Photovoltaic glass, preparation method thereof and photovoltaic module

Abstract

The invention discloses photovoltaic glass, a preparation method thereof and a photovoltaic module, and the photovoltaic glass comprises a glass substrate which comprises a first side and a second side which are opposite to each other; the glass anti-reflection layer is located on the first side of the glass substrate; the porosity of the glass anti-reflection layer is increased in the direction away from the glass substrate; the closed-pore layer comprises a plurality of nano particles and covers one side, away from the glass substrate, of the glass anti-reflection layer, and the particle size of the nano particles is larger than the aperture of the pore structure of the surface, in contact with the closed-pore layer, in the glass anti-reflection layer; or the closed-pore layer comprises a silicon-containing cross-linked structure which is cross-linked with at least part of the pore structure of the glass anti-reflection layer. In the application, along the direction away from the glass substrate, the porosity of the glass anti-reflection layer is increased, and the transmittance of the photovoltaic glass is improved.

Description

Technical Field

[0001] This application belongs to the field of photovoltaic technology, specifically relating to a photovoltaic glass, its preparation method, and a photovoltaic module. Background Technology

[0002] As a key component of photovoltaic modules, the performance of photovoltaic glass has a decisive impact on the performance of photovoltaic modules, among which the transmittance index directly affects the power of photovoltaic modules.

[0003] Existing photovoltaic glass has poor transmittance and still suffers from significant optical loss. Summary of the Invention

[0004] This application aims to provide a photovoltaic glass, a method for preparing the same, and a photovoltaic module, thereby addressing at least one of the problems related to the poor transmittance of photovoltaic glass.

[0005] In a first aspect, embodiments of this application propose a photovoltaic glass, comprising: A glass substrate, along the direction of its thickness, includes opposing first and second sides; A glass antireflective layer is located on a first side of the glass substrate; the porosity of the glass antireflective layer increases along the direction away from the glass substrate; A closed-pore layer comprising a plurality of nanoparticles covering the side of the glass antireflective layer away from the glass substrate, wherein the particle size of the nanoparticles is larger than the pore size of the pore structure of the surface of the glass antireflective layer in contact with the closed-pore layer; or, the closed-pore layer comprising a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflective layer.

[0006] In this application, firstly, the photovoltaic glass, based on the glass substrate, also has a glass anti-reflective layer. Along the direction away from the glass substrate, the porosity of the glass anti-reflective layer increases, improving the transmittance of the photovoltaic glass and reducing optical loss. Secondly, the nanoparticles of the closed-pore layer covering the glass anti-reflective layer have a larger particle size than the pore size of the surface of the glass anti-reflective layer in contact with the closed-pore layer. Therefore, the nanoparticles of the closed-pore layer do not block the pore structure of the glass anti-reflective layer. Thus, the closed-pore layer has virtually no impact on the transmittance of the glass anti-reflective layer, maintaining the good transmittance of the photovoltaic glass. It also protects the glass anti-reflective layer, preventing moisture and other substances from penetrating into the photovoltaic glass and photovoltaic module, improving the weather resistance of the photovoltaic glass. The silicon-containing cross-linked structure can act as a seal for at least part of the pore structure of the glass anti-reflective layer, preventing moisture and other substances from penetrating into the photovoltaic glass and photovoltaic module, thus improving the weather resistance of the photovoltaic glass. Thirdly, both the glass anti-reflective layer and the glass substrate are made primarily of glass, making the process of forming the photovoltaic glass relatively simple and appropriately reducing costs. In summary, this application not only improves the transmittance of photovoltaic glass and reduces optical loss, but also enhances the weather resistance of photovoltaic glass, while the process is relatively simple and the cost is low.

[0007] In some embodiments, the pore size of the antireflective layer is increased along the direction away from the glass substrate, and the antireflective layer is integrally formed with the glass substrate.

[0008] In some embodiments, the closed-pore layer is the plurality of nanoparticles, and the porosity of the closed-pore layer is greater than or equal to the porosity of the surface in the glass antireflective layer that is in contact with the closed-pore layer.

[0009] In some embodiments, the first surface of the photovoltaic glass is one surface of the closed-cell layer, and the hardness of the first surface of the photovoltaic glass is greater than or equal to 3H.

[0010] In some embodiments, the thickness of the closed-cell layer is less than the thickness of the glass antireflective layer. In some embodiments, the ratio of the thickness of the closed-cell layer to the thickness of the glass antireflective layer is greater than or equal to 1 / 2 and less than or equal to 2 / 3.

[0011] In some embodiments, the nanoparticles include: hollow nanospheres, and / or, nanoparticles and organic matter attached to at least a portion of the nanoparticles; The hollow nanospheres include at least one of the following: silicon dioxide hollow nanospheres, titanium dioxide hollow nanospheres, and magnesium fluoride hollow nanospheres; The nanoparticles include at least one of the following: alumina particles, silicon nitride particles, carbon nitride particles, boron carbide particles, silicon carbide particles, and diamond particles; the organic material is selected from: polyoxyethylene-polyoxypropylene copolymer, polyoxypropylene-polyoxyethylene copolymer, hexadecyltrimethylammonium bromide, polyethylene glycol, methoxy polyethylene glycol, and polystyrene. Gathering (2) Vinylpyridine, polystyrene Gather (4) Vinylpyridine, polystyrene Polymethyl methacrylate and polystyrene At least one of the following: polyethylene oxide.

[0012] In some embodiments, the porosity of the closed-cell layer is less than or equal to the porosity of the surface in the glass antireflective layer that is in contact with the closed-cell layer.

[0013] In some embodiments, the photovoltaic glass further includes a weather-resistant layer located on the side of the closed-cell layer opposite to the glass substrate, wherein the hardness of the photovoltaic glass is greater than or equal to 4H, and the thickness of the weather-resistant layer is less than or equal to 50nm.

[0014] In some embodiments, the weather-resistant layer includes at least one of a silicon dioxide layer, an aluminum-doped silicon oxide nanolayer, an aluminum oxide layer, and a zirconium oxide layer.

[0015] In some embodiments, the end of the silicon-containing crosslinked structure away from the porous structure of the glass antireflective layer contains an amino functional group and / or a methyl functional group.

[0016] In some embodiments, the photovoltaic glass further includes: a light-converting material; The light-converting material fills at least one porous structure in the glass antireflective layer; and / or The phototransfer material fills the spaces between adjacent nanoparticles to form a porous structure; and / or, the nanoparticles contain a porous structure, and the phototransfer material fills the porous structure of the nanoparticles.

[0017] In some embodiments, the light-converting material includes: Sm 3+ Er 3+ Eu 3+ Y 3+ At least one of them.

[0018] Secondly, embodiments of this application propose a photovoltaic module, comprising: Battery string array; the battery string includes several battery cells; An encapsulating film is located on at least one side of the battery string array; In any of the aforementioned photovoltaic glasses, the photovoltaic glass is located on the side of the encapsulating film away from the battery string array, the glass antireflection layer is disposed on the first side of the glass substrate away from the encapsulating film, the refractive index of the glass antireflection layer decreases along the direction away from the glass substrate, and the refractive index of the photovoltaic glass is less than the refractive index of the encapsulating film.

[0019] In some embodiments, the hardness of the surface of the photovoltaic glass away from the encapsulating film is greater than the hardness of the surface of the photovoltaic glass close to the encapsulating film.

[0020] In some embodiments, the surface roughness of the photovoltaic glass near the encapsulating film is less than the surface roughness of the photovoltaic glass away from the encapsulating film.

[0021] In some embodiments, the thickness of the anti-reflective layer is 1% × 10⁻⁶ of the thickness of the photovoltaic glass. -3 Up to 60%×10 -3 .

[0022] Thirdly, embodiments of this application propose a method for preparing photovoltaic glass, comprising: A glass substrate is provided, including opposing third and fourth sides along the direction of its thickness; The third side of the glass substrate is etched to form a glass antireflection layer on the third side; the porosity of the glass antireflection layer increases in the direction away from the glass substrate. A closed-cell layer is deposited on the glass antireflective layer; the closed-cell layer includes a plurality of nanoparticles, the particle size of which is larger than the pore size of the pore structure of the surface of the glass antireflective layer in contact with the closed-cell layer; or, the closed-cell layer includes a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflective layer.

[0023] The above-mentioned photovoltaic glass preparation method and photovoltaic module have the same or similar beneficial effects as photovoltaic glass, and will not be repeated here to avoid repetition. Attached Figure Description

[0024] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which: Figure 1 , Figure 3 , Figure 7 The following are schematic diagrams illustrating the structures of three types of photovoltaic glass in embodiments of the present invention; Figure 5 , Figure 8 This is a partial SEM image of the photovoltaic glass in this application; Figure 2 and Figure 4 This is a graph showing the refractive index variation at different locations in the antireflective layer of the photovoltaic glass in this application; Figure 6 and Figure 9 This is a comparison curve of the light transmittance or transmittance of the photovoltaic glass and its semi-finished products in this application; Figure 10 This is the intensity curve of the excitation spectrum light within 400nm of the photovoltaic glass containing the light conversion material in this application; Figure 11 This application shows the emission spectrum curve of the photovoltaic glass containing light-converting materials excited by light at around 315nm. Figure 12 This is a comparison chart of the transmittance curves of the photovoltaic glass of this application and the photovoltaic glass of the comparative example; Figure 13 This is a comparative graph showing the transmittance curves of photovoltaic glass and its semi-finished products.

