Solar power generation equipment

Abstract

To provide a solar power generation device which is low in cost, has high moisture resistance, and can prevent cracking of thin glass even when bent. [Solution] A solar power generation device having a power generation section, which has multiple thin glass sheets at at least either the top or bottom of the power generation section, and which has overlapping portions when the solar power generation device is viewed in a plane from the top or bottom, and which is characterized in that the multiple thin glass sheets that make up the overlapping portions do not contact each other and have an elastic body at least partially between the multiple thin glass sheets at the overlapping portions.

Description

[Technical Field]

[0001] The present invention relates to a solar power generation device. [Background technology]

[0002] Conventionally, solar power generation devices have been actively developed that use laminates in which an N-type semiconductor layer and a P-type semiconductor layer are disposed between opposing electrodes, with inorganic semiconductors such as silicon being mainly used as the N-type and P-type semiconductors. However, such inorganic solar power generation devices have the problems of being costly to manufacture and difficult to enlarge, limiting the range of their use. Therefore, in recent years, perovskite solar cells have been attracting attention, which use organic-inorganic perovskite compounds with a perovskite structure using lead, tin, or the like as the central metal in the photoelectric conversion layer (for example, Patent Document 1, Non-Patent Document 1). Perovskite solar cells are expected to have high photoelectric conversion efficiency, and can be manufactured by a printing method, which allows for significant reductions in manufacturing costs.

[0003] On the other hand, in recent years, flexible solar power generation devices using heat-resistant polymer materials such as polyimide and polyester, or metal foil as a base material have been attracting attention. Flexible solar power generation devices have advantages such as ease of transportation and installation due to their thinness and light weight, and high impact resistance. For example, they are manufactured by laminating multiple layers, such as a photoelectric conversion layer that generates current when irradiated with light, in a thin film form on a flexible base material. Furthermore, if necessary, sealing sheets are laminated on the top and bottom surfaces of the solar power generation device to seal it. For example, 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. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-72327 [Patent Document 2] Japanese Patent Application Laid-Open No. 2013-253317 [Non-patent literature]

[0005] [Non-Patent Document 1] MMLee,et al,Science,2012,338,643 Summary of the Invention [Problem to be solved by the invention]

[0006] Such solar power generation devices require high water vapor barrier performance to ensure long-term stability. Conventional solar power generation devices use thin glass as the base material for the power generation unit to achieve both water vapor barrier properties and flexibility. Each layer of the power generation unit is sequentially laminated on the thin glass to protect the power generation unit from atmospheric moisture. Meanwhile, as solar power generation devices have become larger in recent years, the thin glass used has also become larger. However, large thin glass sheets are prone to cracking due to stress applied to a single point during handling, and once cracked, the crack spreads to the front surface of the glass, resulting in breakage. Therefore, the use of multiple thin glass sheets instead of large thin glass sheets has been considered, but this has the problem of moisture easily penetrating through the boundaries between the thin glass sheets. One possible solution to this problem is to position the boundaries of the thin glass sheets over non-power-generating areas between the power generation units, thereby increasing the distance to the power generation unit and preventing moisture from reaching the power generation unit, even if moisture does penetrate. However, in order to place the thin glass boundary between the power generation sections, it was necessary to prepare a thin glass of a specific size for each solar power generation device, which resulted in the problem of increased costs.Furthermore, when the solar power generation device is bent to be carried or installed, or when it is fixed in a bent state, the contact and interference between multiple thin glass sheets can cause the thin glass to crack.

[0007] The present invention aims to provide a photovoltaic power generation device that is low cost, has high moisture resistance, and can prevent cracking of thin glass sheets even when the thin glass sheets are bent. [Means for solving the problem]

