JP2013069898A - Solar cell module and method of manufacturing the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module preventing fracture of a substrate due to a thickness of a drawing electrode, and having excellent reliability.SOLUTION: The method of the solar cell module includes at least processes in order: a process A for providing a sheet-like sealing member 30 having a plurality of notches 31 across at least a part or entire of a photoelectric conversion body 12 after providing the photoelectric conversion body 12, a collector electrode 20, and a drawing electrode 21 laminated on one surface of a substrate 11; and a process B for providing a coating substrate 40 on the sealing member 30.

Description

  The present invention relates to a solar cell module capable of preventing a substrate from being cracked due to the thickness of an extraction electrode and a method for manufacturing the same.

  In recent years, solar cells are becoming more and more widely used from the viewpoint of efficient use of energy. For example, a solar cell using an amorphous (non-crystalline) silicon thin film is widely used as a low-cost solar cell.

Amorphous silicon solar cells use a semiconductor film having a layer structure called a pin junction in which an i-type amorphous silicon film that generates electrons and holes when receiving light is sandwiched between p-type and n-type silicon films. The electrodes are formed on both sides of the semiconductor film.
Electrons and holes generated by sunlight move in a predetermined direction due to the potential difference between the p-type and n-type semiconductors, and electricity is generated by repeating this continuously.

  As a specific configuration of such an amorphous silicon solar cell, for example, a transparent electrode such as TCO (transparent conductive oxide) is formed as a positive electrode (also referred to as a surface electrode) on a glass substrate on the light receiving surface side, A semiconductor film made of amorphous silicon, an Ag thin film to be a negative electrode (also called a back electrode), and the like are formed thereon. Since an amorphous silicon solar cell including a photoelectric conversion body composed of such upper and lower electrodes and a semiconductor film has a problem of resistance value only by forming each layer uniformly on a large area on a substrate, for example, FIG. As shown in FIG. 5, partitioning elements 112a are formed by electrically dividing the photoelectric conversion body 112 by a predetermined size, and the partitioning elements 112a adjacent to each other are electrically connected. Specifically, a plurality of strip-shaped partition elements 112a are formed by forming grooves called scribe lines (scribe lines) 119 with a laser beam or the like in the photoelectric converter 112 formed uniformly over a large area on the substrate 111. The partition elements are electrically connected in series.

Incidentally, as shown in FIG. 14, a solar cell is usually provided with a collecting electrode 120 for efficiently collecting electrons and holes, and a taking-out electrode 121 for taking out electricity, regardless of the type. (For example, refer to Patent Document 1).
Further, the solar cell includes a sealing member 130 disposed so as to cover at least the photoelectric converter 112 and a covering substrate 140 disposed on the sealing member 130. The extraction electrode 121 is led out through the seal member 130 and the covering substrate 140.
Such an extraction electrode 121 is made of, for example, a ribbon-shaped copper foil, or a ribbon-shaped copper foil and a plating layer provided around the ribbon-shaped copper foil.

  However, as shown in FIG. 15, such a thickness of the extraction electrode 121 causes unevenness in the substrate surface. In the conventional solar cell module, it is difficult for the sealing member 130 to absorb the thickness of the extraction electrode 121, and stress due to the thickness of the extraction electrode 121 is generated inside the solar cell module, and the substrate may be broken by this stress. It was a problem that deteriorated quality and reliability.

JP 2011-66292 A

  The present invention has been devised in view of such a conventional situation, and can prevent a substrate from cracking due to the thickness of an extraction electrode and can easily manufacture a highly reliable solar cell module. An object is to provide a method for manufacturing a module.