[0025] Figure label: 11-Glass substrate, 12-Glass antireflective layer, 121-Porous structure of glass antireflective layer, 13-Closed-cell layer, 1311-Nano hollow spheres, 14-Weather-resistant layer. Detailed Implementation

[0026] The embodiments of this application will now be described in detail. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

[0027] This application provides a photovoltaic glass that can serve as a cover plate or a backsheet for a photovoltaic module. The photovoltaic module includes a cell string array, where each cell string comprises several cells. During normal operation, the side of each cell that primarily absorbs light is its light-facing side, while the back-light side is opposite to the light-facing side. The cover plate is located on the light-facing side of the cell string array or cell string, and the backsheet is located on the back-light side of the cell string array or cell string.

[0028] Reference Figure 1 , Figure 3 , Figure 5 , Figure 7 and Figure 8 The photovoltaic glass provided in this application includes: a glass substrate 11, a glass anti-reflective layer 12, and a closed-cell layer 13. The glass substrate 11, along its thickness direction L, includes opposing first and second sides. For example, Figure 1 , Figure 3 , Figure 5 , Figure 7 and Figure 8 In the glass substrate 11, the upper side is its first side, and the lower side is its second side. A glass antireflective layer 12 is located on the first side of the glass substrate 11; the glass antireflective layer 12 contains a plurality of porous structures 121. It should be noted that SEM mentioned in this application refers to scanning electron microscopy. (See reference...) Figure 1 , Figure 3 , Figure 5 , Figure 7 and Figure 8 Along the direction away from the glass substrate 11, the porosity of the glass antireflection layer 12 increases. The porosity of the glass antireflection layer 12 is the percentage of the volume of the pore structure 121 in the glass antireflection layer 12 to the total volume of the glass antireflection layer 12 in its natural state. The increased porosity of the glass antireflection layer 12 along the direction away from the glass substrate 11 means that the transmittance of the glass antireflection layer 12 increases, or the refractive index of the glass antireflection layer 12 decreases, thereby improving the transmittance of the photovoltaic glass and reducing optical losses. Furthermore, since both the glass antireflection layer 12 and the glass substrate 11 are primarily made of glass, the process for forming the photovoltaic glass is relatively simple, which can appropriately reduce costs.

[0029] More specifically, the porosity of the glass antireflection layer 12 significantly affects its refractive index and transmittance; the higher the porosity of the glass antireflection layer 12, the lower its refractive index and the higher its transmittance. For example, Figure 2 and Figure 4 In both types of glass antireflective layers, the horizontal axis represents the wavelength of light in nanometers, and the vertical axis represents the refractive index at different locations of the glass antireflective layer in units of 1. Each curve represents the refractive index distribution at different locations of the glass antireflective layer 12 at the corresponding wavelength. The curves from top to bottom or from away from the horizontal axis to closer to the horizontal axis represent the refractive index distribution at different locations of the glass antireflective layer 12 at the corresponding wavelength along the direction away from the glass substrate 11. Figure 2 and Figure 4 In the diagram, curves that are lower or closer to the horizontal axis represent the refractive index distribution at the corresponding wavelength for locations further away from the glass substrate, while curves that are higher or further away from the horizontal axis represent the refractive index distribution at the corresponding wavelength for locations closer to the glass substrate. The curve that is highest or furthest from the horizontal axis can be considered the refractive index distribution of the glass substrate at the corresponding wavelength. For... Figure 1 , Figure 3 , Figure 5 , Figure 7 and Figure 8 Along the direction away from the glass substrate 11, the porosity of the antireflective layer 12 increases, then refer to Figure 2 and Figure 4Along the direction opposite to the glass substrate 11, the refractive index of the antireflective layer 12 decreases. For example, Figure 2 In the wavelength range that the solar cell can absorb (e.g., 320-1100 nm), the refractive index of the glass antireflection layer 12 on the side opposite to the glass substrate 11 is less than or equal to 1.4. Figure 4 In this application, within the wavelength range that the solar cell can absorb (e.g., 320-1100 nm), the refractive index of the antireflective layer 12 on the side opposite to the glass substrate 11 is less than or equal to 1.1. All refractive indices mentioned throughout this application refer to the refractive index of a specific structure within the wavelength range that the solar cell can absorb (e.g., 320-1100 nm). Specific refractive index measurements can be performed using existing methods. In photovoltaic glass and photovoltaic modules, the refractive index of each structure can be measured directly within the photovoltaic glass and photovoltaic module, or the photovoltaic glass or photovoltaic module can be disassembled and the refractive index of the corresponding structure measured individually.

[0030] More specifically, the inventors of this application, through analysis of the light loss of photovoltaic glass or photovoltaic modules, have determined that the loss mainly falls into two categories: parasitic absorption within the photovoltaic glass itself and reflection loss occurring at the photovoltaic glass interface when light is incident. Currently, the parasitic absorption of photovoltaic glass has reached a very low level, essentially approaching zero. Therefore, the main way to further improve the transmittance of photovoltaic glass is to reduce its reflection. In this application, an anti-reflection layer is provided on top of the glass substrate. Along the direction away from the glass substrate, the porosity of the anti-reflection layer increases, achieving a roughly gradual decrease in refractive index from the photovoltaic glass interface to the air interface. This reduces light reflection, improves the transmittance of the photovoltaic glass, and lowers optical losses.

[0031] It should be noted that in this application, the glass antireflective layer 12 is located on the first side of the glass substrate 11. The porosity distribution of the glass antireflective layer 12 along the direction away from the glass substrate 11, and the determination of the porosity of the glass antireflective layer 12, can be performed using methods such as gas adsorption. In this application, the determination of the porosity of other structures can also be done in a similar manner, or by referring to the porosity determination methods of related technologies. This application is not limited to the exemplary methods. Here, gas adsorption refers to using methods such as low-temperature nitrogen adsorption to measure the volume of the pore structure of the glass antireflective layer 12 in order to further determine the porosity of the glass antireflective layer 12.

[0032] It should be noted that, along the direction away from the glass substrate, the porosity of the glass antireflective layer can increase linearly, exponentially, or otherwise, without any specific limitation.

[0033] Reference Figure 3 and Figure 5The closed-pore layer 13, comprising a number of nanoparticles, covers the side of the glass antireflective layer 12 away from the glass substrate 11. The particle size of the nanoparticles is larger than the pore size of the pore structure 121 on the surface of the glass antireflective layer 12 that is in contact with the closed-pore layer 13. Therefore, the nanoparticles of the closed-pore layer 13 will not block the pore structure 121 of the glass antireflective layer 12. Thus, the closed-pore layer 13 will not significantly affect the transmittance of the glass antireflective layer 12, maintaining the good transmittance of the photovoltaic glass. It can also protect the glass antireflective layer 12, preventing moisture and other substances from penetrating into the photovoltaic glass and the interior of the photovoltaic module, thereby improving the weather resistance of the photovoltaic glass.

[0034] Reference Figure 7 and Figure 8 The closed-cell layer 13 includes a silicon-containing cross-linked structure formed with at least a portion of the pore structure 121 of the glass anti-reflection layer 12. The silicon-containing cross-linked structure can act as a seal for at least a portion of the pore structure of the glass anti-reflection layer 12, preventing water vapor and other substances from penetrating into the photovoltaic glass and the interior of the photovoltaic module, thereby improving the weather resistance of the photovoltaic glass.

[0035] In some embodiments, refer to Figure 1 , Figure 3 , Figure 5 , Figure 7 and Figure 8 Along the direction away from the glass substrate 11, the pore size of the pore structure 121 of the glass antireflection layer 12 increases. By increasing the pore size of the pore structure 121, the porosity of the glass antireflection layer 12 is easily increased along the direction away from the glass substrate 11.

[0036] In some embodiments, the glass antireflective layer is formed by glass etching integrally with the glass substrate, or in other words, the glass antireflective layer and the glass substrate are an integral structure. On the one hand, the photovoltaic glass has higher mechanical strength; on the other hand, the glass antireflective layer and the glass substrate are made of the same main material, namely the same glass. No additional adhesive or other steps are required between the glass antireflective layer and the glass substrate, making the process of forming photovoltaic glass relatively simple and reducing costs appropriately.

[0037] It should be noted that the glass antireflective layer can be a structure with gradually changing porosity and pore size formed by acid etching, alkaline etching, nanoimprinting, laser etching, etc., which is integral with the glass substrate, resulting in a gradual change in the refractive index gradient of the glass antireflective layer.

[0038] In some embodiments, the pore size of the pore structure 121 in the glass antireflection layer 12 can be 2-40 nm, referring to... Figure 5 and Figure 8The thickness H1 of the glass antireflection layer 12 can be 30-1000nm. The porosity of the glass antireflection layer 12 on the side away from the glass substrate 11 is adjusted by controlling the thickness of the glass antireflection layer 12 and the pore size of the pore structure on the side of the glass antireflection layer 12 away from the glass substrate 11. This, in turn, adjusts the refractive index or transmittance of the glass antireflection layer 12 on the side away from the glass substrate 11. Therefore, once the porosity of the glass antireflection layer 12 on the side away from the glass substrate 11 is determined, the refractive index or transmittance of the glass antireflection layer 12 on the side away from the glass substrate 11 is roughly determined.

