Solar battery module

Abstract

To provide a solar battery module which suppresses the generation of air bubbles between a butyl rubber member and a protective member, thereby increasing efficiency of use of light.SOLUTION: A solar battery module 100 includes: a plurality of thin-film solar battery submodules 10 each including a transparent base material 12 and a thin-film solar battery cell 20 formed on the transparent base material 12; a light receiving side protective member 3; a back side protective member 4; a light receiving side sealing material 5a; a back side sealing material 5b; a butyl rubber member 8 sealing around the submodules 10 and around the back side sealing material 5b between the transparent base material 12 of each of the submodules 10 and the back side protective member 4; and a metal thin film 9 disposed so as to overlap the butyl rubber member 8, around the submodules 10 on a side of the transparent base material 12 of each of the submodule 10.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a solar cell module. [Background technology]

[0002] Patent Document 1 discloses a solar cell module including a perovskite-based (thin film-based) solar cell submodule. The solar cell submodule includes a perovskite-based (thin film-based) solar cell cell formed on a transparent substrate.

[0003] In such a solar cell module, the solar cell submodule is sealed with, for example, a light-receiving side glass plate (protective member) and a back side glass plate (protective member), and a sealing material. Furthermore, in such a solar cell module, since the perovskite-based (thin film-based) solar cell submodule is vulnerable to humidity, the peripheral edges are sealed with a butyl rubber member. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. 2020 / 208854 Summary of the Invention [Problem to be solved by the invention]

[0005] When a solar cell submodule uses, for example, a glass plate as the transparent substrate, the solar cell module is composed of three glass plates. In this manner, with a three-glass plate composition, there is a large unevenness (step) between the areas where the transparent substrate of the solar cell submodule is present and the areas where it is not. As a result, during thermal compression sealing of the solar cell module, the sealant and butyl rubber do not adequately adapt to the uneven shape due to flow, and air bubbles are likely to occur between the butyl rubber member and the glass plate (especially the light-receiving side glass plate), leading to poor appearance and deterioration of the solar cell module.

[0006] In addition, because butyl rubber is black, the light incident on the butyl rubber cannot be used effectively.

[0007] An object of the present invention is to provide a solar cell module that suppresses the generation of air bubbles between a butyl rubber member and a protective member (particularly a light-receiving side protective member) and improves the effective use of light. [Means for solving the problem]

[0008] The solar cell module according to the present invention includes a plurality of thin-film solar cell submodules, each of which has a transparent substrate and a thin-film solar cell formed on the transparent substrate; a light-receiving-side protective member arranged on the transparent substrate side of the plurality of thin-film solar cell submodules; a light-receiving-side sealing material arranged between the plurality of thin-film solar cell submodules and the light-receiving-side protective member; a back-side protective member arranged on the side of the plurality of thin-film solar cell submodules opposite the transparent substrate; a back-side sealing material arranged between the plurality of thin-film solar cell submodules and the back-side protective member; a butyl rubber member that seals the periphery of the plurality of thin-film solar cell submodules and the periphery of the back-side sealing material between the transparent substrate and the back-side protective member of the plurality of thin-film solar cell submodules ... Effect of the Invention

[0009] According to the present invention, in a solar cell module, it is possible to suppress the generation of air bubbles between a butyl rubber member and a protective member (particularly a light-receiving side protective member), thereby improving the effective use of light. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic cross-sectional view of a solar cell module according to an embodiment of the present invention. [Diagram 2] 1 is a schematic plan view showing a solar cell module according to an embodiment of the present invention from the light-receiving surface side. [Diagram 3] 1 is a schematic plan view showing a solar cell module according to an embodiment of the present invention from the back surface side. [Figure 4] FIG. 4 is a schematic cross-sectional view of a solar cell submodule in the solar cell module shown in FIGS. 1 to 3. [Diagram 5] 1 is a schematic cross-sectional view of a solar cell module according to a first comparative example. [Figure 6] FIG. 11 is a schematic cross-sectional view of a solar cell module according to a second comparative example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings. In each drawing, the same or corresponding parts are denoted by the same reference numerals. For convenience, hatching and reference numerals may be omitted, in which case other drawings shall be referred to.

