Solar cell front protective film, preparation method thereof and back contact cell

Abstract

The invention provides a solar cell front protective film, a preparation method thereof and a back contact cell. The solar cell front surface protection film comprises a first cell protection film and a second cell protection film which are stacked in sequence. The first battery protection film is in direct contact with the light receiving surface of the solar battery body; the first battery protection film is prepared on the basis of a polyacrylate adhesive; and the second battery protection film is made based on an organic silicon adhesive. The solar cell front surface protection film has the advantages of low fluidity, high light transmission, scratch resistance, strong adhesion with the surface of the cell, effective protection of the front surface of the cell, good adhesion with a front surface packaging adhesive film, direct lamination with the front surface packaging adhesive film, no need of tearing after use, no reduction of production efficiency, ultraviolet resistance, damp and heat resistance and the like, and is suitable for large-scale production. And through material selection and structural design, the light trapping effect of the solar cell can be improved, and the conversion efficiency of the solar cell and the power of the assembly can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of solar cells, and in particular to a front protective film for solar cells and a preparation method thereof, a photoelectric device, a back contact cell, a photovoltaic module, and a photovoltaic system. Background Art

[0002] Back-contact battery is a new type of battery technology that can improve the efficiency of batteries and modules. Its main feature is that the positive and negative electrodes of the battery cell are all located on the back of the battery cell, distributed in a finger-like shape, in order to greatly improve the efficiency of the battery and module. A passivation film is provided on the front of the battery cell, but there is no grid line blocking the front of the battery cell. Since the positive and negative metal electrodes are distributed on the back of the battery cell and there is no metal electrode on the front of the battery cell, after the battery cell is manufactured, during the assembly process and other movement processes, the passivation film on the front of the battery cell will directly contact the production line, causing the front passivation film to easily rub against other objects and be scratched, affecting the absorption of light, and thus affecting the power generation efficiency of the battery. It can be seen that after the battery cell of the back-contact battery is manufactured, its front side has always been at a high risk of being scratched, which has an adverse effect on the subsequent assembly process and the power generation efficiency of the battery.

[0003] At present, in order to reduce the risk of scratches on the front of the battery cells, isolation paper is usually placed between the battery cells to protect the individual battery cells from being scratched during the production process. This method has the following defects: (1) A paper dispensing machine is required in both the battery production stage and the component production stage. The function of the paper dispensing machine is to place isolation paper between the battery cells, with one piece placed on each battery cell. A large amount of isolation paper is consumed during the production process. The isolation paper needs to be replaced after long-term use or multiple uses, which will further increase material costs and reduce production efficiency; (2) The battery cells need to be tested during the production process. At this time, the isolation paper must be removed, otherwise it will affect the detection of the battery cells, which further reduces production efficiency; (3) The isolation paper can only protect a single battery cell from being scratched during the production process. After the battery cells are manufactured, the isolation paper can no longer protect the battery cells during storage, movement, and component production.

[0004] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the invention

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide a solar cell front protective film and a preparation method thereof, and a back contact cell. The solar cell front protective film includes a first cell protective film and a second cell protective film stacked in sequence, and has the advantages of low fluidity, high light transmittance, scratch resistance, strong adhesion to the cell surface, effective protection of the cell front, good adhesion to the front packaging film, direct stacking with the front packaging film, no need to tear off after use, no reduction in production efficiency, UV resistance, moisture and heat resistance, etc., and through material selection and structural design, it can increase the light trapping effect of solar cells, improve the conversion efficiency of solar cells and the power of components.

[0006] To achieve the above objectives, this application adopts the following technical solutions: A solar cell front protection film comprises a first cell protection film and a second cell protection film stacked in sequence; the first cell protection film is in direct contact with a light-receiving surface of a solar cell body; The first battery protection film is made of polyacrylate adhesive; The second battery protection film is made based on organic silicone adhesive.

[0007] In some embodiments, the sum of the thicknesses of the first battery protection film and the second battery protection film is 10 μm to 100 μm; The thickness ratio of the first battery protection film to the second battery protection film is 1:1.8~1:2.2.

[0008] In some embodiments, the polyacrylate adhesive comprises, by weight: 80-100 parts of acrylic soft monomer, 5-10 parts of hard monomer, 0.1-0.5 parts of initiator, 1-10 parts of functional monomer, and 20-50 parts of solvent; wherein the functional monomer comprises one or more of silane monomer, hydroxyl-containing monomer, carboxylic acid monomer, and epoxy monomer; and / or The organic silicone adhesive comprises, by weight: 80-100 parts of terminal hydroxyl polydimethylsiloxane, 1-5 parts of a cross-linking agent, 0.2-0.5 parts of a catalyst, 10-20 parts of an inorganic filler, 1-5 parts of a coupling agent, 20-50 parts of a solvent, and 1-5 parts of a dispersant.

[0009] In some embodiments, the acrylic soft monomer includes one or more of ethyl acrylate, butyl acrylate, and isooctyl acrylate; and / or The hard monomer includes one or more of methyl methacrylate, styrene, acrylonitrile, and glycidyl methacrylate.

[0010] In some embodiments, the silane monomer includes one or more of γ-methacryloxypropyltrimethoxysilane and vinyltriethoxysilane; The hydroxyl-containing monomer includes one or more of hydroxyethyl acrylate and hydroxypropyl acrylate; The carboxylic acid monomer includes one or more of acrylic acid and methacrylic acid; The epoxy monomer includes glycidyl methacrylate.

[0011] In some embodiments, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and tert-butyl peroxyhexahydroterephthalate.

[0012] In some embodiments, the crosslinking agent includes one or more of an alkoxysilane crosslinking agent, an acyloxysilane crosslinking agent, and an aminosilane crosslinking agent; and / or The coupling agent includes one or more of a silane coupling agent and a titanate coupling agent.

