JP2015002318A - Solar cell module and manufacturing method thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module which improves module conversion efficiency by attaining downsizing of the solar cell module, achieves reduction of costs and reduction of weight and improves appearance design, and a manufacturing method thereof.SOLUTION: A solar cell module 50 comprises: a solar cell string formed by connecting a plurality of solar cells 1 via a tab line 5; a translucent substrate 2; a rear side protection material with which a plurality of solar cell strings are disposed between the rear side protection material and the translucent substrate 2; horizontal tab lines 6a and 6b connecting in series a plurality of solar cell strings disposed between the translucent substrate 2 and the rear side protection material; lead wires 7a and 7b for extracting power from the plurality of solar cell strings connected in series; and an encapsulation material 3 for encapsulating a plurality of solar cell strings between the translucent substrate 2 and the rear side protection material. The horizontal tab lines 6a and 6b and the lead wires 7a and 7b are disposed on a side surface of the translucent substrate 2.

Description

  The present invention relates to a solar cell module in which a plurality of solar cells are sealed between a translucent insulating substrate and a back cover material, and a method for manufacturing the solar cell module.

  A conventional manufacturing method and structure of a solar cell module is described in Patent Document 1.

  In a conventional solar cell module, a plurality of solar cells are electrically connected to each other using a ribbon (ribbon wire) of a conductor made of copper foil or the like as a tab wire. The plurality of solar cells are sealed with a translucent substrate made of plastic or glass, a sealing material made of EVA (Ethylene Vinyl Acetate) or the like, and a back surface protective material.

  Moreover, the several photovoltaic cell electrically connected in series with the tab wire forms the photovoltaic cell string as a unit unit. At both ends of the string, a horizontal tab line for electrically connecting adjacent solar cell strings and a lead line for outputting generated power to the terminal box are connected. These are wired around the solar cells forming the solar cell string. An aluminum frame is bonded and attached to the end portion of the light-transmitting substrate in which the solar cell string is sealed using a moisture-resistant sealing material.

  As described above, solar cells are connected in series with tab wires, and solar cells are connected to solar cells so that a predetermined output (for example, 250 W) as a solar cell module is generated via horizontal tab wires and lead wires. A battery module is configured.

JP 2010-161178 A (FIG. 5-3)

  In the conventional solar cell module wiring method, since the horizontal tab lines and the lead wires are arranged in parallel adjacent to the solar cells forming the solar cell string, the solar cell is on the surface of the solar cell module. In addition to the region where a plurality of cells are arranged, there is a region that does not contribute to the power generation occupied by the horizontal tab lines and lead wires, and the size of the solar cell module becomes larger than necessary. As a result, the module power generation efficiency of the solar cell module is lowered, and a large member such as glass is required, resulting in an increase in cost and an increase in weight. It was.

  In addition, when the horizontal tab line is arranged on the same plane as the solar battery cell, there is a problem that the color and the member shape are not uniform and the design property is impaired.

  The present invention has been made in view of the above, and it is possible to reduce the size of the solar cell module, improve the module conversion efficiency, realize cost reduction and weight reduction, and further improve the appearance design. An object is to obtain an enhanced solar cell module and a method for manufacturing the same.

  In order to solve the above-described problems and achieve the object, the present invention includes a solar cell string formed by connecting a plurality of solar cells with tab wires, a translucent substrate, and a translucent substrate. Back surface protective material in which a plurality of solar cell strings are arranged, horizontal tab lines electrically connecting the plurality of solar cell strings in series, and a plurality of solar cell strings electrically connected in series by the horizontal tab lines A solar cell module including a solar cell panel having a lead wire for taking out electric power from, and a sealing material for sealing a plurality of solar cell strings between the translucent substrate and the back surface protective material, The tab line and the lead line are arranged on the side surface of the translucent substrate.

  According to the present invention, the module conversion efficiency can be improved, and the solar cell module can be reduced in size and weight and cost can be reduced.

FIG. 1 is a diagram showing a configuration of a first embodiment of a solar cell module according to the present invention. FIG. 2 is a diagram illustrating a configuration of a solar battery cell used in the solar battery module according to the first embodiment. FIG. 3 is a schematic view of one side surface of the short side of the solar cell module showing the connection between the solar cell strings. FIG. 4 is a schematic view of the other side surface of the short side of the solar cell module. FIG. 5 is a circuit diagram showing an electrical connection state between solar cell strings. FIG. 6 is a partial cross-sectional view showing horizontal tab lines and lead lines connected to the solar cell string. FIG. 7 is a schematic view of a laminator for sealing the solar cell module. FIG. 8 is a schematic diagram showing the configuration of the second embodiment of the solar cell module according to the present invention. FIG. 9 is a schematic cross-sectional view showing the configuration of the solar cell module according to the second embodiment of the present invention.

