JPH0590625A - Manufacture of solar battery - Google Patents

Abstract

PURPOSE:To provide the manufacture of a solar battery with little possibility of damaging a photoelectric conversion layer and composed of a simple process. CONSTITUTION:A molded sheet 1 formed by lamination of a photoelectric conversion layer on a substrate film at least via fusing inhibitor and further by lamination of a bonding layer is arranged on the inner peripheral face 13a of the cavity of a molding machine. After that, a resin material constituting a support 29 is packed into the cavity. When the support 29 is molded, the photoelectric conversion layer adheres to the support 29 by the conversion layer and a solar cell, where the photoelectric conversion layer is an integral part of the support 29, is obtained accordingly. At the time of molding, a force from resin is exerted so that stress is generated in the molded sheet 1, but a fusing inhibition layer prevents the fusion of the substrate film and photoelectric conversion layer. Therefore, even if the substrate film is deformed by the force from resin, a force applied to the photoelectric conversion layer is eased due to the deformation so that stress generated in the photoelectric conversion layer becomes smaller and the possibility of causing damage such as crack to the photoelectric conversion layer decreases too.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a solar cell in which a photoelectric conversion layer is supported by a support.

[0002]

2. Description of the Related Art For example, amorphous silicon (a-S)
i) Since a solar cell can be formed on a substrate made of various kinds of materials such as glass, metal, and resin, a curved film solar cell can be formed by forming an amorphous silicon solar cell on a substrate film made of a resin that is easily curved. Such as creating
Some solar cells have been applied to simple shaped products with a slight curvature. However, in film solar cells, the characteristics of the material used for the base film are both required in terms of the manufacturing process for forming the photoelectric conversion layer and the characteristics required for products supplied to the market, and both characteristics are satisfied. Selection of resin material is difficult. Therefore, conventionally, the following solar cell manufacturing method has been proposed.

That is, according to the conventional method, a base film for forming a photoelectric conversion layer and a film (support) used as a product
, And a material suitable for laminating the photoelectric conversion layer is used for the base film, and a material having characteristics as a product is used for the support. Then, first, the photoelectric conversion layer is laminated on the base film, and then the base film is cut into a predetermined shape. The photoelectric conversion layer side of the cut base film is adhered to a support formed into a product shape with an adhesive. Thus, a solar cell in which the photoelectric conversion element is bonded to the support is manufactured. The reason why the base film is cut in advance is to reduce the stress generated in the base film when the base film is pressed and adhered to the support, and thus the stress generated in the photoelectric conversion layer. Since the generated stress is small, the photoelectric conversion layer is less susceptible to damage such as cracking. This conventional method has an advantage that the materials for the base film and the support can be selectively used, and the materials can be easily selected.

[0004]

However, in the above-mentioned conventional manufacturing method, the manufacturing process is complicated such as the step of cutting the base film into a predetermined shape and the step of pressing and adhering the cut base film to the support. There is. Further, although the stress generated in the base film is reduced by cutting the base film, when the base film is pressed against the support, the photoelectric force of the base film may be generated by the component force of the pressing force depending on the shape of the surface of the support. Large stress is generated in the conversion layer. Therefore, the possibility that the photoelectric conversion layer is damaged, such as cracking, has not been sufficiently solved.

An object of the present invention is to solve the above problems and to provide a method for manufacturing a solar cell which has a small possibility of damage to the photoelectric conversion layer and which comprises simple steps.

[0006]

A method for manufacturing a solar cell according to the present invention is a method for manufacturing a solar cell in which a photoelectric conversion layer having electrodes on both sides of a photoelectric conversion element is supported by a support. A molding sheet formed by laminating the photoelectric conversion layer with at least a fusion preventing agent and further laminating an adhesive layer on the inner surface of the cavity of the molding machine.
A method for manufacturing a solar cell, comprising molding the support by filling the cavity with a resin material forming the support.

