Bifacial three-terminal tandem solar cell

Abstract

The present invention relates to a bifacial three-terminal tandem solar cell, more specifically to a bifacial three-terminal tandem solar cell having three electrodes in the tandem solar cell, and provided with transparent electrodes that are on both sides to absorb light from both sides and that are spaced apart at a particular ratio to prevent drop in efficiency due to current mismatching and to improve the efficiency of the solar cell.

Description

Bifacial light-receiving 3-terminal tandem solar cell

[0001] The present invention claims the benefit of the filing date of Korean Patent Application No. 10-2024-0154603 filed with the Korean Intellectual Property Office on November 4, 2024, and the entire contents thereof are incorporated into the present invention.

[0002] The present invention relates to a double-sided light-receiving three-terminal tandem solar cell, specifically comprising three electrodes included in the tandem solar cell, and having transparent electrodes on both sides to absorb light from both sides, while the electrodes are spaced apart at a specific ratio to prevent a decrease in efficiency due to current mismatching and to improve the efficiency of the solar cell.

[0003] With the launch of the new climate regime through the Paris Agreement, the Korean government aims to reduce greenhouse gas emissions by 37% compared to the 2030 Business As Usual (BAU) forecast of 850 million tons. Consequently, solar cell technology is expected to generate economic value based on the Paris Agreement and the national strategy for green growth. The solar power market has continued to experience remarkable growth over the past few years due to factors such as the severity of climate change, increasing concern over environmental pollution, and rising energy demand. Silicon solar cells, which currently account for a large share of the market, possess high photovoltaic conversion efficiency but have drawbacks, including a relatively low light absorption coefficient, expensive wafer costs, complex manufacturing processes, and the need for high-temperature heat treatment. To address these issues, thin-film solar cells are gaining attention for their high light absorption coefficients, which allow them to absorb and utilize light effectively with only a small amount of material. Furthermore, active research is being conducted to achieve high efficiency in tandem solar cells, which combine thin-film solar cells.

[0004] Conventionally, there are two-terminal tandem solar cells in which an upper cell and a lower cell are connected in series, but there are limitations on current mismatching, and there is a problem where the output decreases when the current matching deviates from a specific range.

[0005] There is a two-terminal tandem solar cell that receives light from both sides as an improved solar cell, but it had limitations regarding current mismatching, similar to the tandem solar cell that receives light from one side. Furthermore, the Interdigitated Back Contact (IBC) three-terminal tandem solar cell designed to solve current mismatching is free from the tandem current mismatching problem, but it had the problem of not being able to utilize back reflected light.

[0006] Ultimately, there was a need to develop a solar cell capable of improving power generation efficiency by receiving light from both the front and back sides, that is, both sides, while minimizing efficiency variations caused by current mismatch.

[0007] The technical problem that the present invention aims to solve is to provide a double-sided light-receiving 3-terminal tandem solar cell that improves power conversion efficiency by receiving light from both sides of the solar cell and prevents the reduction of power conversion efficiency due to current mismatch.

[0008] However, the problems that the present invention aims to solve are not limited to those mentioned above, and other unmentioned problems will be clearly understood by those skilled in the art from the description below.

[0009] One embodiment of the present invention includes a first transparent electrode (100); a first solar cell (200); and a recombination layer (300); The first transparent electrode (100) is provided with a first terminal (111) on a side opposite to the side on which the first solar cell (200) is provided, and the second solar cell (400) is provided with an n-type semiconductor layer (500) and a p-type semiconductor layer (600) are each provided spaced apart on a part of the side opposite to the side on which the recombination layer (300) is provided, and the second transparent electrode (510) and the second terminal (511) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, and the third transparent electrode (610) and the third terminal (611) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, and the second solar cell (400) is provided on the side opposite to the side on which the second solar cell (400) is provided, and the second transparent electrode (610) and the third terminal (611) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, in the p-type semiconductor layer (600). A double-sided light-receiving 3-terminal tandem solar cell (1000) is provided.

[0010] According to one embodiment of the present invention, the width (W) of the n-type semiconductor layer (500) n ) is the width (W) of the p-type semiconductor layer (600). p It may be more than 2 times and less than 3 times )

[0011] According to one embodiment of the present invention, it may satisfy the following mathematical formula 1.

[0012] [Mathematical Formula 1]

[0013] ω = W g / W d > 0.6

[0014] The above W g is the minimum separation distance between the second terminal (511) and the third terminal (611), and the W d is W d = W m + W g It is, and the above W m is the width of either the second terminal (511) or the third terminal (611).

[0015] According to one embodiment of the present invention, each of the first transparent electrode (111), the second transparent electrode (511), and the third transparent electrode (611) may comprise a material selected from the group consisting of instrinsic-ZnO (intrinsic zinc oxide, i-ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), aluminum-doped zinc oxide (Al-doped ZnO: AZO), boron-doped zinc oxide (B-doped ZnO: BZO), fluorine-doped tin oxide (F-doped SnO: FTO), and combinations thereof.

[0016] According to one embodiment of the present invention, the first solar cell (200) may sequentially have a hole transport layer (210), a perovskite-based light absorption layer (220), and an electron transport layer (230).

