High-barrier weather-resistant solar cell front plate and preparation method thereof

Abstract

This application discloses a high-barrier weather-resistant solar cell front panel, comprising an outer weather-resistant film (1) and an inner supporting base film (2). The weather-resistant film (1) and the supporting base film (2) are bonded together by an adhesive layer (3). The weather-resistant film (1) is mainly composed of PVDF. Multiple equally spaced parallel serrated stripes (11) with an isosceles triangular cross-section are formed on both sides of the weather-resistant film (1). A protective layer (12) is formed on the surface of the serrated stripes (11) by vacuum sputtering. The serrated stripes (11) on both sides of the weather-resistant film (1) are arranged perpendicularly to each other. The weather-resistant film of the high-barrier weather-resistant solar cell front panel of this application can increase the contact area with the adhesive through the serrated stripes on its surface, thereby increasing the overall adhesion of the weather-resistant film, avoiding the problem of easy delamination of the weather-resistant film, and also having additional self-cleaning ability.

Description

Technical Field

[0001] This application belongs to the field of solar cell technology, and in particular relates to a high-barrier weather-resistant solar cell front panel and its preparation method. Background Technology

[0002] CN 102019734 A discloses a protective film and a front panel for solar cells. The protective film possesses high transparency, high UV absorption capacity, high weather resistance, and flexibility, and its coating layer does not peel off from the plastic film even when exposed to ultraviolet light. The protective film comprises a plastic film and a coating layer on the surface of the plastic film. This prior art solar cell front panel primarily focuses on its UV absorption capacity, lacking sufficient barrier properties and weather resistance.

[0003] CN 115179631 A discloses an encapsulation material and a photovoltaic module. The encapsulation material includes a fluoroplastic film and a water-blocking film, connected by a weather-resistant pressure-sensitive adhesive layer. A wear-resistant water-blocking layer is provided on the surface of the fluoroplastic film away from the water-blocking film. The fluoroplastic film undergoes low-pressure, low-temperature plasma surface treatment. The weather-resistant pressure-sensitive adhesive layer comprises acrylate pressure-sensitive adhesive, a combination of liquid ultraviolet absorbers, and a combination of solid ultraviolet absorbers. The fluoroplastic film used in the prior art front panel encapsulation material has high water permeability, poor wear resistance, low surface energy, and is prone to delamination and dust adsorption. After a period of outdoor use, this poses risks such as decreased module power generation and delamination. To avoid the water absorption and wear resistance problems of the fluoroplastic film, the prior art adds an additional water-blocking film. However, the weather resistance of the water-blocking film is weaker than that of the fluoroplastic film; the water-blocking film becomes brittle and cracks before the fluoroplastic film, and this does not fundamentally solve the defects of the fluoroplastic film.

[0004] CN 108091715 A discloses a composite film for the front panel of a solar cell, including a support layer and a PVDF coating coated on the support layer, wherein the PVDF coating is sprayed onto the surface of the support layer as a weather-resistant layer.

[0005] CN 102019734 A discloses a protective film comprising a plastic film and a coating layer on the surface of the plastic film, wherein the coating layer comprises an adhesive and core-shell zinc oxide particles dispersed in the adhesive. This prior art improves light transmittance and weather resistance through the outer coating layer. However, the weather-resistant coating on the front panel of the aforementioned prior art is too thin and located on the outermost side of the front panel, making it difficult to resist wind and sand erosion for extended periods. Wind and sand dust can easily scratch the surface and reduce light transmittance. Summary of the Invention

[0006] The technical problem to be solved by this application is to provide a high-barrier, weather-resistant solar cell front panel and its preparation method, so as to reduce or avoid the problems mentioned above.

[0007] To address the aforementioned technical problems, this application proposes a high-barrier weather-resistant solar cell front panel, comprising an outer weather-resistant film and an inner supporting base film, which are bonded together by an adhesive layer. The weather-resistant film is primarily composed of PVDF, and its two surfaces are formed with multiple equally spaced parallel serrated stripes with isosceles triangular cross-sections. A protective layer is formed on the surface of the serrated stripes by vacuum sputtering, and the serrated stripes on the two surfaces of the weather-resistant film are arranged perpendicularly to each other.

[0008] Preferably, the base of the isosceles triangle of the sawtooth stripe has a length of 5-10 μm, a vertex angle of 45-135 degrees, a height of 5-10 μm, and a minimum gap between adjacent sawtooth stripes of 0-5 μm.

