Laminated glass, vehicle, and method for producing laminated glass

Abstract

Provided are: laminated glass which suppresses deterioration of a solar battery cell and which excels in photovoltaic power generation output; and a method for producing the same. This laminated glass includes: a first glass plate; a second glass plate; a plurality of independent solar cells disposed between the first glass plate and the second glass plate and having different wavelengths at which external quantum efficiency is maximized; and an intermediate film. The intermediate film is disposed between at least the solar cells.

Description

Laminated glass, vehicle, and method for manufacturing laminated glass

[0001] This invention relates to laminated glass, a vehicle, and a method for manufacturing laminated glass.

[0002] In recent years, the idea of ​​encapsulating solar cells inside laminated glass has been explored. Patent Document 1 discloses a glass panel in which a solar cell element and a light-regulating element are sequentially arranged between a first glass plate on the sunlight incident side and a second glass plate on the sunlight transmission side, starting from the first glass plate side, and a heat-reflecting element is interposed between the solar cell element and the light-regulating element.

[0003] Separately, as a method to improve the power generation efficiency of solar cells, tandem solar cells, which stack multiple solar cells with different absorption ranges, are being considered. Patent document 2 discloses a multi-junction solar cell in which a transparent conductive film containing a layer of fine particles impregnated with a binder layer is arranged between the photoelectric conversion layers. A curable resin is used as the binder.

[0004] International Publication No. 2014 / 126065, Japanese Patent Publication No. 2010-80933

[0005] When encapsulating solar cells in laminated glass, stress was sometimes applied to the solar cells, causing cracks and other damage. This problem was particularly pronounced when encapsulating cells consisting of two or more stacked solar cells.

[0006] In view of the above issues, this disclosure provides laminated glass and a method for manufacturing the same that suppress the degradation of solar cells and have excellent output for solar power generation.

[0007] This disclosure includes the following embodiments: [1] Laminated glass comprising a first glass plate, a second glass plate, a plurality of independent solar cells with different wavelengths having the maximum external quantum efficiency, and an interlayer between the first glass plate and the second glass plate, wherein the interlayer is disposed between at least one solar cell. [2] The laminated glass according to [1], wherein the plurality of solar cells are arranged in order from the surface of incident sunlight to the wavelength having the maximum external quantum efficiency. [3] The wavelength (λ) of the solar cell closest to the surface of incident sunlight that has the maximum external quantum efficiency. ａ), and the difference (λ ｂ ), between the wavelength (λ ｂ −λ ａ ) at which the external quantum efficiency of the solar cell farthest from the sunlight incident surface is maximum, is 100 nm or more. The laminated glass according to [1] or [2]. [4] The value obtained by the following (Formula 1) is 0.3 or less. The laminated glass according to any one of [1] to [3]. S ａｂ / (S ａ +S ｂ −S ａｂ ) (Formula 1) However, S ａ represents the area of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell closest to the sunlight incident surface, and S ｂ represents the area of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell farthest from the sunlight incident surface, and S ａｂ represents the area of the overlapping portion of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell closest to the sunlight incident surface and the surface formed by the wavelength and the external quantum efficiency curve of the solar cell farthest from the sunlight incident surface. [5] The ratio (T ｉ ) of the thickness (T ｓ ) of the thickest solar cell among the solar cells to the thickness (T ｓ / T ｉ ) of the thickest intermediate film among the intermediate films disposed between the solar cells is 5 or less. The laminated glass according to any one of [1] to [4]. [6] The ratio (T ｉ ) of the thickness (T １ ) of the first glass to the thickness (T １ / T ｉ[1] to [2] A laminated glass according to any one of [1] to [2], wherein the ratio of the solar cells is 1 to 15. [7] A laminated glass according to any one of [1] to [2], wherein the plurality of solar cells are each independently selected from the group consisting of perovskite solar cells, silicon solar cells, compound solar cells, and organic thin-film solar cells. [8] A laminated glass according to any one of [1] to [2], wherein the plurality of solar cells are two solar cells, arranged from the sunlight incident surface side in the order of perovskite solar cell, silicon solar cell, perovskite solar cell, compound solar cell, perovskite solar cell, organic thin-film solar cell, compound solar cell, silicon solar cell, or perovskite solar cell, perovskite solar cell. [9] A laminated glass according to any one of [1] to [2], wherein the visible light transmittance of the interlayer arranged on the sunlight incident side of the solar cells is 85% or more.

[10] A laminated glass according to any one of [1] to [2], wherein the interlayer comprises a thermoplastic resin.

[11] A vehicle equipped with laminated glass according to any one of [1] to

[10] .

[12] A method for manufacturing laminated glass according to any one of [1] to

[10] , comprising arranging a second glass plate, a second solar cell, an interlayer, a first solar cell, and a first glass plate in this order and applying pressure.

[13] The method for manufacturing laminated glass according to

[12] , comprising providing a second solar cell on the second glass plate, providing an interlayer on the second solar cell, providing a first solar cell on the interlayer, and providing a first glass plate on the first solar cell.

[14] The method for manufacturing laminated glass according to

[12] , comprising preparing a second laminate having a second solar cell on the second glass plate and a first laminate having a first solar cell on the first glass plate, and arranging an interlayer and the first laminate on the second solar cell side surface of the second laminate.

