JP2012174724A - Insulation sheet with wiring, method of manufacturing the same, insulation sheet equipped with wiring and integrated with solar cell, method of manufacturing the same, and solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an insulation sheet equipped with wiring, whereby insulation between wirings is retained when manufacturing a solar cell module, and a large-sized solar cell module can be manufactured.SOLUTION: This insulation sheet is equipped with the wiring to which a plurality of solar cell electrodes are electrically connected. The insulation sheet includes an insulating base material 1 made of a resin having adhesiveness on the surface thereof during normal temperatures and shrinking by heating to lose the adhesiveness on the surface, and a wiring 2 formed on one face side of the insulating base material 1 so that electrode connecting wirings 2a,2b formed into a pattern corresponding to the pattern of the electrodes in a plurality of unit regions U corresponding to the solar cell on one face side of the insulating base material 1 and wiring connecting parts 2c for electrically connecting the electrode connecting wirings 2a, 2b each other formed in the unit region U are integrated. The wiring 2 is bonded to the surface of the insulating base material 1 by the adhesiveness on the surface of the insulating base material 1.

Description

  The present invention relates to an insulating sheet with wiring and a manufacturing method thereof, an insulating sheet with wiring integrated with a solar battery cell and a manufacturing method thereof, a solar cell module, and a manufacturing method thereof.

  In the 21st century, the price increase of fossil energy and the global warming problem due to the increase of carbon dioxide in the atmosphere are becoming more prominent. For this reason, development of so-called natural energy is desired. Among them, the spread of solar power generation using solar cells is under development, supported by the energy policies of governments in each country.

  Conventional solar cells are mainly solar cells having double-sided electrodes in which electrodes are formed on the light-receiving surface of a substrate material such as silicon and the back surface on the opposite side. On the other hand, in recent years, a solar cell having only a back electrode in which both a p-type electrode and an n-type electrode are formed on the back surface of a substrate material (hereinafter referred to as a back electrode type solar cell) is also being put into practical use. .

  Correspondingly, a back electrode solar cell is formed on the wiring material of the insulating sheet by using an insulating sheet obtained by patterning a wiring material having electrical conductivity on the surface of the insulating base material having electrical insulation. A solar cell module for electrically connecting cell electrodes has been proposed (see, for example, Patent Document 1).

  The solar cell module described in Patent Document 1 described above is manufactured as follows. First, a metal foil such as copper or aluminum is bonded to the surface of an insulating substrate made of a polymer material or the like. Next, by etching unnecessary portions of the metal foil, a patterned wiring is formed on the insulating substrate.

  Next, the back electrode type solar cell is connected to the wiring on the insulating substrate by joining the wiring patterned on the insulating substrate and the electrode of the back electrode type solar cell using a conductive adhesive. And the back electrode type solar battery cell and the insulating base material are integrated. Then, sealing materials are respectively provided between the back electrode type solar cells integrated with the insulating base material and the transparent base material, and between the back electrode type solar cells and the sheet for protecting the back surface. A solar cell module is produced by arranging and performing a pressure-bonding process while heating.

  The back electrode type solar battery cell is formed with a predetermined gap between the p-type electrode and the n-type electrode. It is preferable that the distance between the p-type electrode and the n-type electrode is as short as possible because the current that can be taken out increases when the number of electrodes is increased as much as possible. Therefore, it is necessary to shorten the wiring interval between the p-type wiring and the n-type wiring patterned on the insulating base as much as possible.

US Pat. No. 5,951,786 JP 2010-157530 A

  However, an insulating base material mainly made of a polymer material is likely to undergo deformation such as heat shrinkage during the process of heating and pressure-bonding the sealing material. Further, the wiring material mainly made of metal foil is likely to be deformed such as elongation by the same processing.

  In recent years, there has been an increasing demand for high-power solar cell modules. In order to increase the output of the solar cell module, it is inevitable to increase the size of the insulating base material. However, the larger the area of the solar cell module, the larger the deformation due to the heat treatment as described above, and the larger the dimensional tolerance of the wiring formed on the insulating substrate. Therefore, when the insulating base is enlarged, the distance between the two wirings cannot be shortened in order to maintain the insulation between the p-type wiring and the n-type wiring patterned on the insulating base. was there.

  Moreover, in order to solve the above problems, the size of the insulating sheet on which the wiring is patterned is reduced, and the number of back electrode type solar cells installed on one insulating sheet is nine or six, It has been proposed to produce a large-sized solar cell with an insulating sheet and a solar cell module by combining a plurality of sheets (for example, see Patent Document 2).

  However, even in such a form of Patent Document 2, deformation due to heat, which is pointed out as a problem of Patent Document 1 described above, still occurs. That is, while the amount of deformation is reduced by the downsizing of the insulating sheet, the distance between the wirings is also shortened. Therefore, it cannot be concluded that the case where the insulation is not maintained does not occur.

  Moreover, in the form of patent document 2, a miniaturized insulation sheet is once produced, and this insulation sheet is further connected to produce a solar cell module. In this case, the number of man-hours is increased as compared with a case where solar cells necessary for one solar cell module are arranged at the same time on an insulating sheet provided with wiring. For this reason, the form of Patent Document 2 is disadvantageous because it imposes a heavy burden on the manufacturing process, the cost, and the manufacturing time.

