JP2011003938A - Solar cell and solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell in which an effect of a contractile force of a wiring material on the solar cell is reduced, and to provide a solar cell module having the same.SOLUTION: The solar cell has first and second photoelectric conversion part side electrically-conducting connection parts on its back surface, and an insulator has first and second insulator side electrically-conducting connection parts on a first major surface, and the first insulator side electrically-conducting connection parts are electrically connected to the first photoelectric conversion part side electrically-conducting connection parts by bonding the first major surface of the insulator to the back surface of the solar cell with an anisotropic conductive adhesive, and the second insulator side electrically-conducting connection parts are electrically connected to the second photoelectric conversion part side electrically-conducting connection parts, and the first and the second insulator side electrically-conducting connection parts of the insulator are electrically connected to wiring mounted to a second major surface at the opposite side of the first major surface of the insulator via through-holes formed at the insulator.

Description

  The present invention relates to a solar cell in which a wiring member is thermally bonded only on the back surface side and a solar cell module including the solar cell.

  Solar cells directly convert clean and inexhaustible sunlight into electricity. Therefore, solar cells are expected as a new energy source.

  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 in which a plurality of solar cells are alternately connected by a wiring material is used.

  Generally, a solar cell includes a pair of positive and negative electrodes formed on a light receiving surface that receives sunlight and a back surface provided on the opposite side of the light receiving surface. The wiring member is thermally bonded to an electrode formed on the light receiving surface of one solar cell and an electrode formed on the back surface of another solar cell adjacent to the one solar cell (see, for example, Patent Document 1). .

  Here, since the linear expansion coefficient of the wiring material is larger than the linear expansion coefficient of the semiconductor substrate constituting the solar cell, a force that causes the wiring material to contract after thermal bonding is generated at the interface between the wiring material and the solar cell. .

  As described above, when the wiring material is thermally bonded to the light receiving surface and the back surface of the solar cell, the shrinkage force is applied to the solar cell from both the light receiving surface and the back surface. Is done.

JP 2005-217148 A

  Here, the electrical output of the solar cell is substantially proportional to the light receiving area on the light receiving surface. Therefore, it is considered that the light receiving area of the solar cell can be increased by forming a pair of positive and negative electrodes on the back surface of the solar cell and providing the wiring member on the back surface side of the solar cell.

  Specifically, one wiring material is thermally bonded to a positive electrode formed on the back surface of one solar cell and a negative electrode formed on the back surface of another solar cell adjacent to the one solar cell. Similarly, another wiring material is thermally bonded to the negative electrode formed on the back surface of one solar cell and the positive electrode formed on the back surface of another solar cell adjacent to the one solar cell.

  Thus, when the wiring material is thermally bonded only to the back surface side of the solar cell, the shrinkage force of the wiring material is applied only to the back surface of the solar cell, so that the solar cell may be warped.

  In particular, it is considered that such warpage of the solar cell is more prominent as the solar cell becomes thinner for the purpose of reducing the manufacturing cost. Therefore, thermally bonding the wiring member only to the back surface side of the solar cell also hinders the thinning of the solar cell.

  Therefore, the present invention has been made in view of the above problems, and in the case where the wiring material is thermally bonded only to the back side of the solar cell, the solar cell and the solar cell in which the influence of the shrinkage force of the wiring material is reduced It aims at providing a solar cell module provided with.

  A solar cell module according to one aspect of the present invention is a solar cell module in which electrical connection of a plurality of solar cells is performed on the back side of an insulator disposed on the back side of the solar cell, and the solar cell Has first and second photoelectric conversion unit side conductive connection portions on the back surface, and the insulator has first and second insulator side conductive connection portions on the first main surface, and is formed by anisotropic conductive adhesive. By joining the first main surface of the insulator to the back surface of the solar cell, the first insulator-side conductive connection portion is electrically connected to the first photoelectric conversion unit-side conductive connection portion, and the second insulation The body-side conductive connection portion is electrically connected to the second photoelectric conversion portion-side conductive connection portion, and the first insulator-side conductive connection portion and the second insulator-side conductive connection portion of the insulator are provided in the insulator. Facing the first main surface of the insulator through the formed through hole That is electrically connected to the wiring provided on the second major surface and gist.

  According to the present invention, it is possible to provide a solar cell and a solar cell module in which the influence of the shrinkage force of the wiring material is reduced when the wiring material is thermally bonded only to the back surface side of the solar cell.

It is a side view of the solar cell module 1 which concerns on 1st Embodiment. It is a rear view of the solar cell string 101 which concerns on 1st Embodiment. It is a top view of the solar cell string 101 which concerns on 1st Embodiment. It is sectional drawing in the AA of FIG. It is sectional drawing in the BB line of FIG. It is sectional drawing in CC line of FIG. It is a rear view of the solar cell string 102 which concerns on 2nd Embodiment. It is a rear view of the insulator 14 which concerns on 2nd Embodiment. It is sectional drawing in the DD line | wire of FIG. It is a rear view of the solar cell string 103 which concerns on 3rd Embodiment. It is a rear view of the insulator 14 which concerns on 3rd Embodiment. It is a rear view of the solar cell 10a and the solar cell 10b which concern on 3rd Embodiment. It is sectional drawing in the EE line | wire of FIG. It is a side view which shows the solar cell module 2 which concerns on 4th Embodiment. It is a rear view of the solar cell string 104 which concerns on 4th Embodiment. It is a top view of the solar cell string 104 which concerns on 4th Embodiment. It is an expanded sectional view in the FF line of FIG. It is a rear view of the solar cell string 105 which concerns on 5th Embodiment. It is a top view of the solar cell string 105 which concerns on 5th Embodiment. It is a rear view of the solar cell 10d which concerns on 5th Embodiment. It is an expanded sectional view in the GG line of FIG. It is an expanded sectional view in the HH line of FIG. It is a rear view of the solar cell string 106 which concerns on 6th Embodiment. It is a rear view of the solar cell 10e which concerns on 6th Embodiment. (A) is a rear view of the insulator 114 according to the sixth embodiment. (B) is a top view of the insulator 114 according to the sixth embodiment. It is an expanded sectional view in the II line of FIG. It is a rear view of the solar cell string 107 which concerns on 7th Embodiment. It is a top view of the solar cell string 107 which concerns on 7th Embodiment. It is a rear view of the solar cell 10f which concerns on 7th Embodiment. It is an expanded sectional view in the JJ line of FIG. It is an expanded sectional view in the KK line of FIG. It is an expanded sectional view in the LL line of FIG.

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]
(Configuration of solar cell module)
The configuration of the solar cell module according to the first embodiment will be described with reference to FIG. FIG. 1 is a side view showing the solar cell module 1 according to the first embodiment.

  As shown in FIG. 1, the solar cell module 1 includes a solar cell string 101, a light receiving surface side protective material 11, a back surface side protective material 12, and a sealing material 13.