[15] The method for manufacturing laminated glass according to

[12] , comprising further arranging an interlayer between the first glass plate and the first solar cell and / or between the second solar cell and the second glass plate.

[0008] This disclosure provides laminated glass that suppresses the degradation of solar cells and has excellent output for solar power generation, as well as a method for manufacturing the same.

[0009] This is a plan view showing an example of laminated glass. This is a cross-sectional view showing an example of the cross section along the cutting line II-II in Figure 1. This is a plan view showing an example of laminated glass. This is a cross-sectional view showing an example of the cross section along the cutting line IV-IV in Figure 3. This is a cross-sectional view showing an example of laminated glass. This is a cross-sectional view showing an example of laminated glass. This is a schematic diagram showing an example of a method for manufacturing laminated glass. This is a schematic diagram showing an example of a method for manufacturing laminated glass. This is a schematic diagram showing an example of a method for manufacturing laminated glass. This is a graph showing an example of a wavelength-external quantum efficiency curve. This is a graph showing an example of a wavelength-external quantum efficiency curve.

[0010] The embodiments for carrying out the invention will be described below with reference to the drawings. In each embodiment, identical components are denoted by the same reference numerals, and their descriptions are omitted or simplified. For clarity, the following descriptions and drawings are simplified as appropriate, and the scale of each component may differ significantly. Also for clarity, one direction of the main surface of the object may be defined as the X-axis, one direction of the main surface of the object perpendicular to the X-axis as the Y-axis, and the normal direction of the main surface of the object as the Z-axis. Note that the XY plane may be a curved surface. Furthermore, terms used in this specification to specify shapes, geometric conditions, and their degree, such as "parallel," "perpendicular," "orthogonal," and "identical," are not bound by strict meanings, but are interpreted to include a range in which similar functions can be expected. Unless otherwise specified, the numerical range indicated by "~" includes the numerical values ​​described before and after it as the lower and upper limits. In numerical ranges described in stages in this specification, the upper or lower limit described in one numerical range may be replaced by the upper or lower limit of another numerical range described in stages. Furthermore, in the numerical ranges described herein, the upper or lower limits of those ranges may be replaced with the values ​​shown in the examples. The outer edge of the object is referred to as the "periphery," and the area with width adjacent to the "periphery" of the object is referred to as the "peripheral portion." In addition, "vehicle" refers to a mobile body capable of mounting window glass, which typically includes automobiles, but also includes trains, ships, aircraft, etc. Furthermore, automobiles are not limited to passenger cars or private cars, but also include taxis, buses, trucks, etc. With respect to laminated glass, the "sunlight incident side" refers to the side from which sunlight is mainly incident, for example, the side located outside when installed on the aforementioned mobile body. In addition, the "sunlight transmission side" refers to the side from which sunlight that has passed through the laminated glass is emitted, for example, the side located inside when installed on the aforementioned mobile body. Specifically, it is a value obtained by multiplying the transmittance spectrum in the visible light wavelength range (380-780 nm) by a weighting coefficient obtained from the wavelength distribution of the daylight spectrum and relative luminous efficiency, and then taking a weighted average.

[0011] [Laminated Glass] First, the configuration of the laminated glass of this embodiment will be outlined with reference to Figures 1 and 2. Figure 1 is a plan view showing an example of the configuration of laminated glass according to the embodiment. Figure 2 is an example of a cross-section of the laminated glass shown in Figure 1 along the cutting line II-II. The laminated glass 100 shown in Figures 1 and 2 comprises a first glass plate 11 and a second glass plate 12, with a plurality of solar cells, namely first solar cells 21 and second solar cells 22, and an interlayer 31 between them, the interlayer 31 being positioned between the first solar cells 21 and the second solar cells. The first solar cells 21 and the second solar cells 22 have different wavelengths at which their external quantum efficiency is maximized. In the example of Figure 1, the laminated glass 100 is also provided with a shielding layer 41 at the periphery, and the first solar cells 21 are positioned across the entire surface of the opening. Although not shown, the layer configuration at the periphery is, for example, first glass plate 11 / interlayer 31 / second glass plate 12, in which case the solar cells are sealed by the periphery, and contact with oxygen and moisture is suppressed. Furthermore, although not shown, if the solar cell is a thin-film solar cell, a plate material may be provided on the main surface on the first glass plate 11 side, the main surface on the second glass plate 12 side, or both main surfaces of the solar cell. In addition, the ends of the solar cell may be sealed with the plate material and a curable resin or the like. In this disclosure, the first glass plate 11 represents a glass plate that is placed on the surface to which sunlight enters when the laminated glass 100 is installed. That is, for example, when the laminated glass 100 is installed on a vehicle, the first glass plate 11 is a glass plate that is placed on the outside of the vehicle. The second glass plate 12 represents an interior glass plate that is on the inside of the vehicle when the laminated glass 100 is installed on a vehicle. The laminated glass 100 can be suitably applied to, for example, roof glass, rear side glass, rear quarter glass, and extra glass for a vehicle, but it may also be applied to other parts of the vehicle as vehicle glass.

