Solar cell module and method for manufacturing solar cell module

Abstract

A solar cell module (1) according to one embodiment of the present invention is provided with a substrate (2), a first electrode layer (11) provided on the substrate (2), a photoelectric conversion layer (10) provided on the first electrode layer (11), a second electrode layer (12) provided on the photoelectric conversion layer (10), an extraction electrode layer (20), and an encapsulation layer (30). The encapsulation layer (30) has an opening (30A) in a region corresponding to the extraction electrode layer (20). Furthermore, when the substrate (2) is viewed from the surface on which the photoelectric conversion layer (10) is provided, the extraction electrode layer (20) is exposed from the opening (30A), and the sealing layer (30) covers the peripheral edge portion of the extraction electrode layer (20).

Description

Technical Field

[0001] The present disclosure relates to a solar cell module and a method for manufacturing the same, and more particularly, to a solar cell module in which a photoelectric conversion layer is formed on an insulating substrate such as a glass substrate and a method for manufacturing the same. Background Art

[0002] Until now, solar cell modules in which a photoelectric conversion layer is formed on an insulating substrate such as a glass substrate have been known. Patent document 1 discloses a solar cell module comprising: a substrate, a plurality of solar cell units formed on the substrate, an extraction electrode formed on the substrate and extracting charges from the plurality of solar cell units, an extraction wiring material for collecting charges from the extraction electrode, a covering material covering the extraction wiring material, and a packaging material.

[0003] In addition, Patent Document 2 discloses a solar cell unit having: a cathode, an anode, a photoelectric conversion layer disposed between the cathode and the anode, and a resin layer disposed on either the cathode or the anode. Patent Document 2 states that: the photoelectric conversion layer comprises an organic-inorganic perovskite compound represented by the general formula RM-X3 (wherein R is an organic molecule, M is a metal atom, and X is a halogen atom or a sulfide atom.).

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Publication No. 2009-188211

[0007] Patent Document 2: Japanese Patent Application Publication No. 2016-174151 Summary of the invention

[0008] The output performance of the photoelectric conversion layer of the solar cell unit is greatly reduced due to the presence of water vapor, oxygen and light. Therefore, as described in Patent Documents 1 and 2, the photoelectric conversion layer is encapsulated in order to prevent water vapor and oxygen from acting on the photoelectric conversion layer. In particular, when the photoelectric conversion layer is a perovskite element, the output reduction caused by the influence of water vapor and oxygen is significant. In addition, as described in Patent Document 1, an electrode for taking out the power generated by the solar cell unit to the outside is provided in the solar cell module. The encapsulation performance is easily reduced around the electrode compared with other parts, so it can be assumed that water vapor and oxygen flow in from around the electrode.

[0009] An object of the present disclosure is to provide a solar cell module that can sufficiently suppress the inflow of water vapor and oxygen into the module and has excellent sealing performance.

[0010] The solar cell module disclosed in the present invention comprises: a substrate, a first electrode layer arranged on the substrate, a photoelectric conversion layer arranged on the first electrode layer, a second electrode layer arranged on the photoelectric conversion layer, an extraction electrode layer arranged in an area on the substrate that does not overlap with the photoelectric conversion layer when the substrate is viewed from above, and a packaging layer arranged in a manner covering the first electrode layer, the photoelectric conversion layer, the second electrode layer and the extraction electrode layer and having an opening in a area corresponding to the extraction electrode layer, when the substrate is viewed from a side on which the photoelectric conversion layer is provided, the extraction electrode layer is exposed from the opening, and the packaging layer covers the peripheral portion of the extraction electrode layer.

[0011] According to the solar cell module of the present disclosure, it is possible to sufficiently suppress water vapor and oxygen from flowing into the module. Since the solar cell module of the present disclosure has excellent sealing performance, it is possible to maintain good output performance for a long period of time, for example. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a cross-sectional view of the solar cell module according to the first embodiment.

[0013] Figure 2 It is a cross-sectional view of a solar cell module according to the second embodiment.

[0014] Figure 3 It is a cross-sectional view of a solar cell module according to a third embodiment.

[0015] Figure 4 This is a diagram for explaining an example of the method for manufacturing the solar cell module according to the first embodiment.

[0016] Figure 5 This is a diagram for explaining an example of a method for manufacturing a solar cell module according to the second embodiment.

[0017] Figure 6 This is a diagram for explaining an example of a method for manufacturing a solar cell module according to the third embodiment.

[0018] Figure 7 It is a cross-sectional view of a solar cell module according to a fourth embodiment.

[0019] Figure 8 It is a cross-sectional view of a solar cell module according to a fifth embodiment.

[0020] Fig. 9 It is a cross-sectional view of a solar cell module according to a sixth embodiment.

[0021] Fig.10 It is a cross-sectional view of a solar cell module according to the seventh embodiment. DETAILED DESCRIPTION

[0022] Hereinafter, an example of an embodiment of the solar cell module of the present disclosure will be described in detail with reference to the drawings. It should be noted that a form in which each component of the plurality of embodiments and modifications described below is selectively combined also falls within the scope of the present disclosure.

[0023] Figure 1 The cross-sectional structure of the solar cell module 1 according to the first embodiment cut along the X direction is schematically shown. It should be noted that the first direction along the surface of the substrate 2 is referred to as the “X direction ( Figure 1 The second direction along the surface of the substrate 2 and perpendicular to the X direction is denoted as the “Y direction ( Figure 1 in the direction perpendicular to the paper surface)". Figure 1 As shown, the solar cell module 1 includes a substrate 2 and a single cell 3 provided on the substrate 2. The single cell 3 is composed of a plurality of unit cells 4 connected in series. Each unit cell 4 includes a photoelectric conversion layer 10, a first electrode layer 11, and a second electrode layer 12.