[0009] Preferably, the maximum thickness of the weather-resistant film is 20-30 μm.

[0010] Preferably, the protective layer is made of silicon dioxide and has a thickness of 1-3 μm.

[0011] Preferably, the angle between the length direction of the serrated stripes and the four rectangular sides of the weather-resistant film is 45 degrees.

[0012] Preferably, the total thickness of the front plate is 125-240 μm, the thickness of the supporting base film is 100-200 μm, and the thickness of the adhesive layer is 5-10 μm.

[0013] Preferably, the supporting base film includes a substrate layer, and each of the two sides of the substrate layer has an online coating layer, and a barrier layer is sputtered to form the outer side of the online coating layer.

[0014] Preferably, the barrier layer is made of silicon dioxide and has a thickness of 200 nm.

[0015] Preferably, the online coating layer is formed by uniformly mixing acrylic resin, silica nanoparticles with a particle size of 5-10 nm, 1,4-dioxane, polyethylene oxide, and ethylene-vinyl acetate copolymer into a primer, and then curing it through online coating; the mass ratio of each component of the online coating layer is 100:(10~15):(20~30):(10~15):(5~10).

[0016] This application also provides a method for preparing a high-barrier weather-resistant solar cell front panel. The high-barrier weather-resistant solar cell front panel includes an outer weather-resistant film and an inner supporting base film. The weather-resistant film and the supporting base film are bonded together by an adhesive layer. The supporting base film includes a substrate layer, and each of the two sides of the substrate layer has an online coating layer. A barrier layer is sputtered to form on the outer side of the online coating layer. The preparation method includes a weather-resistant film preparation step, a supporting base film preparation step, and a bonding step between the supporting base film and the weather-resistant film. The weather-resistant film preparation step includes: providing a PVDF film mainly composed of PVDF; and forming multiple equally spaced parallel isosceles cross-sections on both sides of the PVDF film by hot pressing. Triangular serrated stripes; a protective layer is formed on the serrated stripes by vacuum sputtering, thereby forming a weather-resistant film; the preparation steps of the supporting base film include: using PET chips as raw materials for preparing PET film, obtaining a single-layer thick sheet through melt extrusion, preheating and longitudinally stretching into a film, and after longitudinal stretching, using a coating machine to online coat a mixture of components constituting the online coating layer on one side of the film, then stretching laterally, shaping, cooling, and winding, thereby forming an online coating layer on the film surface, and then sputtering a barrier layer composed of silicon dioxide on the outside of the online coating layer, thereby obtaining a supporting base film with an online coating layer and a barrier layer; the bonding steps of the supporting base film and the weather-resistant film include: bonding the supporting base film to the weather-resistant film together through an adhesive layer.

[0017] The weather-resistant film of the high-barrier weather-resistant solar cell front panel of this application can increase the contact area with the adhesive through the serrated stripes on its surface, thereby increasing the overall adhesion of the weather-resistant film, avoiding the problem of easy delamination of the weather-resistant film, and also having additional self-cleaning ability. Attached Figure Description

[0018] The accompanying drawings are intended only to illustrate and explain this application and do not limit the scope of this application.

[0019] Figure 1 The diagram shown is a cross-sectional schematic of the front panel of a high-barrier weather-resistant solar cell according to a specific embodiment of this application.

[0020] Figure 2 The diagram shown is a schematic representation of a specific structure of a support base film for a high-barrier, weather-resistant solar cell front panel according to a specific embodiment of this application.

[0021] Figure 3 The diagram shown is a structural schematic of a weather-resistant film that can be used in the front panel of a high-barrier weather-resistant solar cell according to a specific embodiment of this application.

[0022] Figure 4The diagram shown is a cross-sectional schematic of a weather-resistant film that can be used in the front panel of a high-barrier weather-resistant solar cell according to another specific embodiment of this application.

[0023] Figure 5 The diagram shown is a structural schematic of a weather-resistant film that can be used in the front panel of a high-barrier weather-resistant solar cell according to another specific embodiment of this application.

[0024] Figure 6 and Figure 7 They are displayed respectively Figure 5 The diagram shows the front and back sides of the weather-resistant film. Detailed Implementation

[0025] To provide a clearer understanding of the technical features, objectives, and effects of this application, specific embodiments are now described with reference to the accompanying drawings. Identical components are denoted by the same reference numerals.

