JP2005072567A - Manufacturing method of solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing method of solar cell module, of which solar cell elements are not damaged by heating or pressing, which can sufficiently remove air bubbles within the solar cell module and which has proper appearance. <P>SOLUTION: In the manufacturing method of a solar cell module including steps of stacking at least a first surface member, a first surface-sealing material film, photovoltaic elements, a second surface-sealing material film, and a second surface member , and heating and pressing them, the first-sealing material film and the second surface sealing material film are contact with the photovoltaic element respectively, at least one of the surfaces of the first surface-sealing material film and the second surface-sealing material film contacting the solar cell elements is provided with trench shaped concaves which are continued from one end of the surface periphery to the other end, and the range of the area of the trench shaped concaves is between 5 to 40 % of the surface area of the first or second surface-sealing material film on which the trench shaped concaves are formed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a method for manufacturing a solar cell module, and more particularly to a method for efficiently manufacturing a solar cell module having a good appearance without damage of a photovoltaic element due to heat and pressure.

Conventionally, a crystalline solar cell (photovoltaic element) using a single crystal or a polycrystal and a chromatic solar cell module using a thermoplastic resin as a filler generally have a rectangular lower plate glass (the lowermost layer) It has a laminated structure in which a thermoplastic resin sheet, a photovoltaic element, a thermoplastic resin sheet, and a rectangular upper plate glass (non-light-receiving surface glass) are laminated in this order on the light-receiving surface side glass). Here, as the thermoplastic resin sheet, a sheet of ethylene / vinyl acetate copolymer, polyvinyl butyral, polyurethane or the like is generally used.
In such a solar cell module manufacturing method, a predetermined pressure is applied from the lower surface of the lower glass plate and the upper surface of the upper glass plate by reducing the pressure between the lower glass plate and the upper glass plate at a predetermined temperature and atmosphere. (Hereinafter sometimes referred to simply as “pressurization”), the lower glass plate, the upper glass plate, and the photovoltaic element are brought into close contact with each other through a thermoplastic resin to produce a luminescent solar cell module.

More specifically, the laminate as shown in FIG. 1 is put into a sealing bag as shown in FIG. A method (airbag method) in which the electromotive force element and the thermoplastic resin are pressed and adhered is used. In addition, as shown in FIG. 3, a method of placing the laminate on a plate, placing a silicone rubber sheet on the laminate and fixing the periphery, and pressurizing and sticking the internal air under reduced pressure (single chamber method) ) Etc. are used.
However, in recent years, photovoltaic devices such as crystalline solar cells tend to be thin due to demands for resource saving and cost reduction, and thus the strength of these devices tends to decrease. Therefore, the above-described manufacturing method has a problem that the photovoltaic element is damaged when the thermoplastic resin is hard and the photovoltaic element is pressurized during vacuum suction. In addition, since the photovoltaic element is generally smaller than the lower plate and the upper plate, the gap shown in FIG. 1 exists in the periphery of the photovoltaic element. There was a problem that air in the gap could not be removed, and bubbles remained even after the front surface member, the back surface member, and the photovoltaic element were pressed and adhered through the thermoplastic resin, resulting in poor appearance.

As a manufacturing method for solving these problems, a double chamber system in which a laminate in which a photovoltaic element is sandwiched between a thermoplastic resin and a glass plate, etc. has an upper chamber and a lower chamber, and the boundary is partitioned by a silicone rubber sheet. A method has been proposed in which a front surface member, a back surface member, and a photovoltaic element are pressed and adhered through a thermoplastic resin by heating under reduced pressure using a vacuum laminating apparatus (see, for example, Patent Documents 1 and 2). .
Generally, these apparatuses have a plate equipped with a heating device in a lower chamber, and the laminate is placed on the plate, and a silicone rubber sheet is overlaid thereon. Thereafter, the laminate and the silicone rubber sheet are sandwiched between the upper chamber and the lower chamber, the upper and lower chambers are depressurized, and the inside of the laminate is heated to 1.3 kPa or less. In the heated state, the pressure in the upper chamber is increased to increase the pressure, and the front and back members and the photovoltaic element are brought into close contact with each other through a thermoplastic resin. According to this method, since the thermoplastic resin is pressed in a softened state by heating, even if the photovoltaic element has low strength, it does not cause damage such as cracking, and the inside of the laminate is sufficiently Therefore, air is not collected in the gap.
However, since the double-chamber type vacuum laminating apparatus has a vacuum chamber, for example, a large-scale apparatus is required for sealing a large-sized solar cell module for buildings and the like. The limit is to produce a solar cell module of about 2 m. In order to produce a larger solar cell module using a double chamber type vacuum laminating apparatus, a great investment in equipment is required, which is not necessarily a preferable method from the viewpoint of economy.