[0024] The solar cell module 1 also includes an extraction electrode layer 20 and an encapsulation layer 30. The extraction electrode layer 20 is an electrode for extracting electric energy from the single cell 3 to the outside of the module, and is provided in a region that does not overlap with the photoelectric conversion layer 10 when the substrate 2 is viewed from above. The encapsulation layer 30 sandwiches the single cell 3 together with the substrate 2, and is a layer for inhibiting water vapor and oxygen from flowing into the module. The encapsulation layer 30 is provided in a manner that covers the single cell 3 (photoelectric conversion layer 10, first electrode layer 11, second electrode layer 12) and the extraction electrode layer 20, and has an opening 30A in a region corresponding to the extraction electrode layer 20.

[0025] The solar cell module 1 may include an inorganic film 40 provided on the substrate 2. The inorganic film 40 is interposed between the substrate 2 and the first electrode layer 11. The inorganic film 40 may be the same type of inorganic film as the barrier layer of the second layer 32 described later.

[0026] The details will be described later, but when the solar cell module 1 looks down at the substrate 2 from the side where the photoelectric conversion layer 10 is provided, the extraction electrode layer 20 is exposed from the opening 30A of the encapsulation layer 30, and the encapsulation layer 30 covers the peripheral portion of the extraction electrode layer 20. That is, on the surface 21 of the extraction electrode layer 20 facing the side opposite to the substrate 2, a portion thereof is exposed from the opening 30A of the encapsulation layer 30, and the surrounding of the exposed portion is covered by the encapsulation layer 30. In this case, it is possible to effectively suppress water vapor and oxygen from flowing into the module from the surrounding of the extraction electrode layer 20.

[0027] The substrate 2 can use a conductive substrate with an insulating layer formed on the surface, preferably an insulating substrate. The substrate 2 has, for example, permeability to sunlight with a wavelength of more than 400nm and less than 1000nm, and is composed of a material with low water vapor permeability. The substrate 2 can be a resin substrate or a glass substrate. The thickness of the substrate 2 is, for example, more than 0.02mm and less than 3mm. It should be noted that since the solar cell module 1 is provided with a support 5, a resin film similar to the barrier film described later can also be used as the substrate 2.

[0028] As described above, the solar cell module 1 includes a plurality of unit cells 4 connected in series. A plurality of unit cells 4 are arranged in the X direction and are continuous in the Y direction orthogonal to the X direction. The unit cell 4 of the present embodiment is a perovskite-type single cell, and includes a first electrode layer 11 provided on a substrate 2, a photoelectric conversion layer 10 provided on the first electrode layer 11, and a second electrode layer 12 provided on the photoelectric conversion layer 10. It should be noted that at least one of the substrate 2 and the encapsulation layer 30 covering the surface of the single cell 3 (each unit cell 4) is light-transmissive. In this case, light is incident into the module from one side of the substrate 2, one side of the encapsulation layer 30, or both sides, and is absorbed by the photoelectric conversion layer 10 of each unit cell 4. In the present embodiment, the encapsulation layer 30 is opaque, and the surface of the substrate 2 constitutes the light-receiving surface of the module.

[0029] The photoelectric conversion layer 10 includes a light absorbing layer 13, an electron transport layer 14, and a hole transport layer 15, and has a stacked structure in which the electron transport layer 14 and the hole transport layer 15 are arranged in a manner of sandwiching the light absorbing layer 13 from both sides. In the photoelectric conversion layer 10 of this embodiment, except for the portion where the groove described later is formed, the electron transport layer 14, the light absorbing layer 13, and the hole transport layer 15 are sequentially arranged from the substrate 2 side. The light absorbing layer 22, for example, includes a perovskite compound represented by the composition formula ABX3 (wherein A is a monovalent cation, B is a divalent cation, and X is a halogen anion).

[0030] The electron transport layer 14 is composed of an n-type semiconductor and is also referred to as an n-layer. Examples of electron transport materials constituting the electron transport layer 14 include anatase-type titanium oxide, tin oxide, and the like. The hole transport layer 15 is composed of a p-type semiconductor and is also referred to as a p-layer. The hole transport layer 15 includes a hole transport material having a redox site. Examples of hole transport materials constituting the hole transport layer 15 include 2,2',7,7'-tetrakis(N,N'-di-p-methoxyphenylamino)-9,9'-spirobifluorene (Spiro-OMeTAD) and the like.

[0031] An example of A in the above-mentioned perovskite compound (ABX3) is a monovalent cation represented by R1R2R3-NH. When R1 and R2 are H and R3 is CH3, A is methylammonium (CH3NH3). The functional groups R1, R2, and R3, for example, contain at least one element selected from carbon, hydrogen, nitrogen, and oxygen. When the functional groups R1, R2, and R3 contain carbon atoms, the sum of the carbon numbers of the functional groups R1, R2, and R3 is preferably 4 or less. The functional groups R1, R2, and R3 may contain Group 1 elements such as Rb and Cs.

[0032] As described above, B of ABX3 is a divalent cation. B is, for example, a divalent cation of a transition metal or a Group 13 element, a Group 14 element, or a Group 15 element. Specific examples of B include Pb 2+ ,Ge 2+ Sn 2+ B may include a compound selected from Pb 2+ and Sn 2+ At least one of the following, some Pb 2+ Sn 2+ It may be substituted by other elements. Examples of the substituent element include Bi, Sb, In, Ge, Ni, etc. X in ABX3 is at least one selected from Cl, Br, and I.

