JP6661051B2 - Solar cell module and method of manufacturing solar cell module - Google Patents

Description

  The present invention relates to a solar cell module in which solar cells are sealed between a light receiving surface side protection member and a back surface side protection member, and a method for manufacturing a solar cell module.

  2. Description of the Related Art Conventionally, as one of mounting structures of a solar cell module, there is a structure using an ethylene-vinyl acetate (EVA) copolymer as a sealing material. Hereinafter, the ethylene-vinyl acetate copolymer may be simply referred to as EVA.

  At the time of manufacturing a solar cell module, as shown in Patent Document 1, a transparent surface member, a transparent surface sealing material, a solar cell constituting a photovoltaic element, a back surface sealing material, and a back surface member were laminated in this order. A laminate is formed, and a sealing process is performed in a laminating apparatus. EVA is used as the surface sealing material and the back surface sealing material, and the solar cell module is sealed by melting and curing the EVA by heating and pressing the laminate using a laminating apparatus. The front surface sealing material and the back surface sealing material are members necessary for ensuring insulation performance in addition to sealing performance.

  Further, the solar cell module is often installed on the roof of a house. In a solar cell module, generally, a plurality of square solar cells are arranged in a matrix in accordance with the shape of the installation surface of the solar cell module.

  On the other hand, when the installation surface is trapezoidal or triangular, the solar cells cannot be arranged in a matrix. Therefore, the shape of the solar cell module is also adapted to the installation surface, and the arrangement of the solar cells must be stepped on the side corresponding to the trapezoidal or triangular hypotenuse of the installation surface. For this reason, the solar cell module has a step-like shape near the hypotenuse, which is a combination of a trapezoidal shape, and a blank area where no solar cell is arranged is formed.

  On the other hand, as shown in Patent Document 2, it has been proposed to dispose a triangular dummy cell in a blank area or to color the blank area in the same color as a solar cell. In order to color the blank area in the same color as the solar cell, a design sheet can be used. Generally, such a design sheet includes a resin sheet made of a resin such as polyethylene terephthalate (PET), which has been subjected to a pressure treatment so that there is no gap, so that the color can be more clearly recognized. used.

Japanese Patent No. 2915327 Japanese Patent No. 3410315

  However, when the above-mentioned design sheet is arranged with respect to the above Patent Document 1, the sealing material does not reach the surface of the design sheet where the non-fluid design sheet is in contact with components other than the sealing material, and the surface of the design sheet does not reach the surface of the design sheet. Bubbles are generated on the surface, and poor appearance is caused by the bubbles.

  The present invention has been made in view of the above, and an object of the present invention is to provide a solar cell module capable of suppressing a decrease in appearance quality due to generation of bubbles.

  In order to solve the above-described problems and achieve the object, a solar cell module according to the present invention includes a light-receiving surface-side protection member that is disposed on the light-receiving surface and has light transmittance, A rear surface side protection member arranged, a solar cell string in which a plurality of solar cells are electrically connected in series with inter-cell tabs, and a horizontal tab in which a plurality of solar cell strings are electrically connected in series, An output tab for extracting an output from the solar cell string to the outside of the back surface side protection member. Further, the solar cell module includes a sealing layer made of resin and sandwiching the solar cell string between the light receiving surface side protection member and the back surface side protection member, and an output tab disposed between the output tab and the horizontal tab. An insulating sheet that insulates the side and the side tab, a design sheet disposed on the back side of the insulating sheet to cover the outer peripheral side of the solar cell string, and a side tab and the insulating sheet disposed between the side tab and the insulating sheet. And a second intermediate sealing layer disposed between the insulating sheet and the design sheet to bring the insulating sheet and the design sheet into a non-contact state. .

  ADVANTAGE OF THE INVENTION According to this invention, there exists an effect that the solar cell module which can suppress the fall of appearance quality by generation | occurrence | production of a bubble is obtained.

Sectional drawing which shows typically the structure of the arrangement | positioning area | region of the solar cell in the solar cell module concerning Embodiment 1 of this invention. FIG. 2 is a schematic view of the solar cell module according to the first embodiment of the present invention as seen through from the back side. FIG. 1 is a schematic diagram showing a connection configuration of an electric circuit of a solar cell module according to a first embodiment of the present invention. FIG. 2 is a schematic plan view of the solar cell module according to the first embodiment of the present invention as viewed from the back side. FIG. 3 is a conceptual diagram illustrating a configuration around an end of a solar cell string in the solar cell module according to the first embodiment of the present invention, and is a conceptual diagram illustrating a configuration of a region X where an insulating sheet is arranged in FIG. 2. FIG. 3 is a conceptual diagram illustrating a configuration around an end of a solar cell string in the solar cell module according to the first embodiment of the present invention, and is a conceptual diagram illustrating a configuration of a region Y1 where an insulating sheet is not arranged in FIG. Flow chart showing a procedure of a method for manufacturing a solar cell module according to Embodiment 1 of the present invention. FIG. 4 is a conceptual diagram schematically showing a stacked structure around an end portion of an S2 upper side tab of a horizontal tab between S1 and S2 of the stacked body in the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. FIG. 4 is a conceptual diagram schematically showing a configuration around an S4 upper tab of a horizontal tab between S4 and S5 of the laminate in the method of manufacturing a solar cell module according to Embodiment 1 of the present invention, and around an end of a design sheet. FIG. 3 is an enlarged view schematically showing a state before laminating the first intermediate sealing layer sheet and the insulating sheet in the laminating step of the method for manufacturing a solar cell module according to the first embodiment of the present invention. FIG. 2 is an enlarged plan view schematically showing a state in which the first intermediate sealing layer sheet and the insulating sheet are stacked in the stacking step of the method for manufacturing a solar cell module according to the first embodiment of the present invention. Top view of the insulating sheet laminated in the laminating step of the method for manufacturing a solar cell module according to the first embodiment of the present invention Sectional drawing of the insulating sheet laminated | stacked in the lamination process of the manufacturing method of the solar cell module concerning Embodiment 1 of this invention An enlarged plan view schematically showing a state in which a second intermediate sealing layer sheet is laminated in a laminating step of the method for manufacturing a solar cell module according to the first embodiment of the present invention. FIG. 2 is an enlarged plan view schematically showing a state in which design sheets are stacked in a stacking step of the method for manufacturing a solar cell module according to the first embodiment of the present invention. Schematic view of the laminate in Example 2 seen from the back side Sectional view of a principal part, which is a peripheral portion of the upper side tab of the horizontal tab between S1-S2 of the laminate in Example 2 and around the end of the design sheet. Sectional view of the main part, which is a peripheral portion of the upper side tab of S4 between S4-S5 of the laminated body in Example 2, and schematically shows the configuration around the end portion of the design sheet. FIG. 7 is a conceptual diagram schematically showing a stacked configuration around an end of an S2 upper side tab of a horizontal tab between S1 and S2 of a laminate in Comparative Example 1, and around an end of a design sheet. It is a peripheral part of the S4 upper side tab of the horizontal tab between S4-S5 of the laminated body in Comparative Example 1, and is a conceptual diagram schematically showing the configuration around the end of the design sheet. FIG. 7 is a conceptual diagram schematically illustrating a stacked configuration around an end portion of an S2 upper side tab of a horizontal tab between S1 and S2 of a laminate in Comparative Example 2, and around an end portion of a design sheet. It is a peripheral part of the S4 upper side tab of the horizontal tab between S4-S5 of the laminated body in the comparative example 2, and is a conceptual diagram which shows typically the structure around the end part of a design sheet. FIG. 7 is a conceptual diagram schematically illustrating a stacked configuration around an end of an S2 upper side tab of a horizontal tab between S1 and S2 of a laminated body in Comparative Example 3, and around an end of a design sheet. It is a peripheral part of the S4 upper side tab of the horizontal tab between S4-S5 of the laminated body in the comparative example 3, and is a conceptual diagram which shows typically the structure around the end part of a design sheet. The figure which shows the evaluation result of the presence or absence of the bubble generation of the sample of an Example and a comparative example FIG. 4 is a schematic view showing a bubble generation region where a bubble is generated in a portion of the sample of Comparative Example 1 where the second intermediate sealing layer sheet is not covered. In the sample of Comparative Example 2, a portion of the sample not covered with the second intermediate sealing layer sheet, which is a schematic diagram showing a bubble generation region where bubbles are generated. In the sample of Comparative Example 3, a portion where the second intermediate sealing layer sheet is not covered, and is a schematic diagram showing a bubble generation region where bubbles are generated.