  The solar cell string 101 includes a plurality of solar cells 10 and a wiring material 15. As shown in FIG. 1, the plurality of solar cells 10 includes solar cells 10 a and solar cells 10 b that are alternately arranged along the arrangement direction. The solar cell 10a and the solar cell 10b are electrically connected to each other in series by the wiring member 15. In the first embodiment, the solar cell 10 a and the solar cell 10 b share the insulator 14. The configuration of the insulator 14 will be described later.

  The light-receiving surface side protective material 11 is disposed on the upper surface side of the solar cell module 1. The light receiving surface side protection member 11 protects the light receiving surface side of the plurality of solar cells 10. The light-receiving surface side protective material 11 can be formed of glass or plastic having translucency and weather resistance.

  The back surface side protective material 12 is disposed on the back surface side of the solar cell module 1. The back surface side protective material 12 protects the back surface side of the plurality of solar cells 10. The back surface side protective material 12 can be formed by a weather resistant glass, plastic, resin film monolayer, or a laminate in which a metal foil is sandwiched between resin films.

  The sealing material 13 seals the plurality of solar cells 10 between the light receiving surface side protective material 11 and the back surface side protective material 12. The sealing material 13 can be formed of a translucent resin such as EVA, EEA, or PVB.

(Configuration of solar cell string)
FIG. 2 is a rear view of the solar cell string 101. FIG. 3 is a top view of the solar cell string 101.

  The solar cell string 101 includes a solar cell 10 a, a solar cell 10 b, and a wiring member 15.

  As shown in FIGS. 2 and 3, each of the solar cell 10a and the solar cell 10b includes a photoelectric conversion unit 20, a first collector electrode 30, a second collector electrode 35, a plurality of first through-hole electrodes 23, and a plurality of A second through-hole electrode 25 is provided. In the first embodiment, each of the solar cell 10a and the solar cell 10b shares the insulator 14.

  Here, the solar cell 10a and the solar cell 10b have the same configuration as shown in FIGS. The difference between the solar cell 10a and the solar cell 10b is that they are half-rotated (rotated 180 degrees) around the axis passing through the center of the light receiving surface.

  The photoelectric conversion unit 20 has a light receiving surface that receives light and a back surface provided on the opposite side of the light receiving surface. The photoelectric conversion unit 20 has a semiconductor junction such as a semiconductor pn junction or a semiconductor pin junction as a basic structure. The photoelectric conversion unit 20 generates photogenerated carriers by receiving light. The photogenerated carrier refers to holes and electrons generated when sunlight is absorbed by the photoelectric conversion unit 20. The detailed configuration of the photoelectric conversion unit 20 will be described later.

  The first current collecting electrode 30 is formed on the light receiving surface of the photoelectric conversion unit 20. The first current collecting electrode 30 collects the photogenerated carriers generated by the photoelectric conversion unit 20 from the photoelectric conversion unit 20. The first current collecting electrode 30 can be formed of a thermosetting resin paste, a so-called ceramic paste, or the like.

  The second current collecting electrode 35 is formed on the back surface of the photoelectric conversion unit 20. The second collecting electrode 35 collects the photogenerated carriers generated by the photoelectric conversion unit 20 from the photoelectric conversion unit 20. The second current collecting electrode 35 can be formed of a thermosetting resin paste, a so-called ceramic paste, or the like.

  The first through-hole electrode 23 penetrates the photoelectric conversion unit 20 and the insulator 14 (see FIG. 4). One end of the first through-hole electrode 23 is electrically connected to the first current collecting electrode 30. The other end of the first through-hole electrode 23 is electrically connected to the wiring member 15. The first through-hole electrode 23 can be formed of a thermosetting resin paste or a so-called ceramic paste. In the first embodiment, three first through-hole electrodes 23 are provided along the arrangement direction. Such three first through-hole electrodes 23 are provided in two rows in the orthogonal direction.

  The second through-hole electrode 25 penetrates the insulator 14 (see FIG. 4). The first through-hole electrodes 23 and the second through-hole electrodes 25 are provided alternately along the orthogonal direction. One end of the second through-hole electrode 25 is electrically connected to the second current collecting electrode 35. The other end of the second through-hole electrode 25 is electrically connected to the wiring material 15. The second through-hole electrode 25 can be formed of a thermosetting resin paste or a so-called ceramic paste. In the first embodiment, three second through-hole electrodes 25 are provided along the arrangement direction. Such three second through-hole electrodes 25 are provided in two rows in the orthogonal direction.

  As shown in FIG. 3, the three first through-hole electrodes 23 of the solar cell 10a and the three second through-hole electrodes 25 of the solar cell 10b are provided on a straight line. Similarly, the three second through-hole electrodes 25 of the solar cell 10a and the three first through-hole electrodes 23 of the solar cell 10b are provided on a straight line.

  The insulator 14 is made of a material having electrical insulation. The insulator 14 is formed in a flat plate shape. The insulator 14 is arrange | positioned so that the back surface of the photoelectric conversion part 20 which each of the solar cell 10a and the solar cell 10b has may be covered. The insulator 14 has a first main surface 14A facing the back surface of the photoelectric conversion unit 20 and a second main surface 14B provided on the opposite side of the first main surface 14A. Therefore, the 2nd main surface 14B forms the back of solar cell 10a and solar cell 10b.

  Here, the material constituting the insulator 14 is preferably selected according to the purpose of use of the insulator 14. Hereinafter, each main purpose of use of the insulator 14 will be described.

(1) Suppressing deformation of solar cell 10 When the insulator 14 is used to suppress deformation of the solar cell 10, the insulator 14 is made of a material having a high Young's modulus (high resistance to external force). It is preferable. Specifically, the insulator 14 can be formed of a thermosetting resin material such as an epoxy resin or an inorganic material such as ceramic.

    When a resin material is used as the insulator 14, the insulator 14 exhibits adhesiveness by heating, and thus the insulator 14 can be bonded to the photoelectric conversion unit 20 without using a conductive adhesive or the like. On the other hand, when an inorganic material is used as the insulator 14, the insulator 14 is bonded to the solar cell 10 with a conductive adhesive or the like.

(2) Relieving the shrinkage force of the wiring material 15 When the insulator 14 is used to relieve the shrinkage force or expansion force of the wiring material 15 in response to a temperature change, a flexible resin such as silicone or EVA It is preferable that the insulator 14 is made of a material. The contraction force and expansion force of the wiring member 15 are absorbed by the insulator 14 having flexibility.

(3) Reflecting or scattering incident light The insulator 14 preferably has a function of reflecting or scattering incident light. By using such an insulator 14, incident light can be efficiently guided to the solar cell 10. Such a function can be obtained by forming the insulator 14 using a resin material in which a plurality of particles are mixed, or performing mechanical processing such as prism processing or other surface processing. Specifically, particles composed of titanium oxide, silicon dioxide, or the like can be used as the plurality of particles. Further, when EVA is used as the insulator 14, the EVA itself can be subjected to fine prism processing.

(4) Ensuring insulation between the wiring member 15 and the solar cell 10 In order to sufficiently suppress a short circuit between the wiring member 15 and the solar cell 10, the surface of the insulator 14 is coated with a resin material having high insulation characteristics. It is preferable. As such a coating material, imide, amide, polyimide, polyamide, polysilazane, or the like can be used.

