JP5089456B2 - Crimping apparatus and solar cell module manufacturing method - Google Patents

Description

  The present invention relates to a crimping device for crimping a wiring material to a solar cell and a method for manufacturing a solar cell module.

  Solar cells are expected as a new energy source because they can directly convert clean and inexhaustible sunlight into electricity.

  Conventionally, the semiconductor wafer which comprises a solar cell is produced by slicing a columnar semiconductor ingot using a wire saw (for example, patent document 1). A grinding liquid containing abrasive grains is supplied to the wire of the wire saw. The semiconductor ingot is sliced by a wire to which abrasive grains are attached.

  Here, generally, the output per solar cell is about several watts. Therefore, when a solar cell is used as a power source for a house or a building, a solar cell module including a plurality of solar cells is used. The plurality of solar cells are arranged along the arrangement direction and are electrically connected to each other by a wiring material. The wiring material is connected along the arrangement direction on the solar cell.

As a method of connecting the wiring material to the solar cell, a method of crimping the wiring material to the solar cell using a resin adhesive is known (for example, Patent Document 2). Specifically, after the resin adhesive and the wiring material are sequentially arranged on the solar cell mounted on the mounting table, the wiring material is pressed against the solar cell using a crimping device. The crimping device can press the wiring member against the solar cell with a predetermined pressure. The crimping surface facing the wiring member of the crimping device is a uniform plane.
JP 7-205140 A JP 2005-101519 A

  Here, a semiconductor wafer manufactured using a wire saw may have variations in overall or partial thickness. Specifically, the semiconductor wafer varies in thickness according to a change in the amount of abrasive grains attached to the wire. For this reason, in a solar cell manufactured using such a semiconductor wafer, there is a variation in overall thickness or partial thickness corresponding to the variation in thickness of the semiconductor wafer.

  When a wiring material is crimped to the solar cell having such a thickness variation using the above-described crimping apparatus, there are the following problems. That is, since the wiring material is pressed against the solar cell by a uniform plane (crimp surface), stress concentrates on the portion where the thickness of the solar cell is large. Therefore, there is a possibility that the solar cell may be cracked or chipped. For the same reason, the wiring material cannot be sufficiently pressed against the portion where the thickness of the solar cell is small. For this reason, there is a risk of poor adhesion between the solar cell and the wiring material.

  This invention is made | formed in view of the above-mentioned situation, and it aims at providing the manufacturing method of the crimping | compression-bonding apparatus and solar cell module which can crimp | bond a wiring material to a solar cell favorably.

  A crimping apparatus according to one aspect of the present invention is a crimping apparatus that crimps a wiring member disposed along a predetermined direction on a main surface of a solar cell to the main surface, and is along the predetermined direction. A plurality of crimping heads arranged are provided, and each of the plurality of crimping heads is independently movable toward the wiring member.

  According to such a pressure bonding apparatus, since the pressure applied to the solar cell can be dispersed, it is possible to prevent stress from being concentrated on a portion where the thickness of the solar cell is large. Moreover, since a pressure can be applied also to the part with a small thickness of a solar cell, a solar cell and a wiring material can be adhere | attached also in a part with a small thickness of a solar cell. As mentioned above, a wiring material can be favorably crimped | bonded to a solar cell.

  In one aspect of the present invention, each of the plurality of crimping heads includes a heating unit that heats each of the plurality of crimping heads, and each of the plurality of crimping heads is disposed between the main surface and the wiring member by the heating unit. It may be heated above the temperature at which the adhesive is cured.

  In one aspect of the present invention, each of the plurality of crimping heads may be capable of swinging about an axis along a direction substantially orthogonal to the predetermined direction in plan view.

  In one aspect of the present invention, the plurality of pressure-bonding heads are provided between first and second pressure-bonding heads provided at both ends of the plurality of pressure-bonding heads, and the first and second pressure-bonding heads. And the width of at least one of the first or second pressure-bonding heads may be different from the width of the third pressure-bonding head.

  A method for manufacturing a solar cell module according to one aspect of the present invention is a method for manufacturing a solar cell module having a plurality of solar cells electrically connected by a wiring material, on the main surface of the solar cell, Step A for sequentially arranging the resin adhesive and the wiring material along a predetermined direction, and Step B for crimping the wiring material to the main surface by a plurality of pressure bonding heads arranged along the predetermined direction. And the step B is to move each of the plurality of crimping heads independently toward the wiring member.

  In one aspect of the present invention, in the step B, each of the plurality of crimping heads may be heated to a temperature equal to or higher than a temperature at which the resin adhesive is cured.

  In one aspect of the present invention, the plurality of pressure-bonding heads are provided between first and second pressure-bonding heads provided at both ends of the plurality of pressure-bonding heads, and the first and second pressure-bonding heads. And the width of at least one of the first or second pressure-bonding head is different from the width of the third pressure-bonding head in the predetermined direction, A step of pressure-bonding the wiring member to the main surface using a pressure-bonding head other than the second pressure-bonding head, and a pressure-bonding head other than the first pressure-bonding head among the plurality of pressure-bonding heads. And a step of pressure-bonding the wiring material to the main surface.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the crimping | compression-bonding apparatus and solar cell module which can crimp | bond a wiring material to a solar cell favorably can be provided.