  Hereinafter, a solar cell module and a method for manufacturing the solar cell module according to an embodiment of the present invention will be described in detail with reference to the drawings. The present invention is not limited by the embodiment.

Embodiment 1 FIG.
Hereinafter, embodiments of a solar cell module and a method of manufacturing a solar cell module according to the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following description, and can be appropriately modified without departing from the gist of the present invention. Further, in the drawings described below, the scale of each member may be different from the actual scale for easy understanding. Similarly, between the drawings, the scale of each member may be different from the actual scale. Also, hatching may be used even in a plan view so as to make the drawings easy to see. Further, hatching may not be used even in a cross-sectional view so as to make the drawings easy to see.

  FIG. 1 is a cross-sectional view schematically showing a configuration of a solar cell arrangement region in the solar cell module according to the first embodiment of the present invention. FIG. 2 is a schematic diagram of the solar cell module according to the first embodiment of the present invention as seen through from the back surface side. FIG. 3 is a schematic diagram illustrating an electrical circuit connection configuration of the solar cell module according to the first embodiment of the present invention. FIG. 4 is a schematic plan view of the solar cell module according to the first embodiment of the present invention as viewed from the back side. FIG. 5 is a conceptual diagram showing a configuration around the end of the solar cell string in the solar cell module according to the first embodiment of the present invention, and shows a configuration of a region X where the insulating sheet 72 is arranged in FIG. It is a conceptual diagram. FIG. 6 is a conceptual diagram showing a configuration around an end of the solar cell string in the solar cell module according to the first embodiment of the present invention, and shows a configuration of a region Y1 where the insulating sheet 72 is not arranged in FIG. It is a conceptual diagram.

  Note that FIGS. 5 and 6 mainly show the inclusion relation, that is, the positional relation of each component in the surface direction of the solar cell module 50. Although the thickness of the solar cell module is shown differently in FIG. 5 and FIG. 6, the output tab 11, the horizontal tab 21 between S1 and S2, and the insulating sheet 72 have a thickness of 0.1 mm or less. Since the solar cell module has a small thickness, the thickness of the sealing layer in the solar cell module 50 differs depending on the region, so that the entire solar cell module has the same thickness. In FIGS. 5 and 6, the region of the sealing layer is hatched for easy understanding.

  First, the configuration of the area where the solar cells are arranged in the solar cell module 50 according to the first embodiment will be described. As shown in FIG. 1, the solar cell module 50 according to the first embodiment includes, as shown in FIG. 1, a light-transmitting substrate 1 which is a light-receiving surface side protection member disposed on the light-receiving surface A side, and 1, a light-receiving surface sealing layer 2 which is a sealing material, a plurality of solar cells 3 connected by an inter-cell tab 4 and arranged on the same surface, and a rear surface B side facing the light-receiving surface A A back surface sealing layer 5 as a second sealing material and a back sheet 6 as a back surface covering film as a back surface protection member disposed on the back surface are sequentially laminated. In the solar cell module 50, a holding frame (not shown) for holding the periphery is attached to the outer periphery, and a terminal box is adhered to the back surface of the solar cell module. In the solar cell module 50, sunlight enters from the front side of the translucent substrate 1.

  The translucent substrate 1 is made of a glass material or a synthetic resin material such as a polycarbonate resin. The sunlight enters the light receiving surface of the light transmitting substrate 1. Here, a light-transmitting glass substrate is used as the light-transmitting substrate 1, but a resin plate or the like may be used as long as the material has a light-transmitting property. The translucent substrate 1 is fixed to the outer surface of the light-receiving surface sealing layer 2 located on the light-receiving surface A side of the solar cell module 50.

  EVA which is a resin having thermoplasticity and light transmittance is used for the light-receiving surface sealing layer 2. In the first embodiment, EVA is used for the light-receiving surface sealing layer 2. In addition, a translucent thermosetting resin such as polyethylene, polypropylene, polycarbonate, polyurethane resin, and polyolefin resin is used. Alternatively, it is possible to use the laminate. Furthermore, it is effective to crosslink the sealing resin used for the light receiving surface sealing layer 2 in order to improve weather resistance, strength and adhesiveness. The adhesiveness of the light-receiving surface sealing layer 2 is required to have adhesiveness to the solar cell 3 in addition to adhesiveness to the translucent substrate 1. As a crosslinking method, a method of generating a radical by heat is effective. Further, it is preferable to add an ultraviolet absorber in order to improve light resistance. However, in order to improve the output of the solar cell module, it is preferable to reduce the amount of the ultraviolet absorber.

  The same material as the light receiving surface sealing layer 2 can be used for the back surface sealing layer 5. In addition, it is preferable that the back surface sealing layer 5 is white from the viewpoint of ensuring design and power generation. The reason why the resin forming the back surface sealing layer 5 is preferably white is that sunlight that has entered from the translucent substrate 1 and has reached the back surface sealing layer 5 is reflected by the white resin and has an optical path length. This is for re-entering the solar cell 3 without loss and contributing to power generation. The light-receiving surface sealing layer 2 and the back surface sealing layer 5 form a sealing layer that sandwiches the solar cell 3 between the translucent substrate 1 and the back sheet 6.

  The back sheet 6 is fixed to the outer surface of the back surface sealing layer 5 located on the back surface B side facing the light receiving surface of the solar cell module 50, and has a function of protecting the solar cells 3 from moisture. . The back sheet 6 is preferably made of a resin having high adhesion to the back surface sealing layer 5 on the surface in contact with the back sheet. The outermost layer on the atmosphere side of the back sheet 6 is preferably a resin having high weather resistance such as polyethylene terephthalate (PET) or polyvinylidene phthalate (PVF).

  As the solar cell 3, a solar cell including a crystalline solar cell can be used. Examples of the crystalline solar cell include a single-crystal silicon solar cell and a polycrystalline silicon solar cell.

  As shown in FIGS. 2 and 3, a plurality of solar cells 3 are electrically connected by inter-cell tabs 4 to form a solar cell string S5 from a solar cell string S1. The solar cell strings S5 to S5 are arranged to form a solar cell array, which is a group of solar cells. Hereinafter, the solar cell string may be referred to as a string. 2 and 3, the number of inter-cell tabs 4 connecting the solar cells 3 is two, but the number of inter-cell tabs 4 connecting the solar cells 3 may be three or more. The vertical direction is the same as the direction in which the solar cells 3 are connected by the inter-cell tabs 4. The left-right direction is the same direction as the direction in which the strings S1 to S5 are arranged.

  In FIG. 2, the string S1 in the first column from the left includes three solar cells 3, the back electrode 3b of the upper solar cell 3 of the solar cells 3 in the string S1, and the lower solar cell. And a cell-to-cell tab 4 for electrically connecting the light-receiving surface electrode 3a to the third light-receiving surface electrode 3a.

  In FIG. 2, the string S2 in the second column from the left includes four solar cells 3, the back electrode 3b of the lower solar cell 3 of the upper and lower solar cells 3 in the string S2, and the upper solar cell. And an inter-cell tab 4 for electrically connecting the light receiving surface electrode 3a of the battery cell 3 to the light receiving surface electrode 3a. The strings S <b> 1 and S <b> 2 are arranged so that the positions of the lowermost solar cells 3 are aligned. The string S1 and the string S2 are electrically connected by a horizontal tab 21 between S1 and S2 below the lowermost solar cell 3.

  In FIG. 2, the string S3 in the third column from the left includes five solar cells 3, the back electrode 3b of the upper solar cell 3 of the upper and lower solar cells 3 in the string S3, and the lower solar cell. And an inter-cell tab 4 for electrically connecting the light receiving surface electrode 3a of the battery cell 3 to the light receiving surface electrode 3a. The string S1, the string S2, and the string S3 are arranged so that the positions of the lowermost solar cells 3 are aligned. The strings S2 and S3 are electrically connected by the horizontal tab 22 between S2 and S3 on the upper side of the uppermost solar cell 3.

