JPH02177573A - Photovoltaic device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Industrial applications The present invention relates to photovoltaic devices, particularly solar cells.

Solar cells are currently widely used as an energy alternative to petroleum and in electronic devices such as calculators that require a small amount of electricity.

In this context, attempts are being made worldwide to create low-cost solar cells. Among these, some that use compound semiconductors and amorphous silicon are currently in practical use.
These devices often have a structure in which a thin film is formed on a transparent substrate such as glass, or a structure in which a thin film is formed on a conductive substrate such as stainless steel.

Conventional thin film type electromotive force devices use a thin semiconductor film, so it is very difficult to create a film with a uniform color. Therefore, when commercializing a product, it is recommended to make the transparent glass that serves as the light-receiving surface frosted glass, or to place a thin cover sheet on top of the transparent glass to make the non-uniformity of color difficult to notice visually.
was taken.

Problems to be Solved by the Invention Processing the transparent glass of the light-receiving surface into frosted glass is expensive and increases physiological costs.

In addition, frosted glass is difficult to cut, making it difficult to create photovoltaic devices on a large-area substrate and then cut and divide them into required dimensions to create large quantities of small-area photovoltaic devices at once. be.

Another method is to place a thin cover sheet on transparent glass, but this method has the problem of reducing the amount of light incident on the photovoltaic device.

Means for Solving the Problems The present invention was made to solve these problems, and a resin containing two particulate inorganic substances is applied to the light-receiving surface glass of a photovoltaic device to form a frosted glass-like structure. By adopting the external structure, color unevenness on the surface of the photovoltaic device can be made visible from the outside without reducing the amount of light incident on the photovoltaic device.

By applying a resin containing a granular inorganic substance to the transparent glass surface of a photovoltaic device and drying and curing the resin, the transparent glass surface has a milky-white frosted glass appearance. The light scattering effect of the granular inorganic material makes it difficult to see color unevenness on the surface of the photovoltaic device, improving its commercial value.

Since the refractive index of the resin applied to the transparent glass surface is in the intermediate range between that of air and glass, it also has the effect of reducing reflection loss of incident light on the surface of the photovoltaic device and improving the characteristics of the photovoltaic device. .

Since the resin used in the present invention can be screen printed, it is possible to print on a large area substrate leaving only the glass cutting line.

Therefore, when creating a large number of solar cells by dividing a large-area solar cell into small parts, the present invention has the advantage that resin printing can be performed without coating only the cutting line with resin, and cutting and division can be easily performed. .

Example FIG. 1 shows a photovoltaic device according to an embodiment of the present invention.

In the figure, 1 is coating resin, 2 is transparent glass plate, 3 is C
dS film, 4 a CdTe film, 5 a carbon film, and 6 a mug electrode.

The manufacturing method is to form a CdS film 3 on a transparent glass plate 2, and further form a CdTe film 4 thereon.

A carbon film 6 is formed on the CdTe film 4, and mug electrodes 6 are formed on each of the carbon film 6 and the CaS film 3 to form a photovoltaic device. Thereafter, a resin paste is applied onto the transparent glass plate 2 and dried to form the coating resin 1.

This resin contains a particulate material having a light scattering effect such as silica or titanium oxide. By including such a particulate material, the light scattering effect gives the product a frosted glass appearance, thereby eliminating defects in the commercialization of photovoltaic devices, such as color unevenness. Further, due to the effect of the particulate matter, the surface of the coated resin becomes uneven and has the effect of promoting a frosted glass appearance. The amount of the granular material added is preferably in the range of 6 to 50 yen based on the total weight of the resin.

In addition to CdS, the CdS film 3 may contain a small amount of a flux such as C (!C12) or an inorganic compound to improve voltage characteristics and crystallinity. Additives may be included for this reason.

The type of resin used for the coating resin film 1 is preferably an epoxy resin, a fluorine resin, or an acrylic resin. Urethane-based, polycarbonate-based, and vinyl chloride-based materials are also possible. Generally, the refractive index of the resin is in the intermediate range between the refractive index of glass and the refractive index of air, so by coating it on the transparent glass 2, it is possible to reduce the reflection loss of incident light on the glass surface.

The thickness of the resin film 1 is preferably in the range of 1 μm to 500 μm. If it is less than 1 μm, the mechanical strength of the resin itself decreases, and the frosted glass effect also decreases, so the effect of the overcoat resin coating decreases. Moreover, if it is 500 μm or more, the amount of transmitted light decreases, and the output of the solar cell element decreases.

FIG. 2 shows a plan view of a photovoltaic device in which resin is printed in a prescribed pattern on the light-receiving surface of the photovoltaic device.

In Figure 2, 1 is the coating resin and 7 is the cutting line.

8 is a light receiving surface of the photovoltaic device. Small-sized photovoltaic devices currently on the market are created by subdividing a large-area photovoltaic device into predetermined sizes.

If resin is applied on the cutting line, the glass cutter will not be able to make the cut, causing cutting problems.

Therefore, as shown in FIG. 2, it is necessary to apply resin to the area excluding the parting line.

Effect of the invention According to the present invention, the following effects can be obtained.

(1) The surface of the photovoltaic device becomes frosted glass, which has the effect of eliminating external defects such as color unevenness of the photovoltaic device, and increases the commercial value.

(2) Compared to the case where the surface of the transparent glass plate that serves as the light-receiving surface of the photovoltaic device is treated with frosted glass, the processing cost is lower, and the refractive index of the resin itself is in the intermediate range between that of glass and air; Light reflection loss at the light-receiving surface is reduced, and the characteristics of the photovoltaic device are improved.

(3) When cutting a large-area photovoltaic device into parts to create a large number of small-area photovoltaic devices, glass cutting is difficult if frosted glass processing is performed.

In the case of resin coating, if the resin is not applied only on the cutting line, the glass plate can be cut and divided as desired. Therefore, it is very convenient for manufacturing a photovoltaic device in a large area and dividing it into smaller areas to produce products.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional structural diagram of a photovoltaic device according to the present invention, and FIG.
The figure is a plan view when resin is applied in a prescribed pattern size onto the light receiving surface of a photovoltaic device according to the present invention. 1...Coating resin, 2...Transparent glass plate, 3...CdS film layer, 4...
CdTe film layer, 6...Carbon film, 6...
- Mug electrode.

Claims (5)

[Claims] (1) A photovoltaic device characterized in that a resin containing a granular inorganic substance is coated on the light receiving surface of the photovoltaic device to give the light receiving surface a frosted glass appearance. (2) The photovoltaic device is made of transparent glass on which two compound semiconductor layers, an electrode layer and a resin film are formed, and the two compound semiconductor layers are cadmium sulfide or a compound semiconductor containing sulfur or cadmium, and cadmium telluride. The photovoltaic device according to claim 1, wherein the photovoltaic device is a compound semiconductor containing tellurium or cadmium, and the transparent glass is located on the light-receiving surface side. (3) The photovoltaic device according to claim 1, wherein the particulate inorganic substance contains at least one of silica and titanium oxide, and has a total content of 50% or less of the weight of the resin. (4) The photovoltaic device according to claim 1, wherein the resin film thickness is 1 μ to 500 μ. (5) The photovoltaic device according to claim 1, wherein the resin is applied in a prescribed pattern on the light-receiving surface of the photovoltaic device.