In the method for manufacturing a solar cell module according to claim 1 of the present invention, a photoelectric conversion body in which at least a first electrode layer, a semiconductor layer, and a second electrode layer are stacked in this order is formed on one surface of a substrate. A solar cell, a collector electrode disposed on the second electrode layer constituting the solar cell, and the second electrode layer comprising one end electrically connected to the collector electrode and constituting the solar cell; A solar cell module comprising: a take-out electrode disposed on the substrate; a sealing member disposed on at least one surface of the substrate so as to cover the photoelectric conversion body; and a coated substrate disposed on the sealing member. In the manufacturing method, after the photoelectric conversion body, the current collecting electrode, and the extraction electrode are provided on one surface of the substrate so as to overlap, a plurality of cuts are formed on the photoelectric conversion body over at least a part or the entire surface. Sheet with notches A step A of providing the sealing member, on the sealing member, to have a step B of providing the coated substrate, at least in this order, characterized by.
The method for manufacturing a solar cell module according to claim 2 of the present invention is the method according to claim 1, wherein, in the step A, the seal member has a portion corresponding to at least a part of the extraction electrode and the vicinity thereof. It uses the thing provided with two or more notch parts, It is characterized by the above-mentioned.
The method for manufacturing a solar cell module according to claim 3 of the present invention is the method according to claim 1 or 2, wherein after the step B, the sealing member is melted, and the photoelectric conversion body is sealed by the sealing member. In addition, the method further includes a step C of filling the notch.
The method for manufacturing a solar cell module according to claim 4 of the present invention is characterized in that, in any one of claims 1 to 3, the thickness of the sealing member is 50 μm to 1600 μm.

  In the method for manufacturing a solar cell module of the present invention, after the photoelectric conversion body, the current collecting electrode, and the extraction electrode are provided on one surface of the substrate so as to overlap, at least a part or the entire surface is formed on the photoelectric conversion body. Then, it includes at least a step A for providing the sheet-like sealing member having a plurality of notches and a step B for providing the covering substrate on the sealing member. Accordingly, in the present invention, stress on the substrate due to the thickness of the extraction electrode is less likely to be generated inside the solar cell module, and thus the generated stress is alleviated. Therefore, according to this invention, the manufacturing method of the solar cell module which can prevent a crack of a board | substrate and can manufacture a high quality solar cell module easily can be provided.

The disassembled perspective view which shows typically the 1st structural example of the solar cell module which concerns on this invention. Sectional drawing in the X1-X2 line in FIG. The perspective view explaining the manufacturing method of the solar cell module shown in FIG.1 and FIG.2. Sectional drawing in the X3-X4 line in FIG. The perspective view explaining the next process of FIG. Sectional drawing in the X5-X6 line in FIG. The perspective view explaining the next process of FIG. Sectional drawing in the X7-X8 line | wire in FIG. The perspective view explaining the next process of FIG. Sectional drawing in X9-X10 in FIG. The perspective view explaining the next process of FIG. Sectional drawing in the X11-X12 line | wire in FIG. The perspective view which shows the other structural example of a sealing member. The disassembled perspective view which shows one structural example of the conventional solar cell module typically. It is principal part expanded sectional drawing of the solar cell module shown in FIG. 17, and sectional drawing in the Y1-Y2 line | wire in FIG.

  Hereinafter, the solar cell module and the manufacturing method thereof according to the present invention will be described in detail with reference to the drawings. In addition, in order to make the features of the present invention easier to understand, the drawings used in the following description may show the main parts in an enlarged manner for convenience, and the dimensional ratios of the respective components are actually It is not always the same.

<First embodiment>
1 and 2 are diagrams schematically showing a configuration example of a solar cell module 1 manufactured according to the present invention, FIG. 1 is an exploded perspective view, and FIG. 2 is a cross section taken along line X1-X2 in FIG. FIG.
This solar cell module 1 includes a solar cell 10 in which a photoelectric conversion body 12 in which at least a first electrode layer 13, a semiconductor layer 14, and a second electrode layer 15 are stacked in this order on one surface 11a of a substrate 11 is formed. The collector electrode 20 disposed on the second electrode layer 15 constituting the solar cell 10, and the second electrode having one end electrically connected to the collector electrode 20 and constituting the solar cell 10 A take-out electrode 21 disposed on the layer 15, a sealing member 30 disposed on at least one surface 11 a of the substrate 11 so as to cover the photoelectric converter 12, and a coated substrate disposed on the sealing member 30 40.