On the other hand, a solar cell module in which at least one of a glass fiber nonwoven fabric and an organic resin fiber nonwoven fabric or both of them are loaded in the above-described laminate has been proposed in order to solve the problem of the generation of air bubbles ( (See Patent Document 3).
However, since the melting points of the glass fiber nonwoven fabric and the organic resin fiber nonwoven fabric are both higher than the melting point and the crosslinking temperature of the thermoplastic resin sandwiching the photovoltaic element, the fiber shape of the nonwoven fabric remains, and the appearance of the solar cell module There is a problem that damages.

Further, the solar cell includes a substantially plate-like solar cell element, a substantially plate-like base material having an opening for inserting the solar cell element, and a support substrate that supports the solar cell element and the base material. A solar cell module in which a filler is disposed between an element, the base material, and the support substrate has been proposed (see Patent Document 4).
However, when a plurality of solar cell elements are connected by a tab wire, a base material having an opening for inserting the solar cell element is in contact with the tab wire, and the solar cell element and the filler are subjected to heat pressure bonding. In some cases, excessive stress is generated in the vicinity of the tab line of the battery element, and damage to the solar cell element such as cracking may occur.

Furthermore, in the solar cell module in which the light-transmitting substrate, the front surface sealing material film, the photovoltaic element, the back surface sealing material film, and the back surface protective film are laminated, the front surface sealing material film and the back surface sealing material film are formed on the surface. There has been proposed a solar cell module having an uneven structure, and the height of the uneven portion occupies 10 to 50% of the total thickness of the sealing material film (see Patent Document 5).
However, when so-called embossing is performed so that the height of the concavo-convex portion is 10 to 50% of the total thickness of the encapsulant film, the area of the recess becomes 50% or more with respect to the encapsulant film surface. In the double chamber type vacuum laminator, the bubbles can be removed, but in the single chamber type vacuum laminator, the convex part is crushed by pressurization, and the air cannot be sufficiently deaerated by vacuum suction. It is difficult to remove the sufficient amount. In addition, the convex portion is 50% or less, and the stress at the time of thermocompression bonding is concentrated, so that excessive stress is generated and the photovoltaic element is damaged such as cracking.
In addition, a solar cell sealing film has been proposed in which a number of recesses are formed on the surface of the sealing film by embossing, and further, a communication path communicating between the recesses is provided (patent). Reference 6).
However, since the communication path is narrow, it is difficult to sufficiently remove bubbles in the single chamber type vacuum laminating apparatus as described above.

Japanese Patent Laid-Open No. 10-214987 JP-A-11-254526 Japanese Patent Laid-Open No. 11-112007 JP 2001-60709 A JP 2002-134768 A JP 2002-185027 A

  An object of the present invention is to provide a method for manufacturing a solar cell module of a large size at low cost using a conventional laminated glass manufacturing facility without making a large capital investment under such circumstances. To do.

  As a result of intensive studies to achieve the above object, the present inventors have determined that the surface sealing material film and the back surface sealing material film are in contact with the photovoltaic elements on the surface from one end to the other end of the surface. It has been found that the above-mentioned problem can be solved by providing a groove-like recess that is continuous up to. The present invention has been completed based on such findings.