[0008] The present invention includes the following Disclosures 1 to 7. The present invention will be described in detail below. [Disclosure 1] A solar power generation device having a power generation unit, a plurality of thin glass sheets at least in either the upper or lower part of the power generation section; the plurality of thin glass sheets have overlapping portions when the solar power generation device is viewed in plan from the top or bottom, The plurality of thin glass sheets constituting the overlapping portion do not contact each other, An elastic body is provided between at least a portion of the plurality of thin glass sheets in the overlapping portion. A solar power generation device characterized by the above. [Disclosure 2] The photovoltaic power generation device according to Disclosure 1, wherein the elastic body contains a sealing material. [Disclosure 3] The photovoltaic power generation device according to Disclosure 1 or 2, further comprising a sealing layer, wherein the plurality of thin glass sheets are entirely sealed with the elastic body and the sealing layer. [Disclosure 4] The photovoltaic power generation device according to Disclosure 3, wherein the power generation section is entirely sealed with the sealing layer. [Disclosure 5] a sealing layer seals the power generation unit and the surfaces of the plurality of thin glasses on the power generation unit side; 5. The photovoltaic power generation device according to any one of Disclosures 1 to 4, wherein a layer laminated on the surface of each of the plurality of thin glasses opposite to the power generation section is different from the sealing layer. [Disclosure 6] The photovoltaic power generation device according to Disclosure 1, wherein the elastic body has a modulus of transverse elasticity of 0.1 MPa or more and 100 MPa or less. [Disclosure 7] 7. The solar power generation device according to any one of Disclosures 1 to 6, wherein the photoelectric conversion layer of the power generation section contains an organic-inorganic perovskite compound. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a photovoltaic power generation device that is low cost, has high moisture resistance, and is capable of suppressing cracking of thin glass sheets even when the thin glass sheets are bent. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram illustrating an example of a solar power generation device according to the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in more detail below by giving specific embodiments, but the present invention is not limited to these embodiments.

[0012] (Embodiment 1) FIG. 1(a) is a schematic diagram illustrating an example of a solar power generation device of the present invention. The solar power generation device of the present invention shown in FIG. 1(a) has multiple thin glass sheets 2 at least above or below a power generation unit 1. The multiple thin glass sheets 2 have an overlapping portion 3 when viewed from the top or bottom of the solar power generation device. Arranging the thin glass sheets 2 above or below the power generation unit 1 enhances moisture resistance, and using multiple thin glass sheets 2 reduces breakage of the thin glass sheets during manufacturing compared to using a single large thin glass sheet. Furthermore, the overlapping portion 3, i.e., the overlapping edges of adjacent thin glass sheets 2, makes it difficult for moisture to penetrate through the boundaries between the thin glass sheets 2, even when multiple thin glass sheets 2 are used, thereby achieving high moisture resistance. Furthermore, the multiple thin glass sheets 2 that make up the overlapping portion 3 do not contact each other, and an elastic body 4 is disposed at least partially between the multiple thin glass sheets 2 in the overlapping portion 3. Because the multiple thin glass sheets 2 that make up the overlapping portion 3 do not come into contact with each other, it is possible to prevent cracks caused by contact between the thin glass sheets 2 when the solar power generation device is bent. In addition, the presence of an elastic body between the thin glass sheets 2 in the overlapping portion 3 reduces the stress applied to the thin glass sheets 2, further preventing cracks in the thin glass sheets 2. In addition, when a solar power generation device has multiple thin glass sheets above and below the power generation unit, the overlapping portion between the thin glass sheet arranged above the power generation unit and the thin glass sheet arranged below the power generation unit is not included in the overlapping portion in this specification. Furthermore, in this specification, "above" refers to the side from which light is incident when the solar power generation device is installed, and "below" refers to the opposite direction to "above", i.e., the direction toward the installation surface when the solar power generation device is installed.

[0013] As shown in FIG. 1(a), the solar power generation device of the present invention may be configured with an overlapping portion 3 on the power generation unit 1. When multiple thin glass sheets are used in conventional solar power generation devices, moisture easily penetrates through the boundaries between the thin glass sheets. If the boundaries are located on the power generation unit, moisture easily reaches the power generation unit, resulting in reduced moisture resistance. Therefore, to ensure moisture resistance, it was necessary to use thin glass sheets of a specific size so that all boundaries were located between the power generation units. In the solar power generation device of the present invention, the presence of the overlapping portion 3 makes it difficult for moisture to penetrate through the boundaries with the thin glass sheets 2, so that the solar power generation device can exhibit high moisture resistance even if the overlapping portion 3 is located on the power generation unit 1. As a result, there is no limit to the size of the thin glass sheets 2, allowing the use of less expensive, standardized thin glass sheets, thereby reducing costs. Furthermore, the solar power generation device of Figure 1(a) has, in addition to the power generation unit 1, the plurality of thin glass sheets 2, and the elastic body 4, another layer 8 that covers the entire power generation unit 1 and the plurality of thin glass sheets 2, a front sheet 6 that is placed at the top of the solar power generation device, and a back sheet 7 that is placed at the bottom of the solar power generation device.