[0012] (Solar cell module) Fig. 1 is a schematic cross-sectional view of the solar cell module according to this embodiment, Fig. 2 is a schematic plan view showing the solar cell module according to this embodiment from the light-receiving surface side, and Fig. 3 is a schematic plan view showing the solar cell module according to this embodiment from the back surface side. Note that a light-receiving side protection member 3 and a light-receiving side sealing material 5a, which will be described later, are omitted in Fig. 2, and a back side protection member 4 and a back side sealing material 5b, which will be described later, are omitted in Fig. 3.

[0013] 1 to 3 includes a plurality of thin-film solar cell submodules 10 arranged two-dimensionally. Each solar cell submodule 10 has a transparent base material 12 and a plurality of thin-film solar cells 20 formed on the transparent base material 12. The solar cell submodule 10 will be described in detail later.

[0014] The solar cell submodule 10 is sandwiched between a light-receiving-side protective member 3 and a back-side protective member 4. A liquid or solid light-receiving-side sealing material 5a and a back-side sealing material 5b are filled between the light-receiving-side protective member 3 and the back-side protective member 4, thereby sealing the solar cell submodule 10.

[0015] The light-receiving-side sealing material 5a and the back-side sealing material 5b seal and protect the solar cell submodule 10. The light-receiving-side sealing material 5a is interposed between the light-receiving-side surface (the surface on the transparent base material 12 side) of the solar cell submodule 10 and the light-receiving-side protection member 3. The back-side sealing material 5b is interposed between the back-side surface (the surface opposite the transparent base material 12) of the solar cell submodule 10 and the back-side protection member 4. The shapes of the light-receiving-side sealing material 5a and the back-side sealing material 5b are not particularly limited, and may be, for example, a sheet shape. This is because the sheet shape makes it easy to cover the front and back surfaces of the planar solar cell submodule 10.

[0016] The materials of the light-receiving-side sealing material 5a and the back-side sealing material 5b are not particularly limited, but preferably have a property of transmitting light (translucency). The material of the light-receiving-side sealing material 5a preferably has an adhesive property for bonding the solar cell submodule 10 to the light-receiving-side protection member 3, and the material of the back-side sealing material 5b preferably has an adhesive property for bonding the solar cell submodule 10 to the back-side protection member 4. Examples of such materials include translucent 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, and silicone resin.

[0017] The light-receiving-side protection member 3 covers the surface (light-receiving surface, i.e., the surface on the transparent base material 12 side) of the solar cell submodule 10 via the light-receiving-side sealing material 5a to protect the solar cell submodule 10. The shape of the light-receiving-side protection member 3 is not particularly limited, but is preferably a plate or sheet shape in order to indirectly cover the planar light-receiving surface. The shape of the light-receiving-side protection member 3 may also be a curved shape.

[0018] The material of the light-receiving side protection member 3 is not particularly limited, but is preferably a material that has translucency and is resistant to ultraviolet light, similar to the light-receiving side sealing material 5a and the back-side sealing material 5b, and examples thereof include glass, or transparent resins such as acrylic resin or polycarbonate resin. The surface of the light-receiving side protection member 3 may be processed to have an uneven shape or may be coated with an anti-reflection coating layer. In this way, the light-receiving side protection member 3 makes it difficult to reflect the received light, so that more light can be guided to the solar cell submodule 10. In addition, when the material of the light-receiving side protection member 3 is a resin, a barrier film that prevents the passage of water vapor may be provided on the back or front surface of the light-receiving side protection member 3. This makes it possible to protect the solar cell submodule 10 from water vapor. In addition, when the material of the light-receiving side protection member 3 is a resin, the light-receiving side protection member 3 can be bent (flexed) and the light-receiving side protection member 3 can be made into a curved shape. This allows the solar cell module 100 to have a curved surface.