[0039] It should be noted that in this application, the scheme for the closed-pore layer 13 comprising several nanoparticles covering the side of the glass antireflective layer 12 facing away from the glass substrate 11, wherein the particle size of the nanoparticles is larger than the pore size of the pore structure 121 on the surface of the glass antireflective layer 12 in contact with the closed-pore layer 13, mainly includes two sub-schemes. The first sub-scheme is: the porosity of the side of the glass antireflective layer 12 facing away from the glass substrate 11 is slightly smaller, resulting in a slightly larger transmittance or refractive index on the side of the glass antireflective layer 12 facing away from the glass substrate, referring to... Figure 2 The refractive index of the glass antireflective layer 12 on the side facing away from the glass substrate is less than or equal to 1.4, not yet close to 1.0. Therefore, the transmittance of the photovoltaic glass can be considered to have room for improvement. Thus, the porosity of the closed-cell layer 13 can be greater than or equal to the surface porosity of the glass antireflective layer 12 in contact with it. This means that the closed-cell layer 13 further expands the porosity gradient on the side of the glass antireflective layer 12 facing away from the glass substrate, further reducing the refractive index and further improving the transmittance of the photovoltaic glass. Furthermore, the closed-cell layer 13 can also protect the glass antireflective layer 12, preventing moisture and other substances from penetrating into the photovoltaic glass and photovoltaic modules, thus improving the weather resistance of the photovoltaic glass. The second sub-scheme is as follows: The porosity of the glass antireflective layer 12 on the side facing away from the glass substrate 11 is larger, and the refractive index on the side of the glass antireflective layer 12 facing away from the glass substrate is already very small. (Referring to...) Figure 4 The refractive index of the glass antireflective layer 12 on the side facing away from the glass substrate is less than or equal to 1.1, and approximately close to 1.0. For example, the refractive index of the glass antireflective layer 12 on the side facing away from the glass substrate 11 can be 1.2, 1.18, 1.15, 1.12, 1.1, 1.09, 1.07, 1.05, or 1.02. The space for further reduction in refractive index is very small. Therefore, the porosity of the closed-cell layer 13 is approximately equal to or less than the surface porosity of the glass antireflective layer 12 in contact with the closed-cell layer 13. This means that the closed-cell layer 13 maintains a porosity gradient on the side of the glass antireflective layer 12 facing away from the glass substrate. The closed-cell layer 13 does not affect the higher transmittance of the glass antireflective layer 12 on the side facing away from the glass substrate. Furthermore, the closed-cell layer 13 can protect the glass antireflective layer 12, preventing moisture and other substances from penetrating into the photovoltaic glass and photovoltaic module, thus improving the weather resistance of the photovoltaic glass. The two sub-schemes mentioned above will be described in detail below.

[0040] against Figure 2 In the corresponding first sub-scheme, the closed-pore layer 13 is composed of the aforementioned nanoparticles. The porosity of the closed-pore layer 13 is greater than or equal to the porosity of the surface of the glass antireflective layer 12 in contact with the closed-pore layer 13. The closed-pore layer 13 further expands the porosity gradient on the side of the glass antireflective layer 12 away from the glass substrate, further reducing the refractive index and further improving the transmittance of the photovoltaic glass. For example, the refractive index of the side of the closed-pore layer 13 away from the glass substrate can be 1.4, 1.35, 1.3, 1.25, 1.2, 1.15, 1.1, 1.05, or 1.02.

[0041] against Figure 2 In the corresponding first sub-scheme, the closed-pore layer 13 consists of the aforementioned nanoparticles. The thickness of the closed-pore layer 13 can be greater than or equal to the thickness of the glass antireflective layer 12, thus providing material support for achieving a larger porosity in the closed-pore layer 13. For example, regarding... Figure 2 In the corresponding first sub-scheme, the closed-pore layer 13 is composed of the aforementioned nanoparticles, and the thickness of the closed-pore layer 13 can be 60-160nm. For example, the thickness of the closed-pore layer 13 can be 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, 150nm, or 160nm. The thickness of the glass antireflection layer 12 can be 50-150nm. For example, the thickness of the closed-pore layer 13 can be 50nm, 60nm, 70nm, 80nm, 90nm, 100nm, 110nm, 120nm, 130nm, 140nm, or 150nm.

[0042] against Figure 2 In the corresponding first sub-scheme, the closed-pore layer 13 consists of the aforementioned nanoparticles, which can increase transmittance. In some embodiments, the closed-pore layer 13 can also close pores, improve weather resistance, and increase hardness. The closed-pore layer 13 directly serves as a weather-resistant layer. Alternatively, the photovoltaic glass includes a first surface and a second surface, which are opposite each other in their thickness direction. In the photovoltaic glass, the closed-pore layer is the outermost layer. The first surface of the photovoltaic glass is one surface of the closed-pore layer 13. The hardness of the first surface of the photovoltaic glass is greater than or equal to 3H. A hardness greater than or equal to 3H refers to the Mohs hardness of the first surface. A higher hardness of the first surface of the photovoltaic glass can protect the anti-reflective layer 12, preventing moisture and other substances from entering the photovoltaic glass or photovoltaic module through the porous structure of the anti-reflective layer 12, thus improving the performance and lifespan of the photovoltaic glass or photovoltaic module. For example, the hardness of the first surface of the photovoltaic glass can be 3H, 4H, 5H, 6H, 7H, etc. It should be noted that the photovoltaic glass described here is used in photovoltaic modules, and the first surface of the photovoltaic glass is the surface of the photovoltaic glass that is away from the encapsulating film.

[0043] It should be noted that, when the photovoltaic glass has already been used in photovoltaic modules, the hardness of the first surface of the photovoltaic glass referred to here can refer to the hardness of the side of the photovoltaic glass away from the encapsulating film, measured directly without disassembling the photovoltaic module.

[0044] against Figure 2 In the corresponding first sub-scheme, the closed-cell layer 13 is composed of the aforementioned nanoparticles. The porosity of the closed-cell layer 13 is greater than or equal to the porosity of the surface in the glass anti-reflection layer 12 that is in contact with the closed-cell layer 13. In this photovoltaic glass, the closed-cell layer 13 itself has certain weather resistance characteristics. The outer side of the closed-cell layer 13 does not need to be provided with a weather-resistant layer, which can simplify the structure of the photovoltaic glass and reduce the cost of the photovoltaic glass.

[0045] In some embodiments, for Figure 2 In the corresponding first sub-scheme, the nanoparticles have a particle size of 10-40 nm, which matches the porosity, transmittance, and refractive index required by the closed-pore layer 13. The pore size of the glass antireflection layer 12 has a pore structure of 2-10 nm, which matches the porosity, transmittance, and refractive index required by the glass antireflection layer 12. Simultaneously, the nanoparticle size is relatively larger than the pore size of the pore structure. The nanoparticles of the closed-pore layer 13 will not basically fill the pore structure of the glass antireflection layer 12, but will mainly cover the surface of the glass antireflection layer 12. This will not have a significant adverse effect on the transmittance of the glass antireflection layer 12, and will enhance the porosity gradient along the direction away from the glass substrate 11 in the glass antireflection layer 12, further improving the transmittance performance of the photovoltaic glass.

[0046] For example, targeting Figure 2 In the corresponding first sub-scheme, the pore size of the glass antireflective layer 12 can be 2nm, 3nm, 4nm, 5nm, 6nm, 7nm, 8nm, 9nm, or 10nm. For example, for... Figure 2 The corresponding first sub-scheme allows for nanoparticle sizes of 10nm, 15nm, 18nm, 20nm, 22nm, 25nm, 27nm, 30nm, 33nm, 35nm, 39nm, and 40nm.

[0047] It should be noted that, in this application, the pore size of the glass antireflection layer 12 can refer to the pore size of a single pore structure or the arithmetic mean of the pore sizes of two or more pore structures. The particle size of the nanoparticles can refer to the particle size of a single nanoparticle or the arithmetic mean of the particle sizes of two or more nanoparticles. The particle size of the nanoparticles affects the size of the pore structure between adjacent nanoparticles, thereby affecting the porosity, transmittance, and refractive index of the layer containing the nanoparticles. Therefore, the desired porosity, transmittance, and refractive index can be obtained by adjusting the particle size of the nanoparticles.

[0048] against Figures 3 to 5 In the corresponding second sub-scheme, the closed-pore layer 13 consists of the aforementioned nanoparticles. The porosity of the closed-pore layer 13 can be approximately equal to or less than the porosity of the surface of the glass antireflective layer 12 in contact with the closed-pore layer 13. The closed-pore layer 13 maintains a porosity gradient on the side of the glass antireflective layer 12 away from the glass substrate, further reducing the refractive index and further improving the transmittance of the photovoltaic glass. For example, the porosity or refractive index of the closed-pore layer 13 on the side away from the glass substrate can be equal to the porosity or refractive index of the glass antireflective layer 12 on the side away from the glass substrate.

[0049] against Figures 3 to 5 The corresponding second sub-scheme has a closed-pore layer 13 consisting of the aforementioned nanoparticles. The thickness H2 of the closed-pore layer 13 can be less than the thickness H1 of the glass antireflection layer 12. As a result, the closed-pore layer 13 is thinner and will not affect the high light transmittance of the glass antireflection layer 12 on the side away from the glass substrate.

