JP2013065708A - Solar cell module, back sheet for solar cell module, spacer for arrangement between solar cells, and manufacturing method of solar cell module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a solar cell module which effectively reflects light entering a gap between solar cells to surfaces of the solar cells thereby improving the light utilization efficiency and the generation efficiency, a back sheet for the solar cell module, a spacer for arrangement between the solar cells, and a manufacturing method of the solar cell module.SOLUTION: A back sheet included in a solar cell module of this invention comprises: a sheet body; and a protruding body protruding from the front surface side of the sheet body and disposed at a gap between the solar cells. The protruding body comprises: a base portion ranging a surface of the sheet body to a surface position of the solar cell; and a protruding portion extending from the base portion to the front surface side. The protruding portion has a reflection surface which inclines over an area ranging from a protruding end edge to the base portion side so as to approach the adjacent solar cell side in a plane view.

Description

  The present invention relates to a solar cell module capable of improving power generation efficiency by increasing the utilization factor of light, a back sheet for a solar cell module, a spacer for arranging solar cells, and a method for manufacturing the solar cell module.

  In recent years, solar power generation as a clean energy source has attracted attention due to increasing awareness of environmental problems such as global warming, and solar cells having various forms have been developed. This solar cell is generally composed of a plurality of solar cell modules obtained by packaging a plurality of solar cells wired in series or in parallel.

  As shown in FIG. 8, a general structure of the solar cell module 41 includes a light-transmitting substrate 42 made of glass or the like, a surface-side filler layer 43 made of a thermoplastic resin, and a plurality of photovoltaic elements. The solar battery cell 44, a back surface side filler layer 45 made of a thermoplastic resin, and a solar cell module back sheet 46 (hereinafter also simply referred to as a back sheet) are integrally molded.

  The solar cell module 41 generates power by using solar rays incident on the light receiving surface of the solar battery cell 44 from the light incident surface side. However, in such a solar cell module 41, normally, adjacent solar cells 44 are arranged at a predetermined interval, so that the solar rays incident on the gaps between the solar cells 44 are incident on the solar cells 44. There is a problem that the light is emitted from the back side of the solar cell module 41 without being incident on the light receiving surface and is not effectively used for power generation.

  In order to solve such a problem, in a solar cell module including a plurality of front and back double-sided incident solar cells arranged with a gap, a back surface side translucent member (back sheet) having a rough surface formed thereon is used as a solar cell. A solar cell module arranged on the back side of the cell has been proposed (see JP-A-11-307791). In this solar cell module, a light-receiving surface on the back surface of the solar cell is configured to form light with an uneven surface of the translucent member corresponding to the gap between the adjacent solar cells, so that the light incident on the gap between the solar cells is received. It can be reflected toward. Therefore, the said solar cell module can utilize this reflected light for electric power generation, and can raise the utilization factor of light.

  However, in this solar cell module, an uneven surface is formed on the back surface side translucent member disposed on the back surface side of the adjacent solar cell, and the reflected light is efficiently reflected on the surface of the solar cell. I can't. Therefore, this solar cell module has a problem that the power generation rate cannot be increased by effectively increasing the amount of incident light on the light receiving surface having high conversion efficiency provided on the surface side of the solar cell.

Japanese Patent Application Laid-Open No. 11-307791

  This invention is made | formed in view of such a situation, and the utilization efficiency of light is improved by reflecting the solar beam which injects into the clearance gap between adjacent photovoltaic cells on the surface of a photovoltaic cell effectively. It aims at providing the manufacturing method of the solar cell module which can raise and improve electric power generation efficiency, the back sheet | seat for solar cell modules, the spacer for arrangement | positioning between solar cells, and a solar cell module.

The invention made to solve the above problems is
A solar cell module comprising a plurality of solar cells arranged with gaps, and a solar cell module backsheet disposed on the back surface side,
The solar cell module backsheet is
The seat body,
Protruding from the surface side of the sheet body, and provided with a protruding body disposed in the gap between the solar cells,
The ridges are
The base part from the surface of the sheet body to the surface position of the solar battery cell,
With a projecting part extending from the base part to the surface side,
The projecting portion has a reflecting surface that is inclined from the projecting edge to the base portion side and is inclined so as to approach the adjacent solar cell side.

  The solar cell module includes a ridge protruding from the surface side of the sheet main body of the solar cell module backsheet, and the ridge extends from the surface of the sheet main body to the surface position of the solar cell. A reflection part that includes a base part and a projecting part extending from the base part to the surface side, and the projecting part is inclined from the projecting edge to the base part side and close to the adjacent solar cell side. Has a surface. Therefore, the solar cell module effectively makes light incident on the gap between the solar cells incident on the reflection surface formed on the surface side of the surface position of the solar cells, and effectively toward the surface of the solar cells. Can be reflected. As a result, the solar cell module can improve power generation efficiency by effectively increasing the utilization factor of light.

  In the solar cell module, it is preferable that the protruding portion includes a pair of the reflecting surfaces, and the cross-sectional shape perpendicular to the protruding body forming direction is a triangle. Thereby, the light which injects into the clearance gap between adjacent photovoltaic cells can be reflected with a pair of reflective surface, and the utilization factor of light can be improved greatly.

  When the cross-sectional shape perpendicular to the convex body forming direction is a triangle, the triangle may be a substantially isosceles triangle. Thereby, incident light can be suitably reflected with respect to any solar battery cell arranged adjacently.

  The solar cell module may have an average inclination angle of the reflecting surface of 30 ° or more and 75 ° or less. Thereby, the incident light can be suitably reflected on the surface of the adjacent solar battery cell.

  The said solar cell module is good in the height of the said protrusion part being 10 micrometers or more. Thereby, the height direction area of a reflective surface can be enlarged, and the quantity of the light reflected by the surface of a photovoltaic cell can be increased.

  The solar cell module may include a light-transmitting substrate disposed on the surface side of the plurality of solar cells with a predetermined interval, and the protruding portion may substantially contact the back surface of the light-transmitting substrate. . Thereby, the amount of light reflected by the reflecting surface can be increased, and as a result, the amount of light reflected by the surface of the solar battery cell can be increased.

  The said solar cell module is good in the distance of the said protrusion part and a photovoltaic cell being 1/3 or less of the clearance gap between photovoltaic cells. Thereby, the light which injects into the clearance gap between adjacent photovoltaic cells can be made to inject into a reflective surface effectively.

  The said solar cell module is good in the said reflective surface being white. Thereby, the diffuse reflectance of the incident light can be increased, and as a result, the light incident on the surface of the solar battery cell can be increased.

  In the solar cell module, the reflection surface may be a mirror surface. Thereby, the regular reflectance of the incident light can be increased, and as a result, the light incident on the surface of the solar battery cell can be increased.

  In the solar cell module, the protruding portion may contain a polyolefin resin as a main component. Such polyolefin resin is excellent in adhesiveness with the ethylene-vinyl acetate copolymer (EVA) usually used for the back surface side filler layer of the solar cell module, and has good hydrolysis resistance. Therefore, the said solar cell module can improve durability and can promote the prolongation of a use period.

  The polyolefin resin contained in the protruding portion as a main component is preferably polyethylene. Such polyethylene has high adhesiveness with an ethylene vinyl acetate copolymer (EVA) usually used for the back side filler layer of the solar cell module, and in addition, various functions such as hydrolysis resistance, heat resistance, and weather resistance. Good balance between price and price.

  The solar cell module further includes a connection line that is disposed between the solar cells and electrically connects the solar cells, and the protruding body is provided with a connection line of the solar cells. It is good to arrange | position along the side edge which is not. Thereby, a convex body can be provided in the part which does not contribute to electric power generation, and electric power generation efficiency can be improved effectively.

Another invention made to solve the above problems is as follows:
A solar cell module backsheet disposed on the back side of a solar cell module in which a plurality of solar cells are arranged with gaps,
The seat body,
A protruding body protruding from the surface side of the seat body,
A back sheet for a solar cell module, wherein the convex body has a reflective surface inclined at an acute angle with respect to the planar direction of the sheet main body at least in the vicinity of the protruding edge.

  As for the said solar cell module backsheet, the said reflective surface is formed in the surface side rather than the surface position of the photovoltaic cell. Therefore, the solar cell module backsheet causes light incident on the gaps between the solar cells to enter the reflecting surface formed on the surface side of the surface position of the solar cells, and toward the surface of the solar cells. It can be reflected effectively. As a result, the solar cell module backsheet can improve the power generation efficiency by effectively increasing the utilization factor of light.

Moreover, another invention made in order to solve the said subject is:
An elongated base portion in which the bottom and top sides of the cross-sectional shape are provided substantially in parallel;
With the upper side of the base portion as the base, and a long protruding portion having a triangular cross-sectional shape,
At least one side surface of the protruding portion is formed as a reflective surface inclined at an acute angle with respect to the bottom surface.

  As for the spacer for arrangement | positioning between the said photovoltaic cells, the said protrusion part is formed in the surface side rather than the surface position of the photovoltaic cell. Therefore, the spacer for arranging the solar cells makes the light incident on the gap between the solar cells incident on the reflection surface formed on the surface side of the surface position of the solar cells, and enters the surface of the solar cells. Can be effectively reflected. As a result, the inter-solar cell arrangement spacer can improve power generation efficiency by effectively increasing the light utilization rate.