In the above structure, the molding sheet is placed on the inner peripheral surface of the cavity of the molding machine, and then the cavity is filled with the resin material forming the support body to mold the support body.
This is a simple process, but when the support is molded into a cavity shape, the photoelectric conversion layer is adhered to the support by the adhesive layer, and thus a solar cell in which the photoelectric conversion layer is integrated with the support is manufactured. .. Further, at the time of molding, stress is generated in the molded sheet due to the force from the resin, but the fusion preventing layer prevents fusion between the base film and the photoelectric conversion layer. Therefore, even if the base film is deformed by the force from the resin,
This deformation relaxes the force acting on the photoelectric conversion layer.
As a result, the stress generated in the photoelectric conversion layer is suppressed to a low level, and the possibility of damage such as cracking in the photoelectric conversion layer is reduced.

[0008]

EXAMPLES Examples of the present invention will be described below. The manufacturing method of the embodiment is to manufacture a solar cell by injection molding. (First Embodiment) The sectional view of FIG. 1 shows the structure of a molding sheet to be loaded into an injection molding machine. The molded sheet 1 has a structure in which a fusion preventing layer 5, a peeling layer 7, a photoelectric conversion layer 9, and an adhesive layer 11 are laminated on a base film 3 in this order.

As the base film 3, a biaxially stretched plastic film is used as a plastic film which exhibits plasticity with respect to the heat quantity and injection pressure of the molten resin in the injection molding process. Examples of the film used as the biaxially stretched plastic film include a biaxially stretched polyester film, a biaxially stretched nylon film, and a laminated film of these biaxially stretched polyester film and biaxially stretched nylon film. The thickness of the base film 3 varies depending on the shape of the molded product, but is 20 μm to 100 μm.
It is about m. It is preferably about 25 to 75 μm.

The fusion preventing layer 5 is composed of a fusion preventing agent. As the anti-fusion agent, a substance that hardens by crosslinking can be used, and for example, a thermosetting resin such as a melanin resin, a urea resin, an epoxy resin, a thermosetting acrylic resin, or a urethane resin can be used. The peeling layer 7 is composed of a peeling agent (release agent) that facilitates peeling between the base film 3 and the photoelectric conversion layer 9.

The photoelectric conversion layer 9 forms a transparent conductive film (electrode) on which a p-layer of amorphous or microcrystalline or polycrystalline material,
After a pin photoelectric conversion element in which i layers and n layers are sequentially laminated, or one or a plurality of nip photoelectric conversion elements are laminated,
Further, electrodes are formed. The material used for the photoelectric conversion element is a-Si: H, a-SiC: H, a-Ge:
There are amorphous materials such as H, and these materials are formed on the peeling layer 7 by the plasma CVD method. A material obtained by adding trivalent ions such as boron and aluminum to the amorphous material is used for the p layer of the amorphous material. A material obtained by adding pentavalent ions such as phosphorus and arsenic to an amorphous material is used for the n layer of the amorphous material.

The adhesive layer 11 has a softening point lower than the melting temperature (here, 230 ° C.) of the molding resin (here, ABS resin) used during injection molding, and it melts with the molding resin to heat the molding resin. Adhesive materials are used. As such a material, a material containing a styrene resin, a thermoplastic acrylic resin, a polycarbonate, a vinyl chloride / vinyl acetate polymer, a polyamide resin, a polyester resin, a chlorine value polyolefin or the like as a main component is used. A colorant or an auxiliary agent may be appropriately added.

