Large-area perovskite thin film, cell and preparation method

Abstract

The invention relates to a large-area perovskite thin film, a cell and a preparation method. The preparation method comprises the following steps: providing a substrate; preparing an inorganic salt layer on the substrate through a vacuum evaporation method; carrying out first annealing treatment on the inorganic salt layer; depositing an organic salt solution on the inorganic salt layer after the first annealing treatment through a solution coating method, and enabling the organic salt solution to react with the inorganic salt layer; and sequentially carrying out vacuum flash evaporation treatment and secondary annealing treatment on the reacted thin film to form the perovskite light absorption layer. The method is used for preparing the large-area perovskite thin film, the cell and the laminated cell, the framework is formed by evaporating the inorganic salt, and then the compact perovskite thin film is formed after the organic salt is coated and annealed.

Description

Technical Field

[0001] This invention relates to the field of perovskite battery technology, and in particular to a large-area perovskite thin film, a battery, and a preparation method thereof. Background Technology

[0002] Solar energy, with its wide distribution and clean, pollution-free nature, holds a dominant position in the future development of new energy sources and has enormous potential. Perovskite solar cells, with their advantages of low cost, high efficiency, and adjustable bandgap, are considered one of the most promising photovoltaic technologies. Currently, the efficiency limit of single-junction perovskite solar cells is 33%, while the efficiency limit of perovskite tandem solar cells exceeds 40%, making it a promising photovoltaic technology for breaking through the efficiency limit of single-junction cells. The highest efficiency achieved so far for perovskite-silicon tandem solar cells is 34.6%, making tandem technology highly competitive in the market.

[0003] Typically, the absorption bandgap of perovskite thin films can be adjusted through composition engineering. For tandem solar cells, a wide bandgap perovskite film acts as the top cell, absorbing higher-energy photons, while the bottom cell can be a tandem solar cell constructed using crystalline silicon or copper indium gallium selenide (CIGS) cells in series. Mainstream tandem solar cells usually choose heterocrystalline silicon cells as the bottom cell, connected in series with perovskite cells. Fabricating high-quality perovskite films on large textured silicon wafers remains a significant challenge. Therefore, large-area vapor deposition combined with slot coating is one of the key technologies for conformal deposition of perovskite films on large textured surfaces, and also an effective way to fabricate large-area perovskite-crystalline silicon tandem solar cells, with broad market potential and prospects for future commercial applications.

[0004] A brief description of the shortcomings of existing technologies: The core problem of incomplete reaction in the two-step process: In the traditional two-step process of "depositing inorganic salts and coating organic salts", the lead halide (such as PbI2) film formed by vacuum evaporation is dense and highly crystalline, making it difficult for the subsequent organic salt solution to fully penetrate and react. This easily leads to unreacted lead halide residues at the interface or inside the film. These residues can become charge recombination centers, seriously damaging device performance.

[0005] Poor adaptability to large-size, textured substrates: Existing processes are applicable to flat substrates, but when faced with crystalline silicon bottom cells with micron-level "pyramid" textures required for industrialization, it is difficult to achieve conformal and seamless coverage. The solution tends to accumulate at the valleys or be insufficiently covered at the tops, resulting in uneven film, leakage, or failure of sub-cells in series.

[0006] The optimization methods are limited and lack synergy: Existing technologies often use a single chemical additive (such as a specific solvent) to try to improve the morphology of inorganic salt layers. This method has limited controllability and may be incompatible with the processes or materials of subsequent functional layers (such as transport layers), lacking a systematic design for synergistic optimization of the entire film growth kinetics and interface energy levels.

[0007] In view of the above-mentioned shortcomings, the designer has actively researched and innovated in order to create a large-area perovskite thin film, battery and preparation method, so as to make it more industrially valuable. Summary of the Invention

[0008] To address the aforementioned technical problems, the present invention aims to provide a large-area perovskite thin film, a battery, and a method for its preparation.

[0009] To achieve the above objectives, the present invention adopts the following technical solution: One of the objectives of this invention is: A method for preparing a large-area perovskite thin film includes the following steps: Step 1: Provide a substrate; Step 2: Prepare an inorganic salt layer on the substrate by vacuum evaporation; Step 3: Perform the first annealing treatment on the inorganic salt layer. The annealing temperature is 100~180℃ and the annealing time is 8~12 minutes. Step 4: Deposit an organic salt solution onto the inorganic salt layer after the first annealing treatment using a solution coating method, so that it reacts with the inorganic salt layer; Step 5: The reacted film is subjected to vacuum flash evaporation and a second annealing treatment in sequence. The annealing temperature is 80~120℃ and the annealing time is 18~22 minutes to form a perovskite light-absorbing layer.

[0010] As a further improvement of the present invention, the inorganic salt layer comprises any one or a combination of two or more of lead halide, alkali metal halide and inorganic metal lead halide, and the thickness of the inorganic salt layer is 250 nm to 400 nm.

[0011] As a further improvement of the present invention, the organic salt solution comprises any one or a combination of two or more of ammonium halide salts, organic ammonium salts and pseudohalogenated ammonium salts, and the concentration of the organic salt solution is 0.5~1.5M.

[0012] The second objective of this invention is: A large-area perovskite thin film is prepared by any of the above-mentioned methods.

[0013] The third objective of this invention: A method for preparing a large-area calcium-titanium battery includes the following steps: Step 1: Provide a substrate and perform a cleaning pretreatment on the substrate surface; Step 2: Prepare the first hole transport layer on the substrate using physical vapor deposition; Step 3: A self-assembled monolayer solution is coated onto the first hole transport layer using a solution method, and after drying, a composite hole transport layer is formed. Step 4: Prepare an inorganic salt layer on the composite hole transport layer by vacuum evaporation. Step 5: Perform the first annealing treatment on the inorganic salt layer; Step 6: Prepare the organic salt solution; Step 7: Coat the organic salt solution onto the inorganic salt layer after the first annealing treatment to form a perovskite wet film; Step 8: The perovskite wet film is subjected to vacuum flash drying and a second annealing treatment in sequence to form a perovskite light-absorbing layer; Step 9: Apply a passivation layer solution onto the perovskite light-absorbing layer using a solution method, and then perform annealing treatment to form a passivation layer; Step 10: Prepare an electron transport layer on the passivation layer by vacuum evaporation. Step 11: Prepare a hole blocking layer on the electron transport layer; Step 12: Prepare the transparent conductive electrode and the metal back electrode in sequence to complete the battery fabrication.

