JP2007048861A - Manufacturing method for solar cell module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for sealing a solar cell module capable of largely reducing a manufacturing cost by enabling a continuous production in a high throughput by a simple production facility. <P>SOLUTION: The manufacturing method for the solar cell module has a sealing process in which at least one surface of a solar cell element is supplied with a heated and melted sealing resin, and the sealing resin is pressed by a roller under the melted state of the sealing resin. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a solar cell module, and more particularly to a method for sealing a solar cell element.

  The solar cell module 100 called a super straight structure shown in FIG. 10 is generally produced by a so-called “vacuum laminating method”. That is, as shown in FIG. 9, first, a glass substrate 91, fillers 92 and 93 formed into a sheet shape made of ethylene-vinyl acetate (EVA), a solar cell element 94, and a back surface as a protective film. Each of the sheets 95 is laminated. Then, after these are vacuum degassed, the EVA fillers 92 and 93 are melted at a high temperature of about 150 ° C., and heated and crosslinked for about 30 minutes to 1 hour.

  A solar cell module 110 called a substrate structure using a surface film 111 such as a fluororesin film on a light receiving surface and a back surface steel plate 113 such as a galvalume steel plate shown in FIG. Manufactured by.

However, with this method currently in use,
(1) Since it is necessary to form the filler into a sheet, the material cost of the filler is high.
(2) Since the filler is a molded sheet, dust and dust are likely to adhere in the laminating operation.
(3) In the molded sheet, since the additive contained in the filler is easily removed, the storage period is short.
(4) Since the laminating apparatus is a vacuum apparatus, it is expensive.
(5) Since the lamination method is a batch method, there is a limit to the processing capacity, and productivity is not increased.
There was a drawback.

  In order to solve the above problem, Patent Documents 1 and 2 disclose a method of applying a polyisobutylene resin by extrusion with an extruder equipped with a die and sealing a solar cell element.

  However, in the above method, the thickness of the resin applied from the die is likely to be uneven with respect to the width direction of the die, and as a result, the thickness of the resin applied on the glass substrate is likely to be uneven. there were. Also, the higher the coating speed, the more uneven the thickness of the resin, so in order to eliminate the unevenness of the location, it is necessary to set the coating speed slower. However, if the coating speed decreases, the productivity will not increase. There was a point. Here, if the thickness of the resin applied on the glass substrate is uneven, there is a drawback that bubbles are likely to remain between the resin and the solar cell element when the solar cell element is placed on the applied resin. Therefore, there are problems in appearance and reliability.

  Patent Document 3 discloses a method in which a film-like protective member and an adhesive resin are laminated on both sides of a solar cell element using a hot roll.

  However, in this method, after the adhesive resin is once formed into a film shape, the adhesive resin is dissolved and laminated with a heated roll, and the time during which the adhesive resin and the roll are in contact is very short. Therefore, there is a problem that the adhesive resin is not easily melted. Therefore, when the solar cell element has irregularities such as electrodes, there is a drawback that it is difficult to follow the irregularities, and bubbles accumulate on the boundary of the irregularities of the solar cell element. Further, in order to completely dissolve the adhesive resin, it is necessary to slow down the feed rate of the roll, and productivity is not improved. Further, since the adhesive resin is supplied in the form of a film, there are the same defects as the defects (1) to (3) in the case where a molded sheet is used as the filler.

Japanese Patent No. 3531875 Japanese Patent Laid-Open No. 6-151938 JP 2003-273374 A

  In view of the circumstances as described above, it is an object of the present invention to provide a method for sealing a solar cell module that enables high-throughput continuous production with simple production equipment and can greatly reduce the manufacturing cost.

  Also, when the sealing resin is crimped to the solar cell element, the followability of the sealing resin to the irregularities on the surface of the solar cell element is improved, and a solar cell module having an excellent appearance with no voids or bubbles remaining is manufactured. The purpose is to do.

  Furthermore, the adhesion between the solar cell element and the sealing resin is improved, and the solar cell element and the sealing resin are peeled off even after long-term outdoor exposure, coupled with the absence of the voids and bubbles described above. An object is to provide a highly reliable solar cell module.

  That is, the method for producing a solar cell module of the present invention supplies a sealing resin that is heated and melted to at least one surface of a solar cell element, and the sealing resin is in a molten state while the sealing resin is in a molten state. It has the sealing process which pressurizes with a roller.

