KR20180114319A - Patterning glass for solar panel module and solar panel module including same - Google Patents

Abstract

One embodiment of the present invention relates to a cover glass for a photovoltaic cell module. A pattern of a concavo-convex structure regularly arranged on a first surface of a cover glass is formed. The concavo-convex structure exhibits an effect of a concave lens and diffuses light transmitted through the first surface of the cover glass. Moreover, according to another embodiment of the present invention, the photovoltaic cell module includes a substrate, a photovoltaic cell formed on the substrate, an encapsulation material surrounding the substrate and the photovoltaic cell, a backsheet formed on one surface of the encapsulation material, and a cover glass formed on the other surface of the encapsulation material.

Description

[0001] The present invention relates to a patterning glass for a solar cell module and a solar cell module including the patterning glass,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a patterning glass for a solar cell module and a solar cell module including the same. More particularly, the present invention relates to a cover glass having a regular pattern formed therein to improve transmittance and haze.

Recently, the exhaustion of fossil energy resources such as petroleum and coal is rapidly progressing, and as the limit is predicted, there is an increasing interest in energy that can replace them, especially environment-friendly energy. Among them, solar cells using solar energy are particularly attracting attention because of their abundant energy resources and lack of environmental pollution. Solar cells include solar cells that generate the steam needed to rotate the turbine using solar heat, and solar cells that convert sunlight into electrical energy using the properties of semiconductors. However, a solar cell generally refers to a solar cell (hereinafter referred to as a solar cell).

A solar cell has a junction structure of a p-type semiconductor and an n-type semiconductor like a diode. When light is incident on the solar cell, electrons and electrons with negative charge are generated by the interaction with light and the material constituting the semiconductor of the solar cell, and positive holes are generated, and the current flows while they move. This is called the photovoltaic effect. The electrons in the p-type and n-type semiconductors constituting the solar cell are attracted toward the n-type semiconductor and the holes are attracted toward the p-type semiconductor to move to the n-type semiconductor and the p- When these electrodes are connected by a wire, electric power can be obtained because electricity flows.

A cover glass for protecting the solar cell module from external impact or environment is provided on the solar cell module having the solar cell array. As a constitution of the solar cell module, the cover glass influences the power generation efficiency in the solar cell module depending on the transmittance in transmitting sunlight.

In order to improve the transmittance of the cover glass, a technique for controlling the composition ratio of the cover glass material has been proposed. Of these technologies, attention has been paid to techniques for minimizing the internal absorption rate and techniques for minimizing the reflectance by coating a low reflection material on the cover glass.

However, these techniques also fail to provide additional power generation efficiency to the solar cell because of the low optical efficiency in the cover glass of the solar cell module. Therefore, there is a demand for research on a solar cell module capable of improving light transmittance and haze of a cover glass by allowing light absorption by a solar cell module using a cover glass.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a cover glass for a solar cell module and a solar cell module including the same that minimize the reflectance of light transmitted through a cover glass and improve transmittance and haze.

A cover glass for a solar cell module according to an embodiment of the present invention is characterized in that a concavo-convex structure pattern is regularly arranged on a first surface of a cover glass, and the convexo-concave structure exhibits the effect of a concave lens, Is a cover glass for a solar cell module that diffuses light transmitted through a surface.

In one embodiment, the pattern comprises a plurality of regularly arranged polygonal or circular concave-convex structures.

In one embodiment, the pattern is a honeycomb structure.

In one embodiment, the light transmitted through the first surface of the cover glass is reflected by the second surface of the cover glass and then travels toward the first surface, and the path changes in the first surface.

In one embodiment, the average depth of the irregularities is 600 nm to 2.1 占 퐉.

A solar cell module according to another embodiment of the present invention includes a substrate, a solar cell formed on the substrate, an encapsulant surrounding the substrate and the solar cell, a backsheet formed on one surface of the encapsulant, Wherein the concave and convex structure exhibits the effect of the concave lens, and the concave and convex structure has a concave and convex structure, and the concave and convex structure has a concave- .

According to the present invention, the patterning treatment is performed on one surface of the cover glass to minimize the reflectance of light toward the cover glass and to maximize the transmittance.

In addition, the haze of the cover glass can be improved.

Thus, the power generation efficiency in the solar cell module can be improved.