The following molded sheet 1 was manufactured as the molded sheet 1 having the above structure. That is, a fusion preventing layer 5 having a thickness of 2 μm was formed on a base film 3 made of a biaxially stretched polyester film by an gravure coating method using an ink layer having the composition described below, and the fusion preventing layer 5 was formed at an ambient temperature of 180 ° C. for 20 minutes. After curing for 2 seconds, a release agent layer was formed thereon as a release layer 7 by a gravure printing method using an ink having the composition described below. Next, in a vacuum device, the transparent conductive film I
TO (indium tin oxide) was deposited. And, n layer a-Si, i layer a-Si: H, p layer a-Si
C: H was formed using a plasma CVD apparatus, and then a transparent conductive film was deposited to form a photoelectric conversion layer 9. Further, an adhesive layer 11 was formed thereon by an gravure coating method using an ink having the composition described below. Thus, a molded sheet 1 was obtained. Typical compositions are shown below. Composition of anti-fusing layer Urea resin (mixture of urea and formaldehyde) 60 parts by weight Epoxy resin 20 parts by weight CAB (cellulose acetate butyrate) 20 parts by weight Acid catalyst (curing agent) 20 parts by weight Methanol / MEK (methyl ethylene ketone) mixed at a ratio of 4: 1 200 parts by weight Composition of release layer Thermoplastic acrylic resin ...... 70 parts by weight Vinyl chloride vinyl acetate copolymer resin ...... 30 parts by weight Polyethylene wax ...... 3 parts by weight Mixture of toluene / MEK mixed at a ratio of 1: 1 ...... 200 parts by weight Composition of adhesive layer ABS resin ...... 50 parts by weight Pigment ...... 20 parts by weight Toluene / ethyl acetate 3: 7 Mixture mixed in proportion: 200 parts by weight Next, an injection molding machine for setting the molding sheet 1 will be described.

The sectional view of FIG. 2 shows the essential parts of the injection molding machine in the mold open state. The molding sheet 1 described above is arranged between the movable side mold plate 13 and the fixed side mold plate 15. The molded sheet 1 is set so that the base film 3 of the molded sheet 1 faces the movable-side template 13 and the laminated portion of the photoelectric conversion layer 9 and the like faces the fixed-side template 15. This molded sheet 1 is a sheet roll 1
The molded sheet 1 wound around the sheet roll 7 and pulled out from the sheet roll 17 passes between the movable-side mold plate 13 and the fixed-side mold plate 15 and is wound up by the winding roll 19. In addition, the molded sheet 1 is a push roll 2 arranged on the sheet roll 17 side.
1 and the driving roll 23, and the pushing roll 25 and the driving roll 27 arranged on the winding roll 19 side. The winding / positioning control of the molded sheet 1 is performed by the rotation control of the winding roll 19 and the drive rolls 23 and 27. The push rolls 21 and 25 press the molded sheet 1 toward the drive rolls 23 and 27 to apply an appropriate tension to ensure the winding / positioning control of the molded sheet 1.

This injection molding machine operates as follows.
In the mold open state shown in FIG. 2, first, the molded sheet 1 is wound and positioned. In positioning, the laminated portion of the photoelectric conversion layer 9 and the like of the molded sheet 1 has a cavity inner peripheral surface 13 a of the movable side template 13 and a cavity inner peripheral surface 15 of the fixed side template 15.
It is arranged at a predetermined position between a and a in consideration of the design content of the final product (solar cell).

Next, the mold is clamped as shown in FIG.
The molded sheet 1 stretched with an appropriate tension is arranged exactly along the inner peripheral surface 13a of the cavity of the movable side mold plate 13 formed by the male mold. Then, the ABS resin 29 melted at 230 ° C. is injected from the gate 15b into the cavity as a molten resin forming the support.

When the ABS resin 29 injected into the cavity is molded into a cavity shape, the photoelectric conversion layer 9 is adhered to the ABS resin by the adhesive layer 11. Further, during molding, the molded sheet 1 is pulled by the flow of resin, but since the fusion preventing layer 5 prevents fusion between the base film 3 and the photoelectric conversion layer 9, the base film 3 is made of resin. Even when it is deformed by the force of, the force acting on the photoelectric conversion layer 9 is relaxed by this deformation. In particular, the relaxation of the force acting on the photoelectric conversion layer 9 becomes remarkable in the three-dimensional shape where the force from the resin flow is large and the unevenness is largely changed or at the R portion. Therefore, the stress generated in the photoelectric conversion layer 9 is suppressed to a low level, and the possibility that the photoelectric conversion layer 9 is damaged such as cracks during molding is significantly reduced.

