Light conversion adhesive film, photovoltaic module and application

Abstract

The invention belongs to the field of photovoltaic modules, and particularly relates to a light conversion adhesive film, a photovoltaic module and application. The light conversion adhesive film comprises a shielding barrier layer, a light conversion adhesive film layer arranged on one side of the shielding barrier layer and a UV shielding adhesive film layer arranged on the side, away from the light conversion adhesive film layer, of the shielding barrier layer, and the shielding barrier layer is made of one or more than two materials selected from polycarbonate, polyethylene glycol terephthalate and polyamide. The light conversion adhesive film disclosed by the invention has high-efficiency light conversion and complete ultraviolet shielding, and can meet the high adhesive property requirement of more than 60N / cm when being adhered with TCO (Transparent Conductive Oxide); the packaged HJT assembly has the characteristics of UV aging resistance and damp-heat aging resistance.

Description

Technical Field

[0001] The present invention belongs to the field of photovoltaic modules, and in particular relates to a light-converting adhesive film, a photovoltaic module and applications. Background Art

[0002] In recent years, amorphous silicon / crystalline silicon heterojunction solar cells (HJT) with intrinsic thin layers have attracted increasing attention due to their numerous advantages, including high conversion efficiency, low production energy consumption, simple process flow, symmetrical structure, low-temperature manufacturing process, high open-circuit voltage, good temperature characteristics, and no LID and PID effects. Their technological maturity and industrial scale have rapidly increased, making them the next generation of photovoltaic cell technology after TOPCon cell technology.

[0003] The surface deposited layer of HJT batteries is a special inert metal oxide indium tin oxide (TCO), which is highly hydrophobic. For HJT batteries, conventional EVA and POE packaging materials have poor adhesion with TCO after encapsulation. After composite aging, problems such as a significant decrease in adhesion and delamination are likely to occur.

[0004] HJT cells are also sensitive to ultraviolet (UV) light, prone to power degradation under UV exposure in the 280-400nm band. Traditionally, films containing photoconverting substances have been used to mitigate UV degradation in HJT modules by shielding some UV light. Organic photoconverters such as benzotriazole, rare earth complex organic-inorganic hybrid photoconverters, and quantum dots, for example, convert UV light into visible light, inhibiting it from reaching the HJT cell surface and thus reducing its impact on cell power. However, when used outdoors, current photoconverter films encapsulate components that contain photoconverters, such as the photoconverter and the film resin, exhibit poor compatibility and are prone to migration to the back of the cell. This results in a continuous decrease in the effective concentration on the front, severely impacting the film's photoconversion effectiveness and lifespan.

[0005] Patent application CN112980340A discloses an encapsulating film for encapsulating HJT batteries, a preparation method thereof, and a photovoltaic module obtained therefrom. The encapsulating film for encapsulating HJT batteries disclosed herein includes an adhesive layer and an EVA layer. The adhesive layer is mainly prepared from the following components in parts by weight: 100 parts of a base resin, 5-10 parts of a modified resin, and 1-5 parts of an auxiliary agent; the modified resin is mainly prepared by reacting a base resin, an initiator, and an adhesive monomer. The disclosed adhesive monomer includes any one or more of (meth)acrylic monomers, maleic acid, fumaric acid, itaconic acid, ethylene glycol, maleic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, itaconic anhydride, methylmaleic anhydride, and diethylhexyl maleate. The introduction of specific highly polar adhesion-enhancing modifiers, such as anhydrides and carboxylic acids, into the adhesive layer increases reactivity at the TCO interface, strengthening the adhesion between the adhesive film and the heterojunction cell and improving the peel strength between the adhesive film and the HJT cell. Furthermore, the EVA layer exhibits strong peel strength against the tempered glass or backplane surface, improving the long-term reliability and service life of the HJT module. However, this method lacks UV light shielding and is susceptible to UV-induced power degradation.

[0006] Patent application CN116265548A discloses a HJT-specific encapsulation film, its preparation method, and application. The disclosed HJT-specific encapsulation film comprises a base resin and a functional additive. The functional additive comprises any one or a combination of at least two of an acrylate polymer and its derivatives containing functional groups. The functional additive participates in a cross-linking reaction, and its molecular chain forms a cross-linked network structure with the base resin. The functional groups comprise any one or a combination of at least two of phosphorus-containing groups, amino groups, or carboxyl groups. The disclosed encapsulation film also contains a UV absorber. The encapsulation film functional additive can enhance the bonding strength of HJT cells and also has excellent UV shielding capabilities. However, the base functional groups containing phosphorus-containing groups and amino groups, such as acrylate polymers and their derivatives, have poor aging resistance and are prone to yellowing. Because UV light in the 280-400nm band can also be partially absorbed by HJT cells, it significantly impacts the power of HJT modules.

