JP2005136242A - Solar battery module and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a solar battery module with small remaining strain and its manufacturing method, in which a solar battery module board can be used efficiently. <P>SOLUTION: At least a light receive side transparent protective film 1, a light receive side transparent adhesive film 2, a solar battery cell 3 made up of a flexible board and a photoelectric conversion element formed on the flexible board, a rear face adhesive film 4, and a rear face protective film 5, are sequentially laminated, and each reinforcement member 7 is provided on both sides or on the surrounding part of the solar battery cell in the solar battery module. The reinforcement member is made of the same material as the solar battery cell board. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a flexible solar cell module.

It is composed of a light-receiving side light-transmitting protective film, a light-receiving side light-transmitting adhesive film, a solar battery cell, a back surface side adhesive film, and a back surface protective film, and a flexible member in which reinforcing members are arranged on both sides or around the solar battery cell. A solar cell module is described in Patent Document 1, for example.
1A and 1B show an example of a flexible solar cell module, where FIG. 1A is a plan view and FIG. 1B is a sectional view taken along line XX in FIG. These solar cell modules are composed of a light-receiving side translucent protective film 1 made of ETFE (ethylene terephthalate) having a thickness of 50 μm and subjected to corona discharge treatment on at least one side from the light receiving side, and EVA (ethylene vinyl acetate) having a thickness of 0.4 to 0.8 mm. A light-receiving side translucent adhesive film 2, a SUS (stainless steel) substrate coated with a thickness of 15 to 35 μm on the light-receiving surface side, and a solar cell 3 composed of an a-Si photoelectric conversion element formed thereon, 0.4 Back side adhesive film 4 made of EVA in sheet-like 0.8 mm, back surface protective film 5 made of an iron plate comprising an aluminum-zinc alloy for corrosion prevention on the surface, wiring 6 connecting between solar cells 3, solar battery The reinforcing member 7 and the terminal box 8 are arranged on the side surface of the cell 3. The solar battery cell 3 and the back surface protective film 5 may be made of plastic. These solar cell modules are stacked in the order described above, then heated and pressed at a temperature of about 120 ° C. to 160 ° C. and bonded and fixed using a vacuum laminator, and then in a dryer at 130 ° C. to 160 ° C. EVA is heat cured. Next, a terminal box for taking out the electrical output is attached.

These solar cell module configurations and manufacturing methods have the following problems.
Lamination takes time because a vacuum laminator is used.
In order to apply the roll method, prevention of soiling of the roll surface and adhesion to the roll by EVA.
Prevention of film stretching after roll forming until cooling and winding.
In particular, in the case of a solar battery cell cut to a predetermined size, the elongation between the cells becomes remarkable.
In the case of using EVA, some solar cells have a problem in that characteristics such as ITO, metal electrodes, ZnO, etc., are deteriorated due to acetic acid generated by hydrolysis of EVA, and the characteristics are deteriorated. .
JP 2000-138389 A (page 3-4, FIGS. 1, 2)

When a solar cell module is manufactured by heating and pressurizing the solar cell module according to the roll method, curing with a heating device, and winding the solar cell module, the tension required for winding is required. This portion is a portion where the solar cell module is not mechanically weakened without being reinforced by the substrate of the solar battery cell, and may be stretched and deformed. As a countermeasure, the strength of the solar cell module has been increased by arranging a replenishing member made of a thin metal plate or glass woven fabric on the side surface of the solar cell module.
However, this method is effective when using a vacuum laminator, but it is a method of applying a roll method, pressurizing and heating with a heating roll, and gradually heating and curing while applying a slight tensile force in a heating furnace. Then, there are the following problems.
When the reinforcing member is a glass fiber woven fabric, it is not possible to sufficiently replace the air and sealing resin in the glass fiber woven fabric simply by overheating and pressurizing with a heating roll, and a sufficient reinforcing effect cannot be obtained. In addition, there was a problem that air in the woven fabric expanded during outdoor use, and swelling occurred.

In addition, when a metal is used as the reinforcing member, residual stress remains in the reinforcing metal in the solar cell module due to shrinkage due to hardening of the sealing resin and expansion deformation of the solar cell module due to the tensile force, making it easy to shrink. .
After cooling, there was a problem that the solar cell module was deformed when the solar cell module was cut to a predetermined size.
This cause is presumed to be due to the difference in creep properties between the solar cell element and the reinforcing metal from the plastic substrate.
The plastic substrate also has the same force as that of the reinforcing metal, but it is affected by the heating to cure the sealing resin and the effects of peracid decomposition residues such as butanol generated when curing the sealing resin EVA. Residual strain is alleviated.

  An object of the present invention is to provide a solar cell module and a method for manufacturing the solar cell module that can solve the above-described problems and can effectively use a solar cell module substrate with little residual strain.

