Cadmium telluride laminated full perovskite structure

Abstract

The invention relates to the field of photovoltaic building integration, and particularly discloses a cadmium telluride laminated full-perovskite structure. The structure is a novel building integrated photovoltaic curtain wall glass product, and efficient absorption and energy conversion from visible light to near infrared spectrum are realized by compounding the rigid cadmium telluride battery and the flexible perovskite battery in the curtain wall glass. The overall structure comprises nine layers of laminated design, namely ultra-white tempered glass, a PVB film, a cadmium telluride cell layer, a PVB film, a PET film, a POE film, a flexible perovskite cell layer, a PET backboard, a low-temperature PVB film and inner-layer ultra-white tempered glass. All layers of materials are firmly combined through a low-temperature and high-pressure kettle process, transparency and mechanical strength are kept, and weather resistance, impact resistance and acoustic performance are also considered. Compared with a single cadmium telluride battery, the power generation efficiency of the product is improved by 30%-40%, and the product is particularly suitable for curtain walls, daylighting roofs and building facades, can effectively relieve the problem of building energy consumption, and realizes energy conservation, emission reduction and green sustainable development.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of building integrated photovoltaics, and particularly relates to a cadmium telluride laminated full-perovskite structure. BACKGROUND

[0002] At present, cadmium telluride chips have gradually begun to popularize in building integrated photovoltaics (BIPV) products. The thickness of cadmium telluride thin film components is only a few microns, which is lighter in weight than traditional crystalline silicon components, has low load requirements on building structures, and is suitable for application in various building forms, such as curved curtain walls, irregular roofs, etc. Cadmium telluride thin films can still maintain high power generation efficiency in low light intensity environments (such as overcast days, early morning or evening), which is more in line with the daily lighting conditions of buildings. In addition, by adjusting the thickness or structure of the thin film, different light transmittance (from transparent to semi-transparent) can be achieved, which can not only meet the lighting needs of buildings, but also take into account the power generation function, and is particularly suitable for application in curtain walls and daylighting roofs, etc. However, cadmium telluride cells have bottlenecks in photoelectric conversion efficiency, and although the highest laboratory efficiency can reach more than 24%, they are still limited in mass production and large-area application.

[0003] At the same time, the application of perovskite chips in BIPV products is also in the stage of gradual popularization. The light transmittance of perovskite thin films can be flexibly controlled by material composition and film thickness, from fully transparent to opaque, so it can meet the diversified lighting needs of different parts of building curtain walls, daylighting roofs and sunshades, while maintaining the power generation function. In addition, perovskite cells can present a variety of colors by adjusting the material structure or adding colorants, solving the problem of single appearance of traditional photovoltaic components affecting the beauty of buildings, and improving the decorative nature of BIPV products.

[0004] At present, the efficiency of perovskite single-junction cells has broken through 27%, the theoretical limit efficiency of perovskite single-junction cells is 33%, and the theoretical efficiency of laminated cells can reach 45%, which is much higher than the efficiency of mass-produced crystalline silicon components on the market. In recent years, enterprises have continuously broken the efficiency record of laminated perovskite components, showing great application potential. In addition, its advantages of low cost, flexible process and diversified appearance make it very suitable for BIPV applications. However, perovskite cells also have problems such as insufficient stability, susceptibility to humidity and temperature, etc. Therefore, it is difficult to meet the dual requirements of efficiency and stability by relying on a single technology.

[0005] The laminated structure of cadmium telluride and perovskite can realize complementary absorption of the spectrum. The band gap of cadmium telluride is about 1.5 eV, mainly absorbing long-wave light, while perovskite has a wider band gap, suitable for absorbing short-wave light. The laminated structure of the two can cover a wider range of solar spectrum, improving the photoelectric conversion efficiency. At the same time, the mature process and stability of cadmium telluride can make up for the shortcomings of perovskite, while the flexibility and low cost advantages of perovskite improve the overall economy and adaptability.

