Color curved surface photovoltaic tile and preparation method thereof

Abstract

The invention provides a colored curved-surface photovoltaic tile and a preparation method thereof.The colored curved-surface photovoltaic tile comprises photovoltaic power generation glass and high-transmittance curved-surface glass connected to the upper portion of the photovoltaic power generation glass, the photovoltaic power generation glass is of a plane structure, the high-transmittance curved-surface glass is of an upwards-protruding arc-shaped curved-surface structure, a cavity exists between the high-transmittance curved-surface glass and the photovoltaic power generation glass, and the high-transmittance curved-surface glass and the photovoltaic power generation glass are of an arc-shaped curved-surface structure; and a colored reflecting film layer is arranged on the inner surface or the outer surface of the high-transmittance curved glass. Through the innovative structure of compounding the high-transmittance curved glass and the planar photovoltaic power generation glass, photovoltaic light receiving surfaces are on the same plane, so that the photovoltaic power generation glass can receive light and generate power as uniformly as possible; meanwhile, the curved surface appearance effect of the photovoltaic tile is achieved through low-cost high-transmittance curved glass, and the problems that a flexible assembly is low in power generation efficiency and high in cost are solved; besides, the distributed Bragg reflection layer replaces a traditional color coating, the requirements of various colors and various color effects can be met, the light transmittance is higher (larger than or equal to 80%), and comprehensive breakthrough of colors, efficiency and cost is achieved.

Description

Technical Field

[0001] The present invention relates to the technical field of solar photovoltaic technology, and particularly to a colored curved photovoltaic tile and a preparation method thereof. Background Art

[0002] With the opening of the photovoltaic tile market, there is an increasing demand to use photovoltaic curved tiles to replace traditional barrel tiles on the roofs of ancient buildings and buildings with specific foreign styles. However, the conventional photovoltaic tiles on the market have the following defects: (1) Rigid photovoltaic modules cannot be bent: Conventional photovoltaic modules are all rigid, such as common monocrystalline silicon single-glass, double-glass modules, and thin-film double-glass modules on the market, which cannot be bent and are difficult to meet the bending requirements of curved tiles; even if photovoltaic modules such as ultra-thin crystalline silicon solar cells can be bent, the bending degree cannot meet the requirements of curved tiles. (2) Flexible photovoltaic modules have low power generation efficiency and high costs: Although special flexible modules such as copper indium gallium selenide can be bent, the sun can only shine on one angle of the curved tile, resulting in the inability to generate electricity for the entire photovoltaic tile, and the non-power generation part may affect the electrical performance output of the power generation part, resulting in unsatisfactory power generation efficiency, and the production cost of indium gallium selenide photovoltaic modules is high. (3) Single color or affecting power generation efficiency: Conventional photovoltaic tiles are all in the natural color of the photovoltaic modules and cannot meet the building's requirements for various appearance colors; or a colored coating is applied, but the light transmittance of the coating is poor (<60%), which has a greater impact on photovoltaic power generation and weakens the power generation performance of the photovoltaic tile itself.

[0003] Therefore, there is an urgent need in the market for a photovoltaic tile that can balance bending, power generation efficiency, cost, and color. Summary of the Invention

[0004] In view of the above-mentioned disadvantages of the prior art, the purpose of the present invention is to provide a colored curved photovoltaic tile and a preparation method thereof, which are used to solve the problems in the prior art that rigid photovoltaic modules cannot be bent, flexible photovoltaic modules have low power generation efficiency and high costs, and the color is single or affects power generation efficiency.

[0005] To achieve the above purpose and other related purposes, the present invention provides the following technical solutions: In the first aspect of the present invention, a colored curved photovoltaic tile is provided, which includes a photovoltaic power generation glass and a highly transparent curved glass connected above it. The photovoltaic power generation glass has a planar structure, and the highly transparent curved glass has an upwardly protruding arc-shaped curved surface structure. There is a cavity between the highly transparent curved glass and the photovoltaic power generation glass, and a colored reflective film layer is provided on the inner surface or the outer surface of the highly transparent curved glass.

[0006] During use, sunlight shines on the highly transparent curved glass. A small amount of light is reflected to make the photovoltaic tile produce color, and most of the light enters the interior of the highly transparent curved glass through transmission and evenly shines on the planar photovoltaic power generation glass to generate electric power.