[0012] The laminated glass 100 may be flat, but when used in moving objects such as vehicles, a curved shape is preferred from the viewpoint of safety and design. The curved shape may be a simple curved shape curved in one direction (e.g., the X-axis direction), or a complex curved shape curved in both the first direction (e.g., the X-axis direction) and the second direction (e.g., the Y-axis direction). The angle between the first and second directions is arbitrary and may or may not be orthogonal. The curved shape includes three-dimensional shapes that are bent into more complex shapes. When the laminated glass 100 is curved, it is preferable that the laminated glass 100 is curved so as to be convex toward the outside of the vehicle. That is, it is preferable that the first glass plate 11 is curved so as to be convex toward the opposite side of the second glass plate 12, and it is preferable that the second glass plate 12 is curved so as to be convex toward the first glass plate 11. The shape of the main surface of the laminated glass 100 in plan view is an arbitrary shape depending on the installation location.

[0013] The shielding layer 41 is an optional configuration that can be provided as needed. The shielding layer 41 is an opaque layer and, for example, is provided in a strip shape along the periphery of the laminated glass 100. The shielding layer 41 is provided, for example, on the main sunlight-transmitting surface of the first glass plate 11 and / or the second glass plate 12, but is not limited to this. The shielding layer 41 is, for example, an opaque (for example, black) colored ceramic layer. Alternatively, the shielding layer 41 may be a light-shielding colored interlayer or colored film, or a combination of at least one of these and a colored ceramic layer. The colored film may be integrated with an infrared reflective film or the like.

[0014] Next, referring to FIGS. 3 and 4, a modified example of the laminated glass of the present embodiment will be described. FIG. 3 is a plan view showing a configuration example of the laminated glass according to the embodiment. FIG. 4 is an example of a cross section taken along the cutting line IV-IV of the laminated glass shown in FIG. 3. In the examples of FIGS. 3 and 4, the first solar cell 21 is in a form in which a plurality of solar cells are arranged in alignment in the plane direction (XY plane direction), and there are gaps between the solar cells. As shown in FIG. 4, an intermediate film 31 may enter the gaps. Although not shown, it may be in a form consisting of a plurality of second solar cells arranged in alignment in the plane direction, and both the first solar cell 21 and the second solar cell may be in such a form.

[0015] Hereinafter, the present invention will be described through embodiments of the invention, but the invention according to the claims is not limited to the following embodiments. Also, not all of the configurations described in the embodiments are necessarily essential as means for solving the problems. Also, the respective embodiments may be implemented in appropriate combinations.

[0016] <First Embodiment> Referring to FIGS. 1 and 2, the laminated glass of the first embodiment will be described. The laminated glass 100 of the first embodiment has each layer in the order of the first glass plate 11, the first solar cell 21, the intermediate film 31, the second solar cell 22, and the second glass plate 12 from the sunlight incident side.

[0017] (Glass Plate) The first glass plate 11 and the second glass plate 12 may be inorganic glass or organic glass. The inorganic glass and the organic glass only need to have transparency and may be colored. Examples of the inorganic glass include soda-lime glass, aluminosilicate glass, borosilicate glass, alkali-free glass, quartz glass, etc., and soda-lime glass is preferred. Examples of the organic glass include polycarbonate, acrylic resins such as polymethyl methacrylate, transparent resins such as polyvinyl chloride and polystyrene. Note that the materials of the first glass plate 11 and the second glass plate 12 may be the same or different. The inorganic glass may be either unstrengthened glass or strengthened glass. The strengthened glass may be either physical strengthened glass such as air-cooled strengthened glass or chemical strengthened glass.

[0018] The first glass plate 11 is preferably colorless from the viewpoint of the power generation efficiency of the solar cell, and clear glass or highly transmissive glass is preferable. The visible light transmittance of the first glass plate 11 is preferably 85% or more, more preferably 88% or more, and still more preferably 91% or more. Note that clear glass and highly transmissive glass have the following base compositions as an example. The numerical values are mass % based on oxides. (Composition of clear glass) SiO ２ : 65 to 75%, Al ２ O ３ : 0 to 5%, MgO: 0 to 6%, CaO: 5 to 15%, Na ２ O: 10 to 20%, K ２ O: 0 to 5%, Fe ２ O ３ Total iron content converted: 0 to 0.2%. (Composition of highly transmissive glass) SiO ２ : 65 to 80%, Al ２ O ３ : 0 to 5%, MgO: 0 to 12%, CaO: 0 to 15%, Na ２ O: 5 to 20%, K ２ O: 0 to 10%, Na ２ O + K ２ O: 5 to 20%, Fe ２ O ３ Total iron content converted: 0 to 0.04%.

[0019] The second glass plate 12 may be colored or colorless. Further, the second glass plate 12 may have an uneven layer for scattering light on the main surface, preferably on the main surface on the sunlight incident side. As the glass plate provided with the uneven layer for scattering light, ground glass is mentioned as an example, and it can be manufactured by a known method.

[0020] The forming method of the first glass plate 11 and the second glass plate 12 is not particularly limited. For example, in the case of inorganic glass, a glass plate formed by a float method or the like is preferable. For the bending forming of the first glass plate ills and the second glass plate 12, a gravity forming method, a press forming method, a roller forming method or the like may be used.

