JP2010278147A - Manufacturing method of solar cell module - Google Patents

Abstract

A method of manufacturing a solar cell module having excellent design properties and power generation efficiency is provided.
In a method of manufacturing a solar cell module in which a solar cell element is sealed between a substrate and a protective material via a filler, a first step of raising the filler to a melting point temperature or higher, and the first step A second step of pressing between the substrate and the protective material at a pressure higher than the step; a third step of pressing between the substrate and the protective material at a pressure higher than the second step; And a fourth step of monotonically reducing the maximum pressure of the third step.
[Selection] Figure 1

Description

  The present invention relates to a method for manufacturing a solar cell module.

  In general, a solar cell module has a laminated structure in the order of a translucent substrate, a light receiving surface side filler, a plurality of solar cell elements electrically connected to each other by a conducting wire, a back surface side filler, and a back surface protective material. To do. In the laminating process in the manufacturing process of the solar cell module, the laminated body (module laminated body) of the constituent members is bonded and integrated by pressing while heating.

  Conventionally, in the laminating process, the module laminate is placed on the laminator heater panel, the housing is closed and decompressed, and then the module laminate is heated by pressing the module laminate and heating the module laminate. It was done.

  However, the conventional laminating process has a problem that the filler flows out from the peripheral portion of the solar cell module during pressurization, and the thickness of the filler at the peripheral portion tends to be thin.

  Therefore, for the purpose of producing a solar cell module having a sufficient thickness for the filler at the peripheral edge, a method for producing a solar cell module in which a module laminate is heated and pressurized in a frame body is disclosed (for example, Patent Document 1). ).

  Furthermore, in order to prevent the solar cell element from cracking in the laminating process, a method for manufacturing a solar cell module in which the module laminate is pressed at a low pressure for a long time is disclosed. (For example, Patent Document 2)

JP 2000-31519 A JP 2008-294486 A

  However, in the manufacturing method of the solar cell module described in Patent Document 1, the maximum pressing force is applied by the first pressing after the temperature rise, and the time occupies about half of the laminating process. As shown in FIG. 5, the colored back side filler fills the light receiving surface side of the solar cell element, making the appearance of the solar cell element uneven, and blocking incident light on the light receiving surface side of the solar cell element, There has been a problem that the appearance and power generation efficiency are reduced.

  Moreover, in the manufacturing method of the solar cell module described in Patent Document 2, priority is given to prevention of cracking of the solar cell element, and the laminating process is pressed at a low pressure for a long time, so that productivity is low and suitable for actual manufacturing. There was no problem.

  The present invention has been made in view of the above-described problems, and an object thereof is to provide a method for manufacturing a solar cell module excellent in appearance and power generation efficiency.

  The method for manufacturing a solar cell module according to the present invention is a method for manufacturing a solar cell module in which a solar cell element is sealed via a filler between a substrate and a protective material. A laminating step of laminating a solar cell element, a back surface side filler, and a back surface side protective material in this order to form a module laminate, a first step of raising the filler above the melting point temperature, From the second step of pressing the module laminate at a higher pressure than the first step, the third step of pressing the module laminate at a higher pressure than the second step, and the maximum pressure of the third step And a pressing step including a fourth step of monotonically reducing pressure.

  Furthermore, the temperature of the filler is monotonously increased from the first step to the third step.

  Furthermore, the time required for the third step is 15% to 50% of the time required for the second step.

  Further, the pressure in the third step is 250% to 350% of the pressure in the second step.

  Furthermore, after the said 4th process, the 5th process of pressing the said module laminated body by the pressure higher than the said 1st process and lower than the said 2nd process is characterized by the above-mentioned.

  According to the method for manufacturing a solar cell module of the present invention, in the method for manufacturing a solar cell module in which a solar cell element is sealed via a filler between the substrate and the protective material, the translucent substrate and the light receiving surface side A laminating step of laminating a filler, a solar cell element, a back side filler, and a back side protective material in this order to form a module laminate; and a first step of raising the filler to a melting point temperature or higher. A second step of pressing the module laminate at a higher pressure than the first step, a third step of pressing the module laminate at a higher pressure than the second step, and a maximum of the third step By having a pressing step including a fourth step that monotonously depressurizes from the pressure, it is possible to suppress the time for pressing at a high pressure when the filler is melted. Necessity of materials It is possible to suppress the above, such flow, the light-receiving surface of the solar cell element can be reduced wraparound back side filler, it is possible to manufacture a solar cell module having excellent appearance and power generation efficiency. This is because, after the temperature of the filler exceeds the melting point temperature in the first step, a lower pressing force than the third step is previously applied in the second step, and a higher pressing force than the second step is applied in the third step. This is because it is added in a shorter time than the second step. And since the time which applies high pressing force as a whole can be shortened, the load to a solar cell element can be reduced.

