JPH07202230A - Solar battery module with natural deterioration recover function - Google Patents

Abstract

PURPOSE:To make the light deterioration of an amorphous silicon solar battery element recover naturally and suppress it to the minimum, by covering the solar battery element with thermal insulators excepting its light receiving sur face. CONSTITUTION:A translucent surface protecting material 3 and a rear-surface protecting material 4 are bonded respectively to an amorphous silicon solar battery 1 by a laminating agent 2. In this case, a blue plate glass is used as the translucent surface protecting material 3, and Tedlar(R) is used as the rear-surface protecting material 4. Thereafter, by a bonding agent 5, thermal insulators 6, 7 are bonded respectively to the protecting materials, etc. As the bonding agent 5, a silicon based corking agent is used, and as the thermal insulators 6, 7, urethane rubbers having a identical material quality to each other are used. Further, by a bonding agent 8 of a silicon based caulking agent, a frame 9 made of aluminum is mounted on the thermal insulator, and electrodes are led out therefrom. Thereby, when the solar battery module 1 is used for a long time in the open air, high-efficiency annealing is made possible, and accordingly, its light deterioration can be recovered more effectively.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to photodegradation of an amorphous silicon solar cell module, and in particular, it effectively recovers photodegradation by effectively using a heat insulating agent or a heat absorber. The present invention relates to an amorphous silicon solar cell module that minimizes

[0002]

2. Description of the Related Art Among solar cell modules for converting light energy from the sun into electric energy, an amorphous silicon solar cell module has a problem that the conversion efficiency is lowered by sunlight, so-called photodegradation occurs. It is known that this photodegradation is restored to a certain level by heat treatment (annealing) of the amorphous silicon solar cell element. However, the conventional amorphous silicon solar cell module is not designed to effectively recover the photodegradation by annealing at the same time when it is installed outdoors. Japanese Patent Application Laid-Open No. 4-71276 proposes a low-degradation solar cell module having a heat insulating means on the back side of a light-receiving surface of an amorphous silicon solar cell, which uses a glass fiber on a sheet as a heat insulating means. A slight annealing effect is recognized in the battery module. Further, in JP-A-60-60777, a heat absorbing layer, a heat collecting plate and a heat collecting tube are used by utilizing the property that an amorphous silicon film absorbs only light having a wavelength of 0.8 μm or less. Therefore, it is proposed that light having a wavelength shorter than 0.8 μm be used for power generation of a solar cell, and light having a wavelength longer than 0.8 μm be converted to thermal energy.

[0003]

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention
In the case of Japanese Patent Laid-Open No. 276, the heat insulating means is applied only to the back surface of the light receiving surface, which is insufficient as heat insulating means for radiating heat from the periphery of the solar cell element, and a sufficient annealing effect is not obtained. Further, according to Japanese Patent Laid-Open No. 4-71276,
The glass fiber on the sheet used as the heat insulating means has a hygroscopic property and is not suitable as a heat insulating agent for a solar cell module installed outdoors.

In JP-A-60-60777, 0,
The feature is that light with a wavelength of 8 μm or more is converted into heat energy by a heat absorption layer and collected through a heat collecting plate and a heat collecting tube. It has not been devised for use in recovery from deterioration.

Conventionally, when an amorphous silicon solar cell module is installed outdoors, a thermal annealing method for effectively and effectively recovering photodegradation by effectively utilizing the light energy from the sun. Has not been devised.

[0006]

Means for Solving the Problems As a result of intensive investigations by the present inventors, the inventors have sought to utilize light energy from the sun as effectively as possible for thermal annealing of an amorphous solar cell module by making full use of a heat insulating means. The present invention has been accomplished by contriving a solar cell module that is covered with a heat insulating material except for the light receiving surface of an amorphous silicon solar cell element.

That is, the present invention is a solar cell module characterized in that an amorphous silicon solar cell element is covered with a heat insulating material except for the light receiving surface of the element, and infrared rays are selectively emitted. A solar cell module, characterized in that a heat absorber that absorbs into and is converted into heat is attached to the upper surface side of the amorphous silicon solar cell element. In the present invention, what is used as a heat insulating material is one having a low hygroscopic property, for example, foamable plastic,
Alternatively, it is preferable to use a foamable inorganic substance, but the invention is not limited to this. In addition, the material of the heat insulating material may be different between the back surface of the light receiving surface of the solar cell element and the other surface. In such an amorphous silicon solar cell module, sunlight energy that has not been converted to electrical energy is converted to heat, and the temperature of the solar cell element is raised to a temperature at which annealing effectively occurs. Can be kept at high temperature.