[0021] The thickness of the first glass plate 11 is preferably 1.1 mm or more, and more preferably 1.8 mm or more, from the viewpoint of strength such as resistance to flying stones. On the other hand, in order to prevent the mass of the laminated glass 100 from becoming too large and to suppress the fuel consumption of the vehicle, the thickness of the first glass plate 11 is preferably 3 mm or less, more preferably 2.8 mm or less, even more preferably 2.6 mm or less, even more preferably 2.2 mm or less, and particularly preferably 2.0 mm or less. The thickness of the first glass plate 11 is preferably 1.1 mm to 3 mm, more preferably 1.8 mm to 2.8 mm, even more preferably 1.8 mm to 2.6 mm, even more preferably 1.8 mm to 2.2 mm, and particularly preferably 1.8 mm to 2.0 mm. Furthermore, the thickness of the second glass plate 12 is preferably 0.3 mm or more, more preferably 0.5 mm or more, and even more preferably 0.7 mm or more, from the viewpoint of ease of handling. On the other hand, the thickness of the laminated glass 100 is preferably 2.3 mm or less, more preferably 2.1 mm or less, and even more preferably 1.9 mm or less, in order to prevent the mass of the laminated glass 100 from becoming too large and to suppress the fuel consumption of the vehicle. The thickness of the second glass plate 12 is preferably 0.3 mm to 2.3 mm, more preferably 0.5 mm to 2.1 mm, and even more preferably 0.7 mm to 1.9 mm.

[0022] (Interlayer) The interlayer 31 of the first embodiment is placed between the first solar cell 21 and the second solar cell 22. This relieves the stress on each solar cell and suppresses cracking of the solar cells.

[0023] The material of the interlayer 31 is preferably a thermoplastic resin, and preferably contains, for example, polyvinyl acetal (PVA), ethylene vinyl acetate copolymer (EVA), polyurethane (PU), ionomer resin, or cycloolefin copolymer (COP). Polyvinyl butyral (PVB) is preferred as the polyvinyl acetal (PVA). A resin composition containing a modified block copolymer hydride, as described in Japanese Patent No. 6065221, can also be suitably used. From the viewpoint of encapsulation of the solar cell, PVB or EVA is preferred.

[0024] In addition to the resin described above, the interlayer may contain one or more of the following additives: plasticizers, colorants, infrared absorbers, ultraviolet absorbers, antioxidants, fluorescent agents, adhesion modifiers, coupling agents, surfactants, heat stabilizers, light stabilizers, dehydrating agents, defoamers, antistatic agents, flame retardants, etc. In particular, if the interlayer contains PVB, it is preferable that it further contains a plasticizer.

[0025] The thickness of the interlayer is preferably 0.3 mm or more, and more preferably 0.5 mm or more. In embodiments having multiple interlayers, as described later, the thickness of the interlayer is the total thickness obtained by summing the thicknesses of each interlayer. When the thickness of the interlayer is 0.3 mm or more, preferably 0.5 mm or more, the laminated glass 100 has sufficient impact resistance. Furthermore, the thickness of the interlayer is preferably 3 mm or less. When the maximum thickness of the interlayer is 3 mm or less, the mass of the laminated glass 100 is suppressed. The maximum thickness of the interlayer is more preferably 2.8 mm or less, and even more preferably 2.6 mm or less.

[0026] The thickness of the thickest interlayer among the interlayers placed between solar cells (T ｉ ) and the thickness of the thickest solar cell among the multiple solar cells (T ｓ ) ratio (T ｓ / T ｉ The thickness (T) of the thickest interlayer among the interlayers placed between solar cells is preferably 5 or less, and more preferably 0.01 to 5, from the viewpoint of relieving the stress on the solar cells. ｉ ) and the thickness (T) of the first glass plate １ ) ratio (T １ / T ｉ From the viewpoint of impact resistance, 1 to 15 is preferred.

[0027] The interlayer 31 is preferably a highly transparent interlayer (clear interlayer). The visible light transmittance of the interlayer is preferably 85% or higher. The upper limit of the visible light transmittance of the interlayer is not particularly limited, but is, for example, around 95%.

[0028] (Solar Cells) The types of the first solar cell 21 and the second solar cell 22 are not particularly limited and include, for example, silicon solar cells such as monocrystalline silicon, polycrystalline silicon, and amorphous silicon; perovskite solar cells; organic solar cells such as dye-sensitized solar cells; and compound solar cells such as gallium arsenide-based solar cells, CIS solar cells, and CIGS solar cells. The first solar cell 21 and the second solar cell 22 may be of the same type or different types. Organic solar cells are preferred, and perovskite solar cells are more preferred, in terms of their ease of application to curved laminated glass and the ability to impart light transmittance through design. The first solar cell and the second solar cell may be of the same type or different types.

[0029] The following are examples of suitable combinations of the first solar cell 21 and the second solar cell 22. The combinations are described in the format "first solar cell / second solar cell". • Perovskite solar cell / silicon solar cell, • Perovskite solar cell / compound cell, • Perovskite solar cell / organic thin-film solar cell, • Compound cell / silicon solar cell, • Perovskite solar cell / perovskite solar cell.