  Embodiments of a solar cell module and a manufacturing method thereof according to the present invention will be described below in detail with reference to the drawings. Note that the present invention is not limited to the embodiments. Moreover, about the magnitude | size of each member in a figure, in order to make the content of invention easy to understand, each part is expanded and shown suitably, without being restricted to an actual ratio.

Embodiment 1 FIG.
FIG. 1 is a diagram showing a configuration of a first embodiment of a solar cell module according to the present invention. The solar cell module 50 according to the first embodiment includes a plurality of solar cells 1. The solar battery cell 1 is a crystalline silicon solar battery made of single crystal silicon, polycrystalline silicon, or the like, or substantially intrinsic amorphous silicon between a single crystal silicon substrate and an amorphous silicon thin film layer. A heterojunction solar cell with a thin film layer interposed therebetween is used.

  Here, the solar cell 1 is assumed to be a heterojunction solar cell that can be expected to have high output.

  The solar cell module 50 according to the first embodiment includes a solar cell panel 40 configured by sealing the solar cell string 10 with a translucent substrate, a sealing material, and a back surface protective material, and an outer periphery of the solar cell panel 40. And an aluminum frame 9 which is bonded and incorporated in the part via a sealant 8.

  The solar cell string 10 is formed by electrically connecting each of the plurality of solar cells 1 in series via the tab wire 5. Tab wire 5 is formed of copper foil or the like. One end of the tab wire 5 is connected to the current collecting electrode on the front surface side of the predetermined solar battery cell 1, and the other end of the tab wire 5 is connected to the current collecting electrode on the back surface side of another adjacent solar battery cell 1. Is connected.

  FIG. 2 is a diagram illustrating a configuration of a solar battery cell used in the solar battery module according to the first embodiment. The solar cell 1 includes a crystalline silicon substrate 11, an intrinsic amorphous silicon thin film 12, a p-type silicon thin film 13, a transparent conductive film 14, an intrinsic amorphous silicon thin film 15, an n-type silicon thin film 16, It has a transparent conductive film 17 and thin linear collector electrodes 18 and 19. The solar cell 1 includes a transparent conductive film 14, a p-type silicon thin film 13, an intrinsic amorphous silicon thin film 12, a crystalline silicon substrate 11, and an intrinsic amorphous silicon thin film in order from the surface (light receiving surface) side. 15. A laminated structure in which the n-type silicon thin film 16 and the transparent conductive film 17 are overlapped. The fine linear collector electrode 18 is arranged on the front surface side, and the fine linear collector electrode 19 is arranged on the back surface side.

  The crystalline silicon substrate 11 is a single conductivity type single crystal silicon substrate, and is preferably an n-type single crystal silicon substrate. In addition, the crystalline silicon substrate 11 is preferably cut out so that the surface (upward surface in FIG. 2) that serves as the light incident surface of the solar battery cell 1 is the (100) surface. By making the light incident surface of the solar cell 1 as a (100) plane, the surface of the single crystal silicon substrate is easily etched by anisotropic etching with different etching rates between the (100) plane and the (111) plane. In addition, a substantially mountain-shaped texture forming process can be performed.

  The intrinsic amorphous silicon-based thin films 12 and 15 may contain impurities mixed in the film formation process as long as they do not affect the power generation characteristics. That is, even if it is not theoretically intrinsic due to the mixing of impurities, it can be regarded as intrinsic if it is mixed so as not to affect the power generation characteristics. The intrinsic amorphous silicon thin film 12 and the intrinsic amorphous silicon thin film 15 are hydrogenated amorphous silicon thin films (a-Si (i): H) formed of silicon and hydrogen. Is desirable. It is desirable to use a p-type amorphous silicon thin film (a-Si (p)) for the p-type silicon thin film 13. As for the n-type silicon thin film 16, it is desirable to use an n-type amorphous silicon thin film (a-Si (n)). On the back surface of the solar battery cell 1, a BSF (Back Surface Field) region is formed by the intrinsic amorphous silicon thin film 15 and the n-type silicon thin film 16.

  The transparent conductive film 14 and the transparent conductive film 17 are formed on the p-type silicon-based thin film 13 or the n-type silicon-based thin film 15 using a conductive oxide mainly composed of indium oxide.

