WO2024204490A1 - フレキシブル太陽電池 - Google Patents

フレキシブル太陽電池 Download PDF

Info

Publication number
WO2024204490A1
WO2024204490A1 PCT/JP2024/012557 JP2024012557W WO2024204490A1 WO 2024204490 A1 WO2024204490 A1 WO 2024204490A1 JP 2024012557 W JP2024012557 W JP 2024012557W WO 2024204490 A1 WO2024204490 A1 WO 2024204490A1
Authority
WO
WIPO (PCT)
Prior art keywords
flame
solar cell
retardant layer
flexible solar
layer
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2024/012557
Other languages
English (en)
French (fr)
Japanese (ja)
Inventor
智仁 宇野
和司 松島
裕樹 澤田
悠司 藤森
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Sekisui Chemical Co Ltd
Original Assignee
Sekisui Chemical Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Sekisui Chemical Co Ltd filed Critical Sekisui Chemical Co Ltd
Priority to JP2025511111A priority Critical patent/JPWO2024204490A1/ja
Publication of WO2024204490A1 publication Critical patent/WO2024204490A1/ja
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/40—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation comprising a p-i-n structure, e.g. having a perovskite absorber between p-type and n-type charge transport layers
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/50—Photovoltaic [PV] devices
    • H—ELECTRICITY
    • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
    • H10K—ORGANIC ELECTRIC SOLID-STATE DEVICES
    • H10K30/00—Organic devices sensitive to infrared radiation, light, electromagnetic radiation of shorter wavelength or corpuscular radiation
    • H10K30/80—Constructional details
    • H10K30/88—Passivation; Containers; Encapsulations