[0050] against Figures 3 to 5 The corresponding second sub-scheme has a closed-pore layer 13 consisting of the aforementioned nanoparticles. The ratio of the thickness H2 of the closed-pore layer 13 to the thickness H1 of the glass anti-reflection layer 12 can be 1 / 2 to 2 / 3. On the one hand, the thickness of the closed-pore layer 13 is not too thick, so as not to affect the high light transmittance of the glass anti-reflection layer 12 on the side away from the glass substrate. On the other hand, the thickness of the closed-pore layer 13 is not too thin, so as to fully protect the glass anti-reflection layer 12.

[0051] For example, targeting Figures 3 to 5 The corresponding second sub-scheme has a closed-pore layer 13 consisting of the aforementioned nanoparticles. The ratio of the thickness H2 of the closed-pore layer 13 to the thickness H1 of the glass antireflection layer 12 can be 1 / 2, 8 / 15, 17 / 30, 3 / 5, 19 / 30, or 2 / 3.

[0052] For example, regarding Figures 3 to 5 The corresponding second sub-scheme has a closed-pore layer 13 consisting of the aforementioned nanoparticles. The thickness H1 of the glass antireflective layer 12 can be 300 nm to 1000 nm, and the thickness H2 of the closed-pore layer 13 can be 70-170 nm.

[0053] In some embodiments, for Figures 3 to 5 In the corresponding second sub-scheme, the particle size of the nanoparticles can be 45-90nm, and further can be 60-90nm, which can achieve higher transmittance; in the glass antireflection layer 12, the pore size of the pore structure 121 is 2-40nm, and the glass antireflection layer 12 can easily achieve the required gradient change of transmittance.

[0054] For example, targeting Figures 3 to 5The corresponding second sub-scheme allows for nanoparticle sizes of 45nm, 50nm, 55nm, 60nm, 65nm, 70nm, 75nm, 80nm, 85nm, and 90nm. For example, regarding... Figures 3 to 5 The corresponding second sub-scheme has a pore size of 2nm, 5nm, 10nm, 15nm, 20nm, 25nm, 30nm, 35nm, or 40nm in the pore structure 121 of the glass antireflection layer 12.

[0055] against Figures 3 to 5 In the corresponding second sub-scheme, the closed-pore layer 13 consists of the aforementioned nanoparticles, and the pore size of the pore structure in the glass antireflection layer 12 is 2-40 nm. More specifically, the thickness H1 of the glass antireflection layer 12 and the pore size of the pore structure in the glass antireflection layer 12 are within the aforementioned range, and the transmittance of the side of the glass antireflection layer 12 away from the glass substrate 11 is greater, resulting in a higher transmittance of the photovoltaic glass.

[0056] In some embodiments, the closed-pore layer 13 comprises a plurality of nanoparticle schemes, or as described above. Figure 2 The corresponding first sub-scheme, and Figures 3 to 5 The corresponding second sub-scheme includes nanoparticles comprising: hollow nanospheres 1311, and / or, nanoparticles and organic matter attached to at least a portion of the nanoparticles. The hollow nanospheres 1311 in this application may include at least one of: silica hollow nanospheres, titanium dioxide hollow nanospheres, and magnesium fluoride hollow nanospheres, which possess good permeability and are readily available.

[0057] In some embodiments, the nanoparticles in this application may include at least one of: alumina particles, silicon nitride particles, carbon nitride particles, boron carbide particles, silicon carbide particles, and diamond particles; the organic material is selected from: Pluronics F127 (polyoxyethylene-polyoxypropylene copolymer), Pluronics P123 (polyoxypropylene-polyoxyethylene copolymer), CTAB (hexadecyltrimethylammonium bromide), PEG (polyethylene glycol), mPEG (methoxy polyethylene glycol), PS b P2VP (polystyrene) Gathering (2) Vinylpyridine), PS b P4VP (Polystyrene) Gather (4) Vinylpyridine), PS b PMMA (polystyrene) Polymethyl methacrylate (PMMA) and PS b PEO (polystyrene) At least one of (polyethylene oxide). The above-mentioned nanoparticles have good permeability and are readily available.

[0058] It should be noted that the linear molecular formula of Pluronics F127 is HO(CH2CH2O). 106 (CH2CH(CH3)O) 70 (CH2CH2O) 106 The linear molecular formula of H. Pluronics P123 is: HO(CH2CH2O) 20 (CH2CH(CH3)O) 70 (CH2CH2O) 20 H). The nanoparticles can be prepared by: during heat treatment of the film liquid containing nanoparticles, certain substances decompose to form nanopores or pore structures, and the decomposition results in the above-mentioned organic matter, which remains in at least some positions of the nanoparticles.

[0059] against Figure 2 The corresponding first sub-scheme, Figures 3 to 5 The corresponding second sub-scheme includes a closed-pore layer 13 composed of the aforementioned nanoparticles, and a scheme in which the closed-pore layer 13 may include a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass anti-reflection layer. The photovoltaic glass may also include a weather-resistant layer 14 located on the side of the closed-pore layer 13 facing away from the glass substrate 11. The hardness of the weather-resistant layer 14 or the photovoltaic glass is greater than or equal to 4H. A hardness greater than or equal to 4H refers to the Mohs hardness of the weather-resistant layer 14 or the photovoltaic glass. Higher hardness of the weather-resistant layer 14 or the photovoltaic glass can protect the glass anti-reflection layer 12, preventing moisture and other contaminants from entering the photovoltaic glass or photovoltaic module through the pore structure of the glass anti-reflection layer 12, thereby improving the performance and lifespan of the photovoltaic glass or photovoltaic module. For example, the hardness of the weather-resistant layer 14 or the photovoltaic glass can be 4H, 5H, 6H, 7H, 8H, etc.

[0060] It should be noted that photovoltaic glass comprises two surfaces facing each other along their thickness direction. One of these surfaces is the weather-resistant layer. The hardness of photovoltaic glass referred to here primarily refers to the surface of the weather-resistant layer. The hardness of this photovoltaic glass can be determined within the photovoltaic glass itself, or within the photovoltaic module. Without disassembling the module, the hardness of the surface of the photovoltaic glass furthest from the encapsulating film is the hardness referred to here.

[0061] In some embodiments, the refractive index of the weathering layer 14 is less than or equal to 1.7. The low refractive index of the weathering layer 14 avoids any adverse effects on the anti-reflective properties of the glass anti-reflective layer, thus maintaining good transmittance of the photovoltaic glass. Simultaneously, the weathering layer 14 covering the glass anti-reflective layer has high hardness, improving the hardness and weather resistance of the photovoltaic glass. Furthermore, the low refractive index of the weathering layer 14 has a minimal impact on the transmittance of the photovoltaic glass.

[0062] For example, the refractive index of weathering layer 14 can be 1.7, 1.65, 1.6, 1.55, 1.5, 1.45, 1.4, or 1.3.

[0063] It should be noted that both the glass substrate and the anti-reflective layer are primarily made of glass, and the specific type of glass is not limited. In photovoltaic modules, the thickness direction of the photovoltaic module is parallel to the thickness direction L of the glass substrate of the photovoltaic glass.

[0064] It should be noted that in this application, the closed-cell layer mainly serves to maintain the high transmittance of the glass anti-reflective layer and improve the weather resistance of the photovoltaic glass. In this application, a surface closed-cell material with high hardness can be used, such as the aforementioned nanoparticles, such as hollow nanospheres or ultra-hard nanoparticles. Alternatively, a surface sealant can be used to repair the surface cracks of the glass anti-reflective layer to form closed pores, followed by further coating with an ultra-thin weather-resistant layer. The weather-resistant layer can be formed by coating, pulling, deposition, or other methods.

[0065] In some embodiments, the photovoltaic glass of this application is used in photovoltaic modules, or in other words, in photovoltaic modules, the surface roughness of the photovoltaic glass near the encapsulating film is less than the surface roughness of the photovoltaic glass away from the encapsulating film. Specifically, in photovoltaic modules, the surface of the photovoltaic glass near the encapsulating film is in contact with the encapsulating film, so no anti-reflective layer or other structures are provided on the surface of the photovoltaic glass near the encapsulating film to obtain a relatively smooth surface. This not only improves the bonding force between the photovoltaic glass and the encapsulating film, but also reduces air bubbles between the photovoltaic glass and the encapsulating film, further improving the bonding effect between the photovoltaic glass and the encapsulating film and avoiding the phenomenon of delamination between the photovoltaic glass and the encapsulating film. Therefore, in this application, the aforementioned back etching involves etching away the anti-reflective layer on the second side of the glass substrate when anti-reflective layers are formed on both the first and second sides of the glass substrate. During this etching process, the surface of the second side of the glass substrate can be appropriately polished to reduce the surface roughness of the photovoltaic glass near the encapsulating film.

[0066] It should be noted that the surface roughness of the photovoltaic glass near the encapsulating film can be the arithmetic mean deviation Ra of the profile of the surface of the photovoltaic glass near the encapsulating film, the maximum profile height Rz, etc. The roughness can be measured or determined by referring to relevant technical methods, and the specific method is not limited. The method for determining the roughness of the surface of the photovoltaic glass away from the encapsulating film is the same or similar, and will not be elaborated upon to avoid further explanation.

