JP2004140100A - Thin-film solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin-film solar cell module in which wiring is laid so that the effective area of a light receiving surface used for power generation may not be disturbed and which has highly reliable insulation properties or water resistances between the wiring and a photoelectric semiconductor layer and in the vicinities of electrodes by a simple means. <P>SOLUTION: The wiring is buried in a filler while an insulating tape is arranged on one surface of the wiring facing a back electrode and, at the same time, the wiring and insulating tape are arranged in the gap between the back electrode and bus bars at the contacts of the wiring with the bus bars. Consequently, the effect of the thermal expansion and contraction of the insulating tape in the vicinities of bus bar areas can be reduced. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a thin-film solar cell, and more particularly, to an insulating structure of a thin-film solar cell.
[0002]
[Prior art]
A thin-film solar cell has a plurality of power generation cells on a transparent insulating substrate such as glass. The power generation cells are electrically connected in series to output a high voltage.
[0003]
The solar cell module is provided with connection means such as a terminal box for supplying electric power to the outside. It is desirable that the wiring for guiding the electric power generated by the thin-film solar cell to a connection means such as a terminal box does not obstruct the effective area of the light receiving surface used for power generation as much as possible. As such a wiring method, a thin-film solar cell in which wiring is arranged along the back surface (the surface opposite to the light receiving surface) of a power generation cell is known. In this method, some insulating means is provided between the back surface of the power generation cell and the wiring.
[0004]
The following configuration is known as an insulating means between the back surface of the power generation cell and the wiring (see Patent Document 1). Referring to FIG. 3, the thin-film solar cell includes a plurality of power generation cells 101 connected in series, and the power generated by power generation cells 101 is collected on electrodes 102. The electric power collected by the electrode 102 is supplied to the outside of the solar cell module through the conductive material 103 and the wiring 104. In order to insulate between the wiring 104 and the power generation cell 101, an insulating material 105 is laid on the power generation cell 101 in a strip shape. The power generation cell 101 is protected by a filler 106 that is a thermoplastic resin. The filler 106 is sealed with a protective cover 107.
[0005]
As an insulating means between the back surface of the power generation cell and the wiring, as shown in FIG. 4, a configuration in which the wiring 104 is entirely covered with an insulating material 108 to insulate the wiring 104 from the power generation cell 101 is known. (See Patent Document 1).
[0006]
A solar cell is used in a state where it is installed outdoors for a long period of more than 20 years. Therefore, the insulation of the solar cell needs to be stably maintained for a long time. In connection with insulation properties, high waterproofness is required to maintain durability for long-term use.
[0007]
[Patent Document 1] Japanese Patent Application Laid-Open No. 9-326497
[Problems to be solved by the invention]
An object of the present invention is to provide a thin-film solar cell module that maintains high insulation or water resistance during long-term use, and a method for manufacturing the same.
[0009]
It is another object of the present invention to provide a thin-film solar cell module having a simple structure while maintaining high insulation or water resistance during long-term use, and a method for manufacturing the same.
[0010]
Another object of the present invention is to provide a thin-film solar cell module which maintains high insulation or water resistance during long-term use and has a simple manufacturing method, and a method for manufacturing the same.
[0011]
[Means for Solving the Problems]
Hereinafter, the means for solving the problem will be described using the numbers used in [Embodiments of the Invention] in parentheses. These numbers are added to clarify the correspondence between the description in the claims and the embodiment of the invention. However, those numbers should not be used to interpret the technical scope of the invention described in [Claims].
[0012]
The thin-film solar cell module (1) according to the present invention has a substrate (2). On the main surface of the substrate (2), a power generation cell (7) for generating electric power by the received light is provided. The power generated by the power generation cell (7) is collected on the conductor (8a). The conductor (8a) is connected to a foil-shaped wiring (10) for extracting the electric power generated by the power generation cell (7) to the outside of the thin-film solar cell module (1). Of the plurality of surfaces of the wiring (10), an insulating material (11) is disposed on a surface facing the power generation cell (7) to insulate the wiring (10) from the power generation cell (7).
[0013]
The thin-film solar cell module having such a configuration has a simple structure and is manufactured by a simple manufacturing method.
[0014]
Further, the thin-film solar cell module (1) of the present invention includes a protective cover (13) for covering the main surface side of the substrate (2). A filler (12) is filled between the power generation cell (7) and the protective cover (13). The filler (12) blocks the inside of the thin-film solar cell module (1) from the influence of the outside air, and prevents deterioration of the members.