  On the transparent conductive film 14 and the transparent conductive film 17, a fine linear collector electrode 18 or a fine linear collector electrode 19 is formed. The thin wire collecting electrode 18 and the thin wire collecting electrode 19 can be formed by a known method such as ink jet, screen printing, spray coating or the like.

  The thin wire collecting electrode 18 and the thin wire collecting electrode 19 are obtained by screen-printing a paste (conductive paste) obtained by mixing metal conductive particles with a resin binder, and then solidifying the printed conductive paste by heat treatment. Is preferably formed. The thin wire collecting electrode 18 and the thin wire collecting electrode 19 are composed of a bus bar portion and finger portions, and the tab wire 5 is connected to the bus bar portion.

  In the solar cell module 50 according to the present embodiment shown in FIG. 1, ten solar cells 1 are electrically connected in series by tab wires 5 to constitute a solar cell string 10. In the present embodiment, six more solar cell strings 10 are electrically connected in series. Therefore, the solar cell module 50 according to the present embodiment is configured to include 60 solar cells 1. In addition, even if the number of series increases / decreases (namely, even if the number of the photovoltaic cells 1 which comprise the solar cell string 10 increases / decreases), this invention is applicable.

  The solar battery string 10 is arranged so that the p-type silicon thin film 13 side of the solar battery cell 1 faces the light receiving surface, and the adjacent solar battery cells 1 are connected by the tab wire 5. Therefore, the fine linear current collecting electrode 18 on the front side becomes a positive electrode, and the fine linear current collecting electrode 19 on the back side becomes a negative electrode.

  Next, the connection between the solar cell strings 10 will be described in detail with reference to FIGS. FIG. 3 is a schematic view of one side surface of the short side of the solar cell module showing the connection between the solar cell strings. FIG. 4 is a schematic view of the other side surface of the short side of the solar cell module. 3 and 4 are perspective views from the back surface side of the solar cell module 50. For the sake of explanation, the aluminum frame 9, the back surface protection material 4, and the sealing material 3 are the ends of the translucent substrate 2. The illustration of the portion in contact with the part is omitted as appropriate. FIG. 5 is a circuit diagram showing an electrical connection state between solar cell strings. FIG. 6 is a partial cross-sectional view showing horizontal tab lines and lead lines connected to the solar cell string.

  The solar cell panel 40 is configured by sealing the solar cell string 10 with the translucent substrate 2, the sealing material 3, and the back surface protective material 4.

  Conventionally, the horizontal tab lines and the lead lines are wired around the solar cells, but in the present embodiment, the horizontal tab lines 6a to 6e and the lead lines 7a and 7b are connected to the light-transmitting substrate 2. It is arranged on the side. That is, the horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b are arranged in parallel on one end side surface of the translucent substrate 2. Each of the horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b is fixed with an adhesive 21 on the side surface portion of the translucent substrate 2. Similarly, the horizontal tab lines 6c to 6e are connected to the side of the solar cell string 10 opposite to the side where the lead lines 7a and 7b are arranged, and to the side surface opposite to the translucent substrate 2. It is fixed with adhesive.

  The terminal box 24 is attached to the back surface protective material 4. The terminal box 24 accommodates the bypass diodes 20a to 20c, the positive terminal 25, and the negative terminal 26.

  The lead lines 7a and 7b are configured as output lead lines to the terminal box 24 side. In the present embodiment, the lead wire 7a is used for the positive electrode, and the lead wire 7b is used for the negative electrode.

  The lead wire 7 a is taken out from the back surface protective material 4 and extended to the terminal box 24. In FIG. 3, the lead-out line 7a is connected to the tab line 5 on the surface side of the solar cell string 10 located at the left end in the figure. The lead wire 7 a is connected to the bypass diode 20 a and the positive electrode terminal 25 in the terminal box 24.

  The lead wire 7 b is taken out from the back surface protective material 4 and extended to the terminal box 24. In FIG. 3, the lead-out line 7b is connected to the tab line 5 on the back surface side of the solar cell string 10 located at the right end in the drawing. The lead wire 7 b is connected to the bypass diode 20 c and the negative electrode terminal 26 in the terminal box 24.