[0026] like Figure 1 As shown, this application proposes a high-barrier, weather-resistant solar cell front panel, comprising an outer weather-resistant film 1 and an inner supporting base film 2, which are bonded together by an adhesive layer 3. In a specific embodiment, the total thickness of the front panel is 125-240 μm; the thickness of the weather-resistant film 1 is 20-30 μm; the thickness of the supporting base film 2 is 100-200 μm; and the thickness of the adhesive layer 3 is 5-10 μm.

[0027] A typical solar photovoltaic (PV) module consists of a front panel, solar cells, encapsulation materials, and a backsheet. PV modules are typically used outdoors, enduring wind, sun, rain, dust, and abrasion. Therefore, the performance requirements for the front panel, the light-receiving surface, are very high, requiring high light transmittance, water resistance, UV resistance, and a certain level of mechanical strength. The outermost weather-resistant film 1 of the front panel primarily serves to enhance performance, provide weather resistance, UV protection, moisture protection, low dielectric constant, and high breakdown voltage. The supporting base film 2 is adjacent to the circuit side of the solar panel; besides providing stronger support and protection, it also needs to provide stronger barrier properties to protect the internal circuitry. The adhesive layer 3 can use conventional EVA adhesive or a UV-cured adhesive.

[0028] The supporting base film 2 can be made of PET film with a visible light transmittance greater than 85%, and can be a single-layer or multi-layer structure formed by biaxial stretching. PET film provides excellent insulation, water resistance, mechanical properties, and dimensional stability. However, for solar cells, especially for mainstream CI(G)S flexible solar cells, their manufacturing process requires stronger barrier properties to protect the internal circuitry. Therefore, the requirements for the front sheet, back sheet, and even the encapsulation materials are very high, typically requiring a barrier property of 10. -3The g / m²·day level is a common approach to enhance barrier properties by increasing material thickness, which increases material cost, increases unit weight, and reduces material flexibility. Excessive thickness also leads to slippage and leakage when the edges of the substrate are bent. Current domestic encapsulation technologies struggle to achieve the required barrier properties. Even in Japan, with its advanced encapsulation technology, flexible solar cells have not yet reached mass production levels, resulting in high costs for commercially available flexible solar cells. Furthermore, their actual lifespan is slightly shorter than that of crystalline silicon solar cells due to limitations in the encapsulation process.

[0029] In view of this, Figure 2 In one specific embodiment of the supporting base film 2 shown, the supporting base film 2 includes a substrate layer 21, and each of the two sides of the substrate layer 21 has an online coating layer 22. A barrier layer 23 is sputtered to the outer side of the online coating layer 22. The thickness of the substrate layer 21 is preferably about 100-200 μm, for example, it can be made of a 188 μm biaxially oriented PET film. The barrier layer 23 is preferably made of silicon dioxide and has a thickness of 200 nm.

[0030] By setting the barrier layer 23, the barrier properties of the substrate layer 21 can be improved without increasing the thickness of the substrate layer 21, thus improving the adaptability of flexible solar cells. In order to improve the surface smoothness and enhance the adhesion of the barrier layer 23, it is preferable to perform an online coating process on both sides of the substrate layer 21 before sputtering to form the barrier layer 23, forming an online coating layer 22 with a preferred thickness of 0.1-0.3 μm on each side.

[0031] Online coating allows chemicals to be applied directly to the substrate layer 21 during the production process using an online coating machine. Online coating can be formed directly in the later stages of the substrate layer production process without the need to re-unroll the roll material. The coating is uniform, fast, efficient, and low-cost.

[0032] In one specific embodiment, the primer liquid constituting the online coating layer 22 can be applied to the thick sheet before or during the stretching of the polyester film constituting the substrate layer 21. Then, as the thick sheet is stretched into a film of the required thickness, the primer liquid coated on its surface becomes thinner as it is stretched, and is cured together with the high temperature during the stretching process to form the online coating layer 22.

[0033] In one specific embodiment, the online coating layer 22 is formed by uniformly mixing acrylic resin, silica nanoparticles with a particle size of 5-10 nm, 1,4-dioxane, polyethylene oxide, and ethylene-vinyl acetate copolymer into a primer, and then curing it through online coating.