[0030] From a performance standpoint, the thickness of a solar cell is preferably 50 μm to 500 μm for silicon solar cells, more preferably 100 μm to 300 μm, and even more preferably 100 μm to 200 μm. For organic solar cells or perovskite solar cells, the thickness is preferably 5 μm or less, more preferably 2 μm or less, and even more preferably 1 μm or less. A suitable thickness for a solar cell is, for example, 0.1 μm to 10 μm, preferably 0.2 μm to 5 μm, and more preferably 0.5 μm to 2 μm.

[0031] When the solar cell is a thin-film solar cell such as a perovskite solar cell, compound solar cell, or organic thin-film solar cell, the solar cell may be directly mounted on the first or second glass plate, or it may be mounted on a plate material. Furthermore, the thin-film solar cell may be mounted between two plate materials, and the ends of the solar cell may be sealed with a curable resin or the like. The plate material may be a glass substrate or a resin film. Specific examples of resin film materials include polyethylene terephthalate, polyethylene naphthalate, polyamide, polysulfone, polyethersulfone, polycarbonate, polystyrene, cyclic polyolefin, polyarylate, polyetherimide, polyetheretherketone, polyimide, aramid, polybutylene terephthalate, triacetylcellulose, polyurethane, and cycloolefin polymer. The glass substrate material may be the same as that of the first and second glass plates. The thickness of the plate material can be, for example, 2.1 mm or less, from the viewpoint of reducing the mass of the laminated glass. Alternatively, the thickness of the plate material can be 0.05 mm or more, from the viewpoint of sealing the solar cell and the strength of the plate material. Examples of the curable resins mentioned above include photocurable resins such as acrylic resins and thermosetting resins such as epoxy resins.

[0032] Referring to Figure 11, preferred combinations of multiple solar cells will be described. Figure 11 is a graph showing an example of a wavelength-external quantum efficiency curve. Curve A in Figure 11 is a graph showing the wavelength dependence of the external quantum efficiency of a single independent solar cell before it is incorporated into the laminated glass of the present invention, with wavelength λ ａ The external quantum efficiency takes its maximum value at this point. Curve B is a graph showing the wavelength dependence of the external quantum efficiency of an independent solar cell, different from the solar cell used in the measurement of curve A, and the wavelength λ ｂ The external quantum efficiency reaches its maximum value at this time. In the example shown in Figure 11, from the standpoint of superior power generation efficiency for the laminated glass 100 as a whole, it is preferable that the solar cell of curve A, i.e., the solar cell with the shortest wavelength at which the external quantum efficiency is maximized, is the first solar cell 21, and the solar cell of curve B is the second solar cell 22. From the viewpoint of power generation efficiency, the wavelength λ at which the external quantum efficiency is maximized is preferable. ａ and λｂ Difference | λ ｂ -λ ａ The | is preferably 100 nm or more, more preferably 150 nm or more, and even more preferably 200 nm or more.

[0033] Furthermore, from the viewpoint of power generation efficiency, it is preferable that the overlap portion of curve A and curve B is small, and the value obtained by the following (Equation 1) is preferably 0.3 or less, and more preferably 0.25 or less. ａｂ / ( S ａ +S ｂ -S ａｂ ) (Equation 1) However, S ａ This represents the area of ​​the surface formed by the wavelength of the solar cell closest to the incident sunlight surface and the external quantum efficiency curve, S ｂ This represents the area of ​​the surface formed by the wavelength of the solar cell furthest from the incident sunlight surface and the external quantum efficiency curve, S ａｂ This represents the area of ​​the superposition between the plane formed by the wavelength and external quantum efficiency curve of the solar cell closest to the sunlight incident surface and the plane formed by the wavelength and external quantum efficiency curve of the solar cell furthest from the sunlight incident surface.

[0034] Solar cells typically have wiring that electrically connects them to external circuits. This wiring can be in the form of a metal foil film, a transparent conductive film, or a wire, and in the case of a thin film, it may be formed on the solar cell itself.

[0035] In the first embodiment, the laminated glass, by providing an interlayer between multiple solar cells, reduces stress on the solar cells and suppresses crack formation, even when the glass plate is curved. In particular, the stress on the solar cells is further reduced when the interlayer is made of a thermoplastic resin. Furthermore, thermal stress on the solar cells during the manufacturing process of the laminated glass is also reduced, similarly suppressing crack formation. In addition, in the first embodiment, the solar cells are sealed by the glass plate and the interlayer, suppressing contact with oxygen and moisture. Moreover, because the main surface is a glass plate, it has excellent impact resistance and excellent scratch resistance for the solar cells. Thus, according to the first embodiment, a laminated glass with excellent reliability of solar cells and excellent output of solar power generation can be obtained.

[0036] <Second Embodiment> The laminated glass of the second embodiment will be described with reference to Figure 5. The laminated glass 100 of the second embodiment has the following layers in order from the sunlight incident side: first glass plate 11, first interlayer 32, first solar cell 21, second interlayer 31, second solar cell 22, third interlayer 33, and second glass plate 12. The laminated glass of the second embodiment differs from the first embodiment in that an interlayer is provided between the glass plate and the solar cell. The layers of the second embodiment will be described below, but the parts common to the first embodiment will be omitted from the description. Note that the interlayer 31 of the first embodiment corresponds to the second interlayer 31 of the second embodiment. The plan view may be the same as in Figure 1, or the same as in Figure 3.