Yet another invention made to solve the above problems is as follows:
A first lamination step of laminating a back side filler on the front side of the solar cell module backsheet;
A second laminating step of laminating solar cells on the surface side of the back side filler so that the side edges are along the ridges of the solar cell module backsheet;
A third lamination step of laminating a surface-side filler and a translucent substrate in this order on the surface side of the solar battery cell;
It is a manufacturing method of a solar cell module having a laminating step of thermally fusing a back sheet for a solar cell module, a back surface side filler, a solar cell, a front surface side filler, and a translucent substrate, which are sequentially laminated.

  The manufacturing method of the said solar cell module should just arrange | position a photovoltaic cell so that a side edge may follow the convex body of the solar cell module backsheet, and can position a photovoltaic cell easily and reliably. . According to the method for manufacturing the solar cell module, since the protrusions can be reliably disposed in the gaps between the solar cells, the light incident on the gaps between the solar cells is reflected on the solar cell by the reflection surface of the protrusions. It can be effectively reflected on the surface of the cell. Therefore, according to the manufacturing method of the solar cell module, it is possible to easily manufacture a solar cell module whose power generation efficiency is improved by increasing the light utilization rate.

  Moreover, the mounting process which mounts the spacer for arrangement | positioning between solar cells of Claim 14 on the surface side of the flat sheet | seat back sheet for solar cell modules, and the said spacer for arrangement | positioning between solar cells is mounted A first stacking step of laminating a back surface side filler on the surface side of the back sheet for the solar cell module, and the back surface side filler so that the side edges are aligned with the spacers between the solar cells. A second lamination step of laminating on the surface side of the solar cell, a third lamination step of laminating the surface-side filler and the light-transmitting substrate in this order on the surface side of the solar cell, and between the solar cells sequentially laminated A solar cell module manufacturing method comprising: a back sheet for a solar cell module on which an arrangement spacer is placed; a back surface side filler; a solar cell; a front surface side filler; According to May be provided solar cell as side edge extends along the cell between distribution 設用 spacers can be positioned solar cell easily and reliably. According to the method for manufacturing the solar cell module, the spacers for arranging the solar cells can be surely arranged in the gaps between the solar cells, so that the light incident on the gaps between the solar cells is transmitted between the solar cells. The reflective surface of the spacer for arrangement can effectively reflect the surface of the solar battery cell. Therefore, according to the manufacturing method of the solar cell module, it is possible to easily manufacture a solar cell module whose power generation efficiency is improved by increasing the light utilization rate.

  In the present invention, “front side” means the side where light is incident on the solar cell module, and “back side” means the side opposite to the front side.

  As described above, the solar cell module, the solar cell module backsheet, and the inter-solar cell spacer for the solar cell module according to the present invention allow solar light incident on the gap between adjacent solar cells to be applied to the surface of the solar cell. By reflecting effectively, the utilization efficiency of light can be improved and the power generation efficiency can be improved. Moreover, according to the method for manufacturing a solar cell module of the present invention, it is possible to easily manufacture a solar cell module with improved power generation efficiency by increasing the light utilization rate.

It is typical sectional drawing which shows the solar cell module backsheet which concerns on one Embodiment of this invention. It is a flowchart which shows the manufacture procedure of the solar cell module using the solar cell module backsheet of FIG. It is typical sectional drawing which shows the manufacturing process of the solar cell module of FIG. It is typical sectional drawing which shows the solar cell module using the solar cell module backsheet of FIG. It is a typical top view which shows the solar cell module of FIG. It is typical sectional drawing which shows the solar cell module which concerns on the form different from the solar cell module of FIG. It is a figure which shows an example of the shape of the protruding item | line body of this invention, and the spacer for arrangement | positioning between photovoltaic cells. It is a typical fragmentary sectional view which shows the conventional common solar cell module.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[First embodiment]
<Back sheet 1 for solar cell module>
The solar cell module backsheet 1 is disposed on the back side of a solar cell module in which a plurality of solar cells are arranged with gaps. The solar cell module backsheet 1 includes a sheet main body 2 and a ridge 3 protruding from the surface side of the sheet main body 2.

(Sheet body 2)
The sheet main body 2 is a laminate including the heat sealing layer 4, the intermediate resin layer 5, and the back surface side resin layer 6 in this order from the front surface side to the back surface side. An adhesive layer 7 is disposed between the heat-sealing layer 4 and the intermediate resin layer 5 and between the intermediate resin layer 5 and the back surface side resin layer 6. The heat sealing layer 4 and the intermediate resin layer 5, and the intermediate resin layer 5 and the back surface side resin layer 6 are laminated and bonded via an adhesive layer 7.

(Heat-fusion layer 4)
The heat-sealing layer 4 is a resin layer that is provided on the outermost surface side of the sheet main body 2 and melts when heated to form a solar cell module by laminating and bonding the back sheet 1 for the solar cell module. The heat sealing layer 4 is formed with a synthetic resin as a main component.

  The synthetic resin as the main component of the heat-fusible layer 4 is not particularly limited, and is a polyolefin resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer (ABS resin), Polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyester resin, polyamide resin, polyimide resin, polyamideimide resin, polyarylphthalate resin, silicone resin, polysulfone Resin, polyphenylene sulfide resin, polyethersulfone resin, polyurethane resin, acetal resin, cellulose resin and the like. Especially, as a synthetic resin of the main component of the heat sealing | fusion layer 4, polyolefin resin is used suitably. Such polyolefin resin is excellent in adhesiveness with an ethylene-vinyl acetate copolymer (EVA) usually used for the back side filler layer, and has good hydrolysis resistance. Therefore, the heat sealing | fusion layer 4 can improve durability of a solar cell module and can prolong the use period of a solar cell module by containing polyolefin resin as a main component.

  Examples of the polyolefin resin include copolymers of olefins such as polyethylene (for example, high density polyethylene and low density polyethylene), polypropylene, and ethylene and other monomers, for example, copolymer of ethylene and unsaturated carboxylic acid ester. Copolymer (for example, ethylene-vinyl acetate copolymer (EVA), ethylene-methyl acrylate copolymer, ethylene-methyl methacrylate copolymer, etc.), copolymer of ethylene and unsaturated carboxylic acid (for example, ethylene-acrylic) Acid copolymers, ethylene-methacrylic acid copolymers, etc.), ionomer resins and the like. Among these, the adhesion to the back side filler layer, the hydrolysis resistance, the heat resistance, the weather resistance, etc. for various functional aspects and the balance of the price, and the adhesiveness to the back side filler layer In addition, a cyclic polyolefin resin excellent in functionality such as heat resistance, strength, weather resistance, durability, gas barrier properties, and ethylene-vinyl acetate copolymer (EVA) usually used for the back side filler layer are preferable.

  Examples of the cyclic polyolefin resin include polymers obtained by polymerizing cyclic dienes such as cyclopentadiene (and derivatives thereof), dicyclopentadiene (and derivatives thereof), cyclohexadiene (and derivatives thereof), norbornadiene (and derivatives thereof), and the like. And a copolymer obtained by copolymerizing the cyclic diene and one or more olefinic monomers such as ethylene, propylene, 4-methyl-1-pentene, styrene, butadiene, and isoprene. Among these cyclic polyolefin resins, cyclopentadiene (and derivatives thereof), dicyclopentadiene (and derivatives thereof) or norbornadiene (and derivatives thereof) such as polymers having excellent strength, heat resistance, and weather resistance are particularly preferred. preferable.

  Examples of the fluororesin include polytetrafluoroethylene (PTFE), perfluoroalkoxy resin (PFA) made of a copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether, and a copolymer of tetrafluoroethylene and hexafluoropropylene (FEP). Copolymer of tetrafluoroethylene and perfluoroalkyl vinyl ether and hexafluoropropylene (EPE), copolymer of tetrafluoroethylene and ethylene or propylene (ETFE), polychlorotrifluoroethylene resin (PCTFE), ethylene and chlorotrifluoroethylene Copolymer (ECTFE), vinylidene fluoride resin (PVDF), vinyl fluoride resin (PVF), and the like. Among these fluororesins, polyvinyl fluoride resin (PVF) and a copolymer of tetrafluoroethylene and ethylene or propylene (ETFE) which are excellent in strength, heat resistance, weather resistance and the like are particularly preferable.

  Examples of the polyester resin include polyethylene terephthalate and polyethylene naphthalate. Among these polyester-based resins, polyethylene terephthalate is particularly preferable because it has a good balance between various functions such as heat resistance and weather resistance, and price.

  In addition, as a forming material of the heat sealing | fusion layer 4, the said synthetic resin can be used 1 type or in mixture of 2 or more types. In addition, various additives and the like can be mixed in the forming material of the heat-fusible layer 4 for the purpose of improving and modifying workability, heat resistance, weather resistance, mechanical properties, dimensional stability, and the like. . Examples of the additive include a lubricant, a crosslinking agent, an antioxidant, an ultraviolet absorber, a light stabilizer, a filler, a reinforcing fiber, a reinforcing agent, an antistatic agent, a flame retardant, a flame retardant, a foaming agent, and an antifungal agent. Etc.