[0017] According to one embodiment of the present invention, the hole transport layer (210) may be a P-type semiconductor material.

[0018] According to one embodiment of the present invention, the electron transport layer (230) may be an n-type semiconductor material.

[0019] According to one embodiment of the present invention, the second solar cell (400) may sequentially comprise one selected from a P-type doped silicon light-absorbing layer or an N-type doped silicon light-absorbing layer; and a lower electrode layer.

[0020] According to one embodiment of the present invention, the n-type semiconductor layer (500) may be a-Si(n) or nc-Si(n).

[0021] According to one embodiment of the present invention, the p-type semiconductor layer (600) may be a-Si(p) or nc-Si(p).

[0022] According to one embodiment of the present invention, the perovskite-based light-absorbing layer (220) may comprise an organic-inorganic composite halide perovskite compound of the following chemical formula 1.

[0023] [Chemical Formula 1]

[0024] ABX3

[0025] The above A is one selected from the group consisting of CH3NH3, HC(NH2)2, Cs, Rb, and combinations thereof, the above B is one selected from the group consisting of Pb, Sn, and combinations thereof, and the above X is one selected from the group consisting of Cl, Br, I, and combinations thereof.

[0026] According to one embodiment of the present invention, in the above formula 1, A may be represented by the following formula 2, B may be represented by the following formula 3, and X3 may be represented by the following formula 4.

[0027] [Chemical Formula 2]

[0028] [CH3NH3] 1-a-b-c [HC(NH2)2] a Cs b Rb c

[0029] [Chemical Formula 3]

[0030] Pb 1-p Sn p

[0031] [Chemical Formula 4]

[0032] Cl 3-l-m B l I m

[0033] The above a is 0≤a≤1, the above b is 0≤b≤1, the above c is 0≤c≤1, the above p is 0≤a≤1, the above l is 0≤l≤3, and the above m is 0≤m≤3.

[0034] According to one embodiment of the present invention, each of the first terminal (111), the second terminal (511), and the third terminal (611) may be one selected from the group consisting of Pt, Au, Ag, Cu, Al, and combinations thereof.

[0035] A double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention can prevent a decrease in power conversion efficiency due to current mismatch.

[0036] A double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention can improve power conversion efficiency by receiving sunlight on both sides. Specifically, by receiving light from the rear side, it can improve high current density and total power production.

[0037] According to one embodiment of the present invention, a double-sided light-receiving 3-terminal tandem solar cell can have its structure simplified by being formed as an integrated structure.

[0038] FIG. 1 is a schematic diagram of a double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention.

[0039] FIG. 2 is a schematic diagram showing an enlarged portion of a double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention.

[0040] FIG. 3 is a schematic diagram of a first solar cell included in a double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention.

[0041] FIG. 4 is a schematic diagram of a second solar cell included in a double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention.

[0042] Figure 5 is a circuit diagram showing a circuit for simulating the power conversion efficiency of an example and a comparative example.

[0043] Figure 6 is a graph showing the power conversion efficiency of the example and comparative example.

[0044] In this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0045] Throughout this specification, when a component is said to be located "on" another component, this includes not only cases where a component is in contact with another component, but also cases where another component exists between the two components.

[0046] In this specification, "A and / or B" means "A and B, or A or B".

[0047] In this specification, “upper” and “lower” are used to distinguish configurations and may not be used to limit locations.

[0048] In the present specification, “sequentially provided” may be stacked in order, and may not exclude other layers being provided between the stacked layers.

[0049] In this specification, “width of a specific configuration” may mean the shortest side when the specific configuration is formed as a polygon.

[0050] The drawings attached to this specification illustrate preferred embodiments of the invention and explain the principles of the invention together with the description of the invention, but the scope of the invention is not limited thereto. Meanwhile, the shapes, sizes, scales, or proportions of elements in the drawings included in this specification may be exaggerated to emphasize clearer explanations.

[0051] The present invention will be described in more detail below.

[0052] One embodiment of the present invention includes a first transparent electrode (100); a first solar cell (200); and a recombination layer (300); The first transparent electrode (100) is provided with a first terminal (111) on a side opposite to the side on which the first solar cell (200) is provided, and the second solar cell (400) is provided with an n-type semiconductor layer (500) and a p-type semiconductor layer (600) are each provided spaced apart on a part of the side opposite to the side on which the recombination layer (300) is provided, and the second transparent electrode (510) and the second terminal (511) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, and the third transparent electrode (610) and the third terminal (611) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, and the second solar cell (400) is provided on the side opposite to the side on which the second solar cell (400) is provided, and the second transparent electrode (610) and the third terminal (611) are provided sequentially on the side opposite to the side on which the second solar cell (400) is provided, in the p-type semiconductor layer (600). A double-sided light-receiving 3-terminal tandem solar cell (1000) is provided.