  Next, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones. Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, it is a matter of course that portions having different dimensional relationships and ratios are included between the drawings.

[First Embodiment]
<Schematic configuration of solar cell module>
Hereinafter, a schematic configuration of the solar cell module 100 according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 is a side view of the solar cell module 100 according to the first embodiment of the present invention. FIG. 2 is a plan view of the light receiving surface side of the solar cell string 1.

  As shown in FIG. 1, the solar cell module 100 includes a solar cell string 1, a light receiving surface side protective material 2, a back surface side protective material 3, and a sealing material 4. The solar cell module 100 is configured by sealing the solar cell string 1 with a sealing material 4 between the light receiving surface side protective material 2 and the back surface side protective material 3.

  As shown in FIGS. 1 and 2, the solar cell string 1 includes a plurality of solar cells 10, a wiring material 5, and a resin adhesive 6. The solar cell string 1 is configured by electrically connecting a plurality of solar cells 10 arranged along the first direction to each other by the wiring member 5.

  Solar cell 10 has a light receiving surface (upper surface in the drawing) on which sunlight enters and a back surface (lower surface in the drawing) provided on the opposite side of the light receiving surface. The light receiving surface and the back surface are the main surfaces of the solar cell 10. Moreover, the solar cell 10 is provided with the electrode 13 for a connection, as shown in FIG.1 and FIG.2. The configuration of the solar cell 10 will be described later.

  The wiring member 5 electrically connects the plurality of solar cells 10 to each other. As shown in FIGS. 1 and 2, the wiring member 5 includes a connection electrode 13 formed on the light receiving surface side of one solar cell 10, and a back surface side of another solar cell 10 adjacent to the one solar cell 10. It is bonded to the connection electrode 13 formed through the resin adhesive 6. As shown in FIG. 2, the wiring member 5 is arranged along a first direction in which a plurality of solar cells 10 are arranged.

  As the wiring member 5, a conductive material such as copper formed into a thin plate shape or a twisted wire shape can be used, but is not limited thereto. As the wiring member 5, silver, aluminum, nickel, tin, gold, or an alloy thereof may be used. The wiring member 5 may have a structure in which a core material such as copper, silver, aluminum, nickel, or gold is plated with tin, solder, or the like. The width of the wiring member 5 is formed substantially equal to the width of the connection electrode 13 in FIG. 2, but may be different from the width of the connection electrode 13.

  As shown in FIGS. 1 and 2, the resin adhesive 6 is disposed between the connection electrode 13 of the solar cell 10 and the wiring member 5. As the resin adhesive 6, for example, an acrylic resin, a highly flexible polyurethane-based, or epoxy-based thermosetting resin adhesive can be used. The resin adhesive 6 may include a plurality of conductive particles. As the conductive particles, nickel, silver, nickel with gold coating, copper with tin plating, or the like can be used. The resin adhesive 6 is preferably cured at a temperature below the melting point of the solder, that is, about 200 ° C. or less.

  The light receiving surface side protective material 2 is disposed on the light receiving surface side of the sealing material 4 and protects the surface of the solar cell module 100. As the light-receiving surface side protective material 2, glass having translucency and water shielding properties, translucent plastic, or the like can be used.

  The back surface side protective material 3 is disposed on the back surface side of the sealing material 4 and protects the back surface of the solar cell module 100. As the back surface side protective material 3, a resin film such as PET (Polyethylene Terephthalate), a laminated film having a structure in which an Al foil is sandwiched between resin films, and the like can be used.

  The sealing material 4 seals the solar cell string 1 between the light receiving surface side protective material 2 and the back surface side protective material 3. As the sealing material 4, a translucent resin such as EVA, EEA, PVB, silicone, urethane, acrylic, or epoxy can be used.

  An Al frame (not shown) can be attached to the outer periphery of the solar cell module 100 having the above configuration.

<Configuration of solar cell>
Next, the configuration of the solar cell 10 according to the first embodiment of the present invention will be described with reference to FIG. FIG. 3 is a plan view of the solar cell 10 on the light receiving surface side.

  As shown in FIG. 3, the solar cell 10 includes a photoelectric conversion unit 11, a thin wire electrode 12, and a connection electrode 13.

  The photoelectric conversion unit 11 has a light receiving surface (upper surface in FIG. 1) on which sunlight is incident and a back surface (lower surface in FIG. 1) provided on the opposite side of the light receiving surface. The light receiving surface and the back surface are the main surfaces of the photoelectric conversion unit 11. The photoelectric conversion unit 11 generates a photogenerated carrier by receiving light on the light receiving surface of the photoelectric conversion unit 11. The photogenerated carrier refers to a pair of holes and electrons generated when sunlight is absorbed by the photoelectric conversion unit 11.

