JP2008277652A - Manufacturing method for solar battery module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress a warp of a solar battery cell without using a new member when manufacturing a solar battery module using solar battery cells having double-electrode extraction structures on their back faces. <P>SOLUTION: In this manufacturing method for the solar battery module, a first resin layer 12 is formed on a light-receiving member 11. Solar battery cells 13 are placed on the first resin layer 12 with light-receiving faces of the battery cells 13 set to face the surface of the first resin layer 12. In a state that the solar battery cells 13 are placed on the first resin layer 12 with the light-receiving faces set to face the surface of the first resin layer 12, the first resin layer 12 is heated to its melting temperature to bond the battery cells 13 by pressure to the first resin layer 12. Following the pressure bonding, the adjacent solar battery cells 13 are connected electrically to each other via wiring materials 14. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a solar cell module using solar cells that are wired on the back side.

  Solar cells are expected as a new energy source because they can directly convert light from the sun, a clean and inexhaustible energy source, into electricity. In such a solar cell, it is a challenge to reduce the thickness of the solar cell from both the necessity of cost reduction due to the expansion of the solar cell market and the reduction of the amount of silicon raw materials.

In addition, solar cells are required to be thin and highly efficient. One method for improving efficiency is to increase the effective light receiving area. Specifically, a solar battery cell in which a p-doped region and an n-doped region are alternately provided on the back surface provided on the opposite side of the light receiving surface of the solar battery cell and the charge extraction structure is entirely formed on the back surface side. Has been proposed (see Patent Document 1). The solar cell in which the p-side electrode and the n-side electrode are laid only on the back surface side can increase the effective light receiving area. Thereby, conversion efficiency can be improved. Such a solar cell is called a back contact solar cell.
JP 2005-191479 A

  In a solar cell module using a conventional back contact solar cell, a wiring member is connected to a p-side electrode and an n-side electrode formed on the back surface of the solar cell in order to electrically connect adjacent solar cells. However, usually, the thermal expansion coefficient of a wiring material made of metal is extremely larger than that of a semiconductor substrate (for example, a silicon substrate) constituting a solar cell. For this reason, stress is applied to the solar cell due to a temperature change caused by soldering or the like when connecting the wiring material to the solar cell. And this influence becomes remarkably large in the back contact type solar cell in which the connection of the wiring material to both the p-side electrode and the n-side electrode is performed on the back surface, and causes the warpage of the solar cell. And when the curvature of a photovoltaic cell becomes large in this way, in the subsequent process, for example, the modularization process at the time of modularization, it may occur if the photovoltaic cell is broken, and the yield in modularization may be reduced. There is.

  Therefore, the present invention has been proposed in view of the above-described conventional situation, and solar cells are formed by using solar cells that connect both the p-side electrode and the n-side electrode wiring material on the back side. When manufacturing a battery module, it aims at providing the manufacturing method of the solar cell module which can suppress the curvature of a photovoltaic cell and can reduce the yield fall in a sealing process.

  In order to achieve the above-described object, one feature of the present invention is that a plurality of solar cells each having a light-receiving surface that receives light and a back surface provided on the opposite side of the light-receiving surface are arranged only on the back surface side. A method for manufacturing a solar cell module by connecting with a wiring material, the step (A) of disposing a first thermoplastic resin layer on a first protective member, and the first thermoplastic resin layer A step (B) of disposing the solar battery cell on the first thermoplastic resin layer with the surface facing the light receiving surface of the solar battery cell, and the first thermoplastic resin layer being the first Heating to the melting temperature of the thermoplastic resin layer and press-bonding the solar battery cell disposed in the first thermoplastic resin layer to the first thermoplastic resin layer; and the first heat The photovoltaic cells arranged in the plastic resin layer are mutually connected by the wiring material. Step (D) of electrically connecting, step (E) of disposing the second thermoplastic resin layer on the plurality of solar cells, and second protection on the second thermoplastic resin layer And a step (F) of disposing a member.