  According to the present invention, high-throughput continuous production is possible with simple production facilities, and the manufacturing cost of the solar cell module can be greatly reduced. That is, since the sealing resin in a sufficiently molten state is pressure-bonded to the solar cell element, it is possible to expect the adhesiveness between the sealing resin and the solar cell element in a short time, and the throughput is higher than that of the conventional roll laminate. Can be increased.

  Also, when the sealing resin is crimped to the solar cell element, the followability of the sealing resin to the irregularities on the surface of the solar cell element is improved, and a solar cell module having an excellent appearance with no voids or bubbles remaining is manufactured. can do. That is, since the sealing resin in a molten state is pressed and attached to the surface of the solar cell element, the sealing resin flows along the unevenness on the surface of the solar battery cell, and the unevenness is filled with the resin, and voids and bubbles are formed. Residue is suppressed. In particular, it has a remarkable effect when sealing solar cell elements having irregularities of 100 μm or more on the surface, such as current collecting electrodes, bus bar electrodes, or interconnectors.

  Furthermore, the adhesion between the solar cell element and the sealing resin is improved, and the solar cell element and the sealing resin are peeled off even after long-term outdoor exposure, coupled with the absence of the voids and bubbles described above. Therefore, it is possible to provide a highly reliable solar cell module.

  In addition, since the sealing resin is supplied in a molten state, it is possible to solve the disadvantages in the case of using the sealing resin formed into a sheet shape, and to manufacture a solar cell module at a low cost.

  Further, since the pressure is applied with a roller while the sealing resin is in a molten state, the uniformity of the thickness of the sealing resin can be increased. Further, the thickness of the sealing resin can be controlled by adjusting the gap between the pressure roller and the solar cell element.

  Before the sealing step, a heat-sealed sealing resin is supplied onto the front surface material or the back surface material, and the sealing resin is pressurized with a roller while the sealing resin is in a molten state. By having a step of placing the solar cell element on the sealing resin, the following effects are obtained. That is, a sealing resin with little thickness unevenness and excellent flatness can be formed on the front surface material or the back surface material, and when the solar cell element is placed on the sealing resin, the sealing resin Bubbles are less likely to accumulate between the solar cell elements.

  When the surface material is a glass substrate having a high surface flatness, the thickness uniformity of the sealing resin can be increased. This further prevents air bubbles from remaining in the solar cell module. When the surface material is a weather-resistant resin film, the surface material can be supplied by a roll, which makes it possible to continuously produce a long solar cell module.

  When the sealing step is a step of sealing both surfaces of the solar cell element, both surfaces of the sealed solar cell element can be finished in a flat state. Thereby, even when the sealed solar cell element is bonded to a rigid substrate such as a glass substrate in the subsequent process, the flatness of the bonding surface of the substrate and the bonding surface of the sealing resin can be ensured. In addition, there is an effect that a solar cell module having excellent appearance and reliability can be produced without remaining bubbles. Further, the present invention can be applied to a solar cell module having a structure in which a sealing resin is arranged on both surfaces of a solar cell element and the solar cell element is sealed, which is the most common among conventional solar cell modules. Therefore, it can be said that the solar battery cell which can be used for sealing is a highly versatile manufacturing method in that it is not particularly limited.

  After the sealing step, the sealed solar cell element is placed on the heated surface material or back surface material, and having a step of pressing with a roller while the sealing resin is in a molten state, Adhesion to a glass substrate as a translucent member can also be performed continuously. Therefore, the productivity of the solar cell module is further improved.

  When the viscosity of the sealing resin during roller pressurization is 100,000 mPa · s to 10 million mPa · s, the fluidity of the resin is moderate, and it can be extruded from the extruder to some extent without sagging. it can.

  By supplying the sealing resin with an extruder, high-throughput production with simple equipment becomes possible.

  By having the process of heating the whole solar cell module after the said sealing process, the adhesiveness of sealing resin and each member further improves, and a more reliable solar cell module can be manufactured. .

  By having the step of heating the solar cell element before the sealing step, the followability of the sealing resin to the irregularities on the surface of the solar cell element is further improved, and the solar cell element and the sealing resin Adhesiveness is improved. Therefore, it becomes possible to manufacture a highly reliable solar cell module while more reliably suppressing the gaps and bubbles remaining between them.

