Solar cell devices and solar cell modules

Abstract

Provided is a solar battery device in which warping of the solar battery device attributable to warping of solar battery cells is reduced. The solar battery device (1) comprises double-sided electrode-type solar battery cells (2), a connection member (6) that is for electrically connecting the solar battery cells (2), and a light-reception-side adhesion member (7) and a rear-side adhesion member (8) that are for adhering together the connection member (6) and the solar battery cells (2). The solar battery cells (2) are tandem solar battery cells each containing a first photoelectric conversion portion (10) that includes a crystal silicon substrate and a second photoelectric conversion portion (20) that is disposed further on the light reception surface side than the first photoelectric conversion portion (10) and includes a perovskite thin film. The light-reception-side adhesion member (7) is a sheet-shaped or film-shaped resin member that covers the connection member (6) on the light reception surface side of each solar battery cell (2), the rear-side adhesion member (8) is a sheet-shaped or film-shaped resin member that covers the connection member (6) on the rear surface side of each solar battery cell (2), and the volume of the rear-side adhesion member (8) is larger than the volume of the light-reception-side adhesion member (7).

Description

【Technical Field】 【0001】 The present invention relates to a solar cell device and a solar cell module. 【Background Art】 【0002】 A solar cell device in which a plurality of solar cells are connected by a connecting member such as a tab, and a solar cell module in which the solar cell device is sealed with a protective member such as glass or a transparent resin and a sealing material are known. As the solar cell, a crystalline silicon-based solar cell using a crystalline silicon substrate as a photoelectric conversion layer and a thin-film solar cell using an inorganic thin film such as an amorphous silicon thin film as a photoelectric conversion layer are known. Further, as a thin-film solar cell, a perovskite thin-film solar cell using a perovskite thin film which is an organic thin film (specifically, an organic / inorganic hybrid thin film) as a photoelectric conversion layer is known. 【0003】 In recent years, for the purpose of effectively using light in a wide wavelength range to improve the conversion efficiency of a solar cell, a multi-junction (tandem) type solar cell in which two photoelectric conversion parts including photoelectric conversion layers having different band gaps are stacked is known. For example, Patent Document 1 discloses a tandem type solar cell including a bottom cell (first photoelectric conversion part) including a crystalline silicon substrate as a photoelectric conversion layer and a top cell (second photoelectric conversion part) including a perovskite thin film as a photoelectric conversion layer. 【0004】 As such a tandem type solar cell, there are a two-terminal type in which a top cell and a bottom cell are connected in series, and a four-terminal type in which electrical extraction is performed separately from the top cell and the bottom cell. Further, a three-terminal type tandem type solar cell that can utilize the advantages of these two-terminal type and four-terminal type and has the possibility of further improving the photoelectric conversion efficiency has been devised (see, for example, Patent Document 2). 【Prior Art Documents】 【Patent Documents】 【0005】 [Patent Document 1] Japanese Patent Publication No. 2018-11058 [Patent Document 2] International Publication No. 2020 / 196288 [Overview of the project] [Problems that the invention aims to solve] 【0006】 In thin-film solar cells, an amorphous silicon thin film and a conductive amorphous silicon thin film are formed on a relatively hard glass or transparent resin as the photoelectric conversion layer. On the other hand, in crystalline silicon solar cells, a conductive amorphous silicon thin film is formed on a crystalline silicon substrate as the base for the photoelectric conversion layer, without using glass or transparent resin. Therefore, in tandem solar cells where a relatively thick perovskite thin film is formed on the light-receiving side of the crystalline silicon substrate, the difference in thickness between the layer laminated on the light-receiving side of the crystalline silicon substrate and the layer laminated on the back side of the crystalline silicon substrate causes relatively large warping of the solar cell during the manufacturing process of the solar cell device. As a result, relatively large warping occurs in the solar cell device. 【0007】 Therefore, in the manufacturing process of solar cell modules that enclose solar cell devices, connection defects such as delamination of connecting members such as tabs and cracking of solar cells can occur, resulting in a decrease in yield. 