JP2000243996A - Solar-cell module and manufacture thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar-cell module which exhibits a high reliability and improves the throughput of a manufacturing process. SOLUTION: To collect an electrical output, holes are formed in a lowermost surface member (insulating film) 105 and a lower surface sealing material (sealing material resin) 104 in such a manner that each hole reaches an electrode 107 which is provided on the back of a photovoltaic element 101. These holes are formed by providing openings 106a and 106b in such a manner that the member 105 communicates with the material 104 prior to a step of laminating the member 105 and the material 104 onto the element 101. The opening 106b formed in the member 105 is made larger than the opening 106a formed in the material 104.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a solar cell module and a method of manufacturing the same, and more particularly, to a solar cell module having an opening for taking out an electric output on a non-light receiving side and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventional solar cell modules are roughly classified into those which cover the outermost surface on the light receiving surface side with glass and those which cover the outermost surface with a light transmitting film. To further classify, the "substrate method" in which the glass and the photovoltaic element are bonded with a sealing resin to the solar cell module covered with glass
And a "super straight type" solar cell module in which a photovoltaic element is formed directly on a glass substrate. In a solar cell module covered with a translucent film, a method of bonding the translucent film and the photovoltaic element with a sealing resin is generally adopted.

On the other hand, these solar cell modules have a common configuration on the non-light-receiving surface side. That is, in the conventional solar cell module, the insulating film is bonded to the photovoltaic element via the sealing resin. In particular, when the insulating film is directly exposed outdoors, a fluororesin film is preferably used in consideration of weather resistance. Further, when the front surface is covered with a light-transmitting film, simply covering both the front and back surfaces with the film is insufficient in rigidity. Therefore, a reinforcing plate is sometimes attached to the outside of the insulating film.

[0004] By the way, the electric output of such a solar cell module is generally taken out from the back side or side face of the module, and the method of taking out from the back side is mainly used. The specific method of extracting the electric output is as follows.

First, a plurality of photovoltaic elements are connected in series or in parallel according to a desired voltage or current to form a photovoltaic element group, and then the positive electrode of the photovoltaic element group is connected to the negative electrode. An extreme electrode is provided on the back side of the photovoltaic element group. This group of photovoltaic elements is laminated using a covering material. At this stage, the back surface of the photovoltaic element group is covered with a sealing resin and an insulating film. Then, the electrode portion is exposed by removing the sealing material resin and the insulating film covering the electrode portion, and an electrical output can be taken out by connecting a conductor to the exposed portion with solder or the like. In addition, in consideration of the reliability of the output extraction unit, a terminal box is often provided at a site where the electric output is extracted.

[0006]

However, in the above-described conventional solar cell module, the sealing material resin and the insulating film are removed after the photovoltaic element group is laminated, so that the sealing material is provided on the electrode portion. Resin may remain, which hinders subsequent soldering of the conductor.

[0007] Therefore, the soldering strength of the terminal portion is weakened, which has been one of the causes of lowering the reliability of the solar cell module. Moreover, in order to remove the sealing material resin and the insulating film, a method of piercing the sealing material resin and the insulating film to be removed with a cutter knife or the like is used.
It was difficult to penetrate the sealing resin and the insulating film without damaging the electrode portion. Further, the sealing material resin and the insulating film are peeled off from the cutter cut end face, which is another factor that lowers the reliability of the solar cell module.

Further, since it takes time to remove the sealing resin and the insulating film, it has been an obstacle to improving the throughput in manufacturing solar cell modules.

Accordingly, an object of the present invention is to provide a solar cell module having high reliability and capable of improving the throughput in the manufacturing process, and a method for manufacturing the same.

[0010]

As a result of intensive research and development to solve the above-mentioned problems, the present inventor has found that it is best to use the following means.

That is, in the solar cell module according to the present invention, there is provided a photovoltaic element comprising at least a transparent outermost member covering a light receiving image side of the photovoltaic element and a transparent surface sealing material; In the solar cell module having at least the outermost member covering the non-light-receiving image side and a back surface covering material made of a back surface sealing material, the back surface covering material is provided before the step of laminating the photovoltaic element. Further, an opening communicating with an electrode disposed on the back surface of the photovoltaic element for taking out an electric output, and the opening provided on the backmost member is provided on the back surface other than the backmost member. It is characterized by being larger than the opening provided in the covering material.