  When the sealing resin is a thermoplastic resin, when the sealing resin is heated and melted, the temperature can be raised to a high temperature of 150 ° C. or higher, thereby reducing the viscosity of the sealing resin and supplying it. Therefore, the variable range of the thickness of the sealing resin can be expanded. In addition, since the sealing resin is a thermoplastic resin, a cross-linking step of the sealing resin is not required, so that the production throughput is increased.

  One embodiment of the present invention will be described with reference to FIG.

  In FIG. 1, 1 is a surface material, 2 is a solar cell element, 3 is a first sealing resin, 4 is a second sealing resin, 5 and 6 are resin pellets, 7 is an extruder, and 8 is T A die such as a die, 9 is a first pressure roller, and 10 is a second pressure roller.

  As shown in FIG. 1, first, the first sealing resin pellet 5 is heated and melted in an extruder 7, and the first sealing resin 3 is supplied onto the surface material 1 from a die 8. Since the surface material 1 is conveyed at a constant speed from the left direction to the right direction by the first pressure roller 9 and the second pressure roller 10, a certain amount of sealing is applied on the surface material 1. Resin is supplied uniformly. The supplied first sealing resin 3 is pressurized by the first pressure roller 9 while in the molten state. This prevents bubbles from accumulating between the surface material 1 and the first sealing resin 3.

  After that, while the first sealing resin 3 is in a molten state, the solar cell element 2 is placed on the first sealing resin 3. Next, the second sealing resin pellet 6 is heated and melted in the extruder 7, and the second sealing resin 4 is supplied from the die 8 onto the solar cell element 2.

  The solar cell element 2 is preferably heated in advance, and the temperature is preferably equal to or higher than the extrusion temperature of the sealing resins 3 and 4 from the die 8. In this way, both when the solar cell element 2 is placed on the first sealing resin 3 and when the second sealing resin 4 is supplied onto the solar cell element 2, the sealing is performed. The temperature of the stop resins 3 and 4 does not drop rapidly. Therefore, sufficient adhesiveness expression at the interface between the sealing resins 3 and 4 and the solar cell element 2 can be expected. The solar cell element 2 may be heated by selecting various conventionally known methods such as hot air and infrared heater.

  Next, the supplied second sealing resin 4 and the first sealing resin 3 are pressurized by the second pressure roller 10 while in the molten state. This prevents bubbles from accumulating between the solar cell element 2 and the second sealing resin 4. Furthermore, since the air bubbles remaining when the solar cell element 2 is placed on the first sealing resin 3 can be pushed out by the second pressure roller 10, the surface material 1 and the second sealing material are sealed. Defoaming between the stopping resins 4 can also be performed satisfactorily.

  Here, the molten state means that the average temperature of the sealing resin is equal to or higher than the melting point. Specifically, the viscosity of the sealing resin is 10 million mPa · s or less, preferably 100,000. ~ 10 million mPa · s, more preferably 500,000 to 5 million mPa · s. If it exceeds 10 million mPa · s, the fluidity of the resin is too small, the followability to the unevenness on the surface of the element becomes insufficient, voids and bubbles remain easily, and the adhesion between the resin and the element Tends to be insufficient. On the other hand, if it is less than 100,000 mPa · s, the fluidity of the resin is too high, so that the resin thickness sufficient to fill the unevenness of the solar cell element cannot be maintained.

  In order for the sealing resin to be supplied to the pressure roller in a sufficiently molten state, the extrusion temperature of the sealing resin from the die is set to a temperature about 50 to 80 ° C. higher than the melting point of the sealing resin. It is preferable.

  The thickness of the sealing resin after being pressurized with a pressure roller is preferably 100 to 1,000 μm, and more preferably 200 to 800 μm. If the thickness is less than 100 μm, it is difficult to maintain the sheet shape, and if it exceeds 1,000 μm, the extrusion amount of the resin per unit time increases, and sufficient throughput cannot be obtained. The thickness of the sealing resin can be adjusted by adjusting the gap between the pressure rollers.

  In FIG. 1, the pressure roller is provided on both sides of the surface material on which the sealing resin is supplied and on the non-supplied side, but the pressure roller is at least on the side on which the sealing resin is supplied. If it is in. In this case, the surface material may be conveyed by a conveyor or the like.

  The solar cell module thus obtained is preferably heated as a whole. By heating the entire solar cell module, the adhesion between the sealing resin and the solar cell element and / or the surface material can be made more reliable, so that the reliability of the solar cell module can be further increased. it can. As a heating method, there are a method of continuously heating with a conveyor oven, a method of heating with a sheet using an oven, and the like. Among these, heating by a conveyor oven using hot air, an infrared heater or the like is preferable in order to be suitable for improving throughput by continuous production, which is one of the objects of the present invention.