  The solar cell 10 may be a known one, and examples thereof include an amorphous type and a microcrystal type, and further examples include a thin film type including a CIGS type and a CdTe type, a tandem type, and the like, but are not limited thereto.

  As shown in FIG. 2, the solar cell 10 shown here has at least a first electrode (lower electrode) layer 13, a semiconductor layer 14, and a second electrode layer (upper electrode) layer 15 in this order on one surface 11 a of a substrate 11. A photoelectric conversion body 12 is provided.

The board | substrate 11 should just be formed with the insulating material which is excellent in the transparency of sunlight, and has durability, such as the board | plate by glass, transparent resin, and the flexible film board | substrate which consists of those materials, for example. By making sunlight enter from the other surface 11b side of such a substrate 11, the solar cell 10 can be generated. If the present technology is applied to a plate-like substrate, the substrate can be prevented from cracking or cracking. When applied to a flexible film substrate, bubbles generated on the substrate surface or expansion / contraction of the flexible material can be prevented. The resulting irregularities can be relaxed.
In the case where light is incident from one surface 11a of the substrate 11, the covering substrate 40 is composed of a plate made of glass or transparent resin having excellent sunlight permeability, or a flexible film substrate made of such a material, and sealed. If the member 30 is also made of a material having excellent permeability, the substrate 11 may be made of a metal material.

The first electrode layer 13 only needs to be formed of a transparent conductive material, for example, a light-transmitting metal oxide such as TCO or ITO.
Moreover, the 2nd electrode layer 15 should just be formed with electroconductive metal bellows, such as silver (Ag) and copper (Cu).

  For example, when the solar cell 10 is a thin-film silicon solar cell, the semiconductor layer 14 has an i-type silicon film 16 sandwiched between a p-type silicon film 17 and an n-type silicon film 18 as shown in the upper part of FIG. A pin junction structure is formed. When sunlight enters the semiconductor layer 14, electrons and holes are generated, and the semiconductor layer 14 moves actively due to the potential difference between the p-type silicon film 17 and the n-type silicon film 18. A potential difference occurs between the electrode layer 13 and the second electrode layer 15 (photoelectric conversion). The silicon film may be either an amorphous type or a microcrystal (microcrystal) type.

  As shown in FIG. 1, the photoelectric converter 12 is usually divided by a scribe gland 19 into a large number of partition elements 12 a having, for example, a strip shape. For example, the partition elements 12a are electrically connected in series between the partition elements adjacent to each other. Thereby, the photoelectric conversion body 12 becomes the form which connected all the many division elements in series electrically, and can take out the electric current of a high electric potential difference. The scribe line 19 may be formed, for example, by forming a photoelectric converter 12 or a back electrode on one surface 11a of the substrate 11 and then forming grooves in the photoelectric converter 12 at a predetermined interval with a laser or the like.

  Although the semiconductor layer 14 has a single pin junction structure here, the present invention is not limited to this and the semiconductor layer 14 may be a tandem type in which the pin junction structure is a multi-layer such as two layers or three layers. In the case of the tandem semiconductor layer 14, the layer that performs photoelectric conversion can be adjusted according to the wavelength of light to be irradiated.

In the solar cell module 1 shown here, two ribbon-shaped collector electrodes 20 are provided on the photoelectric converter 12 of the solar cell 10.
As shown in FIG. 1, the surface of the photoelectric conversion body 12 has a substantially square shape, and the current collecting electrode 20 is disposed along two peripheral edges that are inward of the surface. Then, one end portion of the extraction electrode 21 is disposed on the collecting electrode 20, and the extraction electrode 21 and the collecting electrode 20 are electrically connected. The other end side of the extraction electrode 21 is bent so as to rise from the surface of the photoelectric converter 12 so that electricity can be easily extracted.
In the solar cell module 1, the protective sheet 22 and the insulating sheets 24 and 25 are disposed between the extraction electrode 21 and the photoelectric conversion body 12, so that the extraction electrode 21 and the photoelectric conversion body 12 do not come into contact with each other. ing.