[0014] As a further improvement of the present invention, in step S1, a heterogeneous crystalline silicon cell or a TOPCon crystalline silicon cell is used as the base cell. Before step 2, a step is also included in which a transparent conductive composite layer is prepared on the bottom battery by magnetron sputtering, wherein the sputtering power is 0.8~1.2KW and the thickness is 18~22nm; In step 2, the first hole transport layer is a nickel oxide layer, which is prepared by magnetron sputtering with a sputtering power of 0.8~1.2KW, a thickness of 10~15nm, and a process temperature of 180~220℃. In step 3, the self-assembled monolayer material is selected from MeO-2PACz, Me-4PACz, or 4PADCB, and is applied by a blade coating method and annealed at 80~120℃ for 8~12 minutes.

[0015] As a further improvement of the present invention, in step S4, an inorganic salt layer is prepared by co-evaporation, wherein the evaporation thickness of lead iodide is 280~320nm, and the evaporation rate ratio of lead iodide, cesium halide and lead chloride is 10:1:1. In step S5, the first annealing temperature is 100~180℃, and the annealing time is 8~12 minutes; In step S6, the solvent for the organic salt solution is ethanol; the organic salt includes formamidine iodide, formamidine bromide, and methylamine iodide or methylamine chloride; In step S8, the conditions for vacuum flash drying are: reducing the pressure to 8-12 Pa within 8-12 seconds and maintaining it for 8-12 seconds; the temperature for the second annealing treatment is 80-120℃, and the annealing time is 18-22 minutes.

[0016] As a further improvement of the present invention, in step S9, the passivation layer solution is a piperazine monoiodide isopropanol solution, and the annealing temperature is 80~120℃, and the time is 4~6 minutes. In step S10, the electron transport layer is C. 60 At a vacuum degree of 6×10 -4 Under Pa conditions, vapor deposition was carried out at a rate of 0.1~0.2 Å / s to a thickness of 18~22 nm.

[0017] As a further improvement of the present invention, in step S11, the hole blocking layer is SnO2, which is prepared by atomic layer deposition, the cavity temperature is 70~90℃, TDMASn is used as the tin source, pure water is used as the oxygen source, the outlet temperature is 60~70℃, and the number of cycles is 70~90 times. In step S12, the transparent conductive electrode is an indium tin oxide layer, which is prepared by magnetron sputtering with a sputtering power of 0.8~1.2KW and a thickness of 18~22nm; the metal back electrode is made of copper or silver; when it is a copper electrode, it is prepared by magnetron sputtering; when it is a silver electrode, it is prepared by screen printing silver paste and then curing.

[0018] The fourth objective of this invention: A large-area calcium-titanium battery is prepared by any of the above-mentioned methods.

[0019] By means of the above-described solution, the present invention has at least the following advantages: This invention relates to the fabrication of large-area perovskite thin films and batteries, including tandem batteries. It involves forming a framework by vapor deposition of inorganic salts, followed by coating with organic salts and annealing to form a dense perovskite thin film. This method is compatible with textured surfaces ranging from 0.5 to 3 μm in size, and solves the problem that pyramidal textured surfaces exceeding 2 μm cannot be completely covered by a single coating step. Furthermore, it enables the fabrication of large-area perovskite thin films at 166 nm. 166mm 2 182 183mm 2 210 105mm 2 210 210mm 2 Perovskite thin films were prepared on crystalline silicon of different sizes.

[0020] Compared to directly coating organic salts, the intermediate annealing process of the present invention results in a more complete reaction. Annealing makes the densely deposited inorganic salts more porous, allowing the organic salt solution to penetrate better.

[0021] The above description is merely an overview of the technical solution of the present invention. In order to better understand the technical means of the present invention and to implement it in accordance with the contents of the specification, the following are preferred embodiments of the present invention described in detail with reference to the accompanying drawings. Attached Figure Description

[0022] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0023] Figure 1 This is a schematic diagram of the perovskite / crystalline silicon tandem solar cell in the second or third experimental example of the present invention. Figure 2 The cross-sectional morphology of the battery film in the second or third experimental example of the present invention. Figure 1 ; Figure 3 The cross-sectional morphology of the battery film in the second or third experimental example of the present invention. Figure 2 ; Figure 4 These are XRD comparison images of the films before and after inorganic salt annealing in the second or third experimental example of the present invention. Figure 5 This is an XRD pattern of the battery film of the second or third experimental example of the present invention. Detailed Implementation

[0024] The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and examples. The following examples are for illustrative purposes only and are not intended to limit the scope of the invention.

[0025] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0026] First embodiment of the present invention: This embodiment provides a structure for a large-area perovskite solar cell, wherein the structure includes a hole transport layer, a perovskite light-absorbing layer, a passivation layer, and an electron transport layer. This structure is used as the top cell of a single-junction perovskite solar cell or a tandem solar cell.

[0027] The single-junction perovskite solar cell also includes a conductive substrate and a metal electrode. The perovskite tandem solar cell also includes a bottom cell, a transparent conductive composite layer, and an antireflection layer. The composite layer is used to connect the bottom cell and the top cell in series, and the antireflection layer is used to reduce the reflected light on the thin film surface.

[0028] The method for preparing the perovskite thin film includes a first step of vapor deposition of inorganic salt, a second step of annealing the vapor-deposited film, and a third step of coating with organic salt. The intermediate annealing treatment is included to make the vapor-deposited inorganic salt film more porous, allowing it to fully react with the inorganic salt during organic salt coating.

[0029] Furthermore, the vapor-deposited inorganic salt comprises any one or more substances selected from lead halides, alkali metal halides, and inorganic metal lead halides.

[0030] Furthermore, the coated organic salt comprises any one or more substances selected from ammonium halide salts, organic ammonium salts, and pseudohalogenated ammonium salts.