In order to achieve the object of the present invention, at least a light-receiving side light-transmitting protective film, a light-receiving side light-transmitting adhesive film, a solar cell comprising a flexible substrate and a photoelectric conversion element formed thereon, a back surface-side adhesive In the flexible solar cell module in which the agent film and the back surface protective film are laminated in this order, and the reinforcing member is arranged on both sides or the periphery of the solar cell, the reinforcing member is made of the same material as the solar cell substrate.
At least a light-receiving side light-transmitting protective film, a light-receiving side light-transmitting adhesive film, a solar battery cell composed of a flexible substrate and a photoelectric conversion element formed thereon, a back surface side adhesive film, and a back surface protective film are laminated. In the method of manufacturing a solar cell module including a step, the step is to send and pressurize each film between heated rolls that rotate.

  Light-receiving side translucent protective film, light-receiving side translucent adhesive film, solar cell composed of flexible substrate and photoelectric conversion element formed on it, back side adhesive film and back side protective film are laminated in this order. In the flexible solar cell module in which reinforcing members are arranged on both sides or around the solar cell, the reinforcing member is made of the same material as the solar cell substrate, so that the thermal expansion of the solar cell and the reinforcing material is caused. This is the same, so that uneven thermal expansion does not occur in the solar cell module, so that wrinkles do not occur at the time of manufacturing the solar cell module, and it is less susceptible to environmental temperature changes during use, and reliability is improved.

The configuration of the solar cell module according to the present invention is the same as that shown in FIG. 1 shown in the prior art, but a solar cell substrate is used as a band-shaped reinforcing member 7 for the purpose of preventing elongation between the solar cells due to conveyance tension. The same material is used.
The configuration of the solar cell module according to the present invention will be described in accordance with the manufacturing process using specific examples of the present invention.
1. Configuration of Solar Cell Module The solar cell module shown in FIG. 1 has a 36 μm-thick corona-treated ETFE film as the light-receiving side translucent protective film 1, and 0. 4 mm thick sheet-shaped EVA, solar cell of plastic substrate as solar cell 3 (described below), 0.4 mm thick sheet-shaped EVA as back side adhesive film 4, black as back surface protective film 5 An ETFE sheet having a thickness of 36 μm colored in the above was used.
2. Manufacture of solar battery cell For example, an a-Si solar battery cell using a substrate made of plastic made of Kapton is used. First, solar cells are arranged on a long substrate, which is narrower than the width of the substrate and in which several hundred photoelectric conversion elements are formed in an appropriate length range arranged in a row every 10 to several tens of millimeters. is there.

After the photoelectric conversion element was formed, first, both sides were cut off from the long substrate by an appropriate width (several tens of mm), and then cut into individual solar cells. The cut substrate side portion was wound around a roll and used as a reinforcing member.
As the reinforcing member, there is no problem even if a band having the same material and thickness as the substrate is separately prepared.
3. Attaching the lead wire extraction electrode to the cell.
The lead wire extraction electrode is electrically connected using an aluminum tape with a conductive adhesive material, nickel with a conductive adhesive material, a copper foil tape with a conductive adhesive material, or solder.
4. Lamination of Solar Cell Module FIG. 2 is a cross-sectional view of the main part of a roll type solar cell module manufacturing apparatus. The solar cell module manufacturing apparatus laminates individual solar cells 3 on the light-receiving side translucent protective film 1 and the light-receiving surface side translucent adhesive film 2 sent from a sheet supply device (not shown), and laminates them. In order to accomplish this, primary lamination is performed on the heating table T with the heating roll R1, and the back side protective film 1, the back side adhesive film 2 and the protective member 7 are fed in, and the secondary lamination is performed by sandwiching between the heating rolls R2 and R3. .
5. Adhesive strength of solar cell module A solar cell module is sandwiched between a steel plate and silicone rubber with a thickness of 3mm and a hardness of 50 and heated in a 100 ° C heating furnace for 1 hour. At this time, it is considered that the silane compound in the adhesive is hydrolyzed by the trace amount of moisture adsorbed on the surface of the constituent material of the solar battery cell, reacts with the surface of the adhesive metal, and the adhesion is improved.

As the light-receiving side translucent protective film, a known fluorine-based protective film (ETFE, FEP), a film obtained by vapor-depositing SiO ₂ or the like on one side of a fluorine-based protective film, a polyethylene terephthalate (PET) resin film, a clear containing an ultraviolet absorber A PET film or the like having a paint applied on the surface can be used.
As the light-receiving side light-transmitting adhesive, sheet-like EVA (peroxide crosslinking type and thermoplastic type), ethylene-methacrylic acid copolymer (EMM), ethylene-methacrylic acid ester copolymer, vinyl methoxysilane graft Polyethylene, silicone resin, acrylic resin, polyester resin and the like can be used.
As the back side adhesive, sheet-like EVA (peroxide crosslinking type and thermoplastic type), ethylene-methacrylic acid copolymer (EMM), ethylene-methacrylic acid ester copolymer, vinyl methoxysilane grafted polyethylene, A silicone resin, an acrylic resin, a polyester resin, and a sheet obtained by blending a pigment such as carbon into each resin in the previous period can be used.