【0008】 The present invention aims to provide a solar cell device and solar cell module that reduce warping of solar cell devices caused by warping of solar cells. [Means for solving the problem] 【0009】 The solar cell device according to the present invention comprises a plurality of double-sided electrode solar cells, a plurality of connecting members that electrically connect adjacent solar cells, a plurality of light-receiving side adhesive members arranged on the light-receiving surface side of the solar cells and bonding the solar cells to the connecting members, and a plurality of back-side adhesive members arranged on the back side of the solar cells and bonding the solar cells to the connecting members. The solar cell is a tandem-type solar cell comprising a first photoelectric conversion unit including a crystalline silicon substrate, and a second photoelectric conversion unit arranged on the light-receiving surface side of the first photoelectric conversion unit and including a perovskite thin film. The light-receiving side adhesive members are sheet-like or film-like resin members that cover the connecting members on the light-receiving surface side of the solar cell, and the back-side adhesive members are sheet-like or film-like resin members that cover the connecting members on the back side of the solar cell, with the volume of the back-side adhesive members being greater than the volume of the light-receiving side adhesive members. 【0010】 The solar cell module according to the present invention comprises one or more solar cell devices, a light-receiving side protective member for protecting the light-receiving side of the solar cell device, a back-side protective member for protecting the back side of the solar cell device, and a sealing material disposed between the solar cell device and the light-receiving side protective member, and between the solar cell device and the back-side protective member, for sealing the solar cell device. [Effects of the Invention] 【0011】 According to the present invention, in solar cell devices and solar cell modules, it is possible to reduce the warping of the solar cell device caused by the warping of the solar cell. [Brief explanation of the drawing] 【0012】 [Figure 1] This is a schematic cross-sectional view showing a solar cell according to this embodiment. [Figure 2] This is a cross-sectional view of the solar cell device according to this embodiment. [Figure 3] Figure 2 shows a portion of the solar cell device as viewed from the light-receiving side. [Figure 4] It is a view of a part of the solar cell device shown in FIG. 2 as seen from the back side. [Figure 5] It is a cross-sectional view of the solar cell module according to the present embodiment. [Figure 6] It is a cross-sectional view of the solar cell device according to a modified example of the present embodiment. [Figure 7] It is a cross-sectional view of the solar cell device according to a modified example of the present embodiment. 【Mode for Carrying Out the Invention】 【0013】 Hereinafter, an example of an embodiment of the present invention will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts will be denoted by the same reference numerals. Also, for the sake of convenience, hatching, member reference numerals, etc. may be omitted, but in such a case, other drawings shall be referred to. 【0014】 (Solar Cell) FIG. 1 is a cross-sectional view schematically showing the solar cell according to the present embodiment. In FIG. 1 and the drawings described later, an XY orthogonal coordinate system is shown. The XY plane is a plane along the light-receiving surface and the back surface of the solar cell, the solar cell device, and the solar cell module described later. 【0015】 The solar cell 2 shown in FIG. 1 is a tandem type (multi-junction type) two-terminal solar cell including a first photoelectric conversion unit 10 (also referred to as a bottom cell B) and a second photoelectric conversion unit 20 (also referred to as a top cell T) laminated on the light-receiving surface side of the first photoelectric conversion unit 10. 【0016】 The first photoelectric conversion unit 10 (bottom cell B) includes a first semiconductor layer as a photoelectric conversion layer 11. The first semiconductor layer absorbs light and generates optical carriers. The first semiconductor layer as the photoelectric conversion layer 11 is a crystalline silicon substrate such as single-crystalline silicon or polycrystalline silicon. 【0017】 When the first semiconductor layer as the photoelectric conversion layer 11 is a single-crystal silicon substrate, examples of the first photoelectric conversion unit 10 include a diffused cell in which a diffusion layer of the second conductivity type is provided on the light-receiving surface side of the single-crystal silicon substrate of the first conductivity type, and a heterojunction cell in which silicon-based thin films are provided on both surfaces of the single-crystal silicon substrate of the first conductivity type. 【0018】 When the first semiconductor layer as the photoelectric conversion layer 11 is a single-crystal silicon substrate and in the case of a heterojunction cell provided with silicon-based thin films on the front and back of the single-crystal silicon substrate, the first photoelectric conversion unit 10 has a conductive silicon-based thin film 14 formed on the light-receiving surface side of the photoelectric conversion layer 11 and a conductive silicon-based thin film 15 formed on the back surface side of the photoelectric conversion layer 11. 