  The horizontal tab lines 6a to 6e connect adjacent solar cell strings 10 in series. The horizontal tab lines 6a to 6e connect the tab line 5 on the front side of the solar battery cell 1 located at the end of the string and the tab line 5 on the back surface side of the adjacent solar battery cell 1. Further, the horizontal tab lines 6a and 6b are taken out from the back surface protective material 4 in the same manner as the lead lines 7a and 7b for connection to the bypass diodes 20a to 20c. One end of the horizontal tab wire 6 a extends into the terminal box 24 and is connected to the bypass diodes 20 a and 20 b in the terminal box 24. Further, one end of the horizontal tab wire 6 b is extended into the terminal box 24 and connected to the bypass diodes 20 b and 20 c in the terminal box 24.

  In the present embodiment, a white plate tempered glass having a thickness of 3.2 mm, which is generally used for a cover glass of a solar cell module, is used for the translucent substrate 2. The horizontal tab lines 6a and 6b and the lead lines 7a and 7b are metal foil plates mainly made of copper having a width of 1.5 mm and a thickness of about 1 mm, respectively, in accordance with the thickness of the translucent substrate 2 of 3.2 mm. Is formed.

  Since the cross-sectional area of the horizontal tab wire used in the conventional solar cell module is 5 mm wide × 300 μm thick, this embodiment uses a metal foil plate having a width of 1.5 mm for the horizontal tab wires 6a and 6b. Then, in order to obtain a resistance value equal to or less than the conventional resistance value, the thickness of the metal foil plate may be set to 1 mm. If this condition is satisfied, there is no problem with the loss due to resistance.

  The horizontal tab lines 6c to 6e are formed of a metal foil plate mainly composed of copper having a width of 3 mm and a thickness of approximately 1 mm in accordance with the thickness of the translucent substrate 2 of 3.2 mm.

  In the present embodiment, when insulation between the horizontal tab lines, between the lead lines, or between the horizontal tab line and the lead lines is necessary, the wiring itself may be subjected to a laminate film treatment, You may use the horizontal tab wire 6 to which the insulation coating was given. In the present embodiment, the horizontal tab wire 6 and the lead wire 7 provided with the insulating coating 22 are used. The insulating coating 22 is preferably made of a material that does not melt at the lamination process temperature. For example, a polyimide resin, a fluorine resin, a silicone resin, or a rubber material can be used.

  As shown in FIG. 6, the horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b arranged in parallel on the end side surface of the translucent substrate 2 are formed of the solar cell string 10 with the sealing material 3 and the back surface protective material 4. When laminating, the sealing material 3 and the back surface protective material 4 are entirely covered and sealed.

  Similarly, on the side surface on the opposite side of the translucent substrate 2, the horizontal tab lines 6 c to 6 e are separated from the sealing material 3 when the solar cell string 10 is laminated with the sealing material 3 and the back surface protection material 4. The entire structure is covered and sealed with the back surface protective material 4.

  Thus, by covering and sealing the horizontal tab lines 6a to 6e and the lead lines 7a and 7b with the sealing material 3 and the back surface protective material 4 at the time of laminating, the horizontal tab lines 6a to 6e and the lead lines 7a, The weather resistance and moisture resistance of 7b can be obtained with performance comparable to that of conventional solar cell modules, and long-term outdoor use, which is one of the performances required for solar cell modules, is possible.

  Next, the lamination process which is one of the manufacturing processes of the solar cell module 50 concerning this Embodiment is demonstrated. FIG. 7 is a schematic view of a laminator for sealing the solar cell module. The laminator includes an upper casing 30 of the apparatus and a lower casing 31 of the apparatus. The upper casing 30 and the lower casing 31 are coupled with each other through an opening facing each other, and a sealed laminate chamber is configured inside the casing. The lower casing 31 is provided with a heater stage 32 that is flush with the upper surface of the lower casing 31. The upper casing 30 is provided with a rubber diaphragm 33 so as to face the heater stage 32. The upper casing 30 and the lower casing 31 are provided with an O-ring 34 around the opening in order to obtain hermeticity when combined.

  In manufacturing the solar cell module 50, first, the horizontal tab wires 6 a to 6 e and the lead wires 7 a and 7 b and the translucent substrate 2 are bonded with the adhesive 21. As the adhesive 21, it is possible to apply a general material and method for manufacturing a solar cell module. For example, a method of lowering the temperature after raising the temperature using a silicone resin can be applied. By adhering the horizontal tab lines 6a to 6e and the lead lines 7a and 7b and the translucent substrate 2, it is possible to prevent the wiring from being displaced in the subsequent process.