It is preferable that the rearmost member is selected from one of a polymer resin film, a polymer resin plate, and a metal plate.

The inside of the opening has a melting point or softening point higher than the maximum temperature reached by the back surface coating during the laminating step, and has a thickness substantially equal to the thickness of the entire back surface coating material. Preferably, a plug member is provided.

Preferably, the plug member is made of an elastic material.

It is preferable that the elastic body is made of silicone rubber or fluorine rubber.

The method for manufacturing a solar cell module according to the present invention is for manufacturing each solar cell module having the above-mentioned features. The photovoltaic element is provided on the back surface covering material for extracting electric power. Providing an opening communicating with the electrode disposed on the back surface, wherein an opening provided in the backmost member is larger than an opening provided in the back surface covering material other than the backmost member; The method includes a step of laminating a power element.

According to the present invention, before the step of laminating the back surface covering material to the photovoltaic element, an opening is provided in advance so as to allow the outermost back surface member and the back surface sealing material to communicate with each other. And an opening provided on the backmost member is larger than an opening provided on the backside sealing material. Therefore, since the residue of the sealing material resin does not adhere to the electrode, a problem does not occur in soldering to the electrode due to the residue of the sealing material resin, and a high-quality solar cell module can be provided.

Further, since the holes communicating with the electrodes are formed before the laminating step, there is no need to pierce the back surface coating material using a jig such as a cutter knife after lamination. For this reason, there is no risk of damaging the electrode by a cutter knife or the like, and the quality of the solar cell can be further improved.

Further, since it is not necessary to form holes after lamination, the number of steps is reduced, and the throughput of solar cell module production can be improved.

Further, since the opening provided in the backmost member is larger than the opening provided in the back covering material other than the backmost member located inside the backmost member,
The sealing material resin enters between the opening of the backmost member and the opening of the backing material other than the backmost member. That is, the end of the opening of the rearmost member is covered with the sealing resin, the adhesion between the rearmost member and the backing material other than the rearmost member is improved, and it is difficult for the rearmost member to be peeled off from the opening end. The reliability of the terminal extraction portion for extracting the terminal can be improved.

Further, according to the present invention, the rearmost member is formed by using one of a polymer resin film, a polymer resin plate and a metal plate. Therefore, the mechanical strength of the solar cell module can be increased, and distortion and warpage due to a temperature change can be prevented.

Further, according to the present invention, inside the opening,
A plug member having a melting point or softening point higher than the maximum temperature reached by the back cover material during the laminating step and having a thickness substantially equal to the thickness of the entire back cover material is provided. Therefore, a hole can be easily formed by removing the plug member after bonding the solar cell module laminate.

According to the present invention, the material of the plug member is
It has a higher melting or softening point than the maximum temperature reached by the backing material during the laminating process. Therefore, the plug member is not deformed by melting or softening during the laminating process.

Further, by making the thickness of the plug member substantially the same as the thickness of the entire back cover material, the plug member is not pressed against the electrode or the photovoltaic element during the laminating step, and the electrode or the photovoltaic element is prevented from being pressed. Can be prevented from being deformed.

Further, according to the present invention, the plug member is formed of an elastic body. Therefore, even if the plug member is pressed against the electrode or the photovoltaic element during the laminating step, it is possible to prevent the deformation of the electrode or the photovoltaic element.

According to the present invention, the elastic body is made of silicone rubber or fluorine rubber. Therefore, the releasability between the plug member and the sealing material resin can be improved.

[0027]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a solar cell module according to the present invention will be described with reference to the drawings.

FIG. 1 is a schematic sectional view showing one embodiment of a solar cell module according to the present invention.

In FIG. 1, reference numeral 100 denotes a solar cell module laminate, 101 denotes a photovoltaic element group, 102 denotes a sealing material resin on the light receiving image side, 103 denotes a light transmitting member on the light receiving surface side, 104
Is a back surface side sealing material resin, 105 is a back side green insulating film, 106a is an opening provided in the back side sealing material resin 104, 106b is an opening provided in the insulating film 105,
Reference numeral 107 denotes an electrode for extracting an electric output.