  And in any case of patent document 1 and patent document 2, a conductive adhesive is mainly used for the connection of the photovoltaic cell and the wiring on an insulating sheet. For this reason, there exists a problem that the resistance value of a connection with a photovoltaic cell and the wiring on an insulating sheet is high compared with the case of the conventional solder connection, and the degree of a current loss becomes large.

  The present invention has been made in view of the above, and maintains an insulating property between wirings in the production of a solar cell module, and includes an insulating sheet with wiring provided with a wiring capable of manufacturing a large-sized solar cell module, and this insulation It aims at obtaining the solar cell module produced using the insulating sheet with a photovoltaic cell integrated wiring produced using the sheet | seat, this insulating sheet with the photovoltaic cell integrated wiring, and these manufacturing methods.

  In order to solve the above-described problems and achieve the object, the insulating sheet with wiring according to the present invention is an insulating sheet with wiring including wiring to which electrodes of a plurality of solar cells are electrically connected, Insulating base material made of a resin that has adhesiveness on the surface and loses adhesiveness on the surface when heated at room temperature, and the shape of the solar cell on one side of the insulating base material The electrode connection wiring formed in a pattern corresponding to the pattern of the electrodes in a plurality of unit regions corresponding to, and the wiring connection portion for electrically connecting the electrode connection wirings formed in the unit region And a wiring formed on one side of the insulating base material, and the wiring is adhered to the surface of the insulating base material by the adhesiveness of the surface of the insulating base material. Being And butterflies.

  According to the present invention, in the production of a solar cell module, while maintaining the insulation between the wirings, the insulation sheet with the wiring provided with the wiring capable of producing a large-sized solar cell module, and the solar battery cell produced using this insulation sheet There is an effect that an insulating sheet with integrated wiring and a solar cell module can be obtained.

1-1 is a figure which shows schematic structure of the insulating sheet with wiring concerning embodiment of this invention. 1-2 is principal part sectional drawing which shows schematic structure of the insulating sheet with wiring concerning embodiment of this invention. FIGS. 2-1 is a schematic diagram which shows an example of the pattern of the wiring in the insulating sheet with wiring concerning embodiment of this invention. FIGS. FIG. 2-2 is an enlarged view of an example of a wiring pattern in the insulating sheet with wiring according to the embodiment of the present invention, and is an enlarged view of a part of FIG. 2-1. FIGS. 3-1 is a figure which shows schematic structure of the insulating sheet with a photovoltaic cell integrated wiring concerning embodiment of this invention. 3-2 is principal part sectional drawing which shows schematic structure of the insulating sheet with a photovoltaic cell integrated wiring concerning embodiment of this invention. FIG. 4: is principal part sectional drawing which shows schematic structure of the back surface electrode type photovoltaic cell concerning embodiment of this invention. FIG. 5 is a plan view of the back surface of the semiconductor substrate of the back electrode type solar cell according to the embodiment of the present invention. FIG. 6 is a cross-sectional view showing a schematic configuration of the solar cell module according to the embodiment of the present invention. 7-1 is sectional drawing which shows the manufacturing method of the solar cell module concerning this Embodiment. 7-2 is sectional drawing which shows the manufacturing method of the solar cell module concerning this Embodiment. 7-3 is sectional drawing which shows the manufacturing method of the solar cell module concerning this Embodiment. 7-4 is sectional drawing which shows the manufacturing method of the solar cell module concerning this Embodiment.

  DESCRIPTION OF EMBODIMENTS Embodiments of an insulating sheet with wiring and a manufacturing method thereof, a solar cell integrated wiring insulating sheet and a manufacturing method thereof, a solar cell module and a manufacturing method thereof according to the present invention will be described below in detail with reference to the drawings. . In addition, this invention is not limited to the following description, In the range which does not deviate from the summary of this invention, it can change suitably. In the drawings shown below, the scale of each member may be different from the actual scale for easy understanding. The same applies between the drawings. Further, even a plan view may be hatched to make the drawing easy to see.

Embodiments Hereinafter, embodiments of the present invention will be described in the order along the manufacturing process. 1-1 is a figure which shows schematic structure of the insulating sheet 10 with wiring concerning embodiment of this invention. 1-2 is principal part sectional drawing which shows schematic structure of the insulating sheet 10 with wiring concerning embodiment of this invention. FIG. 1-2 is a main part sectional view taken along line AA ′ in FIG. 1-1.

  The insulating sheet with wiring 10 according to the present embodiment is arranged on the insulating base material 1 by integrating the insulating base material 1, the electrode connection wiring and the connection portion connecting the electrode connection wiring. Wiring 2 is provided.

  In general, the material of the insulating substrate may be a material having high electrical insulation, and typical materials include, for example, polyethylene terephthalate, polyvinyl fluoride, polyimide, and the like. However, the insulating base material 1 according to the present embodiment has not only high electrical insulating properties, but the insulating base material 1 itself as a so-called sealing material when a solar cell module is manufactured as described later. It has a role.