  The string S2 and the string S3 are different in height on the upper side by one solar cell 3. For this reason, in order to electrically connect the photovoltaic cells 3 located at different positions, the horizontal tab 22 between S2 and S3 is connected to the intercell tab connected to the uppermost photovoltaic cell 3 of the string S3. S3 upper tab 22a electrically connected to the S4 upper tab, S2 upper tab 22b electrically connected to the inter-cell tab 4 connected to the uppermost solar cell 3 of the string S2, S3 upper tab and S2 upper tab. And an S2-S3 connection tab 22c for connecting the left side of the uppermost solar cell 3 of the string S3, that is, the string S2 side. The S3 upper tab 22a is electrically connected to the inter-cell tab 4 above the uppermost solar cell 3 of the string S3. The S2 upper tab 22b is electrically connected to the inter-cell tab 4 above the uppermost solar cell 3 of the string S2.

  In FIG. 2, the string S4 in the fourth column from the left includes six solar cells 3, the back electrode 3b of the lower solar cell 3 of the upper and lower solar cells 3 in the string S4, and the upper solar cell. And a cell-to-cell tab 4 for connecting the light receiving surface electrode 3a of the battery cell 3 to the cell. The strings S3 and S4 are arranged such that the positions of the lowermost solar cells 3 are aligned. The strings S3 and S4 are electrically connected by a horizontal tab 23 between S3 and S4 below the lowermost solar cell 3.

  In FIG. 2, the string S5 in the fifth column from the left includes seven solar cells 3, the back electrode 3b of the upper solar cell 3 among the upper and lower solar cells 3 in the string S5, and the lower solar cell. And a cell-to-cell tab 4 for connecting the light receiving surface electrode 3a of the battery cell 3 to the cell. The strings S4 and S5 are arranged such that the positions of the lowermost solar cells 3 are aligned. The strings S4 and S5 are connected by a horizontal tab 24 between S4 and S5 above the uppermost solar cell 3.

  The string S4 and the string S5 are different in height on the upper side by one solar cell 3. Therefore, in order to electrically connect the photovoltaic cells 3 located at different positions, the horizontal tabs 24 between S4 and S5 are connected to the intercell tabs connected to the uppermost photovoltaic cell 3 of the string S5. S4 upper tab 24a electrically connected to the uppermost solar cell 3 of the string S4, the S4 upper tab 24b electrically connected to the inter-cell tab 4 connected to the uppermost solar cell 3 of the string S4, and the S5 upper tab 24a and the upper S4. An S4-S5 connection tab 24c for connecting the tab 24b to the left side of the uppermost solar cell 3 of the string S5. The S5 upper tab 24a is electrically connected to the inter-cell tab 4 above the uppermost solar cell 3 of the string S5. The S4 upper tab 24b is electrically connected to the inter-cell tab 4 above the uppermost solar cell 3 of the string S4.

  In addition, as shown in FIGS. 2 and 3, the output is taken out of the backsheet 6, that is, outside the solar cell module 50, from the uppermost solar cell 3 of the string S <b> 1 in the first column from the left in the figure. Output tab 11 is taken out of the solar cell module. The take-out position is near the back side of the uppermost solar cell 3 of the string S2 for taking out together with a take-out tab 31 described later. Therefore, the output tab 11 is wired from above the uppermost solar cell 3 of the string S1 to near the back side of the uppermost solar cell 3 of the string S2. The back sheet 6 at the take-out position is provided with a take-out hole 6a.

  From the S2 upper tab 22b, an extraction tab 31 for connection to a later-described bypass diode 41 is extracted outside the solar cell module. The take-out position is near the back side of the uppermost solar cell 3 of the string S2, and a take-out hole 6a is provided in the back sheet 6 at the take-out position.

  The negative terminal box 51 is bonded to the back surface of the back sheet 6 so as to cover the take-out hole 6a of the back sheet 6 between the output tab 11 and the take-out tab 31. Inside the negative terminal box 51, a bypass diode 41 is connected between the output tab 11 and the extraction tab 31 so that the direction from the output tab 11 to the extraction tab 31 is forward. A negative output cable 52 is connected to the outside of the negative terminal box 51 from a connection point between the output tab 11 and the bypass diode 41.

  In the figure, the output tab 12 for taking out the output is taken out of the solar cell module 50 from the bottom of the string S5 in the fifth column from the left. The take-out position is near the back side of the lowermost solar cell 3 of the string S4 for taking out together with take-out tabs 32, 33 described later. Therefore, the output tab 12 is wired from below the bottom solar cell 3 of the string S5 to near the back side of the bottom solar cell 3 of the string S4. The back sheet 6 at the take-out position is provided with a take-out hole 6b.

  A takeout tab 33 for connecting to the bypass diodes 42 and 43 is taken out of the solar cell module 50 from the horizontal tab 23 between S3 and S4 that connects the strings S3 and S4 at the bottom of the lowermost stage. The take-out position is a take-out hole 6b provided in the back sheet 6 near the back side of the lowermost solar cell 3 of the string S4.

  An extraction tab 32 for connecting to the bypass diode 42 is extracted outside the solar cell module 50 from the horizontal tab 21 between S1 and S2 that connects the strings S1 and S2 at the lowermost lower side. The take-out position is a take-out hole 6b provided in the back sheet 6 near the back side of the lowermost solar cell 3 of the string S4.

  The positive terminal box 53 is adhered to the back surface of the back sheet 6 so as to cover the take-out hole 6b of the back sheet 6 from which the output tab 12, the take-out tab 32, and the take-out tab 33 are taken out. Inside the positive terminal box 53, a bypass diode 41 is connected between the output tab 11 and the extraction tab 31 so that the direction from the output tab 11 to the extraction tab is forward. A positive output cable 54 is connected to the outside of the positive terminal box 53 from a connection point between the output tab 12 and the bypass diode 43.

Next, the configuration around the end of the solar cell string in the solar cell module 50 will be described. In FIG. 5, the configuration around the end of the uppermost stage solar cell 3 of the string S <b> 2, that is, the periphery of the S2 upper tab 22 b of the horizontal tab 22 between S <b> 2 and S <b> 3 and around the end of the design sheet 74 is schematically shown. Is shown in In FIG. 6, the configuration around the end of the uppermost stage solar cell 3 of the string S4, that is, the periphery of the S4 upper tab 24b of the horizontal tab 24 between S4 and S5, and around the end of the design sheet 74 is schematically shown. Is shown in

In the peripheral portion of the S2 upper tab 22b, as shown in FIG. 5, the light receiving surface sealing layer 2, the S2 upper tab 22b of the lateral tab 22 between S2 and S3 , and the first intermediate The sealing layer 71, the insulating sheet 72, the second intermediate sealing layer 73, the output tab 11, the design sheet 74, the back surface sealing layer 5, and the back sheet 6 are laminated. Note that, depending on the position, there is an area where any of the above-described components does not exist. The above-described components are provided along a plane parallel to the in-plane direction of the translucent substrate 1.

In the periphery of the S4 upper tab 24b, as shown in FIG. 6, the light receiving surface sealing layer 2, the inter-cell tab 4, the design sheet 74, and the back surface sealing layer 5 are formed on the translucent substrate 1. And the back sheet 6 are stacked. Although the thickness of the solar cell module is shown differently in FIG. 5 and FIG. 6, the output tab 11, the horizontal tab 22 between S2 and S3, and the insulating sheet 72 have a thickness of 0.1 mm or less. Since the solar cell module has a small thickness, the thickness of the sealing layer in the solar cell module differs depending on the region, so that the entire solar cell module has the same thickness.

The first intermediate sealing layer 71, in the plane direction of the insulating sheet 72, and includes a first overlapping region S2 upper tab 22b of S2-S3 between the lateral tabs 22 and the insulating sheet 72 overlap, S2- It is arranged between the S2 upper tab 22b of the horizontal tab 22 between S3 and the insulating sheet 72. The same material as the light receiving surface sealing layer 2 can be used for the first intermediate sealing layer 71.

The insulating sheet 72 is sandwiched and fixed between the first intermediate sealing layer 71 and the second intermediate sealing layer 73 inside the solar cell module 50. Insulating sheet 72, insulation between and S2 upper tab 22b of the output tabs 11 and the output tab 11 is disposed between and S2 upper tab 22b of the lateral tabs 22 between S2-S3 and S2-S3 between the lateral tabs 22 Has the function of increasing In addition, the insulating sheet 72 is disposed between the output tab 11 and the solar cell 3 and has a function of increasing the insulation between the output tab 11 and the solar cell 3. The first intermediate sealing layer 71 is in close contact with the entire surface of the insulating sheet 72 on the light receiving surface side. In addition, the entire surface of the insulating sheet 72 on the back surface side is in close contact with the second intermediate sealing layer 73.