[0033] The sites of A, M, and X can be occupied by a variety of ions. Specific examples of perovskite compounds (ABX3) include CH3NH3PbI3, CH3CH2NH3PbI3, NH2CHNH2PbI3, CH3NH3PbBr3, CH3NH3PbCl3, CsPbI3, and CsPbBr3. The light absorbing layer 13 composed of CH3NH3PbI3 is also called a PVSK element.

[0034] The first electrode layer 11 and the second electrode layer 12 are preferably light-transmissive and do not block light from entering the photoelectric conversion layer 10. The light transmittance of each electrode layer is, for example, 85% or more in the range of wavelengths above 450 nm and below 900 nm. In addition, the sheet resistance of each electrode layer is preferably below 200 Ω / □, and can be below 50 Ω / □. An example of a suitable electrode layer is a transparent conductive layer composed of a transparent conductive oxide such as indium tin oxide (ITO) doped with tungsten, tin, antimony, etc. in a metal oxide such as indium oxide or zinc oxide. The thickness of the transparent conductive layer is, for example, above 30 nm and below 300 nm. Each electrode layer can be formed into a film by existing well-known methods such as sputtering.

[0035] Figure 12 adjacent unit cells 4 in the X direction are shown, the unit cell 4 on the left is referred to as “unit cell 4A”, and the unit cell 4 on the right is referred to as “unit cell 4B”. The number of unit cells 4 included in the solar cell module 1 is not particularly limited, and may be three or more. Figure 1 In the example shown, the second electrode layer 12 of the unit cell 4A is electrically connected to the first electrode layer 11 of the unit cell 4B. In the case of including three or more unit cells 4, for example, the second electrode layer 12 of the unit cell 4B is electrically connected to the first electrode layer 11 of the third unit cell 4 adjacent in the X direction. In this way, the plurality of unit cells 4 are connected in series along the X direction.

[0036] The cell 3 is formed with grooves 16, 17, and 18. The grooves 16, 17, and 18 are formed by removing a portion of the layer constituting the cell 3, and are formed substantially parallel to each other along the Y direction. Each groove can be formed by a conventionally known scribing method or the like. The width of each groove is, for example, not less than 30 μm and not more than 300 μm. The groove 17 is filled with a resin constituting the encapsulation layer 30 in a manner that does not form a void in the groove.

[0037] The groove 16 is a groove for dividing the first electrode layer 11 of each unit cell 4. The groove 17 divides the light absorption layer 13, the hole transport layer 15, and the second electrode layer 12 of each unit cell 4. It should be noted that the groove 17 only needs to divide the second electrode layer 12 of each unit cell 4, and the light absorption layer 13 and the hole transport layer 15 may not be divided by the groove 17. In this embodiment, each unit cell 4 is divided by the grooves 16 and 17.

[0038] The groove 18 is formed so as to penetrate the hole transport layer 15, the light absorption layer 13, and the electron transport layer 14 and expose the first electrode layer 11 of the unit cell 4B. In addition, the second electrode layer 12 of the unit cell 4A is formed in the groove 18. Thus, the first electrode layer 11 of the unit cell 4B is electrically connected to the second electrode layer 12 of the unit cell 4A. That is, the groove 18 functions as a conductive path that connects the plurality of unit cells 4 in series.

[0039] The single cell 3 is manufactured, for example, by the following method.

[0040] (1) The first electrode layer 11 and the electron transport layer 14 are formed in this order on the substrate 2 .

[0041] (2) Laser scribing is performed on a portion of the first electrode layer 11 to form the groove 16 .

[0042] (3) The light absorbing layer 13 and the hole transporting layer 15 are sequentially formed on the electron transporting layer 14 .

[0043] (4) Mechanical scribing is performed on a portion of the hole transport layer 15 , the light absorption layer 13 , and the electron transport layer 14 to form the grooves 18 .

[0044] (5) The second electrode layer 12 is formed on the hole transport layer 15. At this time, the second electrode layer 12 is formed in the groove 18 to form the above-mentioned conductive path.

[0045] (6) The second electrode layer 12 , the hole transport layer 15 , and a portion of the light absorbing layer 13 are subjected to mechanical scribing to form the grooves 17 .

[0046] The light absorbing layer 13, the electron transport layer 14 and the hole transport layer 15 can be formed, for example, by applying a solution in which the constituent materials of each layer are dissolved on the surface of the substrate 2. These layers can be formed by a meniscus coating method, a spin coating method or a dispenser. The thickness of each layer is not particularly limited, and as an example, is 10 nm or more and 500 nm or less.

[0047] Hereinafter, the configurations of the extraction electrode layer 20 and the encapsulation layer 30 will be described in detail.

[0048] The extraction electrode layer 20 has a structure in which metal layers are stacked, and is provided on the substrate 2 in a region that does not overlap with the photoelectric conversion layer 10 when the substrate 2 is viewed from above. In other words, the extraction electrode layer 20 is provided in a region that does not overlap with the photoelectric conversion layer 10 in the thickness direction of the solar cell module 1. The extraction electrode layer 20 includes an extraction electrode layer 20A electrically connected to the first electrode layer 11 of the unit cell 4A, and an extraction electrode layer 20B electrically connected to the second electrode layer 12 of the unit cell 4B. The extraction electrode layer 20A is arranged at the first end portion in the X direction of the substrate 2, and the extraction electrode layer 20B is arranged at the second end portion in the X direction on the opposite side of the first end portion.