  Next, the unit in which the horizontal tab wires 6a to 6e and the lead wires 7a and 7b and the translucent substrate 2 are integrated, the sheet-like light-receiving surface side sealing material 3a, and the solar cell string 10 are stacked. Later, the tab wire 5 is bent toward the light receiving surface of the translucent substrate 2, and the tab wire 5 is soldered to the horizontal tab wires 6a to 6e and the lead wires 7a and 7b. By bending the tab wire 5 toward the light receiving surface of the translucent substrate 2, soldering to the horizontal tab wires 6a to 6e and the lead wires 7a and 7b is facilitated. Further, the horizontal tab lines 6a and 6b and the lead lines 7a and 7b are arranged in parallel on the side surfaces of the end of the translucent substrate 2, and the wiring does not overlap, so that soldering can be easily performed.

  Thereafter, the unit in which the horizontal tab wires 6a to 6e and the lead wires 7a and 7b and the translucent substrate 2 are integrated, the light receiving surface side sealing material 3a, and the solar cell string 10 are placed on the heater stage 32. The back surface side sealing material 3b and the back surface protection material 4 are stacked in this order. At this time, the back surface side sealing material 3b and the back surface protection material 4 at both ends in the solar cell string 10 direction where the horizontal tab wires 6a to 6e and the lead wires 7a and 7b are bonded to the light receiving surface side sealing material 3a The translucent substrate 2 having a thickness of 3.2 mm is larger than the translucent substrate 2. As an example, the surplus size is about 1 to 2 cm. Here, the surplus size is set to about 1 to 2 cm, but since the optimum surplus size is actually determined by the thickness of the translucent substrate 2 to be used and the size of other members, the back side sealing material 3b and the back side protection material The surplus size of 4 is not limited to the above specific numerical value.

  As described above, after the components are arranged on the heater stage 32, the upper casing 30 and the lower casing 31 of the apparatus are combined, and the laminate chamber is closed. Thereafter, the air in the laminate chamber is exhausted with a vacuum pump, and the pressure in the chamber is reduced. At this time, the heater stage 32 is heated to about 150 to 180 ° C. In this state, the diaphragm 33 presses the solar cell panel on the heater stage 32 in the decompressed laminate chamber. At this time, the light-receiving surface side sealing material 3a and the back surface side sealing material 3b are gelled and crosslinked to form the sealing material 3, thereby forming a sealing material layer of the solar cell module. Through this step, the solar battery cell 1 is sandwiched between the translucent substrate 2 and the back surface protective material 4 and sealed in the layer of the sealing material 3.

  By using a material slightly larger than the translucent substrate 2 for the back surface side sealing material 3b and the back surface protection material 4, the horizontal tab lines 6a to 6e and the lead lines 7a and 7b arranged on the side surface of the translucent substrate 2 are used. However, the whole structure is sealed with the sealing material 3 and the back surface protection material 4. Here, when the width and depth of the back surface side sealing material 3b and the back surface protection material 4 are increased by twice the thickness of the translucent substrate 2, they are disposed on the side surfaces of the translucent substrate 2 in the laminating step. Since the back surface side sealing material 3b and the back surface protection material 4 are bonded together so as to cover the horizontal tab wire 6 and the lead wire 7, the durability of the horizontal tab wire 6 and the lead wire 7 can be improved.

  In the solar cell module 50 according to the present embodiment, a structure in which the horizontal tab wires 6 a to 6 e and the lead wires 7 a and 7 b do not exist at all on the solar cell 1 is obtained. On the other hand, in the case of the conventional structure, since the lead wiring is provided on the back surface of the module to the horizontal tab, a convex shape is formed by the thickness of the horizontal tab and the lead wiring. Therefore, in the solar cell module 50 according to the present embodiment, the unevenness on the laminate surface on the upper surface of the cell is constant as compared with the conventional structure, compared with the conventional structure, and at this time, the effect of suppressing the generation of bubbles in the laminate There is.

  In addition, when the pressure is reduced, the back surface side sealing material 3b tries to adhere to the uneven part by exhausting the air near the boundary of the uneven part. A contact portion and a non-contact portion are generated between the material 3b and the concavo-convex shape, and a force is applied only to the contact portion until both are completely adhered. For this reason, if the surface has few irregularities (close to flat), the force locally applied to the contact portion can be reduced. Therefore, the solar cell module 50 according to the present embodiment is a solar cell due to stress concentration during decompression. There is an effect of preventing cell cracking, and an effect of improving the manufacturing yield can be obtained.