The current collecting electrode 20 and the take-out electrode 21 are made of a ribbon-like copper foil and a plating layer provided around it.
Although it does not specifically limit as thickness of copper foil, For example, it is 30-300 [micrometer], The width is not specifically limited, For example, you may be 0.1-10 [mm].
The plated layer is made of a material such as Ag (silver), Sn (tin), or Cu (copper), and the thickness is not particularly limited, but is set to 1 to 100 [μm], for example.

The covering substrate 40 is disposed so as to cover the solar cell 10, the collecting electrode 20, and the extraction electrode 21 through the seal member 30. The coated substrate 40 is provided with an opening 40a, and the other end 21b of the extraction electrode 21 is drawn out through the opening 40a.
The coated substrate 40 only needs to be formed of a durable insulating material such as glass or transparent resin.

  Examples of the material constituting the sealing member 30 include, for example, vinyl chloride resin; polyethylene; polypropylene; polyethylene resin such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene naphthalate (PBN), and triacetyl cellulose ( TAC); ethylene-vinyl acetate copolymer (EVA) or the like can be used.

Next, the manufacturing method of such a solar cell module 1 is demonstrated.
3-12 is a figure explaining the manufacturing method of the solar cell module 1 of this invention, FIG.3,5,7,9,11,13 is a perspective view, FIG.4, 6,8,10,12 is shown. These are sectional views taken along line XX in FIGS. 3, 5, 7, 9, and 11, respectively.
In the method for manufacturing the solar cell module 1 of the present invention, the photoelectric converter 12, the collector electrode 20, and the extraction electrode 21 are arranged on one surface of the substrate 11, and then on the photoelectric converter 12. The process A of providing the sheet-like seal member 30 having a plurality of notches 31 over a part or the entire surface, and the process B of providing the cover substrate 40 on the seal member 30 are at least in order. It is characterized by this.

  The solar cell 10 can be manufactured according to a known method. For example, the photoelectric conversion body 12 is formed by laminating the first electrode layer 13, the semiconductor layer 14, and the second electrode layer 15 in this order on the one surface 11 a of the substrate 11. In addition, the thickness of each layer is the same as that of the conventional solar cell.

  As shown in FIG. 3, the photoelectric conversion body 12 is usually divided into a large number of partition elements 12 a having, for example, a strip shape by a scribe line 19. The partition elements 12a are electrically partitioned from each other, and are electrically connected in series, for example, between the partition elements 12a adjacent to each other. Thereby, the photoelectric conversion body 12 becomes the form which connected all the many division elements 12a electrically in series, and can take out electricity with a high electric potential difference. The scribe line 19 may be formed, for example, by forming the photoelectric conversion body 12 uniformly on the one surface 11a of the substrate 11 and then forming grooves in the photoelectric conversion body 12 at a predetermined interval with a laser or the like. Moreover, you may laminate | stack a protective layer on the 2nd electrode layer 15 as needed.

Next, the collector electrode 20 is disposed on the second electrode layer 15 constituting the photoelectric conversion body 12.
As shown in FIG. 3 and FIG. 4, a pair of collector electrodes 20 is disposed on the second electrode layer 15 of the partition element 12 a located at both ends of the plurality of partition elements 12 a via, for example, solder (not shown). Are electrically connected. A general soldering iron is used for connection. The collector electrode 20 is composed of a ribbon-like copper foil and a plating layer provided around the ribbon-like copper foil, and is arranged in parallel with the extending direction of the partition element 12a.