[0014] 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 photoelectric conversion layer, and a counter electrode. In this specification, 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 gradually change. Elemental analysis of a 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 element distribution of a specific element. Furthermore, in this specification, the term "layer" refers not only to a flat thin-film layer but also to a layer that can form a complex, intricate structure together with other layers.

[0015] Examples of the substrate include resin films made of heat-resistant polymers such as polyimide and polyester, metal foils, thin glass sheets, etc. Among these, PET resin films are preferred from the viewpoints of cost and heat resistance.

[0016] The materials for the electrodes and counter electrodes are 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 / Al2O3 mixture, and Al / LiF mixture. Other examples include gold, silver, titanium, molybdenum, tantalum, tungsten, carbon, nickel, and chromium. These materials may be used alone or in combination.

[0017] The thickness of the electrode and the counter electrode is not particularly limited, but a preferred lower limit is 10 nm and a preferred upper limit is 1000 nm. If the thickness is 10 nm or more, the resistance can be reduced while the electrode functions. If the thickness is 1000 nm or less, the light transmittance can be further improved. A more preferred lower limit of the thickness of the electrode and the counter electrode is 50 nm and a more preferred upper limit is 500 nm.

[0018] The photoelectric conversion layer preferably contains an organic-inorganic perovskite compound. The organic-inorganic perovskite compound is a compound represented by the general formula AMX (where A is an organic base compound and / or an alkali metal, M is a lead or tin atom, and X is a halogen atom), and a solar cell containing such an organic-inorganic perovskite compound is also called an organic-inorganic hybrid solar cell. By using the organic-inorganic perovskite compound in the photoelectric conversion layer of the power generation section, the photoelectric conversion efficiency of the solar power generation device can be further improved.

[0019] The above A is an organic base compound and / or an alkali metal. Specific examples of 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.g., methylammonium (CHNH)), phenethylammonium, and the like. Of these, 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. Examples of the alkali metal include lithium, sodium, potassium, rubidium, and cesium.

[0020] The above M is a lead or tin atom. These metal atoms may be used alone or in combination of two or more.

[0021] The 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. By including a halogen in the structure, the organic-inorganic perovskite compound becomes soluble in organic solvents, enabling application to inexpensive printing methods and the like. In particular, X is preferably iodine, since this narrows the energy band gap of the organic-inorganic perovskite compound.

[0022] 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. Although the details are not clear, it is presumed that the above structure allows the orientation of the octahedra within the crystal lattice to be easily changed, thereby increasing the mobility of electrons in the organic-inorganic perovskite compound and improving the photoelectric conversion efficiency of solar cells.

[0023] The organic-inorganic perovskite compound is preferably a crystalline semiconductor. By crystalline semiconductor, we mean a semiconductor from which a scattering peak can be detected by measuring an X-ray scattering intensity distribution. When the organic-inorganic perovskite compound is a crystalline semiconductor, the mobility of electrons in the organic-inorganic perovskite compound increases, improving the photoelectric conversion efficiency of the solar power generation device.

[0024] The degree of crystallinity can also be evaluated as an index of crystallization by separating the scattering peaks derived from crystalline materials and the halo derived from amorphous parts detected by X-ray scattering intensity distribution measurement through fitting, determining the intensity integrals of each, and calculating the ratio of the crystalline part to the whole. The preferred lower limit of the crystallinity of the organic-inorganic perovskite compound is 30%. A crystallinity of 30% or more increases the electron mobility in the organic-inorganic perovskite compound, improving the photoelectric conversion efficiency of the solar cell. A more preferred lower limit of the crystallinity is 50%, and an 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.