  It is preferable that the insulating sheet 72 be a resin having high adhesion to the first intermediate sealing layer 71 and the second intermediate sealing layer 73 on the surface in contact with the first intermediate sealing layer 71 and the second intermediate sealing layer 73. In addition, it is preferable that the insulating sheet 72 be a resin having high adhesion to the back surface sealing layer 5 on the surface in contact with the back surface sealing layer 5. As the insulating sheet 72, a PET sheet or a resin sheet having an insulating property such as polyvinylidene phthalate can be used.

  The second intermediate sealing layer 73 includes a second overlapping area where the output tab 11 and the insulating sheet 72 overlap the design sheet 74 in the surface direction of the insulating sheet 72, and includes the output tab 11 and the insulating sheet 72. 72 and a design sheet 74. The same material as the light receiving surface sealing layer 2 can be used for the second intermediate sealing layer 73.

  The design sheet 74 is arranged on the back side of the insulating sheet 72 and fixed inside the solar cell module 50, and covers the outer peripheral side of the solar cell 3 to enhance the design of the solar cell module 50. The design sheet 74 is not arranged above the solar cell 3. As shown in FIG. 5, the design sheet 74 is sandwiched and fixed between the second intermediate sealing layer 73 and the back surface sealing layer 5 around the S2 upper tab 22b. The output tab 11 is in contact with a part of the design sheet 74 on the light receiving surface side. 6, the design sheet 74 is sandwiched and fixed between the light-receiving surface sealing layer 2 and the back surface sealing layer 5 around the S4 upper tab 24b, as shown in FIG. The S4 upper tab 24b is in contact with a part of the design sheet 74 on the light receiving surface side.

  It is preferable that the design sheet 74 has high adhesion to the second intermediate sealing layer 73 on the surface in contact with the second intermediate sealing layer 73. Further, it is preferable that the design sheet 74 has high adhesion to the light receiving surface sealing layer 2 and the back surface sealing layer 5 on the surface in contact with these. The design sheet 74 has a structure in which fibers are folded, such as a nonwoven fabric having a large specific surface area, in order to increase the adhesion between the second intermediate sealing layer 73, the light receiving surface sealing layer 2, and the back surface sealing layer 5. Is preferred. The material of the nonwoven fabric is preferably a resin having high weather resistance such as PET or PVF. In the first embodiment, a nonwoven fabric sheet is used as the design sheet 74. In the first embodiment, by using a nonwoven fabric sheet made of PET as the design sheet 74, the adhesion between the second intermediate sealing layer 73, the light receiving surface sealing layer 2, and the back surface sealing layer 5 can be improved. I have. The design sheet 74 may be a sheet made of a solid PET material having no space inside, that is, no void inside.

  The solar cell module 50 has a trapezoidal shape in which one side is an oblique side by increasing the number of solar cells 3 connected in series for each string row as shown in FIG. Since the photovoltaic cells 3 have a square plate shape, the edges on the oblique side of the photovoltaic cell group are stepped. Therefore, a sawtooth-shaped blank region in which a plurality of triangles are connected with the tops overlapping each other is formed between the solar cell group and the hypotenuse. A design sheet 74 having substantially the same shape as the region and having the same color as the solar cell 3 is arranged in this region so as to cover the entire region. The outer peripheral edge of the solar cell module 50 is covered over the entire periphery by a frame (not shown).

  As described above, in the solar cell module 50 having such a configuration, the design sheet 74 having the same color tone as that of the solar cell 3 is arranged in a blank area other than the area where the solar cell 3 is arranged. By arranging the design sheet 74 having the same color as the solar cell 3 and the solar cell 3, the solar cell module 50 does not have a sense of incongruity in appearance and is excellent in design.

  In the solar cell module 50, if the blank area has an area formed between the frame and the solar cell 3, the design sheet 74 can be disposed to improve the appearance. Obtainable.

  Next, a method for manufacturing the solar cell module 50 will be described. FIG. 7 is a flowchart illustrating a procedure of a method for manufacturing a solar cell module according to Embodiment 1 of the present invention. The light receiving surface sealing layer sheet 2s is a sheet made of the material constituting the light receiving surface sealing layer 2 described above. The first intermediate sealing layer sheet 71s is a sheet made of the material constituting the first intermediate sealing layer 71 described above. The second intermediate sealing layer sheet 73s is a sheet made of the material constituting the second intermediate sealing layer 73 described above. The back surface sealing layer sheet 5s is a sheet made of the material constituting the back surface sealing layer 5 described above.

FIG. 8 is a diagram showing the peripheral portion of the upper tab S2 of the horizontal tab between S2-S3 of the laminate in the method of manufacturing the solar cell module according to Embodiment 1 of the present invention, and schematically shows the laminated configuration around the end of the design sheet. FIG. That is, FIG. 8 shows a cross-sectional view of a main part of a portion corresponding to the region X in FIG. FIG. 9 is a diagram showing the periphery of the S4 upper tab of the horizontal tab between S4 and S5 in the method of manufacturing the solar cell module according to Embodiment 1 of the present invention, and schematically shows the configuration around the end of the design sheet. FIG. That is, FIG. 9 is a cross-sectional view of a main part of a portion corresponding to the region Y1 in FIG. 8 and 9 mainly show the inclusion relation, that is, the positional relation of each component in the surface direction of the solar cell module 50. FIG. FIG. 8 shows a laminated configuration around the S2 upper tab of the horizontal tab between S2 and S3 of the laminate. Further, the laminated configuration around the S4 upper tab of the horizontal tab between S4 and S5 of the laminate is the configuration shown in FIG.

  The method for manufacturing the solar cell module 50 according to the first embodiment includes a light-transmitting substrate 1, a light-receiving surface sealing layer sheet 2s that is a first sealing layer sheet, a solar cell string, and a first intermediate. A sealing layer sheet 71s, an insulating sheet 72, a second intermediate sealing layer sheet 73s, a design sheet 74, a back sealing layer sheet 5s as a second sealing layer sheet, a back sheet 6, And a sealing step of heating and pressurizing the laminate by a lamination process to seal the solar cell 3 between the translucent substrate 1 and the back sheet 6. ,including.

  First, in step S101, the solar cell 3 is formed. Next, in step S102, the string S is formed by fixing the inter-cell tabs 4 to the solar cells 3 to connect the plurality of solar cells 3 with the inter-cell tabs 4. Subsequently, in the laminating step of Step S103, a laminated body is formed. The laminate is formed by sequentially laminating a light-receiving surface sealing layer sheet 2s and a string S on a light-transmitting substrate 1 made of a light-transmitting glass substrate. Furthermore, a first intermediate sealing layer sheet 71 s for the purpose of filling the sealing material and suppressing generation of bubbles in a portion in contact with the insulating sheet 72, an insulating sheet 72 for the purpose of insulation, and a filling and insulating sheet for the sealing material The second intermediate sealing layer sheet 73 s for the purpose of suppressing the generation of bubbles at the portion in contact with the design sheet 72 and the design sheet 74, the design sheet 74 for the purpose of improving the design, the back surface sealing layer sheet 5 s, and the back sheet 6 The layers are sequentially laminated on the string S to form a laminated body.

  Then, in step S104, a decompression step is performed to reduce the pressure in the laminating apparatus (not shown) into which the laminate obtained in step S103 is loaded. Next, in the sealing step of step S105, a batch heat treatment step was performed to heat and pressurize the laminate in the melt-pressing step, and then the laminate was cooled, whereby the solar cell 3 was sealed. The solar cell module 50 is formed. The periphery of the solar cell module 50 is fixed by a frame, and the negative terminal box 51 and the positive terminal box 53 are attached.

  Next, a description will be given of the stacking process in the peripheral portion of the S2 upper tab and the output tab in step S103. FIGS. 10 to 15 show a method of laminating the uppermost solar cell 3 of string S2, an upper tab of S2, and a peripheral portion of the output tab in the laminating step in the method of manufacturing the solar cell module according to Embodiment 1 of the present invention. Is shown.