  As shown in FIG. 3, the wiring member 15 is disposed on the second main surface 14 </ b> B of the insulator 14 along the arrangement direction. The wiring member 15 electrically connects the solar cell 10a and the solar cell 10b. The wiring member 15 can be formed of a conductive material such as copper formed into a thin plate shape or a twisted wire shape. Note that the surface of the wiring member 15 may be plated with solder.

  Here, the wiring member 15 is electrically connected to the three first through-hole electrodes 23 included in the solar cell 10a and the three second through-hole electrodes 25 included in the solar cell 10b. Similarly, the wiring member 15 is electrically connected to the three second through-hole electrodes 25 included in the solar cell 10a and the three first through-hole electrodes 23 included in the solar cell 10b. Thereby, the solar cell 10a and the solar cell 10b are electrically connected in series.

(Configuration of solar cell)
Next, the configuration of the solar cell 10a and the solar cell 10b will be described with reference to the drawings. 4 is a cross-sectional view taken along line AA in FIG. 5 is a cross-sectional view taken along line BB in FIG. 6 is a cross-sectional view taken along the line CC of FIG.

  As shown in FIGS. 4-6, the photoelectric conversion part 20 has the semiconductor substrate 20a, the 1st semiconductor layer 20b, the transparent conductive film 20c, the 2nd semiconductor layer 20d, and the transparent conductive film 20e.

  The semiconductor substrate 20a can be formed of a crystalline semiconductor material such as single crystal Si or polycrystalline Si, or a compound semiconductor material such as GaAs or InP.

  The first semiconductor layer 20b and the second semiconductor layer 20d have different conductivity types. The transparent conductive films 20c and 20e can be formed using ITO (Indium Tin Oxide) or the like.

  Note that the photoelectric conversion unit 20 may have a so-called HIT structure in which a substantially intrinsic amorphous silicon layer is sandwiched between a single crystal silicon substrate and an amorphous silicon layer.

  As shown in FIG. 4, the first through-hole electrode 23 penetrates from the light receiving surface of the photoelectric conversion unit 20 to the second main surface 14 </ b> B of the insulator 14. The first through-hole electrode 23 is formed in a column shape, and the column surface of the first through-hole electrode 23 is covered with an insulating layer 24. One end of the first through-hole electrode 23 is electrically connected to the first current collecting electrode 30 on the light receiving surface of the photoelectric conversion unit 20. The other end of the first through-hole electrode 23 is electrically connected to the wiring member 15 on the second main surface 14B of the insulator 14. A conductive adhesive 26 is interposed between the first through-hole electrode 23 and the wiring member 15. As such a conductive adhesive 26, a resin adhesive or solder containing conductive metal particles or the like can be used.

  The insulating layer 24 can be formed of a known insulating material. The insulating layer 24 electrically separates the first through-hole electrode 23 and the photoelectric conversion unit 20. Note that the insulating layer 24 may not be formed between the first through-hole electrode 23 and the insulator 14.

  As shown in FIG. 4, the second through-hole electrode 25 penetrates from the first main surface 14A to the second main surface 14B of the insulator 14. One end of the second through-hole electrode 25 is electrically connected to the second current collecting electrode 35 on the back surface of the photoelectric conversion unit 20. The other end of the second through-hole electrode 25 is electrically connected to the wiring member 15 on the second main surface 14B of the insulator 14. A conductive adhesive 26 is interposed between the second through-hole electrode 25 and the wiring member 15.

  As shown in FIG. 6, a conductive adhesive 26 is provided between the insulator 14 and the wiring member 15 along the arrangement direction. As a result, the wiring member 15 is firmly bonded to the second main surface 14B of the insulator 14.

  4 to 6 show a case where the insulator 14 is made of a resin material such as silicone or EVA. Therefore, no adhesive or the like is provided between the insulator 14 and the solar cell 10.

(Method for manufacturing solar cell module)
Next, an example of a method for manufacturing the solar cell module 1 will be described.

  First, the first semiconductor layer 20b and the second semiconductor layer 20d are formed on the semiconductor substrate 20a by using a CVD method or the like.

  Next, an ITO film (transparent conductive film 20c) is formed on the first semiconductor layer 20b by using a sputtering method or the like. Similarly, an ITO film (transparent conductive film 20e) is formed on the second semiconductor layer 20d. Thereby, the photoelectric conversion part 20 is formed.

  Next, a thermosetting conductive paste is printed in a predetermined pattern on the light receiving surface and the back surface of the photoelectric conversion unit 20 using a printing method such as a screen printing method. Thereby, the 1st current collection electrode 30 and the 2nd current collection electrode 35 are formed. As the conductive paste, an epoxy thermosetting silver paste or the like can be used.

  Next, the photoelectric conversion units 20 on which the first current collecting electrode 30 and the second current collecting electrode 35 are formed are arranged along the arrangement direction while being rotated halfway.

  Next, a resin sheet (insulator 14) is disposed on the back surfaces of the two photoelectric conversion units 20. Then, by using a CO2 laser or an excimer laser, two rows of three first through holes penetrating the photoelectric conversion unit 20 and the resin sheet are formed along the arrangement direction. Similarly, two rows of three second through holes penetrating the resin sheet are formed along the arrangement direction. At this time, the first through holes and the second through holes are alternately formed in the orthogonal direction.

  Next, an insulating material such as polysilazane is applied to the inner wall of the first through hole. Thereby, an insulation process (insulating layer 24) is given to the inner wall of the first through hole.

  Next, using a printing method such as a screen printing method, the six first through holes and the six second through holes are filled with a thermosetting conductive paste. As the conductive paste, an epoxy thermosetting silver paste or the like can be used. Thus, six first through-hole electrodes 23 and six second through-hole electrodes 25 are formed, and the solar cell 10a and the solar cell 10b are manufactured.

  Next, the wiring member 15 is thermally bonded to the three first through-hole electrodes 23 of the solar cell 10 a and the three second through-hole electrodes 25 of the solar cell 10 b through the conductive adhesive 26. Similarly, the wiring member 15 is thermally bonded to the three second through-hole electrodes 25 of the solar cell 10 a and the three first through-hole electrodes 23 of the solar cell 10 b through the conductive adhesive 26. Thereby, the solar cell string 101 is produced.

  Next, an EVA sheet (sealing material 13), a solar cell string 101, an EVA sheet (sealing material 13), and a PET film (back surface side protection material 12) are sequentially formed on a glass substrate (light-receiving surface side protection material 11). Laminate to make a laminate.

  Next, EVA is crosslinked by heat-pressing the laminate in a vacuum atmosphere. Thus, the solar cell module 1 is manufactured. Note that a terminal box, an Al frame, or the like can be attached to the solar cell module 1.

(Function and effect)
In 1st Embodiment, each of the solar cell 10a and the solar cell 10b has the insulator 14 joined to the back surface of the photoelectric conversion part 20.

  Therefore, the contraction force or expansion force of the wiring member 15 according to the temperature change can be absorbed by the insulator 14. Therefore, it is possible to suppress the warpage of the photoelectric conversion unit 20 due to the contraction force or expansion force of the wiring member 15. Therefore, it can suppress that a crack and a chip | tip generate | occur | produce in the solar cell 10a and the solar cell 10b.