【0019】 The single-crystal silicon substrate may be p-type or n-type. When comparing holes and electrons, electrons have a higher mobility. Therefore, when an n-type single-crystal silicon substrate is used, the conversion characteristics are particularly excellent. The conductive silicon-based thin films 14 and 15 are p-type silicon-based thin films or n-type silicon-based thin films. 【0020】 It is preferable that intrinsic silicon-based thin films 12 and 13 are provided between the single-crystal silicon substrate as the photoelectric conversion layer 11 and the conductive silicon-based thin films 14 and 15. By providing an intrinsic silicon-based thin film on the surface of the single-crystal silicon substrate, surface passivation can be effectively performed while suppressing the diffusion of impurities into the single-crystal silicon substrate. By providing intrinsic amorphous silicon thin films as the intrinsic silicon-based thin films12 and 13 on the surface of the single-crystal silicon substrate, a high passivation effect on the surface of the single-crystal silicon substrate can be obtained. 【0021】 The second photoelectric conversion unit 20 (top cell T) includes a thin second semiconductor layer as the photoelectric conversion layer 21. The second semiconductor layer absorbs light and generates photocarriers. The second semiconductor layer has a different band gap than the first semiconductor layer described above. Therefore, the first and second semiconductor layers have spectral sensitivity characteristics in different wavelength ranges. Consequently, in a stacked photoelectric conversion unit in which the first photoelectric conversion unit 10, which includes the first semiconductor layer as the photoelectric conversion layer 11, and the second photoelectric conversion unit 20, which includes the second semiconductor layer as the photoelectric conversion layer 21, are stacked, light of a wider wavelength can contribute to photoelectric conversion. 【0022】 Specifically, examples of thin films constituting the second semiconductor layer include organic semiconductor thin films, and more specifically, organic-inorganic hybrid semiconductor thin films. Examples of organic-inorganic hybrid semiconductor thin films include perovskite thin films containing a photosensitive material with a perovskite crystal structure. 【0023】 The compounds that make up perovskite-type crystalline materials are those with the general formula R 1 NH3M 1 X3 or HC(NH2)2M 1 It is represented by X3. In the formula, R 1 M is an alkyl group, preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably a methyl group. 1 X is a divalent metal ion, preferably Pb or Sn. X is a halogen, such as F, Cl, Br, or I. Note that all three X elements may be the same halogen element, or a mixture of multiple halogens may be used. 【0024】 A preferred example of a compound constituting a perovskite-type crystalline material is the compound of the formula CH3NH3Pb(I 1-x Br x Compounds represented by )3 (where 0≦x≦1) are examples. Perovskite materials can have their spectral sensitivity characteristics changed by changing the type and ratio of halogens. Perovskite semiconductor thin films can be formed by various dry processes or by solution deposition such as spin coating. 【0025】 When the photoelectric conversion layer 21 includes a perovskite semiconductor thin film, the second photoelectric conversion unit 20 has charge transport layers 24 and 25. One of the charge transport layers 24 and 25 is a hole transport layer, and the other is an electron transport layer. 【0026】 Examples of materials for the hole transport layer include polythiophene derivatives such as poly-3-hexylthiophene (P3HT) and poly(3,4-ethylenedioxythiophene) (PEDOT), fluorene derivatives such as 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-OMeTAD), carbazole derivatives such as polyvinylcarbazole, triphenylamine derivatives, diphenylamine derivatives, polysilane derivatives, and polyaniline derivatives. 【0027】 Examples of materials for the electron transport layer include metal oxides such as titanium oxide, zinc oxide, niobium oxide, zirconium oxide, and aluminum oxide. 【0028】 The first photoelectric conversion unit 10 and the second photoelectric conversion unit 20 described above are connected in series. The following combinations of charge transport layer 24 / charge transport layer 25 / conductive semiconductor layer 14 / conductive semiconductor layer 15 of the second photoelectric conversion unit 20 (top cell T) and the first photoelectric conversion unit 10 (bottom cell B) are listed below. • Hole transport layer (HTM) / Electron transport layer (ETM) / n-type amorphous silicon semiconductor layer (na-Si) / p-type amorphous silicon semiconductor layer (pa-Si): pn-np junction type • Electron transport layer (ETM) / Hole transport layer (HTM) / n-type amorphous silicon semiconductor layer (na-Si) / p-type amorphous silicon semiconductor layer (pa-Si): np-np junction type • Hole transport layer (HTM) / Electron transport layer (ETM) / p-type amorphous silicon semiconductor layer (pa-Si) / n-type amorphous silicon semiconductor layer (na-Si): pn-pn junction type • Electron transport layer (ETM) / Hole transport layer (HTM) / p-type amorphous silicon semiconductor layer (pa-Si) / n-type