  Therefore, the material of the insulating base material 1 has high electrical insulation, and the insulating base material 1 itself can be used as a so-called sealing material when a solar cell module is manufactured. Here, being usable as a sealing material is made of a thermosetting material that can be deformed into a desired shape when a solar cell module is manufactured (at the time of lamination).

  Typical materials satisfying such conditions include, for example, ethylene vinyl acetate resin, polyvinyl butyral resin, epoxy resin, acrylic resin, urethane resin, olefin resin, polyester resin, silicone resin, polystyrene. Resin, polycarbonate resin, rubber resin and the like. Of these, at least one kind of material can be used as the material of the insulating substrate 1. Note that these materials have a property of being cured and contracted by heat treatment. When the insulating base material 1 is made of such a material, it is not necessary to prepare a sealing material separately when manufacturing the solar cell module.

  In addition, for example, ethylene vinyl acetate resins have various compositions. However, the composition of the material of the insulating substrate 1 is not particularly limited as long as it has desired characteristics as a sealing material. In addition, the thickness of the insulating substrate 1 is not particularly limited, and a typical thickness may be, for example, 200 μm or more and 800 μm or less.

  FIGS. 2-1 is a schematic diagram which shows an example of the pattern of the wiring 2 in the insulating sheet 10 with wiring concerning embodiment of this invention. FIG. 2-2 is an enlarged view of an example of the pattern of the wiring 2 in the insulating sheet with wiring 10 according to the embodiment of the present invention, and is a diagram in which a part of FIG. 2-1 is enlarged.

  The wiring 2 has an n-type electrode connection wiring 2 a and a p-type electrode connection wiring 2 b in the unit region U. The unit region U is a region to which one back electrode type solar cell is connected in the insulating sheet with wiring 10. In the insulating sheet with wiring 10, a plurality of unit regions U are provided in a matrix in both the vertical and horizontal directions by the number of back electrode type solar cells connected to the insulating sheet with wiring 10.

  The n-type electrode connection wiring 2a is a wiring electrically connected to the n-type electrode of the back electrode type solar battery cell, and is formed in a first comb shape. The p-type electrode connection wiring 2b is a wiring that is electrically connected to the p-type electrode of the back electrode type solar cell, and is formed in a second comb shape. The n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b are arranged so that the portions corresponding to the comb teeth are alternately engaged with each other with a predetermined interval in the comb shape. . That is, one n-type electrode connection wiring 2a corresponding to comb teeth in the first comb shape and one p-type electrode connection wiring 2b corresponding to comb teeth in the second comb shape. Are arranged so that they are alternately meshed with each other at a predetermined interval.

  In addition, the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b arranged in the adjacent unit region U are electrically connected across the unit region U by the wiring connection portion 2c. That is, the wiring connection portion 2 c includes a comb-shaped n-type electrode connection wiring 2 a formed in one unit region U among the adjacent unit regions U and a comb-shaped wiring formed in the other unit region U. The p-type electrode connection wiring 2b is electrically connected.

  The pattern of the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b is set corresponding to the electrode pattern of the back electrode type solar battery cell. Therefore, the pattern of the wiring 2 is not limited to the pattern shown in FIGS. 2-1 and 2-2, and is appropriately changed and set according to the electrode shape of the back electrode type solar battery cell.

  The material of the wiring 2 is not particularly limited as long as it is a material having electrical conductivity. Typical materials that can be used as the material of the wiring 2 include, for example, copper, silver, aluminum, and the like, and one or more of these can be used at the same time. The thickness of the wiring 2 is not particularly limited, and a typical thickness may be, for example, 50 μm or more and 300 μm or less.

  Below, the manufacturing method of the insulating sheet 10 with wiring concerning this Embodiment comprised as mentioned above is demonstrated. First, a substantially square-shaped insulating substrate 1 having a predetermined size of a substantially square shape is prepared.

  Next, the wiring 2 having a predetermined pattern is formed. The pattern of the wiring 2 can be formed by etching away unnecessary portions other than the pattern of the wiring 2 from a metal foil or the like having a uniform area according to the size of the insulating substrate 1. The wiring 2 pattern may be formed by removing unnecessary portions other than the wiring 2 pattern from a metal foil or the like by a method such as die cutting. Further, the pattern of the wiring 2 may be formed by cutting from a metal foil or the like using an energy beam such as a laser.

  Next, the wiring 2 formed in this way is bonded to the surface of the insulating substrate 1 with an adhesive. Adhesion between the wiring 2 and the insulating base material 1 is possible with the use of a slight amount of adhesive since the surface of the insulating base material 1 has adhesiveness. For example, in order not to cause displacement of the wiring 2 on the insulating base material 1, for example, the wiring connecting portion 2c and only the four corners and the center in the unit region U are bonded with an adhesive, and the other portions are insulating bases. The wiring 2 and the insulating substrate 1 are bonded to each other by the adhesiveness of the surface of the material 1. Typical adhesives used at this time include, for example, water-based adhesives and starch-based adhesives. By carrying out the above steps, the insulating sheet with wiring 10 according to the present embodiment is formed.