  Moreover, the solar cell 10a and the solar cell 10b share the insulator 14 integrally formed in flat form. Therefore, in the modularization process, it is possible to prevent stress from concentrating on the end portions in the arrangement direction of the solar cells 10a and 10b. Therefore, it can suppress that a crack generate | occur | produces in each edge part of the solar cell 10a and the solar cell 10b.

  Further, when the insulator 14 is formed of a resin material containing a plurality of particles, or when the insulator 14 is subjected to surface processing for scattering light, the incident light is reflected or scattered by the insulator 14. Can be made. Therefore, more incident light can be guided to the solar cell 10a and the solar cell 10b. This is effective for a double-sided solar cell that also uses incident light from the back surface of the photoelectric conversion unit 20. Further, as the solar cell becomes thinner, the light transmitted through the solar cell itself increases. Therefore, it is particularly effective for a thin double-sided power generation type solar cell that the insulator 14 has a function of reflecting or scattering incident light.

  Further, when the insulator 14 is formed of a resin material containing a plurality of particles, the bonding of the resin material is divided by the plurality of particles. As a result, the bonding of the resin material is weakened, so that the external force can be more absorbed by the insulator 14.

[Second Embodiment]
A second embodiment will be described with reference to FIGS. In the second embodiment, a through hole and a conductor (wiring material) are provided in advance in the insulator. In the following description, description of the same or similar parts as in the first embodiment will be omitted.

(Configuration of solar cell string)
FIG. 7 is a rear view of the solar cell string 102 according to the present embodiment. As shown in FIG. 7, the first through-hole electrode 23 (or the second through-hole electrode 25) of the solar cell 10a and the second through-hole electrode 25 (or the first through-hole electrode 23) of the solar cell 10b are as follows. Are electrically connected through the conductor 15a.

(Insulator structure)
FIG. 8 is a rear view of the insulator 14 according to the second embodiment. The insulator 14 is provided with a first insulator through hole 27a, a second insulator through hole 27b, and a conductor 15a.

  Each of the first insulator through hole 27a and the second insulator through hole 27b penetrates from the first main surface 14A of the insulator 14 to the second main surface 14B. The first through-hole electrode 23 is formed in the first insulator through hole 27a. A second through-hole electrode 25 is formed in the second insulator through hole 27b.

  The conductor 15a is formed on the second main surface 14B of the insulator 14. The conductor 15a is provided so as to connect the first insulator through holes 27a or the second insulator through holes 27b along the arrangement direction. The conductor 15a can be formed of the same material as the wiring member 15 described in the first embodiment. In addition, in 2nd Embodiment, although the conductor 15a is joined on the insulator 14, the conductor 15a may be engage | inserted by the insulator 14. FIG.

(Configuration of solar cell)
9 is a cross-sectional view taken along the line DD of FIG. As shown in FIG. 9, the solar cell 10a and the solar cell 10b have the same configuration as in the first embodiment. The first through-hole electrode 23 is formed in the first insulator through hole 27a by being filled with a conductive material. The second through-hole electrode 25 is formed in the second insulator through hole 27b by being filled with a conductive material. Solar cell 10a and solar cell 10b are electrically connected in series by conductor 15a.

(Method for manufacturing solar cell)
Next, the manufacturing method of the solar cell 10a and the solar cell 10b which concerns on this embodiment is demonstrated.

  First, the photoelectric conversion units 20 on which the first current collecting electrode 30 and the second current collecting electrode 35 are formed are arranged along the arrangement direction while being half-rotated from each other.

  Next, the insulator 14 shown in FIG. 8 is disposed on the solar cell 10a and the solar cell 10b.

  Next, a through hole is formed in the photoelectric conversion unit 20 by irradiating the inside of the first insulator through hole 27a with a CO2 laser or an excimer laser from the second main surface 14B side.

  Next, an insulating process (insulating layer 24) is performed by applying an insulating material such as polysilazane to the inner wall of the first through hole.

  Next, the first through hole and the second insulator through hole 27b are filled with a thermosetting conductive paste using a printing method such as a screen printing method. Thereby, the first through-hole electrode 23 and the second through-hole electrode 25 are formed.

  In addition, the manufacturing method of a solar cell module is the same as that of 1st Embodiment.

(Function and effect)
In the second embodiment, a first insulator through hole 27a and a second insulator through hole 27b are formed in the insulator 14 in advance.

  Therefore, when the insulator 14 is disposed on the solar cell 10a and the solar cell 10b, the position where the first through-hole electrode 23 and the second through-hole electrode are formed can be easily specified. Therefore, a through hole can be formed in the photoelectric conversion unit 20 using the position of the first insulator through hole 27a as a mark.

  In the second embodiment, the insulator 14 is provided with a conductor 15a. The conductor 15a is formed so as to connect the first insulator through holes 27a or the second insulator through holes 27b.

  Therefore, the solar cell 10a and the solar cell 10b can be electrically connected by filling the first insulator through hole 27a and the second insulator through hole 27b with the conductive material. The step of thermally bonding the wiring material onto the second main surface 14B of the insulator 14 can be omitted.

[Third embodiment]
Hereinafter, a third embodiment will be described with reference to the drawings. In the third embodiment, a conductive material is filled in the through holes formed in the insulator 14 in advance. In the following description, description of the same or similar parts as those of the second embodiment is omitted.

(Configuration of solar cell string)
FIG. 10 is a rear view of the solar cell string 103 according to the third embodiment. As shown in FIG. 10, the solar cell string 103 according to the third embodiment has the same configuration as the solar cell string 102 according to the second embodiment.

(Insulator structure)
FIG. 11 is a rear view of the insulator 14 according to the third embodiment. The insulator 14 is provided with a first insulator-side conductive portion 23a, a second insulator-side conductive portion 25a, and a conductor 15a.

  The first insulator-side conductive portion 23a is filled in a through-hole that penetrates from the first main surface 14A to the second main surface 14B of the insulator 14 (the first insulator through-hole 27a of the second embodiment, see FIG. 8). ing. The first insulator-side conductive portion 23a constitutes a part of the first through-hole electrode 23, as will be described later. The first insulator-side conductive portion 23a can be formed of a thermosetting conductive paste, a so-called ceramic paste, or the like.

  The second insulator-side conductive portion 25a is filled in a through hole (second insulator through hole 27b of the second embodiment, see FIG. 8) penetrating from the first main surface 14A to the second main surface 14B of the insulator 14. ing. The second insulator-side conductive portion 25a can be formed of the same material as that of the first insulator-side conductive portion 23a.

  The conductor 15a is disposed on the second main surface 14B of the insulator 14. The conductor 15a connects the first insulator-side conductive portions 23a or the second insulator-side conductive portions 25a along the arrangement direction. Therefore, the solar cell 10a and the solar cell 10b are electrically connected in series by the conductor 15a.

(Configuration of solar cell)
FIG. 12 is a rear view of the solar cells 10a and 10b according to the third embodiment. 13 is a cross-sectional view taken along line EE in FIG.