[0006] In view of the deficiencies of existing single cadmium telluride or perovskite battery in efficiency, stability and application scenarios, the present application proposes a new type of cadmium telluride laminated full perovskite structure. Through reasonable hierarchical design and low-temperature PVB interlayer process, the rigid cadmium telluride is organically combined with the flexible perovskite, realizing spectral complementation, performance synergy and process adaptation. The present application can not only significantly improve the photoelectric conversion efficiency, but also ensure the stability and durability of the product in actual building applications, providing a new solution for the development of future high-efficiency BIPV. SUMMARY

[0007] In order to overcome the above-mentioned defects of the prior art, the present application proposes a cadmium telluride laminated full perovskite structure, which adopts a nine-layer laminated structure, including, in order, super-white tempered glass, PVB film, cadmium telluride battery layer, PVB film, PET film, POE film and flexible perovskite battery layer, PET backboard, low-temperature PVB film and inner layer super-white tempered glass. Through this structure design, spectral complementation absorption can be realized to improve the overall photoelectric conversion efficiency, and the mechanical properties and weather resistance of the whole can be improved through multiple protective materials, thereby meeting the multiple requirements of transparency, strength and long-term stability in building photovoltaic integration, to solve the problems raised in the above background technology.

[0008] To achieve the above-mentioned purposes, the present application provides the following technical solutions: A cadmium telluride laminated full perovskite structure, which adopts a nine-layer laminated structure, including, in order, super-white tempered glass, PVB film, cadmium telluride battery layer, PVB film, PET film, POE film and flexible perovskite battery layer, PET backboard, low-temperature PVB film and inner layer super-white tempered glass.

[0009] As a further scheme of the present application: the first layer is a tempered glass processed from super-white float glass. Its light transmittance reaches 91.5%, ensuring high transmittance of visible light; at the same time, the impact strength of the tempered glass after tempering treatment can reach 100~110MPa, thereby improving the safety and durability of the overall product.

[0010] As a further scheme of the present application: the second layer adopts low-temperature transparent PVB (polyvinyl butyral) film. As a interlayer material, the film plays the role of safety protection, impact resistance, anti-shattering and resistance to external penetration. PVB can also improve the stability and durability of the overall structure, and has good water resistance, ultraviolet resistance and aging resistance, effectively preventing water from entering the glass interlayer and avoiding internal fogging or corrosion.

[0011] As a further scheme of the present application: the third layer adopts ultra-white glass, the surface is plated with a TCO conductive film layer, and a cadmium telluride film layer is deposited thereon by magnetron sputtering. The film layer structure comprises: substrate → back contact layer → p-type CdTe absorption layer → n-type CdS window layer → TCO front electrode → anti-reflection layer. After the sunlight passes through the anti-reflection layer and the TCO layer, it is absorbed by the CdTe absorption layer to generate electron-hole pairs, and under the action of the built-in electric field of the CdTe / CdS heterojunction, charge separation is realized, and finally current output is formed through the electrode collection.

[0012] As a further scheme of the present application: the fourth layer adopts a low-temperature transparent PVB film, which has damping properties and can effectively reduce low-frequency noise and improve the indoor acoustic environment.

[0013] As a further scheme of the present application: the fifth layer adopts a PET film, which has excellent mechanical properties, a tensile strength of 40-70 MPa, a transparency of 85-90%, and good impact resistance and water vapor barrier ability.

[0014] As a further scheme of the present application: the sixth layer adopts a POE (polyolefin elastomer) film, and a flexible large-area perovskite thin film is deposited on the second surface thereof. The main structure of the perovskite battery includes a transparent conductive substrate, a hole transport layer, a perovskite absorption layer, an electron transport layer, and a back electrode. The preparation process includes: conductive glass cleaning, laser scribing (P1-P4), hole transport layer deposition, perovskite layer preparation (coating or evaporation), electron transport layer deposition, back electrode deposition, edge cleaning, and packaging. This layer can effectively absorb indoor visible light, and as a supplement to the cadmium telluride single-layer battery, it can improve the power generation efficiency by 30-40% on the original basis.