amorphous silicon semiconductor layer (na-Si): np-pn junction type 【0029】 An intermediate layer (not shown) may be provided between the first photoelectric conversion unit 10 and the second photoelectric conversion unit 20. The intermediate layer is provided for purposes such as adjusting the band gap between the two stacked photoelectric conversion units, selective carrier movement, tunnel junction formation, and wavelength-selective reflection. The configuration of the intermediate layer is selected according to the type and combination of the photoelectric conversion units 10 and 20. The intermediate layer can also be omitted by giving the function of an intermediate layer to the conductive semiconductor layer 14 and charge transport layer 25 provided at the interface between the first photoelectric conversion unit 10 and the second photoelectric conversion unit 20. 【0030】 On the main surface of the second photoelectric conversion unit 20 opposite to the first photoelectric conversion unit 10, i.e., the light-receiving surface side of the solar cell 2, an electrode 31 for extracting photogenerated carriers is formed. On the main surface of the first photoelectric conversion unit 10 opposite to the second photoelectric conversion unit 20, i.e., the back surface side of the solar cell 2, an electrode 32 for extracting photogenerated carriers is formed. 【0031】 Electrode 31 may include a transparent electrode 311 and a metal electrode 312. Similarly, electrode 32 may include a transparent electrode 321 and a metal electrode 322. Preferably, the transparent electrodes 311 and 321 are made of metal oxides such as ITO, zinc oxide, or tin oxide. Preferably, the metal electrodes 312 and 322 are made of silver, copper, or aluminum. 【0032】 The metal electrode 312 on the light-receiving surface side is a grid-shaped or slit-shaped electrode. Preferably, the metal electrode 322 on the back side is also a grid-shaped or slit-shaped electrode. This allows light from both the light-receiving surface and the back side to be incident, improving the photoelectric conversion efficiency. 【0033】 (Solar cell devices) Figure 2 is a cross-sectional view of the solar cell device according to this embodiment, Figure 3 is a view of a part of the solar cell device shown in Figure 2 from the light-receiving side, and Figure 4 is a view of a part of the solar cell device shown in Figure 2 from the back side. As shown in Figures 2 to 4, the solar cell device 1 comprises a plurality of solar cells 2, a plurality of connecting members 6, a plurality of light-receiving side adhesive members 7, and a plurality of back side adhesive members 8. 【0034】 Multiple solar cells 2 are arranged, for example, in the Y direction. Connecting members 6 electrically connect adjacent solar cells 2. Specifically, one end of the connecting member 6 is connected to the electrode 31 on the light-receiving surface side of one solar cell 2, and the other end of the connecting member 6 is connected to the electrode 32 on the back side of the other solar cell 2. Multiple solar cells 2 connected in this string-like manner are called a solar cell string (solar cell device). 【0035】 As the connecting member 6, known interconnectors such as tabs are used. For example, as the connecting member 6, examples include ribbon wire made of a copper core material coated with a low-melting-point metal or solder, a conductive film formed of a thermosetting resin film containing low-melting-point metal particles or fine metal particles, or a member formed of a knitted or woven fabric made by braiding a plurality of conductive wires (see, for example, Japanese Patent Publication No. 2016-219799 or Japanese Patent Publication No. 2014-3161). 【0036】 The connecting member 6 and the electrodes 31 and 32 of the solar cell 2 may be connected via a conductive adhesive member. As the conductive adhesive member, a conductive film formed from a thermosetting resin film containing low-melting-point metal particles or metal microparticles, a conductive adhesive formed from low-melting-point metal microparticles or metal microparticles and a binder, or a solder paste containing solder particles can be used. 【0037】 Furthermore, the connecting member 6 and the electrode 31 of the solar cell 2 are connected by being covered with a light-receiving adhesive member 7. Also, the connecting member 6 and the electrode 32 of the solar cell 2 are connected by being covered with a back-side adhesive member 8. 【0038】 The light-receiving adhesive member 7 is positioned on the light-receiving surface side of the solar cell 2 and adheres the electrodes 31 of the solar cell 2 to the connecting member 6. Specifically, the light-receiving adhesive member 7 is a sheet-like or film-like resin member that adheres the electrodes 31 of the solar cell 2 to the connecting member 6 by covering the connecting member 6 on the light-receiving side of the solar cell 2. 【0039】 The back adhesive member 8 is positioned on the back side of the solar cell 2 and adheres the electrodes 32 of the solar cell 2 to the connecting member 6. Specifically, the back adhesive member 8 is a sheet-like or film-like resin member that adheres the electrodes 32 of the solar cell 2 to the connecting member 6 by covering the connecting member 6 on the back side of the solar cell 2. 