That is, the present invention
(1) A method for manufacturing a solar cell module in which at least a surface member, a surface sealing material film, a photovoltaic element, a back surface sealing material film, and a back surface member are laminated and heated and pressurized, wherein the surface sealing material film and the back surface The sealing material film is in contact with the photovoltaic element, and at least one of the surface of the front surface sealing material film in contact with the photovoltaic element and the surface of the back surface sealing material film in contact with the photovoltaic element is formed around the periphery of the surface. It has a groove-shaped concave portion continuous from one end to the other end, and the area of the groove-shaped concave portion is 5 to 5 with respect to the surface area of the surface sealing material film or the back surface sealing material film on which the groove-shaped concave portion is formed. A method for producing a solar cell module, characterized by being in the range of 40%;
(2) The method for producing a solar cell module according to (1), wherein there are a plurality of the groove-shaped recesses and the distance between them is 5 to 35 mm.
(3) The method for manufacturing a solar cell module according to any one of (1) and (2), wherein the depth of the groove-shaped recess is 0.3 mm or more,
(4) The manufacturing method of the solar cell module according to any one of (1) to (3), wherein the groove-shaped recess has a width of 1 to 3 mm.
(5) The method for producing a solar cell module according to any one of (1) to (4), wherein the photovoltaic elements are plural and connected by tab wires.
(6) A surface member, a surface sealing material film, a photovoltaic element, a back surface sealing material film, and a back surface member are laminated in this order, and the surface sealing material film and the groove shape having the groove-shaped recesses are formed by a vacuum heating device. Of the backside sealing material film having the recess, the heating material is heated under normal pressure at a temperature 5 to 20 ° C. lower than the melting point of the sealing material film having a lower melting point, and then reduced to 3 kPa or less at the same temperature. The method for producing a solar cell module according to any one of the above (1) to (5), wherein heating is performed at a temperature 8 to 20 ° C higher than the melting point of the sealing material film having a higher melting point,
(7) The method for producing a solar cell module according to (6), wherein the heating is performed at a temperature equal to or higher than a crosslinking temperature of the front surface sealing material film and the back surface sealing material film after heating in the reduced pressure state,
Is to provide.

  According to the method for manufacturing a solar cell module of the present invention, the conventional air bag type or single chamber type manufacturing equipment is used, the photovoltaic element is not damaged by heating and pressurization, and bubbles inside the solar cell module are generated. A solar cell module with a sufficiently removed appearance can be manufactured. Moreover, since a large heating furnace can be used, a large-sized solar cell module can be manufactured efficiently.

The method for manufacturing a solar cell module of the present invention is a method for manufacturing a solar cell module in which at least a surface member, a surface sealing material film, a photovoltaic device, a back surface sealing material film, and a back surface member are laminated and heated and pressurized. The surface sealing material film and the back surface sealing material film are in contact with the photovoltaic element, and the surface of the surface sealing material film is in contact with the photovoltaic element and the surface of the back surface sealing material film is in contact with the photovoltaic element. At least one has a groove-like recess that is continuous from one end to the other end of the circumference of the surface.
Here, the surface member is preferably a member that transmits sunlight in order to normally operate the photovoltaic element, and transparent glass, a plastic plate, a plastic film, or the like is preferably used. On the other hand, the back member supports the photovoltaic element and is not particularly limited, and a translucent substrate such as glass can be used in the same manner as the front member. In addition, when a resin film such as nylon film or polyester, moisture resistance, and weather resistance are required, an aluminum laminated tedlar film or the like can be used. In addition, a ceramic sheet and a metal sheet can also be used.
Although it does not specifically limit as thickness of a surface member and a back surface member, It is preferable that it is the range of 2-15 mm. When the thickness is 2 mm or more, the strength of the solar cell module can be sufficiently ensured, and when it is 15 mm or less, there is an advantage that it is lightweight. From the above viewpoint, the range of 4 to 12 mm is more preferable, and the range of 5 to 8 mm is particularly preferable.