The light transmitting member 103 on the light receiving surface side corresponds to the outermost surface member of the present invention, and the sealing material resin 102 on the light receiving surface side is used.
Corresponds to the surface sealing material of the present invention, and the insulating film 105
Corresponds to the rearmost member of the present invention, and the sealing material resin 1 on the rear surface side
04 corresponds to the back surface sealing material of the present invention, that is, the back surface covering material other than the rearmost member.

In order to manufacture the solar cell module according to the present invention, as shown in FIG. 1, a photovoltaic element group 101 is formed by sealing a resin 102 on a light receiving surface side and a light transmitting member 10 on a light receiving surface side.
3. In order to laminate using the insulating film 105 on the back side, the translucent member 103 / sealing material resin 1
02 / photovoltaic element group 101 / sealing material resin 104 / insulating film 105 in this order to form a solar cell module laminate 100.

Further, at a position corresponding to the electrode 107 for extracting electric output, which is disposed on the back surface of the photovoltaic element group 101,
Openings 106a and 106b are provided so that the sealing resin 104 on the back side and the insulating film 105 communicate with each other. Here, the opening 106b of the insulating film 105
Is made larger than the opening 106a of the sealing resin 104 on the back side. After the members are superposed in this way, the solar cell module laminate 100 is bonded by a vacuum lamination method, which is a conventionally known method, to manufacture a solar cell module.

FIG. 2 is a schematic sectional view showing another embodiment of the solar cell module according to the present invention.
Is a schematic cross-sectional view before a laminating step, and FIG. 2B is a schematic configuration diagram after laminating.

In FIG. 2, reference numeral 200 denotes a solar cell module stack, 201 denotes a photovoltaic element group, 202 denotes a light-receiving-side sealing material resin, 203 denotes a light-receiving surface-side translucent member,
Is an encapsulation resin on the back side, 205 is a green film on the back side, 206a is an opening provided on the encapsulation resin 204 on the back side, 206b is an opening provided on the insulating film 205,
207 is a plug member, 208 is a hole for taking out an electric output, 209
Denotes electrodes for extracting electric output.

The light transmitting member 203 on the light receiving surface side corresponds to the outermost surface member of the present invention, and the sealing material resin 202 on the light receiving surface side is used.
Corresponds to the surface sealing material of the present invention, and the insulating film 205
Corresponds to the rearmost member of the present invention, and the sealing material resin 2 on the rear surface side
04 corresponds to the back surface sealing material of the present invention, that is, the back surface covering material other than the rearmost member.

In the embodiment shown in FIG. 2, a plug member 207 is provided inside each of the openings 206a and 206b provided in communication with the sealing resin 204 and the insulating film 205 on the back side.
Is arranged. And the solar cell module laminate 2
After attaching 00, the plug member 207 is removed to form a hole 208 for extracting electric output.

Note that the material of the plug member 207 used here is not to be melted or deformed during the laminating step. Preferably, 205 has a higher melting or softening point than the maximum temperature reached.

If the electrode 209 is pushed by the plug member 207 during the laminating process, the electrode 207 or the photovoltaic element group 201 may be deformed. For this reason, it is preferable that the thickness of the plug member 207 is equal to the thickness of the entire back surface sealing material resin 204 and the insulating film 205 as the back surface covering material. Also, for the same purpose, the plug member 2
More preferably, 07 is an elastic body.

As a specific material of the plug member 207, a fluororesin or silicone resin is preferable in consideration of the releasability from the sealing material resin 204 on the back side, and the most preferable material is fluororubber or silicone rubber. It is.

Further, the surface layer of the plug member 207 may be made of a fluorine resin or a silicone resin, and the inside may be made of a different material. For example, the photovoltaic element group 201
Is a ferromagnetic material, the plug member 207 can be made to adhere to the photovoltaic element group 201 by forming a magnet coated with a fluororesin as the plug member 207, and the plug member 207 is opened. It can be prevented from dropping from the 206b.

Next, a photovoltaic element preferably used in the present invention, a sealing material resin on the light receiving image side, a light transmitting member on the light receiving surface side,
The sealing resin and the insulating film on the back side will be described.

[Photovoltaic element] As the photovoltaic element,
Conventionally known photovoltaic elements such as a crystalline silicon solar cell, a polycrystalline silicon solar cell, an amorphous silicon solar cell, a copper indium selenide solar cell, and a compound semiconductor solar cell can be selected and used depending on the purpose. These photovoltaic elements are connected in series or in parallel depending on the desired voltage or current. Alternatively, a desired voltage or current can be obtained by integrating a photovoltaic element on an insulated substrate.