【0040】 The volume of the back adhesive member 8 is greater than the volume of the light-receiving adhesive member 7. More specifically, the volume of the back adhesive member 8 that adheres to the back surface of the solar cell 2 and the connecting member 6 is greater than the volume of the light-receiving adhesive member 7 that adheres to the light-receiving surface of the solar cell 2 and the connecting member 6. 【0041】 For example, as shown in Figures 3 and 4, the thickness of the back adhesive member 8 may be greater than the thickness of the light-receiving adhesive member 7. More specifically, the thickness of the back adhesive member 8 that adheres to the back surface of the solar cell 2 and the connecting member 6 may be greater than the thickness of the light-receiving adhesive member 7 that adheres to the light-receiving surface of the solar cell 2 and the connecting member 6. 【0042】 Furthermore, as shown in Figures 3 and 4, the area of ​​the back adhesive member 8 may be larger than the area of ​​the light-receiving adhesive member 7. More specifically, the adhesion area of ​​the back adhesive member 8 that adheres to the back surface of the solar cell 2 and the connecting member 6 may be larger than the adhesion area of ​​the light-receiving adhesive member 7 that adheres to the light-receiving surface of the solar cell 2 and the connecting member 6. 【0043】 Here, Figures 6 and 7 are cross-sectional views of a modified solar cell device according to this embodiment. As shown in Figure 6, the area of ​​the back adhesive member 8 is the same as the area of ​​the light-receiving adhesive member 7, but the thickness of the back adhesive member 8 may be greater than the thickness of the light-receiving adhesive member 7. Alternatively, as shown in Figure 7, the thickness of the back adhesive member 8 is the same as the thickness of the light-receiving adhesive member 7, but the area of ​​the back adhesive member 8 may be greater than the area of ​​the light-receiving adhesive member 7. 【0044】 The above-mentioned adhesion thickness is the thickness of the light-receiving adhesive member 7 or the back-side adhesive member 8 at the adhesion portion, and the adhesion area is the area of ​​the light-receiving adhesive member 7 or the back-side adhesive member 8 at the adhesion portion. Furthermore, the adhesion volume is the product of the adhesion thickness and the adhesion area. 【0045】 Examples of materials for the light-receiving adhesive member 7 and / or the back-side adhesive member 8 include light-transmitting resins such as ethylene / vinyl acetate copolymer (EVA), ethylene / α-olefin copolymer, ethylene / vinyl acetate / triallyl isocyanurate (EVAT), polyvinyl butyrate (PVB), acrylic resin, urethane resin, epoxy resin, or silicone resin. The light-receiving adhesive member 7 and the back-side adhesive member 8 may use the same material or different materials. 【0046】 According to the material of the light-receiving adhesive member 7 described above, the light-receiving adhesive member 7 has light transmittance. Furthermore, if the material of the back-side adhesive member 8 is also the same as described above, the back-side adhesive member 8 also has light transmittance, which is preferable. As a result, not only light from the light-receiving surface but also light from the back side can be incident, improving the photoelectric conversion efficiency. 【0047】 Furthermore, it is preferable that the difference between the refractive index of the light-receiving adhesive member 7 and the refractive index of the sealing material 5, described later, be 0.05 or less. It is also preferable that the difference between the refractive index of the back adhesive member 8 and the refractive index of the sealing material 5, described later, be 0.05 or less. For example, it is acceptable if the material of the light-receiving adhesive member 7 and / or the back adhesive member 8 is ethylene / vinyl acetate copolymer (EVA) or ethylene / α-olefin copolymer, and the material of the sealing material 5, described later, is ethylene / vinyl acetate copolymer (EVA) or ethylene / α-olefin copolymer, and the copolymer ratio of the materials of the light-receiving adhesive member 7 and / or the back adhesive member 8 is the same or different. 【0048】 Furthermore, it is preferable that the softening temperature of the light-receiving adhesive member 7 is higher than that of the sealing material 5, which will be described later, and that the softening temperature of the back-side adhesive member 8 is higher than that of the sealing material 5, which will be described later. For example, it is acceptable if the materials of the light-receiving adhesive member 7 and the back-side adhesive member 8 are ethylene / vinyl acetate copolymer (EVA) or ethylene / α-olefin copolymer, and the material of the sealing material 5, which will be described later, is ethylene / vinyl acetate copolymer (EVA) or ethylene / α-olefin copolymer, and the copolymer ratio of the materials of the light-receiving adhesive member 7 and / or the back-side adhesive member 8 is different. 【0049】 (Solar modules) Figure 5 is a cross-sectional view of a solar cell module according to this embodiment. As shown in Figure 1, the solar cell module 100 includes one or more solar cell devices 1. 