[0031] Preferably, the lead halide in the vapor-deposited inorganic salt includes any one or more of lead iodide, lead bromide, and lead chloride.

[0032] The alkali metal halide salts include any one or more of the following materials: cesium chloride, rubidium chloride, potassium chloride, lithium chloride, cesium bromide, cesium iodide, rubidium iodide, potassium iodide, and potassium bromide.

[0033] The inorganic metal lead halide includes any one or more of the following materials: cesium lead iodine, cesium lead chloride, cesium lead bromine, and cesium lead iodine bromine.

[0034] Furthermore, the thickness of the evaporated inorganic salt is 250nm~400nm.

[0035] The second step involves annealing the vapor-deposited film at a temperature of 100℃~180℃.

[0036] Preferably, the coated ammonium halide salt includes any one or more of the following materials: formamidinium iodine, methylammonium iodine, formamidinium bromide, formamidinium chloride, methylammonium chloride, methylammonium bromide, methyldiamine iodine, ethylenediamine iodine, and propylenediamine iodine.

[0037] The coated organic ammonium salt includes any one or more of the following materials: urea, thiourea, acrylamide, and benzenesulfonamide.

[0038] The coated pseudohalogen ammonium salt includes any one or more of the following materials: ammonium thiocyanate, methylamine thiocyanate, formamidine thiocyanate, ethylamine thiocyanate, and guanidine thiocyanate.

[0039] Furthermore, the concentration of the coated organic salt is 0.5~1.5M.

[0040] Furthermore, the hole transport layer material is any one or more of poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA), nickel oxide (NiOx), Spiro-TTB, PEDOT-PSS, or self-contained monolayers (SAMs).

[0041] The hole transport layer can be prepared by any of the following methods: spin coating, blade coating, slot coating, inkjet printing, magnetron sputtering, or vacuum evaporation.

[0042] The passivation layer material is any one or more of the following: phenylethyl ammonium iodide, piperazine monoiodide, piperazine iodide, oleylamine iodide, phenylethyl ammonium bromide, oleylamine chloride, ethylenediamine iodide, propylenediamine iodide, and lithium fluoride.

[0043] The passivation layer can be prepared by any of the following methods: spin coating, blade coating, slot coating, inkjet printing, or vacuum evaporation.

[0044] The electron transport layer material is C. 60 Any one or more of the following materials: PCBM, zinc oxide, tin oxide, and titanium oxide.

[0045] The electron transport layer can be prepared by any of the following methods: spin coating, blade coating, slot coating, inkjet printing, vacuum evaporation, or atomic layer deposition.

[0046] Furthermore, the transparent conductive substrate of the single-junction cell can be conductive glass such as indium tin oxide (ITO) or fluorine-doped tin oxide (FTO), or a flexible conductive substrate such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN) coated with ITO or FTO; the metal electrode can be any one of Au, Ag, Al, Cu, or carbon electrode.

[0047] The bottom cell of the tandem battery can be any one of heterocrystalline silicon battery, TOPCON battery, copper indium gallium selenide battery, cadmium telluride battery, narrow bandgap perovskite solar cell, or organic solar cell.

[0048] The transparent conductive composite layer of the series bottom cell and top cell can be any one or more of ITO, IZO, AZO, and FTO; and its preparation method can be any one of magnetron sputtering, metal ion beam deposition, or pulsed laser deposition.

[0049] The antireflection layer material can be any one or more of lithium fluoride, magnesium fluoride, silicon dioxide, polytetrafluoroethylene, and aluminum oxide; and its preparation method can be any one of vacuum evaporation, magnetron sputtering, atomic layer deposition, and chemical vapor deposition.

[0050] The existing two-step method (depositing PbI2 first, then reacting with organic salts) is known, but introducing an annealing step at a specific temperature (100-180℃) between the two steps, targeting the inorganic salt layer, is not common knowledge or a conventional choice. This step directly addresses the persistent problem of PbI2 residue in large-area preparations. Its innovation lies in: ① Physical morphology transformation: making the dense vapor-deposited film loose and porous, creating permeation channels for the organic salt solution; ② Guided chemical phase transition: potentially promoting the formation of intermediate phases such as CsPb2X5, pre-constructing a favorable crystal template. This provides a more fundamental and controllable solution than simply adding chemical additives to the solution or optimizing coating parameters.

[0051] In the fabrication of tandem solar cells on large-textured silicon wafers, a novel hybrid process design is employed: vacuum evaporation (dry method) is used to deposit the inorganic salt "skeleton," combined with solution methods (slot coating / scraping) to complete the organic salt infiltration reaction. Vacuum evaporation ensures the formation of a uniform, conformal inorganic salt layer on the irregular textured surface, solving the problem of poor coverage in pure solution methods; while subsequent solution coating leverages its low cost and ease of large-area processing to complete the conversion. This combination cleverly balances film quality, morphology compatibility, and manufacturing cost, directly addressing the core challenge of "conformal deposition of textured surfaces" in the industrialization of perovskite / crystalline silicon tandem solar cells.

[0052] A composite HTL is formed by combining a NiOx hole transport layer with a self-assembled monolayer (SAM, such as MeO-2PACz); specific molecules (such as PiPl) are introduced behind the perovskite layer for passivation; and SnO2 is deposited as a hole-blocking layer using ALD technology. This entire interface treatment scheme is carefully designed and sequenced. The system achieves step-by-step optimization of interface functions: the composite HTL optimizes energy level alignment and hole extraction; bulk and surface passivation reduces non-radiative recombination; and the dense ALD-SnO2 effectively blocks holes and inhibits ion migration. Each step is interconnected, jointly ensuring efficient and stable charge extraction from large-area thin films.

[0053] The order of steps in this method is strict and cannot be changed arbitrarily; this is the logical basis for achieving its technical effect.

[0054] Intermediate annealing must be performed immediately after the inorganic salt is deposited. If the annealing is performed after the organic salt is coated, the purpose of loosening the skeleton and promoting penetration is lost.

[0055] Vacuum flash evaporation followed by secondary annealing is necessary after coating with organic salt to ensure rapid and uniform removal of solvent and completion of final crystallization. If flash evaporation is omitted and annealing is performed directly, it can easily lead to uneven film.