  The photovoltaic element used in the present invention is not particularly limited, and any of single crystal type, polycrystalline type, and amorphous type can be used. It is suitable as a method for producing a solar cell module using a crystalline crystal photovoltaic element. A plurality of photovoltaic elements may exist and may be electrically connected by a tab line. When photovoltaic elements are connected by tab wires, the tab wire portions are thicker than other portions, so stress is often concentrated. It is conceivable that the power element is bent and cracked. As described later, the manufacturing method of the present invention softens and deforms the front surface sealing material film and / or the back surface sealing material film, wraps the tab wire, eliminates the difference in thickness, and concentrates stress on the tab wire. Distributed. Therefore, the manufacturing method of the present invention is particularly effective when the photovoltaic elements are connected by tab wires.

Next, the material of the front surface sealing material film and the back surface sealing material film can be softened by heating so as to wrap the tab wire and eliminate a step due to the tab wire. The property of sealing the electromotive force element is required. In addition, in the case of a solar cell module of a type in which a plurality of photovoltaic elements are connected by a tab line, fluidity that can fill a gap between the photovoltaic elements is required. Further, it is necessary that the photovoltaic element can be bonded to the front surface member and the back surface member. The material for the front surface sealing material film and the back surface sealing material film is not particularly limited as long as these requirements are satisfied, but in general, ethylene / vinyl acetate copolymer, polyvinyl butyral, polyurethane, etc. A transparent thermoplastic resin sheet is used. Further, the material for the front surface sealing material film and the back surface sealing material film may be the same or different, but it is preferable to use the same material in consideration of ease of manufacturing.
Moreover, it is although it does not specifically limit as thickness of a surface sealing material film | membrane and a back surface sealing material film | membrane, It is preferable that it is the range of 0.6-1.2 mm. If it is 0.6 mm or more, sufficient strength can be secured to protect the photovoltaic device, and if it is 1.2 mm or less, it can meet the recent request that the solar cell module be lightweight. Is possible. From the above viewpoint, the range of 0.6 to 1.0 mm is more preferable, and the range of 0.8 to 1.0 mm is particularly preferable.

As shown in FIG. 1, the solar cell module according to the present invention is illustrated by laminating a surface member, a surface sealing material film, a photovoltaic element, a back surface sealing material film, and a back surface member. It is a thing. In the present invention, the front surface sealing material film and the back surface sealing material film are in contact with the photovoltaic element, respectively, and the front surface and back surface sealing material film photovoltaic elements in contact with the photovoltaic element of the front surface sealing material film At least one of the surfaces in contact with the surface has a groove-like recess that is continuous from one end to the other end of the periphery of the surface. A groove-like recess that is continuous from one end of the circumference to the other end means a state in which a groove is continuously cut from one side to the other side when the surface sealing material film is square, for example. 4 shows a case where grooves are continuously cut from the ridge line a toward the ridge line b, and a case where grooves are continuously cut from the ridge line a toward the ridge line c as shown in FIG. In addition, a case in which a groove is cut from one side toward the inside of the square and returned to the one side is also included.
The case where the surface sealing material film is circular includes a case where grooves are continuously cut from one end to the other end of the circumference as shown in FIG.

Moreover, the groove-shaped recessed part should just be continuously connected from the one end of the circumference to the other end, and does not necessarily need to be formed linearly. For example, the groove-like concave portion may have a jagged shape or a curved shape. Moreover, the some groove-shaped recessed part may cross, for example, a grid | lattice form may be sufficient. The shape of the remaining convex part which cut | disconnected the groove-shaped recessed part is not specifically limited, For example, the shape which becomes a tortoiseshell shape or circular is also included.
The cross-sectional shape of the groove-shaped recess may be any of a substantially square shape, a substantially semi-circular shape, a substantially triangular shape, a substantially U-shaped shape, and other irregular shapes, but in order to sufficiently exert the effects of the present invention, A quadrangle is preferred.
In addition, when the groove-shaped recess is formed linearly and the direction of the groove-shaped recess is one direction, and the photovoltaic elements are connected by tabs, the groove-shaped recess The direction and the direction of the tab line are preferably substantially vertical. In the substantially vertical direction, the tab wire does not fit into the groove-shaped recess, so that stress is not concentrated on a part of the photovoltaic element, and damage such as cracking of the photovoltaic element does not occur. .
By providing the groove-shaped recess on the surface of the encapsulant film as described above, a path through which bubbles in the solar cell module escape is secured when the photovoltaic element and the encapsulant film are thermocompression bonded.
The groove-shaped recess may be provided on either the surface of the front surface sealing material film in contact with the photovoltaic element or the surface of the back surface sealing material film in contact with the photovoltaic element, and achieves the effect of the present invention.