[0049] The metal layer constituting the extraction electrode layer 20 is composed of, for example, a metal such as aluminum, nickel, copper, silver, or an alloy thereof. Among them, silver is preferably used. The metal layer may be a single-layer structure or a multilayer structure including a heterogeneous metal layer. An example of the thickness of the extraction electrode layer 20 is greater than 10 μm and less than 100 μm. The extraction electrode layer 20 may be formed by printing, sputtering, evaporation, etc., or may be formed by a plating method.

[0050] The encapsulation layer 30 is a layer that covers the entire single cell 3 and inhibits water vapor and oxygen from flowing into the module. In addition, the encapsulation layer 30 may have a function of capturing water vapor, etc. The encapsulation layer 30 covers the side surface of the extraction electrode layer 20 along the thickness direction. On the other hand, since the extraction electrode layer 20 is an electrode for extracting the power generated by the single cell 3 to the outside of the module, a portion of the surface 21 of the extraction electrode layer 20 facing the opposite side of the substrate 2 is not covered by the encapsulation layer 30 and is exposed. The encapsulation layer 30 is formed with an opening 30A that exposes a portion of the surface 21 of the extraction electrode layer 20.

[0051] The encapsulation layer 30 covers the peripheral portion of the surface 21 of the extraction electrode layer 20 when the substrate 2 is viewed from the side where the photoelectric conversion layer 10 is provided. The shape of the opening 30A of the encapsulation layer 30 is not particularly limited, and as an example, it is a circular shape when viewed from above. The opening 30A of the encapsulation layer 30 is configured in a manner that does not overlap with the surface 21 of the extraction electrode layer 20 in the thickness direction of the module, and the portion where the opening area is minimized is smaller than the surface 21. In the present embodiment, the area of ​​the opening 30A is minimized in the portion in contact with the surface 21.

[0052] The encapsulation layer 30 may have a single-layer structure or a multi-layer structure having three or more layers. In this embodiment, it has a two-layer structure including a first layer 31 and a second layer 32. The first layer 31 has a first opening 31A in a region corresponding to the extraction electrode layer 20. The second layer 32 is provided in a manner covering the first layer 31 and has a second opening 32A in a region corresponding to the extraction electrode layer 20. The details will be described later. The first opening 31A and the second opening 32A are overlapped in the thickness direction of the module to form an opening 30A of the encapsulation layer 30.

[0053] The first layer 31 is filled in the groove 17 formed in the single cell 3, between the single cell 3 and the extraction electrode layer 20, etc., and is in close contact with the single cell 3 and the extraction electrode layer 20. The first layer 31 is preferably in close contact with the single cell 3 without forming a gap between the single cell 3. In this case, it is possible to suppress the inflow of water vapor and oxygen into the module. The first layer 31 is preferably composed of a resin with low water vapor and oxygen permeability. The first layer 31 may contain a hygroscopic filler. The first layer 31 having the function of capturing moisture is also called a getter layer.

[0054] The resin constituting the first layer 31 may be a resin having low water vapor and oxygen permeability and good adhesion to the single cell 3. As an example of a suitable resin, an olefin polymer may be cited. An olefin polymer is a polymer having units derived from olefins as main structural units. The first layer 31 is, for example, a layer in which a hygroscopic filler is dispersed in an olefin polymer. It should be noted that the first layer 31 may contain other components besides the olefin polymer and the hygroscopic filler. As other components, a tackifier, a curing accelerator, an antioxidant, a plasticizer, a rubber component, etc. may be cited.

[0055] The olefin polymer is preferably a copolymer of two or more olefins, a copolymer of an olefin and a monomer other than an olefin such as a non-conjugated diene, styrene, etc. As an example of a copolymer, ethylene-non-conjugated diene copolymers, ethylene-propylene copolymers, ethylene-propylene-non-conjugated diene copolymers, ethylene-butene copolymers, propylene-butene copolymers, propylene-butene-non-conjugated diene copolymers, styrene-isobutylene copolymers, styrene-isobutylene-styrene copolymers, isobutylene-isoprene copolymers, etc. can be listed.

[0056] The olefin polymer preferably has a crosslinked structure, and is obtained by reacting a copolymer containing a first reactive functional group with a copolymer containing a second reactive functional group. The reactive functional group can be selected from the group consisting of an epoxy group, a carboxyl group, an anhydride group, an amino group, a hydroxyl group, and an isocyanate group, and is used in a combination that reacts with each other. Specific examples of the combination of reactive functional groups include an epoxy group and a carboxyl group, an epoxy group and an anhydride group, a carboxyl group and an anhydride group, and the like.

[0057] Examples of the hygroscopic filler include uncalcined hydrotalcite, semi-calcined hydrotalcite, calcined hydrotalcite, calcium oxide, magnesium oxide, calcined dolomite, calcium hydride, strontium oxide, aluminum oxide, barium oxide, molecular sieves, and silicon dioxide.

[0058] The thickness of the first layer 31 is, for example, not less than 10 μm and not more than 100 μm, preferably not less than 30 μm and not more than 70 μm. If the thickness of the first layer 31 is within this range, good encapsulation performance and water vapor capture performance can be ensured. The material constituting the first layer 31 is supplied in a thin film form during the manufacturing process of the solar cell module 1, and flows and fits tightly with the single cell 3 without a gap by heating, pressurizing, or heating and pressurizing, and is also filled into the groove of the single cell 3.