[0019] The back side protection member 4 covers the back side of the solar cell submodule 10 (i.e., the back side opposite to the transparent base material 12) via the back side sealing material 5b, thereby protecting the solar cell submodule 10. The shape of the back side protection member 4 is not particularly limited, but similar to the light-receiving side protection member 3, a plate or sheet shape is preferable in order to indirectly cover the planar back side.

[0020] The material of the back protection member 4 is not particularly limited, but is preferably a material that prevents the intrusion of water or the like (high water-proofing). Examples include resin films such as polyethylene terephthalate (PET), polyethylene (PE), olefin resin, fluorine-containing resin, or silicone-containing resin, or a laminate of a plate-shaped translucent resin member such as glass, polycarbonate, or acrylic and a metal foil such as aluminum foil. When the material of the back protection member 4 is resin, a barrier film that prevents the passage of water vapor may be provided on the front or back surface of the back protection member 4. This can protect the solar cell submodule 10 from water vapor.

[0021] A butyl rubber member 8 is disposed as an end sealing member on the peripheral edge of the solar cell module 100. In addition, a metal thin film 9 is disposed between the peripheral edge of the solar cell module 100 and the solar cell submodule 10. The butyl rubber member 8 and the metal thin film 9 will be described in detail later.

[0022] (Solar cell submodule) FIG. 4 is a schematic cross-sectional view of the solar cell submodule 10 in the solar cell module 100 shown in FIGS.

[0023] The solar cell submodule 10 is composed of thin-film solar cells such as inorganic semiconductor thin films, organic semiconductor thin films, or organic-inorganic hybrid semiconductor thin films, for example, amorphous silicon-based or perovskite-based. As shown in Fig. 4, the solar cell submodule 10 is composed of a plurality of thin-film solar cells 20 divided in the X direction (integration direction: first direction) on a transparent substrate 12, extending in the Y direction (second direction) intersecting the X direction, and integrated in series. This shortens the conductive distance in the X direction and reduces the amount of current per cell 20, and as a result, it is possible to reduce the resistance loss due to the electrodes 24, 25, particularly the electrodes 24, 25 made of transparent electrodes (ITO).

[0024] The substrate 12 is, for example, a flat plate or film substrate. Examples of materials for the substrate 12 include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), glass, and the like.

[0025] In the following, a solar cell submodule 10 including a perovskite solar cell as the thin-film solar cell 20 is illustrated. The solar cell 20 has a perovskite layer 21 as a photoelectric conversion layer, charge transport layers 22 and 23, and electrodes 24 and 25.

[0026] The perovskite layer 21 is a photoelectric conversion layer that absorbs light and generates photocarriers. The compound constituting the perovskite crystal material is represented by the general formula R 1 NH 3 M 1 X 3 or HC(NH 2 ) 2 M 1 X 3 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 is a divalent metal ion, preferably Pb or Sn. X is a halogen, such as F, Cl, Br, or I. All three Xs may be the same halogen element, or multiple halogens may be mixed.

[0027] A preferred example of a compound constituting a perovskite-type crystal material is a compound represented by the formula CH 3 NH 3 Pb(I 1-x Br x ) 3 (where 0≦x≦1). The spectral sensitivity characteristics of perovskite materials can be changed by changing the type and ratio of halogens. Perovskite thin films can be formed by various dry processes or solution film formation such as spin coating.

[0028] One of the charge transport layers 22 and 23 is a hole transport layer, and the other is an electron transport layer. 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.

[0029] Examples of materials for the electron transport layer include metal oxides such as titanium oxide, zinc oxide, niobium oxide, zirconium oxide, and aluminum oxide.

[0030] An electrode 24 for extracting photogenerated carriers is formed on the charge transport layer 22 side of the thin-film solar cell 20. An electrode 25 for extracting photogenerated carriers is formed on the charge transport layer 23 side of the thin-film solar cell 20.