It is essential that the groove-shaped recess has an area of 5 to 40% with respect to the area of the surface of the sealing material film. If it is 5% or more, bubbles can be effectively removed from the solar cell module. On the other hand, if it is 40% or less, sufficient stress is applied to the photovoltaic elements and the tab wires connecting the photovoltaic elements. It is dispersed and does not cause damage such as cracking of the photovoltaic element.
The area of the groove-shaped recess is preferably in the range of 5 to 20% with respect to the area of the surface of the sealing material film.
The depth of the groove-shaped recess is not particularly limited as long as the bubbles in the solar cell module can be effectively removed, and is appropriately determined depending on the size and thickness of the solar cell module, but usually 0.3 mm or more, Preferably it is the range of 0.3-0.5 mm.
Moreover, it is preferable that the width | variety of this groove-shaped recessed part is the range of more than 1 mm and 3 mm or less, and when the groove-shaped recessed part is provided with two or more on the surface of the sealing material film, these space | intervals are 5-35 mm. A range is preferable. Here, the interval between the groove-shaped recesses means a distance from one groove-shaped recess piece to the next groove-like recess piece as shown in FIG. As described above, it is essential that the groove-like recesses have a range of 5 to 40% of the area of the surface of the sealing material film. However, the width and interval of these groove-like recesses are within the above range. By doing so, the above-mentioned area ratio can be easily achieved. From the above viewpoint, the width of the groove-like recesses is more preferably in the range of more than 1 mm and 2 mm or less, and the interval of the groove-like recesses is more preferably in the range of 10-20 mm.
Although there is no restriction | limiting in particular as a method of forming the said groove-shaped recessed part, It can manufacture at low cost by processing the sealing material film | membrane surface with a heating roller etc.

In the production method of the present invention, as described above, at least the front surface member, the front surface sealing material film, the photovoltaic element, the back surface sealing material film, and the back surface member are laminated, and then heated and pressurized to produce the photovoltaic element. And the front surface member and the back surface member are bonded through the front surface sealing material film and the back surface sealing material film. As a method for heating and pressurizing, a known method can be used. In this method, a vacuum heating apparatus which is usually used when producing laminated glass or the like can be used.
The heating / pressurizing method is not particularly limited, but preferably under normal pressure, up to 5 to 20 ° C. lower than the melting point of the front surface sealing material film and / or the back surface sealing material film on which the groove-like recesses are formed. Is preferably heated at an average temperature increase rate of 1 to 5 ° C./min, and more preferably at an average temperature increase rate of 1.5 to 3 ° C./min. By this heating, the front surface sealing material film and / or the back surface sealing material film is softened. Here, when the materials of the front surface sealing material film and the back surface sealing material film are different and a groove-like recess is formed in only one of them, the melting point of the sealing material film forming the groove-like recess is 5 Means a temperature lower by -20 ° C. Further, when the materials of the front surface sealing material film and the back surface sealing material film are different and both have groove-shaped recesses, the melting point of the sealing material film made of a material having a lower melting point is 5 to 5 This means that the temperature is lowered by 20 ° C. Here, when the materials of the front surface sealing material film and the back surface sealing material film are different, the difference in melting point between these materials is preferably within 10 ° C. When the temperature reaches 5 to 20 ° C. lower than the melting point of the sealing material film, vacuum suction may be performed immediately as described later, or heating may be performed at the same temperature for about 2 to 5 minutes.

