JPH11298020A - Thin-film solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin-film solar cell module, in which lighting and design are improved by covering a second electrode layer side with a backside sealing compound to form a solar cell module, by considering maximum planar area of a photoelectric conversion layer and a second electrode layer to be specific with respect to the output surface of a substrate, and by constructing the backside sealing compound with a transparent material. SOLUTION: First electrode layers 11-13 are formed on a transparent insulating substrate 3, and photoelectric conversion layers 21-23 are prepared on first electrode layers 11-13, respectively. Next, second electrode layers 31-33 are formed on photoelectric conversion layers 21-23 to form thin-film solar cell, respectively. EVA (ethylene-vinyl rotate copolymer) resin 2 is coated on a tempered glass 1 of surface plastic material, and is further coated with photo- detecting surface of the thin-film solar cells. EVA resin 4 and backside transparent sealing material are formed sequentially on the second electrode layer side 31-33 to form a thin-film solar cell module. It is so constituted that the maximum planar area of the photoelectric layers 21-23 and the second electrode layers 31-33 is 90-30% of the surface area of the transparent insulating film 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a thin-film solar cell module. More specifically, the present invention relates to a thin-film solar cell module having excellent lighting and design.

[0002]

2. Description of the Related Art For example, Japanese Unexamined Utility Model Publication No. Sho 60-63958, Japanese Unexamined Patent Publication No. Hei.
No. 923 describes a general thin-film solar cell module. General thin-film solar cell module 10
13 is a schematic perspective view of FIG. 13, and FIG. 14 is a schematic cross-sectional view of FIG. A method for manufacturing a thin-film solar cell module will be described below with reference to FIGS.

[0003] First, a first electrode layer is formed on almost the entire surface of the insulating substrate 8. In the case of FIG. 14, the first electrode layer is made of a transparent material so that light is incident from the insulating substrate 8 side. As the transparent material, SnO ₂ , ZnO, ITO and the like are often used. Next, the first electrode layer is patterned. In the case of FIG. 14, 100 μm at a pitch of about 10 mm
Linear dividing grooves 201, 202, and 203 having a width of about 1 mm are provided. As a patterning method, a chemical etching method, a mechanical marking method, or the like is used. In the above method, patterning is performed after forming the first electrode layer on the entire surface of the substrate. However, there is also a method in which film formation and patterning are performed simultaneously by laminating through a mask. By patterning, the first electrode layer is divided into a plurality of strip-shaped first electrode layers 101, 102, and 103.

Next, on the first electrode layer, a photoelectric conversion layer composed of one or more layers is formed over substantially the entire surface of the insulating substrate. With this film formation, the division grooves 201, 202, and 203 are also filled with the photoelectric conversion layer. After that, the photoelectric conversion layer is patterned. In the case of FIG. 14, in parallel with the dividing groove and at an interval of about 100 μm from the dividing groove,
Linear dividing grooves 211, 212 and 213 having a width of about 100 μm are provided. Thereby, the photoelectric conversion layer is divided into a plurality of strip-shaped photoelectric conversion layers 111, 112, and 113. As a patterning method, a chemical etching method, a mechanical marking method, or the like is used. Further, the layers may be stacked via a mask.

Next, a second electrode layer is formed on substantially the entire surface of the substrate on the photoelectric conversion layer. As the second electrode layer, a metal thin film having high reflectivity such as Ag or Al is used in order to effectively utilize light by reflection. After that, the second electrode layer is patterned. In the case of FIG. 14, linear division grooves 221 and 22 having a width of about 100 μm are parallel to the division grooves of the photoelectric conversion layer and at an interval of about 100 μm from the division grooves.
Patterning is performed to provide 2 and 223. As a result, the second electrode layer becomes a plurality of strip-shaped second electrode layers 12.
1, 122 and 123. As a patterning method, a chemical etching method, a mechanical marking method, or the like is used. Further, the layers may be stacked via a mask.

[0006] By performing the above-described film formation and patterning, the corresponding first electrode layer, photoelectric conversion layer, and second electrode layer are respectively laminated, thereby forming a thin-film solar cell. Further, the first electrode layer, the photoelectric conversion layer, and the second electrode layer are formed in a stepwise manner, and the division grooves 211, 212, and 213 are filled with the second electrode layer. Therefore, the first electrode layer of each thin-film solar cell is connected to the second electrode layer of an adjacent thin-film solar cell, so that a plurality of thin-film solar cells are connected in series with each other.