[0031] The electrode 24 may include a transparent electrode and a metal electrode, or may include only a transparent electrode, or may include only a metal electrode. Similarly, the electrode 25 may include a transparent electrode and a metal electrode, or may include only a transparent electrode, or may include only a metal electrode. Metal oxides such as ITO, zinc oxide, and tin oxide are preferably used as materials for the transparent electrode. Silver, copper, aluminum, and the like are preferably used as materials for the metal electrode.

[0032] (Arrangement of butyl rubber material and thin metal film) 1 to 3, a butyl rubber member 8 is disposed as an end sealing member at the peripheral end of the solar cell module 100. The butyl rubber member 8 seals the periphery of the multiple thin-film solar cell submodules 10 and the periphery of the back-side sealing material 5b in a portion between the light-receiving-side protection member 3 and the back-side protection member 4, specifically, in the portion between the transparent base material 12 of the thin-film solar cell submodules 10 and the inner surface of the back-side protection member 4.

[0033] A metal thin film 9 is disposed at the peripheral edge of the solar cell module 100 and between the plurality of thin-film solar cell submodules 10. The metal thin film 9 is disposed between the thin-film solar cell submodule 10 and the light-receiving-side sealing material 5a, specifically, on the transparent base material 12 side of the thin-film solar cell submodule 10, around the plurality of thin-film solar cell submodules 10 so as to overlap with the butyl rubber member 8. The metal thin film 9 is disposed between the thin-film solar cell submodule 10 and the light-receiving-side sealing material 5a, specifically, on the transparent base material 12 side of the thin-film solar cell submodule 10, between the plurality of thin-film solar cell submodules 10 so as to straddle the transparent base material 12.

[0034] The surface of the thin metal film 9 may have an uneven structure, so that the thin metal film 9 functions as a light diffusing film and can diffusely reflect light incident on the thin metal film 9.

[0035] The material of the thin metal film 9 is not particularly limited, but examples thereof include Cu, Au, Ag, and Al.

[0036] Here, FIG. 5 is a schematic cross-sectional view of a solar cell module according to a first comparative example, and FIG. 6 is a schematic cross-sectional view of a solar cell module according to a second comparative example.

[0037] As in the solar cell module 100X of the first comparative example shown in Figure 5, when the peripheral edges of the solar cell module are sealed with butyl rubber member 8 throughout the entire area between the light-receiving-side protection member 3 and the back-side protection member 4, air bubbles are likely to form between the butyl rubber member 8 and the light-receiving-side protection member 3.

[0038] For example, when the solar cell submodule 10 is produced by a coating process, it is difficult to increase the area of ​​the solar cell submodule 10, so multiple solar cell submodules 10 are combined in a solar cell module. In this case, since the multiple solar cell submodules 10 cannot be exposed, the multiple solar cell submodules 10 are sealed with a light-receiving side protection member 3 and a back side protection member 4.

[0039] When, for example, a glass plate is used as the transparent base material 12 in the solar cell submodule 10, and when, for example, glass plates are used as the light-receiving side protection member 3 and the back side protection member 4, the solar cell module is composed of three glass plates. In this manner, in the three glass plate composition, there is a large unevenness (step) between the areas where the transparent base material 12 of the solar cell submodule 10 is present and the areas where it is not present. As a result, during thermal compression sealing of the solar cell module, the sealing material and butyl rubber do not adapt sufficiently to the uneven shape due to flow, and air bubbles are likely to occur between the butyl rubber member 8 and the light-receiving side protection member 3, leading to poor appearance and deterioration of the solar cell module. The air bubbles include vacuum bubbles and delamination (peeling that occurs after sealing) that occur during vacuum thermal compression sealing.

[0040] As in the solar cell module 100Y of the second comparative example shown in Figure 6, if the peripheral edges of the solar cell module and the spaces between the solar cell submodules 10 are sealed with butyl rubber member 8 between the transparent base material 12 of the solar cell submodule 10 and the inner surface of the back protection member 4, the butyl rubber member 8 is black, and therefore light incident on the butyl rubber member 8 cannot be used effectively.

