JPH02155277A - Solar cell module - Google Patents

Abstract

PURPOSE:To prevent power loss at the time of output and peeling of leads from a solar cell module body by partly removing the transparent electrode of a load connecting part externally of the solar cell module. CONSTITUTION:In a part in which conductive adhesives 5a, 5b are connected to a transparent electrode 2, part of the transparent electrode 2 is removed. This removal is conducted by etching, laser scribing, scratching, etc. An interval to be removed depends upon an area of the conductive adhesives 5a, 5b in contact with the transparent electrode 2, and is generally desired 20-70% of the width in contact. For example, parts 7a, 7b of a tin oxide layer 2 are removed, and then leads 6a, 6b are attached by silver pastes 5a, 5b. Thus, contact resistance of external leads to a solar cell module body is reduced, power loss can be reduced, and peeling of external leads can be effectively prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solar cell module. More specifically, it is an amorphous semiconductor solar cell module in which multiple solar cells are integrated on a transparent substrate such as glass, and the connection structure of the lead wires for taking out the output to the outside has been improved. The present invention relates to a solar cell module that can prevent an increase in resistance and peeling of lead wire connection parts.

[Conventional technology]

An example of a conventional integrated solar cell module structure is shown in FIGS. 2 and 3. In Figures 2 and 3, transparent substrate (1)
The upper transparent electrode (2), the amorphous semiconductor layer (3), and the back electrode (4) are each separated, and a plurality of solar cells are formed on the transparent substrate (1).

The transparent electrode (2) is made of ITO, 5n02, etc.
Transparent substrate (1) by B vapor deposition, sputtering, thermal CVD, etc.
formed on top. The amorphous semiconductor layer (3) is formed by glow-discharging silane gas or the like, and has at least one pn junction. As the back electrode (4), a single film of metal such as N or a multilayer film such as metal silicide/M is used to improve heat resistance.

The transparent electrode ('2J) is separated from the amorphous semiconductor layer (3) and the back electrode (4) after forming each layer on the entire surface.
This is done by removing a portion of each layer by laser scribing, pattern etching, or the like.

The output of the solar cell module main body obtained in this way can be taken out to the outside through lead wires (6a) and (6b). Multiple solar cell modules are often connected to form a larger module; in this case, the lead wires (6a) and (6b) are each connected to an adjacent solar cell module body. Lead wire (6a), (
6b) are connected to the solar cell module main body by conductive adhesives (5a) and (5b) such as solder and silver paste, respectively. The conductive adhesive (5a) is the transparent electrode (2)
Also, the conductive adhesive (5b) is connected to the back electrode (4) or the transparent electrode (2).

[Problem to be solved by the invention]

However, until the lead wires (6a) and (6b) are connected to the predetermined electrodes using conductive adhesives (5a) and (5b), the solar cell module undergoes various processes such as laser Φ scribing and pattern etching. , dirt such as oil may adhere to the surface of the solar cell module. Further, in most cases, a thin amorphous semiconductor layer is formed on the transparent electrode (2) at the portion to which the conductive adhesive (5a) is connected, even if a mask is used during glow discharge. If the conventional connection method shown in Fig. 2 or 3 is adopted in such a case, the contact resistance will increase due to the oil contamination and the thinly attached amorphous semiconductor layer, making it difficult to take out the output. At the same time as power loss occurs, lead wires (6a) and (6b) are exposed to conductive adhesive (5a) and (5b).
), there was also the inconvenience of peeling off from the solar cell module body.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a solar cell module that eliminates the drawbacks of the conventional example. That is, an object of the present invention is to provide a solar cell module that can prevent power loss during output extraction and separation of lead wires from the module body.

[Means to solve the problem]

The solar cell module of the present invention has several solar cells formed by sequentially laminating a transparent electrode, an amorphous semiconductor film, and a back electrode from the light-receiving surface side on a transparent substrate, and the transparent electrode and metal A solar cell module in which the plurality of solar cells are connected in series or in series-parallel using electrodes, the transparent electrode being partially removed from the lead wire connection portion to the outside of the solar cell module. It is characterized by

〔Example〕

Hereinafter, the solar cell module of the present invention will be explained based on the drawings.

FIG. 1 is an explanatory cross-sectional view of one embodiment of the solar cell module of the present invention.

In FIG. 1, (1) is a transparent substrate having an insulating surface such as soda lime glass or soda lime glass coated with 8102, and on the transparent substrate (1) is a transparent electrode made of ITO, 5n02, etc. (The thickness of the transparent electrode ('2J) is not particularly limited in the present invention, but is approximately too.

~10,000 people, E8 evaporation, sputtering, thermal CV
D and the like on the transparent substrate (1).

An amorphous semiconductor layer (3) is formed on the transparent 1u pole (2) by glow discharge, plasma CVD, or the like.

The amorphous semiconductor constituting the amorphous semiconductor layer (3) used in the present invention is not particularly limited as long as it is an amorphous semiconductor or an amorphous semiconductor containing crystal. Specific examples of such semiconductors include a-81:II%a-8IC:tl
, a-3l:F:HSa-8IGe:II.

a-8ISn:It, a-8IN:If, a-8IG
e:P:It, a-8ISn:P:It.

