High-light-transmittance weather-resistant photovoltaic packaging material and self-adaptive laminating process

Abstract

The invention relates to the technical field of photovoltaic packaging materials and self-adaptive lamination processes, and discloses a high-light-transmittance weather-proof photovoltaic packaging material and a self-adaptive lamination process, and the high-light-transmittance weather-proof photovoltaic packaging material comprises the steps of PVDF film plasma activation, ultra-thin glass chemical strengthening, ultra-thin glass antireflection coating, POE adhesive film pre-crosslinking treatment, lamination assembly, vacuum lamination and cooling solidification. The light transmission of the photovoltaic packaging material can be improved through the lamination process.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of photovoltaic packaging materials and adaptive lamination processes, and particularly relates to a high-transmittance weather-resistant photovoltaic packaging material and an adaptive lamination process. BACKGROUND

[0002] With the transformation of global energy structure and the increasing call for sustainable development, photovoltaic power generation, as a clean and renewable energy form, has been widely concerned and praised. In a photovoltaic power generation system, a photovoltaic module as a core part, its packaging material is a key factor to ensure the performance and service life of the photovoltaic module.

[0003] The packaging material is mainly placed between the glass and the solar cell or between the back plate and the solar cell of the photovoltaic module, and plays an important role in packaging and protecting the solar cell. The photovoltaic module packaging material not only needs to have good weather resistance and insulation, but also needs to ensure the effective operation and long-term stability of the solar cell. The packaging material plays a high-transmittance role on the solar cell and provides the maximum light coupling efficiency.

[0004] In the process of photovoltaic power generation, the transmittance of sunlight directly affects the photoelectric conversion efficiency of the cell, and high-quality packaging materials can effectively reduce the reflection and scattering of light, so that more sunlight can directly irradiate on the solar cell, thereby improving the utilization rate of light energy.

[0005] Therefore, we propose a high-transmittance weather-resistant photovoltaic packaging material and an adaptive lamination process. SUMMARY

[0006] The purpose of the application is to improve the light transmittance of the photovoltaic packaging material, and provide a high-transmittance weather-resistant photovoltaic packaging material and an adaptive lamination process.

[0007] The technical scheme adopted by the application is as follows: The high-transmittance weather-resistant photovoltaic packaging material and the adaptive lamination process, the lamination process is: S1: PVDF film plasma activation, a low-temperature plasma generator is selected, Ar, O2 and N2 gas interfaces are configured, then a special clamp or a vacuum adsorption platform is used to develop the film surface, wrinkles are avoided to cause uneven treatment, isopropyl alcohol or deionized water is used to wipe and remove dust and organic matter residues, the PVDF film is placed into a cavity, a set gas is introduced to a working gas pressure, plasma discharge is started, and surface activation is completed according to a set parameter; S2: Super-thin glass chemical strengthening, ultrasonic cleaning and acid cleaning liquid are used to remove dust, grease and oxides on the surface of the super-thin glass, so that the surface roughness Ra is less than or equal to 0.5 nm, the glass is immersed in a molten KNO3 salt bath, K + Na + of the glass surface layer is replaced, a compressive stress layer with a depth of 30-50 microns is formed. S3: Ultra-thin glass anti-reflective coating, nano-SiO2 sol is sprayed, sintered at 300-400°C to form a porous film layer, and the film layer is cured by 365 nm ultraviolet light, and annealed at 250°C for 30 minutes to eliminate film stress and enhance weather resistance; S4: POE film pre-crosslinking treatment, adding 2% dicumyl peroxide as crosslinking agent, promoting POE molecular chain crosslinking through free radical reaction to form a three-dimensional network structure to improve weather resistance and mechanical strength, controlling the pre-crosslinking degree to be 15%-20% to avoid bubbles or slipping during lamination due to excessive flow, using segmented temperature control in the preheating stage, 80-100°C for 30 minutes to remove solvent, then heating to 100-110°C for 5 minutes to trigger DCP decomposition and start the crosslinking reaction; S5: Laminating assembly, stacking in order, ultra-thin glass, POE film, battery piece, POE film and PVDF film to ensure the edge alignment of each layer, deviation ≤±1mm; S6: Vacuum lamination, using a vacuum laminator for lamination, first lamination preheating, vacuumizing at 80-100°C to below 10Pa for 30 minutes to remove residual solvent in the film, then heating to 140-150°C, applying a pressure of 0.8-1.0MPa for 8-10 minutes to make the POE crosslinking degree reach more than 75%, and at the same time complete the hot melt bonding of the PVDF film; S7: Cooling and curing, after lamination, slowly cooling to below 50°C at a rate of 5-10°C / min to avoid delamination or warping due to thermal stress.

