JP4224161B2 - Solar cell module - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a solar cell module.
[0002]
[Prior art]
Since solar cell modules are used in severe outdoor environments such as on the roof, there is a strong demand for improving the environmental performance of solar cells. Conventionally, in order to maintain the environmental resistance performance of solar cells, various researches have been conducted on constituent members of solar cell modules and combinations of the respective members.
[0003]
FIG. 4 shows an example of a conventional thin film solar cell module. This solar cell module is the same as that disclosed in Utility Model Registration Publication No. 2563877. In FIG. 4, a plurality of thin-film solar cells 2 are provided on the back surface of the front cover glass 1 as a transparent substrate, and these solar cells 2 are connected in series and / or in parallel by a back electrode 3. ing. The output electrode 4 made of, for example, a metal foil is connected to the back electrode 3. These back surfaces are sealed with the filler 5. Specifically, the filler 5 is formed, for example, by hot-melting EVA with the end of the output lead-out line 4 standing. The back surface side of the filler 5 is covered with a back surface sealing material (weather-resistant film) 6 having a three-layer structure in which both surfaces of the metal foil 6a are sandwiched between insulating films 6b. The back surface sealing material 6 is provided with a through hole as an output extraction portion O for extracting the output extraction line 4 to the outside. The output lead-out line 4 is routed to the back surface side of the back surface sealing material 6 through the through hole. A terminal 7 is attached to the end of the output lead-out line 4 routed to the outside by soldering or screwing, and an output lead 8 is connected to the terminal 7. A terminal portion including these output lead wire 4, terminal 7 and output lead wire 8 is covered with a terminal box 9.
[0004]
The exposed portion of the filler 5 and the output lead-out line 4 in the output lead-out portion O may be sealed with a protective resin such as a silicone resin. Similarly, the surface of the terminal 8 may be sealed with a protective resin such as a silicone resin.
[0005]
FIG. 5 shows a conventional crystalline solar cell module. In FIG. 5, a plurality of crystalline solar cells 11 are provided on the back side of the front cover glass 1, and these solar cells 11 are connected by connection lines 12. Further, an output lead wire 4 made of, for example, a metal foil is connected to the solar cell 11 at the end. Other configurations are the same as those in FIG.
[0006]
In these solar cell modules, since the filler 5 is exposed to the outside air at the output extraction portion O, it cannot be said that the moisture resistance and waterproofness are sufficient. Further, even if the output extraction portion O is protected with a silicone resin or the like, the moisture-proof and waterproof properties are not sufficiently different from those exposed to the outside air. As a result, particularly when water enters the terminal box 9, moisture enters the filler 5 through the output extraction portion O. Therefore, corrosion of the output extraction line 4 and further corrosion of the back electrode 3 are likely to occur. This is a major weakness in terms of environmental resistance performance of solar cell modules. Actually, most of the troubles of the solar cell module are caused by problems such as corrosion of the back electrode 3 due to moisture entering from the outside.
[0007]
[Problems to be solved by the invention]
An object of the present invention is to provide a solar cell module excellent in environmental resistance performance.
[0008]
[Means for Solving the Problems]
The solar cell module of the present invention includes a transparent substrate, a solar cell provided on the back side of the transparent substrate, an output lead connected to the solar cell, and a filler for sealing the solar cell. And a first layer back surface sealing material provided on the back surface of the filler, and the output lead-out line passes from the inside of the filler to the back surface side of the back sealing material of the first layer through the output extraction part. In the routed solar cell module, the output lead-out line is formed by extending along the back surface of the solar cell module on a part of the back surface sealing material of the first layer through a further filler. And a second layer back surface sealing material formed on the other part of the back surface sealing material of the first layer and the extension portion of the output lead-out line via a further filler. further comprising a rear surface sealing material of the first layer in the extension of the output extraction line The laminated structure back surface sealing material are laminated with intervening filler between each other of the extensions and the second layer output extraction lines are formed directly filler of the output extraction portion and the outside air The back surface sealing materials of the first layer and the second layer have a three-layer structure in which both surfaces of the metal foil are sandwiched between insulating films. Here, the output extraction portion refers to a portion where the output extraction line crosses the back surface sealing material. As described above, the back surface sealing material having the three-layer structure in which both surfaces of the metal foil are sandwiched between the insulating films is particularly excellent in moisture resistance and water resistance.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Each member which comprises the solar cell module of this invention is demonstrated easily.