<Surface Covering Material> [Surface Sealing Material Resin] The surface sealing material resin, that is, the sealing material resin on the light receiving surface side, covers the unevenness on the surface of the photovoltaic element with a resin.
This is a member necessary to protect the photovoltaic element from severe external environments such as temperature change, humidity, and impact, and to ensure adhesion between the translucent member and the photovoltaic element.

Therefore, the sealing resin on the light receiving surface side includes
Weather resistance, adhesion, filling, heat resistance, cold resistance and impact resistance are required. Examples of resins satisfying these requirements include polyolefins such as ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer (EEA), and polyvinyl butyral resin. Base resin, urethane resin, silicone resin, fluorine resin and the like.

In particular, EVA has well-balanced physical properties for use in solar cells and is preferably used. However, since EVA as it is has a low heat deformation temperature and easily deforms or exhibits creep under high-temperature use conditions, it is preferable to increase the heat resistance by crosslinking.

For EVA, it is general to crosslink with an organic peroxide. Crosslinking with an organic peroxide is performed by free radicals generated from the organic peroxide extracting hydrogen and halogen atoms in the resin to form a CC bond. Thermal decomposition, redox decomposition and ionic decomposition are known as methods for activating organic peroxides.
Of these activation methods, a thermal decomposition method is generally preferred.

The above-mentioned organic peroxide can be used in combination with a sealing material, and crosslinking and thermocompression bonding can be performed while heating under pressure under vacuum. The heating temperature and time can be determined by the thermal decomposition temperature characteristics of each organic peroxide. In general, the heating and pressurization is completed at a temperature and a time at which the thermal decomposition proceeds by 90%, more preferably 95% or more.

To confirm the crosslinking of the encapsulant resin, the gel fraction may be measured. In order to prevent deformation of the encapsulant resin at a high temperature, the crosslinking is performed so that the gel fraction becomes 70 wt% or more. Is preferred.

The material of the sealing material used in this embodiment is as follows.
It is excellent in weather resistance. For further improving the weather resistance or protecting the lower layer of the sealing material, an ultraviolet absorber may be used in combination. As an ultraviolet absorber,
Known compounds can be used. However, it is preferable to use a low-volatility ultraviolet absorber in consideration of the usage environment of the solar cell module. Specific examples of the ultraviolet absorber include various organic compounds based on salicylic acid, benzophenone, benzotriazole, and cyanoacrylate.

By adding a light stabilizer in addition to the ultraviolet absorber, a sealing material more stable to light can be obtained. Typical light stabilizers are hindered amine light stabilizers. Hindered amine light stabilizers do not absorb ultraviolet light, unlike ultraviolet light absorbers. However, when used in combination with an ultraviolet absorber, a remarkable synergistic effect is exhibited. Of course, other than the hindered amine-based compounds, there are compounds that function as light stabilizers. However, light stabilizers other than hindered amines are often colored, which is not preferable for the sealing material of the present invention.

Further, in order to improve heat resistance and heat workability,
It is also possible to add antioxidants. As the chemical structure of the antioxidant, there are monophenol type, bisphenol type, polymer type phenol type, sulfur type and phosphoric acid type.

When it is assumed that the solar cell module is used in a more severe environment, it is preferable to improve the adhesive strength between the sealing material and the photovoltaic element or the light-transmitting member on the light-receiving surface side. In order to improve the adhesion between the sealing material and the photovoltaic element or the light-transmitting member on the light receiving surface side, a silane coupling agent or an organic titanate compound may be added to the sealing material.

An EVA sheet for a solar cell obtained by molding EVA containing these additives into a sheet is commercially available. One example of the formulation is that 2,100 parts by weight of a crosslinking agent is added to 100 parts by weight of an EVA resin (vinyl acetate content: 33%).
1.5 parts by weight of dimethyl-2,5-bis (t-butylperoxy) hexane, 0.3 parts by weight of 2-hydroxy-4-n-octoxybenzophenone as an ultraviolet absorber,
0.1 parts by weight of bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate as a light stabilizer, 0.2 parts by weight of tris (mono-nonylphenyl) phosphite as an antioxidant, silane cup It contains 0.25 parts by weight of γ-methacryloxypropyltrimethoxysilane as a ring agent. The solar cell module can be easily manufactured by inserting such an EVA sheet between the photovoltaic element and the light-transmitting member on the light-receiving surface side and by heat-pressing.