[0008] In a preferred embodiment of the application, the low-temperature plasma generator checks the vacuum chamber tightness before starting to ensure that the vacuum degree can be stably maintained at ≤10Pa.

[0009] In a preferred embodiment of the application, when the thickness of the PVDF film is 0.1mm, the power of the low-temperature plasma generator is 50-150W, and when the thickness of the PVDF film is greater than 0.1mm, the power of the low-temperature plasma generator is 200-300W.

[0010] In a preferred embodiment of the application, the activation treatment time of the low-temperature plasma generator is 30 seconds to 5 minutes, the O2 gas flow of the low-temperature plasma generator is controlled at 10-50sccm, and the Ar and N2 gas flow of the low-temperature plasma generator is 20-100sccm.

[0011] In a preferred embodiment of the application, the frequency of the ultrasonic cleaning is 40kHz, and the pickling solution is a mixed solution of hydrofluoric acid and nitric acid.

[0012] In a preferred embodiment of the application, the chemical strengthening of the ultra-thin glass is treated for 4-8 hours.

[0013] In a preferred mode of the application, the irradiation intensity of the ultraviolet rays during the coating curing is 300 mJ / cm2.

[0014] In summary, due to the adoption of the above technical solutions, the application has the following advantages: 1. In the application, when O2 or air plasma treatment is adopted, high active oxygen radicals react with the material surface to generate polar groups such as hydroxyl and carboxyl groups, the polar groups enhance the surface hydrophilicity, reduce the adsorption of water vapor and pollutants, thereby reducing the diffuse reflection loss of light at the interface, the hydroxyl and carboxyl groups can form hydrogen bonds or covalent bonds with the ester groups in the POE film, reducing the interface micro-bubbles, avoiding the distortion of the light refraction path, and improving the light transmittance of the photovoltaic packaging material.

[0015] 2. In the application, Ar or N2 plasma etches the material surface by high-energy ion bombardment to form a nanoscale regular microstructure, the nanoscale rough surface can lengthen the incident light path and enhance the light absorption efficiency, and the periodic microstructure forms a gradient refractive index interface to reduce the visible light reflectivity, thereby improving the light transmittance of the photovoltaic packaging material.

[0016] 3. In the application, after the PVDF film is activated by plasma, hydroxyl and carboxyl polar groups are introduced on the surface, and the silicon hydroxyl groups of the ultra-thin glass are combined through hydrogen bonds, reducing the interface micro-gap and blocking the penetration channel of water vapor and salt mist, the C-F bond of PVDF provides chemical protection against hydrolysis and resistance to acid and alkali, the compressive stress layer of the ultra-thin glass provides physical protection against impact and stress corrosion, the combination of the two forms a composite protection system and a multi-dimensional protection network, effectively resisting the hydrolysis, salt mist corrosion and mechanical stress damage in a humid environment, and improving the long-term weather resistance of the photovoltaic module in harsh environments. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 The following is a laminating process flowchart of the application. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solutions and advantages of the embodiments of the application clearer, the technical solutions in the embodiments of the application will be described clearly and completely below in conjunction with the embodiments of the application. Obviously, the described embodiments are part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0019] The following will be combined Figure 1 The high-transmittance weather-resistant photovoltaic packaging material and self-adaptive laminating process of the embodiments of the application will be described in detail. EMBODIMENT