[0053] A double-sided light-receiving three-terminal tandem solar cell according to one embodiment of the present invention can prevent a decrease in power conversion efficiency due to current mismatch. A double-sided light-receiving three-terminal tandem solar cell according to one embodiment of the present invention can improve power conversion efficiency by receiving sunlight on both sides. Specifically, by receiving light from the rear side, high current density and total power production can be improved. A double-sided light-receiving three-terminal tandem solar cell according to one embodiment of the present invention can simplify the structure by forming it as an integrated structure.

[0054] FIG. 1 is a schematic diagram of a double-sided light-receiving three-terminal tandem solar cell according to one embodiment of the present invention. With reference to FIG. 1, a double-sided light-receiving three-terminal tandem solar cell according to one embodiment of the present invention will be described in detail.

[0055] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell includes a first transparent electrode (100). By including the first transparent electrode (100) as described above, the light-receiving efficiency from the top can be improved.

[0056] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell includes a first solar cell (200). By including the first solar cell (200) as described above, light in the short wavelength range can be effectively absorbed.

[0057] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell includes a recombination layer (300). By including the recombination layer (300) as described above, the bonding strength between the first solar cell and the second solar cell can be improved.

[0058] According to one embodiment of the present invention, the recombination layer may be the lower electrode layer (420) described later. As described above, by using the recombination layer as the lower electrode layer (420) described later, the bonding strength between the first solar cell and the second solar cell can be improved, and the power conversion efficiency of long wavelength light can be improved by improving the light transmittance.

[0059] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell includes a second solar cell (400). By including the second solar cell (400) as described above, short wavelength light can be effectively absorbed and the power conversion efficiency of short wavelength light can be improved.

[0060] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell has a first terminal (111) on the other side of the first transparent electrode (100), which is the opposite side of the first solar cell (200) on which the first solar cell (200) is provided.

[0061] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell has an n-type semiconductor layer (500) and a p-type semiconductor layer (600) each spaced apart on a part of the other side, which is opposite to the side on which the recombination layer (300) is provided in the second solar cell (400). As described above, by having the n-type semiconductor layer (500) and the p-type semiconductor layer (600) spaced apart, light received from the rear can be effectively converted.

[0062] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell has a second transparent electrode (510) and a second terminal (511) sequentially provided on the other side of the n-type semiconductor layer (500), which is the opposite side of the side on which the second solar cell (400) is provided.

[0063] According to one embodiment of the present invention, the double-sided light-receiving 3-terminal tandem solar cell has a third transparent electrode (610) and a third terminal (611) sequentially provided on the other side of the p-type semiconductor layer (600), which is the opposite side of the side on which the second solar cell (400) is provided.

[0064] According to one embodiment of the present invention, the recombination layer may be a layer that physically contacts and electrically connects the first solar cell. As described above, by the recombination layer physically contacting and electrically connecting the first solar cell, the bonding strength between the first solar cell and the second solar cell of the tandem solar cell can be improved.

[0065] FIG. 2 is a schematic diagram showing an enlarged portion of a double-sided light-receiving 3-terminal tandem solar cell according to one embodiment of the present invention. Referring to FIG. 2, the width (W) of the n-type semiconductor layer (500) n ), width (W) of the p-type semiconductor layer (600) p ), minimum separation distance (W) between the second terminal (511) and the third terminal (611) g), the width (W) of either the second terminal (511) or the third terminal (611) d ) and the above W d Explain in detail.

[0066] According to one embodiment of the present invention, the width (W) of the n-type semiconductor layer (500) n ) is the width (W) of the p-type semiconductor layer (600). p It may be more than 2 times and less than 3 times with respect to ). Within the range described above, the width (W) of the n-type semiconductor layer (500) n ) and the width (W) of the p-type semiconductor layer (600) p By adjusting the ratio, power conversion efficiency can be improved.

[0067] According to one embodiment of the present invention, it may satisfy the following mathematical formula 1.

[0068] [Mathematical Formula 1]

[0069] ω = W g / W d > 0.6

[0070] The above W g is the minimum separation distance between the second terminal (511) and the third terminal (611), and the W d is W d = W m + W g It is, and the above W m is the width of either the second terminal (511) or the third terminal (611).

[0071] By adjusting ω within the aforementioned range, power conversion efficiency can be improved.

[0072] According to one embodiment of the present invention, each of the first transparent electrode (111), the second transparent electrode (511), and the third transparent electrode (611) may comprise a material selected from the group consisting of instrinsic-ZnO (intrinsic zinc oxide, i-ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), aluminum-doped zinc oxide (Al-doped ZnO: AZO), boron-doped zinc oxide (B-doped ZnO: BZO), fluorine-doped tin oxide (F-doped SnO: FTO), and combinations thereof. By selecting each of the first transparent electrode (111), the second transparent electrode (511), and the third transparent electrode (611) from the above, transparency can be improved and optical properties can be realized.

[0073] According to one embodiment of the present invention, the first solar cell (200) may sequentially have a hole transport layer (210), a perovskite-based light absorption layer (220), and an electron transport layer (230).

[0074] According to one embodiment of the present invention, the first solar cell (200) may include the perovskite-based light absorption layer (220). As described above, by including the perovskite-based light absorption layer (220), the first solar cell can exhibit device characteristics that absorb short wavelength light, thereby improving the power conversion efficiency of the tandem solar cell.