[Outermost member] The outermost member, that is, the light-transmitting member on the light-receiving surface side, is located on the outermost layer of the solar cell module, and therefore needs to include transparency, weather resistance, contamination resistance, and mechanical strength. In addition, performance for ensuring long-term reliability of the solar cell module in outdoor exposure is required. Examples of the light-transmitting member on the light receiving surface side include white plate reinforced glass, a fluorine resin film, and an acrylic resin film.

The white-plate tempered glass is widely used as a light-transmitting member on the light-receiving image side of a solar cell module because it has high transparency, is strong against impact, and is hard to break.

However, recently, there are many cases where the solar cell module is required to be lightweight and flexible. In such a case, a resin film is used as the light-transmitting member on the light-receiving surface side.

Among them, fluororesin films are preferably used because of their excellent weather resistance and stain resistance. Specific examples of the fluororesin film include a polyvinylidene fluoride (PVdF) film, a polyvinyl fluoride (PVF) film, and an ethylene-tetrafluoroethylene copolymer (ETFE) film. In particular, the PVdF film is excellent in terms of weather resistance, but the ETFE film is excellent in terms of compatibility between weather resistance and mechanical strength and transparency.

<Back-Surface Coating Material> [Backmost-Surface Member] The most-rear-surface member refers to a member disposed on the most back side of the back-surface coating material, and examples thereof include an insulating film and a reinforcing plate.

The insulating film is a member necessary for maintaining electrical insulation between the back side of the photovoltaic element and the outside.
As the material of the insulating film, a material which can secure sufficient electric insulation with the conductive substrate, has excellent long-term durability, can withstand thermal expansion and thermal contraction, and has flexibility is preferable. Suitable insulating films include nylon, polyethylene terephthalate (PET), and polyvinyl fluoride (PVF).

A reinforcing plate may be attached to the outside of the insulating film in order to increase the mechanical strength of the solar cell module or to prevent distortion and warpage due to a temperature change. As the reinforcing plate, for example, a steel plate, a plastic plate, or an FRP (glass fiber reinforced plastic) plate is preferable.

[Back Surface Sealing Material Resin] The sealing material resin on the back surface is a member for bonding the photovoltaic element to the rearmost member such as an insulating film and a reinforcing plate. As the material of the sealing resin on the back side, a material which can secure sufficient adhesiveness to the photovoltaic element, has excellent long-term durability, can withstand thermal expansion and thermal contraction, and has flexibility is preferable. The material of the sealing material resin preferably used on the back side is EV
A, a thermoplastic resin such as polyvinyl butyral, a double-sided tape, and a flexible epoxy adhesive. Of course, the same material as the sealing material resin on the light receiving surface side can be used as the sealing material resin on the back surface side, and such a case is often the case. That is, the above-mentioned crosslinked EV
It is common to use A also on the back side.

[0062]

EXAMPLES Hereinafter, a method for manufacturing a solar cell module according to the present invention will be described in detail with reference to specific examples. The method of manufacturing a solar cell module according to the present invention is not limited to the following examples, and can be variously modified within the scope of the gist.

<Example 1> [Photovoltaic element] In the solar cell module of Example 1,
First, an amorphous silicon (a-Si) solar cell (photovoltaic element) was manufactured. The manufacturing procedure will be described with reference to FIG.

In order to manufacture the amorphous silicon solar cell of Example 1, first, as shown in FIG.
2 and the ZnO layer (film thickness 5
000 °) are sequentially formed.

Then, by plasma CVD, the SiH
₄ and PH ₃ and the n-type a-Si layer from a mixed gas of H _2, Si
An i-type a-Si layer is formed from a mixed gas of H ₄ and H ₂ , and a p-type microcrystalline μc-Si layer is formed from a mixed gas of SiH ₄ , BF ₃ and H _2. 4000 / p layer thickness 100 / n layer thickness 100 / i layer thickness 800 / p
A tandem a-Si photoelectric conversion semiconductor layer 503 having a layer thickness of 100 ° was formed.