  The lower limit of the thickness (average thickness) of the heat-sealing layer 4 is preferably 20 μm, more preferably 50 μm. On the other hand, the upper limit is preferably 300 μm, more preferably 150 μm. When the thickness of the heat-fusible layer 4 is less than the above lower limit, the bonding between the back sheet 1 for a solar cell module and the back side filler layer may be insufficient, and when the thickness exceeds the above upper limit, This is contrary to the demand for thickness reduction and weight reduction of the battery module 11.

(Intermediate resin layer 5)
The intermediate resin layer 5 is formed with a synthetic resin as a main component. The synthetic resin as the main component of the intermediate resin layer 5 is not particularly limited, and examples thereof include the same resins as those used for the heat-sealing layer 4. Among them, the synthetic resin as the main component of the intermediate resin layer 5 is preferably a polyester resin, a fluorine resin, or a cyclic polyolefin resin having high heat resistance, strength, weather resistance, durability, gas barrier properties against water vapor, and the like. . As a material for forming the intermediate resin layer 5, the above synthetic resins can be used alone or in combination of two or more. Further, the additives and the like in the forming material of the intermediate resin layer 5 are the same as those of the heat fusion layer 4. The intermediate resin layer 5 can be manufactured by a known method such as an extrusion method such as a T-die method or an inflation method, a cast molding method, or a cutting method. The intermediate resin layer 5 may have a single layer structure or a multilayer structure of two or more layers.

  The thickness (average thickness) of the intermediate resin layer 5 is appropriately selected from the viewpoints of handleability of the solar cell module backsheet 1 and a request for thinning of the solar cell module. The lower limit of the thickness of the intermediate resin layer 5 can be, for example, 50 μm, and the upper limit of the thickness of the intermediate resin layer 5 can be, for example, 250 μm.

(Back side resin layer 6)
The back surface side resin layer 6 is formed with a synthetic resin as a main component. As the synthetic resin as the main component of the back surface side resin layer 6, the same resin as the heat-sealing layer 4 can be used, but polyethylene naphthalate (PEN) excellent in hydrolysis resistance and heat resistance is preferably used. .

  The polyethylene naphthalate is a polyester resin having ethylene naphthalate as a main repeating unit, and synthesized using naphthalenedicarboxylic acid as a main dicarboxylic acid component and ethylene glycol as a main glycol component.

  The ethylene naphthalate unit is preferably 80 mol% or more of all repeating units of the polyester. If the proportion of ethylene naphthalate units is less than 80 mol%, the hydrolysis resistance, strength, and barrier properties of polyethylene naphthalate may be reduced.

  Examples of the naphthalenedicarboxylic acid include 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, and the like. In view of surface, 2,6-naphthalenedicarboxylic acid is particularly preferable.

  The back surface side resin layer 6 is good to contain a carbodiimide compound in the polyethylene naphthalate which is a main component. Thus, by containing a carbodiimide compound, the hydrolysis resistance of the back surface side resin layer 6 improves markedly. As content of this carbodiimide compound, 0.1 mass% or more and 10 mass% or less are preferable, and 0.5 mass% or more and 3 mass% or less are especially preferable. Thus, by making content of a carbodiimide compound into the said range, the hydrolysis resistance of the back surface side resin layer 6 can be improved effectively.

  Examples of the carbodiimide compound include (a) N, N′-diphenylcarbodiimide, N, N′-diisopropylphenylcarbodiimide, N, N′-dicyclohexylcarbodiimide, 1,3-diisopropylcarbodiimide, and 1- (3-dimethylaminopropyl). And monocarbodiimides such as (3-ethylcarbodiimide) and (b) polycarbodiimide compounds such as poly (1,3,5-triisopropylphenylene-2,4-carbodiimide). Among these, N, N′-diphenylcarbodiimide and N, N′-diisopropylphenylcarbodiimide are preferable, and the hydrolysis resistance of the back surface side resin layer 6 can be further improved. Moreover, as a molecular weight of a carbodiimide compound, the range of 200-1000, especially the range of 200-600 are preferable. When the molecular weight exceeds the above upper limit, the dispersibility of the carbodiimide compound in the resin is lowered, and when the molecular weight is less than the lower limit, the scattering property of the carbodiimide compound may be increased.

  Moreover, the back surface side resin layer 6 is good to contain antioxidant in addition to the said carbodiimide compound in the polyethylene naphthalate which is a main component. Thus, by including both a carbodiimide compound and antioxidant in polyethylene naphthalate, the said hydrolysis resistance improves markedly, Furthermore, decomposition | disassembly of a carbodiimide compound can also be suppressed. As content of this antioxidant, 0.05 mass% or more and 1 mass% or less are preferable, and 0.1 mass% or more and 0.5 mass% or less are especially preferable. If the content of the antioxidant is less than the above lower limit, the effect of improving the carbodiimide degradation inhibiting function and hydrolysis resistance may be reduced, and if the content of the antioxidant exceeds the above upper limit, The color tone may be impaired. Specifically, hindered phenol compounds and thioether compounds, particularly hindered phenol compounds, are preferable as the antioxidant, and the hydrolysis resistance of the back side resin layer 6 can be effectively improved. The mass ratio of the antioxidant content to the carbodiimide compound content is preferably 0.1 or more and 1.0 or less, and particularly preferably 0.15 or more and 0.8 or less. If this mass ratio is less than the above lower limit, the effect of suppressing hydrolysis of carbodiimide itself may be insufficient. Conversely, if this mass ratio exceeds the above upper limit, the effect of suppressing hydrolysis of carbodiimide will peak. become. In addition, the addition method of a carbodiimide compound and antioxidant may be a method of kneading to polyethylene naphthalate or a method of adding to a polycondensation reaction of polyethylene naphthalate.

The terminal carboxyl group amount of polyethylene naphthalate is preferably 10 eq / T (equivalent / 10 ⁶ g) or more and 40 eq / T or less, particularly preferably 10 eq / T or more and 30 eq / T or less, more preferably 10 eq / T or more and 25 eq / T or less. If the amount of terminal carboxyl groups exceeds the above upper limit, the effect of improving hydrolysis resistance by the carbodiimide compound may be reduced, and if the amount of terminal carboxyl groups is less than the above lower limit, productivity may be reduced.

  Moreover, the back surface side resin layer 6 is good to contain aromatic polyester in addition to polyethylene naphthalate. Thus, by containing aromatic polyester in polyethylene naphthalate, knot strength, delamination resistance, mechanical strength, etc. can be improved while maintaining the hydrolysis resistance of the back surface side resin layer 6. As content of this aromatic polyester, 1 to 10 mass% is preferable. By making content of aromatic polyester into the said range, knot strength, delamination resistance, mechanical strength, etc. can be improved effectively. Specifically, the aromatic polyester is preferably a polyester obtained by copolymerizing a terephthalic acid component and 4,4'-diphenyldicarboxylic acid as a main dicarboxylic acid component and ethylene glycol as a main glycol component.

  In addition, the manufacturing method of polyethylene naphthalate is not specifically limited, Various well-known methods, such as a transesterification method and a direct esterification method, are employable. Further, the additives and the like in the forming material of the back surface side resin layer 6 are the same as those of the heat fusion layer 4.

  As a minimum of the thickness (average thickness) of back side resin layer 6, 12 micrometers is preferred and 25 micrometers is especially preferred. On the other hand, as an upper limit of the thickness of the back surface side resin layer 6, 50 micrometers is preferable and 40 micrometers is especially preferable. If the thickness of the back surface side resin layer 6 is less than the above lower limit, the effect of improving the durability of the back surface side resin layer 6 due to the hydrolysis resistance of polyethylene naphthalate may not be sufficiently exhibited, and its handling becomes difficult. Inconveniences such as these also occur. On the other hand, if the thickness of the back surface side resin layer 6 exceeds the above upper limit, it is contrary to the demand for thinning and lightening the solar cell module.

(Adhesive layer 7)
The adhesive layer 7 is disposed between the heat sealing layer 4, the intermediate resin layer 5, and the back surface side resin layer 6 that are superimposed. The heat sealing layer 4, the intermediate resin layer 5, and the back surface side resin layer 6 are bonded and fixed by the adhesive layer 7, thereby improving the strength, durability, fastness, and the like of the solar cell module backsheet 1.

  As the adhesive constituting the adhesive layer 7, an adhesive for lamination or a melt-extruded resin is used. Examples of the laminating adhesive include dry laminating adhesive, wet laminating adhesive, hot melt laminating adhesive, non-solvent laminating adhesive, and the like. Among these laminating adhesives, dry laminating adhesives that are excellent in adhesion, durability, weather resistance and the like are particularly preferable.

