JP5057805B2 - Solar cell array, solar cell module, and method for manufacturing solar cell array - Google Patents

Description

  The present invention relates to a solar cell array, a solar cell module, and a method for manufacturing a solar cell array. In particular, the interconnector has a stress relief portion, but reduces the difficulty in handling solar cells when manufacturing a solar cell array. The present invention relates to a solar cell array capable of reducing the distance between solar cells constituting the solar cell array, a solar cell module including the solar cell array, and a method for manufacturing the solar cell array.

  FIG. 7 shows a schematic cross-sectional view of a conventional solar cell used in the solar cell array, and FIG. 8 shows a schematic plan view of the conventional solar cell shown in FIG. As shown in FIGS. 7 and 8, the conventional solar cell includes a photoelectric conversion unit 51, an n-side electrode 52 formed on the first surface of the photoelectric conversion unit 51, and a second of the photoelectric conversion unit 51. The p-side electrode 54 formed on the surface, the metal thin film 53 formed on the third surface serving as the back surface of the photoelectric conversion unit 51, and the surfaces of the n-side electrode 52 and the p-side electrode 54 are electrically connected respectively. The photoelectric conversion part 51 is sealed with a flexible resin film 57 with an adhesive 56.

  Here, the photoelectric conversion unit 51 is formed by forming a semiconductor single crystal layer having one or more pn junctions on a semiconductor substrate to a thickness of 50 μm or less by epitaxial growth, and then peeling the semiconductor substrate from the semiconductor single crystal layer. Has been.

  The metal thin film 53 is formed to support the photoelectric conversion unit 51, and the metal thin film 53 is formed to a thickness of 100 μm or less. A pn junction is not formed between the metal thin film 53 and the p-side electrode 54.

  The interconnector 55 is a member for electrically connecting a plurality of the solar cells in series or in parallel, and is electrically connected to each of the n-side electrode 52 and the p-side electrode 54. And when connecting solar cells electrically and producing a solar cell array, the interconnector 55 electrically connected to the n side electrode 52 of the 1st solar cell, and p of a 2nd solar cell It is necessary to connect an interconnector 55 that is electrically connected to the side electrode 54.

  The interconnector 55 used in the conventional solar cell has a flat plate shape, and is made of pure silver or a silver-based material that is increased in strength by adding a small amount of additives to pure silver. Moreover, the thickness of the interconnector 55 is generally 10 μm or more and 50 μm or less.

  The conventional solar cell having the above-described configuration has a feature that the photoelectric conversion part 51 is extremely thin with a thickness of 50 μm or less and is highly flexible, so that the solar cell itself is difficult to break.

  However, when a solar cell array is manufactured by electrically connecting a plurality of solar cells in series or in parallel with the interconnector 55, the interconnector is used for the purpose of alleviating stress generated between the solar cells due to this connection. 55 needs to have a stress relief part (see, for example, Patent Document 1).

This is because when the interconnector 55 having no stress relief part is used, the solar cell and the interconnector 55 are destroyed due to the difference between the thermal contraction of the interconnector 55 and the thermal contraction of the photoelectric conversion part 51. Because there is.
JP-A-6-196744

  However, when the interconnector 55 having the conventional stress relief portion 55a as shown in the schematic plan view of FIG. 9 is used, the interconnector 55 is electrically connected for flexibility of the interconnector 55. When the subsequent solar cell is handled at the time of manufacturing the solar cell array, there is a problem that the shape of the interconnector 55 is changed and the handling is difficult.

  For example, as shown in the schematic plan view of FIG. 10, a solar cell array is obtained by electrically connecting a plurality of solar cells using an interconnector 55 having a conventional stress relief portion 55a as shown in FIG. When manufactured, there also existed a problem that the space | interval of the solar cells which comprise a solar cell array will increase.

  Accordingly, an object of the present invention is to reduce the difficulty of handling solar cells during the production of a solar cell array while the interconnector has a stress relief portion. An object of the present invention is to provide a solar cell array capable of narrowing the interval, a solar cell module including the solar cell array, and a method for manufacturing the solar cell array.