【0050】 The solar cell device 1 is sandwiched between a light-receiving protective member 3 and a back-side protective member 4. A liquid or solid sealing material 5 is filled between the light-receiving protective member 3 and the back-side protective member 4, thereby sealing the solar cell device 1. 【0051】 The sealing material 5 seals and protects the solar cell device 1, i.e., the solar cell 2, and is interposed between the light-receiving surface of the solar cell 2 and the light-receiving protective member 3, and between the back surface of the solar cell 2 and the back protective member 4. The shape of the sealing material 5 is not particularly limited, and for example, it can be in the form of a sheet. This is because a sheet shape makes it easy to cover the surface and back surface of the planar solar cell 2. 【0052】 The material of the encapsulant 5 is not particularly limited, but it is preferable that it has the property of transmitting light (light transmission). Furthermore, it is preferable that the material of the encapsulant 5 has adhesive properties that allow the solar cell 2, the light-receiving protective member 3, and the back-side protective member 4 to adhere together. Examples of such materials include light-transmitting resins such as ethylene / vinyl acetate copolymer (EVA), ethylene / α-olefin copolymer, ethylene / vinyl acetate / triallyl isocyanurate (EVAT), polyvinyl butyrate (PVB), acrylic resin, urethane resin, or silicone resin. 【0053】 The light-receiving protective member 3 protects the solar cell 2 by covering its surface (light-receiving surface) with the solar cell device 1, i.e., the solar cell 2, via the sealing material 5. The shape of the light-receiving protective member 3 is not particularly limited, but a plate or sheet shape is preferred because it indirectly covers the planar light-receiving surface. 【0054】 The material of the light-receiving protective member 3 is not particularly limited, but like the sealing material 5, a material that is light-transmitting yet resistant to ultraviolet light is preferred. Examples include glass, or transparent resins such as acrylic resin or polycarbonate resin. The surface of the light-receiving protective member 3 may be processed to have an uneven surface, or it may be covered with an anti-reflective coating layer. This is because the light-receiving protective member 3 makes it difficult for the received light to be reflected, allowing more light to be guided to the solar cell device 1. 【0055】 The back-side protective member 4 protects the solar cell 2 by covering its back surface via the sealing material 5. The shape of the back-side protective member 4 is not particularly limited, but like the light-receiving side protective member 3, it is preferably plate-shaped or sheet-shaped as it indirectly covers the surface back surface. 【0056】 The material for the back protective member 4 is not particularly limited, but a material that prevents the intrusion of water, etc. (high water-resistant material) is preferred. Examples include resin films such as polyethylene terephthalate (PET), polyethylene (PE), olefin resins, fluororesins, or silicone resins, or laminates of a translucent plate-shaped resin member such as glass, polycarbonate, or acrylic and a metal foil such as aluminum foil. 【0057】 According to the materials of the light-receiving protective member 3 and the sealing material 5 described above, the light-receiving protective member 3 and the sealing material 5 are light-transmitting. Furthermore, if the material of the back-side protective member 4 is also the same as described above, the back-side protective member 4 is also light-transmitting, which is preferable. As a result, not only light from the light-receiving surface but also light from the back side can be incident, improving the photoelectric conversion efficiency. 【0058】 (Method of manufacturing solar cell devices) Next, a method for manufacturing a solar cell device according to this embodiment will be described. (1) First, arrange the solar cells 2. (2) Next, a conductive adhesive is placed on the electrodes 31 and 32 of the solar cell 2. (3) Next, the connecting member 6 is placed on the electrodes 31 and 32 of the solar cell 2. (4) Next, the light-receiving adhesive member 7 is placed on the light-receiving side of the solar cell 2 so as to cover the connecting member 6, and the back adhesive member 8 is placed on the back side of the solar cell 2 so as to cover the connecting member 6. Note that steps (1) through (4) can be rearranged. 【0059】 (5) Next, the light-receiving adhesive member 7 and the connecting member 6 are bonded to the light-receiving surface side of the solar cell 2 by heat treatment, and the back-side adhesive member 8 and the connecting member 6 are bonded to the back side of the solar cell 2 by heat treatment. 