  According to such a feature, before the solar cells are electrically connected to each other by the wiring material, they are pressure-bonded and fixed to the first thermoplastic resin layer. Therefore, according to this characteristic, the curvature of a photovoltaic cell can be suppressed, without using a reinforcing material. In addition, it is possible to improve yield reduction caused by cell warpage. Thereby, productivity can be improved.

  One feature of the present invention is that in the above-described feature of the present invention, the method has a step of forming a plurality of recesses in the first thermoplastic resin layer. In the step (B), each of the recesses is provided. The gist is to arrange each of the plurality of solar cells.

  According to this feature, a recess is formed on the first thermoplastic resin layer, and the solar battery cell is disposed with the light receiving surface facing the recess. Therefore, after the solar cells are arranged, positioning restrictions in the step of electrically connecting the solar cells arranged in the first thermoplastic resin layer to each other by the wiring material are moderated. In addition, it is possible to improve yield reduction during manufacturing. Thereby, productivity can be improved.

  According to the present invention, when a solar cell module is manufactured by connecting a plurality of solar cells with a wiring member only on the back surface side, the warpage of the solar cells is suppressed without using a new member, and at the time of lamination Yield reduction can be improved.

  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. Therefore, 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.

  The manufacturing method of the solar cell module shown as embodiment of this invention is from the photovoltaic cell which has the extraction structure of both the electrode of a p side electrode and an n side electrode in the back surface provided in the other side of the light-receiving surface into which light injects. It is effective as a method for manufacturing a solar cell module.

  A configuration of a solar cell module shown as an embodiment of the present invention will be described with reference to FIG.

  A solar cell module 1 shown in FIG. 1 includes a light receiving surface member 11 as a first protective member, a first resin layer 12, a plurality of solar cells 13, a second resin layer 15, and a second protective member. And are laminated in this order from the incident direction of light. The solar cells 13 are electrically connected to each other by the wiring material 14 on the back surface side, and are sealed between the light receiving surface member 11 and the back surface member 16 by the first resin layer 12 and the second resin layer 15. ing.

  The light receiving surface member 11 is a material having both insulating properties and translucency, such as glass and plastic. Further, it is a material that can transmit light in the ultraviolet region to the infrared region. Specific examples include various glasses, polycarbonates, acrylic resins, fluorine-based films, and PET-based films.

  As the resin for the first resin layer 12 and the second resin layer 15, thermoplastic resins such as ethylene vinyl acetate (EVA), thermoplastic silicone resin, thermoplastic fluororesin, and thermoplastic olefin resin can be used. Moreover, the combination of these resin may be sufficient. Further, the first resin layer 12 and the second resin layer 15 may be the same resin or different resins. The first resin layer 12 and the second resin layer 15 are obtained by processing these resins into a film shape.

  The back member 16 can be made of an insulating material such as glass or plastic. Specifically, various types of glass, polycarbonate, acrylic resin, fluorine-based film, PET-based film, or a metal substrate that has been subjected to insulation treatment on the light-receiving side surface can be used.

  The solar battery cell 13 has a crystalline semiconductor such as single crystal silicon or polycrystalline silicon. The solar cell 13 has an n-type region and a p-type region formed therein, and a semiconductor junction is formed at the interface between the n-type region and the p-type region. And it is a photovoltaic cell by which the collector electrode of the p side electrode and the n side electrode is provided in the back surface side. In addition to this, the solar battery cell 13 has a substantially intrinsic amorphous silicon layer sandwiched between the single crystal silicon substrate and the amorphous silicon layer to reduce defects at the interface, and the characteristics of the heterojunction interface. It may be a solar battery cell having an improved structure, a so-called HIT structure. The solar battery cell 13 may be a solar battery cell in which both the p-side electrode and the n-side electrode take-out structure are provided on the back surface side. For example, by providing a through hole in the semiconductor substrate, the solar cell 13 can collect the light receiving surface and the back surface. A through-hole type in which electricity is provided by a wiring material disposed on the back surface side, or a so-called back contact type in which p-doped regions and n-doped regions are alternately provided on the back surface side with respect to the light receiving surface can be applied.

  Next, the manufacturing method of the solar cell module shown as 1st Embodiment of this invention is demonstrated with reference to Fig.2 (a)-(e).

