Photovoltaic module resistant to hydrofluoric acid corrosion

Abstract

The utility model discloses a photovoltaic assembly resistant to hydrofluoric acid corrosion, which comprises a metal frame and a photovoltaic panel, the metal frame is provided with a groove, the photovoltaic panel comprises a glass cover plate, and the side edge of the photovoltaic assembly is inserted into the groove of the metal frame. The exposed surface of the glass cover plate and the exposed surface of the metal frame are each sequentially provided with a bottom coating and an anti-corrosion protection coating, each bottom coating is formed by coating a transparent bottom coating agent, and after the glass cover plate is coated with the transparent bottom coating agent, concave and convex points on the surface of the glass cover plate are filled and leveled up, so that the glass cover plate forms a flat surface; the anti-corrosion protective coating is a light-transmitting coating containing a modified hydrophilic ethylene-polyvinyl fluoride copolymer; the overall thickness of the bottom coating and the anti-corrosion protective coating ranges from 1 micrometer to 10 micrometers. The photovoltaic module provided by the utility model has high light transmittance and corrosion resistance, can protect the glass cover plate and the metal frame from being in direct contact with hydrofluoric acid, and prolongs the service life of the photovoltaic module while ensuring the power generation performance of the photovoltaic module.

Description

Technical Field

[0001] The utility model relates to the photovoltaic field, in particular to a photovoltaic component resistant to hydrofluoric acid corrosion. Background Art

[0002] There is fluoride gas in the air near the electrolytic aluminum plant, which is caused by the gas emission of the electrolytic aluminum plant. Since fluorine-containing raw materials are used in the raw materials, it is inevitable that fluoride will exist in the exhaust gas for a long time. After testing, the concentration of fluoride is about 2.8mg / Nm 3 Aluminum electrolysis plants are energy-intensive industries that consume a lot of electricity during production. In addition, the country has policy requirements for energy consumption limits for the aluminum electrolysis industry. Therefore, aluminum electrolysis plants generally need to build photovoltaic power stations to reduce energy consumption indicators per unit product. Photovoltaic components include photovoltaic panels and metal frames. Metal frames are usually aluminum or aluminum alloy frames. Photovoltaic panels include cover plates, photovoltaic cells, EVA packaging materials and bottom plates. The cover plates are usually rolled coated tempered glass with high light transmittance / high strength. The main component of glass is acidic silicon dioxide, and hydrofluoric acid is one of the few acids that can react with acidic oxides. When fluoride encounters water in the air, HCL (hydrochloric acid), H 2 SO 4 (sulfuric acid),HNO 3 (nitric acid) and other substances can form water-soluble hydrofluoric acid (HF). Hydrofluoric acid will form a white mixture of water-insoluble fluorosilicic acid and orthosilicic acid with silicon dioxide, which will cause serious corrosion to the glass cover. At the same time, hydrofluoric acid will chemically react with the aluminum oxide layer on the surface of the aluminum frame of the photovoltaic module, exposing the active metal aluminum on the aluminum frame. The metal aluminum will easily combine with oxygen in the air to continue to generate aluminum oxide. At the same time, the newly generated aluminum oxide will absorb dust impurities in the air or react chemically with other gases to generate new chemical products. This cycle will cause the surface color of the aluminum profile to turn yellow and the aluminum frame to become thinner. Therefore, the environmental gas near the electrolytic aluminum plant will easily cause serious corrosion to the glass cover and aluminum frame of the photovoltaic module. Long-term corrosion will affect the power generation performance and structural performance of the photovoltaic module. Figure 1 This is the actual effect picture of photovoltaic modules and metal frames after being corroded by hydrofluoric acid.