After cooling, the mold is opened as shown in FIG. At the time of mold opening, the take-up / positioning mechanism (sheet roll 17, take-up roll 19, etc.) of the molded sheet 1 is separated from the fixed-side mold plate 15, so that the base sheet 3 is made of ABS resin by the function of the release layer 7. The molded product of No. 29 is separated from the photoelectric conversion layer 9 which is already integrated.

The solar cell thus manufactured is shown in the perspective view of FIG. This solar cell 30 has a photoelectric conversion layer 9 integrated with a three-dimensionally shaped ABS resin support 29 that is curved in one direction. The surface of the photoelectric conversion layer 9 is flush with the surface of the ABS resin molded product. The energy conversion efficiency of this solar cell 30 was 5.5 [%].

According to the method for manufacturing a solar cell described above, the molding sheet 1 with the fusion preventing layer 5 interposed is placed on the cavity inner peripheral surface 13a of the injection molding machine, and then the ABS resin 29 is placed in the cavity. The solar cell 30 can be manufactured by a simple process of injecting and molding the support, and the possibility that the photoelectric conversion layer 9 is damaged such as cracks is significantly reduced. Of course, since the ABS resin support 29 is molded by injection molding, it is possible to manufacture a solar cell having a support 29 having a complicated three-dimensional shape.

Further, since the surface of the ABS resin support 29 and the surface of the photoelectric conversion layer 9 are flush with each other, there is an advantage that the solar cell 30 which is not easily scratched and has an excellent appearance can be manufactured. (Second Embodiment) This embodiment is a method of manufacturing a solar cell by injection molding similarly to the first embodiment, but is characterized by not peeling the base film.

The sectional view of FIG. 6 shows the structure of the molded sheet 41. The molded sheet 41 is formed by laminating a fusion preventing layer 45, a photoelectric conversion layer 47, and an adhesive layer 49 on a base film 43 in this order.
The base film 43 is a plastic film exhibiting plasticity with respect to the heat quantity and the injection pressure of the molten resin in the injection molding process, as in the base film 3 of the first embodiment.
Axial stretched plastic film is used. The anti-fusing layer 45 is made of an anti-fusing agent, like the anti-fusing layer 5 of the first embodiment. Similarly to the photoelectric conversion layer 9 of the first embodiment, the photoelectric conversion layer 47 also has a transparent conductive film formed thereon, and a p-layer, an i-layer, and an n-layer of amorphous or microcrystalline or polycrystalline material are sequentially stacked on the transparent conductive film. This is one in which a pin photoelectric conversion element or a nip photoelectric conversion element is laminated in one layer or a plurality of layers and then an electrode is formed. As the adhesive layer 49, the adhesive layer 11 of the first embodiment is used.
Similarly to the above, a material having a softening point lower than the melting temperature of the molding resin used at the time of injection molding and being melted with the molding resin to be thermally bonded to the molding resin is used.

In the second embodiment, the following molded sheet 41 was manufactured. That is, a fusion preventing layer 4 having a thickness of 2 μm is formed by a gravure coating method using an ink layer having the composition described below on a base film 43 made of a biaxially stretched polyester film.
5 was formed and cured at an ambient temperature of 180 ° C. for 20 seconds. Next, in a vacuum device, the transparent conductive film ITO
(Indium tin oxide) was deposited. And
n layer a-Si, i layer a-Si: H, p layer a-SiC: H
Was formed using a plasma CVD apparatus, and a transparent conductive film was subsequently deposited to form a photoelectric conversion layer 47. Further, an adhesive layer 49 was formed thereon by an gravure coating method using an ink having the composition described below. Thus, a molded sheet 41 was obtained. A typical composition is as follows. Composition of anti-fusing layer Urea resin (mixture of urea and formaldehyde) 60 parts by weight Epoxy resin 20 parts by weight CAB (cellulose acetate butyrate) 20 parts by weight Acid catalyst (curing agent) 20 parts by weight Methanol / MEK (methyl ethylene ketone) mixed at a ratio of 4: 1 200 parts by weight Composition of adhesive layer ABS resin 50 parts by weight Pigment 20 parts by weight Toluene / ethyl acetate 3: 7 Mixture mixed in proportion: 200 parts by weight Next, an injection molding machine in which the molding sheet 1 is set will be described.