  FIG. 10 is an enlarged view schematically showing a state before laminating the first intermediate sealing layer sheet and the insulating sheet in the laminating step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. is there. After laminating the light receiving surface sealing layer sheet 2s and the strings S on the translucent substrate 1, as shown in FIG. 10, four cells are arranged from the back electrode 3b of the solar cell 3 to the upper side of the solar cell 3. The inter-tab 4 is connected and connected to the S2 upper tab 22b of the S2-S3 horizontal tab 22 outside the upper side of the solar cell 3. An extraction tab 31 for connecting to the bypass diode 41 is connected to the S2 upper tab 22b of the horizontal tab 22 between S2 and S3, and is pulled out near the rear surface of the uppermost solar cell 3 of the string S2.

  Also, as shown in FIG. 10, an output tab 11 is wired from the upper side of the uppermost solar cell 3 of the string S1 to the left side of the uppermost solar cell 3 of the string S2, as shown in FIG. You. The output tab 11 is located above the S2 upper tab 22b of the horizontal tab 22 and overlaps the S2 upper tab 22b of the horizontal tab 22 in the plane of the solar cell 3, and the back surface of the uppermost solar cell 3 of the string S2. It is pulled out near.

  FIG. 11 is an enlarged plan view schematically illustrating a state where the first intermediate sealing layer sheet and the insulating sheet are stacked in the stacking step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. . FIG. 12 is a top view of the insulating sheet laminated in the laminating step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. FIG. 13 is a cross-sectional view of the insulating sheet laminated in the laminating step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. In FIG. 11, the position of the take-out hole 6a provided in the back sheet 6 is indicated by a broken line.

  The insulating sheet 72 is sandwiched between the S2 upper tab 22b of the horizontal tab 22 and the output tab 11, and insulates the S2 upper tab 22b of the horizontal tab 22 from the output tab 11. Further, the insulating sheet 72 is provided with a cut 61 at a position corresponding to the connection point between the S2 upper tab 22b of the horizontal tab 22 and the takeout tab 31, and the takeout tab 31 extends from the cut 61 to the back surface of the insulating sheet 72. Pulled out to the side. The insulating sheet 72 is sandwiched between the output tab 11 and the extraction tab 31 and the back surface of the uppermost solar cell 3 of the string S2, and the output tab 11 and the extraction tab 31 and the uppermost solar cell of the string S2. The battery cell 3 is insulated.

  The insulating sheet 72 has a rectangular outer shape, the left side is located on the left side of the left end of the S2 upper tab 22b, the right side is located on the right side of the extraction tab 31, and the upper side is located on the upper side of the upper end of the output tab 11. And the size is such that the lower side is located below the take-out hole 6 a provided in the back sheet 6.

  On the surface of the insulating sheet 72 disposed on the light receiving surface side, a first intermediate sealing layer sheet 71s having the same size as the insulating sheet 72 is laminated in advance. The insulating sheet 72 and the first intermediate sealing layer sheet 71s are provided with cuts 61 for sandwiching the extraction tab 31.

  FIG. 14 is an enlarged plan view schematically showing a state in which the second intermediate sealing layer sheet is laminated in the laminating step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. The second intermediate sealing layer sheet 73s is sandwiched between the output tab 11 and the insulating sheet 72. The second intermediate sealing layer sheet 73s is disposed outside the uppermost solar cell 3 of the string S2 so as to cover a portion wider than the insulating sheet 72.

  FIG. 15 is an enlarged plan view schematically illustrating a state in which the design sheets are stacked in the stacking step of the method for manufacturing a solar cell module according to Embodiment 1 of the present invention. The design sheet 74 is stacked in the tooth-shaped blank area between the solar cell group and the hypotenuse so as not to overlap the uppermost solar cell 3 of the string S2.

  When the design sheet 74 made of nonwoven fabric and the insulating sheet 72 made of PET are in contact with each other, only the EVA of the back sealing layer sheet 5s does not allow some EVA to penetrate to the surface of the design sheet 74 made of nonwoven fabric during lamination. For this reason, air bubbles remain on the surface of the design sheet 74, and the air bubbles are confirmed when the solar cell module 50 is viewed from the translucent substrate 1 side. That is, when the EVA does not penetrate to the surface of the design sheet 74, air bubbles are generated between the design sheet 74 and the insulating sheet 72 after the lamination process, that is, the air bubbles are generated on the surface of the design sheet 74 and the surface of the insulating sheet 72. Bubbles may be generated to deteriorate the appearance quality. In addition, due to aging, air bubbles remaining in the nonwoven fabric of the design sheet 74 and air bubbles generated from the EVA may accumulate on the surface of the design sheet 74 and cause a deterioration in appearance quality. That is, due to aging, an aging part in which the adhesion between the EVA of the sealing material and the design sheet 74 is reduced is generated. In this case, the escape area of the gas generated inside the solar cell module concentrates on the aged deterioration portion, and the appearance defect due to bubbles occurs.

  On the other hand, in an area where the insulating sheet 72 is not arranged, such as the area Y1 in FIG. 2, the inter-cell tab 4, the output tab 11, and the horizontal tab between S2-S3 are provided on the transparent sheet 1 side of the design sheet 74. There are tabs such as 22 and a horizontal tab 24 between S4 and S5, and a design sheet 74 made of nonwoven fabric and an EVA of the back surface sealing layer 5 are present in this order on the back sheet 6 side of the tab. In this case, since the tab does not transmit light, there is no problem in appearance quality of the solar cell module 50 when the solar cell module 50 is viewed from the translucent substrate 1 side. Further, since a part of the EVA of the back surface sealing layer 5 penetrates the design sheet 74 made of non-woven fabric and is joined to the tab, there is a problem of adhesion and adhesion between the EVA of the sealing material and the design sheet 74. Not even. Further, since the tab is harder and smaller in width than other insulating sheets or the like, a pressing pressure is apt to be applied at the time of lamination, and EVA easily permeates between the nonwoven fabrics.

  Therefore, in the method of manufacturing a solar cell module according to the first embodiment, the second intermediate sealing layer sheet 73s is filled with EVA between the design sheet 74 made of nonwoven fabric and the insulating sheet 72 made of PET. The second intermediate sealing layer 73 is formed by using this. Thereby, in the solar cell module 50, the EVA surely penetrates to the surface of the design sheet 74, and suppresses the deterioration of the appearance quality due to the generation of bubbles on the surface of the design sheet 74 and the surface of the insulating sheet 72 after lamination. it can. Further, in the solar cell module 50, it is possible to suppress deterioration in appearance quality due to accumulation of bubbles remaining in the nonwoven fabric of the design sheet 74 and bubbles generated from EVA on the surface of the design sheet 74 due to aging.

  That is, in the method for manufacturing a solar cell module according to the first embodiment, in order to prevent the design sheet 74 made of PET and the insulating sheet 72 made of PET from coming into contact with each other in the region X, the purpose is to suppress bubbles. A second intermediate sealing layer 73 made of EVA is provided on the surface of a design sheet 74 made of nonwoven fabric. Thereby, the design sheet 74 and the insulating sheet 72 are brought into a non-contact state, and the generation of bubbles between the design sheet 74 and the insulating sheet 72 can be suppressed. The provision of the second intermediate sealing layer 73 allows EVA to penetrate into the voids of the nonwoven fabric of the design sheet 74, and the large specific surface area of the design sheet 74 allows the design sheet 74 to communicate with the EVA. Adhesion can be enhanced, and generation of air bubbles on the surface of the design sheet 74 made of a nonwoven fabric can be suppressed.

  Even when a design sheet 74a made of a solid PET sheet, which is not a nonwoven fabric, is used, a second intermediate sealing layer 73 made of EVA for the purpose of suppressing bubbles is provided on the surface of the design sheet 74a. In X, the design sheet 74a made of PET and the insulating sheet 72 made of PET are prevented from coming into contact with each other. Thereby, generation of bubbles between the design sheet 74a made of PET and the insulating sheet 72 made of PET can be suppressed.