[0015] As a further scheme of the present application: the seventh layer adopts a PET layer, which is used as a photovoltaic backboard material and has good toughness and a breaking elongation of 50-300%, which can ensure the reliability of the product during long-term use.

[0016] As a further scheme of the present application: the eighth layer adopts a low-temperature transparent PVB film. When the multi-layer glass and the flexible material are stacked, this layer can absorb external impact energy and has the effect of bulletproof glass, and can maintain good flexibility in extreme weather conditions and reduce the risk of glass breakage.

[0017] As a further scheme of the present application: the ninth layer adopts a tempered glass processed from ultra-white float glass, which has a light transmittance of 91.50% and an impact strength of 100-110 MPa, further enhancing the overall performance of the product.

[0018] As a further scheme of the present application: the present application adopts a low-temperature high-pressure kettle process to laminate the above multi-layer structure. The process parameters include: (1) Vacuum section: vacuumizing before heating up; (2) Heating section: 40~50 DEG C, 0.3 MPa in the first stage; 80~90 DEG C, 0.75 MPa in the second stage; 100~105 DEG C, 1.0 MPa in the third stage; (3) Constant temperature section: 115~120 DEG C, 1.10 MPa; (4) Cooling section: gradually cooling to 45 DEG C, then exhausting and opening the autoclave.

[0019] As a further scheme of the application: the autoclave process parameters are preferably the parameters listed in Table 1.

[0020] Table 1

[0021] A cadmium telluride laminated full-perovskite structure is provided, which is a new type of building integrated photovoltaic (BIPV) curtain wall glass product. The product fully utilizes the complementary advantages of the two types of cells in spectral response through the laminated design of rigid cadmium telluride cells and flexible perovskite cells. The cadmium telluride chip mainly absorbs wavelengths ranging from 100 nm to 800 nm, and the perovskite chip mainly absorbs wavelengths ranging from 300 nm to 1200 nm. Under the premise of ensuring transparency and mechanical strength, the photoelectric conversion efficiency is significantly improved.

[0022] Under the condition of 0% light transmittance, the laminated structure of the application can improve the conventional photoelectric conversion efficiency by about 40%, which is much higher than the efficiency of single cadmium telluride chip or single perovskite chip. At the same time, under weak light conditions, the structure still maintains high output power and has good weak light adaptability.

[0023] As a further scheme of the application: the product can not only be used as a curtain wall and a daylighting roof, but also be applied to various parts of a building. For example: (1) Building curtain wall: installed in the outer facade in transparent or translucent form to realize the integration of lighting and power generation; (2) Daylighting roof: maintaining natural lighting inside the building while achieving efficient power generation; (3) Indoor partition or decorative glass: meeting the aesthetic requirements and supplementing part of the power demand; (4) Special application: through the use of multiple PVB interlayers to enhance impact resistance, the product can meet the requirements of bulletproof or high safety in building scenarios.

[0024] As a further scheme of the present application: the cadmium telluride laminated perovskite structure of the present application not only solves the problem of insufficient efficiency or poor stability of single battery in the prior art, but also takes into account the building aesthetics, energy saving and safety, and has broad market prospects and application value. The product of the present application has the following comprehensive advantages: (1) High efficiency: the spectral complementation of cadmium telluride and perovskite significantly improves the photoelectric conversion efficiency; (2) High stability: mature cadmium telluride process is adopted, combined with low-temperature PVB interlayer and PET / POE multi-layer protection, to ensure long-term stability; (3) High safety: double-layered tempered super-white glass and multi-layered PVB film design have excellent impact resistance; (4) High applicability: transparency can be adjusted, and it can be used flexibly in various building applications; (5) High promotion value: mature process, controllable cost, suitable for large-scale promotion.

[0025] Compared with the prior art, the cadmium telluride laminated perovskite structure of the present application has the advantages of higher efficiency, stronger stability, more reasonable structure, more mature process and wider application: (1) Higher efficiency: through the spectral complementation design of cadmium telluride and perovskite, the power generation efficiency is improved by 30%~40%, and the theoretical efficiency upper limit is significantly higher than that of single-junction battery.