[0025] The photoelectric conversion layer may further contain an organic or inorganic semiconductor in addition to the organic-inorganic perovskite compound, as long as the effects of the present invention are not impaired. The organic or 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 polyparaphenylene vinylene skeleton, a polyvinyl carbazole skeleton, a polyaniline skeleton, a polyacetylene skeleton, etc. Further examples include compounds having a porphyrin skeleton such as a phthalocyanine skeleton, a naphthalocyanine skeleton, a pentacene skeleton, or a benzoporphyrin skeleton, a spirobifluorene skeleton, etc. Also included are carbon-containing materials such as carbon nanotubes, graphene, and fullerenes, which may be surface-modified.

[0026] Examples of the inorganic semiconductor 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.

[0027] When 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 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 produced easily, and a composite film is preferred in that it can improve the charge separation efficiency in the organic semiconductor or inorganic semiconductor.

[0028] The thickness of the thin-film organic-inorganic perovskite compound portion is preferably 5 nm at the lower limit and 5000 nm at the upper limit. If the thickness is 5 nm or more, sufficient light absorption is possible, 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. The lower limit of the thickness is more preferably 10 nm, the upper limit is more preferably 1000 nm, the lower limit is even more preferably 20 nm, and the upper limit is even more preferably 500 nm.

[0029] When 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, 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, resulting in high photoelectric conversion efficiency. If the thickness is 3000 nm or less, charges can more easily reach the electrode, resulting in high photoelectric conversion efficiency. A more preferred lower limit of the thickness is 40 nm, and a more preferred upper limit is 2000 nm, with an even more preferred lower limit being 50 nm and an even more preferred upper limit being 1000 nm.

[0030] 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. Among these, the use of printing allows for the easy formation of large-area solar cells that can exhibit high photoelectric conversion efficiency. Examples of printing methods include spin coating and casting, and examples of methods using printing include roll-to-roll methods.

[0031] The power generating section may have an electron transport layer between the cathode electrode 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, and zinc sulfide.

[0032] The electron transport layer may consist of only a thin-film electron transport layer, but preferably includes a porous electron transport layer. In particular, when the photoelectric conversion layer is a composite film obtained by combining an organic semiconductor or inorganic semiconductor portion with an organic-inorganic perovskite compound portion, it is preferable that the composite film be formed on a porous electron transport layer, since a more complex composite film (more intricately intricate structure) can be obtained and the photoelectric conversion efficiency can be increased.

[0033] The thickness of the electron transport layer is preferably 1 nm at the lower limit and 2000 nm at the upper limit. A thickness of 1 nm or more ensures sufficient hole blocking. A thickness of 2000 nm or less reduces resistance during electron transport, resulting in high photoelectric conversion efficiency. The electron transport layer more preferably has a lower limit of 3 nm and a higher limit of 1000 nm, an even more preferred lower limit of 5 nm, and an even more preferred upper limit of 500 nm.

[0034] The power generating section may have a hole transport layer between the electrode serving as the anode / cathode 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. Examples of materials for the hole transport layer include p-type conductive polymers, p-type small-molecular-weight organic semiconductors, p-type metal oxides, p-type metal sulfides, and surfactants. Specific examples include compounds having a thiophene skeleton, such as poly(3-alkylthiophene). Other examples include conductive polymers having a triphenylamine skeleton, polyparaphenylenevinylene skeleton, polyvinylcarbazole skeleton, polyaniline skeleton, and polyacetylene skeleton. Further examples include compounds having a porphyrin skeleton, such as a phthalocyanine skeleton, a naphthalocyanine skeleton, a pentacene skeleton, or a benzoporphyrin skeleton; a spirobifluorene skeleton; molybdenum sulfide, tungsten sulfide, copper sulfide, tin sulfide, fluoro-group-containing phosphonic acid, carbonyl-group-containing phosphonic acid; and copper compounds, such as CuSCN and CuI.

[0035] Examples of glass constituting the thin glass sheet include soda glass, lead glass, borosilicate glass, alkali-free glass, etc. Among these, alkali-free glass is preferred because it can be used to form thinner thin glass sheets.

[0036] From the viewpoints of breakage resistance and ease of availability (cost), the size of the above-mentioned thin glass is preferably 20% or more of the area of ​​the power generation section, more preferably 30% or more, and even more preferably 50% or more, and preferably less than 90%, more preferably less than 80%, and even more preferably less than 70%. Furthermore, when the thin glass is rectangular, the specific size is preferably such that each side is 20 cm or more, more preferably 30 cm or more, and even more preferably 50 cm or more, and preferably 120 cm or less, more preferably 100 cm or less, even more preferably 90 cm or less, and even more preferably 80 cm or less.