[0034] Specifically, the mass ratio of each component in the online coating layer 22 is as follows: acrylic resin: silica nanoparticles: 1,4-dioxane: polyethylene oxide: ethylene-vinyl acetate copolymer = 100:(10~15):(20~30):(10~15):(5~10). The ethylene-vinyl acetate copolymer can be Evaflex 550 from Mitsui Chemicals, Inc. of Japan, containing 14% vinyl acetate polymer by mass.

[0035] According to the raw material weight ratio in the table below, online coating layers were prepared on both sides of a 188μm biaxially oriented PET film, and then a barrier layer composed of silicon dioxide was sputtered on the outside of the online coating layer.

[0036]

[0037] In comparison, a 200 nm thick barrier layer of silicon dioxide was directly sputtered onto each of the two surfaces of a 188 μm biaxially oriented PET film as a comparative example. Measurements showed that the 180-degree peel strength (N / 25 mm) of the barrier layers in Examples 1-5 was increased by 34.5%, 36.2%, 35.1%, 34.8%, and 36.1% respectively compared to the comparative examples.

[0038] Furthermore, regarding weather-resistant film 1, some existing weather-resistant films use PVDF (polyvinylidene fluoride) coatings, while others use fluoroplastic films. The main component of PVDF coatings is adhesive resin, and the PVDF content is limited, resulting in inferior weather resistance compared to weather-resistant films primarily composed of PVDF. However, PVDF weather-resistant films suffer from low surface energy and insufficient adhesion, leading to easy delamination. Additionally, their outer surface is not wear-resistant and easily attracts dust.

[0039] In view of this, this application proposes a weather-resistant film 1 that can be used in the front panel of the high-barrier weather-resistant solar cell of this application, such as... Figure 3-5 As shown, the weather-resistant film 1 in this specific embodiment is preferably composed of PVDF as the main component, wherein the mass content of PVDF in the weather-resistant film is greater than or equal to 90%, and ultraviolet light absorbers, wear-resistant fillers, etc. can be added to improve its performance.

[0040] Furthermore, as shown in the figure, multiple equally spaced parallel sawtooth stripes 11 with cross-sections of isosceles triangles are formed on both sides of the weather-resistant film 1. The sawtooth stripes on both sides of the weather-resistant film 1 are identical. The size ratio of the weather-resistant film 1 shown in the figure has been enlarged for easier observation and understanding. The actual size of the sawtooth stripes is relatively small, with only very small, barely perceptible texture on the surface, and does not affect the overall light transmittance of the weather-resistant film 1. In one specific embodiment, the maximum thickness of the weather-resistant film 1 is 20-30 μm.

[0041] Existing PVDF weather-resistant films suffer from low surface energy and insufficient adhesion, leading to a tendency to delaminate when bonded to the supporting base film 2 using adhesives. To overcome this problem, this application forms serrated stripes 11 on the surface of the weather-resistant film 1. The serrated stripes 11 increase the contact area with the adhesive layer 3. For example, when the apex angle of the isosceles trapezoid of the serrated stripes 11 is 60 degrees, the serrated stripes 11 can double the surface area, thereby increasing the overall adhesion of the weather-resistant film 1 and preventing the problem of easy delamination.

[0042] It should be noted that improving the overall adhesion of the weather-resistant film 1 actually only requires setting serrated stripes 11 on the inner side of the weather-resistant film 1. However, since the stripes are very small and difficult to observe, in order to facilitate assembly operations, the inventors chose to form the same serrated stripes 11 on both sides of the weather-resistant film 1 simultaneously, so that film coating operations can be performed on both sides, thereby increasing the applicability of the weather-resistant film. The inventors believed that the serrated stripes 11 originally located on the outer side did not seem to have any intended function. However, in actual laying experiments, it was found that if the scale of the serrated stripes 11 formed on the surface of the weather-resistant film 1 is smaller than a certain range, it can play a self-cleaning role, reducing the adhesion of dust to the surface of the weather-resistant film 1, and rainwater can easily wash away the attached dust. For example, in a specific embodiment, it is preferred that the length of the base of the isosceles triangle of the serrated stripe 11 is 5-10 μm, the vertex angle is 45-135 degrees, the height is 5-10 μm, and the minimum gap between adjacent serrated stripes 11 is 0-5 μm. Forming the same serrated stripes on both sides of the weather-resistant film 1 can not only reduce manufacturing costs, but also, by selecting serrated stripes within this size range, achieve better adhesion on the inner side and create excellent dust resistance on the outer side.