[0037] (Interlayer) The material of the first interlayer 32 and the third interlayer 33, which are placed between the glass plate and the solar cell, is preferably a thermoplastic resin, and preferably contains, for example, polyvinyl acetal (PVA), ethylene vinyl acetate copolymer (EVA), polyurethane (PU), ionomer resin, or cycloolefin copolymer (COP). As polyvinyl acetal (PVA), polyvinyl butyral (PVB) is preferred. A resin composition containing a modified block copolymer hydride described in Japanese Patent No. 6065221 can also be suitably used. From the viewpoint of sealing the solar cell, PVB or EVA is preferred.

[0038] The first interlayer 32 is preferably a highly transparent interlayer (clear interlayer). The visible light transmittance of the interlayer is preferably 85% or higher. The upper limit of the visible light transmittance of the interlayer is not particularly limited, but is, for example, about 95%.

[0039] The third interlayer 33 may be a clear interlayer or a colored interlayer. An example of a colored interlayer is one obtained by adding a coloring agent to the thermoplastic resin mentioned above. The coloring agent is not particularly limited as long as it reduces the visible light transmittance, and examples include dyes, inorganic pigments, organic pigments, etc. Among these, inorganic pigments or organic pigments are preferred because there is little risk of fading with long-term use, and inorganic pigments are preferred because they have excellent lightfastness. The visible light transmittance of the colored interlayer is preferably 50% or less.

[0040] The first interlayer 32, the second interlayer 32, and the third interlayer 33 may be made of the same material or different materials, but from the viewpoint of sealing the solar cell, it is preferable that they contain the same resin. By containing the same resin, the first interlayer 32, the second interlayer 32, and the third interlayer 33 can be easily integrated at the periphery of the laminated glass 100, and contact between the solar cell and oxygen and water can be suppressed.

[0041] Although not shown, in the laminated glass of the second embodiment, it is not necessary to have either the first interlayer 32 or the third interlayer 33. That is, the following are examples of specific layer configurations of the laminated glass. Note that the description "a layer / b layer / c layer" indicates that the layers are stacked in the order of a layer, b layer, and c layer from the sunlight incident side. - First glass plate / first interlayer / first solar cell / second interlayer / second solar cell / third interlayer / second glass plate, - First glass plate / first solar cell / first interlayer / second solar cell / third interlayer / second glass plate, - First glass plate / first interlayer / first solar cell / second interlayer / second solar cell / second glass plate.

[0042] The laminated glass of the second embodiment has the same effects as the laminated glass of the first embodiment, and furthermore, by providing an interlayer between the glass plate and the solar cell, the stress on the solar cell is reduced and the sealing performance of the solar cell is also improved.

[0043] <Third Embodiment> The laminated glass of the third embodiment will be described with reference to Figures 6 and 7. The laminated glass 100 shown in the example of Figure 6 has the following layers in order from the sunlight incident side: first glass plate 11, first solar cell 21, first interlayer 31, second solar cell 22, second interlayer 32, third solar cell 23, and second glass plate 12. The laminated glass 100 shown in the example of Figure 7 also has the following layers in order from the sunlight incident side: first glass plate 11, first solar cell 21, second solar cell 22, first interlayer 31, third solar cell 23, and second glass plate 12. The laminated glass of the third embodiment differs from the first embodiment in that it has three layers of solar cells. The laminated glass of the third embodiment has improved power generation efficiency by having three layers of solar cells. In addition, by providing an interlayer between at least one of the multiple solar cells, the stress on the solar cells can be suppressed. The layers of the third embodiment will be described below, but the parts common to the first embodiment will be omitted from the description. The plan view may be the same as in Figure 1, or the same as in Figure 3.

[0044] (Solar Cells) The types of the first to third solar cells are not particularly limited and may be appropriately selected from the aforementioned silicon solar cells, perovskite solar cells, organic solar cells, compound solar cells, etc. The first to third solar cells may be of the same type or may be different.

[0045] Referring to Figure 12, a preferred combination of multiple solar cells will be described. Figure 12 is a graph showing an example of a wavelength-external quantum efficiency curve. It is preferable that each solar cell be arranged in order of the shortest wavelength that maximizes the external quantum efficiency, from the sunlight incident surface. Here, as described above, the external quantum efficiency was measured in the state of the independent solar cells before being incorporated into the laminated glass of the present invention. That is, it is preferable that the first solar cell 21 corresponds to curve A, the second solar cell 22 corresponds to curve C, and the third solar cell 23 corresponds to curve B.

[0046] From the viewpoint of power generation efficiency, the difference |λb-λa| between the wavelengths λa and λb at which the external quantum efficiency is maximized is preferably 100 nm or more, more preferably 150 nm or more, and even more preferably 200 nm or more. Also, from the viewpoint of power generation efficiency, it is preferable that the superposition area of ​​curve A and curve B is small. Specifically, when the area created by the wavelength-external quantum efficiency curve A, i.e., the area created by curve A and the wavelength axis is Sa, the area created by the wavelength-external quantum efficiency curve B is Sb, and the area of ​​the superposition of curve A and curve B is Sab, then Sab / (S ａ +S ｂ -S ａｂ The ratio is preferably 0.3 or less, and more preferably 0.25 or less. By combining such solar cells, laminated glass with superior power generation efficiency can be obtained.

