JPH0341481Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a solar cell module.

A typical solar cell module currently used industrially is one in which an upper transparent protective material, a group of solar cell elements connected by an interconnector, a thermoplastic resin encapsulant sheet, and a lower protective material are laminated. A crystalline semiconductor or an amorphous semiconductor is used as a solar cell element, and when a crystalline semiconductor is used, heat is generated between the upper transparent protective material and the solar cell element connected by an interconnector. When plastic resin encapsulant sheets are laminated and an amorphous semiconductor is used,
A configuration in which solar cell elements connected by interconnectors are formed on the surface of the upper transparent protective material, or solar cell elements connected by interconnectors are formed on the surface of an opaque substrate such as a stainless steel substrate, and this solar cell element forming surface and A configuration in which a thermoplastic resin encapsulant sheet is laminated between the upper transparent protective material and the upper transparent protective material is generally adopted.

In a solar cell module having such a configuration, a fluororesin sheet/metal foil/fluororesin sheet laminated sheet is generally used as the lower protective material. Fluororesin sheets are suitable materials because they have excellent weather resistance and heat resistance, and the sheets usually contain a white inorganic filler to increase the efficiency of reflecting incident light. There are many cases. Further, the metal foil has a moisture-proofing effect that prevents moisture from entering from the lower surface side of the module.

However, a drawback of the solar cell module having the above structure, especially its lower protective material, is that its manufacturing cost is extremely high. The reason for this is that two expensive fluororesin sheets are used, and dry lamination has to be performed in two steps in order to bond these two sheets to both sides of the metal foil. . Therefore,
If the fluororesin sheet is made thinner in order to reduce its manufacturing cost, the withstand voltage of the sheet layer decreases, causing a serious defect such as a short circuit between the semiconductor and its connector and the metal foil. In addition, fluororesin is generally difficult to form into sheets, and plasticizers are used to improve its formability. However, when such sheets are used to heat-laminate solar cell modules, Due to chemical vapor and moisture, good adhesion cannot be formed between the sealant and the sealant sheet.

As a result of intensive studies to solve this problem, the inventors of the present invention have now discovered that the fluororesin sheet and metal foil in contact with the thermoplastic resin encapsulant sheet can be replaced with a vinylidene chloride resin sheet. .

Therefore, the present invention relates to a solar cell module,
This solar cell module consists of an upper transparent protective material, a group of solar cell elements connected with interconnectors,
In a solar cell module formed by laminating a thermoplastic resin encapsulant sheet and a lower protective material, the lower protective material is composed of a vinylidene chloride resin sheet/fluororesin sheet laminated sheet, and the fluororesin sheet faces the outside of the module. It is arranged so that

FIG. 1 of the drawings is a sectional view of a solar cell module using crystalline silicon as a solar cell element.

Upper transparent protective material (approximately 0.01 to 5 mm thick) 1 includes:
In order to increase the transmission efficiency of incident light, a sheet of transparent glass or transparent polyvinyl fluoride, fluororesin such as poly(chlorotrifluoroethylene), acrylic resin, weather-resistant polyester resin, polyimide resin, or the like is used. Below, crystalline silicon solar cells connected with a thermoplastic resin encapsulant sheet (approximately 0.1 to 2 mm thick) such as ethylene-vinyl acetate copolymer resin (approximately 0.1 to 2 mm thick) 2 and an interconnector (approximately 0.01 to 0.5 mm thick) 3 Element (thickness approx. 0.01~1
mm) 4 groups and a thermoplastic resin encapsulant sheet 5 (thickness approximately 0.02 to 2 mm) are sequentially laminated.

These thermoplastic resin encapsulant sheets 2 and 5
Examples include ethylene-vinyl acetate copolymer resin, ethylene-(meth)acrylate copolymer resin, polyvinyl butyral resin (degree of butyralization around 65 mol%, containing triethylene glycol di-2-ethyl butyrate plasticizer), etc. A sheet of thermoplastic resin is used. In the case of a copolymer resin sheet, it may be a sheet of silane-modified resin or organic peroxide-containing resin, and in the case of the latter sheet, it is modified into a crosslinked structure in the bonding process. These sealant sheet materials may also contain plasticizers, weather stabilizers, ultraviolet absorbers, antioxidants, adhesion promoters, dyes, pigments, and the like, if necessary.