[0075] According to one embodiment of the present invention, the first solar cell (200) may further include a buffer layer on the hole transport layer (210). By further including the buffer layer as described above, the surface roughness of the first solar cell can be reduced and damage to the hole transport layer can be prevented.

[0076] According to one embodiment of the present invention, the buffer layer may be selected from the group consisting of CdS, ZnSnO, ZnO, ZnSe, SnS2, Cd1-xZnxS (where x is 0≤x≤1) and combinations thereof.

[0077] According to one embodiment of the present invention, the hole transport layer (210) may be a P-type semiconductor material.

[0078] According to one embodiment of the present invention, the hole transport layer (210) is NiOx (0 <x≤3), Me-4PACz([4-(3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid), MeO-2PACz([2-(3,6-Dimethoxy-9H-carbazol-9-yl)ethyl]phosphonic Acid), MEO-4PACZ([4-(3,6-Dimethoxy-9H-carbazol-9-yl)butyl]phosphonic acid), 2PACz([2-(9H-Carbazol-9-yl)ethyl]phosphonic Acid), Br2-EPT, 폴리-[비스(4-페닐)(2,4,6-트리메틸페닐)아민](PTAA), 폴리아닐린, 폴리피롤, 폴리-3,4-에틸렌다이옥시싸이오펜-폴리스타이렌설포네이트(PEDOT:PSS), 스피로-미오타디(Spiro-MeOTAD), 폴리아닐린-캄포설폰산(PANI-CSA) 및 이들의 조합으로 이루어진 군으로부터 선택된 것을 포함할 수 있다. 상술한 것으로부터 상기 정공전달층(210)의 재질을 선택함으로써, 에너지 준위를 조절하고, 광자 효율성을 향상시킬 수 있다.

[0079] According to one embodiment of the present invention, the electron transport layer (230) may be an n-type semiconductor material.

[0080] According to one embodiment of the present invention, the electron transport layer (230) may include a material selected from the group consisting of C60 (fullerene), TiO2, SnO2, ZnO, graphene, PCBM ([6,6]-Phenyl-C61-butyric Acid Methyl Ester) and combinations thereof. By selecting the material of the electron transport layer (230) as described above, the durability of the perovskite-based light absorption layer (220) can be improved.

[0081] According to one embodiment of the present invention, the second solar cell (400) may sequentially comprise one selected from a P-type doped silicon light-absorbing layer or an N-type doped silicon light-absorbing layer (410); and a lower electrode layer (420).

[0082] According to one embodiment of the present invention, the second solar cell (400) may further include a semiconductor layer and a passivation layer between one selected from a P-type doped silicon light-absorbing layer or an N-type doped silicon light-absorbing layer (410); and a lower electrode layer (420).

[0083] According to one embodiment of the present invention, the second solar cell (400) may further include a p-type semiconductor layer and a passivation layer between the p-type doped silicon light-absorbing layer and the lower electrode layer (420) when the second solar cell (400) is a p-type doped silicon light-absorbing layer. The second solar cell (400) may further include an nc-Si (p) as the p-type semiconductor layer and an a-Si (i) passivation layer and an intrinsic amorphous Si passivation layer between the p-type doped silicon light-absorbing layer and the lower electrode layer (420).

[0084] According to one embodiment of the present invention, the second solar cell (400) may further include an n-type semiconductor layer and a passivation layer between the n-type doped silicon light-absorbing layer and the lower electrode layer (420) when the second solar cell (400) is an N-type doped silicon light-absorbing layer. The second solar cell (400) may further include an n-type semiconductor layer of nc-Si (n) and a passivation layer of a-Si (i) and an intrinsic amorphous Si passivation layer between the n-type semiconductor layer and the lower electrode layer (420) when the second solar cell (400) is an N-type doped silicon light-absorbing layer.

[0085] In this specification, a-Si(n) may refer to an n-type semiconductor doped with N atoms in amorphous silicon, and a-Si(p) may refer to a p-type semiconductor doped with P atoms in amorphous silicon. Furthermore, in this specification, nc-Si(n) may refer to an n-type semiconductor doped with N atoms in nanocrystalline silicon, and nc-Si(p) may refer to a p-type semiconductor doped with P atoms in nanocrystalline silicon. Additionally, a-Si(i) may refer to intrinsic type amorphous silicon.

[0086] According to one embodiment of the present invention, the n-type semiconductor layer (500) may be a-Si(n) or nc-Si(n).

[0087] According to one embodiment of the present invention, the n-type semiconductor layer (500) may further include a passivation layer. Specifically, the n-type semiconductor layer (500) may further include an a-Si(i) passivation layer. According to one embodiment of the present invention, the p-type semiconductor layer (600) may be a-Si(p) or nc-Si(p).

[0088] According to one embodiment of the present invention, the p-type semiconductor layer (600) may further include a passivation layer. Specifically, the p-type semiconductor layer (600) may further include an a-Si(i) passivation layer.