[0013] In some embodiments, the catalyst includes one or more of an organic tin compound, a phthalate catalyst, and an amine catalyst.

[0014] In some embodiments, the inorganic filler includes fumed silica, and the particle size of the fumed silica ranges from 7 to 40 nm.

[0015] In some embodiments, the dispersant includes one or more of an ionic surfactant, a nonionic surfactant, a hyperdispersant, and a low molecular weight polymer; Wherein, the ionic surfactant includes one or more of anionic surfactant and hexadecyltrimethylammonium bromide; the anionic surfactant includes one or more of sodium dodecylbenzene sulfonate and sodium dodecyl sulfate.

[0016] In some embodiments, the solvent includes one or more of toluene, xylene, acetone, and ethyl acetate.

[0017] The present application also provides a method for preparing a solar cell front protective film, comprising: The viscosity of the polyacrylate adhesive is adjusted to 2000-3000 mPa.s to obtain the polyacrylate adhesive A1; the polyacrylate adhesive A1 is applied to the light-receiving surface of the solar cell body to form a polyacrylate adhesive layer to obtain a first target cell sheet; The viscosity of the organic silicone adhesive is adjusted to 3500-5000 mPa.s to obtain the organic silicone adhesive B1; the organic silicone adhesive B1 is coated on the polyacrylate adhesive layer to form an organic silicone adhesive layer to obtain a second target battery cell; The second target cell is thermally cured to form the solar cell front protection film.

[0018] The present application also provides a back contact battery, comprising: The solar cell front protection film as described above; or The solar cell front protection film is prepared by the above-mentioned preparation method.

[0019] The present application also provides a photovoltaic module, including: At least one battery string, the battery string comprising at least two back-contact batteries as described above.

[0020] The present application also provides a photovoltaic system, comprising the photovoltaic assembly as described above.

[0021] In the technical solution of the present application, the front protective film of the solar cell includes a first battery protective film and a second battery protective film stacked in sequence, which have the functions of low fluidity, high light transmittance, scratch resistance, strong adhesion to the battery surface, effective protection of the battery front, good adhesion to the front packaging film, can be directly stacked with the front packaging film, does not need to be torn off after use, will not reduce production efficiency, UV resistance, moisture and heat resistance, etc., and through material selection and structural design, it can increase the light trapping effect of solar cells, improve the conversion efficiency of solar cells and the power of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the multiple drawings represent the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings only depict some embodiments disclosed in the present application and should not be regarded as limiting the scope of the present application. Figure 1 Schematic diagram of the structure of an N-type back contact battery in an embodiment of the present application.

[0023] Figure 2 Schematic diagram of the structure of an N-type photovoltaic module in an embodiment of the present application.

[0024] Numbers in the figure: 11, N-type back contact battery body; 12, first battery protection film; 13, second battery protection film; 1, N-type back contact battery; 2, front packaging film EPE; 3, ultra-white fully tempered single-coated glass; 4, white high-reflective EVA packaging film; 5, KPC polymer photovoltaic backplane. DETAILED DESCRIPTION

[0025] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings. In the accompanying drawings, for clarity, the sizes of layers, regions, elements and their relative sizes may be exaggerated. Wherein the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present application, and cannot be understood as limitations on the present application. It should be noted that, in the absence of conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0026] It should be understood that when an element or layer is referred to as "on ...", "adjacent to ...", "connected to" or "coupled to" other elements or layers, it can be directly on, adjacent to, connected to or coupled to other elements or layers, or there can be intervening elements or layers. On the contrary, when an element is referred to as "directly on ...", "directly adjacent to ...", "directly connected to" or "directly coupled to" other elements or layers, there is no intervening element or layer. It should be understood that although the terms first, second, third, etc. can be used to describe various elements, components, regions, layers and / or parts, these elements, components, regions, layers and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer or part from another element, component, region, layer or part. Therefore, without departing from the teachings of the present disclosure, the first element, component, region, layer or part discussed below can be represented as the second element, component, region, layer or part. And when the second element, component, region, layer or part is discussed, it does not mean that the present disclosure necessarily has the first element, component, region, layer or part.

[0027] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0028] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way can be interchangeable where appropriate, so that the embodiments of the present application described herein can be implemented in an order other than those illustrated or described herein, for example. In addition, the terms "including" and "having" and any of their variations are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0029] In the present application, when it comes to a numerical interval (i.e., a numerical range), unless otherwise specified, the distribution of the optional numerical values ​​in the numerical interval is considered to be continuous, and includes the two numerical endpoints (i.e., the minimum and maximum values) of the numerical interval, and each numerical value between the two numerical endpoints. Unless otherwise specified, when the numerical interval only refers to an integer in the numerical interval, it includes the two endpoint integers of the numerical range, and each integer between the two endpoints, which is equivalent to directly listing each integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical range disclosed in the present application should be understood to include any and all sub-ranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, a percentage, a ratio, etc. "Numerical interval" allows for broadly including quantitative intervals such as percentage intervals, ratio intervals, and ratio intervals.

[0030] The present application aims to provide a solar cell front protective film and a preparation method thereof, and a back contact cell. The solar cell front protective film comprises a first cell protective film and a second cell protective film stacked in sequence, and has the advantages of low fluidity, high light transmittance, scratch resistance, strong adhesion to the cell surface, effective protection of the cell front, good adhesion to the front packaging film, direct stacking with the front packaging film, no need to tear off after use, no reduction in production efficiency, UV resistance, moisture and heat resistance, etc., and through material selection and structural design, it can increase the light trapping effect of solar cells, improve the conversion efficiency of solar cells and the power of components.