A thin-film solar cell module can be obtained by sealing a thin-film solar cell manufactured by the above-described manufacturing method with a tempered glass 6 for surface protection, adhesives 7 and 9, and a back sealing material 10. it can. In addition, an opaque material is generally used as the back surface sealing material. In the above-mentioned thin-film solar cell module, the thin-film solar cell is formed on the entire surface of the insulating substrate, and the back-side sealing material made of an opaque material is used, so that the amount of light transmitted to the back side is small,
Lighting was poor in principle.

In order to improve the daylighting properties, Japanese Patent Application Laid-Open No.
No. 259 describes a thin-film solar cell module in which a hole through which light passes is formed in the photoelectric conversion layer and the second electrode layer.

[0009]

SUMMARY OF THE INVENTION The above-mentioned Japanese Patent Application Laid-Open No. 5-152 is disclosed.
In the method of transmitting light by providing a hole as disclosed in JP-A-59-5959, since the method is performed after the formation of the thin-film solar cell module, it is necessary to separately provide a step of forming a hole. In addition, the design of the thin-film solar cell module is poorly changed and tends to be monotonous.

[0010]

Thus, according to the present invention, a plurality of solar cells are formed by laminating a transparent first electrode layer, a photoelectric conversion layer, and a second electrode layer in this order on a substrate, Furthermore, the solar cell module is covered with the back surface sealing material on the second electrode layer side, and the maximum area of the plane with the photoelectric conversion layer and the second electrode layer occupies 90 to 30% of the surface area of the substrate,
A thin-film solar cell module is provided, wherein the back surface sealing material is made of a translucent material.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The substrate that can be used in the present invention is not particularly limited, but is preferably a translucent insulating substrate. Specifically, a plate-like or film-like glass substrate, an organic substrate, and the like can be given. A plurality of thin-film solar cells are formed on the substrate. Each thin film solar cell has a configuration in which a transparent first electrode layer, a photoelectric conversion layer, and a second electrode layer are stacked in this order.

The material of the first electrode layer is not particularly limited, and any material known in the art can be used. Specifically, SnO ₂ , ZnO, ITO and the like can be mentioned. The first electrode layer is provided for each thin-film solar cell, and is separated from the first electrode layer of an adjacent thin-film solar cell. The planar shape of the first electrode layer is not particularly limited because the first electrode layer itself has a light-transmitting property. For example, a planar shape such as a stripe shape and an island shape is given. In addition, the thickness of the first electrode layer is usually 0.5 to 1 μm.

As a method for forming the first electrode layer, any method known in the art can be used. For example, a thermal CVD method, a MOCVD method, and the like can be given. Also,
As a method of forming a desired planar shape, a method of forming a first electrode layer using a mask covering a region where formation of the first electrode layer is not desired, or forming the first electrode layer on the entire surface of the substrate once After that, a method of separating by chemical etching, mechanical marking, laser or the like may be used. The first
Fine irregularities may be formed on the surface of the electrode layer in order to extend the optical path length. The fine irregularities appropriately reflect light transmitted through the thin-film solar cell module irregularly, and can suppress glare caused by the transmitted light.

Further, if the loss caused by the voltage drop when the current generated in the thin-film solar cell flows only in the first electrode layer becomes a problem, the metal along the current flowing path on the first electrode layer may be problematic. Films (for example, Ag films) may be stacked.
This metal film is preferably formed below the photoelectric conversion layer and the second electrode layer, which are formed later, from the viewpoint of improving light transmission.

The material for the photoelectric conversion layer is not particularly limited, and any material known in the art can be used. Specifically, single crystal silicon, amorphous silicon,
Polycrystalline silicon and the like can be given. Of these, amorphous silicon is preferred. The photoelectric conversion layer is usually composed of a plurality of layers, for example, formed on the first electrode layer in the order of a p-layer, an i-layer, and an n-layer. Here, the p layer is doped with impurities such as boron, and the n layer is doped with impurities such as phosphorus and arsenic. This photoelectric conversion layer is provided for each thin-film solar cell and is separated from the photoelectric conversion layer of an adjacent thin-film solar cell. The planar shape of the photoelectric conversion layer is not particularly limited as long as it accounts for 90% or less of the plane of the thin-film solar cell module. For example, a planar shape such as a stripe shape and an island shape is given. In addition, the thickness of the photoelectric conversion layer is usually 0.2 to 0.5 μm.