  When a design sheet 74a made of a solid PET sheet, which is not a nonwoven fabric, is used, in order to prevent the contact between the inter-cell tab 4 and the design sheet 74a in the region Y2, the inter-cell tab 4 is used. A third intermediate sealing layer sheet 75s made of EVA is inserted into a surface facing the design sheet 74a made of a solid PET sheet that is not a nonwoven fabric. Thereby, the inter-cell tab 4 and the design sheet 74a made of a solid PET sheet made of a non-woven fabric are brought into a non-contact state, and the inter-cell tab 4 is brought into contact with the design sheet 74a made of a solid PET sheet made of a non-woven fabric. It is possible to suppress the generation of bubbles between them.

  Therefore, the method for manufacturing the solar cell module 50 according to the first embodiment described above includes the steps of laminating and after long-term use, on the design sheet 74 and the insulating sheet 72 that are visible from the translucent substrate 1 side. Generation of air bubbles can be suppressed. Accordingly, in the method of manufacturing solar cell module 50 of Embodiment 1, no bubbles are generated during production, and no bubbles are generated even in outdoor installation after shipment. The solar cell module 50 capable of suppressing the deterioration of the appearance quality due to the deterioration is obtained.

  At the time of laminating the nonwoven fabric, if the rigidity of the nonwoven fabric is low, the appearance may be poor due to the generation of wrinkles. Therefore, the nonwoven fabric may be folded and used twice.

  In the case where the nonwoven fabric is used by being folded twice, if the dimensions of the overlapping portions are the same, there is a possibility that the ends of the folded nonwoven fabric are shifted, resulting in poor appearance. For this reason, it is preferable that the nonwoven fabric to be folded is not bilaterally symmetrical from the center of the folded portion, and one dimension is increased or decreased.

  Next, a method for manufacturing the solar cell module 50 according to the first embodiment will be described based on specific examples.

  Hereinafter, the laminated structure in the vicinity of the output tab 11 and the extraction tab 31 according to the first embodiment will be described in detail.

(Example 1)
In Example 1, a sample of the solar cell module was manufactured according to the method of manufacturing the solar cell module 50 of Embodiment 1 described above. The main steps were performed as follows. As the translucent substrate 1, a white plate glass having an outer dimension of 1700 mm × 1000 mm and a thickness of 3.2 mm was prepared.

  As an overall lamination process of the solar cell module 50, an EVA resin sheet is prepared as a light receiving surface sealing layer sheet 2s for forming the light receiving surface sealing layer 2 which is in contact with the light transmitting substrate 1, and a solar cell The string in which the cells 3 were connected in series by the inter-cell tabs 4, the back surface sealing layer sheet 5s, and the back sheet 6 were laminated to form a laminate.

In addition, in the region X in FIG. 2, that is, around the S2 upper tab 22b of the horizontal tab 22 between S2 and S3 and around the end of the design sheet 74, the components were laminated as follows. In order to secure the insulation between the output tab 11 and the extraction tab 31 and the photovoltaic cell 3 that are soldered to the string and for extracting output, the first tab having an outer dimension of 100 mm × 100 mm and a thickness of 0.04 mm is used. The EVA sheet as the intermediate sealing layer sheet 71s and the PET sheet as the insulating sheet 72 having the outer dimensions of 100 mm × 100 mm and the thickness of 0.05 mm are formed with the output tab 11, the extraction tab 31, the solar cell 3, Was inserted in between.

  Then, the EVA sheet as the second intermediate sealing layer sheet 73 s having an outer size of 120 mm × 120 mm and a thickness of 0.4 mm, which is larger than the PET sheet as the insulating sheet 72, is attached to the left and right sides of the PET sheet of the insulating sheet 72. The layers were stacked so as not to protrude above the uppermost solar cell 3 of the string S2. Further, a nonwoven fabric sheet made of PET, which is a design sheet 74 for securing the design property, a back sealing layer sheet 5s and a back sheet 6 were further laminated thereon. That is, in Example 1, as shown in FIG. 8, the second intermediate sealing layer sheet 73s includes all the regions where the insulating sheet 72 and the design sheet 74 face each other.

  In addition, in the area Y1 in FIG. 2, that is, around the S4 upper tab 24b of the horizontal tab 24 between S4 and S5, and around the end of the design sheet 74, on the EVA resin sheet of the light receiving surface sealing layer sheet 2s, The inter-cell tab 4, the PET nonwoven fabric sheet 74 serving as the design sheet 74, the back surface sealing layer sheet 5s, and the back sheet 6 were laminated in this order.

Therefore, outside the solar cell 3 corresponding to the region Y1, there is a portion where the inter-cell tab 4 for electrically connecting the solar cell 3 is in contact with the nonwoven sheet made of PET as the design sheet 74 .

  Then, a laminate of the solar cell module of Example 1 was obtained by performing a laminating process on the formed body manufactured as described above. The lamination conditions were as follows: evacuation was performed at 160 ° C. for 5 minutes, press time was set to 5 minutes, and pressure during press was set to 50 kPa or 100 kPa.

(Example 2)
FIG. 16 is a schematic diagram of the laminate in Example 2 seen through from the back surface side. FIG. 17 is a cross-sectional view of a main part, which is a peripheral portion of the S2 upper tab of the horizontal tab between S2 and S3 of the laminate in Example 2, and schematically shows a laminated configuration around an end portion of the design sheet. That is, FIG. 17 is a cross-sectional view of a main part of a portion corresponding to the region X in FIG. FIG. 18 is a main part cross-sectional view schematically showing a configuration around an S4 upper tab of the horizontal tab between S4 and S5 of the laminate in Example 2, and showing a configuration around an end of the design sheet. That is, FIG. 18 is a cross-sectional view of a main part of a portion corresponding to the region Y2 in FIG.

  In Example 2, instead of the design sheet 74 made of a PET non-woven fabric sheet, a design sheet 74a made of a solid PET sheet which is not a non-woven fabric was used. Also, outside the solar cells 3 corresponding to the region Y2, as shown in FIG. 18, the surface between the inter-cell tabs 4 and the design sheet 74a made of a solid PET sheet which is not a non-woven fabric is made of EVA. The third intermediate sealing layer sheet 75s was inserted. Thereby, after the lamination process, the third intermediate sealing layer made of EVA is formed between the inter-cell tab 4 and the design sheet 74a, and the structure in which the inter-cell tab 4 and the design sheet 74a are not in contact with each other is obtained. A sample of the solar cell module of Example 2 was obtained. That is, in the second embodiment, the second intermediate sealing layer sheet 73s includes the entire region where the insulating sheet 72 and the design sheet 74a face each other.

(Example 3)
In the third embodiment, an EVA sheet as a first intermediate sealing layer sheet 71 s having the same size as the insulating sheet 72 is bonded and integrated on one surface of a PET sheet as the insulating sheet 72. Except for the above, a solar cell module sample of Example 3 was obtained in the same manner as Example 1. That is, in the third embodiment, the second intermediate sealing layer sheet 73s includes all the regions where the insulating sheet 72 and the design sheet 74 face each other.

Therefore, outside the solar cell 3 corresponding to the region Y1, there is a portion where the inter-cell tab 4 for electrically connecting the solar cell 3 is in contact with the nonwoven sheet made of PET as the design sheet 74 .

(Example 4)
In Example 4, the EVA sheet as the first intermediate sealing layer sheet 71 s was previously bonded to one surface of the PET sheet as the insulating sheet 72, and the same as the insulating sheet 72 on the other surface of the PET sheet as the insulating sheet 72. A sample of the solar cell module of Example 4 was prepared in the same manner as in Example 1 except that an EVA sheet, which is a second intermediate sealing layer sheet 73s having a size, was previously bonded and integrated. Obtained. That is, in the fourth embodiment, the second intermediate sealing layer sheet 73s includes all the regions where the insulating sheet 72 and the design sheet 74 face each other. In Example 4, an EVA sheet serving as the first intermediate sealing layer sheet 71s, an EVA sheet serving as the second intermediate sealing layer sheet 73s, and an insulating sheet 72 which were previously bonded and used were used. Since the arrangement shown in FIG. 14 cannot be performed, the EVA sheet serving as the second intermediate sealing layer sheet 73s is arranged on the insulating sheet 72 in FIG.

Therefore, outside the solar cell 3 corresponding to the region Y1, there is a portion where the inter-cell tab 4 for electrically connecting the solar cell 3 is in contact with the nonwoven sheet made of PET as the design sheet 74 .