Definitions

  • the present invention relates to flexible solar cells.
  • Flexible solar cells using polyimide, polyester-based heat-resistant polymer materials or metal foil as a substrate have been attracting attention.
  • Flexible solar cells have advantages such as being thin and lightweight, making them easy to transport and install, and being impact resistant, and are manufactured, for example, by laminating multiple layers, such as a photoelectric conversion layer that generates an electric current when irradiated with light, in a thin film form on a flexible substrate.
  • the upper and lower surfaces of the flexible solar cell are sealed by laminating solar cell encapsulant sheets.
  • Patent Document 2 describes a substrate for a semiconductor device including a sheet-like aluminum base material, and an organic thin-film solar cell including this substrate for a semiconductor device.
  • the objective of the present invention is to provide a solar cell that has excellent flame retardancy in the planar direction.
  • the present invention includes the following Disclosures 1 to 12. The present invention will be described in detail below.
  • [Disclosure 1] A flexible solar cell having a power generation section and a flame-retardant layer, The thickness of the flame-retardant layer is 75 ⁇ m or more, A flexible solar cell, characterized in that a layer having a flame retardancy lower than VTM-2 in a UL94 flame test among layers disposed on the flame retardant layer has a material volume per unit area of 0.075 cm 3 /cm 2 or less.
  • Disclosure 2 The flexible solar cell according to Disclosure 1, wherein the flame-retardant layer has a flame retardancy of VTM-0 or higher in a UL94 flame test.
  • a flexible solar cell having a power generation section and a flame-retardant layer, the flame-retardant layer is a composite reinforcement material having a glass cloth and an organic resin, A flexible solar cell, characterized in that the flame-retardant layer has a thickness of 75 ⁇ m or more.
  • the flexible solar cell of the present invention has a power generating section.
  • the power generating section is a section that converts sunlight into electricity, and is composed of a substrate, an electrode, a counter electrode, a photoelectric conversion layer, an electron transport layer, a hole transport layer, etc., and has at least an electrode, a counter electrode, and a photoelectric conversion layer.
  • the term "layer” refers not only to a layer having a clear boundary, but also to a layer having a concentration gradient in which the contained elements change gradually.
  • the elemental analysis of the layer can be performed, for example, by performing FE-TEM/EDS line analysis measurement of a cross section of a solar cell to confirm the elemental distribution of a specific element.
  • the term “layer” refers not only to a flat thin-film layer, but also to a layer that can form a complex and intricate structure together with other layers.
  • the substrate is not particularly limited as long as it is flexible, and examples include resin films made of heat-resistant polymers such as polyimide and polyester, metal foils, and thin glass sheets. Of these, PET resin films are preferred.
  • the material of the electrode and the counter electrode is not particularly limited, and examples thereof include FTO (fluorine-doped tin oxide), ITO (tin-doped indium oxide), AZO (aluminum zinc oxide), IZO (indium zinc oxide), GZO (gallium zinc oxide), sodium, sodium-potassium alloy, lithium, magnesium, aluminum, magnesium-silver mixture, magnesium-indium mixture, aluminum-lithium alloy, Al/Al 2 O 3 mixture, Al/LiF mixture, etc.
  • gold, silver, titanium, molybdenum, tantalum, tungsten, carbon, nickel, chromium, etc. may also be mentioned. These materials may be used alone, or two or more of them may be used in combination.
  • the thickness of the electrode and the counter electrode is not particularly limited, but the preferred lower limit is 10 nm and the preferred upper limit is 1000 nm. If the thickness is 10 nm or more, the resistance can be suppressed while still functioning as an electrode. If the thickness is 1000 nm or less, the light transmittance can be further improved. The more preferred lower limit of the thickness of the electrode and the counter electrode is 50 nm and the more preferred upper limit is 500 nm.
  • the photoelectric conversion layer preferably contains an organic-inorganic perovskite compound represented by the general formula AMX (wherein A is an organic base compound and/or an alkali metal, M is a lead or tin atom, and X is a halogen atom).
  • a solar cell in which the photoelectric conversion layer contains the organic-inorganic perovskite compound is also called an organic-inorganic hybrid solar cell.
  • the above A is an organic base compound and/or an alkali metal.
  • the organic base compound include methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine, dipentylamine, dihexylamine, trimethylamine, triethylamine, tripropylamine, tributylamine, tripentylamine, trihexylamine, ethylmethylamine, methylpropylamine, butylmethylamine, methylpentylamine, hexylmethylamine, ethylpropylamine, ethylbutylamine, formamidine, acetamidine, guanidine, imidazole, azole, pyrrole, aziridine, azirine, azetidine, azeto, azole, imidazoline, carbazole, and ions thereof (e.
  • methylamine, ethylamine, propylamine, butylamine, pentylamine, hexylamine, formamidine, acetamidine, ions thereof, and phenethylammonium are preferred, and methylamine, ethylamine, propylamine, formamidine, and ions thereof are more preferred.
  • alkali metal include lithium, sodium, potassium, rubidium, and cesium.
  • the above M is a metal atom and is a lead or tin atom. These metal atoms may be used alone or in combination of two or more kinds.
  • the above X is a halogen atom, and examples of the halogen atom include chlorine, bromine, iodine, sulfur, and selenium. These halogen atoms may be used alone or in combination of two or more.
  • the organic-inorganic perovskite compound becomes soluble in an organic solvent, making it possible to apply the compound to inexpensive printing methods and the like.
  • X is iodine, since this narrows the energy band gap of the organic-inorganic perovskite compound.
  • the organic-inorganic perovskite compound preferably has a cubic structure in which a metal atom M is located at the body center, an organic base compound or alkali metal A is located at each vertex, and a halogen atom X is located at the face center.
  • the organic-inorganic perovskite compound is preferably a crystalline semiconductor.
  • a crystalline semiconductor means a semiconductor in which a scattering peak can be detected by measuring an X-ray scattering intensity distribution.
  • the degree of crystallinity can also be evaluated as an index of crystallization by separating the scattering peaks derived from crystalline materials and the halos derived from amorphous parts detected by X-ray scattering intensity distribution measurement by fitting, determining the intensity integrals of each, and calculating the ratio of the crystalline parts to the whole.