[0015]
The wiring (10) and the insulating material (11) are embedded in the filler (12). The wiring (10) has a plurality of surfaces, of which the opposite surface facing the power generation cell (7) is bonded to the insulating material (11), and the other surface is directly in contact with the filler (12). ing.
[0016]
When both surfaces of the wiring (10) are covered with the insulating material (11), the insulating materials (11) on both surfaces do not adhere linearly along the side surface of the wiring due to the thickness of the foil used for the wiring (10). A gap (19) is created. This gap (19) is a space where no filler is present, and may be a path for water to enter. Of the plurality of surfaces of the wiring (10), the surface facing the power generation cell (7) is in close contact with the insulating material (11), and the other surface is in direct contact with the filler (12). Such a gap (19) cannot be formed, and the area around the wiring (10) and the insulating material (11) is filled with the filler (12) without any gap. Thereby, the wiring (10) and the covering material (11) are shielded from air and moisture, and high insulation or water resistance is maintained for a long time.
[0017]
Further, in the configuration in which only the opposing surface of the wiring (10) is covered with the insulating material (11), the number of assembly steps is smaller than that in which the other surface of the wiring (10) is also covered, and the members used can be saved. .
[0018]
In the thin-film solar cell module according to the present invention, the conductor (8a) for collecting electric power includes the electrode (8) and the conductive material (9). The electrode (8) is connected to the conductive material (9) by a plurality of contacts (20). A wiring (10) is connected to the conductive material (9), and the wiring (10) is insulated from the power generation cell (7) by an insulating material (11) disposed on one surface thereof.
[0019]
The part of the wiring (10) that is joined to the conductive material (9) and the part of the insulating material (11) that is joined to the wiring (10) at that joint are the electrode (8) and the conductive material. It is arranged between (9).
[0020]
In the thin film solar cell module (1) having such a configuration, when the insulating material (11) is elongated by heat, the insulating material (11) is laid between the electrode (8) and the conductive material (9). Therefore, there is no problem of deformation by hitting the conductive material (9). When the insulating material (11) contracts due to heat, the insulating material (11) is disposed above the electrode (8) at the time of installation, and thus is disposed over the electrode (8) of the insulating material (11). Even if the part shrinks, the insulation between the wiring (10) and the power generation cell (7) is reliably maintained. Therefore, the thin-film solar cell module having such a configuration has stable properties against thermal expansion and contraction of the insulating material, and maintains high insulating properties in long-term use.
[0021]
Further, when the insulating material (11) thermally expands and collides with the conductive material (9) and deforms, the insulating material (11) presses the filler (12), and the filler (12) is placed near the insulating material (11). There is a possibility that a gap without 12) may occur. These gaps can be a path for moisture to enter during long-term use. The thin-film solar cell module according to the present invention reduces the possibility of forming such gaps and maintains high water resistance during long-term use.
[0022]
Further, by adopting such a configuration, the condition required for design with respect to the thermal expansion and contraction property of the insulating material (11) is relaxed, so that the degree of freedom in selecting a material while maintaining high reliability is maintained. Increase.
[0023]
Further, the thin-film solar cell module having such a configuration has a simple structure and is manufactured by a simple manufacturing method.
[0024]
Further, in the thin-film solar cell module according to the present invention, the wiring (10) and the insulating material (11) are in close contact with each other without a continuous gap in the longitudinal direction. The adhesion is performed by means exemplified in vacuum lamination.
[0025]
The thin-film solar cell module having such a configuration reduces the possibility that the relative position between the wiring (10) and the insulating material (11) shifts, and maintains high insulating properties during long-term use. If the wiring (10) and the insulating material (11) are in close contact with each other in a state where there is no continuous gap in the longitudinal direction, there is no gap that may become a moisture intrusion path, and in a long-term use. The possibility that the wiring (10) and the insulating material (11) come off gradually is reduced. Therefore, high insulation or water resistance is maintained during long-term use.
[0026]
When manufacturing a thin-film solar cell module having such a configuration, an insulating material (11) is brought into close contact with one surface of the wiring (10), and then the wiring (10) is oriented such that one surface faces the power generation cell (7). Are joined to the conductor (8a). Such a method for manufacturing a thin-film solar cell has a special precaution to prevent the relative positions of the wiring (10) and the insulating material (11) from shifting when the wiring (10) is installed in the thin-film solar cell module (1). And high reliability can be obtained with simple work.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a thin-film solar cell module according to the present invention will be described with reference to the drawings.