[0056] The passivation layer must be applied after the perovskite layer is formed and before the electron transport layer is deposited in order to effectively modify the perovskite surface defects.

[0057] The second embodiment of the present invention: This embodiment provides a method for fabricating a large-area perovskite single-junction solar cell, the steps of which include the above-described structure for perovskite solar cells. The steps are as follows: The hole transport layer described above was prepared on a TCO substrate by spin coating, blade coating, slot coating, inkjet printing, magnetron sputtering, and vacuum evaporation. A perovskite light-absorbing layer was prepared on the hole transport layer by vapor deposition of the above-mentioned inorganic salt, annealing the vapor-deposited inorganic salt, and finally coating with organic salt. The above passivation layer was prepared on the perovskite light-absorbing layer by spin coating, blade coating, slot coating, inkjet printing, and vacuum evaporation. The electron transport layer described above was prepared on the passivation layer by means of spin coating, blade coating, slot coating, inkjet printing, vacuum evaporation, and atomic layer deposition. A metal electrode layer is prepared on the electron transport layer by vacuum evaporation or magnetron sputtering to obtain the large-area perovskite single-junction cell.

[0058] In addition, this embodiment also provides a method for fabricating a large-area perovskite tandem solar cell, the steps of which include the above-described structure for perovskite solar cells.

[0059] The specific steps are as follows: A transparent conductive composite layer is prepared on the bottom battery by magnetron sputtering or deposition. The hole transport layer described above was prepared on a transparent composite layer by means of spin coating, blade coating, slot coating, inkjet printing, magnetron sputtering, and vacuum evaporation. A perovskite light-absorbing layer was prepared on the hole transport layer by vapor deposition of the above-mentioned inorganic salt, annealing the vapor-deposited inorganic salt, and finally coating with organic salt. The above passivation layer was prepared on the perovskite light-absorbing layer by spin coating, blade coating, slot coating, inkjet printing, and vacuum evaporation. The electron transport layer described above was prepared on the passivation layer by means of spin coating, blade coating, slot coating, inkjet printing, vacuum evaporation, and atomic layer deposition. A transparent electrode layer is prepared on the electron transport layer by magnetron sputtering or deposition. Metal electrode layers are prepared on transparent electrode layers by vacuum evaporation or magnetron sputtering. An antireflection layer was prepared on the metal electrode layer by vacuum evaporation, magnetron sputtering, atomic layer deposition, and chemical vapor deposition. This yielded the large-area perovskite tandem solar cell.

[0060] First experimental example of the present invention: This experimental example describes a fabrication process for a large-area inverted wide-bandgap perovskite solar cell. ITO is used as the conductive substrate, NiOx and self-assembled monolayer (SAM) are used as the hole transport layer, PbI2 and CsBr are deposited as the inorganic salt framework, a mixed solution of formamidine iodide (FAI), formamidine bromide (FABr), methylamine iodide (MAI), and methylamine chloride (MACl) is coated to form the perovskite light-absorbing layer, and piperazine monoiodide (PiPl) is used as the passivation layer. 60 The electron transport layer is composed of SnO2 as the hole blocking layer, and ITO and Cu are used as the back electrode. The specific steps are as follows: Step 1: Place the laser-etched P1 ITO glass into a cleaning machine for cleaning. After cleaning, perform ultraviolet ozone surface treatment for 15 minutes and then remove it for later use.

[0061] Step 2: The prepared ITO glass is used to prepare a hole transport layer NiOx by vacuum sputtering coating equipment (PVD). The sputtering power is 1KW, the thickness of NiOx is 13nm, and the process temperature is 300℃ to obtain the NiOx hole transport layer.

[0062] Step 3: Coat the surface of the NiOx hole transport layer prepared in Step 2 with a self-assembled monolayer of MeO-2PACz dissolved in ethanol as the hole transport layer. The scraper is 300 μm above the substrate and the scraping speed is 5 mm / s. Take 32 μL of MeO-2PACz ethanol solution and then anneal it on a hot plate at 100 ℃ for 10 min to obtain the MeO-2PACz hole transport layer.

[0063] Step 4: Weigh a certain amount of PbI2 and CsBr and add them to different evaporation crucibles. Use a beam source evaporation device to co-evaporate PbI2 and CsBr. The evaporation rate ratio of PbI2 to CsBr is 10:1. Stop evaporating PbI2 when the thickness is 300 nm. Prepare an inorganic salt film co-evaporated with PbI2 and CsBr.

[0064] Step 5: Place the co-distilled inorganic salt film on a heating platform and anneal at 150°C for 10 minutes to obtain a relatively loose inorganic salt film.

[0065] Step 6: Weigh 700 mg of formamidine iodide (FAI), 500 mg of formamidine bromide, 200 mg of methylamine iodide, and 160 mg of methylamine chloride, respectively, and dissolve them in 20 mL of ethanol to prepare an organic salt solution.

[0066] Step 7: The organic salt solution prepared in Step 6 is injected into the coating equipment through the injection system. The coating blade height is 150 μm and the coating speed is 10 mm / s. After coating, a perovskite wet film is obtained.

[0067] Step 8: Place the perovskite wet film obtained in Step 7 in a vacuum flash furnace. The vacuum flash evaporation is configured to be reduced to 10 Pa in 10 seconds, and the total flash evaporation time is set to 10 seconds. After the flash evaporation is completed, a dry perovskite film is obtained. Then, it is placed on a hot stage heated to 100°C for annealing for 20 minutes. After annealing, it is removed and allowed to cool naturally to obtain a wide-bandgap perovskite film.

[0068] Step 9: Weigh 5 mg of Pipl drug, add 10 mL of isopropanol solvent in a glove box to prepare a 0.5 mg / mL passivation layer solution, shake to fully dissolve it, and then coat the Pipl passivation layer on the wide bandgap film prepared in step 7 at a coating speed of 20 mm / s. After coating, place it on a hot plate heated to 100°C for annealing for 5 min to obtain a perovskite passivation layer.

[0069] Step 10: Apply an electron transport layer C to the passivation layer surface obtained in Step 9 using a vacuum evaporation method. 60 For preparation, the sample is placed on a matching mask and subjected to a vacuum of 6... 10 -4Under the condition of Pa, approximately 20 nm of C is deposited through a linear evaporation source at a rate of 0.15 Å / s. 60 A thin film was used to prepare an electron transport layer.