  The photoelectric conversion unit 11 has a p-type region and an n-type region inside (not shown). A semiconductor junction is formed at the interface between the p-type region and the n-type region in the photoelectric conversion unit 11. The photoelectric conversion unit 11 can be formed using a semiconductor wafer made of a crystalline semiconductor material such as single crystal Si or polycrystalline Si, or a semiconductor material such as a compound semiconductor material such as GaAs or InP. The photoelectric conversion unit 11 has a structure in which the characteristics of the heterojunction interface are improved by sandwiching a substantially intrinsic amorphous silicon layer between the single crystal silicon wafer and the amorphous silicon layer, that is, a so-called HIT. You may have a structure. Since the semiconductor wafer used in the photoelectric conversion unit 11 according to the first embodiment of the present invention is manufactured by slicing a columnar semiconductor ingot using a wire saw, there is a variation in overall or partial thickness. Have. Therefore, the photoelectric conversion unit 11 and the solar cell 10 using the photoelectric conversion unit 11 have an overall or partial thickness variation corresponding to the thickness variation of the semiconductor wafer.

  The thin wire electrode 12 is a collection electrode that collects photogenerated carriers from the photoelectric conversion unit 11. As shown in FIG. 3, the thin wire electrode 12 is formed on the light receiving surface of the photoelectric conversion unit 11 along a second direction substantially orthogonal to the first direction in which the plurality of solar cells 10 are arranged. The plurality of fine wire electrodes 12 are arranged in parallel along the first direction. The fine wire electrode 12 is, for example, a resin-type conductive paste using a resin material as a binder and conductive particles as a filler, or a sintered conductive paste (so-called conductive particles, glass frit, organic vehicle, organic solvent, etc.) It can be formed by a printing method using a ceramic paste. As the conductive particles, gold, silver, nickel, aluminum, tin, or an alloy thereof can be used. The dimensions and number of the thin wire electrodes 12 can be appropriately set in consideration of the size and physical properties of the photoelectric conversion unit 11.

  The connection electrode 13 is an electrode connected to the wiring member 5. As shown in FIG. 3, the connection electrode 13 is formed along the first direction on the light receiving surface of the photoelectric conversion unit 11. Therefore, the connection electrode 13 intersects with the plurality of fine wire electrodes 12 and is electrically connected to the plurality of fine wire electrodes 12. On the connection electrode 13, the wiring member 5 is disposed via the resin adhesive 6. The connection electrode 13 can be formed by a printing method using a resin-type conductive paste or a sintered-type conductive paste, similarly to the thin wire electrode 12. The dimensions and number of the connection electrodes 13 can be appropriately set in consideration of the size and physical properties of the photoelectric conversion unit 11.

  In addition, on the back surface of the photoelectric conversion unit 11, the thin line electrode 12 and the connection electrode 13 having the same shape as the thin line electrode 12 and the connection electrode 13 formed on the light receiving surface of the photoelectric conversion unit 11 are formed. However, it is not limited to this. For example, a part of the conductive film formed on substantially the entire back surface of the photoelectric conversion unit 11 may be used as a connection electrode, or a separate connection electrode may be provided on the conductive film.

<Method for manufacturing solar cell module>
Next, a method for manufacturing the solar cell module 100 according to the first embodiment of the present invention will be described with reference to FIG.

  First, the solar cell 10 is produced. Specifically, first, a 100 mm square n-type single crystal silicon substrate is etched to form fine irregularities on the light receiving surface of the n-type single crystal silicon substrate. Next, an i-type amorphous silicon layer and a p-type amorphous silicon layer are sequentially stacked on the light-receiving surface side of the n-type single crystal silicon substrate using a CVD (chemical vapor deposition) method. Similarly, an i-type amorphous silicon layer and an n-type amorphous silicon layer are sequentially stacked on the back side of the n-type single crystal silicon substrate.

  Next, a transparent conductive film such as an ITO film is formed on the light receiving surface side of the p-type amorphous silicon layer by using a PVD (physical vapor deposition) method. Similarly, a transparent conductive film such as an ITO film is formed on the back side of the n-type amorphous silicon layer. The photoelectric conversion part 11 is produced by the above.

  Next, using a printing method such as a screen printing method, an epoxy thermosetting silver paste is arranged in a predetermined pattern on the light receiving surface and the back surface of the photoelectric conversion unit 11. As shown in FIG. 3, the predetermined pattern refers to a lattice shape formed by the fine line electrodes 12 extending along the second direction and the connection electrodes 13 intersecting the fine line electrodes 12. Next, the silver paste is heated and cured under predetermined conditions. Thereby, the thin wire electrode 12 and the connection electrode 13 are formed on the photoelectric conversion unit 11. Thus, the solar cell 10 is produced.

  Next, one solar cell 10 is placed on the mounting table 20. Next, the resin adhesive 6 is disposed on the connection electrode 13 formed on the light receiving surface side of one solar cell 10. Next, the wiring member 5 is disposed on the resin adhesive 6 along the first direction.