Further, a solar cell module is proposed in which a transparent infrared absorbing sheet is formed on the upper surface of an amorphous silicon solar cell element to absorb infrared rays from the sun and convert them into heat. In such an amorphous solar cell module, the energy of light having a wavelength in the infrared region can be converted into thermal energy, and the temperature of the solar cell element can be raised to a temperature at which annealing effectively occurs.

[0009]

【Example】

(Example 1 and Comparative Examples 1 and 2) (1) FIG. 1 showing an example of a solar cell module which is covered with a heat insulating material except the light-receiving surface of an amorphous silicon solar cell element will be described. The amorphous silicon solar cell element 1, the transparent surface protection material 3, and the back surface protection material 4 were bonded with the laminating agent 2. Here, soda-lime glass was used as the transparent surface protection material, and Tedlar was used as the back surface protection material. Then, the heat insulating materials 6 and 7 were bonded by the adhesive 5.

Silicone caulking agent was used as the adhesive 5, and urethane rubber of the same material was used for the heat insulating materials 6 and 7. Then, the frame 9 made of aluminum was attached by the adhesive 8 which was a caulking agent of silicon rubber type, and the electrodes were taken out to fabricate the solar cell module 1 . (2) As Comparative Example 1, FIG. 4 showing an example of an amorphous silicon solar cell module not covered with a heat insulating material will be described.

The amorphous silicon solar cell element 1, the transparent front surface protective material 3 and the back surface protective material 4 were adhered with a laminate material 2. After that, the aluminum frame 6 is attached by the adhesive 5 which is a silicone rubber caulking agent,
The electrodes were taken out and the solar cell module 4 was produced. Here, the transparent surface protection material, the back surface protection material, and the adhesive 5
For, the same material as the solar cell module 1 was used. (3) As yet another Comparative Example 2, FIG. 5 showing an example of an amorphous silicon solar cell module in which only the back surface is covered with a heat insulating material will be described.

The amorphous silicon solar cell element 1, the transparent surface protection material 3 and the back surface protection material 4 were adhered with a laminate material 2. Then, the heat insulating material 6 was bonded by the adhesive 5. After that, the aluminum frame 8 was attached with the adhesive 7 which is a silicone rubber-based caulking agent, and the electrodes were taken out to fabricate the solar cell module 5 . Here, the same material as the solar cell module 1 was used for the transparent surface protective material, the back surface protective material, the heat insulating material, and the adhesives 5 and 7.

These solar cell modules 1, 4 and 5
A photo-deterioration experiment was carried out using. The photodegradation experiment was carried out as follows according to Japanese Patent Laid-Open No. 4-71276.

A pedestal installed outdoors by covering the light-receiving surface side of the solar cell with aluminum foil (so that the light-receiving surface of the solar cell faces to the true south and forms an angle of 37 degrees with the ground plane).
A solar pyranometer and a thermistor were installed in the plant so that the solar radiation and temperature could be measured.

Further, in order to measure the current-voltage curve of the module, a commercially available personal computer, display, printer and IV curve tracer were attached.

With such a system, the amount of solar radiation is 1 at noon on a clear day.
When it is stable at 00 mW / cm ² , peel off the aluminum foil covering the light-receiving surface of the module, and measure the current-voltage curve and solar radiation of the module 10 minutes after the temperature of the solar cell surface is considered to have stabilized. The effective conversion efficiency was calculated to be 6.0% for the solar cell module 1.
Module 4 is 5.8%, solar cell module 5 is 5.
It was 7%. After the measurement, connect a resistor corresponding to the optimum load of the current-voltage curve, and then leave it outdoors for about 4 months. At noon on a sunny day, the module's effective conversion efficiency under the same conditions as the above measurement. I was asked for, solar cells Moji
5.5% for module 1 and 4.9 for solar cell module 4
%, And the solar cell module 5 was 5.0%.

That is, the degree of photodegradation depends on the solar cell module.
Module 1 is 8.3%, solar cell module 4 is 15.5
%, And the solar cell module 5 was 12.3%. At this time, at the same time, a thermometer was set on the back surface of these solar cell modules, and when the value was measured when it was stable,
Temperature of the solar cell module 1 for a solar cell module 4 high 14 ° C., solar the solar cell module 5
The temperature of the battery module 1 was 7 ° C. higher.

Example 2 FIG. 2 showing an example of a solar cell module in which a heat absorber that selectively absorbs infrared rays and converts it into heat is attached to the upper surface side of an amorphous silicon solar cell element will be described. .