The present invention includes a first solar cell and a second solar cell, and the first solar cell and the second solar cell are respectively on the photoelectric conversion unit and the first surface of the photoelectric conversion unit. The first electrode formed, the second electrode formed on the second surface of the photoelectric conversion unit, the first interconnector connected to the surface of the first electrode, and the second electrode A photoelectric conversion unit is a semiconductor crystal layer of 50 μm or less having one or more pn junctions formed by epitaxial growth , the first interconnect and the second interconnector connected to the surface The surface is a surface oriented in the same direction as the light receiving surface of each of the first solar cell and the second solar cell. The photoelectric conversion unit, the first electrode, the second electrode, and the first interconnector And a part of the second interconnector Sealed by Chakuzai, at least a portion of the second interconnector are bent in three dimensions, and the first interconnector second interconnector and the second solar cell of the first solar cell Ri Na is connected, the first interconnector is a plate-like, the tip of the second interconnector bent portion of the facing respective light-receiving surface side of the first solar cell and the second solar cell It is not a solar cell array.

Here, in the solar cell array of the present invention, the bent portion of the second interconnector has an arc shape, and the center angle of the arc is preferably larger than 180 ° . In the solar cell array of the present invention, the bending direction of the second interconnector is a direction parallel to the light receiving surfaces of the first solar cell and the second solar cell, and the second interconnector is bent. It is preferable that the formed part and the first interconnector are connected, and the first interconnector and the second interconnector are formed in an S shape as a whole.

  In the solar cell array of the present invention, the first electrode and the second electrode of the first solar cell are installed at positions that do not face each other, and the first electrode and the second electrode of the second solar cell are arranged. The two electrodes are preferably installed at positions that do not face each other.

  In the solar cell array of the present invention, the first solar cell has a plurality of second electrodes, and a second interconnector is provided on each surface of the plurality of second electrodes of the first solar cell. Are connected one by one, the second solar cell has a plurality of first electrodes, and the first interconnector is 1 on each surface of the plurality of first electrodes of the second solar cell. It is preferable that they are connected one by one.

Moreover, this invention is a solar cell module containing one of said solar cell arrays.
The present invention is also a method for producing any one of the above solar cell arrays, wherein at least a part of the second interconnector of the first solar cell is three-dimensionally bent and then the second solar cell is manufactured. It is a manufacturing method of a solar cell array including the process of connecting the 1st interconnector to the 2nd interconnector of the 1st solar cell.

  Furthermore, the present invention provides a method for manufacturing any one of the solar cell arrays described above, wherein the second solar cell is folded before three-dimensionally bending at least a part of the second interconnector of the first solar cell. It is a manufacturing method of a solar cell array including the process of connecting the 1st interconnector to the 2nd interconnector of the 1st solar cell.

  According to the present invention, a solar cell array that can reduce the difficulty of handling while having a stress relief function, and can also reduce the interval between solar cells constituting the solar cell array, and the solar cell array And a method for producing the solar cell array.

  Embodiments of the present invention will be described below. In the drawings of the present invention, the same reference numerals represent the same or corresponding parts.

  In FIG. 1, typical sectional drawing of an example of the solar cell used for preparation of the solar cell array of this invention is shown. FIG. 2 is a schematic plan view of the solar cell array shown in FIG. As shown in FIGS. 1 and 2, the solar cell used for manufacturing the solar cell array of the present invention includes a photoelectric conversion unit 60 and a first electrode 61 formed on the first surface of the photoelectric conversion unit 60. The second electrode 62 formed on the second surface of the photoelectric conversion unit 60, the metal layer 65 formed on the third surface serving as the back surface of the photoelectric conversion unit 60, and the first electrode 61. The first interconnector 63 electrically connected to the surface of the second electrode 62 and the second interconnector 64 electrically connected to the surface of the second electrode 62, and the photoelectric conversion unit 60 includes the adhesive 56. Thus, the structure is sealed with a flexible resin film 57.

  Here, although the first interconnector 63 has a flat plate shape, the second interconnector 64 is three-dimensionally bent, and is the end of the second interconnector 64 opposite to the second electrode 62. The part is folded back to the second electrode 62 side.