  The adhesive for dry laminate is not particularly limited, and is a polyvinyl acetate adhesive, a homopolymer such as ethyl acrylate, butyl, 2-ethylhexyl ester or the like, and methyl methacrylate, acrylonitrile, styrene, etc. Copolymers such as polyacrylate adhesives, cyanoacrylate adhesives, and copolymers of ethylene and monomers such as vinyl acetate, ethyl acrylate, acrylic acid, and methacrylic acid System adhesives, cellulose adhesives, polyester adhesives, polyamide adhesives, polyimide adhesives, amino resin adhesives made of urea resin, melamine resin, phenol resin adhesives, epoxy adhesives, polyurethane Adhesive, reactive (meth) acrylic adhesive, chloropre Rubber, nitrile rubber, styrene - rubber adhesive comprising a butadiene rubber, a silicone-based adhesive, an alkali metal silicate, and the like inorganic adhesive made of a low-melting-point glass or the like. Among these dry laminating adhesives, the adhesive sheet 7 can be prevented from being deteriorated due to deterioration or delamination due to long-term outdoor use of the back sheet 1 for the solar cell module, and further reduced in deterioration such as yellowing. Preferred are polyurethane adhesives, particularly polyester urethane adhesives.

  The form of the adhesive composition may be any form such as an aqueous type, a solution type, an emulsion type, and a dispersion type. The properties of the adhesive composition may be any properties such as liquid, sheet, powder, flakes, and pellets. The adhesive adhesive type may be any adhesive type such as a reactive type, a solvent volatile type, a thermal welding type, and a thermocompression bonding type.

The adhesive can be laminated by a roll coating method, a screen printing method, or the like. The amount of lamination of the adhesive is a non-volatile content is usually 0.1 to 50 g / m ^2, preferably from 0.5 to 20 g / m ^2. The thickness of the adhesive layer 7 is usually 1 to 50 μm, preferably 3 to 30 μm.

  Examples of the melt-extruded resin include polyethylene resins, polypropylene resins, acid-modified polyethylene resins, acid-modified polypropylene resins, ethylene-acrylic acid or methacrylic acid copolymers, Surlyn resins, and ethylene-vinyl acetate copolymers. One or more thermoplastic resins such as polyvinyl acetate resin, ethylene-acrylic acid ester or methacrylic acid ester copolymer, polystyrene resin, and polyvinyl chloride resin can be used. In addition, when employ | adopting the extrusion lamination method using the said melt extrusion resin, in order to acquire stronger adhesiveness, it is good to give surface treatments, such as an anchor coat process, to the lamination | stacking opposing surface of each said layer.

  Examples of the anchor coating agent used for the anchor coating treatment include a polyester anchor coating agent, a polyamide anchor coating agent, a polyurethane anchor coating agent, an epoxy anchor coating agent, a phenol anchor coating agent, and a (meth) acrylic anchor coating. Agents, polyvinyl acetate anchor coating agents, polyolefin anchor coating agents such as polyethylene aly polypropylene, and cellulose anchor coating agents.

The lower limit of the coating amount of the anchor coating agent (solid content) is preferably ^{0.1g / m 2, 1g / m} 2 is particularly preferred. In contrast, the upper limit of the amount of coating of the anchor coating agent is preferably ^{5g / m 2, 3g / m} 2 is particularly preferred. If the coating amount of the anchor coating agent is smaller than the above lower limit, the effect of improving the adhesion between the layers laminated via the adhesive layer 7 may be reduced. On the other hand, when the coating amount of the anchor coating agent exceeds the above upper limit, the strength, durability, etc. of the solar cell module backsheet 1 may be lowered.

  In the anchor coating agent, various additives such as a silane coupling agent for improving tight adhesion, an anti-blocking agent for preventing blocking, and an ultraviolet absorber for improving weather resistance are appropriately used. Can be mixed. The amount of the additive to be mixed is preferably 0.1% by weight or more and 10% by weight or less from the balance between the effect expression of the additive and the function inhibition of the anchor coating agent.

The lower limit of the amount of lamination of the adhesive layer 7 (in terms of solid content), preferably ^{1g / m 2, 3g / m} 2 is particularly preferred. In contrast, the upper limit of the lamination of the adhesive layer 7 (in terms of solid content), preferably 10 g / ^{m 2,} particularly preferably 7 g / ^{m 2.} If the lamination amount of the adhesive layer 7 is smaller than the above lower limit, sufficient adhesiveness may not be obtained. Moreover, when the lamination amount of the adhesive layer 7 exceeds the upper limit, the lamination strength and durability may be lowered.

  In addition, in the laminating adhesive or melt-extruded resin for forming the adhesive layer 7, for the purpose of improving and modifying the handling property, heat resistance, weather resistance, mechanical properties, etc., for example, a solvent, a lubricant, a crosslinking agent, Various additives such as antioxidants, ultraviolet absorbers, light stabilizers, fillers, reinforcing fibers, reinforcing agents, antistatic agents, flame retardants, flameproofing agents, foaming agents, antifungal agents, pigments and the like are mixed as appropriate. be able to.

(Projected ridge 3)
The ridge 3 has a base part 8 and a protruding part 9 extending on the surface side of the base part 8. The ridge 3 is formed in a triangular prism shape. The ridge 3 has a reflecting surface 10 that is inclined at an acute angle with respect to the planar direction of the sheet body 2 at least in the vicinity of the protruding edge. In the present embodiment, the side surface of the base portion 8 and the side surface of the protruding portion 9 are formed flush with each other, and the reflecting surface 10 is continuously formed on the side surface of the base portion 8 and the side surface of the protruding portion 9. Has been. Although it does not specifically limit as the height of the protruding item | line 3, Although it is about 200 micrometers or more and 2500 micrometers or less. Although it does not specifically limit as the height of the base part 8, It is about 190 micrometers or more and 1500 micrometers or less. Although it does not specifically limit as the height of the protrusion part 9, It is about 10 micrometers or more and 1000 micrometers or less.

  The protrusion 9 has a pair of reflecting surfaces 10 (in FIG. 1, the reflecting surface 10 formed on the left side of the protruding portion 9 is a reflecting surface 10a, and the reflecting surface 10 formed on the right side is a reflecting surface 10b. Have). The protrusion 9 has a triangular cross-sectional shape that is perpendicular to the direction in which the ridges 3 are formed. In particular, the protrusion 9 is formed so that a cross-sectional shape perpendicular to the direction in which the ridges 3 are formed is a substantially isosceles triangle.

  The average inclination angle of the reflecting surface 10 is not particularly limited, but is preferably 30 ° or more and 75 ° or less, and more preferably 40 ° or more and 65 ° or less. When the average inclination angle of the reflective surface 10 is less than the above range, the solar cell module backsheet 1 may not be able to suitably reflect the light reflected by the reflective surface 10 to the surface of the adjacent solar battery cell. On the contrary, if the average inclination angle of the reflecting surface 10 exceeds the above range, it becomes difficult to increase the planar area of the reflecting surface 10 while keeping the thickness of the solar cell module constant. The average inclination angle can be calculated based on the average angle of the imaginary line drawn from the upper end to the lower end of the reflecting surface 10.

  The reflecting surface 10 may be white. When the protrusion 3 contains a white pigment in a dispersed manner, the reflecting surface 10 can be white. The back sheet 1 for a solar cell module can increase the diffuse reflectance of incident light because the reflecting surface 10 is white, and thus can increase the light incident on the surface of the solar cell. .

  The white pigment is not particularly limited, and for example, calcium carbonate, titanium oxide, zinc oxide, lead carbonate, barium sulfate and the like can be used. Of these, calcium carbonate is preferable because of its excellent dispersibility in a resin material and relatively large effects of improving durability, heat resistance, strength, and the like. This calcium carbonate has crystal types such as calcite, aragonite, and vaterite, and any crystal type can be used. This calcium carbonate may be surface-treated with stearic acid, sodium dodecyl benzene sulfonate, silane coupling agent, titanium coupling agent, etc., and impurities such as magnesium oxide, aluminum oxide, silicon dioxide, titanium dioxide, etc. About 10% or less may be contained.

  The average particle diameter of the white pigment is preferably from 100 nm to 30 μm, particularly preferably from 300 nm to 3 μm. If the average particle size of the white pigment is smaller than the lower limit, uniform dispersion may be difficult due to aggregation or the like. On the other hand, when the average particle diameter of the white pigment exceeds the above upper limit, the effect of improving various properties such as heat resistance of the ridge 3 may be reduced.

  As content of the said white pigment, 8 to 30 mass% is preferable. When the content of the white pigment is less than the above lower limit, the effect of improving the durability, heat resistance, strength, and the like of the protrusion 3 is reduced. On the other hand, when the content of the white pigment exceeds the above upper limit, the dispersibility of the white pigment is lowered, and the strength of the ridge 3 may be lowered.

  The pigment that can be contained in the protrusion 3 is not limited to a white pigment, but in addition to the above white pigment, black pigments such as carbon black, blue pigments such as ultramarine and bitumen, and red pepper (oxidation) Iron red), red pigments such as cadmium red and molybdenum orange may be dispersedly contained.

  The reflecting surface 10 may be a mirror surface. The convex body 3 can make the reflective surface 10 a mirror surface by performing metal deposition, metal plating, or the like on the reflective surface 10 with a metal such as silver or aluminum. The back sheet 1 for a solar cell module can increase the regular reflectance of incident light by making the reflecting surface 10 a mirror surface, and thus can increase the light incident on the surface of the solar cell. .