[0089] According to one embodiment of the present invention, the passivation layer included on the n-type semiconductor layer (500) and the p-type semiconductor layer (600) may be formed as one by connecting the passivation layer on the n-type semiconductor layer (500) and the passivation layer on the p-type semiconductor layer (600).

[0090] According to one embodiment of the present invention, the perovskite-based light-absorbing layer (220) may comprise an organic-inorganic composite halide perovskite compound of the following chemical formula 1.

[0091] [Chemical Formula 1]

[0092] ABX3

[0093] The above A is one selected from the group consisting of CH3NH3, HC(NH2)2, Cs, Rb, and combinations thereof, the above B is one selected from the group consisting of Pb, Sn, and combinations thereof, and the above X is one selected from the group consisting of Cl, Br, I, and combinations thereof.

[0094] According to one embodiment of the present invention, in the above formula 1, A may be represented by the following formula 2, B may be represented by the following formula 3, and X3 may be represented by the following formula 4.

[0095] [Chemical Formula 2]

[0096] [CH3NH3] 1-a-b-c [HC(NH2)2] a Cs b Rb c

[0097] [Chemical Formula 3]

[0098] Pb1-p Sn p

[0099] [Chemical Formula 4]

[0100] Cl 3-l-m B l I m

[0101] The above a is 0≤a≤1, the above b is 0≤b≤1, the above c is 0≤c≤1, the above p is 0≤a≤1, the above l is 0≤l≤3, and the above m is 0≤m≤3.

[0102] According to one embodiment of the present invention, the perovskite-based light absorption layer (220) is CH3NH3 + , CH3NH3PbI3, CH3NH3PbI y Br 3-y , CH3NH3PbI y Cl 3-y , CH3NH3PbCl y Br 3-y , HC(NH2)2 + , HC(NH2)2PbI3, HC(NH2)2PbI y Br 3-y , HC(NH2)2PbI y Cl 3-y , HC(NH2)2PbCl y Br 3-y , (CH3NH3) z (HC(NH2)2) 1-z PbI y Cl 3-y , (CH3NH3) z (HC(NH2)2) 1-z PbI y Br 3-y , (CH3NH3) z (HC(NH2)2) 1-z It may include PbI3 (where 0≤y≤3, 0≤z≤1) and combinations thereof, selected from the group consisting of combinations thereof. By selecting the material of the organic halide perovskite compound from the above, the power conversion efficiency of the first solar cell can be improved.

[0103] According to one embodiment of the present invention, the inorganic halide perovskite compound is Cs + , CsPbI3, CsPbI y Br 3-y , CsPbI y Cl 3-y , CsPbCl y Br 3-y , Rb + , RbPbI3, RbPbI y Br 3-y , RbPbI y Cl 3-y , RbPbCl y Br 3-y , Cs z Rb 1-z PbI y Cl 3-y , Cs z Rb 1-z PbI y Br 3-y , Cs z Rb 1-z It may include PbI3 (where 0≤y≤3, 0≤z≤1) and combinations thereof, selected from the group consisting of combinations thereof. As described above, by selecting the material of the inorganic halide perovskite compound, power conversion efficiency can be improved.

[0104] According to one embodiment of the present invention, the metal halide perovskite compound may comprise one selected from the group consisting of PbCl2, PbBr, PbI, and combinations thereof. By selecting the material of the metal halide perovskite compound as described above, power conversion efficiency can be improved.

[0105] According to one embodiment of the present invention, the organic-inorganic complex halide perovskite compound is [CH3NH3] 1-a-b-c [HC(NH2)2] a [Cs] b [Rb] c PbI3, [CH3NH3] 1-a-b-c [HC(NH2)2] a[Cs] b [Rb] c PbI y Br 3-y , [CH3NH3] 1-a-bc [HC(NH2)2] a [Cs] b [Rb] c PbI y Cl 3-y , [CH3NH3] 1-a-b-c [HC(NH2)2] a [Cs] b [Rb] c PbCl y Br 3-y , [CH3NH3] 1-a-b-c [HC(NH2)2] a [Cs] b [Rb] c + It may include those selected from the group consisting of (wherein 0≤a≤1, 0≤b≤1, 0≤c≤1, 0≤y≤3) and combinations thereof. As described above, by selecting the material of the organic-inorganic composite halide perovskite compound, power conversion efficiency can be improved.

[0106] According to one embodiment of the present invention, each of the first terminal (111), the second terminal (511), and the third terminal (611) may be the first metal terminal, the second metal terminal, and the third metal terminal.

[0107] According to one embodiment of the present invention, each of the first terminal (111), the second terminal (511), and the third terminal (611) may be one selected from the group consisting of Pt, Au, Ag, Cu, Al, and combinations thereof.

[0108] Hereinafter, the present invention will be described in detail with reference to examples to specifically explain the invention. However, the embodiments according to the present invention may be modified in various different forms, and the scope of the present invention is not to be interpreted as being limited to the embodiments described below. The embodiments of this specification are provided to more completely explain the present invention to those with average knowledge in the art.