[0031] The embodiment of the present application provides a solar cell front protection film, comprising a first cell protection film and a second cell protection film stacked in sequence; the first cell protection film is in direct contact with the light-receiving surface of the solar cell body; The first battery protection film is made of polyacrylate adhesive; The second battery protection film is made based on organic silicone adhesive.

[0032] In an embodiment of the present application, the thickness of the first battery protection film may be 1nm~1000μm (for example, 1nm, 100nm, 300nm, 500nm, 700nm, 900nm, 10μm, 100μm, 200μm, 500μm, 800μm, 1000μm); the thickness of the second battery protection film may be 1nm~1000μm (for example, 1nm, 100nm, 300nm, 500nm, 700nm, 900nm, 10μm, 100μm, 200μm, 500μm, 800μm, 1000μm); the thickness of the first battery protection film and the second battery protection film may be set according to actual needs.

[0033] In the embodiment of the present application, the front protective film of the solar cell has a strong adhesion to the surface of the cell. The front protective film of the solar cell can be directly attached to the surface of the cell to effectively protect the surface of the cell and reduce the risk of scratches on the front of the cell. Compared with the traditional method of protecting the front of the cell by placing isolation paper between the cells, it has the following advantages: 1. No paper dispenser is required, and no large amount of isolation paper is consumed; 2. The front protective film of the solar cell is always adsorbed and attached to the surface of the cell. After the cell is manufactured, the storage, movement and assembly production can also effectively protect the surface of the cell and reduce the risk of scratches on the front of the cell. Specifically, in the embodiment of the present application, a front protective film of the solar cell is provided on the cell. During the transfer and processing of the cell, the back welding strip of the cell or other factors can be prevented from damaging the front passivation structure of the cell, resulting in a decrease in the efficiency and reliability of the cell, thereby improving the appearance quality of the cell itself, that is, the photovoltaic module after packaging. In the embodiment of the present application, the front protective film of the solar cell does not need to be removed, and the production line can be directly transferred. In the lamination process, the front protective film of the solar cell directly forms a fusion interface with the front adhesive film layer and the front passivation layer of the cell, which does not affect the production efficiency.

[0034] In the embodiment of the present application, the back contact battery front passivation film layer is usually made of SiO2 / SiN x The structure has a refractive index of >1.5, while the refractive index of silicone adhesive is usually 1.40-1.42, and the refractive index of acrylate adhesive is 1.48-1.52. The structural design with the refractive index increasing from small to large can increase the utilization of light by the battery cell.

[0035] In the embodiment of the present application, the front protective film of the solar cell includes a first battery protective film and a second battery protective film stacked in sequence, which have the functions of low fluidity, high light transmittance, scratch resistance, strong adhesion to the battery surface, effective protection of the battery front, good adhesion to the front packaging film, can be directly stacked with the front packaging film, does not need to be torn off after use, will not reduce production efficiency, UV resistance, moisture and heat resistance, etc., and through material selection and structural design, it can increase the light trapping effect of solar cells, improve the conversion efficiency of solar cells and the power of components.

[0036] In an optional embodiment, the sum of the thicknesses of the first battery protection film and the second battery protection film is 10 μm to 100 μm (for example, 10 μm, 20 μm, 30 μm, 40 μm, 50 μm, 60 μm, 70 μm, 80 μm, 90 μm, 100 μm); The thickness ratio of the first battery protection film to the second battery protection film is 1:1.8 to 1:2.2 (for example, 1:1.8, 1:1.9, 1:2, 1:2.1, 1:2.2).

[0037] In the embodiment of the present application, the thickness parameters of the first battery protection film and the second battery protection film are optimized, and the refractive index of the first battery protection film and the second battery protection film are both less than the refractive index of the passivation film on the light-receiving surface of the battery cell, so as to form a light trapping effect on the surface of the battery cell, which is beneficial to improve the absorption rate of the battery cell to light and improve the conversion efficiency of the battery cell. In addition, by designing the thickness of the first battery protection film and the second battery protection film, the propagation path of light in the protective film on the front of the solar cell can be reduced, thereby increasing the absorption or scattering of light; the superposition of the two measures can further improve the conversion efficiency of the battery cell and further improve the output power of the photovoltaic module.

[0038] In an optional embodiment, the polyacrylate adhesive comprises, by weight: 80-100 parts of acrylic soft monomers, 5-10 parts of hard monomers, 0.1-0.5 parts of initiators, 1-10 parts of functional monomers, and 20-50 parts of solvents; wherein the functional monomers include one or more of silane monomers, hydroxyl-containing monomers, carboxylic acid monomers, and epoxy monomers; and / or The organic silicone adhesive comprises, by weight: 80-100 parts of terminal hydroxyl polydimethylsiloxane, 1-5 parts of a cross-linking agent, 0.2-0.5 parts of a catalyst, 10-20 parts of an inorganic filler, 1-5 parts of a coupling agent, 20-50 parts of a solvent, and 1-5 parts of a dispersant.

[0039] In the embodiment of the present application, the silicon dioxide in the passivation layer on the surface of the battery is an inorganic material with a high surface energy, while the acrylic adhesive is an organic material with a relatively low surface energy. This difference in surface energy leads to limited wetting ability of the adhesive on the surface of silicon dioxide; in addition, the surface activity of silicon dioxide is low, the Si-O bond on its surface is relatively stable, and the chemical interaction with the functional groups in the acrylic adhesive is weak, so the bonding force between the interface of silicon dioxide and acrylic adhesive is weak. In the embodiment of the present application, by adding functional monomers such as KH570 (γ-methacryloxypropyltrimethoxysilane) to the acrylic adhesive formula, the siloxane group at one end of the monomer can undergo condensation reaction with active groups such as hydroxyl groups on the surface of silicon dioxide to form a strong chemical bond, and the polymerizable vinyl and acryloyl groups at the other end of the monomer can participate in the polymerization reaction of acrylic esters, thereby establishing a strong connection between the polyacrylate adhesive and the silicon dioxide surface to ensure the long-term reliability of photovoltaic modules.