As a method for forming the photoelectric conversion layer, any method known in the art can be used. For example, a vapor deposition method, a plasma CVD method, and the like can be given. Also,
As a method of forming a desired planar shape, a method of forming a photoelectric conversion layer using a mask covering a region where formation of a photoelectric conversion layer is not desired, once forming the photoelectric conversion layer over the entire substrate, A method of separating by chemical etching, laser or the like can be used.

The material for the second electrode layer is not particularly limited, and any material known in the art can be used. Specifically, A having high conductivity and high reflectivity
g, metals such as Al. The second electrode layer is provided for each thin-film solar cell and is separated from the second electrode layer of an adjacent thin-film solar cell module. The planar shape of the second electrode layer is not particularly limited as long as the proportion occupying 90% or less of the plane of the thin-film solar cell module.
For example, a planar shape such as a stripe shape and an island shape is given. In addition, the thickness of the second electrode layer is usually 0.5 to 1 μm. Further, the second electrode layer may be connected to the first electrode layer so as to be in series or parallel with the adjacent thin film solar cell.

As a method for forming the second electrode layer, any method known in the art can be used. For example, a vapor deposition method, a plasma CVD method, and the like can be given. Also,
As a method of forming a desired planar shape, a method of forming a second electrode layer using a mask that covers a region where formation of the second electrode layer is not desired, or forming the second electrode layer once on the entire surface of the substrate After that, a method of separating by chemical etching, laser or the like may be used.

Next, in the present invention, the second electrode layer side
It is covered with a back surface sealing material via an adhesive. This back surface sealing material is made of a translucent material. Therefore, the lighting performance of the thin-film solar cell module is not hindered. Here, examples of the light-transmitting material include glass and fluorine-based resin. The adhesive for fixing the back surface sealing material is not particularly limited as long as it has good translucency. For example, ethylene vinyl acetate (EVA) resin and the like can be mentioned.

The substrate may be covered with a tempered glass or the like via an adhesive to protect the substrate. Furthermore, the thin-film solar cells may be connected in series and / or in parallel with adjacent cells. Further, the thin-film solar cell module may include an arbitrary number of thin-film solar cells as one group and a plurality of groups. In this case, the connection between cells in the group is preferably in series. Furthermore,
The connection between the groups may be connected in series and / or in parallel by the first electrode layer.

As described above, the thin-film solar cell module of the present invention comprises the photoelectric conversion layer and the second
The maximum area of the plane with the electrode layer is 90 to the surface area of the substrate.
It is 30%. Therefore, it is a thin-film solar cell module excellent in daylighting properties. Here, the maximum area of the plane is
It means a value obtained by subtracting the area of the plane of the overlapping portion of the two layers from the total value of the area of the plane of the photoelectric conversion layer and the second electrode layer. In addition, the maximum area of the plane of the photoelectric conversion layer and the second electrode layer is set to 9
Preferably it is 0-70%.

[0022]

The present invention will be specifically described below with reference to examples. Embodiment 1 An embodiment of the present invention will be described below with reference to FIGS.
On a translucent insulating substrate made of a glass substrate 3 having a thickness of 1.1 mm, an approximately 3 μm thick Sn
First electrode layers 11, 12 and 1 made of O ₂ (transparent material)
3 was formed by a thermal CVD method. The first electrode layers 11, 12 and 13 were formed at a pitch of 30 mm so as to be insulated from each other by linear dividing grooves having a width of about 100 μm. Further, fine irregularities were formed on the surface of the first electrode layer for the purpose of extending the optical path length.

Next, on each of the first electrode layers, photoelectric conversion layers 21, 22 and 23 were deposited by a plasma CVD method via a mask. As shown in FIG. 2, these photoelectric conversion layers were formed with an appropriate gap in the AA ′ direction of FIG. The photoelectric conversion layer was made of amorphous silicon, and was formed on the substrate in the order of p-layer, i-layer, and n-layer. The width of the photoelectric conversion layers 21, 22, and 23 was 10 mm, and the thickness of each layer of the photoelectric conversion layer was about 500 nm.

Next, the second electrode layers 31, 32 and 33 were deposited on each photoelectric conversion layer by a sputtering method or a vapor deposition method via a mask. A second electrode layer 31,
32 and 33 are made of Ag having a width of 10 mm and a film thickness of 500 nm. By doing so, as shown in FIG. 1, the thin-film solar battery cells could be formed on the glass substrate 3 at an interval from other adjacent cells. Further, the cells were interconnected by a first electrode layer.