[0059] The second layer 32 is a layer with low water vapor and oxygen permeability, and is provided in a manner to cover the entire first layer 31, thereby inhibiting water vapor and oxygen from flowing into the module. The second layer 32 is preferably composed of a resin film having a barrier layer. The resin film is composed of, for example, olefin polymers such as polyethylene, polypropylene, and polyvinyl chloride, polyesters such as polyethylene terephthalate, polycarbonate, polyimide and other resins as main components. The barrier layer is preferably formed on the inner surface of the resin film, that is, the surface facing the first layer 31 side. As an example of a barrier layer, inorganic films such as silicon dioxide vapor-deposited films, silicon nitride films, and silicon oxide films can be listed.

[0060] The thickness of the second layer 32 is, for example, 20 μm or more and 150 μm or less, and preferably 50 μm or more and 100 μm or less. It should be noted that since the thickness of the barrier layer is thinner than that of the resin film, the thickness of the second layer 32 is substantially the same as the thickness of the resin film constituting the second layer 32. The relationship between the thickness of the first layer 31 and the second layer 32 is not particularly limited.

[0061] As described above, the first layer 31 and the second layer 32 are stacked in sequence from the substrate 2 side, and are arranged in a manner that the first opening 31A overlaps the second opening 32A. Regarding the extraction electrode layer 20, a portion of its surface 21 is exposed from the opening 30A (the first opening 31A and the second opening 32A) of the encapsulation layer 30, and the surface 21 is located closer to the substrate 2 side than the surface of the encapsulation layer 30, and is buried in the encapsulation layer 30. In this embodiment, the surface 21 of the extraction electrode layer 20 is located closer to the substrate 2 side than the interface between the first layer 31 and the second layer 32.

[0062] The first layer 31 preferably covers the peripheral portion of the surface 21 of the extraction electrode layer 20 and is in close contact with the side surface along the thickness direction of the extraction electrode layer 20. In this case, it is possible to more effectively suppress the inflow of water vapor and oxygen into the module. In this embodiment, the first opening 31A of the first layer 31 is formed to be smaller than the second opening 32A of the second layer 32. The opening 30A of the encapsulation layer 30 formed by the first opening 31A and the second opening 32A can be gradually reduced as it approaches the surface 21 of the extraction electrode layer 20. Figure 1 In the example shown, the first opening 31A gradually decreases in diameter toward the surface 21 .

[0063] The first layer 31 preferably covers the entire area of ​​the peripheral portion of the surface 21. That is, the first layer 31 is in close contact with the surface 21 in the entire circle of the peripheral portion of the surface 21 in a manner that surrounds the portion exposed from the first opening 31A of the surface 21. In this case, the effect of suppressing the influx of water vapor and oxygen is more significant. The first layer 31 can be configured in a circle with a substantially constant width from the periphery of the surface 21. The first layer 31, for example, covers an area of ​​more than 10% and less than 50% of the area of ​​the surface 21. In the present embodiment, the second opening 32A of the second layer 32 is formed to a size larger than the surface 21.

[0064] Figure 2 is a cross-sectional view of a solar cell module 1X according to a second embodiment. Figure 3 It is a cross-sectional view of a solar cell module 1Y according to the third embodiment.

[0065] like Figure 2 and Figure 3 As shown, the solar cell modules 1X and 1Y are similar to the solar cell module 1 in that the encapsulation layer 30 has a two-layer structure including the first layer 31 and the second layer 32, and the surface 21 of the extraction electrode layer 20 is located closer to the substrate 2 than the interface between the first layer 31 and the second layer 32. That is, the extraction electrode layer 20 is buried in the first layer 31. In this case as well, when the substrate 2 is viewed from the side where the photoelectric conversion layer 10 is provided, a portion of the surface 21 of the extraction electrode layer 20 is exposed from the first opening 31A and the second opening 32A.

[0066] On the other hand, the solar cell modules 1X and 1Y are different from the solar cell module 1 in that the second opening 32A of the second layer 32 is formed smaller than the first opening 31A of the first layer 31. In other words, the first opening 31A is larger than the second opening 32A. In this case, the opening area of ​​the outermost surface of the solar cell module 1 becomes smaller, so the amount of water vapor and oxygen flowing into the opening can be reduced.

[0067] Figure 2 In the solar cell module 1X shown, the second opening 32A of the second layer 32 is formed to be smaller than the area of ​​the surface 21 of the extraction electrode layer 20. In addition, the second layer 32 is arranged on the peripheral portion in a manner to completely cover the peripheral portion of the surface 21. It should be noted that since the first layer 31 is sandwiched between the extraction electrode layer 20 and the second layer 32, the second layer 32 does not contact the surface 21. The opening area of ​​the second opening 32A is preferably small within a range that does not affect the extraction of power from the extraction electrode layer 20, and as an example, is less than 90% of the area of ​​the surface 21. In the solar cell module 1X, the first opening 31A of the first layer 31 is formed to be larger than the surface 21, and the peripheral portion of the surface 21 is not covered by the first layer 31.

[0068] about Figure 3The solar cell module 1Y shown is also similar to the solar cell module 1X in that the second opening 32A of the second layer 32 is formed smaller than the area of ​​the surface 21 of the extraction electrode layer 20, and the second layer 32 is arranged on the peripheral portion of the surface 21. On the other hand, the solar cell module 1Y is different from the solar cell module 1X in that the first opening 31A of the first layer 31 is formed smaller than the area of ​​the surface 21, and the peripheral portion of the surface 21 is covered by the first layer 31. That is, the surface 21> the first opening 31A> the second opening 32A is formed, and the peripheral portion of the surface 21 is covered by the first layer 31 and the second layer 32. In this case, the effect of suppressing the inflow of water vapor and oxygen is more significant.