  Furthermore, according to the method for manufacturing a solar cell module of the present invention, the temperature of the filler is monotonously increased from the first step to the third step, whereby the back surface toward the light receiving surface side of the solar cell element. A solar cell module having a good appearance without side wraparound can be manufactured with a short tact time. This is efficient because the pressing force suitable for the change in fluidity of the filler at the temperature of each step can be applied by adjusting the pressing force of each step while increasing the temperature of the filler. This is because the solar cell module can be filled with a filler.

It is a sectional side view which shows the lamination process which manufactures the solar cell module of this invention, (a) is a sectional side view which shows the mode of a 1st process, (b) is a 2nd process, a 4th process, and a 5th process. It is a sectional side view which shows the mode of a process, (c) is a sectional side view which shows the mode of a 3rd process. BRIEF DESCRIPTION OF THE DRAWINGS It is a perspective view which shows the lamination | stacking state of the solar cell module which concerns on this invention, (a) is a perspective view which shows the solar cell matrix formed by connecting several solar cell elements with a connection conductor, (b) is a translucent board | substrate. FIG. 3 is an exploded perspective view illustrating a laminated state of a module laminate including a light receiving surface side filler, a solar cell element matrix, a back surface side filler, and a back sheet. It is a schematic diagram which shows the solar cell module manufactured by this invention, (a) is the top view seen from the light-receiving surface side, (b) is the sectional side view which looked at (a) from the AA 'cross section. It is. It is a figure which shows temperature and a pressure in the lamination process of the manufacturing method of the solar cell module of this invention. It is a schematic diagram which shows the solar cell module manufactured by the prior art, (a) shows a top view, (b) shows the sectional side view which looked at (a) from the B-B 'cross section. It is the photograph which compares the external appearance of a solar cell module, (a) shows a prior art, (b) shows one Embodiment of this invention.

  One embodiment of a method for producing a solar cell module according to the present invention is a method for producing a solar cell module in which a solar cell element is sealed between a substrate and a protective material via a filler. A laminating step of laminating a surface-side filler, a solar cell element, a back-side filler, and a back-side protective material in this order to form a module laminate, and a first that raises the filler above the melting point temperature A step, a second step of pressing the module laminate at a higher pressure than the first step, a third step of pressing the module laminate at a higher pressure than the second step, and the third step And a pressing step including a fourth step in which the pressure is monotonously reduced from the maximum pressure.

  In a method for manufacturing a solar cell module in which a solar cell element is sealed via a filler between a substrate and a protective material, a first step of raising the filler to a melting point temperature or higher, and higher than the first step A second step of pressing between the substrate and the protective material with pressure, a third step of pressing between the substrate and the protective material with a higher pressure than the second step, and the third step And a fourth step of monotonically reducing the maximum pressure. This is, for example, as shown in the relationship between temperature, pressure and time in FIG.

  Furthermore, the temperature of the filler is monotonously increased from the first step to the third step. This is, for example, as shown in the relationship between temperature and time in FIG.

  Furthermore, in one embodiment of the method for manufacturing a solar cell module of the present invention, the time required for the third step is 15% to 50% of the time required for the second step. This is, for example, as shown in the time relationship between the second step and the third step in FIG.

  Furthermore, in one embodiment of the method for producing a solar cell module of the present invention, the pressure in the third step is 250% to 350% of the pressure in the second step. This is, for example, as shown in the relationship between the pressure in the second step and the third step in FIG.

  Furthermore, in one embodiment of the method for manufacturing a solar cell module of the present invention, after the fourth step, a fifth step of pressing the module laminate at a pressure higher than the first step and lower than the second step. Is included. This is, for example, as shown in the relationship between temperature, pressure and time in FIG.

  Below, the manufacturing method of the solar cell module of this invention is demonstrated, referring drawings for every process.

(First step)
FIG. 1 shows a side sectional view of a laminator 1 in the first step. A module laminate 20 is placed in the laminator 1. As shown in FIG. 2, the module laminate 20 includes a translucent substrate 21, a light receiving surface side filler 22a, a matrix 23 in which solar cell elements 25 are electrically integrated by conductors 26, and a back surface side filler. 22b and the back surface protective material 24 are comprised in this order. In particular, the back surface side filler 22b may be colored from the viewpoint of enhancing the appearance and power generation efficiency.