(Comparative Example 1)
FIG. 19 is a conceptual diagram schematically illustrating a stacked configuration around the S2 upper tab of the horizontal tab between S2 and S3 of the laminated body in Comparative Example 1, and around the end of the design sheet. That is, FIG. 19 shows a conceptual diagram corresponding to FIG. FIG. 20 is a conceptual diagram schematically showing the configuration around the S4 upper tab of the horizontal tab between S4 and S5 of the laminate in Comparative Example 1, and around the end of the design sheet. That is, FIG. 20 shows a conceptual diagram corresponding to FIG.

  In Comparative Example 1, in the region X in FIG. 2, instead of the EVA sheet as the second intermediate sealing layer sheet 73 s which is larger than the PET sheet as the insulating sheet 72, the area is smaller than the PET sheet as the insulating sheet 72. The second intermediate sealing layer sheet 73 s having an outer shape of 50 mm × 20 mm and a thickness of 0.4 mm is formed so that the PET sheet of the insulating sheet 72 protrudes right and left and above the uppermost solar cell 3 of the string S2. Laminated. Except for this, in the same manner as in Example 1, a sample of the solar cell module of Comparative Example 1 was obtained. That is, in Comparative Example 1, as shown in FIG. 19, the second intermediate sealing layer sheet 73s does not include all the regions where the insulating sheet 72 and the design sheet 74 face each other.

Therefore, outside the solar cell 3 corresponding to the region Y1, there is a portion where the inter-cell tab 4 for electrically connecting the solar cell 3 is in contact with the nonwoven sheet made of PET as the design sheet 74 .

(Comparative Example 2)
FIG. 21 is a conceptual diagram schematically showing a layered structure around the S2 upper side tab of the horizontal tab between S2 and S3 of the laminate in Comparative Example 2, and around the end of the design sheet. That is, FIG. 21 shows a conceptual diagram corresponding to FIG. FIG. 22 is a conceptual diagram schematically illustrating a configuration around the S4 upper tab of the horizontal tab between S4 and S5 of the laminate in Comparative Example 2, and around the end of the design sheet. That is, FIG. 22 shows a conceptual diagram corresponding to FIG.

  In Comparative Example 2, a sample of the solar cell module of Comparative Example 2 was obtained in the same manner as in Example 1 except that the EVA sheet serving as the second intermediate sealing layer sheet 73s was not provided in the region X in FIG. Was. That is, in Comparative Example 2, as shown in FIG. 21, the second intermediate sealing layer sheet 73s does not exist in the entire region where the insulating sheet 72 and the design sheet 74 face each other.

(Comparative Example 3)
FIG. 23 is a conceptual diagram schematically illustrating a stacked configuration around an end portion of an S2 upper side tab of a horizontal tab between S2 and S3 of a laminate in Comparative Example 3, and around an end portion of a design sheet. That is, FIG. 23 is a conceptual diagram corresponding to FIG. 17 of the second embodiment. FIG. 24 is a conceptual diagram schematically showing the configuration around the S4 upper tab of the horizontal tab between S4 and S5 of the laminate in Comparative Example 3, and around the end of the design sheet. That is, FIG. 24 is a conceptual diagram corresponding to FIG. 18 of the second embodiment.

  In Comparative Example 3, on the surface outside the solar cell 3 corresponding to the region Y2 in FIG. 16, the third surface made of EVA is provided on the surface where the inter-cell tab 4 and the design sheet 74a made of a solid PET sheet, which is not a nonwoven fabric, face each other. A solar cell module sample of Comparative Example 3 was obtained in the same manner as in Example 2, except that the intermediate sealing layer sheet 75s was not inserted. That is, in the comparative example 3, the inter-cell tab 4 and the design sheet 74a made of a solid PET sheet which is not a nonwoven fabric are not formed with the third intermediate sealing layer 75 made of EVA in the sample of the example 2. A sample of a solar cell module having a structure in contact with was obtained. Therefore, in Comparative Example 3, the second intermediate sealing layer sheet 73s includes the entire area where the insulating sheet 72 and the design sheet 74a face each other.

  Thereafter, the samples of Examples 1 to 4 and Comparative Examples 1 to 3 were subjected to a 100-hour high-temperature and high-humidity (Damp-Heat: DH) test to determine whether bubbles were generated assuming an outdoor environment. A confirmation test was performed. Then, after the lamination treatment and after the DH test, the sample was visually observed from the light-transmitting substrate 1 side, and the presence or absence of bubbles was evaluated. FIG. 25 shows the result. FIG. 25 is a diagram illustrating evaluation results of the presence or absence of bubbles in the samples of the example and the comparative example.

  FIG. 26 is a schematic view showing a bubble generation region α where a bubble is generated in a portion of the sample of Comparative Example 1 where the second intermediate sealing layer sheet 73s is not covered. FIG. 27 is a schematic view showing a bubble generation region α in which a bubble is generated in a portion of the sample of Comparative Example 2 where the second intermediate sealing layer sheet 73s is not covered. FIG. 28 is a schematic diagram showing a bubble generation region α where a bubble is generated in a portion of the sample of Comparative Example 3 where the second intermediate sealing layer sheet 73s is not covered. 26 to 28 show a state in which the sample solar cell module is seen through from the back side.

  As shown in FIG. 25, in the samples of Examples 1, 2, 3, and 4, neither generation of air bubbles nor defective appearance was confirmed after any of the two types of lamination and after the DH test.

  However, the sample of the second embodiment is more preferable because the sample used in the solar cell module has more components than the sample of the first embodiment and is expensive in terms of workability and cost.

  On the other hand, in the samples of Comparative Example 1 and Comparative Example 2, in the confirmation after the two kinds of laminating treatment, in the region X, the portion where the second intermediate sealing layer sheet 73s made of EVA for the purpose of suppressing bubbles was not covered. As a result, air bubbles were generated on the surface of the design sheet 74 made of a nonwoven fabric, and poor appearance occurred. That is, in the samples of Comparative Example 1 and Comparative Example 2, a portion of the surface of the design sheet 74 not filled with EVA as a sealing material occurs, and a portion of EVA not filled in the solar cell module occurs. It was confirmed that. However, in the samples of Comparative Example 1 and Comparative Example 2, no expansion of bubbles was observed after the DH test. However, the generation of air bubbles is a problem from the viewpoint of appearance both after the lamination and after the DH test.

  In the sample of Comparative Example 3, no bubbles were found in the confirmation after the two kinds of lamination. However, the sample of Comparative Example 3 was not covered with the second intermediate sealing layer sheet 73s made of EVA for the purpose of suppressing bubbles in the region Y2 after the DH test, and was not a non-woven fabric with the inter-cell tab 4 and the non-woven fabric. Bubbles were generated from the contact portion with the design sheet 74a made of a PET sheet of the material, resulting in poor appearance.

  From these facts, in the region X, by providing the second intermediate sealing layer 73 made of EVA for the purpose of suppressing bubbles on the surface of the design sheet 74 made of non-woven fabric, the design sheet 74 made of PET and PET are formed. It can be said that the occurrence of bubbles between the design sheet 74 made of PET and the insulating sheet 72 made of PET can be suppressed by preventing the contact with the insulating sheet 72. The provision of the second intermediate sealing layer 73 allows EVA to penetrate into the voids of the nonwoven fabric of the design sheet 74, and the large specific surface area of the design sheet 74 allows the design sheet 74 to communicate with the EVA. Adhesion can be enhanced, and generation of air bubbles on the surface of the design sheet 74 made of a nonwoven fabric can be suppressed.

  When the design sheet 74a made of a solid PET sheet made of a non-woven fabric is used in the region Y2, the inter-cell tab 4 and the design sheet 74a made of a solid PET sheet made of a non-woven fabric face each other. By inserting the third intermediate sealing layer sheet 75s made of EVA, the contact between the inter-cell tab 4 and the design sheet 74a is prevented, and the generation of air bubbles between the inter-cell tab 4 and the design sheet 74a is prevented. It can be said that generation can be suppressed.

  Therefore, according to the manufacturing methods of Examples 1, 2, 3, and 4, no bubbles are generated during production, and no bubbles are generated even when installed outdoors after shipment. It can be said that a solar cell module capable of suppressing deterioration in appearance quality due to aging is obtained.