  Next, the wiring member 5 is crimped to the connection electrode 13 using the crimping device 30. Specifically, the crimping device 30 will be described with reference to FIG. As shown in FIG. 4, the crimping device 30 includes a plurality of crimping heads 31 and a heating unit 32 provided inside each of the plurality of crimping heads 31. The multiple crimping heads 31 are arranged along the first direction. As shown in FIG. 4, each of the plurality of crimping heads 31 is independently movable toward the wiring material 5 disposed on the connection electrode 13 of the solar cell 10. For example, each of the plurality of crimping heads 31 can pressurize the wiring member 5 independently. In addition, for example, a pressure mechanism that pressurizes each of the plurality of pressure-bonding heads 31 is provided in the pressure-bonding device 30, and a spring mechanism is provided in each of the plurality of pressure-bonding heads 31. May be changed according to the thickness of the solar cell 10. The heating unit 32 is made of, for example, a molybdenum wire and heats the crimping head 31 by energization. The heating unit 32 heats the pressure-bonding head 31 to a temperature higher than the temperature at which the resin adhesive 6 disposed between the connection electrode 13 and the wiring member 5 is cured. That is, the wiring member 5 is heated by pressurizing the wiring member 5 with the pressure-bonding head 31 heated by the heating unit 32. The resin adhesive 6 is cured by heat transmitted through the wiring member 5. By applying pressure and heating to the wiring member 5 using such a crimping device 30, the wiring member 5 is crimped to the connection electrode 13. In the crimping step described above, in the first direction, the length of the wiring member 5 to be pressurized and heated is made shorter than the length of the resin adhesive 6, and a part of the resin adhesive 6 is removed. Let it be an uncured area.

  Similarly, the wiring member 5 is pressure-bonded to the connection electrode 13 formed on the back surface side of the other solar cell 10 adjacent to the one solar cell 10. The solar cell string 1 is produced by repeating the above steps.

  Next, an EVA (sealing material 4) sheet, a solar cell string 1, an EVA (sealing material 4) sheet, and a PET sheet (back surface side protection material 3) are sequentially placed on the glass substrate (light-receiving surface side protection material 2). Laminate to make a laminate. Next, the EVA is cured by heat-pressing the laminate in a vacuum atmosphere. Thus, the solar cell string 1 is sealed by the sealing material 4 between the light receiving surface side protective material 2 and the back surface side protective material 3.

  The solar cell module 100 is manufactured through the above steps. Note that a terminal box, an Al frame or the like can be attached to the solar cell module 100.

<Action and effect>
The solar cell module 100 according to the first embodiment of the present invention is manufactured by crimping the wiring member 5 to the connection electrode 13 by a crimping device 30 including a plurality of crimping heads 31. Each of the plurality of crimping heads 31 provided in the crimping apparatus 30 is movable independently of the wiring member 5.

  By using such a crimping device 30, the pressure applied to the solar cell 10 can be dispersed, so that stress can be prevented from concentrating on a portion where the thickness of the solar cell 10 is large. Therefore, it is possible to prevent the solar cell 10 from being cracked or chipped. In addition, since pressure can be applied to the portion where the thickness of the solar cell 10 is small, the connection electrode 13 and the wiring member 5 can be bonded even in the portion where the thickness of the solar cell 10 is small. From the above, even if the solar cell 10 has a variation in overall thickness or partial thickness in accordance with the variation in thickness of the semiconductor wafer, the wiring material 5 is favorably applied to the connection electrode 13 of the solar cell 10. Can be crimped.

  Further, in the first direction, the length of the wiring member 5 to be pressurized and heated is made shorter than the length of the resin adhesive 6, and a part of the resin adhesive 6 is made an uncured region. The stress generated inside the resin adhesive 6 can be reduced. According to this, the curvature of the solar cell 10 can be suppressed.

<Modification of First Embodiment>
Below, the manufacturing method of the solar cell module 100 which concerns on the modification of 1st Embodiment of this invention is demonstrated. In this modification, as shown in FIG. 5A, a crimping device 30 including a plurality of crimping heads 31 that can swing around an axis 33 along a second direction substantially orthogonal to the first direction is used. .

  FIG. 5B is a diagram illustrating a state in which the wiring member 5 is crimped to the connection electrode 13 using the crimping device 30 according to the modification of the first embodiment. As shown in FIG. 5B, stress is concentrated on a portion where the thickness of the solar cell 10 is large by crimping the wiring member 5 with a plurality of crimping heads 31 that can swing around the axis 33. Further suppression can be achieved. Therefore, it is possible to further suppress the occurrence of cracks and chips in the solar cell 10. Further, since the pressure applied to the portion where the thickness of the solar cell 10 is small can be increased, the connection electrode 13 and the wiring member 5 can be pressure-bonded more accurately even in the portion where the thickness of the solar cell 10 is small. it can.

[Second Embodiment]
In the following, a second embodiment of the present invention will be described. In the following, differences between the first embodiment and the second embodiment described above will be mainly described. About the structure of the solar cell module 100, the solar cell string 1, and the solar cell 10, since it is the same as that of 1st Embodiment mentioned above, description is abbreviate | omitted here.

<Method for manufacturing solar cell module>
A method for manufacturing the solar cell module 100 according to the second embodiment of the present invention will be described with reference to FIG.

  First, the solar cell 10 is produced similarly to 1st Embodiment mentioned above. Next, one solar cell 10 is disposed on the mounting table 20, and the resin adhesive 6 and the wiring member 5 are sequentially disposed on the connection electrode 13 formed on the light receiving surface side of the one solar cell 10. .