  • the preferred lower limit of the crystallinity of the organic-inorganic perovskite compound is 30%. When the crystallinity is 30% or more, the mobility of electrons in the organic-inorganic perovskite compound is high, and the photoelectric conversion efficiency of the solar cell is improved. The more preferred lower limit of the crystallinity is 50%, and the even more preferred lower limit is 70%.
  • Methods for increasing the crystallinity of the organic-inorganic perovskite compound include, for example, thermal annealing, irradiation with high-intensity light such as laser, and plasma irradiation.
  • the photoelectric conversion layer may further contain an organic semiconductor or an inorganic semiconductor in addition to the organic-inorganic perovskite compound, as long as the effect of the present invention is not impaired.
  • the organic semiconductor or the inorganic semiconductor may function as a hole transport layer or an electron transport layer.
  • Examples of the organic semiconductor include compounds having a thiophene skeleton such as poly(3-alkylthiophene).
  • Other examples include conductive polymers having a polyparaphenylenevinylene skeleton, a polyvinylcarbazole skeleton, a polyaniline skeleton, a polyacetylene skeleton, etc.
  • Further examples include compounds having a phthalocyanine skeleton, a naphthalocyanine skeleton, a pentacene skeleton, a porphyrin skeleton such as a benzoporphyrin skeleton, a spirobifluorene skeleton, etc., and carbon-containing materials such as carbon nanotubes, graphene, and fullerene, which may be surface-modified.
  • the inorganic semiconductor examples include titanium oxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, zinc sulfide, CuSCN, Cu2O , CuI , MoO3 , V2O5 , WO3 , MoS2 , MoSe2 , and Cu2S .
  • the photoelectric conversion layer contains the organic-inorganic perovskite compound and the organic semiconductor or inorganic semiconductor
  • it may be a laminate in which a thin-film organic semiconductor or inorganic semiconductor portion is laminated with a thin-film organic-inorganic perovskite compound portion, or it may be a composite film in which an organic semiconductor or inorganic semiconductor portion is composited with an organic-inorganic perovskite compound portion.
  • a laminate is preferred in that it can be manufactured easily, and a composite film is preferred in that it can improve the charge separation efficiency in the organic semiconductor or inorganic semiconductor.
  • the thickness of the photoelectric conversion layer has a preferred lower limit of 5 nm and a preferred upper limit of 5000 nm. If the thickness is 5 nm or more, light can be sufficiently absorbed, resulting in high photoelectric conversion efficiency. If the thickness is 5000 nm or less, the occurrence of regions where charge separation is not possible can be suppressed, leading to improved photoelectric conversion efficiency.
  • a more preferred lower limit of the thickness is 10 nm, a more preferred upper limit is 1000 nm, an even more preferred lower limit is 20 nm, and an even more preferred upper limit is 500 nm.
  • the preferred lower limit of the thickness of the composite film is 30 nm, and the preferred upper limit is 3000 nm. If the thickness is 30 nm or more, sufficient light absorption is achieved, and the photoelectric conversion efficiency is high. If the thickness is 3000 nm or less, charges can easily reach the electrode, and the photoelectric conversion efficiency is high.
  • a more preferred lower limit of the thickness is 40 nm, and a more preferred upper limit is 2000 nm, and an even more preferred lower limit is 50 nm, and an even more preferred upper limit is 1000 nm.
  • the method for forming the photoelectric conversion layer is not particularly limited, and examples thereof include vacuum deposition, sputtering, chemical vapor deposition (CVD), electrochemical deposition, and printing.
  • a printing method by employing a printing method, a solar cell capable of exhibiting high photoelectric conversion efficiency can be easily formed over a large area. Examples of printing methods include spin coating and casting, and examples of methods using printing include roll-to-roll methods.
  • the power generating section may have an electron transport layer between the electrode serving as a cathode or the counter electrode and the photoelectric conversion layer.
  • the material for the electron transport layer is not particularly limited, and examples thereof include N-type conductive polymers, N-type low-molecular-weight organic semiconductors, N-type metal oxides, N-type metal sulfides, alkali metal halides, alkali metals, surfactants, and the like.
  • Specific examples thereof include cyano group-containing polyphenylene vinylene, boron-containing polymers, bathocuproine, bathophenanthrene, hydroxyquinolinatoaluminum, oxadiazole compounds, benzimidazole compounds, naphthalenetetracarboxylic acid compounds, perylene derivatives, phosphine oxide compounds, phosphine sulfide compounds, fluoro group-containing phthalocyanines, titanium oxide, zinc oxide, indium oxide, tin oxide, gallium oxide, tin sulfide, indium sulfide, zinc sulfide, and the like.
  • the electron transport layer may consist of only a thin-film electron transport layer, but preferably includes a porous electron transport layer.
  • the photoelectric conversion layer is a composite film in which an organic semiconductor or inorganic semiconductor portion is combined with an organic-inorganic perovskite compound portion, a more complex composite film (a more intricately intricate structure) is obtained, and the photoelectric conversion efficiency is increased. Therefore, it is preferable that the composite film is formed on the porous electron transport layer.
  • the thickness of the electron transport layer is preferably 1 nm at the lower limit and 2000 nm at the upper limit. If the thickness is 1 nm or more, holes can be blocked sufficiently. If the thickness is 2000 nm or less, resistance during electron transport is unlikely to occur, and photoelectric conversion efficiency is high.
  • a more preferred lower limit of the thickness of the electron transport layer is 3 nm, a more preferred upper limit is 1000 nm, an even more preferred lower limit is 5 nm, and an even more preferred upper limit is 500 nm.
  • the power generating section may have a hole transport layer between the electrode serving as an anode or the counter electrode and the photoelectric conversion layer.
  • the material of the hole transport layer is not particularly limited, and the hole transport layer may be made of an organic material.
  • the material of the hole transport layer include P-type conductive polymers, P-type low molecular weight organic semiconductors, P-type metal oxides, P-type metal sulfides, surfactants, and the like.
  • Specific examples of the material include compounds having a thiophene skeleton such as poly(3-alkylthiophene).
  • Examples of the material include conductive polymers having a triphenylamine skeleton, a polyparaphenylenevinylene skeleton, a polyvinylcarbazole skeleton, a polyaniline skeleton, a polyacetylene skeleton, and the like.