[0026] (2) Stronger stability: combining the mature stability of cadmium telluride with the flexibility and low-cost potential of perovskite ensures the durability in outdoor environment.

[0027] (3) More reasonable structure: the design of rigid and flexible combination not only has firmness, but also avoids the problem of easy cracking, while maintaining high transparency.

[0028] (4) More mature process: low-temperature PVB lamination process is adopted, which is suitable for multi-layer materials, ensuring the feasibility of large-scale production.

[0029] (5) Wider application: the product can be widely used in BIPV scenes such as curtain wall and daylighting roof, taking into account aesthetics, lighting and power generation functions, achieving the goal of energy saving, environmental protection and green building. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 is a schematic diagram of the overall profile of the cadmium telluride laminated perovskite structure of the present application; Figure 2 is a schematic diagram of the structure of the cadmium telluride thin film battery layer.

[0031] Figure 3 is a schematic diagram of the structure of the flexible perovskite battery layer.

[0032] Figure 4 : Photograph of the outdoor surface of the product of this invention (cadmium telluride facing the light).

[0033] Figure 5 : An actual photograph of the interior surface of the product of this invention (the light-facing surface of the entire perovskite). Detailed Implementation

[0034] The following detailed description, in conjunction with the accompanying drawings and embodiments, illustrates a specific implementation of the cadmium telluride tandem perovskite structure proposed in this invention, so that those skilled in the art can understand and implement it accordingly.

[0035] Example 1, combined with Figures 1-4 As shown, Figure 1 It showcases a nine-layer structure from the outside in; Figure 2 The sequential arrangement of the substrate, back contact layer, p-type CdTe absorption layer, n-type CdS window layer, TCO front electrode, and antireflection layer is shown. Figure 3 The distribution of the transparent conductive substrate, hole transport layer, perovskite absorber layer, electron transport layer and back electrode is shown.

[0036] In this embodiment, the cadmium telluride stacked perovskite structure adopts a stacked structure of rigid cadmium telluride layer and flexible perovskite layer, consisting of nine layers in total, including ultra-clear tempered glass, PVB film, cadmium telluride battery layer, PVB film, PET film, POE film, flexible perovskite battery layer, PET backsheet, low-temperature PVB film, and inner ultra-clear tempered glass. The above layers are firmly bonded together through a low-temperature autoclave process to form a transparent, safe BIPV product with high-efficiency photoelectric conversion function.

[0037] First layer: Ultra-clear tempered glass, 3.2mm thick, light transmittance ≥91.5%, impact resistance 100~110MPa, providing high light transmittance and mechanical protection.

[0038] The second layer is a low-temperature transparent PVB interlayer film, 0.76mm thick, which provides safety protection, impact resistance, and resistance to damp heat, preventing glass shards from flying.

[0039] The third layer is a cadmium telluride thin-film battery layer, which consists of a TCO conductive film, a CdS window layer, a CdTe absorption layer, a back electrode, and an anti-reflection layer. It is prepared using a magnetron sputtering process.

[0040] The fourth layer is a low-temperature transparent PVB film, which has an acoustic damping effect and effectively isolates low- and mid-frequency noise.

[0041] Fifth layer: PET film, 0.15mm thick, which blocks moisture and enhances structural toughness and thermal stability.

[0042] The sixth layer is a POE buffer layer and a flexible perovskite solar cell layer with a thickness of 0.30 mm. It absorbs stress and deposits perovskite solar cells, absorbing the spectrum in the 300~1200 nm band.

[0043] The seventh layer is a PET backsheet layer, 0.15mm thick, which is weather-resistant and tough, ensuring long-term stable operation of the battery.

[0044] Eighth layer: Low-temperature transparent PVB film, 0.76mm thick, enhances impact resistance and can be made into bulletproof glass.

[0045] Ninth layer: Inner layer of ultra-clear tempered glass with a light transmittance of ≥91.5%, further enhancing overall strength and safety.