[0037] From the viewpoint of the balance between flexibility and strength, the thickness of the above-mentioned thin glass is preferably 10 μm or more, more preferably 30 μm or more, and is preferably 1000 μm or less, more preferably 500 μm or less, and even more preferably 100 μm or less.

[0038] The width (length of the short side) of the overlapping portion is preferably 1 mm or more, more preferably 5 mm or more, even more preferably 10 mm or more, and even more preferably 15 mm or more, from the viewpoint of preventing the overlapping portion from disappearing due to manufacturing errors and further enhancing moisture resistance. There is no particular upper limit to the width of the overlapping portion, and the longer it is, the more difficult it is for moisture to reach the power generation portion and the higher the moisture resistance, but from the viewpoint of cost and light transmittance, it is preferably 200 mm or less, more preferably 100 mm or less, and even more preferably 50 mm or less.

[0039] The distance between the thin glass sheets at the overlapping portion is preferably 0.5 mm or more and 10 mm or less. By setting the distance between the thin glass sheets at the overlapping portion within the above range, it is possible to prevent the thin glass sheets from coming into contact with each other and cracking when the solar power generation device is bent while still exhibiting moisture-proofing properties. From the same viewpoint, the distance between the thin glass sheets at the overlapping portion is more preferably 1 mm or more, even more preferably 5 mm or more, more preferably 7 mm or less, and even more preferably 5 mm or less.

[0040] The thin glass sheet preferably has a slope at the overlapping portion. From the viewpoint of further enhancing moisture-wicking properties, the thin glass sheet is preferably as flat as possible. On the other hand, if the overlapping portion is inclined, the distance between the thin glass sheet and the power generation unit can be maintained constant, thereby providing stable moisture-wicking properties. Specifically, the inclination angle of the thin glass sheet at the overlapping portion (the angle between the plane of the solar power generation device and the thin glass sheet at the overlapping portion) is preferably 1° or more, more preferably 5° or more, and even more preferably 10° or more. When the inclination angle of the thin glass sheet at the overlapping portion is equal to or greater than the lower limit, the inclination of the overlapping portion can be achieved while maintaining the flatness of the entire thin glass sheet. Furthermore, the inclination angle of the thin glass sheet at the overlapping portion is preferably 45° or less, more preferably 30° or less, and even more preferably 25° or less. When the inclination angle of the thin glass sheet at the overlapping portion is equal to or less than the upper limit, the path to the power generation unit is longer, thereby better maintaining moisture-wicking properties of the overlapping portion. Since there is a difference in stress between the overlapping portion and other portions due to differences in the stacking state, such as the number of thin glass sheets stacked and the presence or absence of an elastic body, the overlapping portion naturally becomes inclined. The inclination angle can be adjusted by adjusting the strength of the thin glass sheet, the elastic modulus of the elastic body, and the like.

[0041] When the area of ​​the overlapping portion is taken as 100% when the solar power generation device is viewed in a plan view from the top or bottom, the elastic body is preferably arranged in 20% or more of the overlapping portion. When the arrangement ratio of the elastic body to the overlapping portion is within the above range, contact of the thin glass sheet can be more effectively suppressed. The arrangement ratio of the elastic body to the overlapping portion is more preferably 30% or more, even more preferably 70% or more, even more preferably 80% or more, and particularly preferably 100%.

[0042] When the longitudinal length of the overlapping portion is taken as 100% when the solar power generation device is viewed in a plan view from the top or bottom, the elastic body is preferably arranged to cover 20% or more of the longitudinal length of the overlapping portion. When the arrangement ratio of the elastic body to the longitudinal length of the overlapping portion is within the above range, contact of the thin glass sheets can be more effectively suppressed over the entire longitudinal direction. The arrangement ratio of the elastic body to the longitudinal length of the overlapping portion is more preferably 30% or more, even more preferably 70% or more, even more preferably 80% or more, and particularly preferably 100%.