  As illustrated in FIG. 12, the solar cell 10 a and the solar cell 10 b include a photoelectric conversion unit side conductive unit 23 b and a second current collecting electrode 35.

  As illustrated in FIG. 13, the photoelectric conversion unit side conductive unit 23 b is provided in a through hole that penetrates from the light receiving surface to the back surface of the photoelectric conversion unit 20. The photoelectric conversion unit side conductive unit 23 b is electrically connected to the first insulator side conductive unit 23 a on the back side of the photoelectric conversion unit 20. In this way, the first through-hole electrode 23 is formed by electrically connecting the first insulator-side conductive portion 23a and the photoelectric conversion portion-side conductive portion 23b.

  As shown in FIG. 12, the second collector electrode 35 is electrically connected to the second insulator-side conductive portion 25 a in the region R. The second insulator-side conductive portion 25 a becomes the second through-hole electrode 25 by being connected to the second current collecting electrode 35.

  Thus, in the third embodiment, the first through-hole electrode 23 and the second through-hole electrode 25 are formed by bonding the insulator 14 to the photoelectric conversion unit 20.

  As shown in FIG. 13, the insulator 14 according to the third embodiment is joined to the photoelectric conversion unit 20 by an anisotropic conductive adhesive 28. As the anisotropic conductive adhesive 28, a resin adhesive containing a large number of conductive metal particles, so-called anisotropic conductive adhesive, can be used. Specifically, the anisotropic conductive adhesive 28 has conductivity in a direction substantially perpendicular to the first main surface 14A of the insulator 14. Therefore, the first insulator-side conductive portion 23a and the photoelectric conversion portion-side conductive portion 23b are electrically connected. On the other hand, the anisotropic conductive adhesive 28 has an insulating property in a direction substantially parallel to the first main surface 14A of the insulator 14. Accordingly, the first through-hole electrode 23 is electrically separated from the back surface of the photoelectric conversion unit 20, the second current collecting electrode 35, and the second through-hole electrode 25.

(Function and effect)
In the third embodiment, the first insulator-side conductive portion 23 a is formed in the insulator 14. A photoelectric conversion unit side conductive unit 23 b is formed in the photoelectric conversion unit 20.

  Therefore, the 1st through-hole electrode 23 can be formed by electrically connecting the 1st insulator side conductive part 23a and the photoelectric conversion part side conductive part 23b. That is, the first through-hole electrode 23 can be formed by bonding the insulator 14 and the photoelectric conversion unit 20. Therefore, the manufacturing process of the solar cell 10a and the solar cell 10b can be simplified.

  Further, the insulator 14 is formed with a second insulator-side conductive portion 25a. That is, the second through-hole electrode 25 is formed in the insulator 14 in advance. Therefore, the manufacturing process of the solar cell 10a and the solar cell 10b can be simplified.

  Further, the insulator 14 and the photoelectric conversion unit 20 are joined by an anisotropic conductive adhesive 28. The anisotropic conductive adhesive 28 has insulating properties in a direction parallel to the second main surface 14B of the insulator 14. Therefore, the insulator 14 and the photoelectric conversion part 20 can be easily joined, suppressing generation | occurrence | production of the short circuit inside the solar cell 10a and the solar cell 10b.

  Moreover, since the conductor 15a is provided in the insulator 14 in advance, as described in the first embodiment, the step of thermally bonding the wiring material on the second main surface 14B of the insulator 14 may be omitted. it can.

[Fourth embodiment]
(Schematic configuration of solar cell module)
Next, a schematic configuration of the solar cell module 2 according to the fourth embodiment of the present invention will be described with reference to the drawings. In the following description, description of the same or similar parts as those in the first embodiment is omitted.

  FIG. 14 is a side view showing the solar cell module 2 according to the fourth embodiment. As shown in FIG. 14, the solar cell module 2 includes a solar cell string 104, a light receiving surface side protective material 11, a back surface side protective material 12, and a sealing material 13.

  FIG. 15 is a rear view of the solar cell string 104. FIG. 16 is a top view of the solar cell string 104. As shown in FIGS. 15 and 16, the solar cell string 104 includes a plurality of solar cells 10 c and a wiring member 16.

  The plurality of solar cells 10c are arranged along the arrangement direction. The plurality of solar cells 10 c share the insulator 14. As the insulator 14, the same material as that of the first embodiment can be used.

  The wiring member 16 is disposed on the boundary portion between the two solar cells 10 c on the second main surface 14 </ b> B of the insulator 14. One end of the wiring member 16 is electrically connected to a first current collecting electrode 41 included in one solar cell 10c via a first through-hole electrode 43 described later. The other end of the wiring member 16 is electrically connected to a second collector electrode 42 of another solar cell 10c adjacent to the one solar cell 10c via a second through-hole electrode 45 described later. Thereby, each solar cell 10c is mutually electrically connected in series. The 1st current collection electrode 41 and the 2nd current collection electrode 42 are formed on the back of photoelectric conversion part 40 mentioned below.

(Configuration of solar cell)
Next, the configuration of the solar cell 10c will be described with reference to FIG. FIG. 17 is an enlarged cross-sectional view taken along line FF in FIG.

  The solar cell 10c includes the insulator 14, the photoelectric conversion unit 40, the first current collecting electrode 41, the second current collecting electrode 42, the first through-hole electrode 43, the first insulating layer 44, the second through-hole electrode 45, and the second. An insulating layer 46 is provided.

  The photoelectric conversion unit 40 has a light receiving surface (lower surface in FIG. 17) on which light is incident and a back surface (upper surface in FIG. 17) provided on the opposite side of the light receiving surface. The photoelectric conversion unit 40 generates a photogenerated carrier when light enters from the light receiving surface.

  The photoelectric conversion unit 40 has a semiconductor junction such as a semiconductor pn junction or a semiconductor pin junction as a basic structure. Specifically, as illustrated in FIG. 17, the photoelectric conversion unit 40 includes a semiconductor substrate 40a, a first semiconductor region 40b, and a second semiconductor region 40c. The semiconductor substrate 40a can be formed using a crystalline semiconductor material such as single crystal Si or polycrystalline Si, an amorphous Si alloy, or a thin film semiconductor material such as CuInSe. The first semiconductor region 40b and the second semiconductor region 40c have different conductivity types.

  The first current collecting electrode 41 is formed on the first semiconductor region 40 b in the back surface of the photoelectric conversion unit 40. The second current collecting electrode 42 is formed on the second semiconductor region 40 c in the back surface of the photoelectric conversion unit 40.

  The first through-hole electrode 43 penetrates from the first main surface 14A to the second main surface 14B of the insulator 14. One end of the first through-hole electrode 43 is electrically connected to the first current collecting electrode 41. The other end of the first through-hole electrode 43 is electrically connected to the wiring member 16 via the conductive adhesive 26. Although not shown, the first through-hole electrode 43 extends along an orthogonal direction that is substantially orthogonal to the arrangement direction.

  The first insulating layer 44 covers the outer periphery of the first through-hole electrode 43.