For the configuration of the lead wire extraction electrode, a metal plate made of copper foil and a solder plate or tin or an alloy of tin and silver plated, dipped, sprayed, or the like can be used. The thickness of solder plating, tin plating or the like is preferably 1 μm or more and 5 μm or less.
If it is 1 μm or less, there is no effect in preventing copper oxidation, and if it is 5 μm or more, there is a problem that the manufacturing time becomes long.
The thickness of the metal plate is preferably 0.1 mm or less, more preferably 0.05 mm or less.
As the insulating film, the heat resistant temperature is preferably 150 ° C. or higher. The reason is to prevent deformation during soldering. Examples of the film having a high heat resistant temperature include a polyimide film, an aramid resin film, a polyethylene naphthalate film, and a liquid crystal polyester resin film.

The thickness of the insulating film is preferably 50 μm or less, more preferably 25 μm or less.
Further, the thickness of the adhesive layer is preferably 50 μm or less. More preferably, it is 30 μm or less.
The reason for this is that if the thickness of the entire lead wire extraction electrode is increased, the solar battery cell may be deformed when electrically connected to the solar battery cell, and stress may be applied to the connection portion. Because there is.
As the back side protective film, ETFE, FEP, PET, PEN, polypropylene resin, cycloaliphatic-polyethylene copolymer, polycyclopentene resin (TPX), polycarbonate, acrylic resin sheet, and at least one side of these sheets is made of SiO _x , or a sheet of each of the above-mentioned resins on which a mixture of SiO _x and Al _x O _x is vapor-deposited, and a sheet in which a resin film sheet is bonded to both sides or one side of aluminum foil, iron foil, etc. with an adhesive. Can do.
Example 1
The long solar cell is 480mm wide, 260m long and 50μm thick on a Kapton substrate. The area where 200 photoelectric conversion elements are formed in a range of 400mm wide and 800mm long is arranged in a row every 10mm. It is a thing.

First, both sides were cut 38 mm wide from the long substrate, and then cut to 805 mm length to obtain individual solar cells. The cut substrate side portion was wound around a roll and used as a reinforcing member.
The solar cells cut by the solar cell module manufacturing apparatus were supplied to the laminating apparatus (FIG. 2) at predetermined intervals. The reinforcing member 7 was arrange | positioned on the both sides, and the solar cell module was produced according to said process. The setting conditions of each part at this time are as follows.
Cell heating roll temperature 130 ° C, pressure 10kg.
Laminating roll temperature 150 ° C, pressure 100kg.
Sheet conveyance speed 1m / min.
Comparative Example 1
EVA (heat crosslinking type) was used in place of the adhesive material and structure 1 in the examples. Similarly, it was produced in the same manner as in the Example except that the temperature of the heating furnace in Step 5 was changed to 150 ° C. after the production with the solar cell module production apparatus.

Table 1 shows the results of evaluating the reliability of the solar cell modules of the examples and comparative examples in a high temperature storage test, a heat cycle test, and a weather test.
Heat cycle test: −40 ° C to 90 ° C (3-hour cycle), number of times required for conversion efficiency (Eff) to change by 5% △ Eff = 1- (Eff after weathering test 1000h / Eff after stabilization treatment)
High-temperature and high-humidity storage test: The conversion efficiency is measured every 300h by leaving the solar cell module in 85 ℃ and 95% RH.
Xenon lamp weather test machine: 1SUN light intensity, solar cell module temperature 70 ℃, relative humidity 60%.
Each test sample was light-stabilized for 500 hours in advance.

  From this result, it can be seen that the solar cell module of the present invention has a life of more than twice as long as the high temperature and high humidity leaving test compared to the comparative example.

An example of a flexible solar cell module is shown, (a) is a top view, (b) is XX sectional drawing in (a). It is sectional drawing of the principal part of a roll type solar cell module manufacturing apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Light reception side translucent protective film 2 Light reception side translucent adhesive film 3 Solar cell 4 Back surface side adhesive film 5 Back surface protective film 6 Wiring 7 Reinforcement member 8 Terminal part R1, R2, R3 Heating roll T Heating table

Claims (2)

At least a light-receiving side light-transmitting protective film, a light-receiving side light-transmitting adhesive film, a solar cell composed of a flexible substrate and a photoelectric conversion element formed thereon, a back surface side adhesive film, and a back surface protective film are laminated in this order. A flexible solar cell module in which reinforcing members are arranged on both sides or around the solar cell, wherein the reinforcing member is made of the same material as the solar cell substrate. At least a light-receiving side light-transmitting protective film, a light-receiving side light-transmitting adhesive film, a solar cell composed of a flexible substrate and a photoelectric conversion element formed thereon, a back surface side adhesive film, and a back surface protective film are laminated. The method for manufacturing a solar cell module according to claim 1, wherein the step includes sending and pressurizing each film between heated rolls that rotate.

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