[0070] Step 11: A hole-blocking layer (SnO2) is prepared on the electron transport layer surface obtained in Step 10 using atomic layer deposition (ALD). The sample is placed in a process vacuum chamber, with the chamber temperature set to a stable 80°C. The tin source is TDMASn, the oxygen source is pure water, the outlet temperature is 65°C, and the number of purging cycles is 80. The hole-blocking layer is thus prepared.

[0071] Step 12: A transparent conductive electrode, ITO, is fabricated on the hole-blocking layer obtained in Step 11 using a vacuum sputtering deposition (PVD) system. After fixing the sample on the substrate holder, it is fed into the deposition chamber via the equipment's transmission system. Once the set vacuum level is reached, the sputtering process is performed. The sputtering power is set to 1 kW, using an argon-oxygen mixture (oxygen content 10%), and the ITO thickness is 20 nm, thus obtaining a transparent ITO electrode. Subsequently, a Cu metal electrode is sputtered at a power of 7 kW, achieving a Cu thickness of 80 nm, thus fabricating a Cu metal electrode. Finally, a large-area inversion wide-bandgap perovskite solar cell is obtained.

[0072] Second experimental example of the present invention: This experimental example describes a fabrication process for a large-area perovskite / heterocrystalline silicon tandem solar cell, using a heterocrystalline silicon cell as the base cell. Figure 1 The structure consists of an ITO intermediate composite layer (numbered 001), a NiOx layer (numbered 002), and a self-assembled monolayer (numbered 003) as a hole transport layer; an inorganic salt framework of PbI2, CsBr, and CsCl deposited by vapor deposition; a perovskite light-absorbing layer (numbered 004) formed by coating with a mixed solution of formamidine iodide (FAI), formamidine bromide (FABr), and methylamine iodide (MAI); a piperazine monoiodide (PiPl) passivation layer (numbered 005); and a C… 60 The structure consists of an electron transport layer, a SnO2 hole-blocking layer (numbered 007), an ITO transparent top electrode (numbered 008), and a silver gate back electrode (numbered 009). The specific steps are as follows: Step 1: An intermediate composite layer ITO is prepared on the n-side of a heterocrystalline silicon substrate using a vacuum sputtering deposition (PVD) system. After fixing the sample on the substrate holder, it is fed into the deposition chamber through the transmission system of the equipment. After reaching the set vacuum level, the sputtering process is performed. The sputtering power is set to 1KW, the gas mixture is argon-oxygen (oxygen content 10%), and the thickness of ITO is 20nm, thus obtaining the intermediate composite layer.

[0073] Step 2: On the surface of the intermediate composite layer ITO prepared in Step 1, a hole transport layer NiOx is prepared by vacuum sputtering deposition equipment (PVD). The sputtering power is 1KW, the thickness of NiOx is 13nm, and the process temperature is 200℃ to obtain the NiOx hole transport layer.

[0074] Step 3: Coat the surface of the NiOx hole transport layer prepared in Step 2 with a self-assembled monolayer of Me-4PACz dissolved in ethanol as the hole transport layer. The scraper is 300 μm above the substrate and the scraping speed is 5 mm / s. Take 32 μL of Me-4PACz ethanol solution and then anneal it on a hot stage at 100 °C for 10 min to obtain the Me-4PACz hole transport layer.

[0075] Step 4: Weigh a certain amount of PbI2, CsBr and CsCl and add them to different evaporation crucibles. Use a beam evaporation device to co-evaporate PbI2, CsBr and CsCl. The evaporation rate ratio of PbI2, CsBr and CsCl is 10:1:1. Stop evaporating PbI2 when the thickness is 300nm. Prepare an inorganic salt film co-evaporated with PbI2, CsBr and CsCl.

[0076] Step 5: Place the co-distilled inorganic salt film on a heating platform and anneal at 150°C for 10 minutes to obtain a relatively loose inorganic salt film.

[0077] Step 6: Weigh 700 mg of formamidine iodide (FAI), 500 mg of formamidine bromide (FABr), and 200 mg of methylamine iodide (MAI), and dissolve them in 20 mL of ethanol to prepare an organic salt solution.

[0078] Step 7: The organic salt solution prepared in Step 6 is injected into the coating equipment through the injection system. The coating blade height is 150 μm and the coating speed is 10 mm / s. After coating, a perovskite wet film is obtained.

[0079] Step 8: Place the perovskite wet film obtained in Step 7 in a vacuum flash furnace. The vacuum flash evaporation is configured to be reduced to 10 Pa in 10 seconds, and the total flash evaporation time is set to 10 seconds. After the flash evaporation is completed, a dry perovskite film is obtained. Then, it is placed on a hot stage heated to 100°C for annealing for 20 minutes. After annealing, it is removed and allowed to cool naturally to obtain a wide-bandgap perovskite film.

[0080] Step 9: Weigh 5 mg of Pipl drug, add 10 mL of isopropanol solvent in a glove box to prepare a 0.5 mg / mL passivation layer solution, shake to fully dissolve it, and then coat the Pipl passivation layer on the wide bandgap film prepared in step 7 at a coating speed of 20 mm / s. After coating, place it on a hot plate heated to 100°C for annealing for 5 min to obtain a perovskite passivation layer.

[0081] Step 10: Apply an electron transport layer C to the passivation layer surface obtained in Step 9 using a vacuum evaporation method. 60 For preparation, the sample is placed on a matching mask and subjected to a vacuum of 6... 10 -4 Under the condition of Pa, approximately 20 nm of C is deposited through a linear evaporation source at a rate of 0.15 Å / s. 60 A thin film was used to prepare an electron transport layer.

[0082] Step 11: A hole-blocking layer (SnO2) is prepared on the electron transport layer surface obtained in Step 10 using atomic layer deposition (ALD). The sample is placed in a process vacuum chamber, with the chamber temperature set to a stable 80°C. The tin source is TDMASn, the oxygen source is pure water, the outlet temperature is 65°C, and the number of purging cycles is 80. The hole-blocking layer is thus prepared.