Next, the pressure is reduced to 3 kPa or less while maintaining the temperature 5 to 20 ° C. lower than the melting point of the front surface sealing material film and / or the back surface sealing material film. At this temperature, the sealing material film is softened, but does not reach a fluidized state, so that the groove-shaped recess is not blocked. In particular, by setting the width, depth, and interval of the groove-like recesses in the ranges as described above, the blockage of the groove-like recesses is further suppressed. Accordingly, air in the gap existing in the vicinity of the photovoltaic element is degassed through the groove-shaped recess during this decompression process. It is more preferable that the pressure is further reduced to 1.3 kPa or less from the viewpoint of performing degassing more sufficiently.
After sufficient deaeration, the average rise in temperature is 8 to 20 ° C. higher than the melting point of the front surface sealing material film and / or the back surface sealing material film, preferably 1 to 5 ° C./min. It is preferable to heat at a temperature rate, and more preferably at an average temperature rise rate of 1.5 to 3 ° C./min. By this heating, the photovoltaic element is sealed, and the photovoltaic element and the front surface member and the back surface member are bonded via the front surface sealing material and the back surface sealing material. After reaching a temperature 8-20 ° C. higher than the melting point of the sealing material film, depending on the material of the front surface sealing material film and the back surface sealing material film, immediately heat above the temperature at which these materials cross-link, The encapsulant film can be cured, and in the case of a resin having no crosslinkability, it is about 5 to 15 minutes at a temperature 10 to 20 ° C. higher than the melting point of the encapsulant film before the curing treatment. Heat treatment can also be performed. The thermosetting treatment such as cross-linking may be performed after the photovoltaic element is sealed, after the photovoltaic element is bonded to the front surface member and the back surface member, and then cooled.

According to the production method of the present invention, bubbles in the solar cell module can be removed as described above, and damage such as cracking of the photovoltaic element can be suppressed. There is also an effect of preventing. The reason why the photovoltaic device is displaced is that when the material of the encapsulant film is vacuum-sucked, the front surface member or back surface member such as glass is partially deformed to form an inclined portion, and the flow of the encapsulant film material When the material of the sealing material film moves to the space between the photovoltaic elements, the lateral force due to the inclination is applied to the photovoltaic elements and the photovoltaic elements are displaced. It is.
In the manufacturing method of the present invention, since the material of the encapsulant film is softened before being vacuumed, the front surface member or the back surface member such as glass is not partially deformed during vacuum suction, and the photovoltaic element is shifted. There is nothing.

  EXAMPLES Next, although an Example demonstrates this invention further in detail, this invention is not limited at all by this example.

Example 1
A rectangular sheet having a thickness of 0.8 mm and a size of 1000 mm × 2000 mm made of an ethylene acetate / vinyl copolymer (manufactured by Bridgestone Corporation, bridge temperature 150 ° C., melting point 76 ° C., hereinafter abbreviated as “EVA”). Using a heating roller, as shown in FIG. 7, groove-like recesses having a width of 2 mm and a depth of 0.4 mm were formed at intervals of 17 mm to produce a surface sealing material film. Next, as shown in FIG. 8, the surface sealing material film is arranged on the lower glass so that the groove-shaped recesses are on the top, and the photovoltaic elements are placed on the surface so that the interval is 15 mm. The cell strings were connected in series with a tab line, and five cell strings were arranged so that the interval was 40 mm. A laminated body was prepared by arranging a back surface sealing material film made of a square EVA sheet having a thickness of 0.8 mm and a size of 1000 mm × 2000 mm, and an upper plate glass without a groove-like recess. At this time, the area of the groove-shaped recess was 11.8% with respect to the area of the surface of the surface sealing material film. The photovoltaic element used here was a polycrystalline type, and had a size of 150 mm × 155 mm, an average thickness of 0.33 mm, and a 1/1000 probability bending strength of 1.6 MPa.
Attach a thermocouple between the surface sealing material film and the back surface sealing material film of the laminate (gap), put in an airbag, and heat at an average temperature increase rate of 1.5 ° C./min. Vacuum suction was started when the thermocouple showed 65 ° C., and the pressure in the airbag was set to 1.5 kPa. Thereafter, the laminate was heated at an average temperature increase rate of 1.5 ° C./min until reaching 90 ° C., and then the laminate was taken out from the airbag. Subsequently, it heated at the average temperature increase rate of 1.5 degree-C / min to 150 degreeC which is the bridge | crosslinking temperature of a surface sealing material film | membrane, and took out from the furnace. There was no crack in the photovoltaic element, and a solar cell module in which no bubbles remained was obtained.