  The ridge 3 is formed with a synthetic resin as a main component. As the main component of the ridge 3, the same resin as that used for the heat-sealing layer 4 can be used. Especially, as a synthetic resin of the main component of the protruding item | line 3, the polyolefin-type resin is used suitably. Such polyolefin resin is excellent in adhesiveness with an ethylene-vinyl acetate copolymer (EVA) usually used for the back side filler layer, and has good hydrolysis resistance. Therefore, the protrusion 3 can improve the durability of the solar cell module and promote the prolongation of the use period of the solar cell module by containing the polyolefin resin as a main component. Among the above-mentioned polyolefin-based resins, the synthetic resin as the main component of the ridges 3 includes various functional aspects such as adhesion to the back side filler layer, hydrolysis resistance, heat resistance, weather resistance, and price. A polyethylene having a good surface balance and a cyclic polyolefin resin excellent in functionality such as heat resistance, strength, weather resistance, durability, gas barrier properties in addition to adhesion to the back side filler layer are preferred. As a material for forming the ridges 3, one or more of the above synthetic resins can be used. Further, the additives and the like in the forming material of the ridge 3 are the same as those of the heat-sealing layer 4.

  The glass transition temperature of the ridge 3 is not particularly limited, but is preferably 150 ° to 200 °, and more preferably 160 ° to 180 °. If the glass transition temperature of the ridges 3 is less than the above range, there is a high possibility that the shape of the ridges 3 will change when heat-sealing with the back-side filler layer. On the contrary, when the glass transition temperature of the protrusion 3 exceeds the above range, the melt viscosity of the resin becomes high and the moldability may be deteriorated.

  The ridge 3 is formed by laminating a synthetic resin on a sheet mold having an inverted shape of the surface of the thermal fusion layer 4 disposed on the back surface of the ridge 3 and the ridge 3, and peeling the sheet mold. Or by a known method such as an injection molding method in which a molten resin is injected into a mold having an inverted shape of the surface of the heat-bonding layer 4 disposed on the back surface side of the protrusions 3 and the protrusions 3. It can be manufactured integrally with the fusion layer 4.

<Method for Manufacturing Back Sheet 1 for Solar Cell Module>
As a method for producing the solar cell module backsheet 1, generally, an adhesive is applied to one of the laminated opposing surfaces of the heat-fusible layer 4, the intermediate resin layer 5, and the backside resin layer 6 by roll coating, gravure. Examples thereof include a production method in which coating is performed by means such as a roll coating method and a kiss coating method, and the other laminated facing surface is bonded to the coating surface.

<Method for Manufacturing Solar Cell Module 11>
With reference to FIG.2 and FIG.3, the manufacturing method of the solar cell module 11 by which the solar cell module backsheet 1 is arrange | positioned by the back surface side is demonstrated. As a manufacturing method of the solar cell module 11, as shown in FIG. 2, the 1st lamination process (STEP1), the 2nd lamination process (STEP2), the 3rd lamination process (STEP3), and the lamination process (STEP4) have.

  A 1st lamination process (STEP1) is a process of laminating | stacking a back surface side filler on the surface side of the backsheet 1 for solar cell modules. In STEP1, as shown to Fig.3 (a), the solar cell module backsheet 1 is mounted so that the protruding item | line 3 may become the surface side, and a sheet-like back surface side filler is laminated | stacked on this.

  A 2nd lamination process (STEP2) is a process of laminating | stacking the photovoltaic cell 13 on the surface side of a back surface side filler so that a side edge may follow the protruding item | line 3 of the backsheet 1 for solar cell modules. In STEP 2, as shown in FIG. 3B, the surface of the base portion 8 is formed up to the surface side of the solar battery cell 13, and the protruding portion 9 is located on the surface side of the surface position of the solar battery cell 13. The solar battery cells 13 are stacked on each other.

  A 3rd lamination process (STEP3) is a process of laminating | stacking the surface side filler and the translucent board | substrate 15 in this order on the surface side of the photovoltaic cell 13 arrange | positioned by STEP2. In STEP3, as shown in FIG.3 (c), the sheet-like surface side filler is laminated | stacked on the surface side of the photovoltaic cell 13 laminated | stacked by STEP2, and the translucent board | substrate 15 is laminated | stacked further on this.

  The laminating step (STEP 4) is a step in which the solar cell module back sheet 1, the back surface side filler, the solar cells 13, the front surface side filler, and the translucent substrate 15 that are sequentially laminated are thermally fused. STEP 4 is performed by a vacuum heating lamination method or the like in which the back sheet 1 for the solar cell module, the back surface side filler, the solar battery cell 13, the front surface side filler, and the translucent substrate 15 are integrated by vacuum suction and thermocompression bonded. Is called. In the solar battery module 11, the back side filler and the front side filler are filled around the solar battery cell 13 as STEP 4 to form a back side filler layer and a front side filler layer.

  In the method of manufacturing the solar cell module 11, for the purpose of improving the adhesion between the respective layers, (a) applying a heat-melt adhesive, a solvent-type adhesive, a photo-curing adhesive, etc. b) Corona discharge treatment, ozone treatment, low-temperature plasma treatment, glow discharge treatment, oxidation treatment, primer coat treatment, undercoat treatment, anchor coat treatment, etc. can be performed on the opposite surfaces of each laminate. Moreover, as a manufacturing method of the solar cell module 11, on the translucent board | substrate 15, the surface side filler, the photovoltaic cell 13, the back surface side filler, and the solar cell module backsheet 1 are laminated | stacked one by one. It can also be manufactured.

<Solar cell module 11>
Next, the solar cell module 11 will be described with reference to FIG. The solar cell module 11 includes a translucent substrate 15, a front surface side filler layer 14, a plurality of solar cells 13 as photovoltaic elements, a back surface side filler layer 12, and a solar cell module backsheet 1. Are stacked in this order from the surface side.

(Translucent substrate 15)
The translucent substrate 15 is laminated on the outermost surface side, and (a) has transparency and electric insulation against sunlight, (b) mechanical, chemical and physical strength, specifically Has excellent weather resistance, heat resistance, durability, water resistance, gas barrier properties against water vapor, wind pressure resistance, chemical resistance, fastness, (c) high surface hardness, and accumulation of dirt, dust, etc. on the surface It is required to have excellent antifouling properties.

  As a material for forming the translucent substrate 15, glass and synthetic resin are used. Synthetic resins used for the translucent substrate 15 include, for example, polyethylene resins, polypropylene resins, cyclic polyolefin resins, fluorine resins, polystyrene resins, acrylonitrile-styrene copolymers (AS resins), and acrylonitrile monomers. Butadiene-styrene copolymer (ABS resin), polyvinyl chloride resin, fluorine resin, poly (meth) acrylic resin, polycarbonate resin, polyester resin such as polyethylene terephthalate, polyethylene naphthalate, various nylons, etc. Polyamide resin, polyimide resin, polyamideimide resin, polyaryl phthalate resin, silicone resin, polyphenylene sulfide resin, polysulfone resin, acetal resin, polyethersulfone resin, polyurethane resin Fat, and cellulosic resins. Among these resins, fluorine resins, cyclic polyolefin resins, polycarbonate resins, poly (meth) acrylic resins, or polyester resins are particularly preferable.

  In the case of the translucent substrate 15 made of synthetic resin, (a) transparent deposition of an inorganic oxide such as silicon oxide or aluminum oxide on one surface by the PVD method or the CVD method for the purpose of improving gas barrier properties and the like. (B) For the purpose of improving and modifying processability, heat resistance, weather resistance, mechanical properties, dimensional stability, etc., for example, lubricants, crosslinking agents, antioxidants, ultraviolet absorbers, charging It is also possible to contain various additives such as an inhibitor, a light stabilizer, a filler, a reinforcing fiber, a reinforcing agent, a flame retardant, a flame retardant, a foaming agent, a fungicide, and a pigment.

  The thickness of the translucent substrate 15 is not particularly limited, and is appropriately selected depending on the material to be used so as to have required strength, gas barrier properties, and the like. The thickness of the synthetic resin translucent substrate 15 is preferably 6 μm or more and 300 μm or less, and particularly preferably 9 μm or more and 150 μm or less. The thickness of the glass translucent substrate 15 is generally about 3 mm.

(Front side filler layer 14, back side filler layer 12)
The front-side filler layer 14 and the back-side filler layer 12 are filled around the solar cells 13 between the translucent substrate 15 and the solar cell module backsheet 1, and (a) the translucent substrate 15. And it has adhesiveness with the back sheet 1 for solar cell modules, scratch resistance for protecting the solar cells 13, shock absorption, and the like. In addition, the surface side filler layer 14 laminated | stacked on the surface of the photovoltaic cell 13 has transparency which permeate | transmits sunlight in addition to the said various functions, Preferably it is made colorless and transparent.

  Examples of the material for forming the front-side filler layer 14 and the back-side filler layer 12 include a fluorine-based resin, an ethylene-vinyl acetate copolymer, an ionomer resin, an ethylene-acrylic acid or methacrylic acid copolymer, a polyethylene resin, and a polypropylene. Examples thereof include acid-modified polyorene fin resins, polyvinyl butyral resins, silicone resins, epoxy resins, and (meth) acrylic resins obtained by modifying polyolefin resins such as resins and polyethylene with unsaturated carboxylic acids such as acrylic acid. . Among these synthetic resins, fluorine resins, silicone resins, or ethylene-vinyl acetate resins that are excellent in weather resistance, heat resistance, gas barrier properties, and the like are preferable.