[0109] Example 1 (Bi-facial light-receiving 3-terminal tandem solar cell, Bi-facial 3T)

[0110] Copper (Cu) as the first terminal; indium zinc oxide (IZO) as the first transparent electrode; a first solar cell comprising a double layer sequentially stacked with C60 (fullerene) and SnO2 as the electron transport layer, and a perovskite-based light absorption layer with a 1.55 eV bandgap (Cs 0.05 MA 0.05 FA 0.9 Pb I 0.95 Br 0.05 A ) and a hole transport layer ((3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz) sequentially stacked; indium tin oxide (ITO) as a recombination layer (used as a bottom electrode layer); a second solar cell sequentially stacking a passivation layer a-Si(i) (intrinsic amorphous Si passivation layer), an n-type semiconductor layer nc-Si(n) (n-type nanocrystalline silicon), and an N-type doped silicon light absorption layer Si(n); and a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer; are sequentially stacked, and

[0111] In a part of the above passivation layer, a-Si(n) (n-type amorphous silicon layer) as an n-type semiconductor layer; indium zinc oxide (IZO) as a second transparent electrode; and copper (Cu) as a second electrode are sequentially stacked.

[0112] A double-sided light-receiving 3-terminal tandem solar cell was manufactured with a structure in which a-Si(p) (p-type amorphous silicon layer) as a p-type semiconductor layer spaced apart from the n-type semiconductor layer in a part of the passivation layer; indium zinc oxide (IZO) as a third transparent electrode; and copper (Cu) as a third electrode are sequentially stacked.

[0113] Comparative Example 1 (Bi-facial light-receiving 2-terminal tandem solar cell, Bi-facial 2T)

[0114] Copper (Cu) as the first terminal; indium zinc oxide (IZO) as the first transparent electrode; a first solar cell comprising a double layer sequentially stacked with C60 (fullerene) and SnO2 as the electron transport layer, and a perovskite-based light absorption layer with a 1.55 eV bandgap (Cs 0.05 MA 0.05 FA 0.9 Pb I 0.95 Br 0.05 ) and a hole transport layer ((3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz) sequentially stacked; indium tin oxide (ITO) as a recombination layer (used as a bottom electrode layer); as a second solar cell, a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer, nc-Si(n) (n-type nanocrystalline silicon) as an n-type semiconductor layer, and Si(n) as an N-type doped silicon light absorption layer; and a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer; are sequentially stacked, and

[0115] A double-sided light-receiving two-terminal tandem solar cell was manufactured with a structure in which a-Si(p) (p-type amorphous silicon layer) as a p-type semiconductor layer; indium zinc oxide (IZO) as a second transparent electrode; and copper (Cu) as a second electrode are sequentially stacked on the passivation layer.

[0116] Comparative Example 2 (Single-sided light-receiving 2-terminal tandem solar cell, Mono-facial 2T)

[0117] Copper (Cu) as the first terminal; indium zinc oxide (IZO) as the first transparent electrode; a first solar cell comprising a double layer sequentially stacked with C60 (fullerene) and SnO2 as the electron transport layer, and a perovskite-based light absorption layer with a 1.63 eV bandgap (Cs 0.05 (FA 0.83 MA 0.17 ) 0.95 Pb(I 0.83 Br 0.17 )3) and a hole transport layer ((3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz) sequentially stacked; indium tin oxide (ITO) as a recombination layer (used as a bottom electrode layer); as a second solar cell, a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer, nc-Si(n) (n-type nanocrystalline silicon) as an n-type semiconductor layer, and Si(n) as an N-type doped silicon light absorption layer; and a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer; are sequentially stacked, and

[0118] A single-sided light-receiving two-terminal tandem solar cell was manufactured with a structure in which a-Si(p) (p-type amorphous silicon layer) as a p-type semiconductor layer; indium zinc oxide (IZO) as a second transparent electrode; and copper (Cu) as a second electrode were sequentially stacked on the passivation layer, and the second electrode was manufactured to be provided over the entire area of ​​the passivation layer.

[0119] Comparative Example 3 (Single-sided light-receiving 3-terminal tandem solar cell, Mono-facial 3T)

[0120] Copper (Cu) as the first terminal; indium zinc oxide (IZO) as the first transparent electrode; a first solar cell comprising a double layer sequentially stacked with C60 (fullerene) and SnO2 as the electron transport layer, and a perovskite-based light absorption layer with a 1.55 eV bandgap (Cs 0.05 MA 0.05 FA 0.9 Pb I 0.95 Br 0.05 A ) and a hole transport layer ((3,6-dimethyl-9H-carbazol-9-yl)butyl]phosphonic acid (Me-4PACz) sequentially stacked; indium tin oxide (ITO) as a recombination layer (used as a bottom electrode layer); a second solar cell sequentially stacking a passivation layer a-Si(i) (intrinsic amorphous Si passivation layer), an n-type semiconductor layer nc-Si(n) (n-type nanocrystalline silicon), and an N-type doped silicon light absorption layer Si(n); and a-Si(i) (intrinsic amorphous Si passivation layer) as a passivation layer; are sequentially stacked, and

[0121] In a part of the above passivation layer, a-Si(n) (n-type amorphous silicon layer) as an n-type semiconductor layer; indium zinc oxide (IZO) as a second transparent electrode; and copper (Cu) as a second electrode are sequentially stacked.