[0011]
A glass substrate or the like is used as the transparent substrate. A plurality of solar cells are provided on the back side of the transparent substrate. The photovoltaic element constituting the solar battery cell may be either a thin film system or a crystal system. Thin film solar cells are connected in series and / or in parallel by a back electrode. The back electrode is made of metal foil or conductive paste. Crystalline solar cells are connected by connection lines. An output lead-out line is connected to the thin-film solar cell through the back electrode, and an output lead-out line is directly connected to the terminal cell of the crystalline solar cell. As will be described later, these output lead wires are routed to the outside, and terminals and output lead wires are connected to the ends thereof.
[0012]
The above-described members such as the solar battery cell, the back electrode, the connection line, and the output lead-out line are sealed with a filler. As the filler, EVA (ethylene / vinyl acetate copolymer), PVB (polyvinyl butyral), silicone resin, or the like is used. The filler can be easily formed by a method such as hot melting.
[0013]
A back surface sealing material is provided on the back surface of the filler. For this backside sealing material, an insulating film excellent in moisture resistance and water resistance, such as a fluorine-based film or a PET film, is used alone, or two insulating films sandwiched on both sides of a metal foil made of aluminum or the like. Used in the form of a layered structure. Since the metal foil provided at the center of the back surface sealing material has a function of improving moisture resistance and water resistance, it is effective for protecting the solar battery cell from moisture.
[0014]
The output lead-out line is routed from the inside of the filler to the back side of the back side sealing material through the output take-out part. The output extraction portion is formed as a gap between the back surface sealing materials or a through hole provided in the back surface sealing material. A terminal is provided at the end of the output lead-out line routed to the outside, and an output lead wire is connected to this terminal. These terminal portions are accommodated in a terminal box.
[0015]
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0016]
FIG. 1 is a cross-sectional view showing an example of a thin film solar cell module according to the present invention. In FIG. 1, a plurality of thin-film solar cells 2 are provided on the back surface of a front cover glass 1 as a transparent substrate, and these solar cells 2 are connected in series and / or in parallel by a back electrode 3. ing. The output electrode 4 made of, for example, a metal foil is connected to the back electrode 3. These back surfaces are sealed with a filler 5 in a state where the output lead-out line 4 is routed. The back surface side of the filler 5 is covered with a back surface sealing material 6 having a three-layer structure in which both surfaces of the metal foil 6a are sandwiched between insulating films 6b. In this case, the gap between the two back surface sealing materials 6 serves as an output extraction portion O for extracting the output extraction line 4 to the outside. The output extraction line 4 taken out from the output extraction portion O is extended along the back surface of the solar cell module. That is, the back surface sealing material 6 on one side is overlaid on the filler 5, the output extraction line 4 routed to the outside from the EVA and the output extraction portion O is superimposed on the back surface sealing material 6, and the output extraction line 4 is further extended. A laminated structure on the back surface side is formed by stacking EVA on the part and stacking the back surface sealing material 6 on the other side and hot-melting. The length of the overlap portion (corresponding to the distance from the outside air to the output extraction portion) between the output extraction line 4 and the outer back surface sealing material 6 is desirably 10 mm or more, and the longer the length, the higher the effect. A terminal 7 is attached to the end of the output lead-out line 4 routed to the outside by soldering or screwing, and an output lead 8 is connected to the terminal 7. A terminal portion including these output lead wire 4, terminal 7 and output lead wire 8 is covered with a terminal box 9.
