JP2004327630A - Solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar cell battery module which prevents a power generation efficiency from being lowered by improving thermal conductivity in the solar cell module and suppressing the temperature rise during the power generation and which has proper heat sink properties even when a hot spot occurs. <P>SOLUTION: The solar cell module includes a transparent substrate, a photodetecting surface side charging material, a solar cell element, a rear surface side charging material, and a rear surface sheet sequentially arranged to be superposed with each other. In the solar cell module, the rear surface side charging material contains particles for increasing the thermal conductivity. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a solar cell module, and more particularly to a solar cell module with improved heat dissipation.
[0002]
[Prior art]
Solar cell elements are often manufactured using a single crystal silicon substrate or a polycrystalline silicon substrate. For this reason, the solar cell element is vulnerable to physical impact, and it is necessary to protect the solar cell from rain and the like when it is mounted outdoors. In addition, since a single solar cell element generates a small electric output, it is necessary to connect a plurality of solar cell elements in series and parallel so that a practical electric output can be obtained. For this reason, it is common practice to connect a plurality of solar cell elements and enclose the translucent substrate and a filler mainly composed of ethylene vinyl acetate copolymer (EVA) or the like to produce a solar cell module. .
[0003]
In a solar cell module installed outdoors, the temperature of the solar cell module rises to about 40 to 50 ° C. due to heat generated by the operation of the solar cell element even when the external temperature is 20 ° C. during power generation. As described above, when the temperature of the solar cell module increases, the power generation efficiency decreases due to the temperature characteristics of the solar cell element.
[0004]
Further, if one of the plurality of solar cell elements of the solar cell module that is generating power is shaded by some shadow and power generation becomes insufficient, the solar cell element becomes a resistor. At this time, a potential difference is generated between both electrodes of the solar cell element, which is the product of the resistance value and the flowing current. That is, a reverse bias voltage is applied to the solar cell element, and this element generates heat. Such a situation is called a hot spot. If the temperature of the solar cell element continues to rise due to the phenomenon of the hot spot, in the worst case, the solar cell element is broken, and thereafter, a predetermined electric output cannot be obtained from the solar cell module.
[0005]
In order to cool the solar cell module when a temperature rise or a hot spot occurs in the solar cell module as described above, the surface of the solar cell module is provided with a film having a high thermal emissivity on the back side of the solar cell module. It has been devised to provide a ventilation hole in a module frame provided around a battery module (see Patent Document 1).
[0006]
Prior art document information related to the invention of this application includes the following.
[0007]
[Patent Document 1]
JP-A-6-181333
[Problems to be solved by the invention]
However, as described above, in the method of providing a film having an uneven surface and a high thermal emissivity on the back side of the solar cell module, heat is accumulated inside the solar cell module due to poor heat conduction of a filler such as EVA. However, the temperature tends to rise and the heat radiation effect is insufficient.
[0009]
In addition, in the case where ventilation holes are provided in the module frame arranged around the solar cell module, the strength of the solar cell module may be affected, and the effect may be insufficient in the absence of wind. Can be
[0010]
Therefore, the present invention has been completed in view of the above circumstances, and an object of the present invention is to improve the thermal conductivity inside a solar cell module and suppress the temperature rise of the solar cell module during photovoltaic power generation, thereby reducing the power generation efficiency. It is another object of the present invention to prevent the solar cell element from being degraded by suppressing the temperature rise of the solar cell element when a hot spot is generated, while preventing a decrease in the temperature.
[0011]
[Means for Solving the Problems]
The solar cell module of the present invention is a solar cell module in which a light-transmitting substrate, a light-receiving surface-side filler, a solar cell element, a back-side filler, and a back sheet are sequentially disposed so as to overlap each other. It is characterized in that the side filler contains particles for increasing the thermal conductivity.
[0012]
Another solar cell module according to the present invention is characterized in that the particles for increasing the thermal conductivity are alumina or zirconia.
[0013]
[Action]
According to the solar cell module of the present invention, as in the above-described configuration, the solar cell includes a translucent substrate, a light-receiving surface-side filler, a solar cell element, a back-side filler, and a back sheet that are sequentially arranged so as to overlap each other. In the battery module, by including particles for increasing the thermal conductivity in the back side filler, without providing a heat dissipating material or the like for releasing heat between the solar cell element and the back side filler. However, in a solar cell module having an extremely simple structure, the heat generated from the solar cell element is quickly radiated to the outside through the back sheet by the back side filler having enhanced thermal conductivity, and the solar cell module at the time of photovoltaic power generation In addition to preventing a decrease in power generation efficiency by suppressing a rise in temperature, a rise in the temperature of the solar cell element is suppressed when a hot spot occurs, thereby preventing destruction of the solar cell element.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the solar cell module according to the present invention will be described in detail with reference to the drawings.
[0015]
FIG. 1 is a diagram showing a structure of a solar cell module according to the present invention.
[0016]