[0069] Below, refer to Figures 4 to 6 , an example of a method for manufacturing the solar cell modules 1, 1X, 1Y having the above-mentioned structure will be described in detail. Figures 4 to 6 The cross-sectional structure of a solar cell module in the manufacturing process cut along the X direction is shown.

[0070] The manufacturing process of the solar cell modules 1 , 1X, and 1Y includes the following steps, for example.

[0071] (1) Step of sequentially providing the first electrode layer 11, the photoelectric conversion layer 10, and the second electrode layer 12 on the substrate 2

[0072] (2) A step of providing the extraction electrode layer 20 on the substrate 2 in a region that does not overlap with the photoelectric conversion layer 10 when the substrate 2 is viewed from above.

[0073] (3) Step of providing the encapsulation layer 30 on the second electrode layer 12 and the extraction electrode layer 20

[0074] As described above, the photoelectric conversion layer 10 , the first electrode layer 11 , the second electrode layer 12 , and the extraction electrode layer 20 can be provided on the substrate 2 by a conventionally known method.

[0075] Figures 4 to 6 The diagrams show the process of providing the encapsulation layer 30 , and each diagram shows a different formation method. Figures 4 to 6 In the example shown, a support 5 for supporting the substrate 2 is used. The support 5 may be a member having a greater thickness than the substrate 2 and a higher rigidity. The solar cell module is carried, for example, in a state of being mounted on the support 5, and each layer is formed on the substrate 2. By using the support 5, stable mass production of solar cell modules becomes possible. An adhesive layer for bonding may be provided between the support 5 and the substrate 2.

[0076] Figure 4 The manufacturing process of the solar cell module 1 is shown. Figure 4In the example shown, after the encapsulation layer 30 is disposed on the second electrode layer 12 and the extraction electrode layer 20, a portion of the encapsulation layer 30 is removed to form an opening 30A. The opening 30A is formed in a region of the encapsulation layer 30 corresponding to the extraction electrode layer 20, that is, in a position overlapping with the extraction electrode layer 20 in the thickness direction of the module, by a conventionally known scribing method or the like. The opening 30A is formed in such a manner that the extraction electrode layer 20 is exposed through the opening 30A when the substrate 2 is viewed from the side where the photoelectric conversion layer 10 is provided, and the peripheral portion of the extraction electrode layer 20 is covered by the encapsulation layer 30.

[0077] Figure 4 In the example shown, the thin film 31F constituting the first layer 31 is arranged so as to cover the second electrode layer 12 and the extraction electrode layer 20, and the thin film 32F constituting the second layer 32 is further arranged thereon. The thin films 31F and 32F may be integrated in advance and then supplied to the substrate 2. The thin film 31F disposed on the substrate 2 is heated, pressurized, or heated and pressurized so that the thin film 31F is closely attached to the single cell 3 and the like. At this time, the material constituting the first layer 31 is also filled into the groove 17.

[0078] Figure 4 In the example shown, the opening 30A of the encapsulation layer 30 (the first opening 31A of the first layer 31) is formed so that the opening area gradually decreases as it approaches the surface 21 of the extraction electrode layer 20. The first layer 31 completely covers the peripheral portion of the surface 21, but the openings may be formed in each of the thin films 31F and 32F so that both the first layer 31 and the second layer 32 cover the peripheral portion of the surface 21. That is, each opening may be formed so that both the first opening 31A and the second opening 32A are smaller than the area of ​​the surface 21.

[0079] Figure 5 The manufacturing process of the solar cell module 1X is shown. Figure 5 In the example shown, a sealing layer 30 having an opening 30A is disposed on the second electrode layer 12 and the extraction electrode layer 20. In this case, the sealing layer 30 is disposed in such a manner that the extraction electrode layer 20 is exposed by the opening 30A when the substrate 2 is viewed from the side where the photoelectric conversion layer 10 is provided, and the peripheral portion of the extraction electrode layer 20 is covered. That is, in this manufacturing process, thin films 31F and 32F having openings formed in advance are disposed on the substrate 2. More specifically, the thin films 31F and 32F are disposed in such a manner that the extraction electrode layer 20, the first opening 31A, and the second opening 32A overlap in the thickness direction of the module.

[0080] Figure 5 Although the manufacturing process of the solar cell module 1X is shown, the solar cell modules 1 and 1Y can also be manufactured in the same manner. Figure 5In the example shown, the second opening 32A of the second layer 32 is formed to be smaller than the first opening 31A of the first layer 31, so that the surface 21 of the extraction electrode layer 20 ≥ the first opening 31A> the second opening 32A, and the solar cell modules 1, 1Y can be manufactured by changing the size of each opening.

[0081] Figure 6 Although the manufacturing process of the solar cell module 1Y is shown, the solar cell module 1X can also be manufactured in the same manner. Figure 6 In the example shown, the first layer 31 having the first opening 31A formed in advance is provided on the second electrode layer 12 and the extraction electrode layer 20, and the second opening 32A is formed after the second layer 32 is provided on the first layer 31. That is, the manufacturing process includes a step of providing the first layer 31 having the first opening 31A in a region corresponding to the extraction electrode layer 20, a step of providing the second layer 32 on the first layer 31, and a step of removing a portion of the second layer 32 to form the second opening 32A.

[0082] Figure 6 In the example shown, the first layer 31 and the second layer 32 are provided so that the extraction electrode layer 20 is exposed through the first opening 31A and the second opening 32A when the substrate 2 is viewed from the side provided with the photoelectric conversion layer 10, and the peripheral portion of the extraction electrode layer 20 is covered by at least one of the first layer 31 and the second layer 32, thereby forming the second opening 32A. In this manufacturing process, the thin film 31F is arranged so that the extraction electrode layer 20 overlaps with the first opening 31A in the thickness direction of the module, and after the thin film 32F is stacked on the thin film 31F, the second opening 32A is formed at a position overlapping with the first opening 31A.