【0060】 (Manufacturing method for solar cell modules) Next, a method for manufacturing a solar cell device according to this embodiment will be described. (6) Place the solar cell devices, jumper wires, and lead wires to connect the solar cell strings together. (7) Next, the light-receiving protective member, sealing material, solar cell device, sealing material, and back-side protective member are arranged in this order. (8) Next, a known heating and pressing treatment is performed. This results in a solar cell module 100 in which the solar cell device 1 is sealed by the light-receiving protective member 3, the back protective member 4, and the sealing material 5. 【0061】 In the manufacturing process of the solar cell device 1 described above, during step (5), the heat treatment for bonding the connecting member 6 to the solar cell 2, warping of the solar cell 2 may occur. Specifically, in a tandem-type solar cell 2 in which a relatively thick perovskite thin film is formed on the light-receiving side of the crystalline silicon substrate, warping of the solar cell 2 may occur due to the difference in thickness between the layer laminated on the light-receiving side of the crystalline silicon substrate and the layer laminated on the back side of the crystalline silicon substrate. As a result, warping of the solar cell device 1 may occur. 【0062】 Therefore, in the manufacturing process of the solar cell module 100 described above, procedure (8), the heating and pressurizing process during sealing of the solar cell device 1, connection defects such as delamination of the connecting member 6 and cracking defects of the solar cell 2 may occur. 【0063】 In this regard, in this embodiment, not only the conductive adhesive of step (2) but also the light-receiving adhesive member 7 and the back-side adhesive member 8 of step (4) are used. 【0064】 In other words, according to the solar cell device 1 and solar cell module 100 of this embodiment, the light-receiving adhesive member 7 covers the connecting member 6 on the light-receiving surface side of the solar cell 2, and the back-side adhesive member 8 covers the connecting member 6 on the back side of the solar cell 2. This allows the connecting member 6 to be fixed, and in step (8) of the manufacturing process of the solar cell module 100, the heating and pressurizing process when sealing the solar cell device 1 can be reduced, resulting in poor connections (peeling) of the connecting member 6. Furthermore, the buffering effect of the light-receiving adhesive member 7 and the back-side adhesive member 8 can reduce crack defects in the solar cell 2. 【0065】 Furthermore, according to the solar cell device 1 and solar cell module 100 of this embodiment, the volume (i.e., thickness and / or area) of the back-side adhesive member 8 is larger than the volume (i.e., thickness and / or area) of the light-receiving side adhesive member 7. This makes it possible to reduce the difference between the thickness of the layer laminated on the light-receiving side of the crystalline silicon substrate and the thickness of the layer laminated on the back side of the crystalline silicon substrate in a tandem-type solar cell 2 in which a relatively thick perovskite thin film is formed on the light-receiving side of the crystalline silicon substrate. Therefore, in step (5) of the manufacturing process of the solar cell device 1, the heat treatment for bonding the connecting member 6 to the solar cell 2 can be reduced, and the warping of the solar cell device 1 caused by the warping of the solar cell 2 can be reduced. As a result, connection failures (peeling) of the connecting member 6 caused by the warping of the solar cell 2, or in other words, the warping of the solar cell device 1, can be reduced. In addition, in step (8) of the manufacturing process of the solar cell module 100, the heat and pressurization treatment when sealing the solar cell device 1 can be reduced, connection failures such as peeling of the connecting member 6 and cracking defects of the solar cell can be reduced. In this way, defects in the manufacturing process of the solar cell device 1 and solar cell module 100 can be reduced, and the yield can be improved. 【0066】 Incidentally, in recent years, the size of solar cells has been increasing. As solar cells become larger, there is a tendency for the warping of the solar cells and solar cell devices to increase. The features of this embodiment are more effective in solar cell devices and solar cell modules equipped with such large tandem solar cells. 【0067】 Furthermore, in recent years, bifacial solar cells have emerged. In such bifacial solar cells, if the metal electrodes on the back side are grid-like or slit-like, the warping of the solar cell and the solar device tends to increase. This method is effective in solar devices and solar modules equipped with tandem solar cells of this bifacial electrode type, i.e., those having grid-like or slit-like back metal electrodes. 【0068】 Furthermore, in this embodiment, the difference between the refractive index of the light-receiving adhesive member 7 and the refractive index of the sealing material 5, and the difference between the refractive index of the back-side adhesive member 8 and the refractive index of the sealing material 5, are 0.05 or less. This reduces reflection between the light-receiving adhesive member 7 and the sealing material 5, and / or between the back-side adhesive member 8 and the sealing material 5, thereby improving photoelectric conversion efficiency. It also enhances the aesthetic design. 