[0122] A single-sided light-receiving 3-terminal tandem solar cell was manufactured with a structure in which a-Si(p) (p-type amorphous silicon layer) as a p-type semiconductor layer is sequentially stacked in a part of the passivation layer, spaced apart from the n-type semiconductor layer; indium zinc oxide (IZO) as a third transparent electrode; and copper (Cu) as a third electrode are sequentially stacked. Although the second electrode and the third electrode are spaced apart, the area where the passivation layer is exposed is manufactured to be less than 1% of the total area.

[0123] Experimental Example 1

[0124] For the above Example 1 and Comparative Examples 1 to 3, the power conversion efficiency was measured by PSpice simulation for current mismatching by adjusting Albedo to 0.1, 0.2, and 0.3, and for Comparative Examples 2 and 3, the power conversion efficiency was measured by PSpice simulation for current mismatching by adjusting Albedo to 0.0.

[0125] FIG. 5 is a circuit diagram showing a circuit for simulating the power conversion efficiency of an example and a comparative example. The symbols described in FIG. 5 are summarized in Table 1 below.

[0126] Abbreviation DescriptionAbbreviation DescriptionI_PerovCurrent of PerovskiteRs_PerovPerovskite series resistanceI_IBCCurrent of IBCRsh_PerovPerovskite shunt resistanceV_T_RVoltage between T&R terminalsRsh_IBCIBC SHJ shunt resistanceV_R_ZVoltage between R&Z terminalsRs_IBC(p)Shared IBC SHJ series resistance componentsD1Perovskite diodeRs_IBC(n)series resistance of n-contactD2silicon diodeR_ICInterconnection resistance

[0127] Specifically, to measure the power conversion efficiency for current mismatching, PSpice simulation was performed using the circuit shown in Fig. 5 above. The numerical values ​​of each variable for the simulation are indicated in Table 2 below.

[0128] I_Perov(unit: mA)I_IBC(unit: mA)V_T_R(unit: V)V_R_Z(unit: V)D1(J0, unit: A / cm 2 )D2(J0, unit: A / cm 2)Mono-facial 2T, Albedo 0.0(Comparative Example 2)20201.5770.61.6X10 -15 4.5X10 -14 Mono-facial 3T, Albedo 0.0(Comparative Example 3)20201.5770.61.6X10 -15 4.5X10 -14 Bi-facial, 2T, Albedo 0.1 (Comparative Example 1) 212 11.5 77 0.6 1.6 X 10 -15 4.5X10 -14 Bi-facial, 3T, Albedo 0.1 (Example 1) 212 11.5 7 7 0.6 1.6 X 10 -15 4.5X10 -14 Bi-facial, 2T, Albedo 0.2 (Comparative Example 1) 2222 1.5 77 0.6 1.6 X 10 -15 4.5X10 -14 Bi-facial, 3T, Albedo 0.2 (Example 1) 2222 1.5 77 0.6 1.6 X 10 -15 4.5X10 -14 Bi-facial, 2T, Albedo 0.3 (Comparative Example 1) 2323 1.577 0.6 1.6X10 -15 4.5X10 -14 Bi-facial, 3T, Albedo 0.3 (Example 1) 2323 1.577 0.6 1.6X10 -15 4.5X10 -14 Rs_Perov(unit: Ωcm 2 )Rsh_Perov(Unit: Ωcm 2 )Rsh_IBC(Unit: Ωcm 2 )Rs_IBC(p)(Unit: Ωcm 2 )Rs_IBC(n)(Unit: Ωcm 2 )R_IC(Unit: Ωcm 2)Mono-facial 2T, Albedo 0.0 (Comparative Example 2) 3.46000100000.5-0.3 Mono-facial 3T, Albedo 0.0 (Comparative Example 3) 3.46000100000.50.30.3 Bi-facial, 2T, Albedo 0.1 (Comparative Example 1) 3.46000100000.5-0.3 Bi-facial, 3T, Albedo 0.1 (Example 1) 3.46000100000.50.30.3 Bi-facial, 2T, Albedo 0.2 (Comparative Example 1) 3.46000100000.5-0.3 Bi-facial, 3T, Albedo 0.2 (Example 1) 3.46000100000.50.30.3 Bi-facial, 2T, Albedo 0.3 (Comparative Example 1) 3.46000100000.5-0.3 Bi-facial, 3T, Albedo 0.3 (Example 1) 3.46000100000.50.30.3

[0129] Figure 6 is a graph showing the power conversion efficiency of the examples and comparative examples. Specifically, it is a graph showing the power conversion efficiency of Example 1 and Comparative Examples 1 to 3 according to the numerical values ​​of the PSpice simulation variables in Table 2.

[0130] Referring to Figure 6 above, Comparative Example 1 and Comparative Example 2, which are 2-terminal tandem solar cells, both showed a decrease in power conversion efficiency due to current mismatch.

[0131] Furthermore, it was confirmed that Example 1, which is a double-sided light-receiving type, is a 3-terminal tandem solar cell, but compared to Comparative Example 3, which is a single-sided light-receiving type, the power conversion efficiency was improved.