  As shown in FIG. 2A, the first resin layer 12 is disposed on the light receiving surface member 11 in the solar cell module manufacturing method of the present embodiment. Subsequently, as shown in FIG. 2B, the solar battery cell 13 is arranged with the first resin layer 12 and the light receiving surface of the solar battery cell 13 facing each other. Subsequently, in a state where the solar cells 13 are arranged on the first resin layer 12 so that the light receiving surfaces are opposed to each other, the first resin layer 12 is heated to a temperature corresponding to the melting temperature, so that the solar cells 13 are heated to the first resin layer 12. (FIG. 2 (c)).

  After the crimping, the adjacent solar cells 13 are electrically connected to each other by the wiring member 14 as shown in FIG. After connecting the solar cells 13 with the wiring material 14, the second resin layer 15 is formed on the back surface of the solar cells 13. And as shown in FIG.2 (e), the back surface member 16 is arrange | positioned on the 2nd resin layer 15, and it seals. In this sealing step, the first resin layer 12 and the second resin layer 15 are dissolved under conditions such as appropriately adjusted temperature, vacuum degree, pressure, etc., so that the light receiving surface member 11, the solar battery cell 13, and the back surface member. 16 are glued together.

  According to the method for manufacturing the solar cell module shown as the first embodiment, before the p-side electrode and the n-side electrode extraction structure formed on the back surface of the solar cell 13 are electrically connected to each other by the wiring member 14. In addition, the solar battery cell 13 can be fixed to the first resin layer 12. Therefore, the curvature of the photovoltaic cell 13 when connecting the wiring member 14 can be suppressed without using a new member. Thereby, in a sealing process, the yield fall resulting from cell curvature can be improved. Therefore, productivity at the time of manufacturing the solar cell module can be improved.

  Next, the manufacturing method of the solar cell module shown as 2nd Embodiment of this invention is demonstrated with reference to Fig.3 (a)-(e). The method for manufacturing a solar cell module shown as the second embodiment includes a step of forming a recess to such an extent that the solar cell 13 can be embedded in the first resin layer 12, and the solar cell 13 is provided in each of the recesses. The point to mount is a feature.

  As shown to Fig.3 (a), in the manufacturing method of the solar cell module shown as 2nd Embodiment, the 1st resin layer 12 is formed on the light-receiving surface member 11. As shown in FIG. Subsequently, as shown in FIG. 3 (b), the stamper 21 forms a recess having substantially the same shape as the planar shape of the solar battery cell 13 in the first resin layer 12.

  The stamper head of the stamper 21 has a heating mechanism, and can form the recess 12 a while melting the first resin layer 12. The depth of the recess 12a is a depth that takes into account the thickness of the solar battery cell, the thickness of the collector electrode formed on both surfaces of the solar battery cell 13, and the amount of penetration due to pressure bonding. In this step, if the back surface of the solar battery cell 13 is lower than the first resin layer 12a, a step is formed on the surface to which the wiring member 14 is connected, so that a problem occurs in the step of connecting the wiring member 14. For example, when the wafer thickness is 100 μm and the height of the collecting electrode (finger electrode) from the wafer surface is 50 μm, it is preferable to form a recess having a depth of about 150 μm.

  Next, as shown in FIG. 3C, the solar battery cell 13 is placed with the light receiving surface facing the recess 12 a on the first resin layer 12. Subsequently, in a state where the solar battery cell 13 is placed with the light receiving surface facing the concave portion 12a, the first resin layer 12 is heated to a temperature corresponding to the melting temperature, and the solar battery cell 13 is pressure-bonded to the first resin layer 12 ( (Refer FIG.3 (d)).

  After the crimping, the adjacent solar cells 13 are electrically connected to each other by the wiring member 14 (see FIG. 3E). After connecting the solar cells 13 with the wiring material 14, the second resin layer 15 is formed on the back surface of the solar cells 13, and the back member 16 is disposed on the second resin layer 15 and sealed (FIG. 3 (f)).