[0040] In the embodiments of the present application, the composition ratio of the polyacrylate adhesive and / or the silicone adhesive is optimized to control the shrinkage rate and adhesion of the first battery protective film and the second battery protective film, so that effective adhesion can be continuously formed between the protective battery cell, the front protective film of the solar cell and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0041] In an optional embodiment, the acrylic ester soft monomer includes one or more of ethyl acrylate, butyl acrylate, and isooctyl acrylate; and / or The hard monomer includes one or more of methyl methacrylate, styrene, acrylonitrile, and glycidyl methacrylate.

[0042] In the embodiment of the present application, the polyacrylate adhesive uses isooctyl acrylate as a soft monomer. The polyacrylate adhesive needs to be used on photovoltaic modules, and the photovoltaic modules need to experience high and low temperatures outdoors for a long time. The extreme low temperature outdoors may reach -40°C. The glass transition temperature of ethyl acrylate is about -22°C, butyl acrylate is about -55°C, and isooctyl acrylate is about -70°C. Butyl acrylate and isooctyl acrylate are more resistant to extreme low temperatures outdoors. In areas with mild climates, ethyl acrylate and butyl acrylate can also be used. The corresponding material can be selected according to the outdoor use scenario of the photovoltaic module.

[0043] In the embodiment of the present application, the types of acrylic soft monomers and hard monomers in the polyacrylate adhesive are optimized to further control the shrinkage rate and adhesion of the first battery protective film, so that effective adhesion can be continuously formed between the protective battery cell, the solar cell front protective film and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0044] In an optional embodiment, the silane monomer includes one or more of γ-methacryloxypropyltrimethoxysilane and vinyltriethoxysilane; The hydroxyl-containing monomer includes one or more of hydroxyethyl acrylate and hydroxypropyl acrylate; The carboxylic acid monomer includes one or more of acrylic acid and methacrylic acid; The epoxy monomer includes glycidyl methacrylate.

[0045] In the embodiments of the present application, the types of functional monomers in the polyacrylate adhesive are optimized to further control the shrinkage rate and adhesion of the first battery protective film, so that effective adhesion can be continuously formed between the protective battery cell, the solar cell front protective film and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0046] In an optional embodiment, the initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and tert-butyl peroxyhexahydroterephthalate.

[0047] In the embodiments of the present application, the type of initiator in the polyacrylate adhesive is optimized to further control the shrinkage rate and adhesion of the first battery protective film, so that effective adhesion can be continuously formed between the protective battery cell, the solar cell front protective film and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0048] In an optional embodiment, the cross-linking agent includes one or more of an alkoxysilane cross-linking agent, an acyloxysilane cross-linking agent, and an aminosilane cross-linking agent; and / or The coupling agent includes one or more of a silane coupling agent and a titanate coupling agent.

[0049] In the embodiment of the present application, the type of crosslinking agent and / or coupling agent in the organic silicone adhesive is optimized to further control the film quality of the second battery protective film, improve the anti-scratch effect of the solar cell front protective film, and at the same time, it is beneficial to continuously form effective bonding between the solar cell front protective film and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module. For example, the coupling agent in the organic silicone adhesive is a KH550 coupling agent (a type of titanate coupling agent), and the alkoxy group at one end of the KH550 coupling agent can undergo a condensation reaction with the silicon-oxygen bond in the organic silicone adhesive, and the amino, epoxy and other active groups at the other end can react chemically with the ester group, carboxyl group, etc. on the surface of EVA (ethylene-vinyl acetate copolymer, a type of encapsulation film) to form a chemical bond, thereby further enhancing the bonding strength; in addition, the curing shrinkage rate of the organic silicone adhesive is only 0.1%-0.5%, which can avoid the weakening of its bonding strength with the encapsulation film due to the shrinkage of the adhesive.

[0050] In an optional embodiment, the catalyst includes one or more of an organic tin compound, a phthalate catalyst, and an amine catalyst.

[0051] In the embodiments of the present application, the type of catalyst in the organic silicone adhesive is optimized to further control the film-forming quality of the second battery protective film, thereby improving the anti-scratch effect of the front protective film of the solar cell, and at the same time, it is beneficial to continuously form an effective bond between the front protective film of the solar cell and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0052] In an optional embodiment, the inorganic filler includes fumed silica, and the particle size of the fumed silica ranges from 7 to 40 nm (for example, 7 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm).

[0053] In the embodiments of the present application, the inorganic filler is fumed silica, and the inorganic filler is limited to a particle size range of fumed silica, which can reduce the content of ultraviolet rays transmitted to the light-receiving surface of the silicon substrate of the battery, ensure the stability of the Si-H bonds on the surface of the battery, and reduce the surface and bulk recombination of the battery; at the same time, by selecting a first battery protective film and a second battery protective film with different shrinkage rates, effective bonding is continuously formed between the protective battery cell, the front protective film of the solar cell, and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0054] In an optional embodiment, the dispersant includes one or more of an ionic surfactant, a nonionic surfactant, a hyperdispersant, and a low molecular weight polymer; Wherein, the ionic surfactant includes one or more of anionic surfactant and hexadecyltrimethylammonium bromide; the anionic surfactant includes one or more of sodium dodecylbenzene sulfonate and sodium dodecyl sulfate.

[0055] In the embodiments of the present application, the type of dispersant in the organic silicone adhesive is optimized to further control the film-forming quality of the second battery protective film, thereby improving the anti-scratch effect of the front protective film of the solar cell, and at the same time, it is beneficial to continuously form an effective bond between the front protective film of the solar cell and the front adhesive film, thereby ensuring the long-term reliability of the photovoltaic module.