Comparative Example 1
A solar cell module was obtained in the same manner as in Example 1 except that an EVA sheet having no groove-like recess was used as the surface sealing material film. Although cracking of the photovoltaic element did not occur, there were residual bubbles at the peripheral edge and transmission part of the photovoltaic element, so that it could not be used as a commercial product.

Example 2
An EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm are formed at intervals of 32 mm is used as a surface sealing material film, and the temperature at which vacuum suction is started is set to 60 ° C. By the method, a solar cell module was obtained. The area of the groove-shaped recess was 6.3% with respect to the area of the surface of the surface sealing material film. There was no crack in the photovoltaic element, and a solar cell module in which no bubbles remained was obtained.

Comparative Example 2
A solar cell module was obtained in the same manner as in Example 2 except that an EVA sheet having no groove-like recess was used as the surface sealing material film. Although cracking of the photovoltaic element did not occur, there were residual bubbles at the peripheral edge and transmission part of the photovoltaic element, so that it could not be used as a commercial product.

Example 3
An EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm are formed at intervals of 12 mm is used as a surface sealing material film, and the temperature at which vacuum suction is started is set to 70 ° C. By the method, a solar cell module was obtained. The area of the groove-shaped recess was 16.7% with respect to the surface area of the surface sealing material film. There was no crack in the photovoltaic element, and a solar cell module in which no bubbles remained was obtained.

Comparative Example 3
A solar cell module was obtained in the same manner as in Example 3 except that an EVA sheet having no groove-like recess was used as the surface sealing material film. Although cracking of the photovoltaic element did not occur, there were residual bubbles at the peripheral edge and transmission part of the photovoltaic element, so that it could not be used as a commercial product.

Example 4
An EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm are formed at intervals of 7 mm is used as a surface sealing material film, and the temperature at which vacuum suction is started is set to 70 ° C. By the method, a solar cell module was obtained. The area of the groove-shaped recess was 28.6% with respect to the surface area of the surface sealing material film. There was no crack in the photovoltaic element, and a solar cell module in which no bubbles remained was obtained.

Example 5
An EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm were formed at intervals of 5 mm was used as the surface sealing material film, and the same temperature as that of Example 1 except that the temperature at which vacuum suction was started was set to 60 ° C. By the method, a solar cell module was obtained. The area of the groove-shaped recess was 40% with respect to the area of the surface of the surface sealing material film. There was no crack in the photovoltaic element, and a solar cell module in which no bubbles remained was obtained.

Comparative Example 4
A solar cell module was obtained in the same manner as in Example 5 except that an EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm were formed at intervals of 52 mm was used as the surface sealing material film.
The area of the groove-shaped recess was 3.8% with respect to the area of the surface of the surface sealing material film. Although cracking of the photovoltaic element did not occur, there were residual bubbles at the peripheral edge and transmission part of the photovoltaic element, so that it could not be used as a commercial product.

Comparative Example 5
A solar cell module was obtained in the same manner as in Comparative Example 4 except that the temperature at which vacuum suction was started was 55 ° C. Although no residual bubbles were generated, 15% of the photovoltaic elements were cracked and could not be used as commercial products.