[0007] The present invention simulates the curved surface appearance through highly transparent curved glass, avoiding direct bending of the photovoltaic power generation glass, reducing the process difficulty and cost, and the highly transparent curved glass can protect the photovoltaic power generation glass on the outside to ensure the stability during long-term use; meanwhile, a planar photovoltaic power generation glass is adopted, so that the photovoltaic light-receiving surface is on the same plane, enabling it to receive light and generate electricity as evenly as possible, and avoiding loss of power generation efficiency; while achieving diverse colors, the color reflective film layer ensures a high light transmittance and reduces the impact on power generation efficiency.

[0008] To ensure that the color reflective film layer has a high light transmittance while meeting the requirements of color and color effect, the color reflective film layer selects distributed Bragg reflection layers presenting different colors, and the distributed Bragg reflection layer is formed by alternately stacking high refractive index layers and low refractive index layers, which is used to selectively reflect target wavelength light and transmit light in other bands; and the light transmittance of the distributed Bragg reflection layer ≥ 80%.

[0009] The distributed Bragg reflection layer of the present invention is an optical phenomenon that realizes color effects through refractive index regulation, which can take into account both a high light transmittance (≥ 80%) and bright colors, without dyes or pigments, so there is no risk of color coating peeling off, and the color durability is better; applying it to colored photovoltaic tiles can effectively improve the color persistence of the photovoltaic tiles and ensure a sufficiently high light transmittance.

[0010] Furthermore, the thickness d of each high refractive index layer H =λ0 / 4n H , and the thickness d of each low refractive index layer L =λ0 / 4n L , where λ0 is the central wavelength of the target color, n H is the refractive index of the high refractive index layer material, and n L is the refractive index of the low refractive index layer material. Among them, the refractive index n of the high refractive index layer H ≥ 2.0, and the refractive index nL of the low refractive index layer ≤ 1.5.

[0011] Even further, the material of the high refractive index layer is selected from TiO2 or Si3N4, and the material of the low refractive index layer is selected from SiO2 or MgF2.

[0012] The number of layers of the distributed Bragg reflection layer directly determines its reflectivity, color saturation and light transmittance. Therefore, the high refractive index layer and the low refractive index layer are alternately stacked in 2 - 6 pairs; preferably 3 - 4 pairs. Controlling the number of alternately stacked layers can not only ensure that the light transmittance and reflectivity are within a suitable range, but also avoid stress cracking caused by excessive thickness.

[0013] Further, the high refractive index layer and the low refractive index layer are sequentially deposited on the surface of the high-transparency curved glass by magnetron sputtering or atomic layer deposition to form a distributed Bragg reflection layer.

[0014] Further, an encapsulation protection layer is provided on the outermost side of the distributed Bragg reflection layer, and the material of the encapsulation protection layer is selected from SiO2, Al2O3 or silicone resin. Among them, SiO2 has the best compatibility with the distributed Bragg reflection layer, reduces interface reflection, and is chemically inert, resistant to UV and humidity, and is suitable for long-term outdoor use; Al2O3 has higher density than SiO2 and excellent water and oxygen barrier performance; silicone resin has good flexibility, can buffer the stress deformation of the curved glass, and has a light transmittance > 95% and is resistant to UV aging.

[0015] Furthermore, the thickness of the encapsulation protection layer is 20 - 100 nm.

[0016] Preferably, the distributed Bragg reflection layer is provided on the inner surface of the high-transparency curved glass, and the low refractive index layer is first deposited on the inner surface of the high-transparency curved glass, so that the first deposited layer matches the refractive index of the glass (n = 1.5) to reduce the initial reflection loss.

[0017] In the second aspect of the present invention, a method for preparing a colored curved photovoltaic tile is provided, including the following steps: (1) Provide a high-transparency curved glass substrate, and sequentially deposit a low refractive index layer and a high refractive index layer on one side of the substrate by magnetron sputtering or atomic layer deposition to form a distributed Bragg reflection layer structure; (2) Deposit an encapsulation protection layer on the outside of the distributed Bragg reflection layer; (3) Assemble the high-transparency curved glass obtained in step (2) with a planar photovoltaic glass to form a cavity between the high-transparency curved glass and the photovoltaic glass, and leave a part of the space below the photovoltaic glass for overlapping with the lower tile.

[0018] Further, in step (1), the substrate is first ultrasonically cleaned and then the surface to be deposited of the substrate is subjected to plasma treatment. Among them, the substrate is ultrasonically cleaned with acetone, ethanol and deionized water in sequence; the substrate is subjected to polar plasma treatment with O2 or Ar plasma.

[0019] Further, in the magnetron sputtering process of step (1), the substrate uses a planetary rotation fixture to ensure that the thickness uniformity deviation of the film layer at each part of the high-transparency curved glass is ≤ ±3%.