FIG. 1 is a graph showing the voltage versus short-circuit current density according to presence or absence of a cover glass.
FIG. 2 is a graph showing spectral response characteristics (EQE) versus wavelength depending on the presence or absence of a cover glass.
FIG. 3 is a graph showing spectral response characteristics versus wavelength for bare glass, random textured glass, and honeycomb textured glass. FIG.
Figure 4 is an image of the surface of a random textured glass.
Figure 5 is an image of the surface of a honeycomb textured glass.
FIG. 6 is a graph showing the spectral response characteristics of the honeycomb-textured glass with respect to the wavelength of the concavo-convex structure having various depths according to various etching methods.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the term " comprises " or " having " is intended to designate the presence of stated features, elements, etc., and not one or more other features, It does not mean that there is none.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

The cover glass for a solar cell module according to an embodiment of the present invention is characterized in that a concavo-convex structure pattern is regularly arranged on a first surface of the cover glass, and the convexo-concave structure exhibits the effect of a concave lens, It is possible to diffuse light transmitted through the first surface of the light guide plate.

In other words, it is possible to improve the power generation efficiency of a solar cell module by applying a cover glass having a transmittance improved to absorb solar light by a solar module by forming a structural pattern capable of minimizing reflection on the top of the cover glass To improve PV modules

Here, the pattern may include a plurality of regularly arranged polygonal or circular concave-convex structures. Furthermore, the pattern may be a honeycomb structure. Through this, the light transmitted through the first surface of the cover glass is reflected by the second surface of the cover glass and then travels toward the first surface, and the path can be changed in the first surface.

Here, the average depth of the concavities and convexities may be 600 nm to 2.1 占 퐉.

That is, the cover glass for a solar cell module of the present invention includes an array pattern having a predetermined size on the first surface, and the concavo-convex structure produces the same effect as the concave lens. Therefore, It happens. However, a part of the sunlight where no diffusion occurs is expected to cause optical loss due to reflection. After the reflected light is reflected again on the second surface, the optical path can again be changed through the first surface, thereby allowing the lost light to be recycled.

A glass having such a characteristic can be used as a cover glass of a solar cell module. That is, a solar cell module including such a glass includes a substrate, a solar cell formed on the substrate, a sealing material surrounding the substrate and the solar cell, a backsheet formed on one surface of the sealing material, And a cover glass formed on the other surface of the encapsulating material.

The concave-convex structure of the cover glass has a concave-convex structure that is regularly arranged on one surface. The convex-concave structure exhibits the effect of the concave lens and can diffuse the light transmitted through the first side of the cover glass.

Here, the pattern may include a plurality of regularly arranged polygonal or circular concave-convex structures. Furthermore, the pattern may be a honeycomb structure. Through this, the light transmitted through the first surface of the cover glass is reflected by the second surface of the cover glass and then travels toward the first surface, and the path can be changed in the first surface. Here, the average depth of the concavities and convexities may be 600 nm to 2.1 占 퐉.

The components not specifically described in the constituent elements of the solar cell module of the present invention are not particularly limited in the present invention and, unless the scope of the present invention is specifically limited, Element can be applied.

Furthermore, any component not included as an element of the present invention can be added as long as the scope of the present invention is not specifically limited.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments of the present invention.

Experiments were carried out according to the following procedure, and the results of the fms test are shown in the drawing according to the characteristics of each cover glass.

First, a glass substrate sample was processed by a standard cleaning process (RCA). The generated water was removed using nitrogen gas. Then, it was dried in a heating oven at 100 ° C for 10 to 30 minutes. This is to use a photoresist (PR), aluminum (Al), silicon nitride (SiNx), amorphous silicon (a-Si) or the like as a hard mask on a glass substrate.

After completion of the drying process, a hard mask was deposited using a photoresist. This is because it has the effect of reducing the process step than using the conventional Al, SiNx, and a-Si. Hexamethyldisilazane (HMDS) was applied by using a spin coater to improve the adhesion between the glass substrate and the photoresist before coating the photoresist on the glass substrate.

Approximately 2 ml of HMDS was sprayed on to the spin coater, and the velocity was in the range of 500 to 3000 rpm for 40 seconds. Then, drying was carried out on a hot plate at a temperature range of 130 to 150 ° C for 3 minutes. Again, the photoresist was sprayed on the spin coater and processed at 5000 rpm for 30 seconds and dried in a dry oven at a temperature of 110 DEG C for 10 minutes.

When the photoresist process was completed, the sample was placed on a mask and photoresist-coated surface in a photolithography room and patterned by UV exposure. The patterned sample was dried in a dry oven at a temperature of 140 ° C for 15 minutes by using the pattern, and the glass was etched with a solution of hydrofluoric acid. The etched glass is finally subjected to the cleaning process in the RCA process and the process is completed in the dry oven.

A module was fabricated using the completed substrate and the prepared crystal system or heterojunction solar cell. The process used here is a commonly used process, the order of which is as follows.