  Next, the wiring member 5 is crimped to the connection electrode 13 using the crimping device 40. Specifically, the crimping device 40 will be described with reference to FIG. As shown in FIG. 6A, the crimping device 40 includes a plurality of crimping heads 41 and a heating unit 42 provided inside each of the plurality of crimping heads 41. The plurality of crimping heads 41 are provided between the first and second crimping heads 41 a and 41 d and the first and second crimping heads 41 a and 41 d provided at both ends of the plurality of crimping heads 41. 3 crimping heads 41b and 41c. The multiple crimping heads 41 are arranged along the first direction. The width of at least one of the first or second pressure bonding heads 41a and 41d is different from the width of the third pressure bonding heads 41b and 41c in the first direction. FIG. 6 shows a case where the widths of the first and second crimping heads 41a and 41d are substantially the same.

  As shown in FIG. 6, each of the plurality of crimping heads 41 is independently movable toward the wiring member 5 arranged on the connection electrode 13 of the solar cell 10. For example, each of the plurality of crimping heads 41 can pressurize the wiring member 5 independently. In addition, for example, a pressure mechanism that pressurizes each of the plurality of pressure-bonding heads 41 is provided in the pressure-bonding device 40, and a spring mechanism is provided in each of the plurality of pressure-bonding heads 41. May be changed according to the thickness of the solar cell 10. The heating unit 42 is made of, for example, a molybdenum wire and heats the crimping head 41 by energization. The heating unit 42 heats the pressure-bonding head 41 to a temperature higher than the temperature at which the resin adhesive 6 disposed between the connection electrode 13 and the wiring member 5 is cured.

  In the manufacturing method of the solar cell module 100 according to the second embodiment of the present invention, the step of pressure-bonding the wiring member 5 to the connection electrode 13 is configured by two steps. In the first step, as shown in FIG. 6B, a crimping head other than one second crimping head 41d among the plurality of crimping heads 41, that is, the first crimping head 41a and the third crimping head. The wiring member 5 is crimped to the connection electrode 13 using 41b and 41c. Specifically, the wiring member 5 is heated by pressurizing the wiring member 5 with the first pressure-bonding head 41 a and the third pressure-bonding heads 41 b and 41 c heated by the heating unit 42. In the second step, as shown in FIG. 6C, a plurality of pressure bonding heads 41 other than the first pressure bonding head 41a, that is, the second pressure bonding head 41b and the third pressure bonding head 41c, The wiring member 5 is pressure-bonded to the connection electrode 13 using 41d. Specifically, the wiring member 5 is heated by pressurizing the wiring member 5 with the second pressure bonding head 41b and the third pressure bonding heads 41c and 41d heated by the heating unit 42. The resin adhesive 6 is cured by heat transmitted through the wiring member 5. As described above, the wiring member 5 is pressure-bonded to the connection electrode 13.

  Similarly, the wiring member 5 is bonded to the connection electrode 13 formed on the back surface side of the other solar cell 10 adjacent to the one solar cell 10. The solar cell string 1 is produced by repeating the above steps.

  Next, similarly to the first embodiment described above, the solar cell string 1 is sealed with the sealing material 4 between the light receiving surface side protective material 2 and the back surface side protective material 3. The solar cell module 100 is manufactured through the above steps. Note that a terminal box, an Al frame or the like can be attached to the solar cell module 100.

<Action and effect>
The solar cell module 100 according to the second embodiment of the present invention includes a first pressure-bonding head 41a, 41d and a third pressure-bonding head 41b provided between the first and second pressure-bonding heads 41a, 41d. , 41c, and the crimping apparatus 40 including a plurality of crimping heads 41 is produced by crimping the wiring member 5 to the connection electrode 13. Each of the plurality of pressure-bonding heads 41 provided in the pressure-bonding device 40 is independently movable with respect to the wiring member 5, and the width of at least one of the first or second pressure-bonding heads 41a and 41d is the first direction. However, the width of the third pressure-bonding heads 41b and 41c is different. The step of crimping the wiring member 5 to the connection electrode 13 using such a crimping device 40 is performed by using the first crimping head 41 a and the third crimping heads 41 b and 41 c to connect the wiring member 5 to the connection electrode 13. It comprises a first step of crimping and a second step of crimping the wiring member 5 to the connection electrode 13 using the second crimping head 41b and the third crimping heads 41c and 41d.

  In the first step, since there are gaps between the first pressure-bonding head 41a and the third pressure-bonding head 41b and between the third pressure-bonding head 41b and the third pressure-bonding head 41c, resin bonding It is difficult for pressure and heat to be applied to portions of the agent 6 corresponding to these gaps. Therefore, an uncured region may remain in the resin adhesive 6. Therefore, in the second step, a third pressure bonding head is used by using a combination of pressure bonding heads different from the combination used in the first step (that is, the second pressure bonding head 41b and the third pressure bonding head 41c, 41d). At least a part of the gap between the head 41b and the third crimping head 41c and the gap between the third crimping head 41c and the second crimping head 41d deviates from the uncured region of the resin adhesive 6 in the first direction. . Therefore, at least a part of the uncured region of the resin adhesive 6 is cured by the second step. Therefore, according to the method for manufacturing the solar cell module 100 according to the second embodiment of the present invention, since the uncured region of the resin adhesive 6 can be reduced, the adhesive strength between the connection electrode 13 and the wiring member 5 is increased. It can be further increased.