  Since the solar cell module manufacturing method of the present invention is manufactured by melting inexpensive resin pellets and supplying at least one side of the solar cell element, the manufacturing cost is low. Further, since no bubbles remain in the solar cell module, a highly reliable solar cell module can be manufactured.

  Next, another embodiment of the present invention will be described with reference to FIG.

  In FIG. 6, 2 is a solar cell element, 61 is a pressure roller, 62 is a front surface sealing resin, 63 is a back surface sealing resin, 64 is a hopper, 7 is an extruder, and 8 is a die.

  In this example, sealing resin is simultaneously supplied to both surfaces of the solar cell element 2. The sealing resin is charged as a pellet raw material from the hopper 64, melted by the extruder 7, and extruded in a molten state from a slit provided in a die 8 such as a T die. The extruded surface sealing resin 62 and the back surface sealing resin 63 are supplied to the front surface and the back surface side of the solar cell element 2 and are pressurized by the pressure roller 61 while in the molten state.

  Next, as shown in FIG. 7, the sealed solar cell element (solar cell element sealing body 73) is placed on a surface material 72 such as a glass substrate previously heated by a heater or the like, and sealed. While the resin is in a molten state, the pressure roller 71 applies pressure from the end. By carrying out like this, it becomes possible to manufacture consistently the solar cell module using a glass substrate as a translucent member of the surface.

  By performing the pressurization with a roller, the surface of the solar cell element sealing body is finished flat, and when the sealing body and the front surface material or the back surface material are bonded together, residual bubbles can be suppressed. In addition, if a roller is used, a resin melt wider than the solar cell element can be pressure-bonded, and a solar cell sealing body in a state where the solar cell element is completely embedded in the resin can be easily produced. Can do.

  Hereinafter, the member used by this invention is demonstrated in detail.

<Solar cell element>
For the solar cell element, conventionally known elements such as crystalline silicon, polycrystalline silicon, microcrystalline silicon, amorphous silicon, copper indium selenide, compound semiconductor, and the like may be variously selected according to the purpose. These solar cell elements may be used alone, but can be used in the production process of the present invention in a state where a plurality of solar cell elements are connected in series or in parallel according to a desired voltage or current. Alternatively, a solar cell element obtained by integrating a solar cell element on an insulated substrate to obtain a desired voltage or current can be used.

  The surface of the solar cell element is usually provided with electrode members such as a comb-shaped collector electrode for collecting generated power to the outside and a bus bar electrode for collecting the power from the collector electrode. Further, in order to prevent reverse bias application to the element, a bypass diode is mounted on the element as necessary.

<Surface material>
The surface material is not particularly limited, but glass, a transparent resin film, a transparent resin plate, and the like are preferable. Generally, glass is used from the viewpoint of impact resistance, transparency, and the like. In the present invention, it is particularly preferable to use glass as a material excellent in strength and flatness because it is pressed by a pressure roller.

<Resin for sealing>
The sealing resin is used to fill the unevenness of the solar cell element and protect the element from the external environment. Therefore, there is no particular limitation as long as the resin satisfies the performance required as a filler for the solar cell module, melts by heating, and can be extruded by an extruder. Here, the performance required as a filler for the solar cell module is, for example, transparency, weather resistance, heat resistance, adhesion to the module constituent material, and the like. However, when the sealing resin is used on the non-light-receiving surface side, transparency is not required.

  Materials satisfying such requirements include ethylene-vinyl acetate copolymer (EVA) resin, ethylene-methyl acrylate copolymer (EMA) resin, ethylene-ethyl acrylate copolymer (EEA) resin, ethylene- Examples thereof include thermoplastic resins such as acrylic acid copolymer (EAA) resin, ethylene-methacrylic acid copolymer (EMAA) resin, ionomer resin, and polyvinyl butyral resin. In addition, an ethylene-unsaturated fatty acid ester-unsaturated fatty acid terpolymer can be used. Among them, EAA resin, EMAA resin, ionomer resin, especially EMAA resin, can be balanced for solar cell applications such as weather resistance, adhesiveness, heat resistance, cold resistance, and impact resistance without crosslinking with organic peroxides. It has excellent physical properties. Therefore, these resins are preferably used in the production method of the present invention.