The metal ribbon was bonded to the front part of the solar cell and the unit process inspection was carried out. Here, the unit process inspection refers to confirming the I-V characteristics of the solar cell. Then, an encapsulant called EVA Sheet was placed on both sides, a back sheet was attached to the rear portion, and a cover glass was formed on the front portion. The lamination process was carried out on it, and it was intended to protect it from various environmental factors generated from the outside, and the unit process test was similarly performed. Finally, an aluminum frame was installed and the junction box was not installed separately.

In order to confirm the conversion efficiency characteristics of the solar cell module, the optical capture glass structure of the front part was varied.

First, an experiment was conducted to use bare glass (no shape on the glass substrate) as a control group.

In order to obtain the control reference in the 1-cell, IV and spectral response characteristics were measured under 1 sun to compare the bare glass properties. A graph showing the short-circuit current density versus voltage with or without cover glass is shown in FIG. As shown in Fig. 1, it was confirmed that the short circuit current density of the solar cell was reduced by 1.23 mA / cm < ² >. It can be confirmed that the current is lowered due to light loss due to total reflection at the upper part of the glass.

In addition, the external quantum efficiency (EQE) versus the wavelength depending on the presence or absence of the cover glass was measured, and a graph of the result is shown in FIG. As shown in Fig. 2, it was confirmed that the spectral response characteristic also decreased by 1.4 mA / cm < ^{2 &} gt ;.

Through these experiments, the control group was selected as a sample made of bare glass.

Random textured glass and Honeycomputed glass were used as experimental groups.

In order to confirm the difference in conversion efficiency, a solar cell module using a bare glass, a random textured glass, and a honeycombed glass as a cover glass was fabricated by using a quantum efficiency (QE) I then checked how the characteristics change.

The resulting graph is shown in FIG. As shown in FIG. 3, the random textured glass showed a lower short circuit current density than the bare glass, while the short circuit current density was increased in the honeycomb texture glass. That is, it was confirmed from FIG. 3 that the spectroscopic response characteristics of the wavelengths are generally improved as compared with the control group.

It is confirmed that the regular structure absorbs more light by inducing light scattering like a concave lens in addition to the light penetrating straight from the structure when the sunlight is incident.

Figs. 4 and 5 show images showing the surfaces of the random texture glass and the honeycomb textured glass, respectively. It can be confirmed that the honeycomb structure of FIG. 5 is clearly a honeycomb structure.

Further, in the production of the honeycomb textured glass, additional experiments were carried out while varying the etching method. FIG. 6 is a graph showing the spectral response characteristics of the honeycomb-textured glass with respect to the wavelengths of the concave-convex structures having various depths according to various etching methods.

Here, the unevenness of the cover glass manufactured through Etch-1 was in the form of a shallow bowl, and its height (depth) was approximately 500 to 600 nm. Etch-2 has a structure height of 1.9-2.1 μm and is named trapezoid. Through the Etch-3, a honeycomb glass texturing structure was formed and its height was 1.2 ~ 1.3 ㎛. It was confirmed that Etch-4 had a height of 600 ~ 700nm.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims. It can be understood that it is possible.

Claims (10)

As a cover glass for a solar cell module,
A pattern of concavo-convex structures regularly arranged on the first surface of the cover glass is formed,
Wherein the convex-and-concave structure exhibits the effect of the concave lens and diffuses the light transmitted through the first surface of the cover glass.
The method according to claim 1,
Wherein the pattern comprises a plurality of regularly arranged polygonal or circular concave-convex structures.
The method according to claim 1,
Wherein the pattern is a honeycomb structure.
The method according to claim 1,
Wherein the light transmitted through the first surface of the cover glass is reflected by the second surface of the cover glass and then travels toward the first surface and the path changes in the first surface. Glass.
The method according to claim 1,
Wherein the average depth of the concavities and convexities is 600 nm to 2.1 占 퐉.
Board;
A solar cell formed on the substrate;
An encapsulating material surrounding the substrate and the solar cell;
A backsheet formed on one surface of the encapsulant; And
And a cover glass formed on the other surface of the sealing material,
The cover glass has a concave-convex structure pattern regularly arranged on one surface thereof,
Wherein the convex-and-concave structure exhibits the effect of the concave lens, and optically diffuses the light transmitted through the first surface of the cover glass.
The method according to claim 6,
Wherein the pattern comprises a plurality of regularly arranged polygonal or circular concave-convex structures.
The method according to claim 6,
Wherein the pattern is a honeycomb structure.
The method according to claim 6,
Wherein the light transmitted through the first surface of the cover glass is reflected by the second surface of the cover glass and then travels toward the first surface and the path changes in the first surface. Glass.
The method according to claim 6,
And the average depth of the unevenness is 600 nm to 2.1 mu m.

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