[0067] In some embodiments, the refractive index of the weathering layer 14 is less than or equal to 1.7, and the thickness of the weathering layer is less than or equal to 50 nm. Here, the weathering layer 14 covers the surface of the closed-cell layer 13 and is mainly used to increase the weather resistance of the photovoltaic glass. The refractive index of the weathering layer 14 is not too high, and the thickness is not too thick, so as not to affect the good transmittance of the glass anti-reflection layer 12.

[0068] For example, the thickness of the weather-resistant layer can be 50nm, 40nm, 30nm, 28nm, 25nm, 22nm, 20nm, 15nm, or 10nm.

[0069] Furthermore, the thickness of the weather-resistant layer can be 20-30nm. The relatively thin thickness of the weather-resistant layer will not significantly affect the good transmittance of the glass anti-reflective layer. Moreover, the thickness of the weather-resistant layer is not too thin, which can fully protect the glass anti-reflective layer and provide good weather resistance, thus giving the photovoltaic glass a long lifespan.

[0070] In some embodiments, the weather-resistant layer includes at least one of a silicon dioxide layer, an aluminum-doped silicon dioxide nanolayer, an aluminum oxide layer, and a zirconium oxide layer. These materials have high hardness and low refractive index, or high transmittance, and do not affect the good transmittance performance of the glass antireflective layer. The aging performance, constant humidity and heat performance, and PCT accelerated aging performance (high-pressure boiling aging performance) of the photovoltaic glass of this application were tested in a laboratory simulated environment according to photovoltaic glass testing standards. With and without the weather-resistant layer, the transmittance change of the photovoltaic glass of this application did not exceed 1%.

[0071] Reference Figure 4 As shown, the present application Figure 3 , Figure 5 , Figure 7 and Figure 8 In the photovoltaic glass shown, the porosity of the anti-reflective layer increases along the direction away from the glass substrate. Figure 3 , Figure 5 , Figure 7 and Figure 8 In the photovoltaic glass shown, the refractive index of the anti-reflective layer 12 on the side opposite to the glass substrate 11 is approximately as follows: Figure 4The refractive index curve (which is the lowest or closest to the horizontal axis) is close to 1.05. The refractive index of the glass antireflection layer 12 on the side away from the glass substrate 11 is very small, and the light transmittance of the glass antireflection layer 12 is better.

[0072] Figure 6 In this context, "original film" refers to the glass substrate; "after back etching" means the glass substrate has an anti-reflective coating only on the first side; "after the first film" means the anti-reflective coating has a closed-cell layer; and "after the second film" means... Figure 3 , Figure 5 , Figure 7 and Figure 8 The photovoltaic glass of this application shown is provided with a weather-resistant layer. (Refer to...) Figure 6 Therefore, it can be concluded that the weather-resistant layer has virtually no impact on the good light transmission effect of the glass anti-reflective layer.

[0073] In some embodiments, for Figure 2 In the corresponding first sub-scheme, the closed-pore layer 13 consists of the aforementioned nanoparticles. The porosity of the closed-pore layer 13 is greater than or equal to the porosity of the surface in the glass antireflective layer 12 that is in contact with the closed-pore layer 13. As the porosity of the closed-pore layer containing the nanoparticles increases along the direction away from the glass antireflective layer, it further enhances the gradient of transmittance increase along the direction away from the glass substrate 11 in the glass antireflective layer 12, thereby further improving the transmittance performance of the photovoltaic glass. It should be noted that the increase in porosity of the closed-pore layer containing the nanoparticles along the direction away from the glass antireflective layer can be linear, exponential, or other methods; the specific reduction method is not limited.

[0074] In some embodiments, refer to Figure 7 and Figure 8 The closed-cell layer 13 may include a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure 121 of the glass anti-reflection layer 12, which can serve to stitch together at least a portion of the pore structure 121 of the glass anti-reflection layer 12 and improve the weather resistance of the photovoltaic glass. Figure 9 In this context, single-sided etched glass, whether etched on one side or de-etched on one side, refers to photovoltaic glass without a silicon-crosslinked weather-resistant layer on its anti-reflective coating. Figure 9 The superposition of silane coupling agent and hardening solution refers to Figure 7 and Figure 8 The photovoltaic glass shown contains the aforementioned silicon-crosslinked structure and weather-resistant layer. Figure 9 The horizontal axis represents the wavelength of light, and the vertical axis represents the transmittance of the corresponding photovoltaic glass at that wavelength, in percentage (%). (Refer to...) Figure 9The thickness of the weather-resistant layer is less than or equal to 20 nm. The thickness of the weather-resistant layer is small enough not to affect the good transmittance of the glass anti-reflection layer 12. For example, the thickness of the weather-resistant layer can be 20 nm, 15 nm, 12 nm, 10 nm, 8 nm, 5 nm, 3 nm, 2 nm, 1 nm, or 0.5 nm.

[0075] It should be noted that, referring to Figure 8 In the photovoltaic glass of this application, the thickness H2 of the closed-cell layer 13 with silicon cross-linking structure is relatively small, and the thickness H3 of the weather-resistant layer 13 is also relatively small. Therefore, at a certain magnification, the closed-cell layer 13 containing the silicon cross-linking structure and the weather-resistant layer 14 are not clearly distinguishable, so they are labeled together. Furthermore, since they cannot be accurately distinguished at a certain magnification, therefore... Figure 8 The sum of the thicknesses of the two is marked in the figure. In some embodiments, the silicon-containing crosslinked structure of this application may be a silane coupling agent interface layer deposited on the glass antireflection layer 12. Specifically, the silane coupling agent (e.g., γ-glycidyl etheroxypropyltrimethoxysilane, aminopropyltriethoxysilane, etc.) may be introduced by means of roller coating, spin coating, or dipping. ≡Si-O-Si≡ covalent bonds are formed in at least a portion of the pore structure 121 of the glass antireflection layer 12, repairing microcracks (without sealing microtextures, porosity retention rate > 90%), forming a secondary crosslinked framework layer, enhancing the stability and adhesion of the surface structure, and retaining -NH2 (amino) and / or -CH3 (methyl) functional groups at one end of the silicon-containing crosslinked structure away from the pore structure of the glass antireflection layer to provide anchoring points for the outer weather-resistant layer, further improving the bonding effect between the glass antireflection layer 12 and the weather-resistant layer, and further improving the lifespan of the photovoltaic glass.

[0076] In some embodiments, the photovoltaic glass further includes a light-converting material filling at least one porous structure in the glass anti-reflection layer. Light-converting materials can be classified into upconversion materials and downconversion materials based on the energy conversion direction, with the core difference being the direction of photon energy change and the physical mechanism. Downconversion materials can convert high-energy photons (such as ultraviolet or visible light) into low-energy photons (such as visible or infrared light), thereby improving photoelectric conversion efficiency by broadening the material's absorption range of the solar spectrum. For example, the light-converting material of this application can downconvert short-wavelength photons into the visible light band, enhancing the intensity of the visible light band. This structure not only improves the transmittance of the photovoltaic glass but also helps to increase the doping efficiency of the downconversion material in the glass substrate, further enhancing the light conversion effect. Upconversion materials can convert low-energy photons (such as infrared light) into high-energy photons (such as visible light) through a multi-photon absorption process, similarly improving the transmittance and light utilization efficiency of the photovoltaic glass.

[0077] More specifically, the light transfer material filling at least one pore structure in the glass anti-reflection layer does not affect the good transmittance of the glass anti-reflection layer. The light transfer material can improve the light utilization efficiency of the photovoltaic module in which the photovoltaic glass is located. Figure 10 The image shows the intensity curves of the excitation spectrum of photovoltaic glass containing light-converting materials within 400 nm. It can be concluded that the light-converting materials in this photovoltaic glass reach their excitation peak at approximately 315 nm. Figure 11 The image shows the emission spectrum of the photovoltaic glass containing a light-converting material excited by light at approximately 315 nm. This indicates that the photovoltaic glass converts light at approximately 315 nm into light at approximately 619 nm. The light-converting material can be rare earth metal ions, perovskite quantum dots, etc.

[0078] In some embodiments, at least one pore structure between adjacent nanoparticles in any of the aforementioned photovoltaic glasses is filled with a light-transfer material, and / or at least one pore structure contained within the nanoparticles is filled with a light-transfer material, which can also improve the light utilization efficiency of the photovoltaic module in which the photovoltaic glass is located. For example, the closed-pore layer includes: a plurality of nanoparticles, and at least one pore structure of the glass antireflection layer is filled with a light-transfer material. As another example, for a photovoltaic glass containing a plurality of nanoparticles, a pore structure is formed between adjacent nanoparticles, and / or the nanoparticles contain a pore structure, and at least one pore structure formed between the aforementioned adjacent nanoparticles, and / or at least one pore structure contained within the nanoparticles is filled with a light-transfer material.

[0079] In the case where photovoltaic glass contains nanoparticles and light transfer materials, the light transfer material may only fill at least a portion of the porous structure of the glass antireflection layer, and the nanoparticles may cover the glass antireflection layer; or, the light transfer material may only fill at least a portion of the porous structure formed by adjacent nanoparticles; or, the light transfer material may not only fill at least a portion of the porous structure contained in the nanoparticles; or, the light transfer material may not only fill at least a portion of the porous structure of the glass antireflection layer, but may also fill at least a portion of the porous structure formed between adjacent nanoparticles; or, the light transfer material may also fill at least a portion of the porous structure contained in the nanoparticles. All of these are within the scope of protection of this application.