  When the back surface side sealing material 3b and the back surface protection material 4 have a width and depth that are twice or more the thickness of the light transmissive substrate 2 and larger than the light transmissive substrate 2, After the completion, the excess sealing material 3 and the back surface protection material 4 that remain beyond the side of the end portion of the translucent substrate 2 remain. About this, it cuts in the same surface as the surface of the translucent board | substrate 2. FIG. By cutting the excess sealing material 3 and the back surface protective material 4 after laminating, the ends of the sealing material 3 and the back surface protective material 4 can be made flat on the same surface as the surface of the translucent substrate 2. If the sealing material 3 and the back surface protective material 4 are cut before laminating, man-hours can be omitted and productivity can be improved. On the other hand, a part of the side surface of the translucent substrate 2 is exposed, or the sealing material 3 and The end portion of the back surface protective material 4 protrudes to the front surface side of the translucent substrate 2 and may be easily peeled off when the aluminum frame 9 is mounted, which may cause a decrease in weather resistance and moisture resistance. For this reason, it can be selected whether the sealing material 3 and the back surface protection material 4 are cut after lamination according to whether importance is attached to weather resistance and moisture resistance or productivity. In addition, whether the sealing material 3 and the back surface protective material 4 are cut after lamination or not is determined so that the cut surfaces of the sealing material 3 and the back surface protective material 4 are flat with respect to the surface of the translucent substrate 2. It can be judged by whether or not.

  By cutting on the same plane of the surface of the translucent substrate 2, it becomes possible to smoothly attach the aluminum frame 9 to be attached in a later process, and the side surface disposed on the side surface of the end of the translucent substrate 2. It is possible to obtain a structure in which the tab wires 6 a to 6 e and the lead wires 7 a and 7 b are sealed with the sealing material 3 and the back surface protective material 4.

  An aluminum frame 9 is attached to the end of the translucent substrate 2 to obtain strength as a module housing. The aluminum frame 9 is attached by bonding via a sealing material 8. If the sealing material 8 used at this time is made of a material having excellent moisture resistance (for example, butyl rubber), the internal horizontal tab wire is used. Further advantageous effects can be expected against the deterioration of electrode materials such as 6a to 6e and lead wires 7a and 7b. By mounting the aluminum frame 9, the lateral tab wires 6a to 6e and the lead wires 7a and 7b are covered with the aluminum frame 9, so that the aesthetic appearance of the solar cell module is improved.

  Finally, the lead wires 7a and 7b and the horizontal tab wires 6a and 6b are pulled out from the back surface protective material 4, connected to the terminal box 24, and the terminal box 24 is attached onto the back surface protective material 4, and the solar cell module of the present embodiment 50 is obtained.

  When the solar cell module according to the present embodiment and the conventional solar cell module in which the horizontal tab lines are arranged around the solar cells are configured with the same output value, the horizontal tab lines and the lead lines are compared. Space can be reduced, the module efficiency can be improved, the amount of material used can be reduced, and the product weight can be reduced.

  In the case of a module in which a solar cell string is composed of 10 solar cells, the length of the solar cell module could be reduced by 18 mm. While the module conversion efficiency of the conventional structure was 20%, in the present embodiment, the module conversion efficiency was 20.26%, which was improved by 1.3% of 20%. In other words, the module conversion efficiency increased by about 0.2 points.

  In addition, the weight can be reduced by about 100 g per module. Furthermore, assuming that the photovoltaic power generation facility has a capacity of 1000 sheets, when the solar cell module of the present embodiment is used, if the module width is about 833 mm, the area equivalent to about 15 square meters is reduced. I can expect.

Embodiment 2. FIG.
Embodiment 2 of the solar cell module according to the present invention will be described. FIG. 8 is a schematic diagram showing the configuration of the second embodiment of the solar cell module according to the present invention. FIG. 9 is a schematic cross-sectional view showing the configuration of the solar cell module according to the second embodiment of the present invention. In the first embodiment, the horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b are arranged in parallel on the end side surface of the translucent substrate 2. On the other hand, in the solar cell module 60 according to the second embodiment, as shown in FIGS. 8 and 9, the horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b are formed as a three-dimensional wiring. At this time, the resistance value of the conductor used for the horizontal tab lines 6a and 6b and the lead lines 7a and 7b disposed on the side surface of the end of the translucent substrate 2 can be further reduced. Since it is relatively easy to use a wide conductor, it is easy to reduce the wiring resistance at the conductors (lateral tab wires 6a and 6b and lead wires 7a and 7b) of the solar cell module 60, and the generated power Joule loss due to the wiring resistance can be easily reduced.