[0043] The elastic body is not particularly limited as long as it can prevent the thin glass sheets from contacting each other, and examples thereof include thermosetting resins, thermoplastic resins, etc. Furthermore, the elastic body is not limited to a hard material, and may be a viscous resin material. In particular, it is preferable to use an elastic body with low water vapor permeability, since this further enhances moisture resistance, and it is more preferable that the elastic body contains a sealant.

[0044] Examples of the sealing material include thermosetting resins and thermoplastic resins. Examples of the thermosetting resins or thermoplastic resins include epoxy resins, acrylic resins, silicone resins, phenolic resins, melamine resins, and urea resins. Other examples include butyl rubber, polyester, polyurethane, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyvinyl alcohol, polyvinyl acetate, ABS resin, polybutadiene, polyamide, polycarbonate, polyimide, and polyisobutylene. From the viewpoint of further improving moisture-proofing performance, epoxy resins, EVA, and EVOH are preferred. When the photoelectric conversion layer contains an organic-inorganic perovskite compound, the resin material preferably has a solubility parameter (SP value) of 10 or less, since the organic components of the organic-inorganic perovskite compound are less likely to dissolve.

[0045] The elastic body preferably has a modulus of transverse elasticity of 0.1 MPa or more and 100 MPa or less. When the modulus of transverse elasticity of the elastic body is within the above range, the elastic body is elastically deformed when the solar power generation device is bent, thereby displacing the thin glass sheets, thereby reducing stress on the thin glass sheets. Furthermore, contact between the thin glass sheets can be suppressed, thereby suppressing cracking of the thin glass sheets. From the same viewpoint, the modulus of transverse elasticity of the elastic body is more preferably 0.5 MPa or more, even more preferably 1 MPa or more, more preferably 50 MPa or less, and even more preferably 10 MPa or less.

[0046] The elastic body preferably has a modulus of longitudinal elasticity of 100 Pa or more and 10,000 MPa or less. When the modulus of longitudinal elasticity of the elastic body is within the above range, contact between the thin glass sheets can be more effectively suppressed. From the same viewpoint, the longitudinal elastic modulus of the elastic body is more preferably 1000 MPa or more, even more preferably 2400 MPa or more, even more preferably 3000 MPa or more, more preferably 5000 MPa or less, even more preferably 4200 MPa or less, and even more preferably 4000 MPa or less.

[0047] The elastic body has a viscosity of 100 cP or more and 10 × 10 7 It is preferably equal to or less than cP. By having the viscosity of the elastic body within the above range, when the solar power generation device is bent, the elastic body is elastically deformed, which displaces the thin glass sheets, thereby reducing the stress acting on the thin glass sheets. Also, contact between the thin glass sheets can be suppressed, which can suppress cracking of the thin glass sheets. Furthermore, the handleability of the elastic body can be further improved. From the same viewpoint, the viscosity of the elastic body is more preferably greater than 800 cP, even more preferably 1500 cP or more, and more preferably 10 × 10 6 More preferably, 10 × 10 4 It is more preferably 0.1 cP or less.

[0048] The other layer is a layer that covers the power generating section and the thin glass sheet, and can be appropriately selected depending on the desired performance. For example, if the other layer is an adhesive layer, the adhesive strength between the front sheet and the back sheet can be further increased, and if the other layer is a flame-retardant layer, flame retardancy can be imparted. Conventional adhesives constituting the adhesive layer and flame retardants constituting the flame-retardant layer can be used without any particular limitation.

[0049] The solar power generation device of the present invention preferably has a sealing layer, and the plurality of thin glass sheets are entirely sealed with the elastic body and the sealing layer. By sealing the entire thin glass sheet with an elastic body and a sealing layer, it is possible to further improve the moisture-proofing property. The material of the sealing layer can be the same as the sealing material. In particular, when the elastic body is made of a sealing material and the material of the sealing layer is the same as the sealing material of the elastic body, that is, when the sealing layer and the elastic body are integrated, it is possible to further improve the moisture-proofing property. On the other hand, when the materials of the sealing layer and the elastic body are different, it is easier to adjust the hardness, viscosity, etc. of the elastomer, which makes it easier to suppress cracking of the thin glass sheet.