  Next, the insulating sheet 20 with integrated wiring of the solar battery cell configured using the insulating sheet with wiring 10 according to the present embodiment will be described. FIG. 3-1 is a diagram illustrating a schematic configuration of an insulating sheet 20 with a photovoltaic cell integrated wiring according to an embodiment of the present invention. 3-2 is principal part sectional drawing which shows schematic structure of the insulating sheet 20 with a photovoltaic cell integrated wiring concerning embodiment of this invention. FIG. 3B is a cross-sectional view of the main part along the line B-B ′ in FIG. 3A.

  Insulating sheet 20 with a photovoltaic cell integrated wiring according to the present embodiment is obtained by bonding back electrode type photovoltaic cell 30 onto insulating sheet 10 with wiring. That is, the insulating sheet 20 with integrated wiring of the solar battery cell is configured by joining the electrode of the back electrode type solar battery cell 30 onto the wiring 2 of the insulating sheet 10 with wiring using a metal paste.

  FIG. 4 is a cross-sectional view of an essential part showing a schematic configuration of the back electrode type solar battery cell 30 according to the present embodiment. The back electrode type solar battery cell 30 shown in FIG. 4 includes a semiconductor substrate 31, an antireflection film 32, and a passivation film 33. The semiconductor substrate 31 is a semiconductor substrate such as a silicon substrate having n-type or p-type conductivity, for example. As the semiconductor substrate 31, for example, a silicon substrate made of polycrystalline silicon or single crystal silicon having n-type or p-type conductivity can be used.

  The antireflection film 32 is formed on the uneven surface of the semiconductor substrate 31 that becomes the light receiving surface of the back electrode type solar battery cell 30. As the antireflection film 32, for example, a silicon nitride (SiN) film or the like can be used.

The passivation film 33 is formed on the back surface of the semiconductor substrate 31 that is the back surface of the back electrode type solar battery cell 30. As the passivation film 33, for example, a silicon oxide (SiO ₂ ) film, a silicon nitride (SiN) film, or a stacked body of a silicon oxide (SiO ₂ ) film and a silicon nitride (SiN) film can be used.

  An n-type impurity diffusion region 34 formed by diffusing an n-type impurity such as phosphorus and a p-type impurity diffusion region 35 formed by diffusing a p-type impurity such as boron are formed on the back surface of the semiconductor substrate 31. Are alternately formed at predetermined intervals. Further, the passivation film 33 on the back surface of the semiconductor substrate 31 is provided with a contact hole at a position corresponding to the n-type impurity diffusion region 34 and the p-type impurity diffusion region 35. An n-type electrode 36 that is electrically connected to the n-type impurity diffusion region 34 through a contact hole and a p-type electrode 37 that is electrically connected to the p-type impurity diffusion region 35 are respectively provided on the back surface of the semiconductor substrate 31. ing. As the n-type electrode 36 and the p-type electrode 37, for example, electrodes made of a metal such as silver can be used.

  Regardless of whether the semiconductor substrate 31 has an n-type or p-type conductivity type, the n-type impurity diffusion region 34 and the p-type impurity diffusion region 35 are each joined to the semiconductor substrate 31. Therefore, on the back side of the semiconductor substrate 31 having n-type or p-type conductivity, a plurality of pn junctions are formed at the interface between the n-type impurity diffusion region 34 or the p-type impurity diffusion region 35 and the semiconductor substrate 31. Regardless of the conductivity type of the semiconductor substrate 31, a pn junction may be formed by contact between the adjacent n-type impurity diffusion region 34 and the p-type impurity diffusion region 35.

  FIG. 5 is a plan view of the back surface of the semiconductor substrate 31 of the back electrode type solar cell 30. As shown in FIG. 5, the pattern of the n-type electrode 36 and the p-type electrode 37 corresponds to the pattern of the wiring 2 of the insulating sheet with wiring 10. That is, the n-type electrode 36 and the p-type electrode 37 are each formed in a comb shape. Then, the portions corresponding to the comb teeth of the comb-shaped n-type electrode 36 and the portions corresponding to the comb teeth of the comb-shaped p-type electrode 37 are alternately meshed with each other at a predetermined interval. An n-type electrode 36 and a p-type electrode 37 are arranged.

  In addition, each shape and arrangement | positioning of the electrode 36 for n-types and the electrode 37 for p-types of the back surface of the back electrode type photovoltaic cell 30 are not limited to the structure shown by FIG. 5, The wiring 2 of the insulating sheet 10 with wiring Any shape and arrangement that can be electrically connected to each pattern may be used. For example, the n-type electrode 36 and the p-type electrode 37 may be formed as dot-like electrodes arranged in a line at predetermined intervals, respectively.

  Below, the manufacturing method of the insulating sheet 20 with a photovoltaic cell integrated wiring concerning this Embodiment comprised as mentioned above is demonstrated. First, the back electrode type solar cell 30 is produced by a known method. Moreover, the insulating sheet 10 with wiring is produced by the method described above.

  Next, the wiring-attached insulating sheet 10 is arranged with the wiring 2 facing upward, and a metal paste for connecting the back electrode type solar cell 30 is applied onto the wiring 2. The paste application method may be performed by a printing method such as screen printing, or may be performed by a direct drawing method using an injection nozzle or the like. Moreover, since the pattern of the wiring 2 has the same shape as the electrode pattern of the back electrode type solar battery cell 30, a metal paste can be obtained by embossing a mold molded in the same manner as the electrode pattern of the back electrode type solar battery cell 30. May be applied by stamping.