[0020] Further, in the magnetron sputtering process of step (1): the vacuum degree ≤ 5×10 -6 Torr, the sputtering gas is Ar, and the substrate temperature is 100 - 200 °C.

[0021] Furthermore, when the desired color is gold or metallic, a 1-2 nm thick layer of Ag is sputtered on the outside of the distributed Bragg reflector layer and annealed to form nanoparticles approximately 20 nm in size, thereby enhancing the metallic luster. The encapsulation protective layer is deposited on the outside of the nano-Ag layer.

[0022] As described above, the colored curved photovoltaic tile and its preparation method of the present invention have the following beneficial effects: 1. The present invention uses an innovative structure that combines high-transmittance curved glass with flat photovoltaic power generation glass to ensure that the photovoltaic light-receiving surface is on the same plane, enabling it to receive light and generate electricity as evenly as possible. At the same time, the relatively low-cost high-transmittance curved glass achieves the curved appearance of photovoltaic tiles, avoiding the problems of low power generation efficiency and high cost of flexible components.

[0023] 2. The present invention uses a distributed Bragg reflector layer instead of the traditional color coating, which can meet the needs of various colors and various color effects, and has a higher light transmittance (≥80%), so that the photovoltaic glass can receive most of the light, ensuring the efficient power generation of this colored curved photovoltaic tile, and achieving a comprehensive breakthrough in color, efficiency and cost. It is especially suitable for the renovation of ancient buildings and the high-end building integrated photovoltaic market. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 Shown is a schematic structural diagram of a colored curved photovoltaic tile disclosed in an embodiment of the present invention.

[0025] Component number description 1. Photovoltaic glass; 2. High-transmittance curved glass; 3. Colored reflective film layer; 4. Cavity. DETAILED DESCRIPTION

[0026] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. It should be noted that the following embodiments and features in the embodiments can be combined with each other unless there is a conflict.

[0027] Example 1 See also Figure 1 This embodiment provides a colored curved photovoltaic tile, comprising a photovoltaic power generation glass 1 and a high-transmittance curved glass 2 connected thereto. The photovoltaic power generation glass is a planar structure, and the high-transmittance curved glass is an upwardly protruding arc-shaped curved structure. A cavity 4 is present between the high-transmittance curved glass and the photovoltaic power generation glass. The high-transmittance curved glass leaves some space below the photovoltaic power generation glass. A colored reflective film layer 3 is provided on the inner surface of the high-transmittance curved glass. The colored reflective film layer is a distributed Bragg reflector layer that presents a blue color.

[0028] Among them, the distributed Bragg reflection layer is deposited layer by layer on the inner surface of the highly transparent curved glass through a magnetron sputtering process, and the deposition parameters are as follows:

[0029] After testing, the reflectivity of the colored curved photovoltaic tile prepared in this embodiment is ≥90% (color rendering) at 450 nm, the transmittance is ≥90%, the color and transmittance change <3% after 1000 hours, and the power generation loss <5%.

[0030] Example 2 This embodiment provides a colored curved photovoltaic tile, which includes a photovoltaic power generation glass and a highly transparent curved glass connected above it. The photovoltaic power generation glass has a planar structure, the highly transparent curved glass has an upwardly protruding arc-shaped curved surface structure, there is a cavity between the highly transparent curved glass and the photovoltaic power generation glass, the highly transparent curved glass leaves a part of the space below the photovoltaic power generation glass, and a colored reflection film layer is provided on the inner surface of the highly transparent curved glass. The colored reflection film layer is a distributed Bragg reflection layer presenting green color.

[0031] Among them, the distributed Bragg reflection layer is deposited layer by layer on the inner surface of the highly transparent curved glass through a magnetron sputtering process, and the deposition parameters are as follows:

[0032] After testing, the reflectivity of the colored curved photovoltaic tile prepared in this embodiment is ≥92% (color rendering) at 550 nm, the transmittance is ≥85%, the color and transmittance change <5% after 1000 hours, and the power generation loss <5%.

[0033] Example 3 This embodiment provides a colored curved photovoltaic tile, which includes a photovoltaic power generation glass and a highly transparent curved glass connected above it. The photovoltaic power generation glass has a planar structure, the highly transparent curved glass has an upwardly protruding arc-shaped curved surface structure, there is a cavity between the highly transparent curved glass and the photovoltaic power generation glass, the highly transparent curved glass leaves a part of the space below the photovoltaic power generation glass, and a colored reflection film layer is provided on the inner surface of the highly transparent curved glass. The colored reflection film layer is a distributed Bragg reflection layer presenting golden color.