[0050] In the solar power generation device of the present invention, the entire power generation section is preferably sealed with the sealing layer. By enclosing the power generation unit in a sealing layer, deterioration of the power generation unit due to atmospheric components can be further suppressed. The sealing layer sealing the power generation unit can be the same as the sealing layer sealing the thin glass sheet. However, if the power generation unit uses an organic material for the photoelectric conversion layer, the sealing layer or materials in contact with the sealing layer may accelerate deterioration of the power generation unit. Therefore, it is preferable to use a sealing material that does not accelerate deterioration of the power generation unit. Examples of such sealing materials include silicone, polyisobutylene, polybutadiene, PMMA, etc. The sealing layer sealing the power generation unit may be the same as or different from the sealing layer sealing the thin glass sheet. In particular, when the elastic body, the sealing layer sealing the thin glass sheet, and the sealing layer sealing the power generation unit are made of the same sealing material and are integrated, the interface between the different materials is reduced, thereby further improving moisture resistance.

[0051] From the viewpoint of a balance between the protection performance of the power generation section and flexibility, the thickness of the sealing layer is preferably 10 μm or more, more preferably 50 μm or more, and is preferably 1000 μm or less, and more preferably 700 μm or less. Here, the thickness of the sealing layer refers to the maximum thickness in the portion consisting of only the sealing layer.

[0052] In the solar power generation device of the present invention, the power generation unit and the surfaces of the plurality of thin glass sheets facing the power generation unit are sealed by a sealing layer, and the layer laminated on the surfaces of the plurality of thin glass sheets opposite the power generation unit may be different from the sealing layer. The power generation unit and the space between the power generation unit and the thin glass sheet are sealed with a sealing layer, which further enhances moisture resistance. Furthermore, the material laminated on the surface of the thin glass sheet opposite the power generation unit, which is different from the sealing material, allows for greater design freedom. For example, if the layer laminated on the surface of the thin glass sheet opposite the power generation unit is an adhesive layer, a front sheet or back sheet can be placed even if the sealing material is made of a material with poor adhesive properties.

[0053] The solar power generation device of the present invention may have a front sheet on the outermost surface on the upper surface side. The front sheet is placed on the outermost surface of the upper surface of the solar power generation device, and by forming a pattern such as unevenness or an arc on the surface, it serves to suppress light reflection and improve the drainage performance of the surface of the solar power generation device. For example, by providing a front sheet with a convex arc with its peak at the center of the solar power generation device, a drainage gradient can be created from the center to the edge of the solar power generation device, and by providing a front sheet with a concave arc with its lowest point at the center of the solar power generation device, a water collection area can be created from the edge to the center of the solar power generation device. By providing such a drainage gradient or water collection area, the accumulation of dirt and other contaminants can be concentrated in a specific area. In addition, by forming random unevenness on the front sheet, the design can be improved.

[0054] The material of the front sheet is not particularly limited as long as it is transparent, 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.

[0055] The thickness of the front sheet is not particularly limited, but from the viewpoint of the balance between light transmittance and functionality of the front sheet, it is preferably 25 μm or more, more preferably 50 μm or more, and is preferably 1000 μm or less, more preferably 300 μm or less.

[0056] The solar power generation device of the present invention may have a back sheet on the outermost surface on the lower surface side. The back sheet has the role of preventing the penetration of substances that cannot be prevented by the sealing material alone, thereby enhancing the weather resistance of the photovoltaic power generation device. Examples of materials for the back sheet include polyethylene terephthalate.

[0057] 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 μm or more, more preferably 100 μm or more, and is preferably 1000 μm or less, more preferably 500 μm or less.

[0058] The method for manufacturing the solar power generation device of the present invention is not particularly limited. For example, in the case of the solar power generation device of Figure 1(a), other layers are laminated on a front sheet, and an elastic body and multiple thin glass sheets are arranged on the other layers so that overlapping portions are formed, and then other layers are laminated on the other layers to form Sheet A, and other layers are laminated on a back sheet to form Sheet B, and a power generation unit prepared by a conventional method is sandwiched between Sheet A and Sheet B and laminated.

[0059] When the power generating unit is composed of a substrate, an electrode, a photoelectric conversion layer, and a counter electrode, the power generating unit can be obtained by stacking the electrode on the substrate by sputtering, electron beam, or the like, applying a photoelectric conversion material onto the electrode and drying it to form a photoelectric conversion layer, and then stacking the counter electrode on the photoelectric conversion layer in the same manner as the electrode.