[Other Embodiments]
Although the present invention has been described according to the above-described embodiments, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art.

  For example, in the first embodiment and the second embodiment described above, in the first direction, the length of the area to be pressed and heated in the wiring member 5 is made shorter than the length of the resin adhesive 6, and the resin bonding is performed. Although the case where the edge part of the agent 6 is an uncured region has been described, the present invention is not limited to this, and the length of the region of the wiring member 5 to be pressurized and heated is substantially equal to the length of the resin adhesive 6. It is good.

  Further, in the first embodiment and the second embodiment described above, the case where the connection electrode 13 is formed on the light receiving surface and the back surface of the photoelectric conversion unit 11 and the wiring member 5 is crimped to the connection electrode 13 has been described. However, it is not limited to this. For example, the wiring material 5 may be directly pressure-bonded on the light receiving surface or the back surface of the solar cell 10 without forming the connection electrodes 13 on the light receiving surface side and the back surface side of the solar cell 10.

  In the first embodiment described above, the case where the wiring member 5 is pressurized and heated using the three crimping heads 31 has been described, but the number of crimping heads is not limited to three.

  In the second embodiment described above, the case where the widths in the first direction of the third pressure-bonding heads 41b and 41c are substantially the same has been described. However, the present invention is not limited to this. The width of 41c may be different. Further, the number of the third crimping heads provided between the first and second crimping heads 41a and 41d is not limited to two, but between the first and second crimping heads 41a and 41b. Three or more third crimping heads may be provided. At this time, for example, as shown in FIG. 7, a width β (β1 in FIG. 7) from the end of one crimping head to the end of another crimping head among the plurality of third crimping heads 41b, 41c, 41e. , Β2, β3...) Are different from at least one of the width α1 of the first pressure bonding head or the width α2 of the second pressure bonding head, so that the uncured region of the resin adhesive can be eliminated. Although FIG. 7 shows the case where the widths α1, α2 of the first and second pressure-bonding heads are substantially the same, the widths α1, α2 of the first and second pressure-bonding heads may be different.

  In the first embodiment and the second embodiment described above, the case where the heating unit is provided inside each of the plurality of pressure bonding heads has been described. However, the present invention is not limited to this, and each of the plurality of pressure bonding heads is heated. The pressure bonding device may include one heating unit.

  As described above, the present invention naturally includes various embodiments not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

  Hereinafter, the solar cell according to the present invention will be specifically described with reference to examples. However, the present invention is not limited to those shown in the following examples, and can be implemented with appropriate modifications within a range not changing the gist thereof.

[Output reduction rate evaluation]
Solar cell modules according to Example 1, Example 2, Example 3, and Comparative Example were produced as follows, and the output reduction rates were compared.

<Example 1>
A solar cell according to Example 1 was produced as follows. First, an n-type single crystal silicon substrate having a thickness of 200 μm was anisotropically etched with an alkaline aqueous solution to form fine irregularities on the light receiving surface side of the n-type single crystal silicon substrate. Next, an i-type amorphous silicon layer and a p-type amorphous silicon layer were sequentially stacked on the light-receiving surface side of the n-type single crystal silicon substrate using a plasma CVD method or the like. Next, an i-type amorphous silicon layer and an n-type amorphous silicon layer were sequentially stacked on the back side of the n-type single crystal silicon substrate. Next, an ITO layer was formed on the p-type amorphous silicon layer and the n-type amorphous silicon layer by sputtering. The photoelectric conversion part (photoelectric conversion part 11) was produced by the above.

  Next, a paste composed of a conductive filler mainly composed of silver and an epoxy thermosetting resin is screen-printed on the light receiving surface and the back surface of the photoelectric conversion unit (photoelectric conversion unit 11). And an annealing process at 200 ° C. was performed. Thereby, a fine wire electrode (fine wire electrode 12) and a connection electrode (connection electrode 13) were formed. Thus, a 100 mm square solar cell was produced.

  Next, one solar cell was placed on the mounting table. Next, an epoxy resin adhesive (resin adhesive 6) containing 5 vol% of nickel particles was placed on the connection electrode (connection electrode 13) formed on the light receiving surface side of one solar cell. Next, the wiring material (wiring material 5) was arrange | positioned along the 1st direction on the resin adhesive (resin adhesive 6). As the wiring material (wiring material 5), a tin-plated copper thin film having a width of 1.5 mm was used.