  • Examples of the material include compounds having a porphyrin skeleton such as a phthalocyanine skeleton, a naphthalocyanine skeleton, a pentacene skeleton, a benzoporphyrin skeleton, a spirobifluorene skeleton, and the like, molybdenum sulfide, tungsten sulfide, copper sulfide, tin sulfide, and the like, fluoro group-containing phosphonic acid, carbonyl group-containing phosphonic acid, and copper compounds such as CuSCN and CuI.
  • a porphyrin skeleton such as a phthalocyanine skeleton, a naphthalocyanine skeleton, a pentacene skeleton, a benzoporphyrin skeleton, a spirobifluorene skeleton, and the like
  • molybdenum sulfide tungsten sul
  • the flexible solar cell of the present invention has a flame-retardant layer.
  • a flame-retardant layer By providing a flame-retardant layer on a flexible solar cell, it is possible to suppress burning beyond the flame-retardant layer, and therefore to increase the flame retardancy in the thickness direction.
  • the flame-retardant layer may be one layer, or a plurality of flame-retardant layers may be provided.
  • the flame-retardant layer may be provided below the power generation unit, above the power generation unit, or both.
  • the flame-retardant layer When the flame-retardant layer is arranged above the power generation unit, the flame-retardant layer is required to have high transparency from the viewpoint of photoelectric conversion efficiency, but the material volume per unit area described below is easily satisfied, and the design freedom of the flexible solar cell as a whole can be increased.
  • the flame-retardant layer is arranged below the power generation unit, design constraints arise in order to satisfy the material volume per unit area described below, compared to when the flame-retardant layer is arranged above the power generation unit, while transparency is not required for the flame-retardant layer, and the range of material selection is expanded.
  • flame retardant means that the flame retardancy in the UL94 combustion test described later is VTM-0, VTM-1 or flame retardancy exceeding VTM-0.
  • the material of the flame-retardant layer is not particularly limited as long as it has flexibility and flame retardancy, and examples thereof include organic resins, inorganic materials, inorganic fibers, and composite reinforced materials consisting of inorganic fibers and organic resins.
  • organic resins include polycarbonate, polyphenylene sulfide, polyamide, polyvinyl chloride, polyimide, polypropylene, tetrafluoroethylene resin, perfluoroalkoxyalkane, polyvinylidene fluoride, polyacetal, polyetherimide, polyphenylsulfone, polyamideimide, polyetheretherketone, phenolic resin, urea resin, melamine resin, and polychlorotrifluoroethylene.
  • the inorganic materials include metal foil, punched metal, metal steel plate, and inorganic porous bodies.
  • the inorganic fibers include glass cloth, silica cloth, aluminum glass cloth, heat-resistant rock wool, alkaline earth silicate fiber, alumina cloth, carbon fiber, and organic-inorganic hybrid fiber.
  • the flame-retardant layer is preferably a composite reinforcement material having inorganic fibers and an organic material, since it has high strength and flame retardancy and is transparent, and is more preferably made of a composite reinforcement material having glass cloth and an organic resin.
  • the refractive index ratio of the glass cloth to the organic resin (refractive index of glass cloth/refractive index of organic resin) be 0.95 or more and 1.05 or less.
  • the refractive index ratio of the glass cloth to the organic resin is within the above range, the transparency of the flame-retardant layer is further increased, so that even when the flame-retardant layer is provided on the power generation section, the decrease in the photoelectric conversion efficiency can be further suppressed.
  • the refractive index ratio of the glass cloth to the organic resin is more preferably 0.97 or more and more preferably 1.03 or less.
  • the flame-retardant layer preferably contains a coupling material.
  • the flame-retardant layer contains a coupling material, which makes it easier for the resin constituting the sealing layer to be impregnated into the flame-retardant layer, and makes it difficult for bubbles to occur in the flame-retardant layer. Therefore, when a transparent material is used for the flame-retardant layer, the transparency of the flame-retardant layer can be increased. Even if a transparent material is not used, the adhesion between the flame-retardant layer and the sealing layer is increased, and interlayer peeling can be further suppressed.
  • Examples of the coupling material include acrylic silane, amino silane, epoxy silane, mercapto silane, vinyl silane, methacryl silane, ureido silane, alkyl silane, styryl silane, isocyanurate silane, isocyanate silane, acid anhydride silane, and water-based acrylic emulsion.
  • the coupling material is preferably hydrophobic.
  • the present inventors have found that in a flexible solar cell using an organic/inorganic perovskite compound in the photoelectric conversion layer, if a hydrophilic material is used as the coupling material, the photoelectric conversion layer is deteriorated during sealing. Therefore, in the case of a flexible solar cell using an organic/inorganic perovskite compound, the deterioration of the photoelectric conversion layer can be suppressed by using a hydrophobic coupling material among the above coupling materials.
  • hydrophobic coupling materials examples include acrylic silane, amino silane, epoxy silane, mercapto silane, vinyl silane, methacryl silane, ureido silane, alkyl silane, styryl silane, isocyanurate silane, isocyanate silane, and acid anhydride silane.
  • the content of the coupling material is not particularly limited, but from the viewpoint of further increasing the transparency of the flame-retardant layer and suppressing delamination, it is preferably 0.1% by weight or more relative to 100% by weight of the flame-retardant layer, more preferably 1% by weight or more, and more preferably 10% by weight or less, and more preferably 3% by weight or less.
  • the flame-retardant layer may be disposed as the outermost layer on the bottom side (lower side).
  • an additional function can be imparted by disposing the flame-retardant layer on the outermost layer on the bottom side (lower side).
  • the flame-retardant layer is a composite reinforcement material having inorganic fibers and organic materials with excellent mechanical strength, it can also be used to fix flexible solar cells.
  • the installation surface of the flexible solar cell is prone to puddles and takes a long time to dry because it is not exposed to the sun, so moisture is likely to penetrate from the bottom side of the flexible solar cell. Therefore, by disposing a glass film with excellent water vapor barrier performance as a flame-retardant layer on the outermost layer on the bottom side, it is possible to effectively suppress the penetration of water vapor from the outside.
  • the flame retardant layer preferably has a flame retardancy of VTM-0 or higher in the UL94 flame test.