Next, the extraction electrode 21 is disposed on the second electrode layer 15 constituting the photoelectric conversion body 12.
As with the collecting electrode 20, the extraction electrode 21 is composed of a ribbon-like silver foil and a plating layer provided around it.
First, as shown in FIGS. 5 and 6, a protective sheet 22 and an insulating sheet 24 are arranged on the photoelectric conversion body 12 (second electrode layer 15) in the center of the cell.
Further, as shown in FIGS. 7 and 8, an insulating sheet 25 is disposed on the photoelectric conversion body 12 (second electrode layer 15), and an extraction electrode 21 is disposed on the insulating sheet 25.
The material of the insulating sheets 24 and 25 is preferably a resin, and more preferably a synthetic resin. Examples of preferable synthetic resins include silicon resins, fluororesins, and polyimide resins. The insulating sheets 24 and 25 may be known ones, and commercially available products may be used.
In addition, one end 21 a of the extraction electrode 21 is electrically connected to the current collecting electrode 20. For this connection, solder may be used, or connection may be made by melting the plating layers of the collecting electrode 20 and the extraction electrode 21 using an ultrasonic soldering iron or the like. On the other hand, the other end 21 b of the extraction electrode 21 is bent so as to rise from the photoelectric conversion body 12.

Next, the sealing member 30 is formed so as to cover the solar cell 10.
In particular, in this embodiment, as shown in FIGS. 9 and 10, the sheet-like sealing member 30 having a plurality of cutout portions 31 is provided on the photoelectric converter 12 (step A). In the present embodiment, a seal member 30 having a plurality of cutout portions 31 is used at a portion corresponding to at least a part of the extraction electrode 21 and its vicinity.
Since the seal member 30 having a plurality of notches 31 is used, the thickness of the extraction electrode 21 can be absorbed by the seal member 30. As a result, stress on the substrate due to the thickness of the extraction electrode 21 is less likely to occur inside the solar cell module, and the generated stress is alleviated.
The sealing member 30 may be a stack of a plurality of sheets instead of a single sheet. In that case, it is good also as a structure which has the some notch part 31 only in the one part sheet | seat among the laminated | stacked sheets. That is, as the seal member 30, a sheet having the notch portion 31 and a sheet not having the notch portion 31 may be used in an overlapping manner.
Such a sealing member 30 is preferably soft, and this softness is appropriately described by physical, Young's modulus, elastic modulus, viscosity coefficient, fluidity, and the like.
At this time, the other end 21b of the extraction electrode 21 is extended to the outside of the seal member 30 through the opening 30a.

  The notch 31 may be, for example, a part that is hollowed out in the thickness direction of the seal member 30 or a hole that penetrates the seal member 30. In the present embodiment, a case where a through hole is provided as the notch 31 is shown.

  Further, the shape and size of the cutout portion 31 are not particularly limited, but when the shape of the cutout portion is, for example, a circular shape, if it is too large, for example, in the step C described later, the sealing member 30 is used. When it is melted, it becomes difficult to fill the notch 31 with the melted sealing member 30. On the other hand, if it is too small, the thickness of the extraction electrode 21 cannot be absorbed, and the effect of the present invention is obtained. I can't. Therefore, it is preferable that the size of the notch is, for example, a hole shape of about φ1 to 5 mm or a strip shape of about 5 × 50 mm.

Further, in the sealing member 30 of the cutout portion 30, the area ratio with respect to the portion corresponding to at least a part of the extraction electrode 21 and the vicinity thereof needs to be an area that can ensure sufficient adhesiveness. It is preferable to be about 5 to 70%.
The thickness of such a seal member 30 is, for example, about 50 to 1600 μm as a thickness that ensures prevention of moisture intrusion.

Next, as shown in FIGS. 11 and 12, the coated substrate 40 is provided on the seal member 30 (step B).
At this time, the other end 21 b of the extraction electrode 21 is extended to the outside of the coated substrate 40 through the sealing member 30 and the opening 40 a provided in the coated substrate 40.