[0043] Furthermore, when identical sawtooth stripes 11 are formed on both sides, the sawtooth stripes 11 may reflect sunlight, reducing the utilization rate of the solar cells. For example, after flexible solar cells are integrated onto a building, their orientation cannot be adjusted. When the sun's deflection angle is exactly perpendicular to one side of the sawtooth stripe 11 surface, some light will be reflected back by that surface. Of course, this can be avoided by adjusting the installation angle of the sawtooth stripes 11 during installation, but this requires very high installation standards and is difficult to implement in practice. To avoid the problem of reduced sunlight utilization due to improper installation angles on both sides of the sawtooth stripes 11, this application proposes a special design in which the sawtooth stripes 11 on both sides of the weather-resistant film 1 are set perpendicular to each other, thereby avoiding the problem of simultaneous reflection on both sides reducing sunlight utilization.

[0044] Furthermore, the serrated stripes 11 on the surface of the weather-resistant film 1 of this application can also cause incident light to converge towards the center of the serrated stripes, so that the tilt angle of the light can be deflected to a certain extent towards a direction as perpendicular as possible to the solar cell, thereby improving the utilization rate of sunlight in the tilted state. Regarding the principle of serrated stripes converging light, the inventors have drawn on the prism film technology in the backlight panels of liquid crystal displays. Since the applicant's field happens to have many years of research and development in liquid crystal displays, the inventors were able to draw inspiration from the vastly different field of liquid crystal displays. However, such cross-disciplinary inspiration is not obvious to ordinary people skilled in the field of solar cells. Since the serrated stripes on both sides of the weather-resistant film are set perpendicular to each other, they can play a certain role in correcting the direction of light in different directions. After installation, they can modulate the direction of light under different solar altitude angles.

[0045] Furthermore, to improve the adhesion of the weather-resistant film 1 and prevent delamination, this application selects the angle between the length direction of the serrated stripes 11 and the four rectangular sides of the weather-resistant film 1 as 45 degrees, such as... Figure 5-7 As shown. Generally, solar panels are designed in a rectangular shape with four perpendicular sides. If the length direction of the sawtooth stripes 11 is perpendicular to one pair of rectangular sides of the weather-resistant film 1, then the other pair of rectangular sides will be parallel to the length direction of the sawtooth stripes 11. Since the stiffness of the sawtooth stripes 11 is different in the length and width directions, their expansion rates are also different, which can cause the pair of rectangular sides of the weather-resistant film 1 to warp and delaminate easily. In this application, the direction of the sawtooth stripes 11 is turned to form a 45-degree angle with the four rectangular sides. Therefore, the proportion of stiffness differences in different directions caused by the sawtooth stripes 11 spreading to the four rectangular sides will tend to be averaged, thus avoiding the problem of delamination of the weather-resistant film 1 caused by the setting of the sawtooth stripes 11, and further improving the structural performance of the weather-resistant film 1.

[0046] To improve the weather-resistant membrane 1's ability to resist wind and sand erosion, in another specific embodiment of this application, a protective layer 12 is formed on the surface of the sawtooth stripes 11 on the surface of the weather-resistant membrane 1 by vacuum sputtering. Preferably, the protective layer 12 is made of silicon dioxide and has a thickness of 1-3 μm.

[0047] Examples 6-11

[0048] The weather-resistant film was prepared according to the parameters in the table below.

[0049]

[0050] In Examples 6-8, the angle between the serrated stripes and the rectangular side of the weathering film is 45 degrees. In Examples 9-11, the angle between the serrated stripes and the rectangular side of the weathering film is 0 / 90 degrees, that is, the angle between the serrated stripes and one pair of rectangular sides is 0 degrees, and the angle with the other pair of rectangular sides is 90 degrees.

[0051] Comparative Examples 6-11

[0052] Comparative Examples 6-11 used a PVDF film without serrated stripes as the weather-resistant film, with the following parameters.

[0053]

[0054] The weather-resistant films of Examples 6-11 and Comparative Examples 6-11 were respectively bonded to the surface of a 188μm PET support base film. The parameter performance of each example of the weather-resistant film was measured and compared as follows.

[0055]

[0056] As can be seen from the performance parameter comparison of the above embodiments, the weathering film that can be used in the front panel of the high-barrier weathering solar cell of this application can significantly improve the adhesion performance and avoid delamination when it has serrated stripes. At the same time, it can improve the light transmittance of tilted light, increase the contact angle of the outer surface, improve the self-cleaning ability, and have excellent anti-dust adsorption properties.