  It is preferable to add an additive to the sealing resin on the light-receiving surface side for the purpose of improving weather resistance, adhesiveness, heat resistance and the like. Specifically, ultraviolet absorbers and light stabilizers are used to improve weather resistance, antioxidants are used to improve heat resistance, and silane coupling agents and titanium couplings are used to improve adhesion. Add agent. The compounding method can extrude the thermoplastic resin in which the additive is dispersed if a mixture of the sealing resin pellets and the additive is mixed in advance into the hopper of the extruder.

  The sealing resin on the non-light-receiving surface side is necessary for filling the unevenness on the back surface of the solar cell element and protecting the element from the external environment. Moreover, when providing a back surface material in a solar cell element back surface, it also plays the role which adhere | attaches a back surface material to a solar cell element. Therefore, since weather resistance, adhesiveness, and heat resistance are required in the same manner as the sealing resin on the light receiving surface side, a material suitable as the sealing resin on the light receiving surface side is used as the sealing resin on the non-light receiving surface side. Are also preferably used. Usually, the same material as the sealing resin on the light receiving surface side is used for the sealing resin on the non-light receiving surface side. Further, like the sealing resin on the light receiving surface side, additives such as an ultraviolet absorber, a light stabilizer, and an antioxidant are usually blended. Further, since transparency is not essential, it is possible to add a filler such as an inorganic oxide together with an additive to improve the weather resistance and mechanical strength, and it may be colored with a pigment or the like.

<Pressure roller>
The pressure roller is preferably provided with a drive mechanism and is rotated, so that the pressure roller can also carry the solar cell element and the like. Further, the sealing resin in a molten state is pressed against the solar cell element with a very uniform thickness without accumulating in the pressure roller insertion portion. Furthermore, the thickness of the sealing resin can be adjusted by changing the rotation speed.

  The structure and material of the pressure roller are not particularly limited, but the structure and material are excellent in releasability from the sealing resin and can press the sealing resin uniformly following the unevenness of the surface of the solar cell element. Desirably, a specific example is a roller made of silicone rubber having a structure that keeps the pressing force constant while changing the gap between the two pressure rollers with a spring or the like.

<Extruder>
Although the structure of the extruder is not particularly limited, it is common to extrude the sealing resin heated and melted by a pump, and various types are selected from a gear pump type, a screw pump type, etc. according to the melt viscosity of the resin. be able to. Since a sealing resin used for sealing a solar cell element usually has a high melt viscosity and a large amount of extrusion per unit time, it is desirable to use a screw pump type extruder.

  Hereinafter, the manufacturing method of the solar cell module of this invention is demonstrated in detail based on a specific Example. In addition, this invention is not limited to a following example at all, and can be variously changed within the range of the summary.

<Example 1>
In FIG. 1, the outline of the manufacturing method of the solar cell module of a present Example was shown.

  As the solar cell element 2, a series of 6 solar cell cells of approximately 150 mm square are serially arranged in 4 rows to form a solar cell string in which a total of 24 solar cells of 6 × 4 are serialized. did. The cells are serialized by an interconnector made of a copper tab, and a polyester tape that is easily peeled is attached to the electrode lead-out portion in advance. The polycrystalline silicon solar cell used here has a thickness of about 250 μm and a comb-shaped current collecting electrode having a height of about 50 μm. In the solar cell string, since the thickness of the copper tab used for serialization is added to the collecting electrode, the surface is formed with unevenness of about 200 μm at the maximum. Further, when pressurizing the sealing resin, a resin tape having a higher melting point than that of the sealing resin (for example, a polyester tape) in order to prevent the neighboring cells from coming into contact with each other when the solar battery cells are displaced. The cells adjacent to each other are fixed.

  First, an ethylene-methacrylic acid copolymer (EMAA) resin (melting point: 92 ° C.) pellets 5 were put into an extruder 7 and heated and melted at about 160 ° C., and then attached to the tip of the extruder 7 with an effective width of 800 mm. From the slit of the die 8, it was dropped to the end of the first pressure roller 9. Here, the first pressure roller 9 is provided with a driving device, whereby the glass substrate as the surface material 1 can be sent out from the left to the right. Therefore, the first sealing resin 3 in the molten state dropped at the end of the first pressure roller 9 is rotated on the surface material 1 while the first pressure roller 9 is rotated. To be supplied. The melt viscosity of the first sealing resin 3 immediately before being extruded from the die 8 and dropped onto the first pressure roller 9 is about 1 million mPa · s, and is still in a completely melted state. Therefore, by applying pressure with the first pressure roller 9, the air is not accumulated between the first sealing resin 3 and the surface material 1, and the flatness is high and the resin thickness is excellent in uniformity of about 500 μm. A thick first sealing resin 3 could be supplied onto the surface material 1.