  FIG. 3A shows a schematic cross-sectional view of an example of the solar cell array of the present invention. Here, the solar cell array of the present invention includes a first solar cell 80 and a second solar cell 81 having the configuration shown in FIGS. 1 and 2. The second interconnector 64 of the first solar cell 80 and the first interconnector 63 of the second solar cell 81 are electrically connected.

  FIG. 3B is a schematic enlarged view of a connection portion between the second interconnector 64 of the first solar cell 80 and the first interconnector 63 of the second solar cell 81 shown in FIG. A side view is shown.

  Here, the connecting portion shown in FIG. 3B can be formed as follows, for example. First, the flat first interconnector 63 is electrically connected to the surface of the first electrode 61 of each of the first solar cell 80 and the second solar cell 81, and the first solar cell 80 and A flat second interconnector 64 is electrically connected to the surface of each second electrode 62 of the second solar cell 81.

  Next, the end of the second interconnector 64 of each of the first solar cell 80 and the second solar cell 81 opposite to the second electrode 62 is bent toward the second electrode 62 side.

  Then, after the end portion of the second interconnector 64 is bent, the end portion of the portion of the first solar cell 80 that is folded back to the second electrode 62 side and the second solar cell. The front end portion of the first interconnector 63 of 81 is joined by welding such as parallel gap welding. As a result, an S-shape is formed by the second interconnector 64 of the first solar cell 80 after bonding and the first interconnector 63 of the second solar cell 81.

  Thus, in the solar cell array of the present invention, the second interconnector 64 of the adjacent first solar cell 80 and the first interconnector 63 of the second solar cell 81 form an S-shape. Since the S-shaped curved portion is electrically connected to the solar cell, the S-shaped curved portion serves as a stress relief portion that relieves stress between the solar cells caused by the thermal contraction difference between the interconnector and the photoelectric conversion portion of the solar cell. .

  When the first solar cell 80 and the second solar cell 81 are handled at the time of manufacturing the solar cell array of the present invention, the first interface of the first solar cell 80 and the second solar cell 81 is used. Since each of the connector 63 and the second interconnector 64 has a flat plate shape, it is more than the case of handling a solar cell to which a conventional interconnector having a stress relief portion bent in a plane as in the prior art is connected. The difficulty of handling can be reduced.

  Furthermore, in the solar cell array of the present invention, the second interconnector 64 of the first solar cell 80 is three-dimensionally folded along the connection direction between the first solar cell 80 and the second solar cell 81. Therefore, the conventional interconnector having the stress relief portion bent in a plane as in the prior art is electrically connected to the flat first interconnector 63 of the second solar cell 81. Compared with the case where it connects using, the space | interval of the 1st solar cell 80 and the 2nd solar cell 81 which comprises a solar cell array can also be narrowed.

  FIG. 4A shows a schematic cross-sectional view of another example of the solar cell array of the present invention. FIG. 4B is a schematic view of a connecting portion between the second interconnector 64 of the first solar cell 80 and the first interconnector 63 of the second solar cell 81 shown in FIG. An enlarged side view is shown.

  Here, in the solar cell array shown in FIG. 4A, the bent portion 64a of the second interconnector 64 of the first solar cell 80 has an arc shape as shown in FIG. 4B. There is a special feature. By bending in an arc shape in this way, it is possible to effectively prevent the breakage of the second interconnector 64 due to metal fatigue or the like due to thermal contraction or the like of the second interconnector 64 than when bent in an acute angle shape. It tends to be possible.

  FIG. 5A shows a schematic plan view of still another example of the solar cell array of the present invention. FIG. 5 (b) shows a schematic enlarged plan view of the solar cell constituting the solar cell array shown in FIG. 5 (a).

  Here, in the solar cell array shown in FIG. 5A, the second interconnector 64 of each of the first solar cell 80 and the second solar cell 81 is opposite to the second electrode 62 side. The end portions are three-dimensionally folded toward the second electrode 62 side, and the first interconnectors 63 of the first solar cell 80 and the second solar cell 81 are folded at a right angle in a plane. In each of the first solar cell 80 and the second solar cell 81, the first electrode 61 and the second electrode 62 are installed at positions that do not face each other.