  First, as shown in FIG. 1A, the module laminate 20 is placed on the heating plate 8 in the lower housing 3 of the laminator 1 so that the translucent substrate 21 faces down. At this time, the heating plate 8 may be about 170 ° C., for example. Then, the upper housing 2 is lowered to the lower housing 3 side to close the housing.

  Then, the module laminate 20 is heated to the melting point temperature or higher of the filler 22 while reducing the pressure in the upper vacuum region 5 and the lower vacuum region 6. For example, when EVA (ethylene / vinyl acetate copolymer resin) is used for the filler 22, the melting point is about 60 ° C. to 75 ° C. Therefore, the module laminate 20 is preferably heated to 75 ° C. to 85 ° C. so that the temperature of the entire filler 22 is equal to or higher than the melting point temperature.

  In addition, the translucent board | substrate 21 in a present Example points out the board | substrate in a claim, For example, a white board tempered glass, an acrylic board, etc. can be used. Moreover, the back surface protective material 24 points out a protective material, for example, can use the PET resin sheet, the PEN resin sheet, or what laminated | stacked it.

(Second step)
Next, when the decompression of the upper vacuum region 5 is stopped and the pressure is increased and held, a pressure difference is generated between the upper vacuum region 5 and the vacuum region 6 as shown in FIG. It expands and presses the module laminate 20. In addition, heating of the module laminated body 20 is continued also during a 2nd process.

  By applying the pressing force in this way, the molten filler 22 can be poured into a macro shape such as a gap or unevenness of the matrix 23. Further, since the module laminate 20 is preheated and softened to the melting point temperature of the filler 22 in the first step, damage to the solar cell element due to the pressing force can be suppressed.

  The pressing force in the second step is lower than the pressing force in the third step, which will be described later, and is specifically preferably 15 kPa to 25 kPa. The diaphragm sheet 4 is sequentially contacted from the center to the end of the module laminate 20 and applied with a low pressing force, so that the diaphragm sheet 4 is filled with the filler 22 in order from the macro gap near the center of the module laminate 20. Therefore, there is no such thing as the peripheral part is filled first and the bubble degassing path is blocked as in the case of pressing with a large pressing force at the beginning, and it is possible to prevent the bubble from remaining. it can.

  The holding time of the pressing force in the second step should be a relatively long time so that the space between the solar cell elements 25 and the unevenness are filled with the light receiving surface side filler 22a and the back surface side filler 22b. However, if the time is too long, the temperature rise continues, so that the fluidity of the filler 22 becomes too high, and the filler 22 wraps around the light receiving surface side of the solar cell element 25, or the module laminate. It will stick out around 20. For this reason, it is preferable that the holding time of the pressing force in the second step is specifically 100 to 200 sec.

(Third process)
Next, the pressure in the upper vacuum region 5 is further increased and held. Then, the diaphragm sheet 4 further expands and presses the module laminate 20 with a greater force than in the second step.

  By applying a higher pressing force than in the second step and bringing the members of the module laminate 20 into close contact with each other, the intermolecular force can be increased and the adhesive force of the filler 22 can be increased.

  The pressing force in the third step is preferably 2.5 to 3.5 times the pressing force in the second step, specifically 45 kPa to 75 kPa.

  In addition, since the filler 22 has already filled macro irregularities and gaps in the pressing in the second step, the filling time of the filler 22 in the poorly fluid portion in the pressing in the third step is shortened, When the material 22 is melted, the time for pressing at a high pressure can be suppressed.

  The holding time of the pressing force in the third step is shorter than the holding time of the pressing force in the second step, and is 15% to 50% of the holding time of the pressing force in the second step, specifically 30 sec to 50 sec. Good.

  Moreover, heating of the module laminated body 20 is continued also during a 3rd process. By adjusting the pressing force and pressing time of each step as described above while raising the temperature of the filler 22 between the first step and the third step, the fluidity of the filler 22 at the temperature of each step is adjusted. It is possible to apply a pressing force suitable for the change of the above, and to efficiently fill the solar cell module with the filler.

  As a result, the back surface side filler 22b whose temperature is increased and the fluidity is increased is prevented from wrapping around the light receiving surface side of the solar cell element 25, and the adhesive force of the filler 22 is increased, and the appearance is excellent and the power generation efficiency is high. The solar cell module 30 can be manufactured, and by ensuring the thickness of the filler 22 at the peripheral edge of the module laminate 20, it is possible to increase the strength against moisture intrusion from the peripheral edge and improve the reliability. it can.