  The metal paste used here is a low-temperature sintered type in which the connection is formed at a relatively low temperature, and the heat treatment temperature is 200 ° C. or lower, preferably 100 ° C. to 150 ° C. for connection. The treatment is completed within about 10 minutes. By using a metal paste that can be connected by heating at a low temperature of 200 ° C. or lower, the insulating base material 1 can substantially retain its shape, and can function as an original base material even after heating. . Further, heating at less than 100 ° C. is not preferable because the adhesiveness between the wiring 2 and the back electrode type solar battery cell 30 is insufficient and electrical bonding is also insufficient.

  Typical conductive materials used for the metal paste include silver, copper, gold, platinum, palladium, and the like. One or more kinds of metal pastes can be used at the same time. The metal paste may be applied to the n-type electrode 36 and the p-type electrode 37 of the back electrode type solar battery cell 30.

  Next, the back electrode type solar battery cell 30 is aligned with the unit region U in a state where the back surface of the back electrode type solar battery cell 30 is opposed to the wiring 2 coated with the metal paste, and on the insulating sheet with wiring 10. Is placed on the back electrode type solar battery cell 30. Here, in the alignment of the back electrode type solar cell 30, the pattern of the n-type electrode 36 and the p-type electrode 37 is matched with the wiring 2 of the insulating sheet 10 with wiring. That is, a portion corresponding to the comb teeth of the comb-shaped n-type electrode 36 in the back electrode type solar cell 30 and a portion corresponding to the comb teeth of the comb-shaped n-type electrode connection wiring 2a of the insulating sheet 10 with wiring. And are superimposed. Further, a portion corresponding to the comb teeth of the comb-shaped p-type electrode 37 in the back electrode type solar cell 30 and a portion corresponding to the comb teeth of the comb-shaped p-type electrode connecting wiring 2b of the insulating sheet 10 with wiring. And are superimposed.

  In a state where the back electrode type solar cell 30 is placed on the insulating sheet 10 with wiring, heat treatment is performed at a temperature and heating time suitable for the metal paste. By this heat treatment, the n-type electrode 36 and the p-type electrode 37 of the back electrode type solar battery cell 30 and the wiring 2 of the insulating sheet 10 with wiring are electrically connected via a metal paste, so that the back electrode type solar cell is obtained. The battery cell 30 and the insulating sheet 10 with wiring are joined.

  Here, regarding the joining of the insulating sheet with wiring 10 and the back electrode type solar battery cell 30 according to the present embodiment, as described above, the four corners and the center in the unit region U of the wiring 2, and the wiring connection portion 2c. Are largely adhered to each other by an adhesive and largely depends on the tackiness of the surface of the insulating substrate 1.

  When the heat treatment as described above is performed, the wiring 2 forms a strong structure integrated with the back electrode solar cell 30 due to the adhesiveness of the metal paste. On the other hand, the insulating substrate 1 has a property of being cured and contracted by heat treatment. For this reason, the adhesiveness of the surface of the insulating base material 1 is lost by the heat treatment, and the adhesion between the wiring 2 and the insulating base material 1 is lost due to the difference in contraction (extension) rate. That is, during the heat treatment, an integrated structure joined to the wiring 2 and the back electrode solar cell 30 is formed, but the structure is not joined to the insulating substrate 1.

  And the insulating base material 1 which lost adhesiveness heat-shrinks the insulating base material 1 when heat processing is complete | finished, and a temperature falls, and the adhesiveness of the surface revives. Thereby, the structure is bonded again due to the adhesiveness of the surface of the insulating base material 1 and the insulating base material 1 that has returned to a predetermined size by the heat shrinkage after the heat treatment. Here, within the above-described processing conditions, the shape of the insulating base material 1 does not change greatly, and the initial shape of the insulating base material 1 is substantially retained.

  Thereby, the optimal design regarding the dimension of the wiring 2 can be performed, without worrying about the dimensional tolerance by the deformation | transformation of the insulating base material 1 by heat processing. That is, even when the insulating substrate 1 is enlarged to produce a large solar cell module, the dimensional tolerance between the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b is increased. In addition, sufficient insulation can be maintained between the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b.

  Further, most of the adhesion between the back electrode type solar cell 30 and the wiring 2 is performed by the adhesiveness of the surface of the insulating base material 1, and only a part thereof uses an aqueous adhesive or a starch-based adhesive. Are attached. For this reason, the resistance value of the connection does not increase as in the case where a conductive adhesive or the like is used for the connection between the back electrode type solar cell 30 and the wiring 2, and the current loss does not increase.

  Through the above steps, a predetermined number of back electrode type solar cells 30 are joined in a matrix to the insulating sheet 10 with wiring, thereby achieving the embodiment of the present invention shown in FIGS. 3-1 and 3-2. Such an insulation sheet 20 with solar cell integrated wiring is produced.