  Next, the wiring material (wiring material 5) was crimped to the connection electrode (connection electrode 13) using the crimping device (crimping device 30) shown in FIG. Specifically, the wiring material (wiring material 5) was pressure-bonded to the connection electrode (connection electrode 13) by three pressure bonding heads (pressure bonding head 31) provided in the pressure bonding device (pressure bonding device 30). The length of each crimping head (crimping head 31) was 31.3 mm, and the gap between each crimping head (crimping head 31) was 3 mm. The temperature of the crimping head (crimping head 31) was 200 ° C., and the pressure applied from the crimping head (crimping head 31) to the wiring member (wiring member 5) was 2 MPa. The pressure bonding time was 5 minutes.

  Under the same conditions, a plurality of solar cells were connected by a wiring material (wiring material 5) to produce a solar cell string (solar cell string 1). Next, an EVA (sealing material 4) sheet, a solar cell string (solar cell string 1), an EVA (sealing material 4) sheet, and a PET sheet (back side protection) on a glass substrate (light-receiving surface side protective material 2). The material 3) was sequentially laminated to obtain a laminate. Next, EVA was hardened by carrying out the thermocompression bonding of the said laminated body in a vacuum atmosphere. The solar cell module which concerns on Example 1 was produced by the above.

<Example 2>
In Example 2, the crimping device used when crimping the wiring material (wiring material 5) to the connecting electrode (connecting electrode 13) was changed to the crimping device (crimping device 30) shown in FIG. Except this point, the second embodiment is the same as the first embodiment. The crimping device (crimping device 30) shown in FIG. 5 has a plurality of crimping heads (crimping heads 31) that can swing around an axis (axial center 33) along a second direction substantially orthogonal to the first direction. ).

<Example 3>
A solar cell according to Example 3 was produced as follows. First, a solar cell was produced in the same manner as in Example 1 described above. Next, in the same manner as in the first embodiment described above, one solar cell is arranged on the mounting table, and on the connection electrode (connection electrode 13) formed on the light receiving surface side of the one solar cell. The resin adhesive (resin adhesive 6) and the wiring material (wiring material 5) were sequentially arranged.

  Next, the wiring material (wiring material 5) was pressure-bonded to the connection electrode (connection electrode 13) using the pressure bonding device (crimping device 40) shown in FIG. Specifically, first, of the four crimping heads provided in the crimping device (crimping device 40) as the first step, the first crimping head (first crimping head 41a) and the two third crimping heads. The wiring material (wiring material 5) was pressure-bonded to the connection electrode (connection electrode 13) using the (third pressure bonding heads 41b and 41c). Next, as a second step, of the four crimping heads provided in the crimping device (crimping device 40), the second crimping head (second crimping head 41d) and the two third crimping heads (third The crimping heads 41c and 41d) were used to crimp the wiring member (wiring member 5) to the connecting electrode (connecting electrode 13). The width of each of the first pressure-bonding head (pressure-bonding head 41a) and the second pressure-bonding head (pressure-bonding head 41d) was 24 mm, and the width of each of the third pressure-bonding heads (pressure-bonding heads 41b and 41c) was 35 mm. The gaps between the pressure bonding heads (pressure bonding heads 41) were 3 mm, respectively. The temperature of the pressure bonding head (pressure bonding head 41) was 200 ° C., and the pressure applied from the pressure bonding head (pressure bonding head 41) to the wiring material (wiring material 5) was 2 MPa. The crimping time was 5 minutes in each of the first step and the second step.

  Under the same conditions, a plurality of solar cells were connected by a wiring material (wiring material 5) to produce a solar cell string (solar cell string 1). Next, an EVA (sealing material 4) sheet, a solar cell string (solar cell string 1), an EVA (sealing material 4) sheet, and a PET sheet (back side protection) on a glass substrate (light-receiving surface side protective material 2). The material 3) was sequentially laminated to obtain a laminate. Next, EVA was hardened by carrying out the thermocompression bonding of the said laminated body in a vacuum atmosphere. Thus, the solar cell module according to Example 3 was produced.

<Comparative example>
In this comparative example, the crimping device used when crimping the wiring material (wiring material 5) to the connecting electrode (connecting electrode 13) was changed to the crimping device (crimping device 50) shown in FIG. Except this point, the second embodiment is the same as the first embodiment.

  The crimping device (crimping device 50) used in this comparative example includes one crimping head (crimping head 51) as shown in FIG. The length of the pressure bonding head (pressure bonding head 51) was 100 mm. The pressure head 51 was heated to 200 ° C. by heating the pressure head 51 with the heating unit 52. The pressure applied from the pressure bonding head 51 to the wiring member (wiring member 5) was 2 MPa. The pressure bonding time was 5 minutes.

<Output reduction rate evaluation results>
A temperature cycle test was performed on the solar cell modules according to Example 1, Example 2, Example 3 and Comparative Example described above, and the output reduction rate was compared by measuring the output value of the solar cell module before and after the test.

The temperature cycle test was performed for 400 cycles in accordance with JIS C 8917. Moreover, the output value of the solar cell module was measured under light irradiation of AM 1.5 and 100 mW / cm ² . Moreover, the output reduction rate of the solar cell module was calculated by the following formula (1).
(1-output after test / output before test) (1)

Table 1 shows the evaluation results of the output reduction rate. In Table 1, the output decrease rate in Examples 1 to 3 is normalized and expressed as the output decrease rate in the comparative example being 1.00.