Next, as the transparent conductive layer 504, In ₂ O ₃
Was formed by vapor deposition of In by a resistance heating method in an O ₂ atmosphere.

Further, a grid electrode 505 for current collection is formed by screen printing of a silver paste. Finally, a copper tab is attached to a stainless substrate using a stainless solder 508 as a negative terminal 506b, and a positive terminal 506a is formed. Then, a tin foil tape was attached to the current collecting electrode 505 with a conductive adhesive 507 to serve as an output terminal to obtain a photovoltaic element. Then, a plurality of the photovoltaic elements were connected in series to form a photovoltaic element group.

Finally, a positive electrode of the positive terminal element,
An output extraction electrode was obtained by extending the negative electrode of the negative terminal element and disposing it on the back surface of the photovoltaic element group.

[Modularization] Next, a method for manufacturing a solar cell module by covering the photovoltaic element group with a coating material will be described with reference to FIG.

As shown in FIG. 3, the photovoltaic element group 30
1, EVA sheet 302 (thickness: 460 μm, vinyl acetate content: 33 wt%, melt flow rate: 30), EVA
Sheet 303 (thickness 230 μm, vinyl acetate content 33
wt%), non-stretched ETFE with corona discharge treatment on one side
Film 304 (thickness 50 μm), polyethylene terephthalate (PET) film 305 (thickness 100 μm)
m), Galvalume steel plate 306 (0.4 mm thick)
ETFE film 304 / EVA sheet 3 from the light receiving surface side
02 / Photovoltaic element group 301 / EVA sheet 303 / P
ET film 305 / EVA sheet 303 / steel plate 306
In this order to form a solar cell module laminate 300.

The ETFE film 304 on the light receiving surface side
Corresponds to the outermost member of the present invention, the EVA sheet 302 on the light receiving surface side corresponds to the surface sealing material of the present invention, the steel plate 306 corresponds to the outermost member of the present invention, and the EVA sheet 3 on the back surface side.
The 03 / PET film 305 / EVA sheet 303 corresponds to a back surface coating material other than the outermost surface member of the present invention.

When the solar cell module laminate 300 is formed, the electrodes 308 for taking out the output of the photovoltaic element group 301 are formed.
Sheet EVA sheet 303 / PET film 305 / EV
A hole having a diameter of 6 mm is formed in the A sheet 303, and a silicone rubber stopper member 30 having a diameter of 6 mm and a thickness of 1 mm is formed inside the hole.
7 was placed. Also, the steel plate 306 which is the rearmost member,
A hole having a diameter of 15 mm was formed concentrically with the above hole.

The solar cell module laminate 300 thus formed was heated and pressed at 150 ° C. for 30 minutes while being evacuated using a vacuum laminating apparatus. Thereafter, by removing the plug member 307 made of silicone rubber, a hole communicating with the output extraction electrode 308 was formed in the back surface covering material. Note that the plug member 307 could be removed very easily using a finger, and no deposit of the sealing material resin was observed on the electrode 308 after the removal.

Further, the EVA of the back surface sealing material flowed during lamination, so that the opening end face of the steel plate 306 was completely covered with the flowed EVA. Thus, the steel plate 3
06 is covered with EVA,
In the high-temperature and high-humidity test (85 ° C./85% RH, 1000 hours) performed on the solar cell module, no separation between the steel plate 306 and the EVA at the opening end face was observed.

<Embodiment 2> In the solar cell module of Embodiment 2, the EVA sheet 303 has a vinyl acetate content of 2
A solar cell module was manufactured in exactly the same manner as the solar cell module of Example 1, except that a 5 wt%, melt flow rate of 4 was used, and a plug made of silicone rubber was not used.

In the solar cell module of Example 2, EV
Since the melt flow rate of A was small, the flow of EVA during lamination was small, and a hole could be formed without using a plug member.

On the other hand, similarly to the solar cell module of Example 1, the opening end face of the steel plate could be covered with the flowing EVA, and the same reliability was exhibited in the high temperature and high humidity test.

<Example 3> In the solar cell module of Example 3, up to the photovoltaic element group, the solar cell module was produced in the same manner as in Example 1.

With reference to FIG. 4, a description will be given of the steps after the step of forming the photovoltaic element group in the solar cell module of the third embodiment.