[0056] In an optional embodiment, the solvent includes one or more of toluene, xylene, acetone, and ethyl acetate.

[0057] In the embodiment of the present application, the solvent in the polyacrylate adhesive includes one or more of toluene, xylene, acetone, and ethyl acetate; the solvent in the silicone adhesive includes one or more of toluene, xylene, acetone, and ethyl acetate; the type of solvent in the polyacrylate adhesive and the type of solvent in the silicone adhesive may be the same or different. The same type of solvent in the polyacrylate adhesive and the silicone adhesive is more conducive to improving compatibility and ensuring the interfacial bonding between the two adhesives.

[0058] In the embodiments of the present application, the types of solvents in the polyacrylate adhesive and the organic silicone adhesive are optimized, which helps to improve the wettability of the adhesive to the bonded material, thereby enhancing the bonding effect and ensuring the long-term reliability of the photovoltaic module. Taking toluene as an example, when toluene is used as a co-solvent in the preparation process of the polyacrylate adhesive and the organic silicone adhesive, the polyacrylate adhesive and the organic silicone adhesive both have a certain solubility in toluene. In addition, when the two adhesives are mixed, the organic silicone adhesive can be cured at room temperature. Therefore, the solvent volatilization process can promote the mutual diffusion and penetration of the two adhesive molecules, improve compatibility, and ensure the interfacial bonding between the two adhesives.

[0059] The present application also provides a method for preparing a solar cell front protective film, comprising: The viscosity of the polyacrylate adhesive is adjusted to 2000-3000 mPa.s (for example, 2000 mPa.s, 2100 mPa.s, 2200 mPa.s, 2300 mPa.s, 2400 mPa.s, 2500 mPa.s, 2600 mPa.s, 2700 mPa.s, 2800 mPa.s, 2900 mPa.s, 3000 mPa.s) to obtain a polyacrylate adhesive A1; the polyacrylate adhesive A1 is applied to the light-receiving surface of the solar cell body to form a polyacrylate adhesive layer, thereby obtaining a first target cell sheet; The viscosity of the organic silicone adhesive is adjusted to 3500-5000 mPa.s (for example, 3500 mPa.s, 3700 mPa.s, 3900 mPa.s, 4100 mPa.s, 4300 mPa.s, 4500 mPa.s, 4700 mPa.s, 4900 mPa.s, 5000 mPa.s) to obtain an organic silicone adhesive B1; the organic silicone adhesive B1 is applied onto the polyacrylate adhesive layer to form an organic silicone adhesive layer, and a second target battery cell is obtained; The second target cell is thermally cured to form the solar cell front protection film.

[0060] In the embodiments of the present application, optimizing the viscosity adjustment parameters in the polyacrylate adhesive and the silicone adhesive helps to improve the wettability of the adhesive to the bonded material, thereby enhancing the bonding effect and ensuring the long-term reliability of the photovoltaic module.

[0061] The following specific examples further illustrate the present application, but should not be construed as limiting the present application. Without departing from the spirit and substance of the present application, modifications or replacements made to the methods, steps or conditions of the present application are within the scope of the present application. Specific embodiments Example 1 like Figure 1 As shown, a solar cell front protection film comprises a first battery protection film 12 and a second battery protection film 13 which are stacked in sequence.

[0063] like Figure 1 As shown, an N-type back contact battery comprises an N-type back contact battery body 11, a first battery protection film 12, and a second battery protection film 13 stacked in sequence; the first battery protection film 12 is arranged on the light receiving surface (front side) of the N-type back contact battery body 11.

[0064] like Figure 2 As shown, an N-type photovoltaic module includes a KPC polymer photovoltaic back panel 5, a white high-reflective EVA packaging film 4, an N-type back contact cell 1, a front packaging film EPE 2, and an ultra-white fully tempered single-coated glass 3 stacked in sequence. Figure 2 The N-type back contact cell 1 shown is Figure 1 The N-type back contact cell shown, the N-type back contact cell 1 includes an N-type back contact cell body 11, a first cell protection film 12, and a second cell protection film 13 stacked in sequence. That is, the N-type photovoltaic module includes a KPC polymer photovoltaic back sheet 5, a white high-reflective EVA packaging film 4, an N-type back contact cell body 11, a first cell protection film 12, a second cell protection film 13, a front packaging film EPE2, and an ultra-white fully tempered single-coated glass 3 stacked in sequence. It should be noted that the white high-reflective EVA packaging film 4 can be made of ethylene-vinyl acetate copolymer; the front packaging film EPE2 can be a packaging film based on ethylene-vinyl acetate copolymer (EVA); the KPC polymer photovoltaic back sheet is a photovoltaic module back sheet, which can be a three-layer composite structure with good mechanical properties and electrical insulation.