[0046] The process includes manual assembly, vacuum sealing and packaging, and autoclaving. During autoclaving, a vacuum is first created, followed by a three-stage heating process (40-50℃, 80-90℃, and 100-105℃), then held at 115-120℃ and 1.1MPa for 60 minutes. Finally, the temperature is gradually reduced to 45℃, and the autoclave is opened after venting. This process ensures a tight bond between the layers, preventing air bubbles and delamination.

[0047] Example 2 provides another specific implementation parameter for a cadmium telluride stacked perovskite structure, specifically including: a first layer of ultra-clear tempered glass; a second layer of 0.76mm PVB film; a third layer of cadmium telluride battery chip; a fourth layer of 0.76mm PVB film; a fifth layer of 0.15mm PET film; a sixth layer of 0.30mm POE film and flexible perovskite battery layer; a seventh layer of 0.15mm PET backsheet layer; an eighth layer of 0.76mm PVB film; and a ninth layer of inner ultra-clear tempered glass.

[0048] The lamination process parameters are as follows: Vacuum section: Evacuate for 1 minute before heating; Heating section: First stage 40℃~50℃, 0.3MPa, 20 minutes; Second stage 80℃~90℃, 0.75MPa, 40 minutes; Third stage 100℃~105℃, 1.0MPa, 40 minutes; Constant temperature section: 115℃~120℃, 1.10MPa, 60 minutes; Cooling section: Gradually reduce to 45℃.

[0049] I. Overall Stacked Structure The cadmium telluride multilayer perovskite structure of the present invention adopts a multilayer stacked design, comprising, in sequence: First layer: Tempered glass made from ultra-clear float glass; Second layer: 0.76mm low-temperature transparent PVB film; The third layer: cadmium telluride chip, including glass substrate, TCO conductive film, CdS window layer, CdTe absorption layer, back electrode and antireflection layer; Fourth layer: 0.76mm low-temperature transparent PVB film; Fifth layer: 0.15mm PET film; The sixth layer: a 0.30mm POE film, on which a flexible, large-area all-perovskite solar cell is deposited; Seventh layer: 0.15mm PET backing layer; Eighth layer: 0.76mm low-temperature transparent PVB film; Ninth layer: Tempered glass made from ultra-clear float glass.

[0050] II. Functions and Preparation of Each Layer (1) First layer: Ultra-clear tempered glass It has a thickness of 3.2mm, a light transmittance of 91.50%, and an impact strength of 100~110MPa. This layer serves as the light-facing surface, ensuring high light transmittance and good safety performance.

[0051] (2) Second layer: Low-temperature transparent PVB film With a thickness of 0.76mm, it is used for bonding between the glass and the battery layer, and has the functions of impact resistance, protection against shattering and splashing, and impermeability.

[0052] (3) Third layer: Cadmium telluride battery layer The structure was prepared by magnetron sputtering and consisted of: a substrate glass; a back contact layer; a p-type CdTe absorber layer (thickness 2~6μm); an n-type CdS window layer (thickness 50~100nm); a TCO front electrode layer; and an antireflection layer.

[0053] Working principle: Sunlight passes through the antireflection layer and the TCO front electrode layer into the CdTe absorption layer, generating electron-hole pairs. Under the action of the built-in electric field of the heterojunction, charge separation and collection are achieved, thereby outputting current.

[0054] (4) Fourth layer: Low-temperature transparent PVB film With a thickness of 0.76mm, it serves to provide sound insulation, prevent water seepage, and provide secondary reinforcement.

[0055] (5) Fifth layer: PET film With a thickness of 0.15mm, it has good transparency and barrier properties, effectively preventing moisture and oxygen from penetrating.

[0056] (6) Sixth layer: POE film and flexible perovskite battery POE membrane: 0.30mm thick, acts as a buffer, absorbs stress, and prevents interlayer cracking.

[0057] Flexible perovskite solar cells: The main structure includes a transparent conductive substrate, a hole transport layer, a perovskite absorber layer, an electron transport layer, and a back electrode.