[0060] (Embodiment 2) 1(b) to 1(e) are schematic diagrams showing further embodiments of the solar power generation device of the present invention. The solar power generation device of Fig. 1(b) is the solar power generation device of Fig. 1(a) in which the other layer 8 and the elastic body 4 are integrated as a sealing layer 5. By integrating the other layer and the elastic body using the same material as the sealing layer, it is possible to further improve moisture resistance.

[0061] (Embodiment 3) 1(c), multiple thin glass sheets 2 are arranged at an angle to the plane of the solar power generation device. Even when the thin glass sheets 2 are arranged at an angle, the path that invading moisture takes to reach the power generation unit is longer, thereby providing high moisture-proofing properties.

[0062] (Embodiment 4) In the solar power generation device of FIG. 1(d), the power generation unit 1 and the surfaces of the plurality of thin glass sheets 2 facing the power generation unit 1 are sealed by a sealing layer 5, and the layer laminated on the surfaces of the plurality of thin glass sheets 2 opposite the power generation unit 1 is another layer 8, which is different from the sealing layer 5. Since the sealing layer 5 can exhibit sealing performance when laminated on the surface of the thin glass sheet 2 facing the power generation unit 1, further performance can be imparted by laminating another layer 8 on the surface opposite the thin glass sheet 2. Note that in the solar power generation device of FIG. 1(d), the elastic body 4 is a sealant and is integrated with the sealing layer 5.

[0063] (Embodiment 5) The solar power generation device of FIG. 1(e) has, in addition to the solar power generation device of FIG. 1(b), multiple thin glass sheets 2 also arranged below the power generation unit 1. By arranging the thin glass sheets 2 above and below the power generation unit 1, moisture resistance can be further improved. In this case, when the solar power generation device is viewed in plan from the top or bottom, it is preferable that the overlapping portion 3 of the thin glass sheets 2 arranged above the power generation unit 1 and the overlapping portion 3 of the thin glass sheets 2 arranged below the power generation unit 1 do not overlap in the thickness direction. By not aligning the overlapping portion 3 above the power generation unit 1 and the overlapping portion 3 below the power generation unit 1 in a straight line in the thickness direction, moisture penetration is more difficult, thereby further improving moisture resistance. Furthermore, because the overlapping portion 3 has relatively lower strength than other portions, arranging the overlapping portions 3 above and below the power generation unit 1 so that they do not overlap in the thickness direction can make the strength of the entire solar power generation device uniform. [Explanation of symbols]

[0064] 1 Power Generation Department 2 Thin glass 3 Overlapping parts 4 Elastic Body 5. Sealing layer 6 Front seats 7 Back Seat 8 Other Layers

Claims

1. A solar power generation device having a power generation unit, a plurality of thin glass sheets at least in either the upper or lower part of the power generation section; the plurality of thin glass sheets have overlapping portions with a width of 1 mm or more and 200 mm or less only at the ends of the plurality of thin glass sheets when the solar power generation device is viewed in plan from the top or bottom, The plurality of thin glass sheets constituting the overlapping portion do not contact each other, An elastic body is provided between at least a portion of the plurality of thin glass sheets in the overlapping portion. A solar power generation device characterized by the above.

2. 2. The solar power generation device according to claim 1, wherein the elastic body contains a sealing material.

3. 3. The solar power generation device according to claim 2, further comprising a sealing layer, wherein the plurality of thin glass sheets are entirely sealed with the elastic body and the sealing layer.

4. A solar power generation device as described in claim 3, characterized in that the sealing layer contains the sealing material.

5. 4. The solar power generation device according to claim 3, wherein the power generation section is entirely sealed with the sealing layer.

6. a sealing layer seals the power generation unit and the surfaces of the plurality of thin glasses on the power generation unit side; 2. The solar power generation device according to claim 1, wherein a layer laminated on a surface of each of the plurality of thin glasses opposite to the power generation section is different from the sealing layer.

7. 2. The solar power generation device according to claim 1, wherein the elastic body has a modulus of transverse elasticity of 0.1 MPa or more and 100 MPa or less.

8. 8. The solar power generation device according to claim 1, wherein the photoelectric conversion layer of the power generation section contains an organic-inorganic perovskite compound.

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