  Moreover, as a forming material of the surface side filler layer 14 and the back surface side filler layer 12, the thermoreversible crosslinkable olefin polymer composition shown by Unexamined-Japanese-Patent No. 2000-34376, specifically, (a) non A modified olefin polymer modified with a saturated carboxylic acid anhydride and an unsaturated carboxylic acid ester, wherein the average number of bonds of carboxylic acid anhydride groups per molecule is 1 or more, and the modified olefin polymer A modified olefin polymer in which the ratio of the number of carboxylic acid ester groups to the number of carboxylic acid anhydride groups in the coalescence is 0.5 to 20; and (b) a hydroxyl group-containing polymer having an average number of hydroxyl groups per molecule of 1 or more. And those having a ratio of the number of hydroxyl groups in the component (b) to the number of carboxylic anhydride groups in the component (a) of from 0.1 to 5 are also used.

  The forming material of the front side filler layer 14 and the back side filler layer 12 may be, for example, a crosslinking agent, a thermal antioxidant, a light stabilizer, an ultraviolet absorber for the purpose of improving weather resistance, heat resistance, gas barrier properties, etc. Various additives such as an agent and a photo-antioxidant can be appropriately contained. The thicknesses of the front side filler layer 14 and the back side filler layer 12 are not particularly limited, but are preferably 100 μm or more and 1000 μm or less, and particularly preferably 250 μm or more and 600 μm or less.

(Solar cell 13)
The solar battery cell 13 is a photovoltaic element that converts light energy into electrical energy, and is disposed between the front surface side filler layer 14 and the back surface side filler layer 12. The several photovoltaic cell 13 is arrange | positioned with the clearance gap. The plurality of solar cells 13 are laid in substantially the same plane, and are electrically connected by connection lines 16 as shown in FIG. As for the photovoltaic cell 13, the surface side is made into the light-receiving surface. Examples of the solar battery cell 13 include a crystalline silicon solar electronic element such as a single crystal silicon type solar cell element and a polycrystalline silicon type solar cell element, an amorphous silicon solar cell element having a single junction type or a tandem structure type, and gallium arsenide. Group 3 to 5 compound semiconductor solar electronic devices such as (GaAs) and indium phosphorus (InP), and Group 2 to 6 compound semiconductor solar electronic devices such as cadmium tellurium (CdTe) and copper indium selenide (CuInSe ₂ ) Etc., and those hybrid elements can also be used. In addition, the front surface side filler layer 14 or the back surface side filler layer 12 is filled between the plurality of solar cells 13 without any gap.

(Back sheet for solar cell module 1)
The back sheet 1 for a solar cell module includes a sheet body 2 and a protrusion 3 that protrudes from the surface side of the sheet body 2 and is disposed in a gap between the solar cells 13. The ridge 3 has a base part 17 extending from the surface of the sheet body 2 to the surface position of the solar battery cell 13 and a protruding part 18 extending from the base part 17 to the surface side. The projecting part 18 has a reflecting surface 10 that is inclined from the projecting edge to the base part 17 side so as to be close to the adjacent solar cell 13 side. As shown in FIG. 5, the protrusion 3 is disposed along a side edge where the connection line 16 of the solar battery cell 13 is not disposed. A plurality of protrusions 3 are provided so as to protrude from the surface side of the sheet body 2. The plurality of ridges 3 are arranged so as to be parallel and opposed to each other. The base part 17 is a part corresponding to the base part 8 in FIG. 1, and the protruding part 18 is a part corresponding to the protruding part 9 in FIG. 1.

  Although it does not specifically limit as the height of the protrusion part 18, 10 micrometers or more are preferable, 20 micrometers or more are more preferable, and 50 micrometers or more are especially preferable. If the height of the protruding portion 18 is less than the above range, the area in the height direction of the reflecting surface 10 becomes small, and the amount of light reflected on the surface of the solar battery cell 13 may be reduced.

  The protruding portion 18 is preferably substantially in contact with the back surface of the translucent substrate 15. In the solar cell module 11, the projecting portion 18 is substantially in contact with the back surface side of the translucent substrate 15, so that the area in the height direction of the reflecting surface 10 can be increased and reflected by the reflecting surface 10. It is possible to increase the amount of light that is reflected and thus increase the amount of light that is reflected by the surface of the solar battery cell 13.

The distance between the ridge portion 18 and the solar cell 13 (D), is not particularly limited, one-third or less are preferred gap between the solar battery cells 13 _{(D 1),} more preferably 1/4 or less. When the distance (D) between the convex portion 18 and the solar battery cell 13 is larger than the above range, the planar area of the reflecting surface 10 is reduced, and the amount of light incident on the reflecting surface 10 may be reduced. On the other hand, when the distance (D) between the protruding portion 18 and the solar battery cell 13 is within the above range, the light incident on the gap between the adjacent solar battery cells 13 is effectively made incident on the reflecting surface 10. be able to. In addition, the said solar cell module 11 is preferable that the reflective surface 10 and the photovoltaic cell 13 are spaced apart when the reflective surface 10 is a mirror surface. The solar cell module 11 can prevent the solar cell module backsheet 1 from being charged because the reflecting surface 10 and the solar cell 13 are separated from each other.

  The solar cell module 11 includes a ridge 3 projecting from the surface side of the sheet body 2 of the solar cell module backsheet 1, and the ridge 3 is a solar cell 13 from the surface of the sheet body 2. The base part 17 extending to the surface position of the base part 17 and a projecting part 18 extending from the base part 17 to the surface side are provided, and the projecting part 18 is adjacent to the base part 17 side from the projecting edge. It has the reflective surface 10 which inclines so that it may adjoin to the photovoltaic cell 13 side. Therefore, the solar cell module 11 causes the light incident on the gaps between the solar cells 13 to enter the reflecting surface 10 formed on the surface side of the surface position of the solar cells 13, and enters the surface of the solar cells 13. Can be effectively reflected. As a result, the solar cell module 11 can improve the power generation efficiency by effectively increasing the light utilization rate. Moreover, since the said solar cell module 11 has the protrusion 3 from which the sheet | seat main body 2 of the solar cell module backsheet 1 protrudes from the surface side, the solar cell module backsheet 1 and back surface side filling The adhesion area with the agent layer 12 can be increased. As a result, the solar cell module 11 can increase the adhesive strength between the solar cell module backsheet 1 and the back surface side filler layer 12, and can improve durability.

  In the solar cell module 11, the projecting portion 18 includes a pair of reflecting surfaces 10, and the cross-sectional shape perpendicular to the direction in which the protrusion 3 is formed is formed in a triangle, so that the gap between the adjacent solar cells 13 is formed. Incident light can be reflected by the pair of reflecting surfaces 10, and the utilization factor of light can be dramatically increased.

  Since the solar cell module 11 has a substantially isosceles triangle cross-sectional shape perpendicular to the direction in which the ridges 3 are formed, any solar cell 13 that is arranged adjacent to incident light is also provided. It can be suitably reflected.

  In the solar cell module 11, the ridges 3 are arranged along the side edges where the connection lines 16 of the solar cells 13 are not arranged. It is possible to effectively increase the power generation efficiency.

  In the solar cell module backsheet 1, the reflective surface 10 is formed on the surface side of the surface position of the solar battery cell 13. Therefore, the solar cell module backsheet 1 causes the light incident on the gaps between the solar cells 13 to be incident on the reflecting surface 10 formed on the surface side of the solar cell 13 relative to the surface position of the solar cells 13. Can be effectively reflected toward the surface. As a result, the solar cell module backsheet 1 can improve power generation efficiency by effectively increasing the utilization factor of light. Moreover, since the said solar cell module backsheet 1 has the protrusion 3 protrudingly provided from the surface side of the sheet | seat main body 2, the adhesion area with the back surface side filler layer 12 can be enlarged. . As a result, the solar cell module backsheet 1 can increase the adhesive strength with the back surface side filler layer 12, and consequently improve the durability of the solar cell module 11.

  The solar cell module 11 may be manufactured by arranging the solar cells 13 so that the side edges of the solar cell module backsheet 1 are aligned with the ridges 3 of the solar cell module backsheet 1, and positioning the solar cells 13 easily and reliably. Can be done. According to the method for manufacturing the solar cell module 11, since the protrusions 3 can be reliably disposed in the gaps between the solar cells 13, the light incident on the gaps between the solar cells 13 is incident on the protrusions 3. The reflective surface 10 can effectively reflect the surface of the solar battery cell 13. Therefore, according to the manufacturing method of the said solar cell module 11, the solar cell module 11 by which the power generation efficiency was improved by raising the utilization factor of light can be manufactured easily.

[Second Embodiment]
The solar cell module 21 in FIG. 6 includes a translucent substrate 15, a front surface side filler layer 14, a plurality of solar cells 13 as photovoltaic elements, a back surface side filler layer 12, and a space between solar cells. An arrangement spacer 22 and a solar cell module backsheet 23 are provided. The translucent substrate 15, the front surface side filler layer 14, the solar battery cell 13, and the back surface side filler layer 12 are the same as the solar cell module 11 of FIG.