The sectional view of FIG. 7 shows the essential parts of the injection molding machine in the mold open state. The molding sheet 41 is arranged between the movable side mold plate 51 and the fixed side mold plate 53. The base film 43 of the molded sheet 41 faces the movable side mold plate 51 side, and the photoelectric conversion layer 47
The molding sheet 41 is set so that the laminated portion such as facing the stationary side template 53. The formed sheet 41 is wound around a sheet roll 57, and the formed sheet 57 pulled out from the sheet roll 57 has a movable side template 51 and a fixed side template 5.
It is taken up by the take-up roll 57 after passing through the gap between the rolls 3 and 3. Further, the formed sheet 41 is guided by a pressing roll 61 and a driving roll 63 arranged on the sheet roll 57 side, and a pressing roll 65 and a driving roll 67 arranged on the winding roll 59 side. The winding / positioning control of the formed sheet 41 is performed by the rotation control of the winding roll 59 and the drive rolls 63 and 27. The pressing rolls 61 and 65 press the forming sheet 41 toward the driving rolls 63 and 67 to apply an appropriate tension to ensure the winding / positioning control of the forming sheet 41.

On the movable side mold plate 51 of this injection molding machine, a cutter 55 surrounding the upper mold (male mold) is housed in the housing portion 51a. The cutter 55 moves in and out of the template surface by an actuator (not shown). This injection molding machine operates as follows.

In the mold open state shown in FIG. 7, first, the molded sheet 41 is wound and positioned. In positioning,
The laminated portion of the photoelectric conversion layer 47 and the like of the molding sheet 41 includes the cavity inner peripheral surface 51b of the movable side template 51 and the fixed side template 53.
It is placed at a predetermined position in consideration of the design content of the final product (solar cell) between the inner peripheral surface 53a of the cavity.

Next, the mold is clamped as shown in FIG.
The molded sheet 41 stretched with an appropriate tension is used for the movable side mold plate 13
It is arranged exactly along the inner peripheral surface 51b of the cavity formed by the male mold. Subsequently, ABS resin 69 melted at 230 ° C. was used as a molten resin constituting the support from the gate.
Is injected into the cavity.

When the ABS resin 69 injected into the cavity is molded into the shape of the cavity, the adhesive layer 4 is applied to the ABS resin.
The photoelectric conversion layer 47 is adhered by 9. Further, during molding, the molded sheet 1 is pulled by the flow of resin, but since the fusion preventing layer 5 prevents fusion between the base film 3 and the photoelectric conversion layer 9, the base film 3 is made of resin. Even when it is deformed by the force of, the force acting on the photoelectric conversion layer 9 is relaxed by this deformation. Especially in the three-dimensional shape where the force from the resin flow is large and the unevenness is large or at the R part,
The relaxation of the force acting on the photoelectric conversion layer 47 becomes remarkable. Therefore, the stress generated in the photoelectric conversion layer 47 is suppressed to a low level, and the possibility that the photoelectric conversion layer 47 is damaged such as cracks during molding is significantly reduced.

Next, as shown in FIG. 9, the cutter 55 is taken out from the surface of the movable side mold plate 51 and the base film 43 around the cavity is punched out. After cooling, the mold is opened as shown in FIG. When the winding / positioning mechanism (sheet roll 57, winding roll 59, etc.) for the molded sheet 1 separates from the fixed-side mold plate 53 during mold opening, the base film 3 separates and the three-dimensional ABS resin support 69 is formed. A solar cell in which the photoelectric conversion layer 47 is integrated is obtained. Photoelectric conversion layer 47 of solar cell
On the side, a punched substrate film 43 covers the surface. The energy conversion efficiency of this solar cell 30 is 5.8.
[%]Met.