[0083] Step 12: A transparent conductive electrode, ITO, is fabricated on the hole-blocking layer obtained in Step 11 using a vacuum sputtering deposition (PVD) system. After fixing the sample on the substrate holder, it is fed into the deposition chamber via the equipment's transmission system. Once the set vacuum level is reached, the sputtering process is performed. The sputtering power is set to 1 kW, using an argon-oxygen mixture (oxygen content 10%), and the ITO thickness is 20 nm, thus obtaining the ITO transparent electrode. Subsequently, a silver grid is fabricated by screen printing, with the silver paste curing temperature at 100℃, finally yielding a large-area perovskite / heterocrystalline silicon tandem solar cell.

[0084] The third experimental example of the present invention: This experimental example describes a fabrication process for a large-area perovskite / TOPCon crystalline silicon tandem solar cell. TOPCon crystalline silicon is used as the base cell, ITO as the intermediate composite layer, NiOx and self-contained monolayer (SAM) as the hole transport layer, PbI2, CsBr, and PbCl2 are vapor-deposited as the inorganic salt framework, a mixed solution of formamidine iodide (FAI), formamidine bromide (FABr), and methylamine chloride (MACl) is coated to form the perovskite light-absorbing layer, and piperazine monoiodide (PiPl) is used as the passivation layer. 60 The electron transport layer is formed, SnO2 is used as the hole blocking layer, ITO is used as the transparent top electrode, and a silver gate is used as the back electrode. The specific steps are as follows: Step 1: An intermediate composite layer ITO is prepared on the n-side of the TOPCon crystalline silicon bottom cell using a vacuum sputtering deposition (PVD) system. After fixing the sample on the substrate holder, it is fed into the deposition chamber through the transmission system of the equipment. After reaching the set vacuum level, the sputtering process is performed. The sputtering power is set to 1KW, the gas mixture is argon-oxygen (oxygen content 10%), and the thickness of ITO is 20nm, thus obtaining the intermediate composite layer.

[0085] Step 2: On the surface of the intermediate composite layer ITO prepared in Step 1, a hole transport layer NiOx is prepared by vacuum sputtering deposition equipment (PVD). The sputtering power is 1KW, the thickness of NiOx is 13nm, and the process temperature is 200℃ to obtain the NiOx hole transport layer.

[0086] Step 3: Coat the surface of the NiOx hole transport layer prepared in Step 2 with a self-assembled monolayer of 4PADCB dissolved in ethanol as the hole transport layer. The scraper is 300 μm above the substrate and the scraping speed is 5 mm / s. Take 32 μL of 4PADCB ethanol solution and then anneal it on a hot stage at 100 ℃ for 10 min to obtain the 4PADCB hole transport layer.

[0087] Step 4: Weigh a certain amount of PbI2, CsBr and PbCl2 and add them to different evaporation crucibles. Use a beam evaporation device to co-evaporate PbI2, CsBr and PbCl2. The evaporation rate ratio of PbI2, CsBr and PbCl2 is 10:1:1. Stop evaporating PbI2 when the thickness is 300nm. Prepare an inorganic salt film co-evaporated with PbI2, CsBr and PbCl2.

[0088] Step 5: Place the co-distilled inorganic salt film on a heating platform and anneal at 150°C for 10 minutes to obtain a relatively loose inorganic salt film.

[0089] Step 6: Weigh 4 mmol of formamidine iodide (FAI), 4 mmol of formamidine bromide (FABr), and 1 mmol of methylamine chloride (MACl), and dissolve them in 20 mL of ethanol to prepare an organic salt solution.

[0090] Step 7: The organic salt solution prepared in Step 6 is injected into the coating equipment through the injection system. The coating blade height is 150 μm and the coating speed is 10 mm / s. After coating, a perovskite wet film is obtained.

[0091] Step 8: Place the perovskite wet film obtained in Step 7 in a vacuum flash furnace. The vacuum flash evaporation is configured to be reduced to 10 Pa in 10 seconds, and the total flash evaporation time is set to 10 seconds. After the flash evaporation is completed, a dry perovskite film is obtained. Then, it is placed on a hot stage heated to 100°C for annealing for 20 minutes. After annealing, it is removed and allowed to cool naturally to obtain a wide-bandgap perovskite film.

[0092] Step 9: Weigh 5 mg of Pipl drug, add 10 mL of isopropanol solvent in a glove box to prepare a 0.5 mg / mL passivation layer solution, shake to fully dissolve it, and then coat the Pipl passivation layer on the wide bandgap film prepared in step 7 at a coating speed of 20 mm / s. After coating, place it on a hot plate heated to 100°C for annealing for 5 min to obtain a perovskite passivation layer.

[0093] Step 10: Apply an electron transport layer C to the passivation layer surface obtained in Step 9 using a vacuum evaporation method. 60 For preparation, the sample is placed on a matching mask and subjected to a vacuum of 6... 10 -4 Under the condition of Pa, approximately 20 nm of C is deposited through a linear evaporation source at a rate of 0.15 Å / s. 60 A thin film was used to prepare an electron transport layer.

[0094] Step 11: A hole-blocking layer (SnO2) is prepared on the electron transport layer surface obtained in Step 10 using atomic layer deposition (ALD). The sample is placed in a process vacuum chamber, with the chamber temperature set to a stable 80°C. The tin source is TDMASn, the oxygen source is pure water, the outlet temperature is 65°C, and the number of purging cycles is 80. The hole-blocking layer is thus prepared.

[0095] Step 12: A transparent conductive electrode, ITO, is fabricated on the hole-blocking layer obtained in Step 11 using a vacuum sputtering deposition (PVD) system. After fixing the sample on the substrate holder, it is fed into the deposition chamber via the equipment's transmission system. Once the set vacuum level is reached, the sputtering process is performed. The sputtering power is set to 1 kW, using an argon-oxygen mixture (oxygen content 10%), and the ITO thickness is 20 nm, thus obtaining the ITO transparent electrode. Subsequently, a silver grid is fabricated by screen printing. The silver paste is cured at 150°C, finally yielding a large-area perovskite / TOPCon crystalline silicon tandem solar cell.