  • the UL94 flammability test is a standard for judging the flammability of materials, and evaluates the flame retardancy of materials with grades of VTM-0 to VTM-2. VTM-0 is the most flame retardant grade, and if the result of the UL94 flammability test on the flame retardant layer is VTM-0, the flame retardancy can be further improved.
  • Examples of materials that satisfy the flame retardancy of VTM-0 or higher include flame retardant PET, glass cloth, glass film, silica cloth, aluminum glass cloth, aluminum foil, metal mesh, and composite reinforced materials made of inorganic fibers and organic resins.
  • the UL94 flammability test is measured by the following method.
  • test specimen 200 ⁇ 5 ⁇ 50 ⁇ 1 ⁇ 0.5 mm.
  • Roll the resulting test specimen into a cylinder with the long sides facing the sides (200 mm high) and attach it vertically to the clamp.
  • apply a 20 mm flame to the bottom end of the test specimen for 3 seconds.
  • the above test is carried out five times, and the flammability (flame retardancy) is judged based on the criteria in Table 1 below.
  • the glowing time in the table refers to the time the specimen burns like a charcoal fire after ignition. The burning time does not include the time it is in contact with the flame.
  • the flame retardancy of the flame retardant layer is VTM-0 or higher, particularly when the flame retardant layer is a composite reinforcing material having flame retardant PET, a glass film, a glass cloth, and an organic resin, the flame retardancy of the resulting flexible solar cell is enhanced, and therefore, as long as the thickness of the flame retardant layer is 75 ⁇ m or more, excellent flame retardancy in the planar direction can be exhibited regardless of the amount of flammable components laminated on the flame retardant layer described below.
  • the present invention also provides a flexible solar cell having a power generation section and a flame-retardant layer, wherein the flame-retardant layer is a composite reinforcing material having glass cloth and an organic resin, and the thickness of the flame-retardant layer is 75 ⁇ m or more.
  • Other configurations of the power generation section, flame retardant layer, sealing layer, front sheet, back sheet and the like in the present invention are similar to those of the power generation section, flame retardant layer, sealing layer, front sheet and back sheet described above or below.
  • the flame-retardant layer has a thickness of 75 ⁇ m or more.
  • the thickness of the flame-retardant layer is preferably 100 ⁇ m or more, more preferably 150 ⁇ m or more, and is preferably 500 ⁇ m or less, more preferably 300 ⁇ m or less, and even more preferably 200 ⁇ m or less.
  • the flexible solar cell of the present invention may have a front sheet on top.
  • the front sheet has a role of suppressing light reflection and improving the drainage performance of the surface of the flexible solar cell by forming a pattern such as unevenness or an arc on the surface.
  • a pattern such as unevenness or an arc on the surface.
  • a front sheet having a convex arc with an apex at the center of the flexible solar cell is provided, a drainage gradient can be provided from the center to the edge of the solar cell, and if a front sheet having a concave arc with a lowest point at the center of the flexible solar cell is provided, a water collection section can be provided from the edge of the solar cell to the center.
  • the design can be improved by forming random unevenness on the front sheet.
  • the material of the front sheet is not particularly limited as long as it has transparency, and examples thereof include fluorine-containing resins, vinyl chloride resins, polyethylene resins, polycarbonate resins, etc. Specific examples include polycarbonate, polyvinyl chloride, tetrafluoroethylene resin, polyvinylidene fluoride, polychlorotrifluoroethylene, etc. Among these, fluorine-containing resins are preferred because of their excellent weather resistance.
  • the thickness of the front sheet is not particularly limited, but is preferably 25 ⁇ m or more, more preferably 50 ⁇ m or more, and more preferably 1000 ⁇ m or less, and more preferably 300 ⁇ m or less, from the viewpoint of the balance between light transmittance and the functionality of the front sheet. Note that if the material of the front sheet is flame retardant and has a thickness of 50 ⁇ m or more, the front sheet is also treated as a flame retardant layer in this specification.
  • the flexible solar cell of the present invention preferably has an encapsulation layer.
  • a sealing layer By wrapping the power generating section with a sealing layer, it is possible to suppress deterioration of the power generating section due to components in the atmosphere.
  • the material for the sealing layer include thermosetting resins, thermoplastic resins, and inorganic materials.
  • the thermosetting resins and thermoplastic resins include epoxy resins, acrylic resins, silicone resins, phenolic resins, melamine resins, and urea resins.
  • butyl rubber examples include butyl rubber, polyester, polyurethane, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl alcohol, polyvinyl acetate, ABS resin, polybutadiene, polyamide, polycarbonate, polyimide, and polyisobutylene.
  • the thickness of the sealing layer is preferably 10 ⁇ m or more, more preferably 50 ⁇ m or more, and is preferably 1000 ⁇ m or less, and more preferably 700 ⁇ m or less, from the viewpoint of balancing the protective performance and flexibility of the power generation unit. If the sealing does not have flame retardancy and the flame retardant layer is located below the sealing layer, the thickness of the sealing layer is adjusted to satisfy the material volume per unit area described below.
  • the flexible solar cell of the present invention may have a backsheet at the bottom.
  • the back sheet has a role of preventing the intrusion of substances such as moisture that cannot be prevented by the sealing layer alone, thereby enhancing the weather resistance of the flexible solar cell.
  • Examples of the material for the back sheet include polyethylene terephthalate.
  • the thickness of the back sheet is not particularly limited, but from the viewpoint of the balance between flexibility and functionality of the back sheet, it is preferably 50 ⁇ m or more, more preferably 100 ⁇ m or more, and preferably 1000 ⁇ m or less, more preferably 500 ⁇ m or less.
  • the layer having a flame retardancy lower than VTM-2 in the UL94 flame test has a material volume per unit area of 0.075 cm 3 /cm 2 or less.
  • the layer with a flame retardancy lower than VTM-2 in the UL94 flame test i.e., the layer of a flammable component, has a material volume per unit area in the above range, so that the layer can exhibit excellent flame retardancy by suppressing large-scale fire spread in the planar direction that occurs when the flexible solar cell is made large in area.
  • the material volume per unit area is preferably 0.075 cm3 /cm2 or less , and more preferably 0.05 cm3 /cm2 or less .