[0034] Among them, the distributed Bragg reflection layer is deposited layer by layer on the inner surface of the highly transparent curved glass through a magnetron sputtering process, and the deposition parameters are as follows:

[0035] After testing, the reflectivity of the colored curved photovoltaic tile prepared in this embodiment is ≥90% (color rendering) at 600 nm, the transmittance is ≥80%, the color and transmittance change <5% after 1000 hours, and the power generation loss <10%.

[0036] In summary, through the innovative structure of the composite of high-transparency curved glass and flat photovoltaic glass, the light-receiving surface of the photovoltaic cell is on the same plane, enabling it to receive light and generate electricity as evenly as possible. At the same time, the low-cost high-transparency curved glass achieves the curved appearance effect of the photovoltaic tile, avoiding the problems of low power generation efficiency and high cost of flexible components. In addition, the distributed Bragg reflector layer replaces the traditional color coating, which can meet the requirements of various colors and color effects, and has a higher light transmittance (≥80%), achieving a comprehensive breakthrough in color, efficiency, and cost. Therefore, the present invention effectively overcomes various disadvantages in the prior art and has high industrial utilization value.

[0037] Among them, the terms such as "upper", "lower", "left", "right", "front", "rear", "middle", and "one" cited in this specification are only for the convenience of clear description and are not used to limit the scope of implementation of the present invention. The change or adjustment of their relative relationships shall also be regarded as the scope of implementation of the present invention without substantial change in the technical content.

[0038] The above embodiments are only illustrative of the principles and effects of the present invention and are not used to limit the present invention. All equivalent modifications or changes made by those with ordinary knowledge in the technical field without departing from the spirit and technical ideas disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A colored curved photovoltaic tile, characterized in that, It includes a photovoltaic glass and a highly transparent curved glass connected above it. The photovoltaic glass has a planar structure, and the highly transparent curved glass has an upwardly protruding arc-shaped curved surface structure. There is a cavity between the highly transparent curved glass and the photovoltaic glass, and a color reflective film layer is provided on the inner surface or the outer surface of the highly transparent curved glass.

2. The colored curved photovoltaic tile according to claim 1, wherein The color reflective film layer is a distributed Bragg reflection layer, and the distributed Bragg reflection layer is formed by alternately stacking high refractive index layers and low refractive index layers.

3. The colored curved photovoltaic tile according to claim 2, characterized in that, The light transmittance of the distributed Bragg reflection layer is ≥80%.

4. The colored curved photovoltaic tile according to claim 2, wherein The thickness d of each high refractive index layer H = λ0 / 4n H , the thickness d of each low refractive index layer L = λ0 / 4n L ; Among them, λ0 is the central wavelength of the target color, n H is the refractive index of the high refractive index layer material, n L is the refractive index of the low refractive index layer material.

5. The colored curved photovoltaic tile according to claim 2, wherein The material of the high refractive index layer is selected from TiO2 or Si3N4, and the material of the low refractive index layer is selected from SiO2 or MgF2.

6. The colored curved photovoltaic tile according to claim 2, wherein The high refractive index layer and the low refractive index layer are alternately stacked 2 to 6 pairs.

7. The colored curved photovoltaic tile according to claim 2, wherein An encapsulation protection layer is provided on the outermost side of the distributed Bragg reflection layer, and the material of the encapsulation protection layer is selected from SiO2, Al2O3 or silicone resin.

8. The colored curved photovoltaic tile according to claim 2, wherein The distributed Bragg reflection layer is provided on the inner surface of the highly transparent curved glass, and the low refractive index layer is first deposited on the inner surface of the highly transparent curved glass.

9. A method for preparing a colored curved photovoltaic tile according to any one of claims 1 to 8, characterized in that, It includes the following steps: (1) Provide a highly transparent curved glass substrate, and sequentially deposit a low refractive index layer and a high refractive index layer on one side of the substrate by magnetron sputtering or atomic layer deposition to form a distributed Bragg reflection layer structure; (2) Deposit an encapsulation protection layer on the outside of the distributed Bragg reflection layer; (3) Assemble the highly transparent curved glass obtained in step (2) with a planar photovoltaic glass to form a cavity between the highly transparent curved glass and the photovoltaic glass.

10. The preparation method according to claim 9, characterized in that, In the magnetron sputtering process, the substrate uses a planetary rotation fixture, and the film thickness uniformity deviation of each part of the highly transparent curved glass is ≤±3%.

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