  As shown in Table 1, in the solar cell modules according to Examples 1 to 3, it was confirmed that the output decrease rate was lower than that of the solar cell module according to the comparative example. In the first to third embodiments, stress is applied to a portion where the thickness of the solar cell is large by crimping the wiring member to the connection electrode using a plurality of crimping heads arranged along the first direction. This is because concentration can be suppressed and the connection electrode and the wiring member can be bonded with high precision even in a portion where the thickness of the solar cell is small.

  Further, as shown in Table 1, it was confirmed that the output reduction rate in Example 2 was lower than the output reduction rate in Example 1. This is because, in Example 2, by using a plurality of crimping heads that can swing around the axis along the second direction, the solar cell is thicker than in Example 1. This is because the concentration of stress can be further suppressed. Moreover, in Example 2, compared with Example 1, the pressure applied to the part where the thickness of the solar cell is small can be further increased, and the connection electrode and the electrode can be more accurately also in the part where the thickness of the solar cell is small. This is because the wiring material can be crimped.

  Further, as shown in Table 1, it was confirmed that the output reduction rate in Example 3 was lower than the output reduction rate in Example 1. In Example 3, the step of crimping the wiring member 5 to the connection electrode 13 includes the first step of crimping with the first crimping head and the third crimping head, the second crimping head, and the third. And the second step of crimping by the crimping head, and the width of the first and second crimping heads is different from the width of the third crimping head, thereby reducing the uncured region of the resin adhesive. This is because the adhesive strength between the connection electrode and the wiring material could be further increased as compared with Example 1.

It is a side view of the solar cell module 100 which concerns on 1st Embodiment of this invention. It is a top view by the side of the light-receiving surface of the solar cell string 1 which concerns on 1st Embodiment of this invention. It is a top view by the side of the light-receiving surface of the solar cell 10 which concerns on 1st Embodiment of this invention. It is a figure which shows a mode that the wiring material 5 is crimped | bonded to the main surface of the solar cell 10 using the crimping | compression-bonding apparatus 30 which concerns on 1st Embodiment of this invention. It is a figure which shows a mode that the wiring material 5 is crimped | bonded to the main surface of the solar cell 10 using the crimping | compression-bonding apparatus 30 which concerns on the modification of 1st Embodiment of this invention. It is a figure which shows a mode that the wiring material 5 is crimped | bonded to the main surface of the solar cell 10 using the crimping | compression-bonding apparatus 40 which concerns on 2nd Embodiment of this invention. It is a figure which shows the structure of the crimping | compression-bonding apparatus 40 which concerns on other embodiment. It is a figure which shows a mode that the wiring material 5 is crimped | bonded to the main surface of the solar cell 10 using the crimping | compression-bonding apparatus 50 which concerns on a comparative example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Solar cell module, 1 ... Solar cell string, 2 ... Light-receiving surface side protective material, 3 ... Back surface side protective material, 4 ... Sealing material, 5 ... Wiring material, 6 ... Resin adhesive, 10 ... Solar cell, 11 DESCRIPTION OF SYMBOLS ... Photoelectric conversion part, 12 ... Fine wire electrode, 13 ... Connection electrode, 20 ... Mounting stand, 30 ... Crimping device, 31 ... Crimping head, 32 ... Heating part 33 ... Axis, 40 ... Crimping device, 41 ... Crimping head, 41a ... first crimping head, 41d ... second crimping head, 41b, 41c, 41e ... third crimping head, 42 ... heating unit, 50 ... crimping device, 51 ... crimping head, 52 ... heating unit

Claims (2)

  A method for manufacturing a solar cell module having a plurality of solar cells electrically connected by a wiring material,
  On the main surface of the solar cell, a step A for sequentially arranging a resin adhesive and the wiring member along a predetermined direction;
  A step B of crimping the wiring member to the main surface by a plurality of crimping heads arranged with gaps along the predetermined direction;
With
  In step B,
  Moving each of the plurality of crimping heads independently toward the wiring member;
  Each of the plurality of pressure bonding heads is heated by a heating unit provided inside each of the plurality of pressure bonding heads,
  The plurality of crimping heads are:
  First and second crimping heads provided at both ends of the plurality of crimping heads;
  A third crimping head provided between the first and second crimping heads,
  In the predetermined direction, the width of at least one of the first or second crimping head is different from the width of the third crimping head;
  The first, third and second crimping heads are arranged in the predetermined direction in this order,
  Step B is
  A step of pressure-bonding the wiring member to the main surface using a pressure-bonding head other than the second pressure-bonding head among the plurality of pressure-bonding heads;
  The relative positions of the plurality of crimping heads and the plurality of crimping heads are changed, and the wiring member is crimped to the main surface using a crimping head other than the first crimping head among the plurality of crimping heads. Including the step of
The manufacturing method of the solar cell module characterized by the above-mentioned.   In step B,
  Each of the plurality of pressure bonding heads is heated to a temperature higher than the temperature at which the resin adhesive is cured.
The manufacturing method of the solar cell module of Claim 1 characterized by the above-mentioned.

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