[0028]
FIG. 1 is a sectional view showing an embodiment of a thin-film solar cell module according to the present invention. The thin-film solar cell module 1 includes an insulating substrate 2 made of a transparent material such as glass. A transparent electrode layer 4 is formed on the insulating substrate 2, a thin-film semiconductor layer 5 made of a photoelectric element is formed on the transparent electrode layer 4, and a back electrode layer 6 is formed on the thin-film semiconductor layer 5. You. The three layers of the transparent electrode layer 4, the thin film semiconductor layer 5, and the back electrode layer 6 constitute the power generation layer 3.
[0029]
The power generation layer 3 is divided into a plurality of power generation cells 7 connected in series and electrodes 8 at both ends of the power generation cell 3 by being processed by a laser. On the back electrode layer 6 of the electrode 8, a bus bar 9 which is a good conductor is provided.
[0030]
The bus bar 9 is connected to a copper foil wiring 10. The wiring 10 is arranged along the back electrode layer 6 of the power generation cell 7. A strip-shaped insulating material 11 is adhered to the surface of the wiring 10 facing the back electrode layer 6 to insulate the wiring 10 from the power generation cell 7. As a material of the insulating material 11, a PET (polyethylene terephthalate) resin is preferably used.
[0031]
The wiring 10 and the insulating material 11 are bonded in advance by bonding means exemplified by vacuum lamination. The insulating material 11 thus bonded securely insulates between the wiring 10 and the back surface electrode layer 6 by a simple means without displacing the relative arrangement with the wiring 10. The operation of bonding the insulating material 11 to one surface of the wiring 10 requires fewer steps and uses less members than the operation of coating both surfaces.
[0032]
The back electrode layer 6 is protected by the filler 12. The filler 12 is a thermoplastic resin. The filler 12 buries the wiring 10 and the insulating material 11 and protects the inside of the solar cell module 1 from the influence of the outside air. Examples of the filler 12 include resins such as EVA (ethylene / vinyl acetate copolymer), PVB (polyvinyl bratyl), and silicone.
[0033]
The surface of the wiring 10 facing the power generation cell 7 is covered with the insulating material 11, and the other surface is in direct contact with the filler. Referring to FIG. 5, when both sides of foil-shaped wiring 10 are covered with strip-shaped insulating material 11, linear gaps 19 are formed along both side surfaces of wiring 10 due to the thickness of wiring 10. The gap 19 is a space in which the filler 12 is not filled, and may be a path through which moisture enters. The gap 19 may gradually widen over a long period of use. In a configuration in which the surface of the insulating material 11 facing the power generation cell 3 is covered with the insulating material and the other surface is in contact with the filler, no gap 19 is generated.
[0034]
When a copper foil is used as the wiring 10 and EVA is used as the filler 12, the thickness of the wiring 10 is about 50 μm, and the EVA enters a gap of about 10 μm. Therefore, the filler 12 is filled without gaps around the wiring 10 and the insulating material 11 coated on one surface thereof, and high waterproofness can be obtained.
[0035]
The filler 12 is sealed with a protective cover 13. The wiring 10 is guided into the terminal box 15 through the outlet 14 provided in the protective cover 13, and is connected to the terminal 17. A cable (not shown) is connected to the terminal 17, and the cable (not shown) extends outside the terminal box 15. The inside of the terminal box 15 is filled with a potting material and protected.
[0036]
FIG. 2 shows a configuration of a connection portion between the bus bar 9 and the wiring 10 in the present invention. An insulating material 11 is disposed on the back electrode layer 6, and a wiring 10 having a smaller width is bonded on the insulating material 11. One end of the insulating material 11 and the wiring 10 is placed in the region of the electrode 8.
[0037]
A bus bar 9 is provided on the back electrode layer 6 of the electrode 8 so as to straddle the insulating material 11 and the wiring 10. Bus bar 9 is connected to back electrode layer 6 by solder 20. The bus bar 9 and the wiring 10 are connected by solder 21. The solder 20 or the solder 21 may be replaced by another conductive adhesive member exemplified by a conductive paste.