[0080] In some embodiments, the photovoltaic glass may also contain both nanoparticles and a silicon-containing cross-linked structure. In this case, the nanoparticles cover the silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflection layer, as well as the glass antireflection layer. The photovoltaic glass may also contain both a silicon-containing cross-linked structure and a light-transfer material. In this case, a silicon-containing cross-linked structure may be formed by a silane coupling agent and at least a portion of the pore structure of the glass antireflection layer, and the at least a portion of the pore structure of the glass antireflection layer may be filled with a light-transfer material. The same pore structure may not only be filled with a light-transfer material but may also form a cross-linked silicon-containing cross-linked structure; alternatively, one pore structure may be filled with a light-transfer material, and another pore structure may form a cross-linked silicon-containing cross-linked structure. Photovoltaic glass may also contain a silicon-containing cross-linked structure, a light-transfer material, and nanoparticles. In this case, a silicon-containing cross-linked structure may be formed by a silane coupling agent and at least a portion of the porous structure of the glass anti-reflection layer. The light-transfer material is filled in at least a portion of the porous structure of the glass anti-reflection layer. Nanoparticles cover the silicon-containing cross-linked structure that is cross-linked with at least a portion of the porous structure of the glass anti-reflection layer, as well as the glass anti-reflection layer. The light-transfer material may also be located in at least a portion of the porous structure formed by adjacent nanoparticles.

[0081] It should be noted that in photovoltaic glass, the thickness of the silicon-containing cross-linked structure needs to be less than or equal to 20 nm to avoid affecting the good transmittance of the glass anti-reflection layer.

[0082] In some embodiments, the light-converting material includes rare earth metal ions. Compared to perovskite quantum dots, rare earth metal ions are less prone to decomposition and have better stability, thus providing long-lasting light conversion for photovoltaic glass.

[0083] In some embodiments, rare earth metal ions may include Sm 3+ (Samarium ion), Er 3+ (Erbium ion), Eu 3+ (Europium ion), Y 3+ At least one of (yttrium ions), the light conversion efficiency of the above ions is higher and the stability is better, especially when two or more are combined, the light conversion efficiency is higher.

[0084] In some embodiments, when the photovoltaic glass contains nanoparticles, a porous structure is formed between adjacent hollow nanospheres, and / or the nanoparticles contain a porous structure filled with a light-converting material, which can also improve the light utilization efficiency of the photovoltaic module containing the photovoltaic glass. The specific selection of the light-converting material can be referred to the aforementioned descriptions. For example, the closed-pore layer includes: a photovoltaic glass containing several nanoparticles. Figure 3 , Figure 5The weather-resistant layer shown comprises photovoltaic glass with several nanoparticles, a porous structure formed between adjacent hollow nanospheres, and / or, the nanoparticles contain a porous structure, which is filled with a light-converting material.

[0085] This application also provides a photovoltaic module, including a cell string array, an encapsulating film, and any of the aforementioned photovoltaic glasses. The cell string array includes multiple series-connected and / or parallel cell strings, each cell string comprising an electrical connector and a cell. The electrical connector electrically connects at least two cells. The electrical connector mentioned in this application can be a solder strip, a conductive electrical connector, etc. For example, in a cell string, the electrical connector electrically connects the positive electrode structure of one cell and the negative electrode structure of another adjacent cell. The encapsulating film connects the photovoltaic glass and the cell string array and protects the cell string array. The specific material of the encapsulating film is not limited; for example, it can be EVA (ethylene / vinyl acetate). Any of the aforementioned photovoltaic glasses is located on the side of the encapsulating film away from the cell strings. The second side of the glass substrate of the photovoltaic glass is adjacent to the encapsulating film. In this photovoltaic module, the glass antireflection layer is disposed on the first side of the glass substrate away from the encapsulating film. The refractive index of the glass antireflection layer decreases along the direction away from the glass substrate. The refractive index of the photovoltaic glass is less than that of the encapsulating film. As a result, a gradient of decreasing refractive index is formed from the solar cells inside the photovoltaic module, through the encapsulating film, towards the atmosphere outside the photovoltaic module, thereby reducing optical loss and improving the performance of the photovoltaic module.

[0086] It should be noted that, in determining the refractive index of the antireflective layer at various locations along the direction away from the glass substrate, the same ellipsometer can be used, and the testing can be conducted in the same environment and according to the same testing method. Similarly, in determining the refractive index of the photovoltaic glass and the encapsulating film, the same ellipsometer can be used, and the testing can be conducted in the same environment and according to the same testing method, to reduce testing errors caused by different ellipsometers and other factors.

[0087] In some embodiments, the hardness of the surface of the photovoltaic glass furthest from the encapsulating film is greater than the hardness of the surface of the photovoltaic glass closest to the encapsulating film. Specifically, the surface of the photovoltaic glass furthest from the encapsulating film is the outermost surface of the photovoltaic glass in the photovoltaic module, while the surface of the photovoltaic glass closest to the encapsulating film is the innermost surface of the photovoltaic glass in the photovoltaic module. The outermost surface of the photovoltaic glass in the photovoltaic module has a higher hardness, which can provide better protection for the various components inside the photovoltaic module, further improving the reliability and lifespan of the photovoltaic module.

[0088] It should be noted that the hardness of the photovoltaic glass surface away from the encapsulating film is determined in the same way as the hardness of the photovoltaic glass surface near the encapsulating film, in order to reduce measurement errors.

[0089] In some embodiments, the thickness of the anti-reflective layer is 1% × 10⁻⁶ of the thickness of the photovoltaic glass. -3 Up to 60%×10 -3 Specifically, if the thickness ratio of the anti-reflective layer to the photovoltaic glass is too large, problems may arise regarding the mechanical strength of the photovoltaic glass, and the manufacturing process of using the same glass substrate and the anti-reflective layer on it may be more complex. If the thickness ratio of the anti-reflective layer to the photovoltaic glass is too small, problems may arise regarding the transmittance of the photovoltaic glass. Therefore, in this application, the thickness of the anti-reflective layer, as a percentage of the photovoltaic glass thickness, is within the aforementioned range. This not only results in good mechanical strength and a relatively simple manufacturing process for the photovoltaic glass, but also in high transmittance. For example, the thickness ratio of the anti-reflective layer to the photovoltaic glass thickness can be 1% × 10⁻⁶. -3 1.2%×10 -3 5%×10 -3 10%×10 -3 12%×10 -3 15%×10 -3 19%×10 -3 20%×10 -3 25%×10 -3 30%×10 -3 35%×10 -3 40%×10 -3 45%×10 -3 50%×10 -3 55%×10 -3 60%×10 -3 .

[0090] It should be noted that when the thickness of the antireflective coating varies at different locations, the thickness ratio calculated here can be the minimum thickness, the maximum thickness of the antireflective coating, or the arithmetic mean of the thicknesses at two or more locations. The method for determining the thickness of photovoltaic glass is the same or similar, and will not be repeated here to avoid repetition.

[0091] This application also provides a method for preparing photovoltaic glass, comprising the following steps.

[0092] A glass substrate is provided, comprising a third side and a fourth side opposite to each other along its thickness direction; the third side of the glass substrate is etched to form a glass antireflective layer on the third side; the porosity of the glass antireflective layer increases along a direction away from the glass substrate; a closed-pore layer is deposited on the glass antireflective layer to form a closed-pore layer; the closed-pore layer comprises a plurality of nanoparticles, the particle size of which is larger than the pore size of the pore structure of the surface of the glass antireflective layer in contact with the closed-pore layer; or, the closed-pore layer comprises a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflective layer. The depositing herein may include coating and film deposition, which may refer to existing coating and film deposition methods.

[0093] It should be noted that the photovoltaic glass, the method for preparing photovoltaic glass, and the photovoltaic modules provided in this application can be referred to each other. To avoid duplication, the relevant parts will not be described again.

[0094] It should be noted that the various embodiments of this application can be individual embodiments, or they can be combined separately without logical conflict, and this application does not limit them in this regard.

[0095] The following specific examples further illustrate this application.

[0096] Example 1 The method for preparing the photovoltaic glass in Example 1 includes the following steps (1) to (5).

[0097] (1) Glass pre-cleaning: Place the photovoltaic glass sheet produced by rolling or float glass into an ultrasonic cleaner, add cleaning agent, ultrasonically clean, then ultrasonically rinse with deionized water, and finally put the cleaned glass into a dryer to dry for later use.

[0098] (2) Glass etching: Prepare an etching solution, such as sodium citrate solution, in a reaction vessel. Place the cleaned glass substrate into the reaction vessel and seal it. Then, start heating for etching, followed by cooling to room temperature and removing the sample. Finally, ultrasonically rinse with deionized water and dry to obtain a double-sided etched glass sample, thus obtaining a structure in which both the first and second sides of the glass substrate have anti-reflective layers.