[0041] In this regard, according to the solar cell module 100 of this embodiment, the butyl rubber member 8 seals the periphery of the thin-film solar cell submodules 10 and the periphery of the back-side sealing material 5b in a part between the light-receiving side protection member 3 and the back-side protection member 4, specifically, between the transparent base material 12 of the thin-film solar cell submodules 10 and the inner surface of the back-side protection member 4. In addition, the metal thin film 9 is disposed between the thin-film solar cell submodules 10 and the light-receiving side sealing material 5a, specifically, on the transparent base material 12 side of the thin-film solar cell submodules 10, around the periphery of the thin-film solar cell submodules 10 so as to overlap with the butyl rubber member 8. In addition, the metal thin film 9 is disposed between the thin-film solar cell submodules 10 and the light-receiving side sealing material 5a, specifically, on the transparent base material 12 side of the thin-film solar cell submodules 10, between the thin-film solar cell submodules 10, so as to straddle the transparent base material 12.

[0042] As a result, the back protection member 4, the transparent substrate 12 of the thin-film solar cell submodule 10, the butyl rubber member 8 and the metal thin film 9 seal the thin-film solar cell 20 of the thin-film solar cell submodule 10, blocking moisture from the outside.

[0043] The metal thin film 9 adheres more easily to the butyl rubber member 8 than the light-receiving-side protection member 3. This makes it possible to suppress air bubbles caused by insufficient adaptation to the uneven shape due to the flow of the sealing material and butyl rubber during thermal compression sealing of the solar cell module. In other words, it is possible to suppress the generation of air bubbles between the butyl rubber member and the protection member, and to suppress poor appearance and deterioration of the solar cell module 100.

[0044] Furthermore, the metal thin film 9 seals the peripheral edges of the solar cell module and the spaces between the solar cell submodules 10, thereby improving the effective use of light incident on the metal thin film 9. For example, light incident on the metal thin film 9 is reflected by the metal thin film 9, reflected by the light-receiving-side protection member 3, and re-enters the solar cell submodule 10. This improves the power generation efficiency of the solar cell module 100.

[0045] Furthermore, the surface of the thin metal film 9 has an uneven structure, and thus has a light diffusing function, which makes it possible to further increase the effective use of light incident on the thin metal film 9.

[0046] Although the embodiment of the present invention has been described above, the present invention is not limited to the above-described embodiment, and various changes and modifications are possible. [Explanation of symbols]

[0047] 3. Receiving side protection material 4 Back protection material 5a Receiving side encapsulant 5b Backside sealing material 8 Butyl rubber material 9 Metallic Thin Film 10 Thin-film solar cell submodules 12 Transparent base material 20 Thin-film solar cells 21 Photoelectric conversion layer 22,23 Charge transport layer 24,25 electrode 100 Solar Modules

Claims

1. A plurality of thin-film solar cell submodules each having a transparent substrate and a thin-film solar cell formed on the transparent substrate; a light-receiving side protection member disposed on the transparent base material side of the plurality of thin-film solar cell submodules; a light-receiving-side sealing material disposed between the plurality of thin-film solar cell submodules and the light-receiving-side protection member; a back protection member disposed on the opposite side of the transparent substrate of the plurality of thin-film solar cell submodules; a backside sealing material disposed between the thin-film solar cell submodules and the backside protection member; a butyl rubber member that seals the periphery of the thin-film solar cell submodules and the periphery of the back-side sealing material between the transparent base material and the back-side protection member of the thin-film solar cell submodules; a metal thin film arranged around the plurality of thin film solar cell submodules on the transparent base material side of the plurality of thin film solar cell submodules so as to overlap with the butyl rubber member; A solar cell module comprising:

2. The solar cell module according to claim 1 , wherein the metal thin film is further arranged between the plurality of thin-film solar cell submodules on the transparent substrate side of the plurality of thin-film solar cell submodules, so as to straddle the transparent substrate.

3. The solar cell module according to claim 1 , wherein the surface of the metal thin film has an uneven structure.

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