[Modularization] As shown in FIG. 4, a photovoltaic element group 401, an EVA sheet 402 (800 μm thick)
m, vinyl acetate content 33 wt%), tempered glass 4
03 (thickness 3.2 mm), polyvinyl fluoride (P
VF) A film 404 (thickness: 50 μm) is stacked in the order of glass 403 / EVA sheet 402 / photovoltaic element group 401 / EVA sheet 402 / polyvinyl fluoride film 404 from the light receiving surface side to form a solar cell module laminate 400. did.

The glass 403 on the light receiving surface side corresponds to the outermost surface member of the present invention, the EVA sheet 402 on the light receiving surface side corresponds to the surface sealing material of the present invention, and the polyvinyl fluoride film 404 of the present invention. The EVA sheet 402 on the back side corresponds to the backside member, and corresponds to the backside sealing material of the present invention, that is, the backside covering material other than the backside member.

When the solar cell module laminate 400 is formed, the output electrode 406 of the photovoltaic element group 401 is taken out.
In order to correspond to, the EVA sheet 402 and the polyvinyl fluoride film 404 as the back surface coating material,
Holes having a diameter of 6 mm and a diameter of 15 mm were respectively formed, and a plug member 405 made of fluororubber having a diameter of 6 mm and a thickness of 0.9 mm was arranged inside both holes.

The solar cell module laminate 400 formed as described above was heated and pressed at 150 ° C. for 30 minutes while being evacuated using a vacuum laminating apparatus. Thereafter, by removing the plug member 405 made of fluororubber, a hole communicating with the output extraction electrode 406 was formed in the back surface covering material. The solar cell module of the fourth embodiment is also the same as that of the first embodiment.
Like the solar cell module of No. 1, the plug member 405 could be removed very easily using a finger, and no adhesion of the sealing resin was observed on the electrode 406 after the removal.

The reliability in the high-temperature and high-humidity test was similar to that of the solar cell module of Example 1.

Comparative Examples 1 to 3 For comparison with the solar cell modules of Examples 1 to 3, the solar cell modules of Comparative Examples 1 to 3 were manufactured.

The solar cell modules of Comparative Examples 1 to 3 were compared with the solar cell modules of Examples 1 to 3, respectively.
It was manufactured by laminating a back coating material other than a steel plate without making a hole.

Then, a portion corresponding to the electrode of the back surface coating material was pierced with a cutter knife, and a diameter of 5 to 5 communicating with the electrode was obtained.
An 8 mm circular hole was formed.

When the electrodes of the solar cell modules of Comparative Examples 1 to 3 were observed, adhesion of EVA was observed. Also,
Scratches presumably due to the cutter knife were on the electrode surface.

Further, when the time required to form the holes was compared manually, it was found that the time required to form the holes in the solar cell module of Example 1 was about 5 to 10 times.

Further, in the solar cell module of Comparative Example 3, in the high-temperature and high-humidity test, peeling of the EVA and the polyvinyl fluoride film occurred from the end face of the opening portion cut out by the cutter knife.

Comparative Example 4 For comparison with the solar cell module of Example 3, a solar cell module of Comparative Example 4 was manufactured.

The solar cell module of Comparative Example 4 was manufactured in the same manner as the solar cell module of Example 3, except that a hole having a diameter of 6 mm was formed in the polyvinyl fluoride film.

In the solar cell module of Comparative Example 4,
The formation of the hole communicating with the output electrode is described in Example 3.
As in the case of the above, no adhesion of the sealing resin to the electrode portion was observed.

However, the end face of the opening of the EVA sheet and the polyvinyl fluoride film as the rearmost member is EV
Since it was not covered with A, peeling between the EVA and the polyvinyl fluoride film occurred at the opening in the high-temperature and high-humidity test.

[0095]

As described above, according to the present invention, since the residue of the sealing resin does not adhere to the electrode, no problem occurs in the soldering to the electrode due to the residue of the sealing resin. Thus, a high-quality solar cell module can be provided.

Further, since the holes communicating with the electrodes are formed before the laminating step, there is no need to pierce the back surface material with a jig such as a cutter knife after lamination. For this reason, there is no risk of damaging the electrode by a cutter knife or the like, and the quality of the solar cell can be further improved.