[0065] like Figure 2 The preparation process of the N-type photovoltaic module shown is: (1) Preparation of N-type back contact cells: 1.1) Preparation of polyacrylate adhesive: 80 parts of isooctyl acrylate soft monomer, 5 parts of methyl methacrylate hard monomer, 0.2 parts of benzoyl peroxide initiator, 2 parts of KH570 monomer (γ-methacryloxypropyltrimethoxysilane, KH570 monomer as functional monomer), and 30 parts of toluene solvent are selected, and added into a reactor in sequence under the action of nitrogen as a protective gas, stirred until fully reacted, filtered and washed to obtain polyacrylate adhesive A11, and the viscosity of polyacrylate adhesive A11 is adjusted to 2000 mPa.s; 1.2) Preparation of organic silicone adhesive: 100 parts of hydroxy-terminated polydimethylsiloxane, 2 parts of methyltriethoxysilane crosslinking agent, 0.2 parts of dibutyltin dilaurate catalyst, 10 parts of fumed silica (particle size is 20 nm), 1 part of γ-aminopropyltriethoxysilane (as coupling agent), 30 parts of toluene solvent, 1 part of sodium dodecylbenzenesulfonate dispersant were selected; under the action of protective gas nitrogen, they were added into the reactor in sequence, stirred until fully reacted, filtered and washed to obtain organic silicone adhesive B11, and the viscosity of organic silicone adhesive B11 was adjusted to 3500 mPa.s; 1.3) Use ethanol to thoroughly clean the front side of the back contact solar cell body to remove grease, moisture, dust and other pollutants on the surface; then use a spray gun to spray the polyacrylate adhesive A11 to the front side of the back contact solar cell body, and control the thickness of the first battery protection film 12 to be 4 μm; use a scraping method to apply the organic silicone adhesive B11 on the surface of the first battery protection film 12, and control the thickness of the second battery protection film 13 to be twice the thickness of the first battery protection film 12, to obtain a battery cell C1; and heat cure the battery cell C1 at 120°C, and after the solvent is fully volatilized, obtain the following Figure 1 The N-type back contact battery shown; 1.4) Apply the two adhesives prepared in steps 1.1) and 1.2) on the release film at a certain thickness. After the adhesives are completely cured, verify and test the changes in light transmittance after the two adhesives are covered.

[0066] (2) After laser slicing the N-type back contact cell in step 1.3), the layers are stacked according to the normal photovoltaic module production process. The back of the N-type back contact cell 1 is stacked with a white high-reflective EVA encapsulation film 4 and a KPC polymer photovoltaic back sheet 5 in sequence, and the front of the N-type back contact cell 1 is stacked with a front encapsulation film EPE2 and an ultra-white fully tempered single-coated glass 3 in sequence; wherein the front uses a gram weight of 380g / m 2 EPE packaging film, the back side uses a weight of 400g / m 2The back of the photovoltaic module is made of white EVA encapsulation film, and the back side is made of KPC polymer photovoltaic backplane with a thickness of 300μm; after lamination, EL detection equipment is used (mainly used for the detection of photovoltaic modules, and the defects and damage inside the photovoltaic modules are detected by the principle of electroluminescence, such as crystal defects, bubbles, cracks and other problems.) to check the defective proportion of the surface of the battery cell 1; lamination is carried out according to the lamination process parameters of the photovoltaic module, and after lamination, the defective proportion of the surface of the battery cell is checked by EL detection equipment 2; this section of detection is mainly to further confirm the defectiveness of the surface of the battery cell. The defectiveness of the above two defective proportions includes lamination bubbles and shrinkage caused by adhesives; continue to install the frame and junction box according to the production process of photovoltaic modules; after the potting glue and sealant are completely cured, wipe and clean the glass surface; IV test (current-voltage characteristic test) is carried out on the prepared photovoltaic module, and the initial power of the module is recorded.

[0067] Example 2 The N-type photovoltaic module of Example 2 was prepared by referring to the preparation method of Example 1, except that step 1.2) in Example 2 was as follows: 100 parts of terminal hydroxyl polydimethylsiloxane, 2 parts of methyltriethoxysilane crosslinking agent, 0.2 parts of dibutyltin dilaurate catalyst, 15 parts of fumed silica (particle size 7 nm), 1 part of γ-aminopropyltriethoxysilane (as a coupling agent), 30 parts of toluene solvent, and 1 part of sodium dodecylbenzenesulfonate dispersant were selected; under the action of protective gas nitrogen, they were added into the reactor in turn, stirred until fully reacted, filtered and washed to obtain organic silicone adhesive B11, and the viscosity of organic silicone adhesive B11 was adjusted to 3500 mPa.s.

[0068] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0069] Example 3 The N-type photovoltaic module of Example 3 was prepared by referring to the preparation method of Example 1, except that step 1.2) in Example 3 was as follows: 100 parts of terminal hydroxyl polydimethylsiloxane, 2 parts of methyltriethoxysilane crosslinking agent, 0.2 parts of dibutyltin dilaurate catalyst, 15 parts of fumed silica (particle size 40 nm), 1 part of γ-aminopropyltriethoxysilane (as a coupling agent), 30 parts of toluene solvent, and 1 part of sodium dodecylbenzenesulfonate dispersant were selected; under the action of protective gas nitrogen, they were added into the reactor in turn, stirred until fully reacted, filtered and washed to obtain organic silicone adhesive B11, and the viscosity of organic silicone adhesive B11 was adjusted to 3500 mPa.s.

[0070] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0071] Example 4 The N-type photovoltaic module of Example 4 is prepared by referring to the preparation method of Example 1, with the only difference being that in Example 4, the thickness of the first battery protection film 12 and the second battery protection film 13 are controlled to be 50 μm as a whole. Specifically, the thickness of the first battery protection film 12 is controlled to be 16.7 μm by spraying, and the thickness of the second battery protection film 13 is controlled to be 33.3 μm by scraping.

[0072] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0073] Example 5 The N-type photovoltaic module of Example 5 is prepared by referring to the preparation method of Example 1, with the only difference being that in Example 5, the thickness of the first battery protection film 12 and the second battery protection film 13 are controlled to be 100 μm as a whole. Specifically, the thickness of the first battery protection film 12 is controlled to be 33.3 μm by spraying, and the thickness of the second battery protection film 13 is controlled to be 66.7 μm by scraping.

[0074] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0075] Comparative Example 1 The N-type photovoltaic module of Comparative Example 1 is prepared by referring to the preparation method of Example 1, except that the solar cell front protection film in Comparative Example 1 only includes the first cell protection film 12 .