[0099] (3) Removal of the glass antireflection layer on the second side of the glass substrate: In photovoltaic modules, the second side surface of the glass substrate needs to contact the encapsulating film, so it is necessary to remove the glass antireflection layer on the second side of the glass substrate. An etchant such as HF is used to contact the glass antireflection layer on the second side of the glass substrate obtained in step (2) with the etchant. Finally, deionized water is used to rinse and dry the etched glass sample, resulting in a single-sided etched glass sample. The glass antireflection layer on the first side of the glass substrate is formed. Along the direction away from the glass substrate, the transmittance gradually increases or the refractive index gradually decreases. An ellipsometer can be used for measurement and fitting, such as... Figure 2 As shown, the obtained refractive index gradient gradually changes from 1.53 to about 1.38.

[0100] (4) Anti-reflection and hardening by etching and coating: SiO2 hollow nanosphere film liquid is used. The particle size of SiO2 hollow nanospheres is 10-30nm. This forms the closed-pore layer corresponding to the first sub-scheme. The porosity of the closed-pore layer is greater than that of the surface in contact with the closed-pore layer in the glass anti-reflection layer. The refractive index of the closed-pore layer is about 1.29. It further forms a layer with gradually increasing transmittance or gradually decreasing refractive index gradient along the direction away from the glass substrate with the above-mentioned etched layer. The coating equipment includes roller coating, spin coating, dip coating, and scraping coating equipment. After coating, curing is completed in the drying equipment.

[0101] (5) Glass tempering: The glass that has completed the above steps is placed in a tempering equipment for tempering. After tempering, the glass is taken out after the temperature drops to room temperature to obtain high-transparency and high-reliability photovoltaic glass.

[0102] In the photovoltaic glass of Example 1, the thickness of the glass anti-reflection layer 12 is about 100 nm, and the thickness H2 of the closed-pore layer 13 is about 110 nm.

[0103] A. Transmittance performance characterization: The average transmittance of the photovoltaic glass in 500 Example 1 samples was approximately 95.04%.

[0104] B. Hardness and weather resistance: After double-sided etching (2), the hardness of the two surfaces is >3H. After removing the glass anti-reflection layer on the second side of the glass substrate (3), the hardness of the surface on the second side of the glass substrate is >6H. After coating the etched surface (4), the hardness of the surface of the photovoltaic glass away from the second side is >3H. The aging performance, constant humidity and heat and PCT accelerated aging performance of the complete sample were tested in a laboratory simulation environment according to the photovoltaic glass test standard. The transmittance change did not exceed 1%. Example 2 The photovoltaic glass in Example 2 is based on the structure of Example 1, with at least a portion of the pore structure of the glass antireflection layer filled with a light-transfer material; the thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 2, the closed-pore layer 13 covers the side of the glass antireflection layer containing the light-transfer material that is away from the glass substrate. The light-transfer material can be formed by methods such as light-transfer material coating (after the pore structure is formed, the light-transfer precursor solution is directly coated on the surface of the glass antireflection layer away from the glass substrate), vacuum adsorption (after the pore structure is formed, the photovoltaic glass semi-finished product is immersed in a rare earth doping solution and penetrates into the etched pore structure by vacuuming), or hydrothermal reaction (mixing with the etching solution to simultaneously perform etching and doping). After the liquid containing the light-transfer material has completely penetrated into the pore structure, the glass sample is removed, and the glass surface is cleaned and dried.

[0105] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 2 are roughly the same as those in Example 1. However, due to the addition of light conversion materials, the photovoltaic module containing the photovoltaic glass in Example 2 has a higher light conversion efficiency.

[0106] Example 3 The photovoltaic glass in Example 3 is based on the photovoltaic glass in Example 2. A porous structure is formed between adjacent hollow nanospheres of the closed-pore layer 13, and this porous structure is filled with a light-transfer material. Alternatively, the hollow nanospheres may contain porous structures filled with light-transfer material. The thickness of the light-transfer material is very small, less than or equal to 5 nm. That is, in the photovoltaic glass of Example 3, at least a portion of the porous structure of the glass antireflective layer is also filled with light-transfer material. Simultaneously, the porous structures formed between adjacent hollow nanospheres of the closed-pore layer 13, and / or the porous structures contained within the hollow nanospheres, are filled with light-transfer material. In the photovoltaic glass of Example 3, the closed-pore layer 13 containing the light-transfer material covers the side of the glass antireflective layer containing the light-transfer material that faces away from the glass substrate. The arrangement of the light-transfer material is not limited.

[0107] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 3 are roughly the same as those in Example 2. However, due to the addition of more light-converting materials, the photovoltaic module containing the photovoltaic glass in Example 3 has a higher light conversion efficiency.

[0108] Example 4 The photovoltaic glass in Example 4 is based on the photovoltaic glass in Example 1. A porous structure is formed between adjacent hollow nanospheres of the closed-pore layer 13, and / or the hollow nanospheres contain a porous structure filled with a light-transfer material. The thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 4, the closed-pore layer 13 containing the light-transfer material covers the side of the glass antireflection layer facing away from the glass substrate. The arrangement of the light-transfer material is not limited.

[0109] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 4 are roughly the same as those in Example 1. However, due to the addition of light conversion materials, the photovoltaic module containing the photovoltaic glass in Example 4 has a higher light conversion efficiency.

[0110] Example 5 The photovoltaic glass in Example 5 differs from the photovoltaic glass in Example 1 in that it has a closed-cell layer 13. The structure of the photovoltaic glass in Example 5 is shown in the figure. Figure 3 and Figure 5 The main difference between the photovoltaic glass preparation method of Example 5 and that of Example 1 lies in step (2), and step (4) of Example 5 is also slightly different from step (4) of Example 1. The following only introduces the differences between step (2) and step (4) of Example 5 and that of Example 1. Compared with step (2) of Example 1, the concentration of sodium citrate solution in step (2) of Example 5 is slightly higher, and the etching time is slightly longer. The rest is the same as step (2) of Example 1. Therefore, the gradient of the increase in transmittance of the glass antireflection layer in Example 5 is larger. The refractive index gradient of the glass antireflection layer in Example 5 gradually changes from 1.53 to 1.07, and the thickness of the glass antireflection layer is about 300 nm. In step (4) of Example 5, the thickness H2 of the closed-pore layer containing the nano-hollow spheres is about 120 nm, the particle size of the nano-hollow spheres is 60-90 nm, the porosity of the nano-hollow spheres in Example 5 is approximately equal to the porosity of the surface in the glass antireflection layer that is in contact with the closed-pore layer, the refractive index of the closed-pore layer is about 1.1, and it is approximately equal to the refractive index of the side of the glass antireflection layer away from the glass substrate, which is 1.07. After setting the nano-hollow spheres, a hard coating liquid is also rolled onto the nano-hollow spheres. The refractive index of the weather-resistant layer formed by the hard coating liquid is 1.46. After the roll coating, it is cured in a drying equipment. The thickness H3 of the weather-resistant layer is about 30 nm. Through the A. transmittance performance characterization test similar to that of Example 1, it is found that the average transmittance of the photovoltaic glass in Example 5 reaches 94.83%. Through the B. hardness and weather resistance test similar to that of Example 1, it is found that the hardness of the surface of the photovoltaic glass, that is, the outer surface of the weather-resistant layer, is greater than or equal to 4H. The aging performance, constant humidity and heat, and PCT accelerated aging performance of complete samples were tested in a laboratory simulated environment according to photovoltaic glass testing standards, and the transmittance change did not exceed 1%.

[0111] Example 6 The photovoltaic glass in Example 6, based on the photovoltaic glass in Example 5, further includes a light-transfer material filled in at least a portion of the porous structure of the glass anti-reflection layer; the thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 6, the closed-cell layer 13 covers the side of the glass anti-reflection layer containing the light-transfer material that faces away from the glass substrate.

[0112] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 6 are roughly the same as those in Example 5. However, due to the addition of light conversion materials, the photovoltaic module containing the photovoltaic glass in Example 6 has a higher light conversion efficiency.

[0113] Example 7 The photovoltaic glass in Example 7 is based on the photovoltaic glass in Example 6, wherein a porous structure is formed between adjacent hollow nanospheres of the closed-cell layer, and / or, the hollow nanospheres contain a porous structure filled with a light-transfer material; the thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 7, the closed-cell layer containing the light-transfer material covers the side of the glass antireflective layer containing the light-transfer material that faces away from the glass substrate.

[0114] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 7 are roughly the same as those in Example 6. However, due to the addition of more light-converting materials, the photovoltaic module containing the photovoltaic glass in Example 7 has a higher light conversion efficiency.

[0115] Example 8 The photovoltaic glass in Example 8 is based on the photovoltaic glass in Example 5, wherein a porous structure is formed between adjacent hollow nanospheres of the closed-cell layer, and / or the hollow nanospheres contain a porous structure filled with a light-transfer material; the thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 8, the closed-cell layer containing the light-transfer material covers the side of the glass antireflective layer facing away from the glass substrate.

[0116] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 8 are roughly the same as those in Example 5. However, due to the addition of light conversion materials, the photovoltaic module containing the photovoltaic glass in Example 8 has a higher light conversion efficiency.