[0003] The glass cover used in conventional photovoltaic modules is ultra-white tempered glass, with an oxynitride silicon anti-reflection film on the surface, and no anti-corrosion coating. Some manufacturers will use polysilazane super-hydrophobic materials as self-cleaning coatings on the surface. This coating has high permeability, wear resistance, hydrophobicity and certain chemical anti-corrosion properties. When it rains, rainwater can wash away dust and impurities on the surface of the photovoltaic module glass. However, in an environment containing corrosive gases such as hydrofluoric acid, dust is deposited on the surface for a long time. In a humid climate, the hydrofluoric acid formed reacts chemically with the coating containing polysilazane, which will slowly corrode the glass surface and the aluminum frame. After being corroded by HF acid, the polysilazane coating loses its hydrophobic function. Even in heavy rain, it cannot guarantee that the surface dust is completely washed away.

[0004] Therefore, it is necessary to provide a photovoltaic module that can prevent corrosion by HF acid and does not affect light transmission. Utility Model Content

[0005] The utility model aims to provide a photovoltaic module resistant to hydrofluoric acid corrosion, which has high light transmittance and strong corrosion resistance.

[0006] To achieve the above-mentioned purpose, the technical solution adopted by the utility model is to provide a photovoltaic component resistant to hydrofluoric acid corrosion, including a metal frame and a photovoltaic panel, the metal frame having a groove, the photovoltaic panel comprising a glass cover plate, the side of the photovoltaic panel being inserted into the groove of the metal frame, the exposed surfaces of the glass cover plate and the metal frame being sequentially provided with a primer layer and an anti-corrosion protective coating, the primer layer being formed by coating with a transparent primer, and after the transparent primer is coated on the glass cover plate, the concave and convex points on the surface of the glass cover plate are filled to form a flat surface of the glass cover plate; the anti-corrosion protective coating is a light-transmitting coating containing a modified hydrophilic ethylene-polyvinyl fluoride copolymer; the overall thickness of the primer layer and the anti-corrosion protective coating is 1μm-10μm.

[0007] Furthermore, the thickness of the primer layer is 0.3 μm-3 μm.

[0008] Furthermore, the anti-corrosion protective coating has a thickness of 0.7 μm-7 μm.

[0009] Furthermore, the light transmittance of the anti-corrosion protective coating is greater than 85%.

[0010] Furthermore, the metal frame is made of aluminum or aluminum alloy.

[0011] Furthermore, the anti-corrosion protective coating also contains functional additives and fillers.

[0012] Furthermore, the filler is one or two of fumed silica particles, tin oxide particles and magnesium fluoride particles, and the particle size is 0.18 μm to 0.35 μm.

[0013] Furthermore, the functional auxiliary agent includes a surfactant and a dispersant, the surfactant is a polyoxyethylene nonionic surfactant, and the dispersant is perfluorooctanoic acid ammonia or fluoroether salt.

[0014] Compared with the prior art, the utility model has the following beneficial effects: the photovoltaic module resistant to hydrofluoric acid corrosion provided by the utility model has a transparent and acid-resistant and alkali-resistant anti-corrosion protective coating containing modified hydrophilic ethylene-polyvinyl fluoride copolymer coated on the surface of the metal frame and the photovoltaic panel, which can protect the glass cover plate and the metal frame from direct contact with pollution sources such as hydrofluoric acid in the environment, and will not affect the light transmittance and power generation performance of the glass on the surface of the photovoltaic module, and will not reduce the cycle life of the metal frame. The primer is first applied under the anti-corrosion protective coating, which can improve the surface cleaning and surface repair of the glass cover plate and the metal frame to form a flat surface, and at the same time reduce the chemical potential energy of the surface of the glass cover plate and the metal frame to improve wettability. Therefore, the utility model adopts a double-coating anti-corrosion structure of the primer and the anti-corrosion protective coating, which can effectively resist the corrosion of hydrofluoric acid. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 This is a real-life effect diagram of existing photovoltaic modules after being corroded by hydrofluoric acid;

[0016] Figure 2 This is a schematic diagram of the structure of a photovoltaic module in an embodiment of the utility model;

[0017] Figure 3a This is the effect of spraying HF on a photovoltaic module without anti-corrosion protection coating three days later. Figure 3b This is a picture showing the effect of spraying HF on a photovoltaic module coated with the anti-corrosion protective coating provided by the utility model three days after spraying.