  The second through-hole electrode 45 penetrates from the first main surface 14A to the second main surface 14B of the insulator 14. One end of the second through-hole electrode 45 is electrically connected to the second current collecting electrode 42. The other end of the second through-hole electrode 45 is electrically connected to the wiring member 16 via the conductive adhesive 26. Although not shown, the second through-hole electrode 45 extends along the orthogonal direction.

  The conductive adhesive 26 is provided between the wiring material 16 and the first through-hole electrode 43 and between the wiring material 16 and the second through-hole electrode 45. As the conductive adhesive 26, it is possible to use a resin adhesive or solder containing conductive metal particles or the like.

(Function and effect)
In the fourth embodiment, each of the plurality of solar cells 10 c includes the insulator 14 bonded to the back surface of the photoelectric conversion unit 40.

  Therefore, the contraction force or expansion force of the wiring member 16 according to the temperature change can be absorbed by the insulator 14. Therefore, it is possible to suppress the warpage of the photoelectric conversion unit 40 due to the contraction force or expansion force of the wiring member 16. Therefore, it is possible to suppress the occurrence of cracks and chips in each solar cell 10c.

Moreover, the solar cell 10c according to the fourth embodiment is a so-called back junction solar cell in which the first semiconductor region 40b and the second semiconductor region 40c having different conductivity types are formed on the back surface side of the photoelectric conversion unit 40. is there. Therefore, since the current collecting electrode is not formed on the light receiving surface of the photoelectric conversion unit 40, the light receiving area can be enlarged.
[Fifth Embodiment]
Hereinafter, a fifth embodiment will be described with reference to the drawings. In the fifth embodiment, a wiring member extending in the orthogonal direction is provided on the insulator. In the following description, description of the same or similar parts as those in the first embodiment is omitted.

(Configuration of solar cell string)
FIG. 18 is a rear view of the solar cell string 105 according to the fifth embodiment. FIG. 19 is a top view of the solar cell string 105 according to the fifth embodiment.

  As shown in FIGS. 18 and 19, the solar cell string 105 includes a plurality of solar cells 10d, a first wiring member 115a, and a second wiring member 115b. The plurality of solar cells 10d are arranged along the arrangement direction. Each solar cell 10 d includes an insulator 114 and a third wiring member 115 c disposed on the insulator 114.

  The first wiring member 115a and the second wiring member 115b are disposed on the back surface of the solar cell 10d. Specifically, the first wiring member 115a and the second wiring member 115b are disposed on the second main surface 114B of the insulator 114 included in the solar cell 10d. A conductive adhesive 26 is provided between each of the first wiring member 115a and the second wiring member 115b and the second main surface 114B of the insulator 114 (see FIGS. 21 and 22).

  The first wiring member 115a and the second wiring member 115b are arranged along the arrangement direction on the back surface of the solar cell 10d. In the fifth embodiment, the two first wiring members 115a and the three second wiring members 115b are alternately arranged along the orthogonal direction. The two first wiring members 115a arranged on the back surface of the solar cell 10d extend toward the outside of the solar cell 10d.

  Here, as shown in FIG. 18, one end of each second wiring member 115b disposed on the back surface of one solar cell 10d is electrically connected to a third wiring member 115c included in one solar cell 10d. The One end of each first wiring member 115a disposed on the back surface of another solar cell 10d adjacent to one solar cell 10d is electrically connected to a third wiring member 115c included in the one solar cell 10d. Thereby, one solar cell 10d and another solar cell 10d are electrically connected in series.

  Accordingly, as shown in FIG. 19, when the solar cell string 105 is viewed from the upper surface side, the solar cells 10d are connected to each other by the two first wiring members 115a extending linearly along the arrangement direction. looks like. Thus, the solar cell string 105 according to the fifth embodiment has a more symmetrical configuration than the solar cell string 101 according to the first embodiment.

(Configuration of solar cell)
FIG. 20 is a rear view of the solar cell 10d. FIG. 21 is an enlarged cross-sectional view taken along line GG in FIG. 22 is an enlarged cross-sectional view taken along line HH in FIG.

  20 to 22, each solar cell 10d includes an insulator 114, a third wiring member 115c, a photoelectric conversion unit 20, a first through-hole electrode 23, an insulating layer 24, a second through-hole electrode 25, a first A collecting electrode 30, a second collecting electrode 35, and a third collecting electrode 36 are provided.

  In the fifth embodiment, five first through-hole electrodes 23 are arranged along the arrangement direction. The five first through-hole electrodes 23 are provided in two rows in the orthogonal direction. One end of each first through-hole electrode 23 is electrically connected to the first current collecting electrode 30 on the light receiving surface side of the photoelectric conversion unit 20. The other end of each first through-hole electrode 23 is electrically connected to the first wiring member 115a on the second main surface 114B side of the insulator 114.

  In the fifth embodiment, five second through-hole electrodes 25 are arranged along the arrangement direction. The five second through-hole electrodes 25 are provided in three rows in the orthogonal direction. One end of each second through-hole electrode 25 is electrically connected to the third current collecting electrode 36 on the first main surface 114 </ b> A side of the insulator 114. The other end of each second through-hole electrode 25 is electrically connected to the second wiring member 115b on the second main surface 114B side of the insulator 114.

  The first through-hole electrodes 23 and the second through-hole electrodes 25 are alternately arranged along the orthogonal direction. Here, each first through-hole electrode 23 included in one solar cell 10d and each second through-hole electrode 25 included in another solar cell 10d adjacent to one solar cell 10d are provided on a straight line. Absent. Similarly, each second through-hole electrode 25 included in one solar cell 10d and each first through-hole electrode 23 included in another solar cell 10d adjacent to one solar cell 10d are provided on a straight line. Absent.

  The third current collecting electrode 36 collects the photogenerated carriers collected from the photoelectric conversion unit 20 by the second current collecting electrode 35. In the fifth embodiment, the third current collecting electrode 36 is formed over substantially the entire length of the solar cell 10d along the arrangement direction, as shown in FIG. The third wiring member 115 c is disposed between the third current collecting electrode 36 and the end of the insulator 114 in the arrangement direction.

  The insulator 114 is disposed on the back surface of the photoelectric conversion unit 20. A third wiring member 115c is fitted into the insulator 114.

  As shown in FIGS. 21 and 22, the third wiring member 115 c is disposed at the end of the insulator 114 in the arrangement direction. The first wiring members 115a and the second wiring members 115b are disposed on the third wiring member 115c with the conductive adhesive 26 interposed therebetween.

  Here, the third wiring member 115 c is integrated with the insulator 114 by being fitted into the second main surface 114 </ b> B of the insulator 114. Therefore, as shown in FIGS. 21 and 22, the surface of the third wiring member 115 c is horizontally connected to the second main surface 114 </ b> B of the insulator 114.

(Function and effect)
The solar cell 10d according to the fifth embodiment includes a third wiring member 115c. One end of the three second wiring members 115b arranged on the back surface of one solar cell 10d is electrically connected to the third wiring member 115c included in the one solar cell 10d. One end of two first wiring members 115a disposed on the back surface of another solar cell 10d adjacent to one solar cell 10d is electrically connected to a third wiring member 115c included in the one solar cell 10d. The

  Thus, the two first wiring members 115a and the three second wiring members 115b are electrically connected by the third wiring member 115c. Therefore, even if the number of first wiring members 115a and the number of second wiring members 115b arranged on the back surface of each solar cell 10d are different, the solar cells 10d can be easily connected to each other. .