  • the lower limit of the material deposition per unit area is preferably 0.001 cm3 / cm2 or more, and more preferably 0.002 cm3 / cm2 or more.
  • the material volume per unit area can be calculated by cutting the flexible solar cell up to the measurement position with a microtome (HistoCore AUTOCUT R, manufactured by Leica Microsystems or an equivalent product), enlarging the cross section with an SEM (SU3800, manufactured by Hitachi High-Technologies Corporation or an equivalent product), and measuring the thickness of a layer that is less flame-retardant than VTM-2.
  • a microtome HaistoCore AUTOCUT R, manufactured by Leica Microsystems or an equivalent product
  • SEM SU3800, manufactured by Hitachi High-Technologies Corporation or an equivalent product
  • flame retardancy lower than VTM-2 means that the flame retardancy is VTM-2 or lower than VTM-2, that is, the flame retardancy does not meet VTM-0 or VTM-1. Therefore, layers with flame retardancy higher than VTM-0, VTM-0 and VTM-1 are excluded from the calculation of the unit area material volume even if they are arranged on the flame retardant layer.
  • the unit area material volume is measured at the part where the power generation part is formed. In addition, when the flexible solar cell has unevenness, the unit area material volume is measured so as to include the thickest part among the parts where the power generation part is formed. Furthermore, when multiple flame retardant layers are formed, the unit area material volume on the flame retardant layer located at the top (light incidence side) is measured.
  • the power generation part other than the substrate is excluded. The parts of the power generation part other than the substrate are much thinner than the other layers, so even if it contains a layer with lower flame retardancy than VTM-2, the effect on combustion is small enough to be within the margin of error.
  • the layer having a flame retardancy lower than VTM-2 in the UL94 flame test among the layers disposed on the flame retardant layer, has a thickness of 750 ⁇ m or less.
  • the thickness of the layer less flame-retardant than VTM-2 is within the above range, thereby enabling the flame retardancy in the planar direction to be further increased.
  • the thickness of the layer less flame-retardant than VTM-2 is preferably 700 ⁇ m or less, and more preferably 200 ⁇ m or less.
  • the remaining rate of the flame-retardant layer in a flame propagation test carried out according to the IEC 61730-2 MST23 standard is preferably 30% by weight or more.
  • the remaining rate of the flame retardant layer in the flame spread test performed according to the IEC 61730-2 MST23 standard is within the above range, the flame retardancy in the planar direction can be further improved.
  • the remaining rate of the flame retardant layer in the flame spread test is more preferably 50% by weight or more, and even more preferably 80% by weight or more.
  • the upper limit of the remaining rate of the flame retardant layer in the flame spread test is not particularly limited, and the higher the better, but it is usually 100% by weight or less.
  • FIG. 1(a) to (c) schematic diagrams showing an example of the structure of the flexible solar cell of the present invention are shown in Figures 1(a) to (c).
  • a power generation section 4 having an electrode 41, a photoelectric conversion layer 42, a counter electrode 43, and a substrate 44 is laminated on a back sheet 1.
  • the power generation section 4 is sealed with a sealing layer 5 to prevent the intrusion of atmospheric components, etc., and a flame-retardant layer 3 is laminated on the sealing layer 5, and a front sheet 6 is laminated on the flame-retardant layer 3 via an adhesive layer 2.
  • the flame-retardant layer 3 is also formed below the power generation section 4, and in the flexible solar cell of Figure 1(c), the flame-retardant layer 3 is formed only below the power generation section 4. Note that in the flexible solar cells of Figures 1(a) to (c), there are frame sections at both ends where the power generation section 4 is not formed and where the unit area material volume is larger than the other sections.
  • the frame portion where the power generating unit 4 is not formed is only a small portion of the entire flexible solar cell unit, and the frame portion of the flexible solar cell unit is often covered with a fixing member, so even if the material volume per unit area in the frame portion where the power generating unit is not formed is outside the above range, it does not affect the flame retardancy in the planar direction.
  • the present invention provides a flexible solar cell with excellent flame retardancy in the horizontal direction by making the flame retardant layer have a certain thickness or more and setting the material volume per unit area of the layer having a flame retardancy lower than VTM-2 among the layers formed on the flame retardant layer within the above range.
  • the flame retardancy of the flame retardant layer is high and the thickness of the layer having a flame retardancy lower than VTM-2 is within a specific range, a flexible solar cell with excellent flame retardancy in the horizontal direction can be provided.
  • the present invention also provides a flexible solar cell having such a power generation section and a flame-retardant layer, wherein the flame-retardant layer has a thickness of 75 ⁇ m or more and a flame retardancy of VTM-0 or higher in the UL94 flame test, and a layer disposed on the flame-retardant layer that has a flame retardancy lower than VTM-2 in the UL94 flame test has a thickness of 750 ⁇ m or less.
  • Other configurations of the power generation section, flame retardant layer, sealing layer, front sheet, back sheet, etc. in the present invention are similar to those of the power generation section, flame retardant layer, sealing layer, front sheet, and back sheet described above.
  • the method for producing the solar cell of the present invention is not particularly limited.
  • the electrode, the photoelectric conversion layer, the counter electrode, etc. are first laminated on the substrate by a printing method to produce a power generation unit.
  • a sheet is prepared on the back sheet on which an adhesive layer, a flame-retardant layer, a sealing layer, etc. are laminated according to the design of the flexible solar cell, and a sheet is prepared on the front sheet on which an adhesive layer, a flame-retardant layer, a sealing layer, etc. are laminated according to the design, and the obtained power generation unit is sandwiched between these sheets and laminated to produce the solar cell.
  • the flexible solar cell of the present invention has excellent flame retardancy in the planar direction, and therefore the larger the area of the flexible solar cell unit, the greater the effect. Specifically, the effect of the present invention is more pronounced when the size of the flexible solar cell is 1 m or more in width and 1 m or more in length. In order to more effectively exhibit the effect of the present invention, the size of the flexible solar cell of the present invention is preferably 1 m or more in width and/or length, more preferably 2 m or more, and even more preferably 4 m or more. There is no particular upper limit on the size of the flexible solar cell of the present invention, but due to manufacturing technology, the width is limited to about 10 m. Note that when manufacturing by a printing method, there is no particular upper limit on the length since it can be manufactured continuously.