[0018] Reference numerals in the figures:

[0019] 1-metal frame; 11-groove, 2-base coating; 3-anti-corrosion protective coating; 4-photovoltaic panel, 41-glass cover. DETAILED DESCRIPTION

[0020] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0021] See also Figure 2The corrosion-resistant photovoltaic assembly provided by the utility model includes a metal frame 1 and a photovoltaic panel 4. The photovoltaic panel 4 includes a glass cover plate 41, a photovoltaic cell and a glass bottom plate in sequence, and is encapsulated with EVA material. The metal frame 1 has a groove 11. The side of the photovoltaic panel 4 is inserted into the groove 11 of the metal frame 1. The exposed surfaces of the glass cover plate 41 and the metal frame 1 are sequentially provided with a primer 2 and an anti-corrosion protective coating 3. The primer 2 is formed by coating with a transparent primer. After the transparent primer is coated on the glass cover plate 41, the concave and convex points on the surface of the glass cover plate 41 are filled to form a flat surface of the glass cover plate 41; the overall thickness of the primer 2 and the anti-corrosion protective coating 3 is 1μm-10μm, and the thickness is calculated from the flat surface of the glass cover plate 41 after filling, excluding the thickness of the concave and convex points; the anti-corrosion protective coating 3 is a light-transmitting coating containing a modified hydrophilic ethylene-polyvinyl fluoride copolymer. The metal frame 1 is preferably an aluminum or aluminum alloy frame, and the ethylene-polyvinyl fluoride copolymer (Teflon) has strong acid and alkali resistance and strong weather resistance. The modified hydrophilic ethylene-polyvinyl fluoride copolymer is light-transmissive. The transparent and hydrofluoric acid-resistant material is added to the surface of the photovoltaic panel 4 and the metal frame 1, which can protect the glass cover 41 and the metal frame 1 from direct contact with hydrofluoric acid, and will not affect the light transmittance and power generation performance of the glass on the surface of the photovoltaic panel 4, and will not reduce the cycle life of the metal frame 1. Therefore, the photovoltaic module provided by the utility model adopts a double coating structure of a primer 2 and an anti-corrosion protective coating 3, which can effectively resist the corrosion of hydrofluoric acid.

[0022] Preferably, the thickness of the primer layer 2 is preferably 0.3μm-3μm, which is also calculated from the flat surface of the glass cover plate 41 after filling, excluding the thickness of the concave and convex points; the thickness of the anti-corrosion protective coating 3 is preferably 0.7μm-7μm. The primer layer 2 is a base film formed after the transparent solvent is cured. The transparent solvent can be Dow Corning DOWSI L92-023 transparent primer as the main material, and heptane is mixed as a diluent solvent to improve the surface cleaning and surface repair of the glass cover plate 41 and the metal frame 1, while reducing the chemical potential energy of the surface of the glass cover plate 41 and the metal frame 1 and improving the wettability. The anti-corrosion protective coating 3 is a protective film formed after the anti-corrosion coating is cured. The light transmittance of the anti-corrosion protective coating 3 is greater than 85%. The anti-corrosion protective coating 3 also contains functional additives and fillers. The filler is one or two of fumed silica particles, tin oxide particles and magnesium fluoride particles, and the particle size is 0.18μm to 0.35μm. The functional additives include surfactants and dispersants, wherein the surfactant is a polyoxyethylene nonionic surfactant and the dispersant is perfluorooctanoic acid ammonia or fluoroether salt. With the help of the surfactants and dispersants, a stable HF acid corrosion-resistant coating is formed.

[0023] In a specific embodiment, the double-layer coating structure of the primer 2 and the anti-corrosion protection coating 3 can be achieved by the following method:

[0024] First, use a transparent primer to clean the surface of the glass cover plate 41 and the metal frame 1 for 3 to 5 minutes. On the one hand, it can fill the tiny bumps on the surface of the glass cover plate 41 and the metal frame 1, and on the other hand, it can increase the activity and adhesion of the surface of the glass cover plate 41 and the metal frame 1.