[0132] [Explanation of the symbol]

[0133] 100: First transparent electrode

[0134] 111: First terminal

[0135] 200: The first solar cell

[0136] 210: Hole transport layer

[0137] 220: Perovskite-based light absorption layer

[0138] 230: Electron transport layer

[0139] 300: Recombination layer

[0140] 400: Second solar cell

[0141] 410: One selected from a P-type doped silicon light-absorbing layer or an N-type doped silicon light-absorbing layer

[0142] 420: Lower electrode layer

[0143] 500: n-type semiconductor layer

[0144] 510: Second transparent electrode

[0145] 511: Terminal 2

[0146] 600: p-type semiconductor layer

[0147] 610: Third transparent electrode

[0148] 611: Third terminal

Claims

1. First transparent electrode; First solar cell; Reconnection layer; and It sequentially includes a second solar cell, A first terminal is provided on the other side opposite to the side on which the first solar cell is provided in the first transparent electrode, and In the second solar cell above, an n-type semiconductor layer and a p-type semiconductor layer are each spaced apart and provided on a part of the other surface opposite to the surface on which the recombination layer is provided. A second transparent electrode and a second terminal are sequentially provided on the other side opposite to the side on which the second solar cell is provided in the n-type semiconductor layer, and A double-sided light-receiving 3-terminal tandem solar cell in which a third transparent electrode and a third terminal are sequentially provided on the other side opposite to the side on which the second solar cell is provided in the p-type semiconductor layer.

2. In Claim 1, The width (W) of the above n-type semiconductor layer n ) is the width of the p-type semiconductor layer (W p A double-sided light-receiving 3-terminal tandem solar cell that is 2 times or more and 3 times or less with respect to ).

3. In Claim 1, A bifacial light-receiving 3-terminal tandem solar cell satisfying the following mathematical formula 1: [Mathematical Formula 1] ω = W g / W d > 0.6 The above W g is the minimum separation distance between the second terminal and the third terminal, and The above W d is W d = W m + W g It is, The above W m is the width of either the second terminal or the third terminal.

4. In Claim 1, A double-sided light-receiving 3-terminal tandem solar cell wherein each of the first transparent electrode, the second transparent electrode, and the third transparent electrode comprises a material selected from the group consisting of instrinsic-ZnO (intrinsic zinc oxide, i-ZnO), indium tin oxide (ITO), indium zinc oxide (IZO), zinc tin oxide (ZTO), aluminum-doped zinc oxide (Al-doped ZnO: AZO), boron-doped zinc oxide (B-doped ZnO: BZO), fluorine-doped tin oxide (F-doped SnO: FTO), and combinations thereof.

5. In Claim 1, The above-mentioned first solar cell is a double-sided light-receiving type 3-terminal tandem solar cell having a hole transport layer, a perovskite-based light-absorbing layer, and an electron transport layer sequentially.

6. In Claim 5, A three-terminal tandem solar cell in which the hole transport layer is a P-type semiconductor material.

7. In Claim 5, A three-terminal tandem solar cell in which the electron transport layer is an n-type semiconductor material.

8. In Claim 1, The above-mentioned second solar cell is a double-sided light-receiving 3-terminal tandem solar cell having one selected from a P-type doped silicon light-absorbing layer or an N-type doped silicon light-absorbing layer; and a bottom electrode layer sequentially provided.

9. In Claim 1, A double-sided light-receiving 3-terminal tandem solar cell in which the n-type semiconductor layer is a-Si (n) or nc-Si (n).

10. In Claim 1, A double-sided light-receiving 3-terminal tandem solar cell in which the p-type semiconductor layer is a-Si (p) or nc-Si (p).

11. In Claim 5, A bifacial light-receiving 3-terminal tandem solar cell wherein the perovskite-based light-absorbing layer comprises an organic-inorganic complex halide perovskite-based compound of the following chemical formula 1: [Chemical Formula 1] ABX3 The above A is one selected from the group consisting of CH3NH3, HC(NH2)2, Cs, Rb, and combinations thereof, and The above B is one selected from the group consisting of Pb, Sn, and combinations thereof, and The above X is one selected from the group consisting of Cl, Br, I and combinations thereof.

12. In Claim 11, In the above chemical formula 1, The above A is represented by the following chemical formula 2, and The above B is represented by the following chemical formula 3, and The above X3 is a bifacial light-receiving 3-terminal tandem solar cell represented by the following chemical formula 4: [Chemical Formula 2] [CH3NH3] 1-a-b-c [HC(NH2)2] a Cs b Rb c [Chemical Formula 3] Pb 1-p Sn p [Chemical Formula 4] Cl 3-l-m B l I m The above a is 0≤a≤1, the above b is 0≤b≤1, and the above c is 0≤c≤1, and The above p is 0≤a≤1, and The above l is 0≤l≤3 and the above m is 0≤m≤3.

13. In Claim 1, A double-sided light-receiving 3-terminal tandem solar cell in which each of the first terminal, second terminal, and third terminal is selected from the group consisting of PT, Au, Ag, Cu, Al, and combinations thereof.

Images