[0020] Referring to Figure 1 , high light transmission weather resistant photovoltaic packaging material and adaptive lamination process, the lamination process is: PVDF film plasma activation, low temperature plasma generator is selected, the low temperature plasma generator checks the vacuum cavity tightness before starting, to ensure that the vacuum degree can be stably maintained ≤10Pa, when the thickness of the PVDF film is 0.1mm, the power of the low temperature plasma generator is 50-150W, when the thickness of the PVDF film is greater than 0.1mm, the power of the low temperature plasma generator is 200-300W, configure Ar, O2, N2 gas interface, then use special clamp or vacuum adsorption platform to spread the film surface, avoid wrinkles to cause uneven treatment, use isopropyl alcohol or deionized water to wipe off dust and organic matter residues, put the PVDF film into the cavity, inlet set gas to working gas pressure, start plasma discharge, complete surface activation according to set parameters; the activation treatment time of the low temperature plasma generator is 30 seconds to 5 minutes, the O2 gas flow of the low temperature plasma generator is controlled at 10-50sccm, the Ar and N2 gas flow of the low temperature plasma generator is 20-100sccm; specifically, when using O2 or air plasma treatment, high active oxygen free radicals and material surface occur oxidation reaction, generate hydroxyl and carboxyl groups and other polar groups, polar groups enhance the surface hydrophilicity, reduce water vapor and pollutant adsorption, thereby reducing the diffuse reflection loss of light at the interface, hydroxyl and carboxyl groups can form hydrogen bond or covalent bond with ester groups in POE film, reduce interface micro-bubble, avoid light refraction path distortion, improve photovoltaic packaging material light transmission; Ar or N2 plasma etches material surface by high energy ion bombardment, forms nanoscale regular microstructure, nanoscale rough surface can prolong incident light path, enhance light absorption efficiency, periodic microstructure forms gradient refractive index interface, reduces visible light reflectivity, thereby improving photovoltaic packaging material light transmission.

[0021] Referring to Figure 1 , super-thin glass chemical strengthening, ultrasonic cleaning and acid pickling solution are used to remove super-thin glass surface dust, grease and oxides, to ensure that the surface roughness Ra≤0.5nm, the glass is immersed in molten KNO3 salt bath, K + Replace the Na +, the compressive stress layer with a depth of 30-50 μm is formed; the ultrasonic cleaning frequency is 40 kHz, the pickling solution is a mixed solution of hydrofluoric acid and nitric acid; the chemical strengthening of the ultrathin glass is processed for 4-8 hours; specifically, after the PVDF film is plasma-activated, the surface is introduced with hydroxyl and carboxyl polar groups, and the silicon hydroxyl groups of the ultrathin glass are combined through hydrogen bonds, so that the interface micro gap is reduced, the penetration channels of water vapor and salt mist are blocked, the C-F bond of the PVDF provides chemical protection against hydrolysis and resistance to acid and alkali, the compressive stress layer of the ultrathin glass provides physical protection against impact and stress corrosion, the combination of the two forms a composite protection system, forms a multi-dimensional protection network, effectively resists hydrolysis, salt mist corrosion and mechanical stress damage in a humid and hot environment, and improves the long-term weather resistance of the photovoltaic module in a harsh environment.

[0022] With reference to Figure 1 , the ultrathin glass anti-reflective coating is formed by spraying nano-SiO2 sol, sintering at 300-400°C to form a porous film layer, and curing the film layer by wavelength 365 nm ultraviolet light, and annealing at 250°C for 30 minutes to eliminate film stress and enhance weather resistance; the irradiation intensity of the ultraviolet light during film coating curing is 300 mJ / cm²; specifically, by precisely controlling the film thickness, the phase difference is formed when the incident light is reflected on the upper and lower surfaces of the film, causing the reflected light to cancel each other out, which can improve the visible light transmittance and reduce the surface reflectivity.

[0023] With reference to Figure 1 , the POE adhesive film is pre-crosslinked by adding 2% dicumyl peroxide as a crosslinking agent to promote the crosslinking of the POE molecular chain through free radical reaction to form a three-dimensional network structure to improve weather resistance and mechanical strength, and the pre-crosslinking degree is controlled to be 15%-20% to avoid bubbles or slipping during lamination due to excessive flow, and the preheating stage adopts segmented temperature control, 80-100°C for 30 minutes to remove the solvent, and then heated to 100-110°C for 5 minutes to trigger the decomposition of DCP and start the crosslinking reaction; specifically, by synergistic optimization of the pre-crosslinking degree control and the segmented temperature control process, the POE adhesive film improves the mechanical strength, interface bonding stability and weather resistance while ensuring high crosslinking efficiency.

[0024] With reference to Figure 1The laminated assembly is sequentially stacked, the super-thin glass, the POE adhesive film, the battery piece, the POE adhesive film and the PVDF film ensure that the edges of each layer are aligned, and the deviation is less than or equal to ±1 mm; vacuum lamination is performed by using a vacuum laminator, preheating is performed, vacuum is extracted to below 10 Pa at 80-100 DEG C for 30 minutes, residual solvent of the adhesive film is discharged, then the temperature is raised to 140-150 DEG C, a pressure of 0.8-1.0 MPa is applied, and maintained for 8-10 minutes, so that the cross-linking degree of POE is more than 75%, and the hot melt adhesion of the PVDF film is completed at the same time; cooling and solidification, after lamination, slowly cool to below 50 DEG C at a rate of 5-10 DEG C / min to avoid delamination or warping due to thermal stress; specifically, through the synergistic process of precise laminated alignment, vacuum gradient lamination and gradient cooling and solidification, the bonding strength, weather resistance and long-term stability of the photovoltaic module packaging interface are improved.