  When the solar cell has flexibility, the thickness of the solar cell is generally reduced. Therefore, the thickness of the interconnector cannot be ignored due to the thinness of the solar cell. When the first electrode 61 and the second electrode 62 of the solar cell constituting the solar cell array face each other as shown in FIG. 2, for example, the first electrode 61 and the first interconnector 63 and in the vicinity of the connection portion between the second electrode 62 and the second interconnector 64, along the longitudinal direction of the interconnector (that is, the fold line is parallel to the longitudinal direction of the interconnector). ) When the solar cell is bent in an arc shape, the thickness of the interconnector is linearly connected along the longitudinal direction of the interconnector, so that the stress for the bending cannot be relieved, and the solar cell in the vicinity of these connecting portions There is a risk of cracking.

  Therefore, in each of the first solar cell 80 and the second solar cell 81, the first electrode 61 and the second electrode 62 do not face each other (that is, the solar cell array is configured from the position of the first electrode 61). The first interconnector 63 and the second interconnector 64 are prevented from facing each other by being installed at a position where the second electrode 62 does not exist at a position along the connection direction of the solar cell. Therefore, the generation of cracks in the solar cell can be reduced.

  FIG. 6 shows a schematic plan view of still another example of the solar cell array of the present invention. Here, in the solar cell array shown in FIG. 6, each of the first solar cell 80 and the second solar cell 81 constituting the solar cell array has a plurality of first electrodes 61 and a plurality of second electrodes 62, respectively. One second interconnector 64 is connected to each surface of the plurality of second electrodes 62 of the first solar cell 80, and the plurality of first electrodes of the second solar cell 81 are connected. A first interconnector 63 is connected to each surface of each of the electrodes 61.

  By adopting such a configuration, even if the number of interconnecting connectors increases with an increase in the area of the surfaces of the first solar cell 80 and the second solar cell 81, the stress at each connecting portion is increased. A relief part is secured. Therefore, in the case of such a configuration, even if there is a connection failure in a part of the connection part of the solar cell array, the generated current can be taken out through the other connection part. Will improve.

  Moreover, in this invention, a solar cell module is producible by sealing the solar cell array of this invention demonstrated above with conventionally well-known resin.

  Moreover, in the above, after bending the edge part of the flat 2nd interconnector 64 of the 1st solar cell 80, the surface of the 2nd interconnector 64 of the 1st solar cell 80, and the 2nd solar The case where the surface of the first interconnector 63 of the battery 81 is joined by welding or the like has been described. In the present invention, the surface of the flat second interconnector 64 of the first solar cell 80 and the second interconnector 64 are connected. After joining the surface of the flat first interconnector 63 of the solar cell 81 by welding or the like, the end of the flat second interconnector 64 of the first solar cell 80 is bent to A battery array can also be produced. In this case, in addition to the effects described above, the alignment accuracy when the second interconnector 64 of the first solar cell 80 and the first interconnector 63 of the second solar cell 81 are joined. Can be formed from the second interconnector 64 of the first solar cell 80 and the first interconnector 63 of the second solar cell 81 without damaging the S-curved portion. Can be used as a stress relief part.

  In the present invention, the photoelectric conversion unit 60 can be used without particular limitation as long as it has a function capable of converting light energy into electric energy. For example, at least one pn junction (p-type semiconductor) A stacked body of semiconductor crystal layers having a junction of a crystal layer and an n-type semiconductor crystal layer can be used.

  In the present invention, each of the first electrode 61 and the second electrode 62 can be made of a material having electrical conductivity without particular limitation. For example, the photoelectric conversion unit 60 is a laminate of semiconductor crystal layers. In the case of comprising, a metal or the like that makes ohmic contact with the semiconductor crystal layer in contact can be used.

  In the present invention, the first interconnector 63 and the second interconnector 64 can be made of a material having electrical conductivity without any particular limitation. For example, a metal containing copper or silver or the like can be used. Can be used.

  The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

  ADVANTAGE OF THE INVENTION According to this invention, the difficulty of the handling of a solar cell at the time of preparation of a solar cell array can be reduced, although the interconnector has a stress relief part, and the space | interval of the solar cells which comprise a solar cell array A solar cell array that can be narrowed, a solar cell module including the solar cell array, and a method for manufacturing the solar cell array can be provided.