[0083] Below, refer to Figure 7 to Figure 10 , and other embodiments of the solar cell module are described. The following describes the differences from the above-mentioned embodiment.

[0084] Figure 7 to Figure 9 The fourth to sixth embodiments illustrated in the figure are similar to the above-mentioned embodiments, in that the surface 21 of the extraction electrode layer 20 is located closer to the substrate 2 than the surface of the encapsulation layer 30, and is buried in the encapsulation layer 30. In addition, the surface 21 of the extraction electrode layer 20 is exposed from the opening 30A of the encapsulation layer 30. On the other hand, the surface 21 of the extraction electrode layer 20 is not covered by the first layer 31 and the second layer 32. However, the configurations of the first to third embodiments described above can be selectively applied in the fourth to sixth embodiments. In this case, the effect of suppressing the inflow of water vapor and oxygen is more significant.

[0085] like Figure 7As shown, in the solar cell module 50 of the fourth embodiment, the groove 17 for filling the first layer 31 of the encapsulation layer 30 is formed in a manner that gradually widens as it moves away from the substrate 2. The groove 17 is formed, for example, by removing a portion of the photoelectric conversion layer 10, the hole transport layer 15, and the second electrode layer 12 (the portion overlapping in the thickness direction of the module), and the opening formed in the hole transport layer 15 is larger than the opening formed in the photoelectric conversion layer 10. Furthermore, the opening of the second electrode layer 12 is larger than the opening of the hole transport layer 15.

[0086] In the solar cell module 50, as described above, the groove 17 is formed so as to gradually widen as it moves away from the substrate 2, and the first layer 31 is formed in the groove 17. The groove 17 may be formed as follows. Figure 7 The width shown may change stepwise at the interface of each layer, or may be continuously widened from the photoelectric conversion layer 10 toward the second electrode layer 12. By having such a groove 17, it is easy to fill the groove with the constituent material of the first layer 31, and it is difficult to form a gap in the groove. As a result, it is possible to effectively suppress the inflow of water vapor and oxygen into the module.

[0087] like Figure 8 As shown, in the solar cell module 51 of the fifth embodiment, fine concavo-convex is formed on the surface of the second electrode layer 12 in contact with the first layer 31 of the encapsulation layer 30. In this case, the contact area between the first layer 31 and the second electrode layer 12 is increased, and the adhesion between the first layer 31 and the second electrode layer 12 is improved. As a result, it is difficult to generate a gap between the first layer 31 and the second electrode layer 12, and the inflow of water vapor and oxygen into the module can be effectively suppressed. The concavo-convex can be formed only on the surface of the second electrode layer 12, and Figure 8 In the example shown, the surface of the photoelectric conversion layer 10 is provided with irregularities, and the hole transport layer 15 and the second electrode layer 12 are formed along the irregularities of the photoelectric conversion layer 10 , thereby providing irregularities on the surface of the second electrode layer 12 .

[0088] The arithmetic mean roughness Ra of the surface of the second electrode layer 12 is, for example, 1 nm or more and 100 nm or less. If the arithmetic mean roughness Ra is within this range, the improvement effect of the adhesion between the first layer 31 and the second electrode layer 12 is more significant. The arithmetic mean roughness Ra of the surface of the second electrode layer 12 can be measured by cross-sectional TEM. The method for forming the concavoconvex on the surface of the photoelectric conversion layer 10 is not particularly limited, and as an example, a spin coating method can be cited.

[0089] like Fig. 9As shown, the solar cell module 52 of the sixth embodiment includes a spring electrode 60 as a wiring material electrically connected to the extraction electrode layer 20. The spring electrode 60 is arranged in the opening 30A of the encapsulation layer 30, and one axial end portion is in contact with the surface 21 of the extraction electrode layer 20. The other axial end portion of the spring electrode 60 extends from the opening 30A and is connected to an external device not shown. The opening 30A can be filled with an encapsulation material 61 for sealing the gap between the encapsulation layer 30 and the spring electrode 60. For example, the encapsulation material 61 can use the same material as the constituent material of the first layer 31.

[0090] like Fig.10 As shown, in the solar cell module 53 of the seventh embodiment, the thickness of the first layer 31 constituting the encapsulation layer 30 becomes smaller around the extraction electrode layer 20. By forming the extraction electrode layer 20 to be thicker than the encapsulation layer 30 and increasing the opening of the thin film constituting the first layer 31 to the extent that a gap is formed between the extraction electrode layer 20, the thin film is filled in the gap and collapsed toward the substrate 2 side. Then, around the extraction electrode layer 20, the second layer 32 follows the first layer 31, forming a state in which the surface of the second layer 32 is concave. Therefore, the surface 21 of the extraction electrode layer 20 and its vicinity protrude from the encapsulation layer 30.

[0091] According to the solar cell module 53, the sealing layer 30 is firmly adhered to the side surface of the extraction electrode layer 20, and a gap is not easily formed between the extraction electrode layer 20 and the sealing layer 30. As a result, it is possible to effectively suppress the inflow of water vapor and oxygen into the module.

[0092] As described above, according to the solar cell modules of the above-mentioned embodiments, it is possible to fully suppress water vapor and oxygen from flowing into the module. The solar cell modules of the above-mentioned embodiments are excellent in encapsulation performance, and thus can maintain good output performance for a long time. In particular, as in the solar cell modules 1, 1X, and 1Y of the first to third embodiments, when the peripheral portion of the extraction electrode layer 20 is covered by the encapsulation layer 30 when looking down at the substrate 2 from the side where the photoelectric conversion layer 10 is provided, it is possible to effectively suppress water vapor and oxygen from flowing into the module from the periphery of the extraction electrode layer 20.