  In addition, although the solar cell integrated wiring insulating sheet 20 according to the present embodiment has been described in the embodiment on the assumption that it is used for a solar cell module described later, it is used for a general solar cell module. Such a large number of solar cells is not necessarily limited. That is, there is no restriction on the number of solar cells used, and there is no restriction on the size of the solar cells themselves. Therefore, in the insulating sheet 20 with the photovoltaic cell integrated wiring according to the present embodiment, it can be applied as an auxiliary power source for a portable device such as a mobile phone by producing the smaller sheet.

  Below, the solar cell module 40 comprised using the insulating sheet 20 with a photovoltaic cell integrated wiring concerning this Embodiment is demonstrated. FIG. 6 is a cross-sectional view showing a schematic configuration of the solar cell module 40 according to the embodiment of the present invention. The solar cell module 40 according to the embodiment of the present invention includes an insulating sheet 20 with wiring integrated with solar cells in a transparent resin 43 that is a sealing material sandwiched between a transparent substrate 41 and a back sheet 42. Is sealed.

  The transparent substrate 41 is a light-receiving surface side protection member that is disposed on the light-receiving surface side and protects the insulating sheet 20 with the photovoltaic cell integrated wiring. The transparent substrate 41 is not particularly limited as long as it is a transparent substrate that is transparent to sunlight. As a typical material that can be used as the transparent substrate 41, for example, a glass substrate or the like can be cited.

  The back surface sheet 42 is a back surface side protection member which is arrange | positioned on the opposite side to a light-receiving surface, and protects the insulating sheet 20 with a photovoltaic cell integrated wiring. The material of the back sheet 42 is not particularly limited as long as it has sufficient strength, moisture resistance, and weather resistance to protect the solar cell module. Typical materials that can be used as the back sheet 42 include polyester, polyvinyl, polycarbonate, and polyimide materials. One or a plurality of types of the back sheet 42 can be used at the same time.

  Next, a method for manufacturing the solar cell module 40 according to the present embodiment configured as described above will be described with reference to FIGS. First, the insulating sheet 20 with a photovoltaic cell integrated wiring is produced by the method described above. 7A to 7D are cross-sectional views illustrating a method for manufacturing the solar cell module 40 according to the present embodiment.

  Next, the transparent substrate 41 is installed, and the transparent resin 44 is installed on the transparent substrate 41 (FIG. 7-1). The material of the transparent resin 44 used here is not particularly limited as long as it is a transparent resin having translucency with respect to sunlight. Typical examples of the transparent substrate 41 that can be used include ethylene vinyl acetate resin, polyvinyl butyral resin, epoxy resin, acrylic resin, urethane resin, olefin resin, polyester resin, and silicone. Resin, polystyrene resin, polycarbonate resin, rubber resin and the like. As the transparent resin 44, one or more kinds of them can be used at the same time. Moreover, the transparent resin 44 may be the same type as the insulating base material 1 of the insulating sheet with wiring 10 or may be a different type. Here, since the insulating base material 1 also functions as a sealing material, it is not necessary to separately prepare a sealing material between the insulating sheet 20 with the solar cell integrated wiring and the back sheet 42.

  Next, the insulating sheet 20 with solar cell integrated wiring is placed on the transparent resin 44 so that the insulating base material 1 is on the top (FIG. 7-2), and the back sheet 42 is further placed thereon (see FIG. 7-2). Fig. 7-3). And by heat-processing in the state which these were crimped | bonded, the insulation sheet 20 with a photovoltaic cell integrated wiring is sealed in the transparent resin 43 formed by integrating the transparent resin 44 and the insulating base material 1. The solar cell module 40 is produced (FIG. 7-4).

  It is preferable to use a vacuum heating / crimping device called a laminator, for example, for the heating and pressure-bonding treatment in producing the solar cell module. By using the laminator, the transparent resin 44 and the insulating base material 1 are heated and deformed, and these are integrated by thermosetting, and the solar cell integrated wiring-insulated sheet 20 is sealed in the transparent resin 43. be able to.

  In vacuum heating and pressure bonding, literally, heating and pressure bonding are performed at a pressure lower than atmospheric pressure, and by using this, between the transparent substrate 41 and the transparent resin 44, between the transparent resin 44 and the insulating sheet 20 with wiring integrated with solar cells. In addition, air gaps and bubbles are less likely to remain between the insulating sheet 20 with solar cell integrated wiring and the back sheet 42, and each is pressure-bonded with a uniform pressure. The conditions for the vacuum heating / compression treatment depend on the transparent resin 44 used and the material of the insulating substrate 1, but the typical temperature is 200 ° C. or less, preferably 150 ° C. to 200 ° C. .

  Therefore, when the solar cell module 40 is manufactured, first, the insulating sheet with wiring 10 according to the present embodiment and the back electrode type solar cell 30 are joined in a range of 100 ° C. to 150 ° C. The insulating sheet 20 with cell-integrated wiring is prepared, and the transparent substrate 41, the transparent resin 44, the insulating sheet 20 with integrated wiring of the solar battery cell, and the back sheet 42 are vacuum-heated and pressure-bonded in the range of 150 ° C to 200 ° C.

  Through the above steps, the solar cell module 40 according to the embodiment of the present invention shown in FIG. 6 is produced.