  In addition, the tact time of the laminating process can be shortened to improve productivity, and the holding time of the pressing force can be shortened to reduce the probability of occurrence of cracks in the solar cell element 25 and improve the yield. .

(Fourth process)
Next, the upper vacuum region 5 is depressurized, and the diaphragm sheet 4 contracts as shown in FIG. 1 (b) to monotonously reduce the pressing force to the module laminated body 20, whereby the second step and the third step. It should be lower than the pressing force.

(Fifth process)
Next, the module laminate 20 is held for a predetermined time in a state where a lower pressing force is applied than in the second step and the third step, so that the translucent substrate 21, the matrix 23, the back surface protective material 24, and the filler It is possible to increase the adhesive force by increasing the mechanical bond between the constituent members of the solar cell module 30 and the filler 22 and the intermolecular force.

  By providing the fourth step and the fifth step, the time for pressing with a high pressing force in the third step can be shortened. The pressing force of the fifth step is preferably 15% to 50%, more preferably 15% to 25% of the second step, and specifically, pressing may be performed with a pressing force of 2 kPa to 10 kPa.

  After passing from the first step to the fifth step, the upper vacuum region 5 and the lower vacuum region 6 are returned to atmospheric pressure, the upper housing 2 is opened, and the laminated module laminate 20 is taken out. The laminated module laminate 20 is heated in a crosslinking furnace until the degree of crosslinking of the filler 22 becomes 90% or more. The heating temperature is preferably maintained at 120 to 150 ° C. Thereafter, the terminal box 27 made of polyphenylene ether resin or the like is fixed to the non-light receiving surface side with an adhesive. Thus, a solar cell module is manufactured.

  Here, for example, in order to confirm the effect of the present invention, a solar cell module manufactured by a method of increasing the pressing force monotonously from the conventional second step to the fourth step, and a solar cell manufactured using the manufacturing method of the present invention Prepare the module and compare it as shown in FIG.

  In the solar cell module manufactured by the conventional method, about 1.2 mm to 2 mm of the peripheral portion of the solar cell element 25 is covered with the colored back-side filler 22b that has come around, and the peripheral portion of the solar cell element 25 Became a meandering appearance. For this reason, it becomes a low-precision solar cell module. Furthermore, the power generation efficiency corresponding to the area covered by the colored back surface side filler 22b is lowered.

  If a solar cell element 25 of 15 cm × 15.5 cm is used and the back side filler is uniformly wrapped around the periphery, the amount of power generation per solar cell element 25 is approximately calculated by area ratio. It is thought that it has decreased by 1.6% to 2.6%.

  On the other hand, in the solar cell module using the manufacturing method of the present invention, the peripheral portion of the solar cell element 25 is not covered with the back surface side filler 22b, and the peripheral portion of the solar cell element has a linear appearance and accuracy. It was confirmed that the power generation efficiency can be maintained at a high level.

1: Laminator 2: Upper housing 3: Lower housing 4: Diaphragm sheet 5: Upper vacuum chamber 6: Lower vacuum chamber 7: Upper vacuum pump 8: Heating plate
10: Lower vacuum pump 20: Module laminate 21: Translucent substrate 22a: Light receiving surface side filler 22b: Back surface side filler 23: Matrix 24: Back surface side protective material 25: Solar cell element 26: Conductor 28: Frame 30 : Solar cell module 31: protrusion

Claims (5)

In a method for manufacturing a solar cell module in which a solar cell element is sealed between a substrate and a protective material via a filler, a light-transmitting substrate, a light-receiving surface-side filler, a solar cell element, and a back-side filler And a laminating step of laminating the back side protective material in this order to form a module laminate,
A first step of raising the filler above the melting point temperature; a second step of pressing the module laminate at a pressure higher than the first step; and the module laminate at a pressure higher than the second step. The manufacturing method of the solar cell module characterized by having a 3rd process which presses, and a 4th process which decompresses monotonously from the maximum pressure of this 3rd process. The method for manufacturing a solar cell module according to claim 1, wherein the temperature of the filler is monotonously increased from the first step to the third step. The time required for said 3rd process is 15%-50% of the time required for said 2nd process, The manufacturing method of the solar cell module of Claim 1 or 2 characterized by the above-mentioned. The method for manufacturing a solar cell module according to any one of claims 1 to 3, wherein the pressure in the third step is 250% to 350% of the pressure in the second step. 5. A fifth step of pressing the module laminate at a pressure higher than that of the first step and lower than that of the second step after the fourth step. The manufacturing method of the solar cell module of description.