  As the translucent substrate 2 used in the second embodiment, a white plate tempered glass having a thickness of 3.2 mm which is general for a solar cell cover glass is used. The horizontal tab lines 6a and 6b and the lead lines 7a and 7b are metal foils mainly composed of copper having a width of 3.0 mm and a thickness of about 0.5 mm, respectively, in accordance with the thickness of the translucent substrate 2 of 3.2 mm. It is made of a plate.

  Since the cross-sectional area of the horizontal tab line used in the conventional solar cell module is 5 mm wide × 300 μm thick, this embodiment uses a metal foil plate having a width of 3.0 mm for the horizontal tab lines 6a and 6b. Then, in order to obtain a resistance value equal to or less than the conventional resistance value, the thickness of the metal foil plate may be set to 0.5 mm. If this condition is satisfied, there is no problem with the loss due to resistance.

  In the second embodiment, the width of the conductor can be increased compared to the first embodiment by arranging the horizontal tab lines 6a and 6b and the lead lines 7a and 7b so as to overlap with each other. Wiring on the side of the end is easier.

  The horizontal tab lines 6 a and 6 b and the lead lines 7 a and 7 b are fixed with an adhesive 21 on the side surface portion of the translucent substrate 2. In the second embodiment, the horizontal tab wires 6a and 6b are first fixed to the side surfaces of the end portion of the translucent substrate 2 with the adhesive 21, and then the lead wires 7a and 7b are bonded onto the horizontal tab wires 6a and 6b. Fix with 21. For example, when the solar cell module is manufactured, a unit in which the horizontal tab wires 6a and 6b are fixed to the side surface of the translucent substrate 2 with an adhesive 21 is used, and the horizontal tab wires 6a and 6b and the translucent substrate 2 are integrated. After stacking the unit, the sheet-shaped light receiving surface side sealing material 3a, and the solar cell string 10, the tab wire 5 is bent to the light receiving surface side of the translucent substrate 2 and soldered to the horizontal tab wires 6a and 6b. Then, the lead wires 7a and 7b are bonded to the horizontal tab lines 6a and 6b.

  In the present embodiment, it is preferable to use the one provided with the insulating coating 22 in advance in order to overlap the horizontal tab wires 6a and 6b and the lead wires 7a and 7b.

  [1] Back film (0.2 mm thickness), [2] Sealing material (0.5 mm thickness), [3] (Adhesive (0.1 mm thickness) + Insulation) Cover (0.2 mm thickness × 2)) × 2, [4] The horizontal tab line (0.5 mm thickness) and the lead line (0.5 mm thickness) overlap. Since the total thickness of [1] to [4] is simply 2.7 mm, the increase in the length of the solar cell panel on the side where the horizontal tab lines 6a and 6b and the lead lines 7a and 7b are arranged is The actual value is less than 4 mm. In the conventional structure in which the horizontal tab line and the lead line are arranged in parallel on the side of the solar battery cell, it is necessary to secure a space of 10 mm or more corresponding to two metal foil plates with a width of 5 mm on the side of the solar battery cell. In the structure of the present embodiment, the space saving effect can be obtained even if the lateral tab lines 6a and 6b and the lead lines 7a and 7b are made thicker than the above example in order to reduce the wiring resistance.

  The points other than the wiring locations of the horizontal tab lines 6a and 6b and the lead lines 7a and 7b are the same as in the first embodiment. According to the second embodiment, it is possible to suppress an increase in the resistance values of the horizontal tab lines 6a and 6b and the lead lines 7a and 7b. Further, the horizontal tab lines 6a and 6b can have the same width and thickness as the horizontal tab lines 6c to 6e arranged on the opposite side surface of the translucent substrate 2, and the manufacturing cost can be reduced by using a common material. Can be suppressed.

  Thus, according to the solar cell module concerning this invention, the area | region which a horizontal tab line and a leader line occupy on the surface of a solar cell module can be reduced. As a result, the module conversion efficiency of the solar cell module is improved, and a light transmitting substrate, a sealing material, a back surface protective material, an aluminum frame, and the like necessary for the solar cell module are reduced or reduced in number. It can contribute to the production of a solar cell module that is less expensive and consumes less energy during production, and can further reduce the weight. Further, since the horizontal tab lines and the lead lines can be hidden, the uniformity of the shape of the constituent members existing on the light receiving surface of the solar cell module is increased, and the overall appearance can be improved to a clean impression.

  As described above, the solar cell module according to the present invention is useful in that it can be reduced in size and weight, and can be improved in appearance design, and is particularly limited in the size and weight of the object to be installed. Suitable for installation in places and places where aesthetics are required.