[0038]
In the thin-film solar cell module having such a configuration, when the insulating material 11 thermally expands, the insulating material 11 is disposed at a position that passes through the gap between the bus bar 9 and the back electrode layer 6. Stretch without hitting 9 without deformation. When the insulating material 11 is thermally contracted, even if the wiring 10 comes into contact with the electrode 8, a short circuit does not occur. To maintain. Therefore, the thin-film solar cell module according to the present invention has stable properties against thermal expansion and contraction of the insulating material.
[0039]
By adopting such an arrangement, the design requirements for the thermal expansion and contraction of the material used as the insulating material 11 are relaxed, so that the degree of freedom in selecting the material used as the insulating material 11 is maintained while maintaining high reliability. Get higher.
[0040]
【The invention's effect】
According to the present invention, there is provided a thin-film solar cell module that maintains high insulation or water resistance during long-term use, and a method for manufacturing the same.
[0041]
According to the present invention, there is provided a thin-film solar cell module having a simple structure while maintaining high insulating properties or water resistance during long-term use.
[0042]
ADVANTAGE OF THE INVENTION According to this invention, the solar cell module which maintains high insulation and water resistance in long-term use is provided with a simple manufacturing method.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing an embodiment of the present invention.
FIG. 2 is a perspective view showing the vicinity of a bus area according to the embodiment of the present invention.
FIG. 3 is a laminated perspective view showing an embodiment of an insulating structure according to a conventional invention.
FIG. 4 is a laminated perspective view showing an embodiment of an insulating structure according to a conventional invention.
FIG. 5 is a cutaway perspective view showing a foil-shaped wiring whose both surfaces are covered with an insulating material.
[Explanation of symbols]
REFERENCE SIGNS LIST 1 solar cell module 2 transparent insulating substrate 3 power generation layer 4 transparent electrode layer 5 thin film semiconductor layer 6 back electrode layer 7 power generation cell 8 electrode 8 a conductor 9 conductive material 10 wiring 11 insulating material Reference Signs List 12 filler 13 protective cover 14 outlet 15 terminal box 16 potting material 17 terminals 20, 21 solder 101 power generation cell 102 electrode 103 conductive material 104 wiring 105 insulating material 106 filler 107: protective cover 108: insulating material

Claims (6)

Board and
A power generation cell formed on the main surface of the substrate and generating electric power by received light,
A conductor for collecting the power;
A foil-shaped wiring connected to the conductor and for taking out the electric power outside the thin-film solar cell module;
Among a plurality of surfaces of the wiring, the insulating material is disposed on a facing surface facing the power generation cell, and includes an insulating material that insulates the wiring and the power generation cell.
Thin film solar cell module. The thin-film solar cell module according to claim 1, further comprising:
A protective cover that covers the main surface side of the substrate;
Comprising a filler filled between the power generation cell and the protective cover,
The wiring and the insulating material are embedded in the filler,
Among the plurality of surfaces of the wiring, a surface other than the facing surface is in direct contact with the filler. The thin-film solar cell module according to claim 1 or 2,
The conductor is
An electrode connected to the power generation cell,
A conductive material extending along the electrode and connected to the electrode at a plurality of contacts,
The wiring is joined to the conductive material,
A thin-film solar cell module in which a bonding portion of the wiring bonded to the conductive material and a portion of the insulating material bonded to the bonding portion are located between the electrode and the conductive material. A power generation cell that generates electric power by the received light,
An electrode for collecting the power;
A conductive material extending along the electrode and connected to the electrode by a plurality of contacts;
A foil-shaped wiring connected to the conductive material and for taking out the electric power outside the thin-film solar cell module;
Among the plurality of surfaces of the wiring, the insulating material is disposed on a facing surface facing the power generation cell, and includes an insulating material that insulates the wiring from the power generation cell,
A thin-film solar cell module in which a bonding portion of the wiring bonded to the conductive material and a portion of the insulating material bonded to the bonding portion are located between the electrode and the conductive material. The thin-film solar cell module according to any one of claims 1 to 4,
The insulating material and the wiring were adhered in a state where there was no continuous gap in the longitudinal direction,
Thin film solar cell module. Forming a power generation cell that generates electric power by the received light;
Providing a conductor for collecting the power;
Bonding an insulating material in a strip shape to one side of the foil-like wiring;
Bonding the wiring to the conductor with the one surface facing the power generation cell.

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