  Each solar cell 10d has a symmetric configuration in the arrangement direction and the orthogonal direction. Therefore, as described in the first embodiment, it is not necessary to rotate the solar cell 10a and the solar cell 10b halfway each other. Therefore, the manufacturing process of the solar cell string 105 can be simplified.

  Also, the two first wiring members 115a and the three second wiring members 115b are electrically connected by the third wiring member 115c. Therefore, when the solar cell string 105 is viewed from the upper surface side, each solar cell 10d seems to be connected to each other by the two first wiring members 115a extending linearly along the arrangement direction. Therefore, the appearance of the solar cell string 105 can be improved.

  Further, the third wiring member 115 c is disposed on the insulator 114. Therefore, the insulator 114 can absorb the expansion force or contraction force of the third wiring member 115c according to the temperature change. As a result, it is possible to prevent the solar cell 10d from being warped or cracked.

Further, the third wiring member 115c is fitted into the insulator 114. Therefore, the first wiring member 115a and the second wiring member 115b can be arranged without being deformed.
[Sixth Embodiment]
The sixth embodiment will be described below with reference to the drawings. In the sixth embodiment, grooves extending in the arrangement direction are formed in the insulator. In the following description, description of the same or similar parts as those in the fifth embodiment is omitted.

(Configuration of solar cell string)
FIG. 23 is a rear view of the solar cell string 106 according to the sixth embodiment. The solar cell string 106 according to the sixth embodiment has the same configuration as the solar cell string 105 according to the fifth embodiment.

(Configuration of solar cell)
FIG. 24 is a rear view of the solar cell 10e according to the sixth embodiment. FIG. 25A is a rear view of the insulator 114 included in the solar cell 10e. FIG. 25B is a top view of the insulator 114 included in the solar cell 10e. 26 is an enlarged cross-sectional view taken along the line II of FIG.

  As shown in FIG. 24, in the sixth embodiment, the second through-hole electrode 25b is provided along the arrangement direction. Specifically, the second through-hole electrode 25b is provided inside an insulator groove 114C formed in the insulator 114 described later.

  As shown in FIGS. 25A and 25B, the insulator 114 according to the sixth embodiment has a first main surface 114A, a second main surface 114B, and three insulator grooves 114C. 114 A of 1st main surfaces oppose the back surface of the photoelectric conversion part 20. FIG. The second main surface 114B is provided on the opposite side of the first main surface 114A. Each insulator groove 114C is provided substantially in parallel along the arrangement direction. Each insulator groove 114C penetrates the insulator 114 from the first main surface 114A to the second main surface 114B.

  Here, as shown in FIG. 26, the second through-hole electrode 25b is provided in the insulator groove 114C. The second through-hole electrode 25b is provided on the third current collecting electrode 36 along the arrangement direction.

(Function and effect)
In the sixth embodiment, the insulator 114 has an insulator groove 114C formed along the arrangement direction. The second through-hole electrode 25b is provided inside the insulator groove 114C. The second through-hole electrode 25b is provided on the third current collecting electrode 36 along the arrangement direction.

As described above, the second through-hole electrode 25 b is provided along the third current collecting electrode 36. Therefore, as described in the fifth embodiment, compared to the case where the plurality of second through-hole electrodes 25 are connected to the third current collecting electrode 36, the second wiring member 115b and the third current collecting electrode 36 are different from each other. The electrical resistance between them can be reduced.
[Seventh Embodiment]
The seventh embodiment will be described below with reference to the drawings. In the seventh embodiment, the third current collecting electrode is provided along the orthogonal direction. In the following description, description of the same or similar parts as those in the fifth embodiment is omitted.

(Configuration of solar cell string)
FIG. 27 is a rear view of the solar cell string 107 according to the seventh embodiment. FIG. 28 is a top view of the solar cell string 107 according to the seventh embodiment.

  As shown in FIGS. 27 and 28, the solar cell string 107 includes a plurality of solar cells 10f, a first wiring member 115a, and a second wiring member 115b. Each solar cell 10f is arranged along the arrangement direction. Each solar cell 10 f includes an insulator 114 and a third wiring member 115 c disposed on the insulator 114.

  The first wiring member 115a and the second wiring member 115b are disposed on the back surface of the solar cell 10f. Specifically, the first wiring member 115a and the second wiring member 115b are disposed on the second main surface 114B of the insulator 114 included in the solar cell 10f. A conductive adhesive 26 is provided between each of the first wiring member 115a and the second wiring member 115b and the second main surface 114B of the insulator 114 (see FIGS. 30 to 32).

  The first wiring member 115a and the second wiring member 115b are disposed along the arrangement direction on the back surface of the solar cell 10f. In the seventh embodiment, seven first wiring members 115a and six second wiring members 115b are alternately arranged along the orthogonal direction. The seven first wiring members 115a arranged on the back surface of the solar cell 10f extend toward the outside of the solar cell 10f.

  Here, as shown in FIG. 27, one end of each second wiring member 115b disposed on the back surface of one solar cell 10f is electrically connected to a third wiring member 115c included in one solar cell 10f. The One end of each first wiring member 115a disposed on the back surface of another solar cell 10f adjacent to one solar cell 10f is electrically connected to a third wiring member 115c included in the one solar cell 10f. Thereby, one solar cell 10f and another solar cell 10f are electrically connected in series.

  Therefore, as shown in FIG. 28, when the solar cell string 107 is viewed from the upper surface side, each solar cell 10f is connected to each other by seven first wiring members 115a extending linearly along the arrangement direction. looks like. Thus, the solar cell string 107 according to the seventh embodiment has a more symmetrical configuration than the solar cell string 101 according to the first embodiment.

(Configuration of solar cell)
FIG. 29 is a rear view of the solar cell 10f. FIG. 30 is an enlarged cross-sectional view taken along line JJ in FIG. 31 is an enlarged cross-sectional view taken along line KK in FIG. 32 is an enlarged cross-sectional view taken along line LL in FIG.

  As shown in FIGS. 29 to 32, the solar cell 10f includes an insulator 114, a third wiring member 115c, a photoelectric conversion unit 20, a first through-hole electrode 23, an insulating layer 24, a second through-hole electrode 25, and a first collector. A current electrode 30, a second current collecting electrode 35, and a third current collecting electrode 36 are provided.

  In the seventh embodiment, the two first through-hole electrodes 23 are arranged along the arrangement direction. Two first through-hole electrodes 23 are provided in seven rows in the orthogonal direction. One end of each first through-hole electrode 23 is electrically connected to the first current collecting electrode 30 on the light receiving surface side of the photoelectric conversion unit 20. The other end of each first through-hole electrode 23 is electrically connected to the first wiring member 115a on the second main surface 114B side of the insulator 114.