Next, a thin-film solar cell module was prepared as follows using the thin-film solar cells manufactured by the above method. As a surface protection material, an EV having the same size as the tempered glass 1 is placed on a 3.2 mm-thick tempered glass 1 slightly larger than the glass substrate 3 of the thin-film solar cell.
A resin 2 was placed, and a thin-film solar cell was placed thereon with the glass substrate surface (light receiving surface) facing down. After attaching a lead wire to the cell so that the output of the thin-film solar cell can be taken out from both ends of the module, an EVA 4 having the same size as the tempered glass 1 and a light-transmitting back protective film (back sealing material) 5 are provided. Stacked. Next, it was put in a laminating apparatus and heat-bonded while performing degassing between the members. Thus, the thin-film solar cell module 100 shown in FIG. 1 was obtained.

In the case of Example 1, the maximum area of the photoelectric conversion layer and the second electrode layer in the plane of the module was 34%. Further, the transmitted light is appropriately irregularly reflected by the unevenness of the first electrode layer, so that glare caused by the transmitted light could be suppressed. The above thin-film solar cell module is converted into an effective power generation area under the irradiation light of AM1.5 to obtain Jsc =
15.0 mA / cm ² , Voc (per thin-film solar cell) = 0.90 V, F.V. F. = 0.72, Pmax
= 9.5 mW / cm ² , and the photoelectric conversion rate was 9.5%. It was found that the thin-film solar cell module of Example 1 had excellent translucency and design.

Embodiment 2 An embodiment of the present invention will be described below with reference to FIGS. The first electrode layers 41 and 4 are formed on the glass substrate 3 as in the first embodiment.
2 and 43 were formed via a metal mask.

Next, in the same manner as in the first embodiment, each of the first
On the electrode layer, photoelectric conversion layers 51, 52 and 53 were deposited by a plasma CVD method via a mask. However, as shown in FIG. 5 and FIG.
An appropriate gap was provided in the C ′ direction and the DD ′ direction.

Next, in the same manner as in Example 1, second electrode layers 61, 62 and 63 were deposited on each of the photoelectric conversion layers via a mask. In this way, as shown in FIG. 4, thin-film solar cells could be formed on the glass substrate 3 with an interval from other adjacent cells.

Next, a thin-film solar cell module was prepared as follows using the thin-film solar cell produced by the above method. As a surface protection material, a 3.2 m thick, slightly larger than the glass substrate 3 of the thin-film solar cell
The EVA resin 2 having the same size as the tempered glass 1 was placed on the tempered glass 1 of m, and the thin-film solar cell was further placed thereon with the glass substrate surface (light receiving surface) facing down. After attaching a lead wire to the cell so that the output of the thin-film solar cell can be taken out from both ends of the module, an EVA 4 having the same size as the tempered glass 1 and a light-transmitting back protective film (back sealing material) 5 are provided. Stacked. Next, it was put in a laminating apparatus and heat-bonded while performing degassing between the members. Thus, a thin-film solar cell module 100 as shown in FIG. 4 was obtained.

The above-mentioned thin-film solar cell module has the AM1.
Under the irradiation light of No. 5, Js
c = 15.0 mA / cm ² , Voc (per thin-film solar cell) = 0.90 V, F.C. F. = 0.72, Pm
ax = 9.5 mW / cm ² , and photoelectric conversion efficiency = 9.5%. The thin-film solar cell module of Example 2 had better translucency than the module of Example 1.

Embodiment 3 An embodiment of the present invention will be described below with reference to FIGS. The first electrode layers 71 and 7 are formed on the glass substrate 3 as in the first embodiment.
2, 73, 74, 75 and 76 were formed via a metal mask. However, these first electrode layers 71, 72, 73,
74, 75 and 76, as shown in FIG.
It was formed so as to provide an appropriate gap in the F 'direction.

Next, in the same manner as in the first embodiment, each of the first
On the electrode layers, the photoelectric conversion layers 81, 82, 83, 84, 85
And 86 were deposited by a plasma CVD method through a mask. However, as shown in FIGS. 8 and 9, the photoelectric conversion layer was formed with an appropriate gap provided in the FF ′ and EE ′ directions in FIG.

Next, the second electrode layers 91, 92, 93, 94, 95 are formed on the respective photoelectric conversion layers in the same manner as in the first embodiment.
And 96 were deposited through a mask. In this way, as shown in FIG. 7, a plurality of groups in which three thin-film solar cells are integrated on the glass substrate 3 can be formed, and a predetermined interval is formed between adjacent groups. ing.