[0047] Although not shown, in the laminated glass of the third embodiment, an interlayer may be provided between the first glass plate 11 and the first solar cell 21, and an interlayer may be provided between the second glass plate 12 and the third solar cell 23. Specific examples of these interlayers are the same as those described in the second embodiment. Specific layer configurations of the laminated glass are listed below. - First glass plate / First interlayer / First solar cell / Second interlayer / Second solar cell / Third interlayer / Third solar cell / Fourth interlayer / Second glass plate, - First glass plate / First solar cell / First interlayer / Second solar cell / Second interlayer / Third solar cell / Third interlayer / Second glass plate, - First glass plate / First solar cell / First interlayer / Second solar cell / Second interlayer / Third solar cell / Third interlayer / Second glass plate, - First glass plate / First solar cell / First interlayer / Second solar cell / Second interlayer / Third solar cell / Third interlayer / Second glass plate, - First glass plate / First solar cell / First interlayer / Second solar cell / First interlayer / Third solar cell / Second glass plate, - First glass plate / First solar cell / First interlayer / Second solar cell / Third solar cell / Second glass plate.

[0048] <Modification> The laminated glass of this disclosure may further have other layers. Examples of other layers include an anti-reflective coating, a heat-reflective coating, a light-adjusting sheet, a Low-E coating, etc. The laminated glass of this disclosure may also have four or more solar cells.

[0049] The anti-reflective coating is preferably placed on the side of the first glass plate 11 that is incident to sunlight, thereby increasing the amount of light that reaches the solar cell and improving power generation efficiency. Specific layer configurations of laminated glass equipped with an anti-reflective coating include: anti-reflective coating / first glass plate / first solar cell / interlayer / second glass plate / second solar cell / second glass plate, and the same applies to the laminated glass of the second and third embodiments.

[0050] A heat reflective layer and a light-adjusting sheet may be provided as needed to adjust the amount of light and / or heat transmitted. It is preferable to place the heat reflective layer and the light-adjusting sheet on the side of the solar cell that is exposed to sunlight. Specific layer configurations of laminated glass equipped with a heat reflective layer or a light-adjusting sheet include: • First glass plate / First solar cell / First interlayer / Second solar cell / Interlayer / Heat reflective sheet / Interlayer / Second glass plate, • First glass plate / First solar cell / First interlayer / Second solar cell / Interlayer / Light-adjusting sheet / Interlayer / Second glass plate, • First glass plate / First solar cell / First interlayer / Second solar cell / Interlayer / Heat reflective coating / Second glass plate, etc. The same applies to the laminated glass of the second and third embodiments.

[0051] The Low-E film is a film that suppresses radiant heat transfer, thereby limiting the passage of heat and improving heat shielding and insulation properties. A metal film or a conductive oxide film can be used. Specific layer configurations of laminated glass equipped with a Low-E film include: first glass plate / first solar cell / interlayer / second glass plate / second solar cell / second glass plate / Low-E film, and the same applies to the laminated glass of the second and third embodiments.

[0052] The laminated glass of this disclosure may have four or more layers of solar cells. Having four or more layers of solar cells improves power generation efficiency. On the other hand, from the standpoint of balancing power generation efficiency and manufacturing process, two to three layers of solar cells are preferable. Two or more of these variations may be combined.

[0053] [Method for Manufacturing Laminated Glass] Next, a method for manufacturing laminated glass will be described. Unless otherwise specified, the laminated glass of the first embodiment described above will be used as a representative example, but the second embodiment, the third embodiment, and modified versions can be manufactured in the same manner. Figure 8 is a schematic diagram showing an example of a method for manufacturing laminated glass. The laminated glass of this disclosure can be manufactured by arranging the second glass plate 12, the second solar cell 22, the interlayer film 31, the first solar cell 21, and the first glass plate 11 in this order and applying pressure. When providing each layer of the modified version, they may be pre-formed on the glass plate. For example, the anti-reflective film may be pre-formed on the first glass plate. The heat-reflective coating and Low-E film may be pre-formed on the second glass plate. The lamination is performed by placing the laminated body in a rubber bag, rubber chamber, resin bag, etc., and maintaining it for a predetermined time in a vacuum controlled at a gauge pressure of -100 kPa to -65 kPa at a temperature of approximately 70°C to 110°C. Heating conditions, temperature conditions, and lamination methods are selected as appropriate.

[0054] Furthermore, by performing a bonding process that involves heating and pressurizing the laminated glass under predetermined conditions, such as a temperature of 100°C to 150°C and an absolute pressure of 0.6 MPa to 1.3 MPa, a more durable laminated glass can be obtained. However, in some cases, this heating and pressurizing process may be omitted to simplify the process and to consider the characteristics of the material sealed within the laminated glass.

[0055] A method called "cold bending" may be used, in which either one or both of the first or second glass plates are joined in a state of elastic deformation relative to each other. Cold bending can be achieved by placing a laminate including an intermediate layer, a photovoltaic layer, etc., between the first and second glass plates, which are fixed by temporary fastening means such as tape, and using conventionally known pre-pressing devices such as nip rollers, rubber bags, or rubber chambers, and an autoclave.