[0057] The preparation method of the high-barrier weather-resistant solar cell front panel of this application is further described in detail below with reference to the accompanying drawings. As mentioned above, the high-barrier weather-resistant solar cell front panel of this application includes an outer weather-resistant film 1 and an inner supporting base film 2, which are bonded together by an adhesive layer 3. The weather-resistant film 1 is mainly composed of PVDF, and multiple equally spaced parallel serrated stripes 11 with an isosceles triangle cross-section are formed on both sides of the weather-resistant film 1. A protective layer 12 is formed on the surface of the serrated stripes 11 by vacuum sputtering. The serrated stripes 11 on both sides of the weather-resistant film 1 are arranged perpendicularly to each other.

[0058] The preparation method of this application includes a step of preparing a weather-resistant film 1, and a step of bonding a supporting base film 2 and a weather-resistant film 1. The preparation step of the weather-resistant film 1 includes:

[0059] First, a PVDF membrane mainly composed of PVDF is provided. This PVDF membrane can be a commercially available PVDF membrane with a thickness of 20-30μm, or it can be formed by melt co-extrusion and biaxial stretching of PVDF raw material particles with a mass content of ≥90%, with the addition of ultraviolet absorbers, wear-resistant fillers, etc.

[0060] Then, multiple equally spaced parallel serrated stripes 11 with isosceles triangular cross-sections are formed on both sides of the PVDF film by hot pressing. For example, two rollers with patterns matching the shape of the serrated stripes can be used, one above the other, to pass the heated PVDF film between the two rollers, and then the PVDF film is air-cooled or water-cooled to obtain the cured serrated stripes 11 on the PVDF film. The length directions of the patterns matching the shape of the serrated stripes on the surfaces of the two rollers are perpendicular to each other, thus forming mutually perpendicular serrated stripes 11 on both sides of the PVDF film. For example, if the pattern direction on the surfaces of the two rollers forms a 45-degree angle with the direction of the PVDF film's movement, serrated stripes 11 at a 45-degree angle to the four rectangular sides of the weather-resistant film can be formed.

[0061] Subsequently, a protective layer 12 is formed on the serrated stripes 11 by vacuum sputtering, thereby obtaining the weather-resistant film 1. For example, a layer of silicon dioxide with a thickness of 1-3 μm can be formed on the serrated stripes 11 by vacuum sputtering. Since the thickness of the formed protective layer 12 is relatively very thin, Figure 5 The protective layer 12 is not shown in the text. Figure 4 The protective layer 12 in the image has also been enlarged for easier understanding.

[0062] The bonding steps of the supporting base film 2 and the weather-resistant film 1 include: bonding the supporting base film 2 to the weather-resistant film 1 as a single unit via the adhesive layer 3. The supporting base film 2 can be made of PET film with a visible light transmittance greater than 85%, and can be a single-layer or multi-layer structure formed by biaxial stretching. In a preferred embodiment, the supporting base film 2 may include a substrate layer 21, with an online coating layer 22 on each of its two sides, and a barrier layer 23 sputtered onto the outer side of the online coating layer 22.

[0063] Therefore, the preparation method of this application may further include the preparation step of the supporting base film 2, including:

[0064] Using PET chips as raw material for preparing PET film, a single-layer thick sheet is obtained by melt extrusion. After preheating, it is stretched longitudinally into a film. After longitudinal stretching, a mixture of components constituting the online coating layer of this application is online coated on one side of the film by a coating machine. Then, it is stretched laterally, shaped, cooled, and wound up to form an online coating layer 22 on the film surface. Then, a barrier layer 23 composed of silicon dioxide is sputtered to form on the outside of the online coating layer 22, thereby obtaining a support base film 2 with the online coating layer 22 and the barrier layer 23.

[0065] Those skilled in the art should understand that although this application is described by way of multiple embodiments, not every embodiment contains only one independent technical solution. This description is merely for clarity, and those skilled in the art should understand the specification as a whole and consider the technical solutions involved in each embodiment as being able to be combined with each other to form different embodiments to understand the scope of protection of this application.

[0066] The above description is merely an illustrative embodiment of this application and is not intended to limit the scope of this application. Any equivalent changes, modifications, and combinations made by those skilled in the art without departing from the concept and principles of this application shall fall within the scope of protection of this application.