  Next, the solar cell element 2 was placed on the first sealing resin 3 supplied on the surface material 1. At this time, the solar cell element 2 was conveyed to the second pressure roller 10 while being heated to 180 ° C. by an infrared heater (not shown). The melt viscosity of the first sealing resin 3 at this time is about 1.2 million mPa · s, and is still in a completely molten state.

  Next, in the same manner as when the first sealing resin 3 was extruded and supplied, the EMAA resin as the second sealing resin 4 was supplied onto the solar cell string. First, the pellet 6 of EMAA resin (melting point: 92 ° C.) was put into the right extruder 7, heated and melted at about 160 ° C., and then passed through the slit of the die 8 having an effective width of 800 mm attached to the tip of the extruder 7. 2 was dropped at the end of the pressure roller 10. Here, the driving device is attached to the second pressure roller 10, whereby the surface material 1 can be sent out from the left to the right. Accordingly, the second sealing resin 4 in a molten state dropped at the end of the second pressure roller 10 is solar cell element 2 while being pressurized by the rotation of the second pressure roller 10. Supplied on top. The melt viscosity of the second sealing resin 4 immediately before being extruded from the die 8 and dropped onto the second pressure roller 10 is about 1 million mPa · s, and is still in a completely melted state. Therefore, by transporting while being pressurized with the second pressure roller 10, the flatness is high and the resin thickness is uniform without accumulating bubbles between the second sealing resin 4 and the solar cell element 2. The excellent second sealing resin 4 having a thickness of about 500 μm could be supplied onto the solar electronic element 2. Further, the melt viscosity of the first sealing resin 3 immediately before being pressed by the second pressure roller 10 is about 1.5 million mPa · s, and is still in a completely molten state. For this reason, the solar cell element 2 can be sealed without accumulating bubbles between the first sealing resin 3 and the solar cell element 2 by being conveyed while being pressurized by the second pressure roller 10. It was.

<Example 2>
In FIG. 2, the outline of the manufacturing method of the solar cell module of a present Example was shown. The parts where the reference numerals are omitted have the same configuration as in FIG.

  When the solar cell element 2 is placed on the first sealing resin 3, the third pressure roller 21 is used, and when the solar cell element 2 is passed between the third pressure rollers 21, between the strings Inserted while bending. Other than that was carried out similarly to Example 1, and created the solar cell module.

  In this embodiment, each cell of the solar cell element 2 is not in contact with the first sealing resin 3 until it is pressurized by the third pressure roller 21, and is in a row of cells when pressurized. Only the first sealing resin 3 and the third pressure roller 21 are pressurized and bonded to the first sealing resin 3. Since the solar cell element 2 is sequentially adhered onto the first sealing resin 3 in this manner, the defoaming property between the solar cell element 2 and the first sealing resin 3 can be further improved. Furthermore, it is possible to provide a solar cell module excellent in appearance and reliability.

<Example 3>
In FIG. 3, the outline of the manufacturing method of the solar cell module of a present Example was shown. The parts where the reference numerals are omitted are the same as those in FIG.

  As the solar cell element 2, a bendable solar cell string 31 was used. Other than that was carried out similarly to Example 2, and created the solar cell module.

  The bendable solar cell string 31 is a series of four rows of six bendable solar cells in which amorphous silicon of about 1 mm thickness is formed on a 0.15 mm thick bendable stainless steel substrate. And a total of 24 solar cells of 6 × 4 are serialized.

  The bendable solar cell string 31 is excellent in bendability and can be wound around a roll having a radius of 300 mm. Therefore, when the first sealing resin 3 and the bendable solar cell string 31 are pressed by the third pressure roller 21, the bendable solar cell string 31 can be bent and supplied in a curved shape. The defoaming property can be further improved.

<Example 4>
In FIG. 4, the outline of the manufacturing method of the solar cell module of a present Example was shown. The portion where the reference numerals are omitted has the same configuration as in FIG.