[0056] Referring to Figures 9 and 10, the arrangement of each layer will be explained in more detail. In the example of Figure 9, a second solar cell 22 is provided on the second glass plate 12, an interlayer 31 is provided on the second solar cell 22, a first solar cell 21 is provided on the interlayer 31, and a first glass plate 11 is provided on the first solar cell 21. This method makes it possible to manufacture laminated glass on a single production line. In the example of Figure 10, a laminate with the second solar cell 22 provided on the second glass plate 12 and a laminate with the first solar cell 21 provided on the first glass plate 11 are prepared, and an interlayer 31 is placed between them and they are pressed together.

[0057] The total thickness of laminated glass is preferably 1.9 mm or more, and more preferably 2.8 mm or more, from the viewpoint of rigidity. On the other hand, from the viewpoint of the laminated glass having sufficient light transmittance and being lightweight, it is preferably 10 mm or less. The total thickness of laminated glass is, for example, 1.9 mm to 10 mm, and preferably 2.8 mm to 10 mm.

[0058] The applications of the laminated glass of this embodiment are not particularly limited, but it can be suitably used as laminated glass installed in moving objects such as vehicles, trains, ships, and aircraft, and can be used, for example, as roof glass for vehicles. Vehicles include, for example, passenger cars.

[0059] Although preferred embodiments have been described in detail above, the invention is not limited to the embodiments described above, and various modifications and substitutions can be made to the embodiments described above without departing from the scope of the claims.

[0060] This application claims priority based on Japanese Patent Application No. 2024-188087, filed on 25 October 2024, and incorporates all of its disclosures herein.

[0061] 11 First glass plate 12 Second glass plate 21, 22, 23 Solar cell 31, 32, 33 Interlayer 41 Shielding layer 100 Laminated glass

Claims

1. Laminated glass comprising a first glass plate, a second glass plate, a plurality of independent solar cells with different wavelengths that maximize external quantum efficiency, and an interlayer between the first and second glass plates, wherein the interlayer is placed between at least one solar cell.

2. The laminated glass according to claim 1, wherein the plurality of solar cells are arranged in order of decreasing wavelength from the sunlight incident surface to the wavelength that maximizes the external quantum efficiency.

3. The wavelength (λ) at which the external quantum efficiency of the solar cell closest to the surface of sunlight incidence is maximized. ａ ) and the wavelength (λ) at which the external quantum efficiency of the solar cell furthest from the incident sunlight is maximized. ｂ The difference (λ) ｂ -λ ａ The laminated glass according to claim 1, wherein the n-n 4. The laminated glass according to claim 1, wherein the value obtained by the following (Formula 1) is 0.3 or less. S ａｂ / (S ａ + S ｂ - S ａｂ )(Formula 1) However, S ａ represents the area of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell closest to the sunlight incident surface, S ｂ represents the area of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell farthest from the sunlight incident surface, S ａｂ represents the area of the overlapping portion of the surface formed by the wavelength and the external quantum efficiency curve of the solar cell closest to the sunlight incident surface and the surface formed by the wavelength and the external quantum efficiency curve of the solar cell farthest from the sunlight incident surface.

5. The thickness of the thickest interlayer among the interlayers placed between the solar cells (T ｉ The thickness of the thickest solar cell among the solar cells (T ｓ ) ratio (T ｓ / T ｉ The laminated glass according to claim 1, wherein the ratio is 5 or less.

6. The thickness of the thickest interlayer among the interlayers placed between the solar cells (T ｉ The thickness of the first glass (T) relative to ) １ ) ratio (T １ / T ｉ The laminated glass according to claim 1, wherein the ratio is 1 to 15.

7. The laminated glass according to claim 1, wherein each of the plurality of solar cells is independently selected from the group consisting of perovskite solar cells, silicon solar cells, compound solar cells, and organic thin-film solar cells.

8. The laminated glass according to claim 1, wherein the plurality of solar cells are two solar cells, and are arranged from the sunlight incident surface side in the order of perovskite solar cell, silicon solar cell, perovskite solar cell, compound solar cell, perovskite solar cell, organic thin film solar cell, compound solar cell, silicon solar cell, or perovskite solar cell, perovskite solar cell.

9. The laminated glass according to claim 1, wherein the visible light transmittance of the interlayer positioned on the side of the solar cell that is incident to sunlight is 85% or more.

10. The laminated glass according to claim 1, wherein the interlayer contains a thermoplastic resin.

11. A vehicle comprising laminated glass as described in any one of claims 1 to 10.

12. A method for manufacturing laminated glass according to any one of claims 1 to 10, comprising arranging a second glass plate, a second solar cell, an interlayer, a first solar cell, and a first glass plate in this order and applying pressure.

13. A method for manufacturing laminated glass according to claim 12, comprising: providing a second solar cell on a second glass plate; providing an interlayer on the second solar cell; providing a first solar cell on the interlayer; and providing a first glass plate on the first solar cell.

14. A method for manufacturing laminated glass according to claim 12, comprising preparing a second laminate having a second solar cell on a second glass plate and a first laminate having a first solar cell on a first glass plate, and arranging an interlayer and the first laminate on the second solar cell side of the second laminate.

15. A method for manufacturing laminated glass according to claim 12, further comprising arranging an interlayer between the first glass plate and the first solar cell, and / or between the second solar cell and the second glass plate.

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