[0076] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0077] Comparative Example 2 The N-type photovoltaic module of Comparative Example 2 is prepared by referring to the preparation method of Example 1, except that the solar cell front protection film in Comparative Example 2 only includes the second cell protection film 13 .

[0078] In addition, the preparation method of the N-type back contact cell is the same as that in Example 1, and the preparation method of the N-type photovoltaic module is the same as that in Example 1; after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 1; lamination is performed according to the lamination process parameters of the photovoltaic module, and after lamination, an EL detection device is used to check the defective proportion of the battery cell surface 2; the framing and junction box are installed according to the production process of the photovoltaic module; after the potting glue and the sealant are completely cured, the glass surface is wiped clean; the prepared photovoltaic module is subjected to an IV test, and the initial power of the module is recorded.

[0079] The photovoltaic modules prepared in the above embodiments and comparative examples were subjected to performance tests, and the results are shown in Tables 1 and 2.

[0080] The test items and methods are as follows: 1. The light transmittance test after the adhesive is cured shall be carried out in accordance with GB / T2410-2008; 2. The scratch effect test after the adhesive is cured is carried out in accordance with ISO 4696; 3. Membrane surface quality judgment standard: Qualified: There are no dark lines on the membrane surface, no uneven coating, no horizontal and vertical lines, no point defects and surface defects, no scratches, bubbles, etc.; 4. Photovoltaic modules shall be tested according to the "double 85" test in the IEC61215 standard (also called DH test, i.e., 1000 hours of damp heat aging test on photovoltaic modules at a temperature of 85°C and a relative humidity of 85%), 60KWh / m 2 UV test under certain conditions (UV pretreatment test), test the module power and observe whether the module appearance is abnormal.

[0081]

[0082] Data description: 1. After the scratch resistance test, observe the front of the battery under a microscope with a magnification of 500 times; 2. The statistical method for the percentage of defective film surface is as follows: 100 cells covered with protective film are cast, and the damage on the front of the cells is observed with a microscope after the corresponding process is completed. Since both human judgment and data statistics have certain errors, data deviation within the range of ±0.3% is considered normal; 3. DH1000H and UV60KWh / m 2 After power attenuation, the standard requirement is <1%.

[0083] Referring to the test data of the above-mentioned Examples 1-3, it can be seen that when the particle size of the fumed silica is 20nm, its light transmittance is the highest, but when the particle size of the fumed silica is 7nm and 40nm, its light transmittance decreases to varying degrees. This is because the fumed silica with a small particle size has a weaker scattering effect, which has less obstruction to visible light and is more conducive to maintaining the optical transparency of the system; the fumed silica with a large particle size has a stronger scattering effect on light, which reduces the transparency of the system and affects the conversion efficiency of the battery cell and the power of the photovoltaic module. However, when the particle size of the fumed silica is too small, the tendency of the particles to agglomerate increases, affecting the light transmittance of the adhesive layer. At the same time, due to the addition of fumed silica particles, it forms more bonding points and interface effects with the matrix, showing a more excellent reinforcement effect, improving the strength, hardness and wear resistance of the organic silicone adhesive, and protecting the positive surface of the battery cell from scratches or damage caused by various external factors.

[0084] From the test data of Comparative Example 1 and the embodiment, it can be seen that the addition of organic silicone adhesive improves the overall moisture and heat resistance and UV resistance of the battery. This is because the organic silicone molecular structure contains Si-O bonds, which have high bond energy and good thermal stability and weather resistance, making it resistant to ultraviolet erosion to a certain extent. Experiments have shown that organic silicone adhesive has better resistance to UV60KWh / m 2 After aging, it can still maintain good bonding and physical properties. In addition, adding fumed silica to the silicone adhesive system can scatter, reflect and absorb ultraviolet rays due to its nano-scale particle size and special surface structure, thereby reducing the transmittance of ultraviolet rays and the ultraviolet energy reaching the inside of the material.

[0085] It can be seen from the test data of Comparative Example 1, Comparative Example 2 and Example 1 that the light transmittance is slightly reduced when a single adhesive layer is used. This is because the use of two layers of adhesive with different refractive indices forms a light trapping effect on the surface of the cell, which is beneficial to increase the cell's absorption rate of light, thereby increasing the power of the photovoltaic module.

[0086] To summarize, the solar cell front protection film of the present application includes a first battery protection film and a second battery protection film stacked in sequence, which have the functions of low fluidity, high light transmittance, scratch resistance, strong adhesion to the battery surface, effective protection of the battery front, good adhesion to the front packaging film, can be directly stacked with the front packaging film, does not need to be torn off after use, will not reduce production efficiency, UV resistance, moisture and heat resistance, etc., and through material selection and structural design, it can increase the light trapping effect of solar cells, improve the conversion efficiency of solar cells and the power of components.

[0087] The embodiment of the present application can provide a back contact battery, including: The solar cell front protection film as described above; or The solar cell front protection film prepared by the above-mentioned preparation method has the same advantages as the above-mentioned solar cell front protection film, and the back contact cell also has them.

[0088] The present application embodiment may provide a photovoltaic assembly, including: At least one battery string (not shown), the battery string comprising at least two back-contact batteries as described above. The photovoltaic module also has the advantages of the back-contact batteries described above.

[0089] The embodiment of the present application can provide a photovoltaic system, including the photovoltaic components as described above. The advantages of the photovoltaic components described above are also possessed by the photovoltaic system, which will not be repeated here. The application field of the photovoltaic system described above is wide, not only limited to photovoltaic power stations, such as ground power stations, rooftop power stations and water power stations, but also includes various equipment and devices that use solar energy to generate electricity, such as user solar power supplies, solar street lights, solar cars and solar buildings. Of course, it can be understood that the application scenarios of the photovoltaic system are not limited to this, that is to say, the photovoltaic system can be used in all fields where solar energy is required for power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a junction box and an inverter. The photovoltaic array may be an array combination of multiple photovoltaic components. For example, multiple photovoltaic components may form multiple photovoltaic arrays. The photovoltaic array is connected to the junction box. The junction box can converge the current generated by the photovoltaic array. The converged current flows through the inverter and is converted into the alternating current required by the mains power grid and then connected to the mains network to realize solar power supply.