It is typical sectional drawing of an example of the solar cell used for preparation of the solar cell array of this invention. FIG. 2 is a schematic plan view of the solar cell array shown in FIG. 1. (A) is typical sectional drawing of an example of the solar cell array of this invention, (b) is the 2nd interconnector of the 1st solar cell shown in (a), and the 1st of the 2nd solar cell. It is a typical expanded side view of a connection part with no interconnector. (A) is typical sectional drawing of another example of the solar cell array of this invention, (b) is the 2nd interconnector of a 1st solar cell shown to (a), and a 2nd solar cell. It is a typical expanded side view of a connection part with the 1st interconnector. (A) is a typical top view of further another example of the solar cell array of this invention, (b) is a typical enlarged plan view of the solar cell which comprises the solar cell array shown to (a). . FIG. 6 is a schematic plan view of still another example of the solar cell array of the present invention. It is typical sectional drawing of the conventional solar cell used for a solar cell array. It is a typical top view of the conventional solar cell shown by FIG. It is a typical top view of the interconnector which has the conventional stress relief part. It is a typical top view of the conventional solar cell array.

Explanation of symbols

  51, 60 Photoelectric conversion part, 52 n-side electrode, 53 metal thin film, 54 p-side electrode, 55 interconnector, 55a stress relief part, 56 adhesive, 57 resin film, 61 first electrode, 62 second electrode, 63 1st interconnector, 64 2nd interconnector, 64a Bending part, 65 Metal layer, 80 1st solar cell, 81 2nd solar cell.

Claims (8)

Including a first solar cell and a second solar cell;
Each of the first solar cell and the second solar cell includes a photoelectric conversion unit, a first electrode formed on the first surface of the photoelectric conversion unit, and a second surface of the photoelectric conversion unit. A second interconnect formed on the first electrode, a first interconnector connected to the surface of the first electrode, and a second interconnector connected to the surface of the second electrode;
Each of the first solar cell and the second solar cell has flexibility,
The first surface and the second surface are surfaces oriented in the same direction as the respective light receiving surfaces of the first solar cell and the second solar cell,
The photoelectric conversion unit, the first electrode, the second electrode, a part of the first interconnector and a part of the second interconnector are each sealed with an adhesive,
At least a portion of the second interconnector is three-dimensionally bent;
Ri Na is connected to the second interconnector of the first solar cell and the first interconnector of the second solar cell,
The first interconnector has a flat plate shape,
The solar cell array in which the front-end | tip of the bent part of the said 2nd interconnector does not face each said light-receiving surface side of a said 1st solar cell and a said 2nd solar cell. 2. The solar cell array according to claim 1 , wherein a bent portion of the second interconnector has an arc shape, and a central angle of the arc is larger than 180 ° . The bending direction of the second interconnector is a direction parallel to the light receiving surface of each of the first solar cell and the second solar cell;
The bent portion of the second interconnector is connected to the first interconnector, and the first interconnector and the second interconnector are formed in an S shape as a whole. The solar cell array according to claim 1, wherein: The first electrode and the second electrode of the first solar cell are installed at positions that do not face each other, and the first electrode and the second electrode of the second solar cell are The solar cell array according to any one of claims 1 to 3, wherein the solar cell array is installed at positions that do not face each other. The first solar cell has a plurality of the second electrodes, and one second interconnector is connected to each surface of the plurality of second electrodes of the first solar cell. And
The second solar cell includes a plurality of the first electrodes, and one first interconnector is connected to each surface of the plurality of first electrodes of the second solar cell. wherein the is, the solar cell array according to any one of claims 1 to 4. The solar cell module containing the solar cell array in any one of Claim 1 to 5 . A method of manufacturing a solar cell array according to any one of claims 1 to 5, wherein the second after folding at least a portion of said second interconnector of the first solar cell stereoscopically The manufacturing method of a solar cell array including the process of connecting the said 1st interconnector of a solar cell to the said 2nd interconnector of a said 1st solar cell. A method of manufacturing a solar cell array according to any one of claims 1 to 5, wherein the first of the second interconnector of a solar cell at least a portion of said second before sterically folding The manufacturing method of a solar cell array including the process of connecting the said 1st interconnector of a solar cell to the said 2nd interconnector of a said 1st solar cell.

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