[0093] It should be noted that the above-mentioned embodiments can be appropriately modified in design within the scope that does not impair the purpose of the present disclosure. As described above, the configurations of the first to third embodiments can be selectively applied in the fourth to sixth embodiments, in which case the effect of suppressing the inflow of water vapor and oxygen is more significant. In other words, at least one configuration selected from the group consisting of the widened shape of the groove 17 of the fourth embodiment, the surface unevenness of the second electrode layer 12 of the fifth embodiment, and the spring electrode 60 of the sixth embodiment can be applied to the solar cell modules 1, 1X, and 1Y.

[0094] In addition, the encapsulation layer can be supplied to the manufacturing process of the solar cell module in the form of a single film including the barrier layer as an intermediate layer. The barrier layer is, for example, sandwiched by two resin films. The resin film disposed on the substrate 2 can be a film having the same function as the film constituting the first layer 31, and the resin film disposed outside the barrier layer can be a film having the same function as the film constituting the second layer 32.

[0095] Explanation of symbols

[0096] 1, 1X, 1Y, 50, 51, 52, 53 solar cell module, 2 substrate, 3 single cell, 4, 4A, 4B unit cell, 5 support, 10 photoelectric conversion layer, 11 first electrode layer, 12 second electrode layer, 13 light absorption layer, 14 electron transport layer, 15 hole transport layer, 16, 17, 18 groove, 20, 21, 20B extraction electrode layer, 21 surface, 30 packaging layer, 30A opening, 31 first layer, 31A first opening, 32 second layer, 32A second opening, 40 inorganic film, 60 spring electrode, 61 packaging material

Claims

1. A solar cell module comprising: Base material, a first electrode layer disposed on the substrate, a photoelectric conversion layer disposed on the first electrode layer, a second electrode layer disposed on the photoelectric conversion layer, an extraction electrode layer provided on the substrate in a region not overlapping with the photoelectric conversion layer when the substrate is viewed from above, and a sealing layer provided so as to cover the first electrode layer, the photoelectric conversion layer, the second electrode layer and the extraction electrode layer and having an opening in a region corresponding to the extraction electrode layer, When the substrate is viewed from the side where the photoelectric conversion layer is provided, the extraction electrode layer is exposed from the opening, and the encapsulation layer covers the peripheral edge of the extraction electrode layer.

2. The solar cell module according to claim 1, wherein: The encapsulation layer includes: a first layer having a first opening in a region corresponding to the extraction electrode layer, and a second layer provided to cover the first layer and having a second opening in a region corresponding to the extraction electrode layer. When the substrate is viewed from the side where the photoelectric conversion layer is provided, the extraction electrode layer is exposed from the first opening and the second opening. The second opening is formed to be smaller than the first opening.

3. The solar cell module according to claim 2, wherein: When the substrate is viewed in plan from the side where the photoelectric conversion layer is provided, the first layer and the second layer cover the peripheral edge of the extraction electrode layer.

4. The solar cell module according to any one of claims 1 to 3, wherein: The photoelectric conversion layer comprises a light absorbing layer, an electron transporting layer, and a hole transporting layer. The light absorbing layer includes a perovskite compound.

5. A method for manufacturing a solar cell module, comprising the following steps: The step of sequentially providing a first electrode layer, a photoelectric conversion layer and a second electrode layer on a substrate; A step of providing a extraction electrode layer on the substrate in a region that does not overlap with the photoelectric conversion layer when the substrate is viewed from above; and A step of providing a sealing layer having an opening on the second electrode layer and the extraction electrode layer; The encapsulating layer is provided so that the extraction electrode is exposed through the opening when the substrate is viewed from the side where the photoelectric conversion layer is provided, and covers the peripheral edge of the extraction electrode layer.

6. A method for manufacturing a solar cell module, comprising the following steps: The step of sequentially providing a first electrode layer, a photoelectric conversion layer and a second electrode layer on a substrate; A step of providing a lead-out electrode layer on the substrate in a region that does not overlap with the photoelectric conversion layer when the substrate is viewed from above; a step of providing a sealing layer on the second electrode layer and the extraction electrode layer; and a step of removing a portion of the encapsulation layer to form an opening, The opening is formed in the encapsulating layer so that the extraction electrode is exposed through the opening when the substrate is viewed from a side where the photoelectric conversion layer is provided, and the periphery of the extraction electrode layer is covered by the encapsulating layer.

7. A method for manufacturing a solar cell module, comprising the following steps: The step of sequentially providing a first electrode layer, a photoelectric conversion layer and a second electrode layer on a substrate; A step of providing a lead-out electrode layer on the substrate in a region that does not overlap with the photoelectric conversion layer when the substrate is viewed from above; a step of providing a first encapsulation layer on the second electrode layer and the extraction electrode layer, wherein the first encapsulation layer has a first opening in a region corresponding to the extraction electrode layer; a step of providing a second encapsulation layer on the first encapsulation layer; and a step of removing a portion of the second encapsulation layer to form a second opening, The first encapsulation layer and the second encapsulation layer are arranged to form the second opening in such a manner that the extraction electrode is exposed by means of the first opening and the second opening when the substrate is viewed from the side on which the photoelectric conversion layer is arranged, and the peripheral portion of the extraction electrode layer is covered by at least one of the first encapsulation layer and the second encapsulation layer.

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