[0025] It should be noted that, in this text, relational terms such as first and second are used only to distinguish one entity or operation from another, and do not necessarily require or imply there is any such actual relationship or order between these entities or operations. Moreover, the terms "include", "contain" or any other variants thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment. Without more limitations, the element defined by the statement "including a" does not exclude the presence of other identical elements in the process, method, article or equipment including the element.

[0026] The above examples are only used to illustrate the technical solutions of the present application, and not to limit it; although the present application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. High-transparency weatherable photovoltaic encapsulant material and self-adapting lamination process, characterized in that, The laminating process is: S1: Plasma activation of PVDF film, select low-temperature plasma generator, configure Ar, O2, N2 gas interface, then use special fixture or vacuum adsorption platform to spread the film surface, avoid wrinkles leading to uneven treatment, use isopropyl alcohol or deionized water to wipe off dust and organic residues, put the PVDF film into the cavity, inlet set gas to working gas pressure, start plasma discharge, complete surface activation according to set parameters; S2: the ultra-thin glass is chemically strengthened, ultrasonic cleaning and acid cleaning liquid are used to remove the ultra-thin glass surface dust, grease and oxides, the surface roughness Ra≤0.5nm is ensured, the glass is immersed into a molten KNO3 salt bath, K + Na in the glass surface layer is replaced + , a compressive stress layer with a depth of 30-50μm is formed; S3: Anti-reflective coating of ultra-thin glass, spray nano-SiO2 sol, sinter at 300-400℃ to form porous film layer, and cure the film layer by wavelength 365nm ultraviolet, and anneal at 250℃ for 30 minutes to eliminate film stress and enhance weather resistance; S4: Pre-crosslinking treatment of POE adhesive film, add 2% dicumyl peroxide as crosslinking agent, promote POE molecular chain crosslinking through free radical reaction, form three-dimensional network structure to improve weather resistance and mechanical strength, control pre-crosslinking degree to 15%-20%, avoid bubbles or slipping during laminating due to excessive flow, use segmented temperature control in preheating stage, 80-100℃ for 30 minutes to remove solvent, then heat to 100-110℃ for 5 minutes to trigger DCP decomposition and start crosslinking reaction; S5: Stack assembly, stack in order, ultra-thin glass, POE adhesive film, battery piece, POE adhesive film and PVDF film to ensure the edge alignment of each layer, deviation ≤±1mm; S6: Vacuum laminating, use vacuum laminating machine for laminating, first laminating preheating, vacuum to below 10Pa at 80-100℃ for 30 minutes to remove adhesive film residual solvent, then heat to 140-150℃, apply 0.8-1.0MPa pressure for 8-10 minutes, make POE crosslinking degree reach more than 75%, and complete PVDF film hot melt bonding at the same time; S7: Cooling and curing, slowly cool to below 50℃ at a rate of 5-10℃ / min after laminating to avoid delamination or warping due to thermal stress.

2. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: The low-temperature plasma generator checks the vacuum cavity tightness before starting, to ensure that the vacuum degree can be stably maintained ≤10Pa.

3. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: When the thickness of the PVDF film is 0.1mm, the power of the low-temperature plasma generator is 50-150W, when the thickness of the PVDF film is greater than 0.1mm, the power of the low-temperature plasma generator is 200-300W.

4. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: The activation treatment time of the low-temperature plasma generator is 30 seconds to 5 minutes, the O2 gas flow of the low-temperature plasma generator is controlled at 10-50sccm, and the Ar and N2 gas flow of the low-temperature plasma generator is 20-100sccm.

5. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: The frequency of the ultrasonic cleaning is 40kHz, and the pickling solution is a mixed solution of hydrofluoric acid and nitric acid.

6. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: The chemical strengthening of the ultra-thin glass is treated for 4-8 hours.

7. The high-transmission weatherable photovoltaic encapsulant and adaptive lamination process of claim 1, wherein: The irradiation intensity of the ultraviolet during film coating curing is 300mJ / cm².

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