[0025] After the primer is completely dry, a modified hydrophilic ethylene-polyvinyl fluoride (ETFE) resin, a functional additive and an organic solvent are used to form an anticorrosive coating, and the anticorrosive coating is evenly covered on the glass cover plate 41 and the primer 2 on the surface of the metal frame 1 by roller coating, spraying or brushing. The specific preparation process of the anticorrosive coating is as follows: 30-50 parts of modified hydrophilic ethylene-polyvinyl fluoride copolymer (ETFE), 35-55 parts of solvent, 10-20 parts of filler and 3-5 parts of functional additive are added to a mixer by weight and mixed. Among them, the functional additive includes a surfactant and a dispersant, the surfactant is a polyoxyethylene nonionic surfactant, and the dispersant is perfluorooctanoic acid ammonia or fluoroether acid salt. The filler is one or two of fumed silica particles, tin dioxide particles and magnesium fluoride particles, and the particle size is 0.18μm to 0.35μm. The solvent is two or more of deionized water, dichloromethane, methanol and ethyl acetate.

[0026] The set temperature of the mixer is 30-50°C, the mixing time is 30-50 minutes, the speed of the mixer is set to 100-600rpm, and the speed is divided into stages from low to high: mixing for 10 minutes at 100rpm; mixing for 10-15 minutes at 450-500rpm; mixing for 10-25 minutes at 600rpm to obtain an anti-corrosion coating for photovoltaic modules.

[0027] Next, the protective film is cured at 100-140° C. for 30-50 minutes using a drying process, or cured at an ambient temperature of 30-80° C. for 24 hours to form a highly transparent and wear-resistant anti-corrosion protective coating.

[0028] Comparison of the effects of anti-corrosion coating on the surface of photovoltaic modules Figure 3a and Figure 3b As shown, Figure 3a The photovoltaic modules without anti-corrosion protection coating showed obvious corrosion three days after spraying HF. Figure 3b The photovoltaic module is provided with a double coating structure of a primer layer 2 and an anti-corrosion protection coating layer 3. After three days of spraying HF, no obvious corrosion occurs, and the light transmittance is good, which can effectively resist the corrosion of hydrofluoric acid.

[0029] In summary, the photovoltaic module provided by the utility model has high light transmittance and corrosion resistance, and can protect the glass cover and the metal frame from direct contact with pollution sources such as hydrofluoric acid, thereby ensuring the power generation performance of the photovoltaic module while extending the life of the photovoltaic module.

[0030] Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art may make some modifications and improvements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the definition of the claims.

Claims

1. A photovoltaic module resistant to hydrofluoric acid corrosion, comprising a metal frame and a photovoltaic panel, wherein the metal frame has a groove, the photovoltaic panel comprises a glass cover plate, and the side of the photovoltaic panel is inserted into the groove of the metal frame, characterized in that: The exposed surfaces of the glass cover plate and the metal frame are sequentially provided with a primer and an anti-corrosion protective coating, wherein the primer is formed by coating with a transparent primer, and after the transparent primer is coated on the glass cover plate, the concave and convex points on the surface of the glass cover plate are filled to form a flat surface of the glass cover plate; the anti-corrosion protective coating is a modified hydrophilic ethylene-polyvinyl fluoride copolymer light-transmitting coating, and the overall thickness of the primer and the anti-corrosion protective coating is 1 μm-10 μm.

2. The photovoltaic module according to claim 1, characterized in that: The thickness of the primer layer is 0.3 μm-3 μm.

3. The photovoltaic module according to claim 1, characterized in that: The thickness of the anti-corrosion protective coating is 0.7 μm-7 μm.

4. The photovoltaic module according to claim 1, characterized in that: The light transmittance of the anti-corrosion protective coating is greater than 85%.

5. The photovoltaic module according to claim 1, characterized in that: The metal frame is made of aluminum or aluminum alloy.

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