The amorphous silicon solar cell element 1, the infrared selective heat collecting agent sheet 3 and the back surface protective material 6 were adhered with a laminate material 2. Here, a heat absorbing resin film was used as the infrared selective heat collecting sheet, and a Tedlar was used as the back surface protective material. After that, the transparent adhesive 4 was used to adhere the transparent surface protective material 5. Here, soda lime glass was used as the transparent surface protective material. After that, an aluminum frame 8 is formed by an adhesive 7 which is a silicone rubber caulking agent.
Attach the solar cell module to remove the electrode
2 was produced.

The solar cell module thus produced
When the photodegradation test of Rule 2 was performed in the same manner as in Example 1, the effective conversion efficiency of 10 minutes after the module was installed was 5.
It was 9%, and the effective conversion efficiency after about 4 months was 5.1%. That is, the degree of photodegradation was 13.6%.
At this time, at the same time, a thermometer was set on the back surface of this solar cell module, and when the value was measured when it was stable,
The temperature of the solar cell module 2 was 5 ° C. higher than that of the solar cell module 4 .

(Example 3) In a solar cell module in which a heat absorber that selectively absorbs infrared rays and converts it into heat is attached to the upper surface side of an amorphous silicon solar cell element, heat insulation is performed except for the light receiving surface. FIG. 3 showing an example of the solar cell module characterized by being coated with the agent will be described.

The amorphous silicon solar cell element 1, the infrared selective heat collecting agent sheet 3, and the back surface protective material 6 were adhered with the laminating material 2. Here, a heat absorbing resin film was used as the infrared selective heat collecting sheet, and a Tedlar was used as the back surface protective material. After that, the transparent adhesive 4 was used to adhere the transparent surface protective material 5. Here, soda lime glass was used as the transparent surface protective material. After that, the heat insulating materials 8 and 9 were bonded by the adhesive 7 which is a silicone rubber caulking agent. Here, the heat insulating materials 8 and 9 are made of urethane rubber of the same material. Then, the frame 11 made of aluminum was attached by the adhesive 10 which is a silicone rubber-based caulking agent, and the electrodes were taken out to fabricate the solar cell module 3 .

Solar cell module produced in this way
When the photodegradation test of Rule 3 was performed in the same manner as in Example 1, the effective conversion efficiency of 10 minutes after the module was installed was 6.
It was 0%, and the effective conversion efficiency after about 4 months was 5.6%. That is, the degree of photodegradation was 6.7%. At this time, set the thermometer on the back of this solar cell module,
Was measuring the value at which stable, solar battery mode
The temperature of the solar cell module 3 is 18 for Joule 4 .
℃ high, solar cell module to the solar cell module 5
The temperature of Tool 1 was 11 ° C. higher.

The conversion efficiencies of the amorphous silicon solar cell modules 1 to 5 used in the above-mentioned Examples 1 to 3 were all about the degree of identification.

[0025]

In the amorphous silicon solar cell module, when the whole of the amorphous silicon solar cell element excluding the light receiving surface is covered with a heat insulating material rather than heat insulating means only on the back surface side of the light receiving surface. , Effectively reduce the heat dissipation of the solar cell element, keep the temperature of the solar cell element higher, and enable high-efficiency annealing when used outdoors for a long time, making the light deterioration more effective. Can be recovered.
Similarly, by attaching a heat absorber that selectively absorbs infrared rays and converts it into heat, it is possible to perform highly efficient annealing when used outdoors for a long time. Therefore, the photodegradation can be recovered more effectively.

[Brief description of drawings]

FIG. 1 is a sectional view of a solar cell module 1 of the present invention.

FIG. 2 is a sectional view of the solar cell module 2 of the present invention.

FIG. 3 is a sectional view of the solar cell module 3 of the present invention.

FIG. 4 is a cross-sectional view of a solar cell module 4 of a comparative example.

FIG. 5 is a cross-sectional view of a solar cell module 5 of a comparative example.

[Explanation of symbols]

 1 Solar cell element 2 Laminate material

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuhiro Fukuda 1190 Kasama-cho, Sakae-ku, Yokohama-shi, Kanagawa Mitsui Toatsu Chemical Co., Ltd.

Claims (2)

[Claims] 1. A solar cell module comprising an amorphous silicon solar cell element, which is covered with a heat insulating material except the light receiving surface of the element. 2. A solar cell module, wherein a heat absorber that selectively absorbs infrared rays and converts it into heat is attached to the upper surface side of the amorphous silicon solar cell element.