  Further, the back sheet 42 is not only a resin material but also a composite material in which a metal foil material is bonded, or a light reflection effect, in order to improve the strength, moisture resistance and weather resistance sufficient to protect the solar cell module 40. It is also possible to use a metal having a large refractive index or a material having a large refractive index attached by vapor deposition or the like.

  Moreover, in the solar cell module 40, in order to improve the adhesiveness of the laminated end surface and prevent intrusion of moisture or the like from the outside, the end surface can be protected with a rubber-based resin tape or the like. A typical material of the rubber-based resin is butyl rubber or the like.

  Moreover, in order to handle easily as a structure, the outer periphery of the solar cell module 40 can also be enclosed with a metal frame. A typical material for the metal frame is aluminum (alloy) or the like.

  As described above, in the present embodiment, the insulating substrate 1, which is an insulating substrate that can be used as a sealing material when the solar cell module 40 is manufactured, the n-type electrode connection wiring 2a, and the p-type electrode By connecting the wiring 2b for connection and the wiring connection portion 2c and bonding the wiring 2 arranged on the insulating base material 1, the insulating sheet 10 with wiring is obtained. In this insulating sheet with wiring 10, electrical connection between the back electrode type solar cells 30 can be simplified, and the n-type electrode connection wiring 2 a and the p-type electrode connection wiring 2 b can be reliably insulated. The insulating sheet with wiring 10 is obtained. Moreover, since the insulating base material 1 also serves as a sealing material during the production of the solar cell module 40, the production of the solar cell module 40 can be simplified.

  Moreover, in this Embodiment, the back electrode type solar cell 30 and the wiring 2 are obtained by heat treatment when joining the back electrode type solar cell 30 and the wiring 2 on the insulating base material 1 with a metal paste. Is formed as an integrated structure. Moreover, since the insulating base material 1 is cured and contracted, the adhesiveness of the insulating base material 1 is once lost, and the adhesion between the insulating base material 1 and the wiring 2 is lost.

  That is, in the present embodiment, when the back electrode type solar battery cell 30 and the wiring 2 form a structure by heat treatment, the wiring 2 is arranged in a predetermined position with the back electrode type solar battery cell 30. Since the adhesiveness is lost due to the bonding / fixing and the hardening / shrinkage of the insulating base material 1, the wiring 2 itself can maintain its original dimensional tolerance without being deformed.

  Thereafter, the insulating base material 1 that has lost its adhesiveness is heat-shrinked and the temperature is lowered, whereby the insulating base material 1 is thermally contracted and the surface adhesiveness is restored. Then, the structure is bonded again to the insulating base material 1 that has returned to a predetermined size due to the adhesiveness of the surface of the insulating base material 1 while maintaining the original dimensional tolerance, and is insulated with the photovoltaic cell integrated wiring. A sheet 20 is obtained.

  Thereby, in this Embodiment, the optimal design regarding the dimension of the wiring 2 can be performed, without worrying about the dimensional tolerance by the deformation | transformation of the insulating base material 1 by heat processing. Therefore, even when the insulating substrate 1 is enlarged to produce a large-sized solar cell module, the dimensional tolerance between the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b is increased. In addition, sufficient insulation can be maintained between the n-type electrode connection wiring 2a and the p-type electrode connection wiring 2b.

  Moreover, in the insulation sheet 20 with the photovoltaic cell integrated wiring according to the present embodiment, a metal paste is used for the connection between the back electrode type photovoltaic cell 30 and the wiring 2 without using a conductive adhesive. . For this reason, the resistance value of the connection between the back electrode type solar cell 30 and the wiring 2 can be kept low as in the case of the conventional solder connection, and the current loss degree is extremely small.

  Further, in the present embodiment, the solar cell module 40 is obtained by sandwiching the insulating sheet 20 with wiring integrated with solar cells between the back sheet 42 and the transparent resin 44 and further laminating the transparent substrate 41. can get.

  Further, by using the insulating sheet with wiring 10 and the insulating sheet 20 with integrated wiring of solar cells according to the present embodiment, solar cells necessary for one solar cell module can be arranged all at once. Can be produced. For this reason, it is possible to reduce the number of manufacturing steps, cost, and time as compared with the case where a miniaturized insulating sheet is once manufactured and the insulating sheet is further connected to manufacture a solar cell module.

  Therefore, according to the present embodiment, the n-type electrode connection wiring 2 a and the p-type electrode connection wiring 2 b are reliably insulated, and are caused by the connection between the back electrode type solar cell 30 and the wiring 2. Thus, the high-quality insulating sheet 10 with wiring, the solar cell integrated wiring insulating sheet 20, and the solar cell module 40 that can be applied to a large-area solar cell module with low current loss can be obtained at low cost.

  As described above, the insulating sheet with wiring according to the present invention is useful for realizing a solar cell module having excellent insulation between wirings and excellent current characteristics.