According to the method of manufacturing a solar cell described above, in addition to the effect of the first embodiment, a solar cell in which the photoelectric conversion layer 47 is protected by the base film 43 covering the surface can be easily manufactured. Produce an effect. Although the base film 43 constitutes a part of the product (solar cell), the ABS resin carries the required properties (strength, etc.) as a support, so the material of the base film 43 is selected as the base film itself. It is still much easier than using a support.

FIG. 11 illustrates a solar cell 70 which can be manufactured by the first and second embodiments described above. According to each embodiment, the solar cell 70 in which the photoelectric conversion layer 73 is integrated with the support 71 having such a complicated three-dimensional shape can be easily manufactured. Although the embodiments have been described above, the present invention is not limited to the embodiments, and it goes without saying that the present invention can be implemented in various modes without departing from the spirit of the present invention. For example, in addition to injection molding machines, blow molding machines,
Various other molding methods may be used, such as using a compression molding machine or a transfer molding machine. In addition, in the embodiment, the molded sheet 1 is arranged such that the base film 3 faces the cavity inner peripheral surface 13a and the laminated portion of the photoelectric conversion layer 9 and the like faces the gate 15b. Molding may be performed by arranging the molding sheet 1 so that the laminated portion such as the layer 9 faces the cavity 13a and the base film 3 faces the gate 15b. In this case, since the base film 3 protects the photoelectric conversion layer 9 from the resin with which the cavity is filled, it is expected that the force acting on the photoelectric conversion layer 9 will be further alleviated.

[0032]

According to the method of manufacturing a solar cell of the present invention described in detail above, a molding sheet having a fusion preventing layer interposed is disposed on the inner peripheral surface of the cavity of a molding machine, and then the support is placed in the cavity. It is possible to manufacture a solar cell by a simple process of filling the resin material constituting the substrate and molding the support, and further, it is possible to reduce the risk of damage such as cracking in the photoelectric conversion layer.

[Brief description of drawings]

FIG. 1 is a sectional view showing the structure of a molded sheet used in a first embodiment of the present invention.

FIG. 2 is a sectional view showing a main part of an injection molding machine used in the first embodiment.

FIG. 3 is a sectional view of a main part of an injection molding machine showing a state where resin is injected into a cavity.

FIG. 4 is a sectional view of an essential part of the injection molding machine showing a state where the mold is opened.

FIG. 5 is a perspective view illustrating a manufactured solar cell.

FIG. 6 is a cross-sectional view showing the structure of a molded sheet used in the second embodiment.

FIG. 7 is a cross-sectional view showing the main parts of an injection molding machine used in the second embodiment.

FIG. 8 is a sectional view of an essential part of the injection molding machine showing a state where resin is injected into the cavity.

FIG. 9 is a sectional view of an essential part of the injection molding machine showing a state in which a cutter is operated.

FIG. 10 is a sectional view of an essential part of the injection molding machine showing a state where the mold is opened.

FIG. 11 is a perspective view illustrating a manufactured solar cell.

[Explanation of symbols]

1, 41 ... Molded sheet, 3, 43 ... Substrate film, 5, 45 ... Fusion prevention layer, 9, 47 ... Photoelectric conversion layer, 11, 49 ... Adhesive layer, 29, 69 ... AB
S resin support, 30, 70 ... Solar cell,
71 ... Support, 73 ... Photoelectric conversion layer

Claims (1)

[Claims] 1. A method for manufacturing a solar cell in which a photoelectric conversion layer having electrodes provided on both sides of a photoelectric conversion element is supported by a support, wherein the photoelectric conversion layer is laminated on a base film with at least a fusion inhibitor. A molding sheet obtained by further laminating an adhesive layer is disposed on the inner peripheral surface of the cavity of the molding machine, and thereafter, the cavity is filled with the resin material constituting the support body to mold the support body. Method for manufacturing solar cell.