  In the seventh embodiment, two second through-hole electrodes 25 are arranged along the arrangement direction. Two rows of two second through-hole electrodes 25 are provided in the orthogonal direction. One end of each second through-hole electrode 25 is electrically connected to the third current collecting electrode 36 on the first main surface 114 </ b> A side of the insulator 114. The other end of each second through-hole electrode 25 is electrically connected to the second wiring member 115b on the second main surface 114B side of the insulator 114.

  The third current collecting electrode 36 collects the photogenerated carriers collected from the photoelectric conversion unit 20 by the second current collecting electrode 35. In the seventh embodiment, as shown in FIG. 29, the third current collecting electrode 36 is formed over substantially the entire length of the solar cell 10f along the orthogonal direction. Each second through-hole electrode 25 is provided on the third current collecting electrode 36.

  The insulator 114 is disposed on the back surface of the photoelectric conversion unit 20. A third wiring member 115c is fitted into the insulator 114.

  Specifically, as shown in FIG. 32, the third wiring member 115 c includes an end portion of the insulator 114 in the arrangement direction and seven first through-hole electrodes 23 arranged on the end side of the insulator 114 in the arrangement direction. Between. In the seventh embodiment, the third wiring member 115c is provided in the middle between the end of the insulator 114 in the arrangement direction and the seven first through-hole electrodes 23. It may be provided.

  The third wiring member 115c is integrated with the insulator 114 by being fitted into the second main surface 114B of the insulator 114.

(Function and effect)
The solar cell 10f according to the seventh embodiment includes an insulator 114, a third wiring member 115c, a first through-hole electrode 23, a second through-hole electrode 25, and a third current collecting electrode 36. The second through-hole electrode is electrically connected to the third current collecting electrode. The third current collecting electrode 36 is provided along the orthogonal direction.

  Accordingly, the third wiring member 115 c can be disposed between the end of the insulator 114 in the arrangement direction and the first through-hole electrode 23 regardless of the position where the third current collecting electrode 36 is provided. Therefore, as described in the fifth embodiment, the degree of freedom of the arrangement position of the third wiring member 115c can be improved as compared with the case where the third current collecting electrode 36 is formed along the arrangement direction. That is, the third wiring member 115 c can be disposed at any position between the end of the insulator 114 in the arrangement direction and the first through-hole electrode 23.

(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 to fourth embodiments, one insulator 14 is assigned to a plurality of solar cells 10, but the number of solar cells 10 assigned to one insulator 14 is not limited. Accordingly, one solar cell 10 may be assigned to one insulator 14.

  Although not particularly mentioned in the first to fourth embodiments, the solar cell 10 may further include a third current collecting electrode that collects photogenerated carriers from the second current collecting electrode.

  Although not specifically mentioned in the fourth embodiment, a large number of p-type regions and a large number of n-type regions may be finely formed in the arrangement direction. The present invention can also be applied to such a back junction solar cell 10.

  In the first to third and fifth to seventh embodiments, the solar cell 10 includes the first collector electrode 30 and the second collector electrode 35. However, the solar cell 10 includes the collector electrode. It does not have to be. In this case, the transparent conductive films 20c and 20e described as a part of the photoelectric conversion unit 20 function as a collecting electrode.

  Moreover, in the said 1st-3rd, 5th-7th embodiment, although the 2nd current collection electrode 35 was formed in the thin wire | line shape, the shape of the 2nd current collection electrode 35 is not limited to this.

  Further, although not particularly mentioned in the fifth to seventh embodiments, the third wiring member 115 c may be disposed between the two solar cells 10. In addition, the third wiring member 115 c may not be disposed on the insulator 114 and may be disposed on the photoelectric conversion unit 20. Note that the present invention does not limit the shape of the third wiring member 115c.

  Further, the present invention does not limit the number of wiring materials. Similarly, the present invention does not limit the number of first through-hole electrodes 23 and second through-hole electrodes 25.

  As described above, the present invention naturally includes various embodiments not described herein. Accordingly, 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.

  DESCRIPTION OF SYMBOLS 1, 2 ... Solar cell module, 10 ... Solar cell, 11 ... Light-receiving surface side protective material, 12 ... Back surface side protective material, 13 ... Sealing material, 14 ... Insulator, 14A ... 1st main surface, 14B ... 2nd Main surface, 15 ... wiring material, 15a ... conductor, 16 ... wiring material, 20 ... photoelectric conversion part, 20a ... semiconductor substrate, 20b ... first semiconductor layer, 20c ... transparent conductive film, 20d ... second semiconductor layer, 20e ... Transparent conductive film, 23 ... First through-hole electrode, 23a ... First insulator side conductive part, 23b ... Photoelectric conversion part side conductive part, 24 ... Insulating layer, 25 ... Second through-hole electrode, 25a ... Second insulator side Conductive portion, 25b ... second through-hole electrode, 26 ... conductive adhesive, 27a ... first insulator through-hole, 27b ... second insulator through-hole, 28 ... anisotropic conductive adhesive, 30 ... first collection Electrode, 34 ... insulator, 35 ... second collector electrode, 36 ... third collector 40 ... Photoelectric conversion part, 40a ... Semiconductor substrate, 40b ... First semiconductor region, 40c ... Second semiconductor region, 41 ... First collector electrode, 42 ... Second collector electrode, 43 ... First through-hole electrode, 44 ... 1st insulating layer, 45 ... 2nd through-hole electrode, 46 ... 2nd insulating layer, 101-107 ... Solar cell string, 114 ... Insulator, 114A ... 1st main surface, 114B ... 2nd main surface, 114C ... Insulator groove, 115a ... first wiring material, 115b ... second wiring material, 115c ... third wiring material

Claims (6)

A solar cell module that performs electrical connection of a plurality of solar cells on the back side of an insulator disposed on the back side of the solar cell,
The solar cell has first and second photoelectric conversion unit side conductive connection portions on the back surface,
The insulator has first and second insulator-side conductive connection portions on a first main surface,
By bonding the first main surface of the insulator to the back surface of the solar cell with an anisotropic conductive adhesive, the first insulator-side conductive connection portion is electrically connected to the first photoelectric conversion portion-side conductive connection portion. The second insulator-side conductive connection portion is electrically connected to the second photoelectric conversion portion-side conductive connection portion, and
The first and second insulator-side conductive connection portions of the insulator are electrically connected to wiring provided on a second main surface facing the first main surface of the insulator through a through hole provided in the insulator. Connected to the solar cell module.   The solar cell according to claim 1, wherein the solar cell has a p-type region and an n-type region on the back surface. The solar cell has a light receiving surface side collector electrode on the light receiving surface,
The light receiving surface side collector electrode is electrically connected to one of the first and second photoelectric conversion unit side conductive connection portions through a through hole provided through the solar cell. The solar cell of Claim 1 connected to.   The solar cell module according to any one of claims 1 to 3, wherein the insulator is integrally formed so as to straddle two or more solar cells.   The solar cell module according to any one of claims 1 to 4, wherein the insulator is made of a resin material containing a plurality of particles.   The solar cell module according to any one of claims 1 to 5, wherein the insulator is subjected to surface processing for scattering light.

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