Further, since it is not necessary to form holes after lamination, the number of steps is reduced, and the throughput of solar cell module production can be improved.

Further, the adhesion between the backmost member and the backside sealing material is improved, so that it is difficult to peel off from the end of the opening, and the reliability of the terminal extraction portion for extracting electric output can be improved.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing an embodiment of a solar cell module according to the present invention.

FIG. 2 is a schematic sectional view showing another embodiment of the solar cell module according to the present invention, wherein (a) is a schematic sectional view before a laminating step, and (b) is a schematic structural view after laminating.

FIG. 3 is a schematic cross-sectional view of the solar cell module laminate of Example 1.

FIG. 4 is a schematic sectional view of a solar cell module laminate according to a third embodiment.

FIG. 5 shows the basic structure of a photovoltaic element, and (a)
Is a schematic sectional view, and (b) is a top view on the light receiving surface side.

[Explanation of symbols]

100, 200, 300, 400 Photovoltaic module laminate 101, 201, 301, 401 Photovoltaic element group 102, 202 Encapsulant resin 103, 203 Light transmissive member 104, 204 Sealing on back side of light receiving image side Material resin 105, 205 Insulating film 106a, b, 206a, b Opening 107, 209, 308, 406 Electrode 207, 307, 405 Plug member 208 Hole for output extraction 302, 303, 402 EVA sheet 304 ETFE film 305 PET Film 306 Steel plate 403 Glass plate 404 PVF film 501 Conductive substrate 502 Back reflection layer 503 Semiconductor photoactive layer 504 Transparent conductive layer 505 Current collecting electrode 506a Positive output terminal 506b Negative output terminal 507 Conductive adhesive 508 Solder

Continuation of the front page (72) Inventor Hidenori Shiozuka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Satoshi 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Hidetoshi Zenko 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term (reference) 5F051 AA05 BA14 BA17 BA18 CA15 EA01 EA17 GA02 JA04 JA05

Claims (10)

[Claims] 1. A photovoltaic element, a surface covering material comprising at least a transparent outermost member and a transparent surface sealing material covering a light receiving image side of the photovoltaic element, and non-light receiving of the photovoltaic element. In a solar cell module having at least the backmost member covering the image side and a backside covering material made of a backside sealing material, the backside covering material is provided in advance before a step of laminating the photovoltaic element, It has an opening communicating with an electrode disposed on the back surface of the photovoltaic element for output extraction, and the opening provided on the backmost member is provided on the back surface covering material other than the backmost member. A solar cell module characterized by being larger than an opening provided. 2. The solar cell module according to claim 1, wherein the rearmost member is made of one of a polymer resin film, a polymer resin plate, and a metal plate. 3. The inside of the opening has a melting point or softening point higher than the maximum temperature reached by the back surface covering material during the laminating step, and has a thickness substantially equal to the thickness of the entire back surface covering material. The solar cell module according to claim 1, further comprising a plug member having the solar cell module. 4. The solar cell module according to claim 3, wherein said plug member is made of an elastic body. 5. The solar cell module according to claim 4, wherein said elastic body is made of silicone rubber or fluorine rubber. 6. A photovoltaic element, a surface covering material comprising at least a transparent outermost member and a transparent surface sealing material covering a light receiving image side of the photovoltaic element, and a non-light receiving part of the photovoltaic element. In a method of manufacturing a solar cell module having at least a rearmost surface member covering the image side and a rear surface covering material composed of a rear surface sealing material, the rear surface covering material is disposed on the rear surface of the photovoltaic element for extracting electric output. Providing an opening that is larger than the opening provided in the back surface covering member other than the back surface member, and then laminating the photovoltaic element. A method for manufacturing a solar cell module, comprising: 7. The method for manufacturing a solar cell module according to claim 6, wherein said rearmost member is made of any one of a polymer resin film, a polymer resin plate, and a metal plate. 8. The inside of the opening has a melting point or softening point higher than the maximum temperature reached by the back surface covering material during the laminating step, and has a thickness substantially equal to the thickness of the entire back surface covering material. The method for manufacturing a solar cell module according to claim 6, wherein a plug member having the plug is provided. 9. The method according to claim 8, wherein the plug member is made of an elastic body. 10. The method for manufacturing a solar cell module according to claim 9, wherein said elastic body is made of silicone rubber or fluorine rubber.