【0069】 Furthermore, in this embodiment, the softening temperature of the light-receiving adhesive member 7 and the back-side adhesive member 8 is higher than the softening temperature of the sealing material 5. As a result, in step (5) of the manufacturing process of the solar cell device 1, after the heat treatment to bond the connecting member 6 to the solar cell 2, and in step (8) of the manufacturing process of the solar cell module 100, the heating and pressurizing treatment when sealing the solar cell device 1, the light-receiving adhesive member 7 and the back-side adhesive member 8 do not soften, thereby reducing connection failures (peeling) of the connecting member 6. 【0070】 Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications and variations are possible. For example, the embodiments and modifications described above exemplify solar cell devices and solar cell modules equipped with two-terminal tandem solar cells. However, the features of the present invention are also applicable to solar cell devices and solar cell modules equipped with four-terminal tandem solar cells, and also to solar cell devices and solar cell modules equipped with three-terminal tandem solar cells. [Explanation of symbols] 【0071】 1. Solar cell devices 2 solar cells 3. Light-receiving side protective member 4. Back side protective material 5. Sealing material 6. Connecting Members 7. Light-receiving adhesive member 8. Backside adhesive material 10,B First photoelectric conversion unit (bottom cell) 11. Photoelectric conversion layer (first semiconductor layer) 12,13 Intrinsic semiconductor layer (intrinsic silicon-based thin film) 14,15 Conductive semiconductor layer (conductive silicon-based thin film) 20,T Second photoelectric conversion unit (top cell) 21 Photoelectric conversion layer (second semiconductor layer) 24,25 Charge transport layer 31,32 electrode 311,321 Transparent electrode 312,322 Metal electrode 100 solar modules

Claims

[Claim 1] Multiple double-sided electrode solar cells, Multiple connecting members that electrically connect adjacent solar cells, A plurality of light-receiving adhesive members are arranged on the light-receiving surface side of the solar cell and bond the solar cell and the connecting member, A plurality of back-side adhesive members are arranged on the back side of the solar cell and bond the solar cell and the connecting member, Equipped with, The aforementioned solar cell is A first photoelectric conversion unit including a crystalline silicon substrate, A second photoelectric conversion unit, which includes a perovskite thin film, is positioned on the light-receiving surface side of the first photoelectric conversion unit. It is a tandem-type solar cell that includes, The light-receiving adhesive member is a sheet-like or film-like resin member that covers the connecting member on the light-receiving surface side of the solar cell. The aforementioned back-side adhesive member is a sheet-like or film-like resin member that covers the connecting member on the back side of the solar cell. The volume of the back-side adhesive member is larger than the volume of the light-receiving side adhesive member. Solar cell devices. [Claim 2] The solar cell device according to claim 1, wherein the thickness of the back adhesive member is greater than the thickness of the light-receiving adhesive member. [Claim 3] The solar cell device according to claim 1 or 2, wherein the area of ​​the back adhesive member is larger than the area of ​​the light-receiving adhesive member. [Claim 4] The light-receiving adhesive member and the back-side adhesive member have light transmittance, The solar cell device according to claim 1 or 2, wherein the electrodes on the light-receiving surface side and the electrodes on the back side of the solar cell have grid-shaped or slit-shaped metal electrodes. [Claim 5] One or more solar cell devices according to claim 1 or 2, A light-receiving side protective member that protects the light-receiving side of the solar cell device, A back-side protective member that protects the back side of the solar cell device, A sealing material is disposed between the solar cell device and the light-receiving protective member, and between the solar cell device and the back-side protective member, to seal the solar cell device. Equipped with, The softening temperatures of the light-receiving adhesive member and the back-side adhesive member are higher than the softening temperature of the sealing material. Solar cell module. [Claim 6] The light-receiving protective member, the sealing material, the light-receiving adhesive member, the back-side protective member, and the back-side adhesive member are light-transmitting, The electrodes on the light-receiving surface side and the electrodes on the back side of the solar cell have grid-shaped or slit-shaped metal electrodes. The solar cell module according to claim 5. [Claim 7] The solar cell module according to claim 6, wherein the difference between the refractive index of the light-receiving adhesive member and the refractive index of the sealing material, and the difference between the refractive index of the back adhesive member and the refractive index of the sealing material are 0.05 or less.

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