[0096] In the above experimental example, an intermediate annealing at 150°C was introduced after vapor deposition and before coating. This step made the dense inorganic salt film loose and porous, greatly promoting the penetration and reaction kinetics of the subsequent organic salt solution. This ensured a complete and sufficient reaction between the inorganic and organic salts, thoroughly eliminating inactive lead halide residues and reducing charge recombination losses.

[0097] Intermediate annealing promotes the formation of intermediate phases such as CsPb2X5 from inorganic salt mixtures (e.g., PbI2-CsBr), providing an ideal framework for the subsequent formation of perovskite films with good crystallinity and few defects. It also induces the formation of high-quality perovskite crystallization precursor phases, creating crystal templates that are more conducive to the growth of high-quality perovskites.

[0098] Vacuum evaporation itself has excellent step coverage; the loose framework formed by intermediate annealing, combined with the dynamic solution process of slot coating / scraping, ensures uniform spreading and reaction of the solution on complex three-dimensional morphologies. It is perfectly adapted to large textured silicon wafers to achieve conformal deposition: it can achieve full coverage on "pyramid" textured surfaces exceeding 2μm, with no exposed pyramid tips, thus avoiding leakage.

[0099] The first to third experimental examples described above demonstrate successful fabrication on ITO glass, HJT, and TOPCon substrates, respectively, verifying the universality and scalability of the process. Applicable to large-area, multi-layered battery structures: the process is stable and scalable to 210×210 mm. 2 Sizes of 10 and above are compatible with various high-efficiency crystalline silicon bottom cells such as HJT and TOPCon.

[0100] Intermediate annealing ensures a high-quality light-absorbing layer; the NiOx / SAM composite hole transport layer optimizes interface energy levels and hole extraction; the PiPl passivation layer + C 60 The SnO2 electron transport layer suppresses interfacial recombination. The effects of each step are cumulative, significantly improving the photoelectric conversion efficiency of the final device: the high efficiency is due to the high-quality, fully covered light-absorbing layer and the optimized interface.

[0101] Unlike existing technologies that employ "chemical modification," this invention innovatively alters the fundamental material state of the two-step reaction through a simple physical heat treatment step, thus solving the root cause of incomplete reaction.

[0102] This invention provides a complete and industrially viable technical solution package, from the underlying thin film growth mechanism (intermediate annealing), to the intermediate interface engineering (composite transport layer, passivation layer), and then to the top-level optical and electrical management (transparent electrode, antireflection layer). Each step is interconnected and works together towards the industrialization goal of "high efficiency, large area, and high yield".

[0103] The effects of the preparation method of the present invention will be illustrated below using experimental data as an example.

[0104] Figure 1 The diagram shows a structural model of a perovskite / heterocrystalline silicon solar cell. A structure for a perovskite / crystalline silicon tandem solar cell is also provided, consisting of... Figure 1 It can be seen that, Figure 1The structure consists of an ITO intermediate composite layer (numbered 001), a NiOx layer (numbered 002), and a self-assembled monolayer (numbered 003) as a hole transport layer; an inorganic salt framework of PbI2, CsBr, and CsCl deposited by vapor deposition; a perovskite light-absorbing layer (numbered 004) formed by coating with a mixed solution of formamidine iodide (FAI), formamidine bromide (FABr), and methylamine iodide (MAI); a piperazine monoiodide (PiPl) passivation layer (numbered 005); and a C… 60 The perovskite consists of an electron transport layer, a hole-blocking layer (SnO2, number 007), a transparent ITO top electrode (008), and a silver grid back electrode (009). The annealing step of the inorganic salts effectively loosens the inorganic salt framework during the preparation of the perovskite light-absorbing layer, allowing the organic salt solution to permeate and complete molecular exchange to form an ABX3 crystal structure perovskite film. This tandem cell structure, combining perovskite and crystalline silicon solar cells, can effectively absorb light with wavelengths from 300-1200 nm, exceeding the efficiency limit of single-junction cells.

[0105] Figure 2 and Figure 3 The images displayed are SEM images (surface and cross-section) of the perovskite / crystalline silicon multilayer film. The surface morphology test on the left shows that after depositing inorganic salts and coating organic salts on the textured surface of the crystalline silicon, the deposited perovskite layer completely covers the "pyramid" structure of the crystalline silicon, achieving conformal deposition. Simultaneously, the cross-sectional morphology test on the right also shows that the "pyramid" is completely covered by the perovskite layer deposited using this method, with no exposed pyramid tip to prevent leakage current.

[0106] Figure 4 The image shows a comparison of XRD patterns of the thin film before and after inorganic salt annealing. The bottom of the image represents the film before annealing, and the top represents the film after annealing. The comparison reveals a significant enhancement of the diffraction peak at 11.2° after annealing. Researching relevant literature indicates that this peak corresponds to the CsPb2X5 diffraction peak, suggesting that annealing can promote the transformation of the inorganic perovskite phase and establish the inorganic framework of the perovskite crystal structure.

[0107] Figure 5 The image shows the XRD pattern of the perovskite / crystalline silicon multilayer film. As can be seen from the image, there are no diffraction peaks for lead iodide, indicating that the coated organic salt reacted completely with the evaporated inorganic lead iodide, leaving no lead iodide residue. At the same time, the characteristic peaks of the perovskite photoactive phase (α phase) on different crystal planes are clearly visible, indicating that the perovskite film has good crystallinity.

[0108] In summary, the "intermediate annealing" in this invention targets the inorganic salt layer after vapor deposition, before it reacts with the organic salt. Its purpose is to alter the physical morphology of the inorganic salt (from dense to porous) to promote complete subsequent liquid-phase reactions. This is fundamentally different from annealing the final perovskite film (optimizing overall crystallization) or annealing other functional layers. The accumulation of impurities such as residual PbI2 during large-area fabrication is a recognized challenge, and existing technologies often address this through solution additives and post-treatment. This solution, starting with "pretreatment of inorganic salt reactants," provides a completely new technical approach.