  According to the solar cell module manufacturing method shown as the second embodiment described above, the p-side electrode and the n-side electrode extraction structure formed on the back surface of the solar cell 13 are electrically connected to each other by the wiring member 14. Before the solar cell 13 can be fixed to the first resin layer 12. Therefore, the curvature of the photovoltaic cell 13 when connecting the wiring member 14 can be suppressed without using a new member. Thereby, in a sealing process, the yield fall resulting from cell curvature can be improved. Therefore, productivity at the time of manufacturing the solar cell module can be improved.

  Moreover, according to the manufacturing method of the solar cell module shown as 2nd Embodiment, the positioning of the photovoltaic cell 13 becomes easy by forming the recessed part 12a in the 1st resin layer 12, and making it into the recessed part 12a. Further, by forming the recess 12a, it is possible to relieve stress from the first adhesive layer 12 that is received when the solar battery cell 13 is pressed against the first resin layer 12 during pressure bonding. Thereby, the cell crack in the process of fixing the photovoltaic cell 13 to the 1st resin layer 12 can be suppressed.

  FIG. 4: shows sectional drawing after the sealing process of the solar cell module manufactured by the manufacturing method of the solar cell module shown as 1st Embodiment or 2nd Embodiment. The solar cell module 1 has a structure in which the solar cells 13 are sandwiched between the light receiving surface member 11 and the back surface member 16 via the first resin layer 12 and the second resin layer 15 after sealing. Thereby, the influence of the water | moisture content from outside and an ultraviolet-ray can be suppressed to the minimum. Moreover, since the solar cell module 1 does not use a new member, the number of parts can be reduced. Thereby, cost reduction can be achieved.

  It should be noted that the present invention can be modified in various ways without departing from the gist of the present invention described above, and the description and drawings that constitute a part of this disclosure do not limit the present invention. For example, as for the thickness of the photovoltaic cell 13 which can be used in the manufacturing method of the solar cell module shown as 1st Embodiment and 2nd Embodiment, 50-500 micrometers is preferable. More preferably, it is 100-200 micrometers. It is effective for use in thinned solar cells. Moreover, when an EVA film is used as the first resin layer 12, the temperature of the system is raised to about 180 ° C. as an example in the step of pressure bonding the solar battery cell 13.

  Moreover, although embodiment of this invention demonstrated each process at the time of manufacturing a solar cell module, the case where a row (what is called a string) of a solar cell module may be manufactured.

It is a disassembled perspective view explaining the solar cell module manufactured by the manufacturing method of the solar cell module shown as embodiment of this invention. It is a schematic diagram explaining the manufacturing method of the solar cell module shown as 1st Embodiment of this invention. It is a schematic diagram explaining the manufacturing method of the solar cell module shown as 2nd Embodiment of this invention. It is a disassembled perspective view explaining the solar cell module manufactured by the manufacturing method of the solar cell module shown as embodiment of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Solar cell module, 11 ... Light-receiving surface member, 12 ... 1st resin layer, 13 ... Solar cell, 14 ... Wiring material, 15 ... 2nd resin layer, 16 ... Back surface member

Claims (2)

A manufacturing method for manufacturing a solar cell module by connecting a plurality of solar cells having a light receiving surface for receiving light and a back surface provided on the opposite side of the light receiving surface by a wiring member only on the back surface side. ,
A step (A) of disposing a first thermoplastic resin layer on the first protective member;
A step (B) of disposing the solar battery cell on the first thermoplastic resin layer with the surface of the first thermoplastic resin layer facing the light receiving surface of the solar battery cell;
The first thermoplastic resin layer is heated to the melting temperature of the first thermoplastic resin layer, and the solar battery cell disposed in the first thermoplastic resin layer is pressure-bonded to the first thermoplastic resin layer. Step (C) to perform,
A step (D) of electrically connecting the solar cells arranged in the first thermoplastic resin layer to each other by the wiring material;
A step (E) of disposing the second thermoplastic resin layer on the plurality of solar cells;
A step (F) of disposing a second protective member on the second thermoplastic resin layer. Forming a plurality of recesses in the first thermoplastic resin layer;
2. The method of manufacturing a solar cell module according to claim 1, wherein in the step (B), each of the plurality of solar cells is disposed in each of the recesses.

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