DESCRIPTION OF SYMBOLS 1 Insulating base material 2 Wiring 2a N-type electrode connection wiring 2b P-type electrode connection wiring 2c Wiring connection part 10 Insulation sheet | seat with wiring 20 Insulation sheet | seat with solar cell integrated wiring 30 Back surface electrode type solar cell 31 Semiconductor substrate 32 Antireflection film 33 Passivation film 34 n-type impurity diffusion region 35 p-type impurity diffusion region 36 n-type electrode 37 p-type electrode 40 solar cell module 41 transparent substrate 42 back sheet 43 transparent resin 44 transparent resin U unit region

Claims (12)

An insulating sheet with wiring provided with wiring to which electrodes of a plurality of solar cells are electrically connected,
An insulating base material made of a resin that has adhesiveness on the surface at normal temperature and contracts by heating to lose the adhesiveness of the surface;
The electrode connection wiring formed in a pattern corresponding to the pattern of the electrode in a plurality of unit areas corresponding to the shape of the solar battery cell on one surface side of the insulating base material, and formed in the unit area A wiring connection part that electrically connects the electrode connection wirings, and a wiring that is integrated and formed on one surface side of the insulating substrate;
With
The wiring is adhered to the surface of the insulating base material by the adhesiveness of the surface of the insulating base material,
Insulation sheet with wiring. The insulating substrate is made of a thermosetting resin;
The insulating sheet with wiring according to claim 1. The insulating base material includes ethylene vinyl acetate resin, polyvinyl butyral resin, epoxy resin, acrylic resin, urethane resin, olefin resin, polyester resin, silicone resin, polystyrene resin, polycarbonate resin and Consisting of at least one selected from the group consisting of rubber-based resins,
The insulating sheet with wiring according to claim 2. The said electrode connection wiring in the insulating sheet with wiring as described in any one of Claims 1-3, and the said electrode of the back electrode type photovoltaic cell which has an electrode only in the back surface on the opposite side to a light-receiving surface. Being electrically connected,
An insulation sheet with wiring integrated with solar cells. The electrode connection wiring and the electrode are connected by a low-temperature sintered metal paste having a heating temperature of 200 ° C. or lower,
The insulating sheet with solar cell integrated wiring according to claim 4. An insulating sheet with solar cell integrated wiring according to claim 4 or 5,
A light-receiving surface side protective member provided via a transparent sealing material on the light-receiving surface side of the back electrode type solar cell in the insulating sheet with wiring integrated into the solar cell;
A back surface side protective member provided on the back surface opposite to the light receiving surface in the insulating sheet with wiring integrated with solar cells via the insulating substrate;
A solar cell module comprising: A method of manufacturing an insulating sheet with wiring comprising wiring to which electrodes of a plurality of solar cells are electrically connected,
Forming a wiring pattern in which a plurality of electrode connection wirings having a pattern corresponding to the pattern of the electrodes and a wiring connection part for electrically connecting the electrode connection wirings are integrated;
The wiring pattern is adhered to one surface side of an insulating substrate made of a resin that has adhesiveness on the surface at the normal temperature and contracts by heating to lose the adhesiveness of the surface. Process,
The manufacturing method of the insulating sheet with wiring characterized by including this. The insulating substrate is made of a thermosetting resin;
The manufacturing method of the insulating sheet with wiring of Claim 7 characterized by these. The insulating base material includes ethylene vinyl acetate resin, polyvinyl butyral resin, epoxy resin, acrylic resin, urethane resin, olefin resin, polyester resin, silicone resin, polystyrene resin, polycarbonate resin and Consisting of at least one selected from the group consisting of rubber-based resins,
The manufacturing method of the insulating sheet with wiring of Claim 8 characterized by these. An insulating sheet with wiring production step of producing an insulating sheet with wiring by the method for producing an insulating sheet with wiring according to any one of claims 7 to 9,
A connection step of electrically connecting the electrode connection wiring in the insulating sheet with wiring and the electrode of the back electrode type solar cell having an electrode only on the back surface opposite to the light receiving surface;
Including
The connecting step includes
In the state in which a metal paste is interposed between the electrode connection wiring and the electrode to align the electrode connection wiring and the electrode, the insulating sheet with wiring and the plurality of back electrode solar cells A step of arranging
A heating step of joining the electrode connection wiring and the electrode by heating the insulating sheet with wiring and the plurality of back electrode type solar cells;
Having
The manufacturing method of the insulation sheet | seat with a photovoltaic cell integrated wiring characterized by these. The metal paste is a low-temperature sintered metal paste having a heating temperature of 200 ° C. or lower,
The manufacturing method of the insulation sheet with a photovoltaic cell integrated wiring of Claim 10 characterized by these. A step of producing an insulating sheet with wiring integrated with solar cells by the method for manufacturing an insulating sheet with wiring integrated with solar cells according to claim 10 or 11,
A step of disposing a light-receiving surface side protection member via a transparent sealing material on the light-receiving surface side of the back electrode type solar cell in the insulating sheet with wiring integrated with a solar cell;
A step of disposing a back surface side protective member on the back surface opposite to the light receiving surface in the insulating sheet with wiring integrated with solar cells;
By heating and integrating the light-receiving surface side protection member, the insulating sheet with solar cell integrated wiring, and the back surface protection member in a pressure-bonded state, the sealing material and the insulating base material Forming a solar cell module in which the insulating sheet with the solar cell integrated wiring is sealed between,
The manufacturing method of the solar cell module characterized by including.