[0017]
As described above, in the solar cell module of the present invention, the filler 5 of the output extraction portion O is covered with the back surface sealing material 6 and is not in direct contact with the outside air. For this reason, the distance from the outside air to the filler 5 of the output extraction part O is longer than before, and it is possible to effectively prevent moisture from entering from the outside air. Therefore, corrosion of the output lead wire 4 and further corrosion of the back electrode 3 and the like can be suppressed, and the environmental resistance performance of the solar cell module can be improved. Moreover, since the above effect is acquired, it is not necessary to seal the inside of the terminal box 9 with a protective resin, and workability | operativity improves.
[0018]
FIG. 2 shows a cross-sectional view of a crystalline solar cell module according to the present invention. In FIG. 2, a plurality of crystalline solar cells 11 are provided on the back surface side of the front cover glass 1, and these solar cells 11 are connected by connection lines 12. Further, an output lead wire 4 made of, for example, a metal foil is connected to the solar cell 11 at the end. Other configurations are the same as those in FIG.
[0019]
FIG. 3 shows a cross-sectional view of another thin film solar cell module according to the present invention. In FIG. 3, the configuration of the solar battery cell 2, the back electrode 3, and the filler 5 on the back surface of the front cover glass 1 is the same as that in FIG. In this solar cell module, a through hole is provided in the back surface sealing material 6 to form an output extraction portion O, and the output extraction line 4 is routed to the back surface side of the back surface sealing material 6 on one side, and the filling material 5 is extended through. Further, another layer of the back surface sealing material 13 is laminated on the other side of the back surface sealing material 6 and the extended portion of the output lead-out line 4 via the filler 5.
[0020]
The solar cell module shown in FIG. 2 and FIG. 3 can obtain the same effect as that of FIG. 1, and can suppress the corrosion of the back electrode 3 and the connecting wire 12 and improve the environmental resistance performance.
[0021]
【The invention's effect】
As described above in detail, the solar cell module of the present invention can suppress corrosion of the back electrode and the connecting wire, and exhibits excellent environmental resistance.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view of a thin film solar cell module according to the present invention.
FIG. 2 is a cross-sectional view of a crystalline solar cell module according to the present invention.
FIG. 3 is a cross-sectional view of another thin film solar cell module according to the present invention.
FIG. 4 is a cross-sectional view of a conventional thin film solar cell module.
FIG. 5 is a cross-sectional view of a conventional crystalline solar cell module.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Surface cover glass 2 ... Thin film type photovoltaic cell 3 ... Back electrode 4 ... Output extraction line 5 ... Filler 6, 13 ... Back surface sealing material 6a ... Metal foil 6b ... Insulating film 7 ... Terminal 8 ... Output lead Line 9 ... Terminal box 11 ... Crystalline solar cell 12 ... Connection line

Claims (1)

A transparent substrate, a solar cell provided on the back side of the transparent substrate, an output lead line connected to the solar cell, a filler for sealing the solar cell, and a back surface of the filler A solar cell module comprising: a first-layer rear surface sealing material provided; and wherein the output lead-out line is routed from the inside of the filler to the rear surface side of the first-layer rear surface sealing material through an output extraction portion. The output lead-out line has an extension formed by extending along a back surface of the solar cell module on a part of the back surface sealing material of the first layer through a further filler, and further filling material And further including a second layer back surface sealing material formed on the other part of the back surface sealing material of the first layer and an extension portion of the output lead line through the output extraction line. backside sealing material of the first layer in the extension of the line, the extension of the output extraction line and Serial backside sealing material of the second layer laminated structure are laminated with intervening filler therebetween are formed, filler of the output extraction portion is in a state not in contact directly with the outside air, And the back surface sealing material of the said 1st layer and a 2nd layer has a three-layer structure which pinched both surfaces of metal foil with the insulating film, The solar cell module characterized by the above-mentioned.

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