[0109] This solution addresses the specific problem of conformal deposition on industrially produced micron-scale textured silicon wafers. Solution methods alone are insufficient for achieving the desired coverage, while evaporation methods are costly and inefficient. This solution is not a random combination; rather, it leverages the stepped coverage advantage of vacuum evaporation to construct the basic framework, and then utilizes the economic advantages of solution methods to complete the conversion reaction. This targeted combination, based on a deep understanding of the inherent advantages and disadvantages of different processes, is designed to solve specific problems in a particular scenario.

[0110] Furthermore, the superior performance achieved through the aforementioned experimental data is the result of the combined and mutually reinforcing effects of multiple steps in the technical solution, such as "intermediate annealing to optimize the reaction," "mixing process to achieve shape preservation," and "stable extraction of the interface system." The overall effect is better than the simple sum of the effects of each step, which is a synergistic effect.

[0111] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are used only for the convenience of describing the invention and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0112] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0113] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing a large-area perovskite thin film, characterized in that, Includes the following steps: Step 1: Provide a substrate; Step 2: An inorganic salt layer is prepared on the substrate by vacuum evaporation. Step 3: Perform a first annealing treatment on the inorganic salt layer at a temperature of 100~180℃ for 8~12 minutes. Step 4: Deposit an organic salt solution onto the inorganic salt layer after the first annealing treatment using a solution coating method, so that it reacts with the inorganic salt layer; Step 5: The reacted film is subjected to vacuum flash evaporation and a second annealing treatment in sequence. The annealing temperature is 80~120℃ and the annealing time is 18~22 minutes to form a perovskite light-absorbing layer.

2. The method for preparing a large-area perovskite thin film as described in claim 1, characterized in that, The inorganic salt layer comprises any one or a combination of two or more of lead halide, alkali metal halide, and inorganic metal lead halide, and the thickness of the inorganic salt layer is 250 nm to 400 nm.

3. The method for preparing a large-area perovskite thin film as described in claim 1, characterized in that, The organic salt solution comprises any one or a combination of two or more of ammonium halide salts, organic ammonium salts, and pseudohalogenated ammonium salts, and the concentration of the organic salt solution is 0.5~1.5M.

4. A large-area perovskite thin film, characterized in that, It is prepared by any one of claims 1 to 3 above.

5. A method for preparing a large-area calcium-titanium battery, characterized in that, Includes the following steps: Step 1: Provide a substrate and perform a cleaning pretreatment on the surface of the substrate; Step 2: Prepare a first hole transport layer on the substrate using physical vapor deposition. Step 3: A self-assembled monolayer solution is coated onto the first hole transport layer using a solution method, and a composite hole transport layer is formed after drying. Step 4: An inorganic salt layer is prepared on the composite hole transport layer by vacuum evaporation. Step 5: Perform a first annealing treatment on the inorganic salt layer; Step 6: Prepare the organic salt solution; Step 7: Coat the organic salt solution onto the inorganic salt layer after the first annealing treatment to form a perovskite wet film; Step 8: The perovskite wet film is subjected to vacuum flash drying and a second annealing treatment in sequence to form a perovskite light-absorbing layer; Step 9: Apply a passivation layer solution onto the perovskite light-absorbing layer using a solution method, and then perform annealing treatment to form a passivation layer; Step 10: Prepare an electron transport layer on the passivation layer by vacuum evaporation. Step 11: Prepare a hole blocking layer on the electron transport layer; Step 12: Prepare the transparent conductive electrode and the metal back electrode in sequence to complete the battery fabrication.

6. The method for preparing a large-area calcium-titanium battery as described in claim 5, characterized in that, In step S1, a heterogeneous crystalline silicon cell or a TOPCon crystalline silicon cell is used as the base cell; Before step 2, a step is also included in which a transparent conductive composite layer is prepared on the bottom battery by magnetron sputtering, wherein the sputtering power is 0.8~1.2KW and the thickness is 18~22nm; In step 2, the first hole transport layer is a nickel oxide layer, which is prepared by magnetron sputtering with a sputtering power of 0.8~1.2KW, a thickness of 10~15nm, and a process temperature of 180~220℃. In step 3, the self-assembled monolayer material is selected from MeO-2PACz, Me-4PACz, or 4PADCB, and is applied by a blade coating method and annealed at 80~120℃ for 8~12 minutes.

7. The method for preparing a large-area calcium-titanium battery as described in claim 5, characterized in that, In step S4, an inorganic salt layer is prepared by co-evaporation, wherein the evaporation thickness of lead iodide is 280~320nm, and the evaporation rate ratio of lead iodide, cesium halide and lead chloride is 10:1:

1. In step S5, the first annealing temperature is 100~180℃, and the annealing time is 8~12 minutes; In step S6, the solvent for the organic salt solution is ethanol; the organic salt includes formamidine iodide, formamidine bromide, and methylamine iodide or methylamine chloride; In step S8, the conditions for vacuum flash drying are as follows: the pressure is reduced to 8-12 Pa within 8-12 seconds and maintained for 8-12 seconds; the temperature of the second annealing treatment is 80-120℃ and the annealing time is 18-22 minutes.

8. The method for preparing a large-area calcium-titanium battery as described in claim 5, characterized in that, In step S9, the passivation layer solution is an isopropanol solution of piperazine monoiodine, and the annealing temperature is 80~120℃ for 4~6 minutes. In step S10, the electron transport layer is C 60 At a vacuum degree of 6×10 -4 Under Pa conditions, vapor deposition was carried out at a rate of 0.1~0.2 Å / s to a thickness of 18~22 nm.

9. The method for preparing a large-area calcium-titanium battery as described in claim 5, characterized in that, In step S11, the hole blocking layer is SnO2, prepared by atomic layer deposition, the cavity temperature is 70~90℃, TDMASn is used as the tin source, pure water is used as the oxygen source, the outlet temperature is 60~70℃, and the number of cycles is 70~90. In step S12, the transparent conductive electrode is an indium tin oxide layer, which is prepared by magnetron sputtering with a sputtering power of 0.8~1.2KW and a thickness of 18~22nm; the metal back electrode is made of copper or silver; when it is a copper electrode, it is prepared by magnetron sputtering; when it is a silver electrode, it is prepared by screen printing silver paste and then curing.

10. A large-area calcium-titanium battery, characterized in that, It is prepared by any one of claims 5 to 9 above.

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