(Spacer 22 between solar cells)
The spacer 22 for inter-solar cell arrangement has a long base portion 24 in which the bottom and top sides of the cross-sectional shape are provided substantially parallel to each other, and the top side of the base portion 24 is a long side having a triangular cross-sectional shape. And a projecting portion 25 having a scale shape. In the inter-solar cell spacer 22, at least one side surface of the projecting portion 25 is formed as a reflective surface 26 that is inclined at an acute angle with respect to the bottom surface. The spacers 22 for arranging the solar cells are arranged in the gaps between the adjacent solar cells 13. The inter-solar cell arrangement spacers 22 are arranged along the side edges where the connection lines of the solar cells 13 are not arranged. The base 24 is formed up to the surface position of the adjacent solar battery cell 13. The side surface of the base portion 24 and the side surface of the protruding portion 25 are formed to be flush with each other. The reflection surface 26 is continuously formed on the side surface of the base portion 24 and the side surface of the protruding portion 25.

  In addition, the resin and additive which form the spacer 22 for arrangement | positioning between photovoltaic cells, the pigment which the spacer 22 for arrangement | positioning between photovoltaic cells contains, the height of the spacer 22 for arrangement | positioning between photovoltaic cells, the reflective surface 26 The shape, the height of the protruding portion 25, the distance between the protruding portion 25 and the solar battery cell 13, and the like are the same as those of the protruding body 3. The inter-solar cell spacer 22 can be manufactured by, for example, an injection molding method in which a molten resin is injected into a mold having an inverted surface shape.

(Back sheet 23 for solar cell module)
The back sheet 23 for a solar cell module is a flat laminate including the thermal fusion layer 4, the gas barrier layer 27, and the back surface side resin layer 6 in this order from the front surface side to the back surface side. An adhesive layer 7 is disposed between the heat-fusible layer 4 and the gas barrier layer 27 and between the gas barrier layer 27 and the back side resin layer 6. The heat sealing layer 4 and the gas barrier layer 27, and the gas barrier layer 27 and the back surface side resin layer 6 are laminated and bonded via the adhesive layer 7.

(Gas barrier layer 27)
The gas barrier layer 27 is a layer having a function of reducing permeation of gas such as hydrogen gas and oxygen gas. The gas barrier layer 27 includes a base film 28 and an inorganic oxide layer 29 laminated on the base film 28.

  The base film 28 is formed with a synthetic resin as a main component. As the main component synthetic resin of the base film 28, the same synthetic resin as that of the heat-sealing layer 4 is used, and in particular, polyethylene terephthalate having a good balance of various functions such as heat resistance and weather resistance and price. preferable. Further, the forming method of the base film 28 and the additives in the forming material of the base film 28 are the same as those of the heat fusion layer 4.

  As a minimum of the thickness (average thickness) of substrate film 28, 7 micrometers is preferred and 10 micrometers is especially preferred. On the other hand, the upper limit of the thickness of the base film 28 is preferably 20 μm and particularly preferably 15 μm. When the thickness of the base film 28 is less than the above lower limit, inconveniences such as curling easily occur during vapor deposition for forming the inorganic oxide layer 29, and handling becomes difficult. . On the contrary, if the thickness of the base film 28 exceeds the above upper limit, it is contrary to the demand for thinning and lightening the solar cell module.

  The inorganic oxide layer 29 is a layer for expressing gas barrier properties against oxygen, water vapor, and the like, and is formed by depositing an inorganic oxide on the back surface of the base film 28. The vapor deposition means for forming the inorganic oxide layer 29 is not particularly limited as long as the inorganic oxide can be vapor deposited on the base film 28 without causing deterioration such as shrinkage and yellowing. (A) Vacuum vapor deposition Physical vapor deposition (Physical Vapor Deposition method; PVD method) such as sputtering, ion plating, ion cluster beam, etc., (b) plasma chemical vapor deposition, thermal chemical vapor deposition, photochemical vapor A chemical vapor deposition method (Chemical Vapor Deposition method; CVD method) such as a phase growth method is employed. Among these vapor deposition methods, a vacuum vapor deposition method and an ion plating method that can form a high-quality inorganic oxide layer with high productivity are preferable.

  The inorganic oxide constituting the inorganic oxide layer 29 is not particularly limited as long as it has gas barrier properties. For example, aluminum oxide, silica oxide, titanium oxide, zirconium oxide, zinc oxide, tin oxide, oxidation Magnesium or the like is used, and among these, aluminum oxide or silica oxide having a good balance between gas barrier properties and price is particularly preferable.

  The lower limit of the thickness (average thickness) of the inorganic oxide layer 29 is preferably 3 mm, and particularly preferably 400 mm. On the other hand, the upper limit of the thickness of the inorganic oxide layer 29 is preferably 3000 mm, and particularly preferably 800 mm. If the thickness of the inorganic oxide layer 29 is smaller than the lower limit, the gas barrier property may be lowered. On the other hand, when the thickness of the inorganic oxide layer 29 exceeds the above upper limit, the flexibility of the inorganic oxide layer 29 is lowered, and defects such as cracks are likely to occur.

  The inorganic oxide layer 29 may have a single layer structure or a multilayer structure of two or more layers. Thus, by making the inorganic oxide layer 29 into a multilayer structure, the deterioration of the base film 28 is reduced by reducing the thermal load applied during vapor deposition, and the adhesion between the base film 28 and the inorganic oxide layer 29 is further reduced. The sex etc. can be improved. The vapor deposition conditions in the physical vapor deposition method and the chemical vapor deposition method are appropriately designed according to the resin type of the base film 28, the thickness of the inorganic oxide layer, and the like.

  In addition, in order to improve the close adhesion between the base film 28 and the inorganic oxide layer 29, a surface treatment may be performed on the deposition surface of the base film 28. Examples of such adhesion improving surface treatment include (a) corona discharge treatment, ozone treatment, low temperature plasma treatment using oxygen gas or nitrogen gas, glow discharge treatment, oxidation treatment using chemicals, and the like ( b) Primer coat treatment, undercoat treatment, anchor coat treatment, vapor deposition anchor coat treatment and the like. Among these surface treatments, corona discharge treatment and anchor coat treatment that improve adhesion strength with the inorganic oxide layer and contribute to the formation of a dense and uniform inorganic oxide layer are preferable. The coating amount of the anchor coating agent and the additives that can be mixed with the anchor coating agent are the same as described above.

<Method for Manufacturing Back Sheet 23 for Solar Cell Module>
As a manufacturing process of the said solar cell module backsheet 23, generally, (1) The gas barrier layer 27 manufacturing process which deposits an inorganic oxide on the back surface of the base film 28 by the said PVD method or CVD method, ( 2) Adhesive is coated on one of the laminated opposing surfaces of the heat fusion layer 4, the gas barrier layer 27 and the back side resin layer 6 by means of a roll coating method, a gravure roll coating method, a kiss coating method, etc. A stacking step of bonding the stacking facing surfaces.

<Method for Manufacturing Solar Cell Module 21>
As a manufacturing method of the solar cell module 21, a mounting process (STEP 11), a first stacking process (STEP 12), a second stacking process (STEP 13), a third stacking process (STEP 14), and a laminating process (STEP 15) have.

  The placing step (STEP 11) is a step of placing the inter-solar cell spacers 22 on the surface side of the flat solar cell module backsheet 23. STEP 11 is performed by placing the inter-solar cell spacers 22 on the surface side of the solar cell module back sheet 23 and thermally fusing them.

  The first laminating step (STEP 12) is a step of laminating a back side filler on the front side of the solar cell module back sheet 23 on which the inter-solar cell spacers 22 are placed in STEP 11. In STEP 12, the solar cell module back sheet 23 is placed so that the inter-solar cell spacers 22 are on the front side, and a sheet-like back side filler is laminated thereon.

  A 2nd lamination process (STEP13) is a process of laminating | stacking the photovoltaic cell 13 on the surface side of a back surface side filler so that a side edge may follow the spacer 22 for arrangement | positioning between photovoltaic cells. In STEP 13, the solar battery cells 13 are stacked such that the surface of the base portion 24 is formed up to the surface position of the solar battery cell 13, and the protruding portion 25 is located on the surface side of the surface position of the solar battery cell 13.

  A 3rd lamination process (STEP14) is a process of laminating | stacking the surface side filler and the translucent board | substrate 15 in this order on the surface side of the photovoltaic cell 13. FIG. In STEP14, a sheet-like surface-side filler is laminated on the surface side of the solar cells 13 laminated in STEP13, and a light-transmitting substrate 15 is further laminated thereon.

  In the laminating step (STEP 15), the solar cell module back sheet 23, the back surface side filler, the solar cell 13, the front surface side filler and the light transmitting material on which the solar cell interposing spacers 22 are sequentially stacked are placed. This is a process of thermally bonding the conductive substrate 15. STEP 15 is performed by a vacuum heating lamination method or the like in which the back sheet 23 for the solar cell module, the back surface side filler, the solar battery cell 13, the front surface side filler, and the light transmitting substrate 15 are integrated by vacuum suction and thermocompression bonded. Is called.

  In addition, in the manufacturing method of the solar cell module 21, for the purpose of improving the adhesion between the respective layers, (a) applying a heat-melt adhesive, a solvent-type adhesive, a photo-curable adhesive, and the like ( b) Corona discharge treatment, ozone treatment, low-temperature plasma treatment, glow discharge treatment, oxidation treatment, primer coat treatment, undercoat treatment, anchor coat treatment, etc. can be performed on the opposite surfaces of each laminate.