Next, a thin-film solar cell module was prepared as follows using the thin-film solar cell produced by the above method. As a surface protection material, a 3.2 m thick, slightly larger than the glass substrate 3 of the thin-film solar cell
The EVA resin 2 having the same size as the tempered glass 1 was placed on the tempered glass 1 of m, and the thin-film solar cell was further placed thereon with the glass substrate surface (light receiving surface) facing down. After attaching a lead wire to the cell so that the output of the thin-film solar cell can be taken out from both ends of the module, an EVA 4 having the same size as the tempered glass 1 and a light-transmitting back protective film (back sealing material) 5 are provided. Stacked. Next, it was put in a laminating apparatus and heat-bonded while performing degassing between the members. Thus, a thin-film solar cell module 100 as shown in FIG. 7 was obtained.

The above thin-film solar cell module has the AM1.
Under the irradiation light of No. 5, Js
c = 15.0 mA / cm ² , Voc (per thin-film solar cell) = 0.90 V, F.C. F. = 0.72, Pm
ax = 9.5 mW / cm ² , and photoelectric conversion efficiency = 9.5%. The thin-film solar cell module manufactured by the above process was able to obtain a higher voltage output than the module of Example 2.

Examples 4 to 6 The planar shapes of the second electrode layer and the photoelectric conversion layer of the thin-film solar cell are changed to the shapes shown in FIGS. 10 (Example 4), 11 (Example 5) and 12 (Example 6). Except that, in the same manner as in Example 1,
A thin-film solar cell module 100 was formed. The obtained thin-film solar cell module was not only excellent in translucency, but also excellent in design.

[0038]

According to the present invention, it is possible to obtain a thin-film solar cell module excellent in daylighting properties. Furthermore, since the second electrode layer and the photoelectric conversion layer of the thin-film solar cell can be patterned into a desired shape, the thin-film solar cell module of the present invention is excellent in design.

[Brief description of the drawings]

FIG. 1 is a schematic plan view of a thin-film solar cell module according to the present invention.

FIG. 2 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 1 taken along the line AA ′.

FIG. 3 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 1 taken along the line BB ′.

FIG. 4 is a schematic plan view of the thin-film solar cell module of the present invention.

5 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 4 taken along the line CC ′.

6 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 4 taken along the line DD ′.

FIG. 7 is a schematic plan view of the thin-film solar cell module of the present invention.

FIG. 8 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 7 in the EE ′ direction.

FIG. 9 is a schematic cross-sectional view of the thin-film solar cell module of FIG. 7 in the FF ′ direction.

FIG. 10 is a schematic plan view of a thin-film solar cell module according to the present invention.

FIG. 11 is a schematic plan view of a thin-film solar cell module according to the present invention.

FIG. 12 is a schematic plan view of the thin-film solar cell module of the present invention.

FIG. 13 is a schematic plan view of a conventional thin-film solar cell module.

FIG. 14 is GG ′ of the thin-film solar cell module of FIG.
It is a schematic sectional drawing of a direction.

[Explanation of symbols]

1,6 Tempered glass 2,4,7,9 EVA resin 3,8 Glass substrate 5,10 Back sealing material 11,12,13,41,42,43,71,72,7
3, 74, 75, 76, 101, 102, 103 First
Electrode layers 21, 22, 23, 51, 52, 53, 81, 82, 8
3, 84, 85, 86, 111, 112, 113 Photoelectric conversion layers 31, 32, 33, 61, 62, 63, 91, 92, 9
3, 94, 95, 96, 121, 122, 123 Second
Electrode layer 100 Thin-film solar cell 201, 202, 203, 211, 212, 213, 2
21, 222, 223 division unit

Claims (5)

[Claims] 1. A plurality of solar cells in which a transparent first electrode layer, a photoelectric conversion layer, and a second electrode layer are stacked in this order on a substrate, and a back surface sealing on the second electrode layer side. The solar cell module is covered with a material, and the maximum area of the plane with the photoelectric conversion layer and the second electrode layer is 90 to 30% of the surface area of the substrate.
Wherein the back surface sealing material is made of a translucent material. 2. The solar cell module includes a plurality of groups each including a plurality of thin-film solar cells, and the thin-film solar cells in the group are connected to each other in series.
Module. 3. The module according to claim 2, wherein the group is connected to another adjacent group in series or in parallel by a transparent electrode. 4. The module according to claim 1, wherein the photoelectric conversion layer comprises one layer or a plurality of layers. 5. The module according to claim 1, wherein the photoelectric conversion layer contains amorphous silicon as a main component.