Comparative Example 6
A solar cell module was obtained in the same manner as in Comparative Example 5 except that an EVA sheet in which groove-like recesses having a width of 2 mm and a depth of 0.4 mm were formed at intervals of 102 mm was used as the surface sealing material film. The area of the groove-shaped recess was 2.0% with respect to the area of the surface of the surface sealing material film. Cracks occurred in 15% of the photovoltaic elements, and bubbles remained in the periphery and the transmission part of the photovoltaic elements, so that they could not be used as commercial products.

Comparative Example 7
A solar cell module was obtained in the same manner as in Comparative Example 6 except that the temperature at which vacuum suction was started was 50 ° C. Although no residual bubbles were generated, 40% of the photovoltaic elements were cracked and could not be used as commercial products.

Comparative Example 8
A solar cell module was obtained in the same manner as in Comparative Example 7 except that an EVA sheet having no groove-like recess was used as the surface sealing material film. Cracks occurred in 40% of the photovoltaic elements, and there were residual bubbles at the periphery and transmission part of the photovoltaic elements, so that they could not be used as commercial products.

It is a schematic diagram of the laminated body which comprises a solar cell module. It is a schematic diagram which shows an airbag system. It is a schematic diagram which shows a single chamber system. It is a schematic diagram which shows the groove-shaped recessed part on a sealing material film. It is a schematic diagram which shows the groove-shaped recessed part on a sealing material film. It is a schematic diagram which shows the groove-shaped recessed part on a sealing material film. It is a schematic diagram which shows the groove-shaped recessed part on a sealing material film. It is a schematic diagram which shows the laminated structure of a solar cell module.

Explanation of symbols

1. Surface member (lower glass)
2. Surface sealing material film (thermoplastic resin film)
3. Photovoltaic element (solar cell)
4). Back surface sealing material film (thermoplastic resin film)
5). Back member (upper glass)
6). Gap 7. Laminated body 8. Deaeration port 9. Airbag 10. Fastener 11. Silicone rubber sheet 12. Plate 13. Tab line 14. Groove-shaped recess

Claims (7)

  A method of manufacturing a solar cell module, wherein at least a surface member, a surface sealing material film, a photovoltaic element, a back surface sealing material film, and a back surface member are laminated and heated and pressurized, wherein the surface sealing material film and the back surface sealing material Each of the films is in contact with the photovoltaic element, and the surface sealing material film has at least one of the surface in contact with the photovoltaic element and the surface of the back surface sealing material film in contact with the photovoltaic element. 5 to 40% of the area of the surface sealing material film or the back surface sealing material film on which the groove-shaped recess is formed and the groove-shaped recess has an area continuous to the end. A method for manufacturing a solar cell module, characterized by being in a range.   The method for manufacturing a solar cell module according to claim 1, wherein there are a plurality of the groove-like recesses, and an interval between them is 5 to 35 mm.   The method for manufacturing a solar cell module according to claim 1, wherein a depth of the groove-shaped recess is 0.3 mm or more.   The method for manufacturing a solar cell module according to any one of claims 1 to 3, wherein a width of the groove-shaped recess is more than 1 mm and 3 mm or less.   The method for manufacturing a solar cell module according to claim 1, wherein the photovoltaic elements are plural and connected by a tab wire.   A surface member, a surface sealing material film, a photovoltaic device, a back surface sealing material film, and a back surface member are laminated in this order, and the surface sealing material film having the groove-shaped recess and the groove-shaped recess are provided by a vacuum heating device. Of the backside sealing material film, it is heated under normal pressure at a temperature 5 to 20 ° C. lower than the melting point of the sealing material film having a lower melting point, and then reduced to 3 kPa or less at the same temperature. The method for producing a solar cell module according to any one of claims 1 to 5, wherein heating is performed at a temperature 8 to 20 ° C higher than a melting point of the sealing material film. The method for manufacturing a solar cell module according to claim 6, wherein after the heating in the reduced pressure state, heating is performed to a temperature equal to or higher than a crosslinking temperature of the front surface sealing material film and the back surface sealing material film.

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