  Moreover, as a manufacturing method of the solar cell module 21, in STEP11, it does not heat-seal with the solar cell module backsheet 23 and the spacer 22 for arrangement | positioning between solar cells, but is vacuum-sucked in STEP15 like other members. May be thermocompression bonded. Furthermore, as a manufacturing method of the solar cell module 21, on the translucent substrate 15, the surface side filler, the solar cell 13, the back surface side filler, the spacer 22 for arranging between the solar cells, and the back for the solar cell module. It can also be manufactured by sequentially laminating the sheets 23.

  In the inter-solar cell spacer 22, the protruding portion 25 is formed on the surface side of the surface position of the solar cell 13. Therefore, the solar cell disposing spacer 22 causes the light incident on the gap between the solar cells 13 to be incident on the reflection surface 26 formed on the surface side of the solar cell 13 relative to the surface position of the solar cell 13. The light can be effectively reflected toward the surface of the cell 13. As a result, the inter-solar cell spacers 22 can improve power generation efficiency by effectively increasing the light utilization rate.

  The manufacturing method of the said solar cell module 21 should just arrange | position the photovoltaic cell 13 so that a side edge may follow the spacer 22 for arrangement | positioning between photovoltaic cells, and positioning the photovoltaic cell 13 easily and reliably. Can do. According to the method for manufacturing the solar cell module 21, the inter-solar cell spacers 22 can be reliably disposed in the gaps between the solar cells 21, so that the light incident on the gaps between the solar cells 13 can be reduced. The reflection surface 26 of the inter-solar cell arrangement spacer 22 can effectively reflect the surface of the solar cell 13. Therefore, according to the manufacturing method of the said solar cell module 21, the solar cell module 21 by which the power generation efficiency was improved by raising the utilization factor of light can be manufactured easily.

[Other Embodiments]
In addition, the manufacturing method of the solar cell module of this invention, the back sheet for solar cell modules, the spacer for arrangement | positioning between solar cells, and a solar cell module is implemented in the aspect which gave various change and improvement other than the said aspect. be able to. For example, as the shape of the protrusions and the spacers for arranging the solar cells, it is not necessary that the reflecting surfaces are formed on both side surfaces of the protruding portion, and the reflecting surfaces may be formed only on one side surface. . Further, the protrusions and the spacers for arranging the solar cells need not necessarily be formed in an isosceles triangle cross-sectional shape. For example, as shown in FIG. It may be formed in a right triangle shape, and as shown in (b), only the protruding portion may be formed to have an inclined reflecting surface, and as shown in (c), the reflecting surface is It may be formed in a cross-sectional arc shape. Moreover, in the said solar cell module, the protrusion and the spacer for arrangement | positioning between photovoltaic cells should just be arrange | positioned so that a formation direction and the side edge of a photovoltaic cell may follow, Four of photovoltaic cells Of the side edges, the side edges may be provided only along a pair of side edges provided in parallel to each other, or may be provided along each of the four side edges.

  The solar cell module backsheet is formed by laminating other layers (synthetic resin layers, metal layers, inorganic oxide layers, etc.) and films in addition to the thermal fusion layer, the intermediate resin layer, the gas barrier layer, and the backside resin layer. May be. Thus, by laminating other layers or films, various characteristics such as voltage resistance, gas barrier properties, weather resistance, durability, etc. can be remarkably improved. Moreover, the said solar cell module backsheet may be provided with the gas barrier layer, the intermediate | middle resin layer, and the back surface side resin layer in this order on the back surface side of the heat-fusion layer. In the solar cell module backsheet, an intermediate resin layer, a gas barrier layer, and a backside resin layer may be provided in this order on the backside of the heat-sealing layer. Moreover, the said solar cell module backsheet can also be equipped with the gas barrier layer by which the inorganic oxide layer was laminated | stacked on the surface of the base film. The back sheet for the solar cell module may use a metal stay such as an aluminum foil as a gas barrier layer.

  As described above, the solar cell module, the back sheet for solar cell module, the spacer for arranging solar cells, and the method for manufacturing the solar cell module according to the present invention have the solar rays incident on the gaps between adjacent solar cells. By effectively reflecting the surface of the solar battery cell, it is possible to improve the light utilization efficiency and improve the power generation efficiency. For example, a solar cell for a small rooftop or a small electric device such as a calculator. Preferably used.

DESCRIPTION OF SYMBOLS 1 Back sheet | seat for solar cell modules 2 Sheet | seat main body 3 Projection body 4 Thermal fusion layer 5 Intermediate resin layer 6 Back surface side resin layer 7 Adhesive layer 8 Base part 9 Protrusion part 10 Reflective surface 11 Solar cell module 12 Back surface side filler Layer 13 Solar cell 14 Surface side filler layer 15 Translucent substrate 16 Connection line 17 Base part 18 Protruding part 21 Solar cell module 22 Space between solar cells 23 Solar cell module back sheet 24 Base part DESCRIPTION OF SYMBOLS 25 Protrusion part 26 Reflecting surface 27 Gas barrier layer 28 Base film 29 Inorganic oxide layer 41 Solar cell module 42 Translucent substrate 43 Surface side filler layer 44 Solar cell 45 Back surface side filler layer 46 Back sheet | seat for solar cell modules

Claims (16)

A solar cell module comprising a plurality of solar cells arranged with gaps, and a solar cell module backsheet disposed on the back surface side,
The solar cell module backsheet is
The seat body,
Protruding from the surface side of the sheet body, and provided with a protruding body disposed in the gap between the solar cells,
The ridges are
The base part from the surface of the sheet body to the surface position of the solar battery cell,
With a projecting part extending from the base part to the surface side,
The solar cell module, wherein the projecting portion has a reflecting surface that is inclined from the projecting edge to the base site side and is close to the adjacent solar cell side.   2. The solar cell module according to claim 1, wherein the protruding portion includes a pair of the reflecting surfaces, and a cross-sectional shape perpendicular to the protruding body forming direction is a triangle.   The solar cell module according to claim 2, wherein a cross-sectional shape perpendicular to the convex body forming direction is a substantially isosceles triangle.   4. The solar cell module according to claim 1, wherein an average inclination angle of the reflecting surface is 30 ° or more and 75 ° or less. 5.   The solar cell module according to any one of claims 1 to 4, wherein a height of the protruding portion is 10 µm or more. A translucent substrate disposed on the surface side of the plurality of solar cells with a predetermined interval,
The solar cell module according to any one of claims 1 to 5, wherein the protruding portion substantially contacts the back surface of the translucent substrate.   The solar cell module according to any one of claims 1 to 6, wherein a distance between the projecting portion and the solar battery cell is 1/3 or less of a gap between the solar battery cells.   The solar cell module according to claim 1, wherein the reflecting surface is white.   The solar cell module according to claim 1, wherein the reflecting surface is a mirror surface.   The solar cell module according to any one of claims 1 to 9, wherein the protruding portion contains a polyolefin resin as a main component.   The solar cell module according to claim 10, wherein the polyolefin resin is polyethylene. Further provided between the solar cells, further comprising a connection line for electrically connecting these solar cells,
The solar cell module according to any one of claims 1 to 11, wherein the convex body is disposed along a side edge where a connection line of solar cells is not disposed. A solar cell module backsheet disposed on the back side of a solar cell module in which a plurality of solar cells are arranged with gaps,
The seat body,
A protruding body protruding from the surface side of the seat body,
The back sheet for a solar cell module, wherein the convex body has a reflective surface inclined at an acute angle with respect to the planar direction of the sheet main body at least in the vicinity of the protruding edge. An elongated base portion in which the bottom and top sides of the cross-sectional shape are provided substantially in parallel;
With the upper side of the base portion as the base, and a long protruding portion having a triangular cross-sectional shape,
At least one side surface of the protruding portion is formed as a reflective surface inclined at an acute angle with respect to the bottom surface. A first lamination step of laminating a back-side filler on the surface side of the solar cell module backsheet according to claim 13;
A second laminating step of laminating solar cells on the surface side of the back side filler so that the side edges are along the ridges of the solar cell module backsheet;
A third lamination step of laminating a surface-side filler and a translucent substrate in this order on the surface side of the solar battery cell;
A method for producing a solar cell module, comprising: a solar cell module backsheet, a back surface side filler, a solar cell, a front surface side filler, and a light transmissive substrate that are sequentially laminated. A mounting step of mounting the inter-solar cell spacer according to claim 14 on the surface side of the flat sheet for solar cell module,
A first laminating step of laminating a back surface side filler on the front surface side of the solar cell module backsheet on which the inter-solar cell spacer is placed;
A second laminating step of laminating solar cells on the surface side of the back-side filler so that the side edges of the spacers between the solar cells are aligned,
A third lamination step of laminating a surface-side filler and a translucent substrate in this order on the surface side of the solar battery cell;
Laminating step of heat-sealing back sheet for solar cell module, solar cell module, solar cell, front surface side filler and translucent substrate on which solar cell interposing spacers are sequentially stacked The manufacturing method of the solar cell module which has.

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