[0117] Example 9 The photovoltaic glass in Example 9 differs from that in Example 5 in that it has a closed-cell layer. The fabrication method of the photovoltaic glass in Example 9 does not include a step in preparing nanoparticles. In Example 9, a silane coupling agent interface layer is deposited on an etched glass antireflection layer. A silane coupling agent (e.g., γ-glycidyl etheroxypropyltrimethoxysilane, aminopropyltriethoxysilane, etc.) is introduced using methods such as roller coating, spin coating, or dipping. This forms ≡Si-O-Si≡ covalent bonds in the pore structure of the glass antireflection layer, repairing microcracks (without sealing microtextures, porosity retention > 90%), forming a silicon-containing cross-linked structure, and enhancing the surface structure. The stability and bonding of the structure are improved, and the -NH2 / -CH3 functional groups at the ends of the silicon-containing cross-linked structure are retained to provide anchoring points for the weather-resistant layer. Finally, a weather-resistant layer is deposited on the surface, and a high-hardness functional nano-weather-resistant layer is coated by roller coating, spin coating, or dip coating, such as a dense silica sol-gel coating, an aluminum-doped SiO2 nano-coating, an alumina / zirconia sol coating, or an organic-inorganic hybrid coating, to further improve the surface hardness, wear resistance, and environmental corrosion resistance. Example 5. In Example 9, the thickness of the silicon-containing cross-linked structure is very small, less than or equal to 5 nm, and the total thickness of the weather-resistant layer and the silicon-containing cross-linked structure is about 30 nm.

[0118] Example 10 The photovoltaic glass of Example 10, based on the photovoltaic glass of Example 9, further includes a light-transfer material filled in at least a portion of the porous structure of the glass anti-reflection layer; the thickness of the light-transfer material is very small, less than or equal to 5 nm. In the photovoltaic glass of Example 10, a closed-cell layer 13 covers the side of the glass anti-reflection layer containing the light-transfer material that faces away from the glass substrate.

[0119] The transmittance, hardness, and weather resistance of the photovoltaic glass in Example 10 are roughly the same as those in Example 9. However, due to the addition of light conversion materials, the photovoltaic module containing the photovoltaic glass in Example 10 has a higher light conversion efficiency.

[0120] Comparative Example 1 Photovoltaic glass substrates produced by rolling or float glass processes are placed in an ultrasonic cleaner, a cleaning agent is added, and ultrasonic cleaning is performed. Then, the substrates are ultrasonically rinsed with deionized water. Finally, the rinsed glass is placed in a dryer to dry. The glass in Comparative Example 1 is simply the glass substrate from Examples 1 to 20 above, and only the aforementioned step (1) glass pre-cleaning was performed.

[0121] Through a transmittance performance characterization test similar to that of Example 1, the transmittance curves of Example 1 and Comparative Example 1 of this application are compared with those of Comparative Example 1. Figure 12 It can be concluded that the transmittance of existing photovoltaic glass is significantly low, which will lead to optical loss.

[0122] Comparative Example 2 The only difference between Comparative Example 2 and Example 5 is that Comparative Example 2 did not prepare a closed-pore layer containing hollow nanospheres; instead, a weather-resistant layer was directly formed on the side of the glass antireflective layer facing away from the glass substrate. The remaining steps of Comparative Example 2 are the same as in Example 5. That is, Comparative Example 2 directly places the weather-resistant layer on the glass antireflective layer. The transmittance performance was characterized using a method similar to that of Example 1, referring to… Figure 13 Because Comparative Example 2 does not contain the barrier effect of the closed-pore layer with nano-hollow spheres, the particles of the weather-resistant layer in Comparative Example 2 are small and can penetrate into the pore structure of the glass anti-reflection layer. The weather-resistant layer in Comparative Example 2 will reduce the transmittance of the photovoltaic glass, especially the transmittance of visible light, which will cause optical loss.

[0123] It should be noted that the photovoltaic glass provided in this application is not limited to the photovoltaic industry, but can also be used in building materials glass, automobile windows and other related glass industries that require high light transmittance, good hardness and good weather resistance.

[0124] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0125] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A photovoltaic glass, characterized in that, include: A glass substrate, along the direction of its thickness, includes opposing first and second sides; An anti-reflective layer is located on the first side of the glass substrate; The porosity of the glass antireflective layer increases along the direction away from the glass substrate; A closed-pore layer comprising a plurality of nanoparticles covering the side of the glass antireflective layer away from the glass substrate, wherein the particle size of the nanoparticles is larger than the pore size of the pore structure of the surface of the glass antireflective layer in contact with the closed-pore layer; or, the closed-pore layer comprising a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflective layer.

2. The photovoltaic glass according to claim 1, characterized in that, Along the direction away from the glass substrate, the pore size of the antireflective layer increases, and the antireflective layer is integrally formed with the glass substrate.

3. The photovoltaic glass according to claim 1, characterized in that, The closed-pore layer is composed of the aforementioned nanoparticles, and the porosity of the closed-pore layer is greater than or equal to the porosity of the surface in the glass antireflective layer that is in contact with the closed-pore layer.

4. The photovoltaic glass according to claim 3, characterized in that, The first surface of the photovoltaic glass is one surface of the closed-cell layer, and the hardness of the first surface of the photovoltaic glass is greater than or equal to 3H.

5. The photovoltaic glass according to claim 1, characterized in that, The thickness of the closed-cell layer is less than the thickness of the glass antireflective layer.

6. The photovoltaic glass according to claim 5, characterized in that, The ratio of the thickness of the closed-cell layer to the thickness of the glass antireflective layer is greater than or equal to 1 / 2 and less than or equal to 2 / 3.

7. The photovoltaic glass according to claim 1, characterized in that, The nanoparticles include: hollow nanospheres, and / or, nanoparticles and organic matter attached to at least a portion of the nanoparticles; The hollow nanospheres include at least one of the following: silicon dioxide hollow nanospheres, titanium dioxide hollow nanospheres, and magnesium fluoride hollow nanospheres; The nanoparticles include at least one of the following: alumina particles, silicon nitride particles, carbon nitride particles, boron carbide particles, silicon carbide particles, and diamond particles; the organic material is selected from: polyoxyethylene-polyoxypropylene copolymer, polyoxypropylene-polyoxyethylene copolymer, hexadecyltrimethylammonium bromide, polyethylene glycol, methoxy polyethylene glycol, and polystyrene. Gathering (2) Vinylpyridine, polystyrene Gather (4) Vinylpyridine, polystyrene Polymethyl methacrylate and polystyrene At least one of the following: polyethylene oxide.

8. The photovoltaic glass according to claim 5, characterized in that, The porosity of the closed-cell layer is less than or equal to the porosity of the surface in the glass antireflective layer that is in contact with the closed-cell layer.

9. The photovoltaic glass according to claim 1, characterized in that, Also includes: A weather-resistant layer is located on the side of the closed-cell layer opposite to the glass substrate. The hardness of the photovoltaic glass is greater than or equal to 4H, and the thickness of the weather-resistant layer is less than or equal to 50nm.

10. The photovoltaic glass according to claim 9, characterized in that, The weather-resistant layer includes at least one of a silicon dioxide layer, an aluminum-doped silicon dioxide nanolayer, an aluminum oxide layer, and a zirconium oxide layer.

11. The photovoltaic glass according to any one of claims 1 to 10, characterized in that, The end of the silicon-containing crosslinked structure away from the porous structure of the glass antireflective layer contains amino functional groups and / or methyl functional groups.

12. The photovoltaic glass according to any one of claims 1 to 10, characterized in that, Also includes: Optical transfer materials; The light-converting material fills at least one pore structure in the glass antireflective layer; And / or, The phototransfer material fills the spaces between adjacent nanoparticles to form a porous structure; and / or, the nanoparticles contain a porous structure, and the phototransfer material fills the porous structure of the nanoparticles.

13. The photovoltaic glass according to claim 12, characterized in that, The optical transfer material includes: Sm 3+ Er 3+ Eu 3+ Y 3+ At least one of them.

14. A photovoltaic module, characterized in that, include: Battery string array; the battery string includes several battery cells; An encapsulating film is located on at least one side of the battery string array; The photovoltaic glass according to any one of claims 1 to 13, wherein the photovoltaic glass is located on the side of the encapsulating film away from the battery string array, the glass antireflection layer is disposed on the first side of the glass substrate away from the encapsulating film, the refractive index of the glass antireflection layer decreases along the direction away from the glass substrate, and the refractive index of the photovoltaic glass is less than the refractive index of the encapsulating film.

15. The photovoltaic module according to claim 14, characterized in that, The hardness of the surface of the photovoltaic glass away from the encapsulating film is greater than the hardness of the surface of the photovoltaic glass close to the encapsulating film.

16. The photovoltaic module according to claim 14, characterized in that, The surface roughness of the photovoltaic glass near the encapsulating film is less than the surface roughness of the photovoltaic glass away from the encapsulating film.

17. The photovoltaic module according to claim 14, characterized in that, The thickness of the anti-reflective layer is 1% × 10⁻⁶ of the thickness of the photovoltaic glass. -3 Up to 60%×10 -3 .

18. A method for preparing photovoltaic glass, characterized in that, include: A glass substrate is provided, including opposing third and fourth sides along the direction of its thickness; The third side of the glass substrate is etched to form a glass antireflection layer on the third side; the porosity of the glass antireflection layer increases in the direction away from the glass substrate. A closed-cell layer is deposited on the glass antireflective layer; the closed-cell layer includes a plurality of nanoparticles, the particle size of which is larger than the pore size of the pore structure of the surface of the glass antireflective layer in contact with the closed-cell layer; or, the closed-cell layer includes a silicon-containing cross-linked structure that forms a cross-link with at least a portion of the pore structure of the glass antireflective layer.

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