  The configurations described in the above embodiments are merely examples of the contents of the present invention, and can be combined with other known technologies, and can be combined with other known technologies without departing from the gist of the present invention. Parts can be omitted or changed.

  The solar cell module 50 described in the above embodiment has a trapezoidal shape in which one side of the outer shape is an oblique side by changing the number of solar cells 3 electrically connected in series in series for each string. Is useful when the design sheet 74 is disposed between the holding frame attached to the oblique side and the solar cell 3. By providing the design sheet with 74, the solar cell module 50 has an effect that the design property is not impaired even if the solar cell module has a trapezoidal shape.

  Further, the solar cell module 50 shown in the above embodiment is configured such that one side of the outer shape becomes an oblique side by changing the number of solar cells 3 electrically connected in series in series for each string. In a solar cell module having a trapezoidal shape, it is useful for a solar cell module configured by arranging strings in odd rows. The solar cell module 50 has a configuration in which the strings are arranged in odd-numbered rows to form a solar cell module, so that the negative electrode side terminal box 51 is arranged at one end in the connection direction of the solar cells 3 in the string, and the negative electrode terminal box is arranged at the other end. The side output cable 52 can be arranged, and there is an effect that electrical connection between the solar cell modules arranged adjacent to each other is facilitated. In this case, the negative terminal box 51 and the negative output cable 52 at the other end may be arranged at a certain distance in the connection direction of the solar cells 3 in the string. Further, by making the number of strings arranged odd, it is necessary to arrange the terminal box also on the oblique side of the trapezoidal shape of the solar cell module. Also in this case, the solar cell module 50 has an effect that generation of bubbles can be suppressed even if the terminal box is arranged on the oblique side provided with the design sheet 74.

  Further, the solar cell module 50 shown in the above embodiment is configured such that one side of the outer shape becomes an oblique side by changing the number of solar cells 3 electrically connected in series in series for each string. It is useful for a solar cell module having a trapezoidal shape and having an output tab and an extraction tab on the oblique side. For example, when the string S1 described above is shaded and sunlight does not enter and the string S1 does not generate power, an extraction tab is required on the oblique side to bypass the string S1. In this case, the string S1 cannot be bypassed by an extraction tab arranged only on the other side other than the oblique side in the connection direction of the solar cells 3 in the string. By taking out the removal tab from the hypotenuse side, there is an effect that the string S1 can be bypassed when the string S1 connected to the hypotenuse output tab is shaded. That is, referring to FIG. 3, the string S <b> 1 cannot be bypassed by the extraction tab arranged only on the lower side of the trapezoidal shape in the figure. The solar cell module 50 has an effect that the string S1 connected to the output tab on the oblique side can bypass the shaded string S1 by extracting the extraction tab 31 from the oblique side.

  Further, the solar cell module 50 shown in the above embodiment is configured such that one side of the outer shape becomes an oblique side by changing the number of solar cells 3 electrically connected in series in series for each string. In a solar cell module having a trapezoidal shape, it is useful for a solar cell module in which an output tab and an extraction tab are taken out to the same terminal box on the oblique side. In order to bypass the string S1 connected to the output tab on the hypotenuse side, it is necessary to take out the output tab and the extraction tab to the same terminal box on the hypotenuse side. Here, in order to reduce the size of the terminal box, it is necessary to connect the output tab to the vicinity of the output tab, and there are places where the output tab overlaps with the horizontal tab, so insulation between the output tab and the horizontal tab is required become. In the solar cell module 50, the take-out positions of the output tab and the take-out tab on the oblique side can be brought close to each other by the insulating sheet, so that the terminal box can be downsized.

  REFERENCE SIGNS LIST 1 translucent substrate, 2 light-receiving surface sealing layer, 2 s light-receiving surface sealing layer sheet, 3 solar cells, 3 a light-receiving surface electrode, 3 b back electrode, 4 cell tab, 5 back sealing layer, 5 s back sealing Layer sheet, 6 back sheet, 6a, 6b removal hole, 11, 12 output tab, 21 S1-S2 horizontal tab, 22 S2-S3 horizontal tab, 22a S3 upper tab, 22b S2 upper tab, 22c S2-S3 connection Tab, 23 S3-S4 horizontal tab, 24 S4-S5 horizontal tab, 24a S5 upper tab, 24b S4 upper tab, 24c S4-S5 connection tab, 31, 32, 33 extraction tab, 41, 42, 43 bypass diode , 50 solar cell module, 51 negative terminal box, 52 negative output cable, 53 positive terminal box, 54 positive output cable, 71 first Intermediate sealing layer, 71s First intermediate sealing layer sheet, 72 insulating sheet, 73 Second intermediate sealing layer, 73s Second intermediate sealing layer sheet, 74 Design sheet, 75s Third intermediate sealing layer Sheet, α bubble generation area.

Claims (11)

A light-receiving surface side protection member disposed on the light-receiving surface side and having light transmissivity;
A back side protection member arranged on the back side facing the light receiving surface,
A solar cell string in which a plurality of solar cells are electrically connected in series by inter-cell tabs,
A lateral tab that electrically connects the plurality of solar cell strings to each other in series,
An output tab for taking output from the solar cell string to the outside of the back surface side protection member,
A plurality of types of tabs including the inter-cell tab, the horizontal tab, and the output tab,
A sealing layer made of resin and sandwiching the solar cell string between the light receiving surface side protection member and the back surface side protection member,
An insulating sheet that insulates at least a part between the tabs of the plurality of types of tabs ,
And the design sheet covering the outer periphery side of the front Symbol solar cell string,
A first intermediate sealing layer disposed between the lateral tab and the insulating sheet to bring the lateral tab and the insulating sheet into a non-contact state;
A second intermediate sealing layer disposed between the insulating sheet and the design sheet to bring the insulating sheet and the design sheet into a non-contact state;
A solar cell module comprising:   The insulating sheet insulates between the output tab and the horizontal tab,
  The solar cell module according to claim 1, wherein: That the design sheet is a nonwoven fabric,
The solar cell module according to claim 1 or 2, characterized in. The design sheet is made of solid material,
A third intermediate sealing layer disposed between the inter-cell tab and the design sheet to make the inter-cell tab and the design sheet in a non-contact state,
The solar cell module according to claim 1 or 2, characterized in. A light-transmitting light-receiving surface-side protection member, a first sealing layer sheet, and a solar cell string in which a plurality of solar cells are electrically connected in series by inter-cell tabs are electrically connected by horizontal tabs The obtained solar cell array, the first intermediate sealing layer sheet, the insulating sheet, the second intermediate sealing layer sheet, the design sheet, the second sealing layer sheet, the back surface side protection member, A laminating step of sequentially laminating to form a laminate,
A sealing step of heating and pressing the laminate to seal the solar cell string between the light receiving surface side protection member and the back surface side protection member;
Including
The first intermediate sealing layer sheet is disposed between the horizontal tab and the insulating sheet,
Wherein the second intermediate sealing layer sheet is disposed between the insulating sheet and the design sheet,
A method for manufacturing a solar cell module, comprising:   In the laminating step,
  An output tab for taking output from the solar cell string to the outside of the back surface side protection member is connected to the horizontal tab,
  The insulating sheet is disposed at a position to insulate at least a part between tabs of a plurality of types of tabs including the inter-cell tab, the horizontal tab, and the output tab.
  The method for manufacturing a solar cell module according to claim 5, wherein:   The insulating sheet is disposed at a position to insulate between the output tab and the horizontal tab,
  The method for manufacturing a solar cell module according to claim 6, wherein: That the design sheet is a nonwoven fabric,
The method for manufacturing a solar cell module according to claim 5, wherein: The design sheet is made of solid material,
In the laminating step, disposing a third intermediate sealing layer between the inter-cell tab and the design sheet,
The method for manufacturing a solar cell module according to claim 5, wherein: Using a sheet in which the first intermediate sealing layer sheet is bonded to and integrated with one surface of the insulating sheet;
Method of manufacturing a solar cell module according to any one of claims 5 to 9, characterized in. Using a sheet in which the first intermediate sealing layer sheet is adhered to one surface of the insulating sheet, and the second intermediate sealing layer sheet is adhered to the other surface of the insulating sheet to be integrated;
Method of manufacturing a solar cell module according to any one of claims 5 to 9, characterized in.

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