In the solar cell module 10 shown in FIG. 1, 1 is a translucent substrate, 2 is a light receiving surface side filler, 3 is a solar cell element, 4 is a back surface filler, 5 is a back sheet, and 6 is a connection wiring. .
[0017]
As the translucent substrate 1, a tempered glass having a thickness of about 3 to 5 mm is often used. As the filler 2 on the light-receiving surface side, a material mainly containing polyvinyl butyral (PVB) in addition to a transparent ethylene vinyl acetate copolymer (EVA) is often used. The solar cell element 3 is made of a single-crystal silicon or polycrystalline silicon substrate having a thickness of about 0.3 mm, and its approximate size is, for example, about 150 mm square in a polycrystalline silicon solar cell. When a solar cell module is manufactured, a connection wiring member 6 such as a copper foil having a width of about 1 to 7 mm applied with solder plating or the like is connected to electrodes of the solar cell element 3 by soldering or the like. The solar cell elements 3 are connected in series and parallel by soldering or the like with the connection wiring members 6 so that an electric output is generated.
[0018]
The back surface side filler 4 contains ethylene vinyl acetate copolymer (EVA), polyvinyl butyral (PVB), or the like as a main component. In this case, for example, since the thermal conductivity of EVA is as low as 0.2 W / mK, a metal having good thermal conductivity (for example, aluminum having a thermal conductivity of 203 W / mK) or the like is used to improve the thermal conductivity. Include ceramic particles. Further, since the backside filler 4 is desirably insulative in consideration of the insulation properties and withstand voltage performance of the solar cell module, alumina for filling the backside filler 4 with heat conduction is alumina. (Thermal conductivity 21 W / mK), zirconia (thermal conductivity 2.5 W / mK), and the like can be suitably used.
[0019]
The method of manufacturing the backside filler 4 is such that, for example, before the EVA is formed into a sheet, alumina or zirconia particles having a diameter of about 0.01 to 0.1 mm are added in a weight ratio of EVA1 to EVA1 of 0.1 to 0.1 mm. It becomes possible by kneading to about 5 to 2.
[0020]
By including alumina or zirconia particles in the backside filler 4 as described above, it is possible to improve the thermal conductivity of the solar cell element without losing the adhesiveness or filling property of EVA or the like. The heat and the like generated during the operation can be quickly transmitted to the back side of the solar cell module without accumulating in the back side filler 4, thereby suppressing a rise in the temperature of the solar cell element 3 and generating efficiency of the solar cell module. Can be prevented from decreasing.
[0021]
Further, even when the above-mentioned hot spot phenomenon occurs, it is possible to suppress the local temperature rise of the solar cell element 3 and prevent the solar cell element 3 from being broken.
[0022]
The back material 6 is made of, for example, a weather-resistant fluororesin sandwiching an aluminum foil to prevent the passage of humidity.
[0023]
The production of the solar cell module according to the present invention is performed as follows.
[0024]
A translucent substrate 1, a light-receiving surface-side filler 2, a solar cell element 3, a backside-side filler 4, and a backsheet 5 are sequentially stacked and superimposed as shown in FIG. 1, and under reduced pressure using a device called a laminator. The light-receiving-side filler 2 and the back-side filler 4 are cross-linked to form a solar cell panel while being pressed while heating to expel air bubbles and crosslink.
[0025]
Next, module frames (not shown) are attached to four sides of the integrated solar cell panel. This module frame is usually formed by extruding aluminum in consideration of the strength and cost required for the solar cell module, and its surface is often subjected to anodizing and clear coating.
[0026]
Further, a terminal box (not shown) for connecting the solar cell element to an external circuit is attached to the back surface side of the solar cell panel with an adhesive to complete the solar cell module.
[0027]
The present invention is not limited to the above embodiment, and many modifications and changes can be made within the scope of the present invention. For example, the solar cell element is not limited to a crystalline solar cell such as a single crystal or polycrystalline silicon, but can be applied to a thin film solar cell and the like.
[0028]
【The invention's effect】
As described above, according to the solar cell module of the present invention, a solar cell is provided by sequentially arranging a translucent substrate, a light-receiving surface-side filler, a solar cell element, a back-side filler, and a back sheet. In the module, by including particles for increasing the thermal conductivity in the backside filler, without providing a heat dissipating material or the like for releasing heat between the solar cell element and the backside filler. However, in a solar cell module having an extremely simple structure, the heat generated in the solar cell element can be quickly transmitted to the back side of the solar cell module and radiated from the back side, and the electric output of the solar cell module due to a temperature rise can be increased. Can be prevented from decreasing. In addition, even when local heat is generated at a hot spot or the like, the diffusion of heat is accelerated, so that destruction of the solar cell element can be prevented. Further, the light-receiving surface side of the solar cell module tends to increase in temperature as compared with the rear surface side due to light absorption or the like, but in the present invention, heat is radiated from the rear surface side without affecting the light-receiving surface side at all, and efficiently. The temperature rise of the solar cell module can be suppressed uniformly.
[Brief description of the drawings]
FIG. 1 is a diagram showing a structure of a solar cell module according to the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Translucent board 2 ... Light receiving surface side filler 3 ... Solar cell element 4 ... Back side filler 5 ... Back sheet 6 ... Connection wiring material

Claims (2)

A solar cell module in which a translucent substrate, a light-receiving surface-side filler, a solar cell element, a backside-side filler, and a backsheet are sequentially disposed so as to overlap each other. A solar cell module comprising particles for enlarging. The solar cell module according to claim 1, wherein the particles for increasing the thermal conductivity are alumina or zirconia.

Images