  • the band-shaped flexible solar cell units of the present invention are side by side so that the long sides are in the oblique direction.
  • the gaps between each unit are formed in the oblique direction, making it easier for dirt to be washed away by rain, etc., and thus dirt can be further suppressed.
  • the gap between each unit is preferably 1 mm or more, preferably 2000 mm or less, more preferably 500 mm or less, and even more preferably 10 mm or less.
  • the present invention makes it possible to provide a solar cell that has excellent flame retardancy in the planar direction.
  • FIG. 1 is a schematic diagram showing an example of the structure of a flexible solar cell of the present invention.
  • Example 1 Manufacturing of a flexible solar cell A PET film having a thickness of 100 ⁇ m was prepared as a substrate. An ITO film having a thickness of 200 nm was formed as a counter electrode on the substrate by sputtering. A thin-film electron transport layer having a thickness of 20 nm was formed on the formed counter electrode by sputtering. Furthermore, a titanium oxide paste containing titanium oxide was applied on the thin-film electron transport layer by a spin coating method, and then dried to form a porous electron transport layer having a thickness of 100 nm.
  • lead iodide was dissolved as a metal halide compound in a mixed solvent of N,N-dimethylformamide (DMF) and dimethyl sulfoxide (DMSO) to prepare a 1M solution, and a film was formed on the porous electron transport layer by a spin coating method. Furthermore, methylammonium iodide was dissolved as an amine compound in 2-propanol to prepare an 8 wt% solution. This solution was applied onto the lead iodide by spin coating, and annealed at 150°C for 10 minutes to form a photoelectric conversion layer containing CH 3 NH 3 PbI 3 , an organic-inorganic perovskite compound, having a thickness of 700 nm.
  • DMF N,N-dimethylformamide
  • DMSO dimethyl sulfoxide
  • a chlorobenzene solution containing 2% by weight of Spiro-OMETAD (manufactured by Merck) was applied onto the photoelectric conversion layer by spin coating, and then dried to form a hole transport layer having a thickness of 80 nm.
  • an Al film having a thickness of 100 nm was formed as an electrode on the photoelectric conversion layer by sputtering, and a power generation unit consisting of a substrate, a counter electrode, an electron transport layer, a photoelectric conversion layer, a hole transport layer, and an electrode was obtained.
  • a 50 ⁇ m thick PET sheet was prepared as the front sheet.
  • Sheet A was obtained by applying polyisobutylene to the front sheet as a sealing layer to a thickness of 12.5 ⁇ m.
  • an aluminum-containing back sheet manufactured by Toyo Aluminum Co., Ltd., FAPL
  • polyisobutylene (VTM-2) was applied to the aluminum-containing back sheet as an adhesive layer to a thickness of 50 ⁇ m.
  • Examples 2 to 17, 31 to 36, Comparative Examples 1 to 4 Flexible solar cells were obtained in the same manner as in Example 1, except that the configuration of each layer and the width of the flexible solar cell were as shown in Tables 2 to 5, and the material volume per unit area was calculated. Note that in Examples 33 to 36, the flame retardancy of the front sheet was VTM-0, so the front sheet was treated as the flame retardant layer. Details of the materials of the flame retardant layer B and the front sheet in the tables are as follows: Flame-retardant PET: FR321, Celanese silica cloth: NSC, Nippon Glass Fiber Industry Co., Ltd. aluminum glass cloth: aluminum glass cloth, San-ei Kogyo Co., Ltd.
  • Examples 18 to 30 A flexible solar cell was obtained in the same manner as in Example 1, except that the material of the flame-retardant layer B was surface-treated and 20% by weight of the coupling material shown in Tables 3 and 4 was attached to 100% by weight of the flame-retardant layer B, and the material volume per unit area was calculated. Details of the materials used for the surface treatment are as follows: Acrylic silane: KBM-5103, Shin-Etsu Chemical Co., Ltd. Amino silane: KBM-602, Shin-Etsu Chemical Co., Ltd. Epoxy silane: KBM-303, Shin-Etsu Chemical Co., Ltd. Mercapto silane: KBM-802, Shin-Etsu Chemical Co., Ltd.
  • Vinyl silane KBM-1003, Shin-Etsu Chemical Co., Ltd.
  • Methacrylic silane KBM-502, Shin-Etsu Chemical Co., Ltd.
  • Ureido silane KBE-585A, Shin-Etsu Chemical Co., Ltd.
  • Example 37 A power generating unit was obtained in the same manner as in Example 1. Next, a PET sheet with a thickness of 50 ⁇ m was prepared as a front sheet, and polyisobutylene was applied to the front sheet as an adhesive layer to a thickness of 50 ⁇ m. Next, a glass cloth-impregnated resin film with a thickness of 100 ⁇ m was laminated on the adhesive layer as a flame-retardant layer A, and polyisobutylene was applied to the glass cloth as a sealing layer to a thickness of 50 ⁇ m to obtain a sheet A. Next, a sheet B was produced in the same manner as in Example 1, except that the thickness of the polyisobutylene was 50 ⁇ m.
  • the power generating unit was sandwiched between the sheets A and B and laminated so that the sealing layer of the sheet A and the base material of the power generating unit faced each other, and the sealing layer of the sheet B and the electrode of the power generating unit faced each other, thereby obtaining a flexible solar cell with a width of 1000 mm and a length of 1000 mm having a structure as shown in FIG. 1(b) (referred to as structure (b) in the table).
  • structure (b) in the table) The material volume per unit area of the obtained flexible solar cell was calculated in the same manner as in Example 1.
  • Example 38 A power generating section was obtained in the same manner as in Example 1. Next, sheet A was produced in the same manner as in Example 37. Subsequently, polyisobutylene was applied as a sealing layer to a thickness of 50 ⁇ m on the same aluminum-containing back sheet as in Example 1 to obtain sheet B. Thereafter, sheet A, the power generating section, and sheet B were laminated in the same manner as in Example 1 to obtain a flexible solar cell having a width of 1000 mm and a length of 1000 mm and having a structure as shown in FIG. 1(a) (referred to as structure (a) in the table). For the obtained flexible solar cell, the material volume per unit area was calculated in the same manner as in Example 1.
  • the present invention makes it possible to provide a solar cell that has excellent flame retardancy in the planar direction.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Photovoltaic Devices (AREA)
PCT/JP2024/012557 2023-03-28 2024-03-28 フレキシブル太陽電池 Ceased WO2024204490A1 (ja)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2025511111A JPWO2024204490A1 (https=) 2023-03-28 2024-03-28