[0058] Fabrication process: Cleaning of conductive substrate; laser scribing (P1); deposition of hole transport layer; preparation of perovskite layer (coating or evaporation); laser scribing (P2); deposition of electron transport layer; deposition of back electrode; laser scribing (P3, P4); encapsulation.

[0059] (7) Seventh layer: PET backing layer With a thickness of 0.15mm, it serves as a photovoltaic backsheet, enhancing weather resistance and toughness.

[0060] (8) Eighth layer: Low-temperature transparent PVB film With a thickness of 0.76mm, it absorbs impact energy when multiple layers of glass and flexible materials are stacked, thus improving overall safety.

[0061] (9) Ninth layer: Inner layer of ultra-clear tempered glass With a thickness of 3.2mm, a light transmittance of 91.50%, and an impact strength of 100~110MPa, it is used to further enhance the overall mechanical properties.

[0062] III. Lamination Process Flow The lamination process is carried out using a low-temperature autoclave. The specific steps are as follows: Vacuum section: Evacuate for 1 minute before heating to ensure no air remains between layers; Heating phase: First stage: 40℃~50℃, 0.3MPa, 20 minutes; Second stage: 80℃~90℃, 0.75MPa, 40 minutes; Third stage: 100℃~105℃, 1.0MPa, 40 minutes; Constant temperature range: 115℃~120℃, 1.10MPa, 60 minutes; Cooling section: Gradually reduce to 45℃, then open the vessel after venting.

[0063] The above process ensures a tight bond between layers, avoids defects such as bubbles and delamination, and guarantees the transparency and stability of the components.

[0064] The above description is merely a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A cadmium telluride stacked perovskite structure, characterized in that, The layers are, in sequence, super-white tempered glass, PVB film, cadmium telluride battery layer, PVB film, PET film, POE film, flexible perovskite battery layer, PET backboard, low-temperature PVB film, and inner layer super-white tempered glass.

2. A cadmium telluride multilayer full perovskite structure according to claim 1, wherein, The cadmium telluride laminated all-perovskite structure comprises a rigid cadmium telluride battery and a flexible perovskite battery structure.

3. The CdTe multilayer perovskite structure of claim 1, wherein, The cadmium telluride laminated all-perovskite structure is laminated by a low-temperature autoclave process.

4. The CdTe multilayer perovskite structure of claim 3, wherein, The low-temperature autoclave process comprises: (1) vacuum stage: vacuumizing before heating; (2) heating stage: 40-50℃, 0.3MPa in the first stage, 80-90℃, 0.75MPa in the second stage, and 100-105℃, 1.0MPa in the third stage; (3) constant temperature stage: 115-120℃, 1.10MPa; (4) cooling stage: gradually cooling to 45℃, then exhausting and opening the autoclave.

5. The CdTe multilayer perovskite structure of claim 1, wherein, The first layer is tempered glass processed from super-white float glass; the second layer is low-temperature transparent PVB film; the third layer is cadmium telluride battery layer comprising cadmium telluride chips; the fourth layer is low-temperature transparent PVB film; the fifth layer is PET film; the sixth layer is POE film on which flexible large-area all-perovskite tandem solar cells are deposited; the seventh layer is PET backboard layer; the eighth layer is low-temperature transparent PVB film; and the ninth layer is tempered glass processed from super-white float glass.

6. A cadmium telluride multilayer full perovskite structure according to claim 5, wherein The low-temperature transparent PVB film has a thickness of 0.76mm.

7. A cadmium telluride multilayer perovskite structure according to claim 5, wherein, The PET film has a thickness of 0.15mm, and the POE film has a thickness of 0.30mm.

8. The CdTe multilayer perovskite structure of claim 1, wherein, The super-white tempered glass has a light transmittance of 91.50% and an impact strength of 100-110MPa.

9. The CdTe multilayer perovskite structure of claim 1, wherein, The cadmium telluride battery layer is prepared by a magnetron sputtering process.

10. The CdTe multilayer perovskite structure of claim 1, wherein, The flexible perovskite battery layer is prepared by a coating or evaporation process.

Images