Moreover, after the step B, the sealing member 30 may be melted and the photoelectric conversion body 12 may be sealed with the sealing member 30 (step C). At this time, the notch 31 of the seal member 30 is filled with the melted seal member 30 (see FIGS. 1 and 2).
The sealing member 30 can be melted by, for example, a vacuum lamination method, an autoclave pressurization / heating method, or the like.
As described above, the coated substrate 40 is fixed on the photoelectric conversion body 12, and the manufacture of the solar cell module 1 is completed.

  As described above, in the present invention, since the seal member 30 having a plurality of notches 31 is used, the thickness of the extraction electrode 21 can be absorbed by the seal member 30. As a result, stress on the substrate due to the thickness of the extraction electrode 21 is less likely to occur inside the solar cell module, and the generated stress is alleviated. As a result, in this invention, the crack of the board | substrate 11 is prevented and the quality solar cell module 1 can be manufactured simply.

  In the above-described embodiment, the seal member 30 is a member provided with a plurality of the cutout portions 31 at portions corresponding to at least a part of the extraction electrode 21 and the vicinity thereof. However, the present invention is not limited to this, and the sealing member 30 may be a member provided with a plurality of the cutout portions 31 over the entire surface as shown in FIG.

As mentioned above, although the solar cell module and its manufacturing method of this invention were demonstrated, this invention is not limited to this, In the range which does not deviate from the meaning of invention, it can change suitably.
For example, the solar cell module of the present invention is not limited to those illustrated in the drawings, and a part of the configuration may be appropriately changed within a range not impairing the effects of the present invention.
In the embodiment described above, the protective sheet and the insulating sheet are disposed between the photoelectric conversion body and the extraction electrode, but the protective sheet and the insulating sheet may be omitted.

  Although the present invention has been described in detail with respect to an example applied to an amorphous silicon type (using thin film silicon) solar cell module, the solar cell may be a known one, for example, an amorphous type, a microcrystal type, a multi-junction type And so on. Moreover, although a solar cell (cell) is replaced with a silicon system, a compound system (III-V group multijunction, CIGS, CdTe, etc.), an organic system (dye sensitization, an organic semiconductor), etc. can be illustrated, but it is not limited to these. .

  DESCRIPTION OF SYMBOLS 1 Solar cell module, 10 solar cell, 11 board | substrate, 11a one surface, 12 photoelectric conversion bodies, 13 1st electrode layer, 14 semiconductor layer, 15 2nd electrode layer, 20 Current collection electrode, 21 Extraction electrode, 21a One end, 21b etc. End, 30 Seal member, 31 Notch, 40 Coated substrate.

Claims (4)

A solar cell in which a photoelectric conversion body in which at least a first electrode layer, a semiconductor layer, and a second electrode layer are stacked in this order is formed on one surface of a substrate;
A collector electrode disposed on the second electrode layer constituting the solar cell, and one end electrically connected to the collector electrode and disposed on the second electrode layer constituting the solar cell. An extraction electrode;
A sealing member disposed on one surface of the substrate so as to cover at least the photoelectric converter;
A coated substrate disposed on the sealing member, and a manufacturing method of a solar cell module comprising:
After providing the photoelectric conversion body, the current collecting electrode and the take-out electrode on one surface of the substrate,
Step A of providing the sheet-like sealing member having a plurality of notches on at least a part or the entire surface on the photoelectric converter;
Step B of providing the coated substrate on the seal member;
At least in order. The manufacturing method of the solar cell module characterized by the above-mentioned.   2. The process A according to claim 1, wherein, in the step A, the seal member is a member provided with a plurality of the cutout portions in a portion corresponding to at least a part of the extraction electrode and the vicinity thereof. A method for manufacturing a solar cell module.   3. The method according to claim 1, further comprising a step C of melting the sealing member after the step B, sealing the photoelectric conversion body with the sealing member, and filling the notch portion. The manufacturing method of the solar cell module of description.   The thickness of the said sealing member is 50 micrometers-1600 micrometers, The manufacturing method of the solar cell module as described in any one of Claim 1 thru | or 3 characterized by the above-mentioned.

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