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2023-051001 2023-03-28
JP2023051001 2023-03-28

Publications (1)

Publication Number Publication Date
WO2024204490A1 true WO2024204490A1 (ja) 2024-10-03

Family

ID=92906713

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2024/012557 Ceased WO2024204490A1 (ja) 2023-03-28 2024-03-28 フレキシブル太陽電池

Country Status (2)

Country Link
JP (1) JPWO2024204490A1 (https=)
WO (1) WO2024204490A1 (https=)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2026004389A1 (ja) * 2024-06-25 2026-01-02 積水化学工業株式会社 フレキシブル太陽電池

Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102184989A (zh) * 2011-03-23 2011-09-14 浙江恒基光伏电力科技股份有限公司 一种防火晶体硅光伏组件
WO2012161134A1 (ja) * 2011-05-20 2012-11-29 旭化成ケミカルズ株式会社 難燃樹脂フィルム及びそれを用いた太陽電池バックシート
WO2012169591A1 (ja) * 2011-06-09 2012-12-13 住友精化株式会社 不燃フィルム、不燃フィルム用分散液、不燃フィルムの製造方法、太陽電池バックシート、フレキシブル基板、及び、太陽電池
JP2013039746A (ja) * 2011-08-17 2013-02-28 Fujifilm Corp ポリマーシート、太陽電池モジュール用バックシートおよび太陽電池モジュール
JP2013051395A (ja) * 2011-08-03 2013-03-14 Toyo Ink Sc Holdings Co Ltd 太陽電池裏面保護シートならびに太陽電池モジュール
JP2013191673A (ja) * 2012-03-13 2013-09-26 Fuji Electric Co Ltd フレキシブル太陽電池モジュール
JP2014038925A (ja) * 2012-08-15 2014-02-27 Mitsubishi Chemicals Corp 防炎太陽電池モジュール
JP2014193529A (ja) * 2013-03-28 2014-10-09 Sumitomo Seika Chem Co Ltd 放熱フィルム、熱放射層用分散液、放熱フィルムの製造方法、及び、太陽電池
JP2017209943A (ja) * 2016-05-27 2017-11-30 ユニチカ株式会社 透明シート
CN107722910A (zh) * 2017-09-12 2018-02-23 广东生益科技股份有限公司 一种光伏背板胶粘剂用树脂组合物及使用其的光伏背板

Patent Citations (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102184989A (zh) * 2011-03-23 2011-09-14 浙江恒基光伏电力科技股份有限公司 一种防火晶体硅光伏组件
WO2012161134A1 (ja) * 2011-05-20 2012-11-29 旭化成ケミカルズ株式会社 難燃樹脂フィルム及びそれを用いた太陽電池バックシート
WO2012169591A1 (ja) * 2011-06-09 2012-12-13 住友精化株式会社 不燃フィルム、不燃フィルム用分散液、不燃フィルムの製造方法、太陽電池バックシート、フレキシブル基板、及び、太陽電池
JP2013051395A (ja) * 2011-08-03 2013-03-14 Toyo Ink Sc Holdings Co Ltd 太陽電池裏面保護シートならびに太陽電池モジュール
JP2013039746A (ja) * 2011-08-17 2013-02-28 Fujifilm Corp ポリマーシート、太陽電池モジュール用バックシートおよび太陽電池モジュール
JP2013191673A (ja) * 2012-03-13 2013-09-26 Fuji Electric Co Ltd フレキシブル太陽電池モジュール
JP2014038925A (ja) * 2012-08-15 2014-02-27 Mitsubishi Chemicals Corp 防炎太陽電池モジュール
JP2014193529A (ja) * 2013-03-28 2014-10-09 Sumitomo Seika Chem Co Ltd 放熱フィルム、熱放射層用分散液、放熱フィルムの製造方法、及び、太陽電池
JP2017209943A (ja) * 2016-05-27 2017-11-30 ユニチカ株式会社 透明シート
CN107722910A (zh) * 2017-09-12 2018-02-23 广东生益科技股份有限公司 一种光伏背板胶粘剂用树脂组合物及使用其的光伏背板

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2026004389A1 (ja) * 2024-06-25 2026-01-02 積水化学工業株式会社 フレキシブル太陽電池

Also Published As

Publication number Publication date
JPWO2024204490A1 (https=) 2024-10-03

Similar Documents

Publication Publication Date Title
JP6138968B2 (ja) 太陽電池
CN113261126B (zh) 太阳能电池
US20160111223A1 (en) A laminated opto-electronic device and method for manufacturing the same
JP6286106B2 (ja) 太陽電池、及び、有機半導体用材料
WO2020208854A1 (ja) 太陽電池モジュール
US20190198256A1 (en) Solar cell
JP2022075784A (ja) 太陽電池及び太陽電池の製造方法
WO2013035283A1 (ja) 透明導電フィルム、その製造方法、フレキシブル有機電子デバイス、及び、有機薄膜太陽電池
WO2012033102A1 (ja) 透明導電フィルム、その製造方法、電子デバイス、及び、有機薄膜太陽電池
WO2024204490A1 (ja) フレキシブル太陽電池
JP2023060630A (ja) 光電変換素子及び太陽電池モジュール
JP2020053454A (ja) 太陽電池及び太陽電池の製造方法
JP6921582B2 (ja) 太陽電池
JP7679529B1 (ja) フレキシブル太陽電池
US20210288277A1 (en) Flexible solar cell
JP7811296B1 (ja) 太陽光発電装置
JP7755769B1 (ja) 太陽光発電装置
CN117337057A (zh) 钙钛矿太阳能电池及其制备方法
JP2026004217A (ja) フレキシブル太陽電池
JP2022152729A (ja) 太陽電池の製造方法及び太陽電池
WO2025173743A1 (ja) フレキシブル太陽電池
WO2026004389A1 (ja) フレキシブル太陽電池
JP2026058134A (ja) フレキシブル太陽電池
JP7833080B1 (ja) フレキシブル太陽電池の設置構造
WO2022009636A1 (ja) 太陽電池および光電変換素子

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 24780591

Country of ref document: EP

Kind code of ref document: A1

ENP Entry into the national phase

Ref document number: 2025511111

Country of ref document: JP

Kind code of ref document: A

WWE Wipo information: entry into national phase

Ref document number: 2025511111

Country of ref document: JP

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 24780591

Country of ref document: EP

Kind code of ref document: A1