wavelength side. That is, by adopting the latter method, it is possible to block the ultraviolet rays that cause deterioration and ensure long-term reliability.

It has been pointed out that the efficiency of the solar cell module decreases when it is operated at a high temperature. In other words, when infrared rays hit the solar cell module, the temperature rises and its efficiency decreases. Therefore, in the present invention, for example, a polyethylene terephthalate (also abbreviated as PET) film 2A coated with, for example, an infrared reflecting agent of about 100 μm
Were sandwiched by the resin 2 as shown in FIG.
FIG. 8 shows the light transmittance and reflectance of a PET film alone (the former) and a PET film coated with an infrared reflecting agent (the latter). From this figure, in the wavelength range of 800 nm or more, it is 20%, which is twice as much as when the infrared reflecting agent is not applied.
You can see that it has been cut (see dotted line with black circle). In other words, the latter method improves the heat insulation effect and ensures long-term reliability. This example can also be applied to the above-described resin in which an ultraviolet absorber is mixed.

[0016]

According to the present invention, since the cover glass installed on the solar cell module has a structure in which two sheets of glass are attached in a stepped manner by a resin here, mechanical strength is improved. Is increased, the rate of damage is reduced, and it is possible to prevent rainwater and dust from entering. Also,
It is possible to prevent deterioration of the solar cell module and to secure long-term reliability when it is installed outdoors by mixing the resin with ultraviolet absorption to block ultraviolet rays or by using an infrared reflection film.

[Brief description of drawings]

FIG. 1 is a reference diagram for explaining a relationship with an embodiment of the present invention.

FIG. 2 is another reference diagram for explaining the relationship with the embodiment of the present invention.

FIG. 3 is a structural diagram showing a first embodiment of the present invention.

FIG. 4 is a structural diagram showing a second embodiment of the present invention.

FIG. 5 is a structural diagram for explaining a modification example of FIG.

FIG. 6 is an explanatory view of light transmittance of glass sandwiching a glass simple substance and a resin to which an ultraviolet absorber is added.

FIG. 7 is an explanatory view of a structure in which a film in which an infrared reflecting agent is applied to resin is sandwiched.

FIG. 8 is an explanatory diagram of light transmittance and reflectance of the infrared reflecting agent.

FIG. 9 is a structural diagram showing a conventional example of a solar cell module.

FIG. 10 is a structural diagram showing a conventional example of a cover glass for a solar cell module.

[Explanation of symbols]

1 ... Glass, 2 ... Resin, 2A ... Infrared reflector coated PET
Film, 3 ... Rail, 4 ... Guide plate, 5 ... Rubber sheet, 6 ... Non-drying oil, 7 ... Film substrate, 8 ... First electrode layer, 9 ... Photoelectric conversion layer, 10 ... Second electrode layer, 11 ... Adhesion Layer, 12 ... Moisture-proof film, 13 ... Solar cell module,
14 ... Field board, 15 ... Rafter.

─────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-9-279792 (JP, A) JP-A-9-32206 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H01L 31/04-31/078 E04D 13/00-13/18

Claims (5)

(57) [Claims] 1. A cover glass structure in which a flexible substrate on which a photoelectric conversion element layer is formed covers a light-receiving surface of a solar cell module sandwiched and sealed by a moisture-proof film via an adhesive layer, wherein two cover glasses are provided. The glass of the above is sandwiched between resin layers and stacked and bonded in different steps.
Install the guide plate on the side of the
Rubber sheet or plus between the rail to guide this
A cover glass structure for a solar cell module, in which a tick is inserted . 2. The cover glasses are combined together.
When using a resin or non-drying oil
The cover glass structure for a solar cell module according to claim 1, which is sealed . 3. An exposed portion of one end of the cover glass
A resin is adhered to the entire surface of one side.
Alternatively, the cover glass structure for a solar cell module described in 2. 4. The cover glass structure for a solar cell module according to claim 1, wherein an ultraviolet absorbent is mixed with the resin . 5. An infrared cut film is sandwiched between the resins.
Claims 1, characterized in a way to push seen to cover glass structure for a solar cell module according to any one of 4.