  DESCRIPTION OF SYMBOLS 1 Solar cell, 2 Translucent board | substrate, 3 Sealing material, 3a Light-receiving surface side sealing material, 3b Back surface side sealing material, 4 Back surface protection material, 5 Tab line, 6a-6e Horizontal tab line, 7a, 7b Lead wire, 8 sealing material, 9 aluminum frame, 10 solar cell string, 11 crystalline silicon substrate, 12, 15 intrinsic amorphous silicon thin film, 13 p-type silicon thin film, 14, 17 transparent conductive film, 16 n-type Silicon-based thin film, 18, 19 Fine linear collector electrode, 20a-20c bypass diode, 21 Adhesive, 22 Insulation coating, 24 Terminal box, 30 Upper casing, 31 Lower casing, 32 Heater stage, 33 Diaphragm , 34 O-ring, 40 solar cell panel, 50, 60 solar cell module.

Claims (12)

A solar cell string formed by connecting a plurality of solar cells with tab wires, and
A translucent substrate;
A back surface protective material in which a plurality of the solar cell strings are arranged between the translucent substrate;
A lateral tab line electrically connecting a plurality of the solar cell strings in series;
A lead wire for extracting power from the plurality of solar cell strings electrically connected in series by the horizontal tab wires;
A solar cell module including a solar cell panel having a sealing material for sealing a plurality of the solar cell strings between the translucent substrate and the back surface protective material,
The solar cell module, wherein the horizontal tab line and the lead-out line are arranged on a side surface of the translucent substrate. Comprising an aluminum frame mounted around the solar cell panel;
2. The solar cell module according to claim 1, wherein the horizontal tab line and the lead wire are invisible from the light receiving surface side of the solar cell panel by the aluminum frame.   3. The solar cell module according to claim 1, wherein the horizontal tab line and the lead line are bonded to a side surface of the translucent substrate.   The said sealing material and the said back surface protection material have covered the side surface of the said translucent board | substrate, and have sealed the said horizontal tab line and the said lead wire, The any one of Claim 1 to 3 characterized by the above-mentioned. The solar cell module according to item.   The solar cell module according to claim 4, wherein the sealing material and the back surface protective material have a flat end surface with respect to a surface of the translucent substrate.   The tab line connected to the solar cell arranged at the end of each solar cell string is bent to the light receiving surface side of the translucent substrate and connected to one of the horizontal tab line and the lead line. The solar cell module according to claim 1, wherein the solar cell module is a solar cell module.   The said horizontal tab line and the said lead-out line are arranged in the thickness direction of the said translucent board | substrate, and are arrange | positioned at the side surface of this translucent board | substrate, The any one of Claim 1 to 6 characterized by the above-mentioned. Solar cell module.   The solar cell module according to any one of claims 1 to 6, wherein the horizontal tab line and the lead-out line are disposed so as to overlap with a side surface of the translucent substrate.   The solar cell module according to any one of claims 1 to 8, wherein the horizontal tab line and the lead-out line have an insulating coating. Connecting a plurality of solar cells with tab wires to form a plurality of solar cell strings;
Translucent a horizontal tab line for electrically connecting a plurality of the solar cell strings in series and a lead line for taking out electric power from the plurality of solar cell strings connected in series by the horizontal tab lines Placing on the side of the substrate;
A step of disposing a surface-side sealing material and a plurality of the solar cell strings on the translucent substrate on which the lateral tab lines and the lead wires are disposed on the side surfaces;
Connecting the tab line connected to the solar cell located at the end of each solar cell string to one of the horizontal tab line and the lead line; and
Arranging a back side sealing material and a back side protective material on the plurality of solar cell strings;
The front surface side sealing material and the back surface side sealing material are integrated to form a sealing material, and a plurality of the solar cell strings are interposed between the translucent substrate and the back surface protective material with the sealing material. A laminating process for sealing;
Have
In the laminating step, the lateral tab line and the lead-out line are sealed with the back surface side sealing material and the back surface protection material covering the side surface of the translucent substrate. Production method.   11. The method for manufacturing a solar cell module according to claim 10, wherein the back surface sealing material and the back surface protection material that are larger than the light transmissive substrate by twice the thickness of the light transmissive substrate are used.   Using the back surface sealing material and the back surface protective material that are larger than the translucent substrate, and after the laminating step, the sealing material and the back surface protective material protruding to the front surface side of the translucent substrate, It removes along the surface of a translucent board | substrate, The manufacturing method of the solar cell module of Claim 10 characterized by the above-mentioned.

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