  Instead of the surface material, a 0.2 mm thick coated galvalume steel plate unwound from the roll was used as the back surface material 41. Furthermore, after pressurizing the second sealing resin 4 with the second pressure roller 10, the surface material 42 unrolled from the roll while the second sealing resin 4 is in a molten state ( A 50 μm-thick fluororesin film) was pressed and adhered by the fourth pressure roller 43. Other than that was carried out similarly to Example 3, and created the solar cell module.

  By doing in this way, the bendable solar cell module excellent in the external appearance and reliability can be continuously produced.

<Example 5>
In FIG. 5, the outline of the manufacturing method of the solar cell module of a present Example was shown. The parts where the reference numerals are omitted have the same configuration as in FIG.

  A roll-shaped solar battery cell 51 was used as the solar battery element. Other than that was carried out similarly to Example 4, and created the solar cell module. The roll-shaped solar battery cell 51 is obtained by forming an amorphous silicon solar battery having a thickness of about 0.4 μm on a roll-shaped stainless steel substrate having a thickness of 0.15 mm by a roll-to-roll method.

  As shown in the present embodiment, by using the roll-shaped solar battery cells, all members constituting the solar battery module can be continuously supplied, and the solar battery module can be continuously manufactured. .

<Example 6>
In FIG. 6, the outline of the manufacturing method of the solar cell module of a present Example was shown.

  A pellet of EMAA resin (melting point: 92 ° C.) in which a benzophenone ultraviolet absorber, a hindered amine light stabilizer, and a hindered phenol antioxidant are mixed as additives in a hopper 64 of a single screw extruder 7 having a screw diameter of 30 mm. throw into. And resin is extruded from the slit of T die (die 8) of effective width 800mm attached to the front-end | tip of the extruder 7. FIG. The temperature of the resin extruded from the die 8 is 160 ° C.

  First, the surface sealing resin 62 is inserted between two pressure rollers 61 whose surfaces slightly below the slits of the die 8 are covered with silicon rubber. For the insertion, the surface sealing resin 62 first extruded from the die 8 is once placed on the end of the inserted film between the pressure rollers 61, and the surface sealing resin 62 extruded together with the film is applied to the pressure roller 61. This is done by inserting in between and then removing the film. The two pressure rollers 61 are provided with a spring mechanism so that a material inserted between the rollers can be pressed with a constant pressure, and also provided with a drive mechanism by a motor with a variable rotation speed.

  Similarly to the front surface sealing resin 62, the back surface sealing resin 63 is also inserted between the pressure rollers 61 slightly above the slits of the die 8.

  Thus, between the pressure rollers 61, the sealing resin in a molten state is supplied from above and below. The melt viscosity of the front surface sealing resin 62 and the rear surface sealing resin 63 immediately before the pressure roller 61 is about 1 million mPa · s and the thickness is 400 μm.

  Next, as the solar cell element 2, the same solar cell string as in Example 1 is heated to 180 ° C. with an infrared heater while being conveyed by a conveyor, and the sealing resin extruded on the front and back surfaces is arranged. Between the pressure rollers 61. Then, the sealing resin is pressure-bonded to both sides of the solar cell string by the pressure roller 61. The conveyance speed of the solar cell string at this time is 1.5 m / min.

  Next, as shown in FIG. 7, the sealed solar cell element (solar cell element sealing body 73) is angled on a 3.2 mm white tempered glass (surface material 72) heated to 180 ° C. To be placed. And the surface material 72 and the solar cell element sealing body 73 are inserted between the pressure rollers 71, and the solar cell element sealing body 73 is pressure-bonded to the surface material 72 from the end portion.

  Thereafter, the substrate is heat treated at 180 ° C. for 20 minutes and then cooled. Lastly, the sealing resin on the polyester tape previously attached to the electrode take-out part is removed together with the polyester tape, the lead wire is soldered, and the electrode exposed part of the soldered part is sealed with silicone resin to Complete the battery module.

Observation of the appearance of the solar cell module produced in this manner revealed no problems with no residual bubbles or voids in the sealing material. A. M.M. When the electrical output was measured under simulated sunlight of −1.5 and 100 mW / cm ² , it was confirmed that an output equivalent to that of a solar cell module produced using a conventional vacuum laminator was obtained. Furthermore, in order to confirm the reliability of the produced solar cell module, the following high temperature and high humidity test, temperature and humidity cycle test, and temperature cycle test were performed.

(1) High-temperature and high-humidity test It is put in an atmosphere of 85 ° C./85% RH for 1000 hours.