[0090] It should be noted that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present application. The orientation words "inside" and "outside" refer to the inside and outside relative to the outline of each component itself. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Therefore, the exemplary term "above..." can include both "above..." and "below..." orientations. The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used here are interpreted accordingly.

[0091] It should also be noted that "one embodiment", "another embodiment", "embodiment", etc. mentioned in this application refer to the specific features, structures or characteristics described in conjunction with the embodiment included in at least one embodiment generally described in this application. The same expression appearing in multiple places in the specification does not necessarily refer to the same embodiment. Further, when describing a specific feature, structure or characteristic in conjunction with any embodiment, it is claimed that the realization of such feature, structure or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0092] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0093] It should also be noted that the above are only preferred embodiments of the present application, and the patent protection scope of the present application is not limited thereto. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A solar cell front protective film, characterized in that: It comprises a first battery protection film and a second battery protection film stacked in sequence; the first battery protection film is in direct contact with the light-receiving surface of the solar cell body; The first battery protection film is made of polyacrylate adhesive; The second battery protection film is made based on organic silicone adhesive.

2. The solar cell front protection film according to claim 1, characterized in that: The sum of the thickness of the first battery protection film and the second battery protection film is 10 μm to 100 μm; The thickness ratio of the first battery protection film to the second battery protection film is 1:1.8~1:2.

2.

3. The solar cell front protection film according to claim 1, characterized in that: The polyacrylate adhesive comprises, by weight: 80-100 parts of acrylic soft monomer, 5-10 parts of hard monomer, 0.1-0.5 parts of initiator, 1-10 parts of functional monomer, and 20-50 parts of solvent; wherein the functional monomer comprises one or more of silane monomer, hydroxyl-containing monomer, carboxylic acid monomer, and epoxy monomer; and / or The organic silicone adhesive comprises, by weight: 80-100 parts of terminal hydroxyl polydimethylsiloxane, 1-5 parts of a cross-linking agent, 0.2-0.5 parts of a catalyst, 10-20 parts of an inorganic filler, 1-5 parts of a coupling agent, 20-50 parts of a solvent, and 1-5 parts of a dispersant.

4. The solar cell front protection film according to claim 3, characterized in that: The acrylic soft monomer includes one or more of ethyl acrylate, butyl acrylate, and isooctyl acrylate; and / or The hard monomer includes one or more of methyl methacrylate, styrene, acrylonitrile, and glycidyl methacrylate.

5. The solar cell front protection film according to claim 3, characterized in that: The silane monomers include one or more of γ-methacryloxypropyltrimethoxysilane and vinyltriethoxysilane; The hydroxyl-containing monomer includes one or more of hydroxyethyl acrylate and hydroxypropyl acrylate; The carboxylic acid monomer includes one or more of acrylic acid and methacrylic acid; The epoxy monomer includes glycidyl methacrylate.

6. The solar cell front protection film according to claim 3, characterized in that: The initiator includes one or more of azobisisobutyronitrile, azobisisoheptanenitrile, benzoyl peroxide, and tert-butyl peroxyhexahydroterephthalate.

7. The solar cell front protection film according to claim 3, characterized in that: The cross-linking agent includes one or more of an alkoxysilane cross-linking agent, an acyloxysilane cross-linking agent, and an aminosilane cross-linking agent; and / or The coupling agent includes one or more of a silane coupling agent and a titanate coupling agent.

8. The solar cell front protection film according to claim 3, characterized in that: The catalyst includes one or more of an organic tin compound, a phthalate catalyst, and an amine catalyst.

9. The solar cell front protection film according to claim 3, characterized in that: The inorganic filler includes fumed silica, and the particle size of the fumed silica ranges from 7 to 40 nm.

10. The solar cell front protection film according to claim 3, characterized in that: The dispersant includes one or more of an ionic surfactant, a nonionic surfactant, a hyperdispersant, and a low molecular weight polymer; Wherein, the ionic surfactant includes one or more of anionic surfactant and hexadecyltrimethylammonium bromide; the anionic surfactant includes one or more of sodium dodecylbenzene sulfonate and sodium dodecyl sulfate.

11. The solar cell front protection film according to claim 3, characterized in that: The solvent includes one or more of toluene, xylene, acetone, and ethyl acetate.

12. A method for preparing a solar cell front protective film according to any one of claims 1 to 11, characterized in that: include: The viscosity of the polyacrylate adhesive is adjusted to 2000-3000 mPa.s to obtain polyacrylate adhesive A1; Applying the polyacrylate adhesive A1 onto the light-receiving surface of the solar cell body to form a polyacrylate adhesive layer, thereby obtaining a first target cell sheet; The viscosity of the organic silicone adhesive is adjusted to 3500-5000 mPa.s to obtain the organic silicone adhesive B1; the organic silicone adhesive B1 is coated on the polyacrylate adhesive layer to form an organic silicone adhesive layer to obtain a second target battery cell; The second target cell is thermally cured to form the solar cell front protection film.

13. A back contact battery, characterized in that: include: The solar cell front protection film according to any one of claims 1 to 11; or The solar cell front protective film prepared by the preparation method as claimed in claim 12.

14. A photovoltaic module, characterized in that: include: At least one battery string comprising at least two back-contact batteries as claimed in claim 13.

15. A photovoltaic system, characterized in that: Comprising the photovoltaic module as claimed in claim 14.

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