Claims

1. A high-barrier, weather-resistant solar cell front panel, comprising an outer weather-resistant film (1) and an inner supporting base film (2), wherein the weather-resistant film (1) and the supporting base film (2) are bonded together by an adhesive layer (3), characterized in that, The weather-resistant membrane (1) is mainly composed of PVDF. Multiple equally spaced parallel sawtooth stripes (11) with cross-sections of isosceles triangles are formed on both sides of the weather-resistant membrane (1). A protective layer (12) is formed on the surface of the sawtooth stripes (11) by vacuum sputtering. The sawtooth stripes (11) on both sides of the weather-resistant membrane (1) are arranged perpendicular to each other. The angle between the length direction of the sawtooth stripes (11) and the four rectangular sides of the weather-resistant membrane (1) is 45 degrees.

2. The front panel as described in claim 1, characterized in that, The isosceles triangle of the sawtooth stripe (11) has a base length of 5-10 μm, a vertex angle of 45-135 degrees, a height of 5-10 μm, and a minimum gap between adjacent sawtooth stripes (11) of 0-5 μm.

3. The front panel as described in claim 1, characterized in that, The maximum thickness of the weather-resistant film (1) is 20-30 μm.

4. The front panel as described in claim 1, characterized in that, The protective layer (12) is made of silicon dioxide and has a thickness of 1-3 μm.

5. The front panel as described in claim 1, characterized in that, The total thickness of the front plate is 125-240 μm, the thickness of the supporting base film (2) is 100-200 μm, and the thickness of the adhesive layer (3) is 5-10 μm.

6. The front panel as claimed in claim 1, characterized in that, The supporting base film (2) includes a substrate layer (21), and each of the two sides of the substrate layer (21) has an online coating layer (22). A barrier layer (23) is sputtered on the outer side of the online coating layer (22); the barrier layer (23) is made of silicon dioxide.

7. The front panel as described in claim 6, characterized in that, The thickness of the barrier layer (23) is 200 nm.

8. The front panel as described in claim 6, characterized in that, The online coating layer (22) is formed by uniformly mixing acrylic resin, silica nanoparticles with a particle size of 5-10 nm, 1,4-dioxane, polyethylene oxide, and ethylene-vinyl acetate copolymer into a base coat, and then curing it through online coating. The mass ratio of each component of the online coating layer (22) is 100: (10~15): (20~30): (10~15): (5~10).

9. A method for preparing a high-barrier weather-resistant solar cell front panel, wherein the high-barrier weather-resistant solar cell front panel comprises an outer weather-resistant film (1) and an inner supporting base film (2), the weather-resistant film (1) and the supporting base film (2) are bonded together by an adhesive layer (3), the supporting base film (2) comprises a substrate layer (21), each of the two sides of the substrate layer (21) has an online coating layer (22), and a barrier layer (23) is sputtered to the outer side of the online coating layer (22), characterized in that, The preparation method includes the preparation steps of the weather-resistant film (1), the preparation steps of the supporting base film (2), and the bonding steps of the supporting base film (2) and the weather-resistant film (1); wherein, the preparation steps of the weather-resistant film (1) include: providing a PVDF film mainly composed of PVDF; forming multiple equally spaced parallel serrated stripes (11) with isosceles triangle cross sections on both sides of the PVDF film by hot pressing, the serrated stripes (11) being arranged perpendicularly to each other; the angle between the length direction of the serrated stripes (11) and the four rectangular sides of the weather-resistant film (1) is 45 degrees; forming a protective layer (12) on the serrated stripes (11) by vacuum sputtering, thereby forming the weather-resistant film (1); the supporting base film (2) The preparation steps of the film include: using PET chips as raw materials for preparing PET film, obtaining a single-layer thick sheet by melt extrusion, preheating and then stretching it longitudinally into a film, and after longitudinal stretching, using a coating machine to coat a mixture of components constituting the online coating layer on one side of the film, and then stretching it laterally, shaping, cooling and winding it up, thereby forming an online coating layer (22) on the surface of the film, and then sputtering a barrier layer (23) composed of silicon dioxide on the outside of the online coating layer (22), thereby obtaining a support base film (2) with an online coating layer (22) and a barrier layer (23); the bonding steps of the support base film (2) and the weather-resistant film (1) include: bonding the support base film (2) to the weather-resistant film (1) together through an adhesive layer (3).

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