(2) Temperature / humidity cycle test 10 cycles of a temperature / humidity cycle of −40 ° C./30 minutes and 85 ° C./85% RH / 20 hours are performed.

(3) Temperature cycle test 200 cycles of a temperature cycle of −40 ° C./30 minutes and 90 ° C./4 hours are performed.

  As a result of each test, no change was observed in the appearance and electrical characteristics of the solar cell module in any test, and the solar cell module according to this production method has excellent long-term reliability under outdoor use conditions. It was confirmed that

<Example 7>
In FIG. 8, the outline of the manufacturing method of the solar cell module of a present Example was shown. In this example, in Example 6, the sealing resin is extruded downward from the die of the extruder.

  The sealing resin extruded from the dies 8 of the two extruders 7 is pressure-bonded to the solar cell element 2 by the pressure roller 61 provided below the dies 8, and the solar cell element sealing body is manufactured. . Then, the solar cell element sealing body is pressure-bonded by a roll onto a glass substrate placed horizontally while being bent. In this example, a thin-film silicon solar cell element formed on a 155 mm square stainless steel substrate is used as the solar cell element. Since the solar cell element is flexible, the sealed solar cell element is bent. There is no problem.

  Except for the above, a solar cell module produced in the same manner as in Example 6 was evaluated. As a result, there was no problem in both electrical output and reliability, and it was confirmed that the solar cell module had the same performance as the solar cell module in Example 6. It was done.

It is the figure which showed an example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the other example of the manufacturing method of this invention. It is the figure which showed the structural material of the conventional solar cell module. It is the figure which showed the structure of the conventional solar cell module. It is the figure which showed the other structure of the conventional solar cell module.

Explanation of symbols

1: Surface material 2: Solar cell element 3: First sealing resin 4: Second sealing resin 5, 6: Resin pellet 7: Extruder 8: Die 9: First pressure roller 10: 2nd pressure roller 21: 3rd pressure roller 31: bendable solar cell string 41: back surface material 42: surface material 43: 4th pressure roller 51: roll-shaped solar cell 61: pressure Roller 62: Resin for surface sealing 63: Resin for rear surface sealing 64: Hopper 71: Pressure roller 72: Surface material 73: Solar cell element sealing body 91: Glass substrate 92, 93: Sheet-like filler 94: Sun Battery element 95: Back surface sheet 96: Filler 100: Super straight structure solar cell module 110: Substrate structure solar cell module 111: Surface film 112: Solar cell element 113: Back surface steel plate 114: Filler

Claims (12)

  It has a sealing step of supplying a sealing resin heated and melted to at least one surface of the solar cell element, and pressurizing the sealing resin with a roller while the sealing resin is in a molten state. A method for manufacturing a solar cell module.   Before the sealing step, a heat-sealed sealing resin is supplied onto the front surface material or the back surface material, and the sealing resin is pressurized with a roller while the sealing resin is in a molten state. The method for producing a solar cell module according to claim 1, further comprising a step of placing a solar cell element on the sealing resin.   The said surface material is a glass substrate or a weather-resistant resin film, The manufacturing method of the solar cell module of Claim 2 characterized by the above-mentioned.   The method for manufacturing a solar cell module according to claim 1, wherein the sealing step is a step of sealing both surfaces of the solar cell element.   After the sealing step, the sealed solar cell element is placed on a heated surface material or back surface material, and has a step of pressing with a roller while the sealing resin is in a molten state. The manufacturing method of the solar cell module of Claim 4.   The said surface material is a glass substrate or a weather-resistant resin film, The manufacturing method of the solar cell module of Claim 2 characterized by the above-mentioned.   The method for producing a solar cell module according to any one of claims 1 to 6, wherein the viscosity of the sealing resin during roller pressurization is 100,000 mPa · s to 10 million mPa · s.   The method for manufacturing a solar cell module according to claim 1, wherein the sealing resin is supplied by an extruder.   The method for manufacturing a solar cell module according to claim 1, further comprising a step of heating the entire solar cell module after the sealing step.   The method for manufacturing a solar cell module according to claim 1, further comprising a step of heating the solar cell element before the sealing step.   The method for manufacturing a solar cell module according to claim 1, wherein the sealing resin is a thermoplastic resin.   The method for producing a solar cell module according to claim 11, wherein the thermoplastic resin contains an ethylene-methacrylic acid copolymer as a main component.

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