In addition, about 0.5 to 10% of a white inorganic filler such as calcium carbonate or titanium oxide is added to the encapsulant sheet 5.
Preferably, the content of about 2 to 3% is advantageous because it can reflect incident sunlight and improve the energy conversion efficiency of the solar cell.

A lower protective material is laminated next to such a sealing material sheet. The lower protective material 6 is made of a laminated sheet of vinylidene chloride resin sheet 7/fluororesin sheet 8. A laminated sheet made of such a two-layer material is
Although they can be used in a pre-laminated form, it is only necessary that when laminated on a solar cell module, the lower protective material is eventually composed of these two-layer materials.

As a vinylidene chloride resin sheet, the thickness is approx.
A material with a diameter of about 0.005 to 0.1 mm is used. In addition, as a fluororesin sheet, the thickness is approximately 0.01 to 0.2 mm.
The sheet may contain an inorganic pigment such as titanium oxide, if necessary.

Lamination of each of the base materials described above involves first laminating some of the base materials in advance using a dry lamination method, etc., and then stacking them one after another. If necessary, organic silane or acrylic is applied to the adhesive surface of each base material. This is done by applying a urethane-based adhesive or a urethane-based adhesive, and pressing and heating it with a vacuum heating laminator. In this case, a cross-linked moldable resin may be placed in a part of the space between the solar cell elements that are not in a direct connection relationship, and the resin may be press-heated so that a short circuit is not formed between the solar cell elements due to the press-heating.

Further, FIG. 2 is a cross-sectional view of a solar cell module in which amorphous silicon formed on a transparent substrate is used as a solar cell element. In this embodiment, a group of amorphous silicon solar cell elements 4' connected by interconnectors 3' are vacuum-deposited on the surface of an upper transparent protective material 1 such as a glass substrate.
It is formed by means such as sintering and printing.

According to the present invention, by replacing one of the fluororesin sheets constituting the lower protective material with an inexpensive vinylidene chloride resin sheet with low moisture permeability, it is possible to reduce the manufacturing cost by eliminating the use of metal foil. Not only can this be achieved, but also the absence of metal foil naturally eliminates phenomena such as short circuits between the metal foil and the solar cell element or its connector, and reductions in withstand voltage. Moreover, when a solar cell module is heat laminated using a vinylidene chloride resin sheet, there is also an advantage that better adhesion is formed between the resin sheet and the encapsulant sheet 5.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a solar cell module using a crystalline semiconductor as a solar cell element. Further, FIG. 2 is a cross-sectional view of a solar cell module in which an amorphous semiconductor formed on a transparent substrate is used as a solar cell element. Explanation of symbols, 1...Top transparent protective material, 3, 3'
...Interconnector, 4,4'...Solar cell element, 5...Thermoplastic resin encapsulant sheet, 6...
Lower protective material laminated sheet, 7... Vinylidene chloride resin sheet, 8... Fluorine resin sheet.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. In a solar cell module formed by laminating an upper transparent protective material, a group of solar cell elements connected by an interconnector, a thermoplastic resin encapsulant sheet, and a lower protective material, the lower protective material is A solar cell module comprising a vinylidene chloride resin sheet/fluororesin sheet laminated sheet, the fluororesin sheet being arranged so as to face the outside of the module. 2 Utility model registration claim Paragraph 1, in which the solar cell element is made of a crystalline semiconductor, and a thermoplastic resin encapsulant sheet is laminated between the upper transparent protective material and the solar cell element connected by an interconnector. The solar cell module described. 3. The solar cell module according to claim 1, wherein the solar cell elements are made of an amorphous semiconductor, and the solar cell elements connected by interconnectors are formed on the surface of the upper transparent protective material. 4. The solar cell element is made of an amorphous semiconductor, and the solar cell element connected by an interconnector is formed on an opaque substrate surface, and a thermoplastic resin sealing material is placed between the solar cell element forming surface and the upper transparent protective material. The solar cell module according to claim 1 of the utility model registration claim, which comprises laminated sheets. 5. The solar cell module according to claim 1, wherein the thermoplastic resin encapsulant sheet is formed from an ethylene-vinyl acetate copolymer resin. 6. The solar cell module according to claim 1, wherein the thermoplastic resin encapsulant sheet is made of polyvinyl butyral resin. 7. The solar cell module according to claim 1, 5, or 6, wherein the thermoplastic resin encapsulant sheet contains a white inorganic filler.