Examples include μc-3l:II.

The amorphous semiconductor layer (3) is configured to generate a photovoltaic force by forming the amorphous semiconductor into a PIN junction, for example. In addition to the above-mentioned PIN junction, various junctions such as a PN junction, a multiple junction such as PINPIN, and a Peter junction are used for the junction.

The thickness of the amorphous semiconductor layer (3) is approximately 2000 to 15.0
There are 00 people.

A back electrode (4) is formed on the amorphous semiconductor layer (3) by vapor deposition, sputtering, or the like. The back electrode (4) used in the present invention is USAg, Au.

808-NL % Cu 1Cr, Zn, TI, etc., preferably with a reflectance of 20 to 20 for light with a wavelength of 0.6ρ or more
99%, more preferably as high as 45 to 99%, and the electrical type conductivity is 0.1 xtos to 8.2 xtos (Ω
-cII)-' and electrodes formed from large metals, but are not limited thereto. Further, the back electrode (4) may be a single layer or a multilayer.

To separate the transparent electrode (2), amorphous semiconductor layer (3), and back electrode (4), each layer is formed on the entire surface, and then a portion of each layer is removed by laser scribing, pattern etching, etc. It is done by doing.

The solar cell module of the present invention is characterized by a conductive adhesive (
5a) and (5b) are connected to the transparent electrode (2), a portion of the transparent electrode (2) is removed.The problem of increased contact resistance and peeling is due to the above-mentioned problem of dirt adhesion. It is effective to remove a portion of the transparent electrode (2) immediately before attaching the lead wires (6a) and (6b) to the module body.

This removal may be performed by etching, laser scribing, scratching, or the like. The distance (N) to be removed varies depending on the area where the conductive adhesives (5a) and (5b) contact the transparent electrode (2), but is approximately 20 mm of the width where they contact each other.
~70% is preferred. When separating the transparent electrode (2), a portion of the portion connected to the conductive adhesive (5a), (5b) may be removed at the same time by laser scribing, pattern etching, etc. In this case, the effect of the present invention is weakened by the influence of dirt and the thinly attached amorphous semiconductor layer.

Example A tin oxide layer (2) was formed on a glass substrate (1) with a thickness of 6,000 yen by laser scribing.
was separated. Thereafter, a portion corresponding to (5a) was masked to form an amorphous silicon layer (3). The amorphous silicon layer (3) has a p
It consists of amorphous silicon carbide, i-type amorphous silicon, and n-type microcrystalline silicon.
It had two pn junctions. Thereafter, the amorphous silicon layer (3) was separated by laser scribing.

Furthermore, after forming N on the entire surface of the amorphous silicon layer (3), pattern etching was performed to remove unnecessary portions, thereby forming an M electrode (4).

After that, parts (7a) and (7b) of the tin oxide layer ('2J) are removed by irradiation with laser light, and then the lead wires (6a) and (eb) are bonded to the silver paste (5a), respectively.
, (5b).

The solar cell module obtained in this way has less power loss at the lead wire take-out part, and has a lower fill-in ratio than the solar cell module with the conventional structure shown in FIGS. 2 and 3.
The factor was about 6 to 1096 high. Furthermore, as a result of the peeling test of the silver pastes (5a) and (5b), there was a difference in the adhesion strength between the silver pastes (5a) and (5b) and the solar cell module body, and the structure of the present invention was significantly superior. It was found that it was difficult to peel off. Note that - of the tin oxide layer (2)
As methods for removing portions (7a) and (7b), in addition to laser scribing, we tried scraping with a knife or using an ultrasonic cutter, but the results were similar.

〔Effect of the invention〕

As is clear from the above description, in the solar cell module of the present invention, a part of the transparent electrode at the connection part of the lead wire to the outside is removed, and the contact resistance between the lead wire to the outside and the main body of the solar cell module is reduced. It is possible to reduce the size of the lead wire, reduce power loss, and reliably prevent the lead wire from peeling off to the outside.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of a solar cell module of the present invention, and FIGS. 2 and 3 are explanatory cross-sectional views of a conventional solar cell module. (Symbols in drawings) (1): Transparent substrate (2); Transparent electrode (3): Amorphous semiconductor layer (4): Back electrode (5a), (5b): Conductive adhesive (6a), (Gb ): Lead wires (7a), (7b): Removal section Patent applicant: Kanekabuchi Chemical Industry Co., Ltd.

Claims (1)

[Claims] 1 A plurality of solar cells formed by sequentially stacking a transparent electrode, an amorphous semiconductor film, and a back electrode from the light-receiving surface side are arranged on a transparent substrate, and the plurality of solar cells are formed using the transparent electrode and the metal electrode. A solar cell module comprising solar cells connected in series or series-parallel, characterized in that a transparent electrode at a lead wire connection portion to the outside of the solar cell module is partially removed. .