[0007] Patent application CN114958215A discloses a UV light conversion encapsulation film and its preparation method. The film comprises a UV light conversion layer and a UV cutoff layer, with the UV cutoff layer positioned adjacent to the solar cell. The UV cutoff layer comprises the following components: a matrix resin, a UV light absorber, a crosslinker, a co-crosslinker, a silane coupling agent, and an additive; while the UV light conversion layer comprises the following components: a matrix resin, a UV light converter, a crosslinker, a co-crosslinker, a silane coupling agent, and an additive. The UV light conversion encapsulation film converts light below 380 nm into visible light above 380 nm, maximizing the power of the module. It also exhibits excellent weather resistance and shields UV light that is incompletely converted or that increases penetration due to reduced conversion efficiency, extending the film's service life and enhancing its protection of the solar cell. However, the UV light converter and UV cutoff can migrate at high temperatures. The UV absorber migrates to the UV light conversion layer, absorbing UV light and affecting the UV light converter's function, resulting in a loss of light conversion. Summary of the Invention

[0008] The purpose of the present invention is to provide a light-converting adhesive film, a photovoltaic module and an application thereof that can improve the ultraviolet light shielding effect and resist aging.

[0009] In a first aspect of the present invention, a light-converting adhesive film is provided, which includes a shielding barrier layer, a light-converting adhesive film layer arranged on one side of the shielding barrier layer, and a UV shielding adhesive film layer arranged on the side of the shielding barrier layer away from the light-converting adhesive film layer, wherein the material of the shielding barrier layer is selected from one or more of polycarbonate, polyethylene terephthalate and polyamide.

[0010] In one or more embodiments, the light conversion adhesive film layer is made of a light conversion adhesive film layer composition, and the light conversion adhesive film layer composition includes a first transparent base resin, a light conversion agent, a first antioxidant, a first cross-linking agent, and a first coupling agent.

[0011] In one or more embodiments, the light-converting adhesive film layer has one or more of the following characteristics:

[0012] The first transparent matrix resin is selected from one or more of EVA, POE, PVB, TPU, silicone resin, acrylate and hyperbranched modified polyolefin resin;

[0013] The light conversion agent is selected from one or more of benzotriazole organic light conversion agents, rare earth complex organic-inorganic hybrid light conversion agents and quantum dots;

[0014] The first antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds; the hindered phenol compound is selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol), 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and 7-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenyl) propionate; the phosphite compound is selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite;

[0015] The first cross-linking agent includes a first cross-linking curing agent and a first auxiliary cross-linking agent, wherein the first cross-linking curing agent is selected from one or more of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate, and the first auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate;

[0016] The first coupling agent is selected from one or both of vinyl tris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

[0017] In one or more embodiments, the light-converting adhesive film layer has one or more of the following characteristics:

[0018] The first transparent matrix resin is selected from one or more of EVA, POE and PVB;

[0019] The light conversion agent is selected from one or more of 2-isobutyl-5,8-(di-tert-butylphenyl)-benzotriazole and cadmium selenide quantum dots;

[0020] The first antioxidant is selected from one or both of (4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite;

[0021] The cross-linking curing agent is tert-butyl peroxide 2-ethylhexyl carbonate, tert-amyl peroxide 2-ethylhexyl carbonate and tert-butyl peroxide 3,5,5-trimethylhexanoate;

[0022] The auxiliary cross-linking agent is triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate;

[0023] The light-converting adhesive film layer includes 80-95 parts by mass of the first transparent base resin, 0.05-2.5 parts by mass of a light-converting agent, 0.1-0.8 parts by mass of a first antioxidant, 0.3-5 parts by mass of a first crosslinking agent, and 0.3-2 parts by mass of a first coupling agent.

[0024] In one or more embodiments, the UV shielding film layer is made of a UV shielding film layer composition including a second transparent base resin, an ultraviolet absorber, a tackifying resin, a second antioxidant, a second crosslinking agent, and a second coupling agent.

[0025] In one or more embodiments, the UV shielding film layer has one or more of the following features:

[0026] The second transparent matrix resin is selected from one or more of EVA, POE, and hyperbranched modified polyolefin resins;

[0027] The ultraviolet absorber is selected from one or more of benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers and triazine ultraviolet absorbers;

[0028] The tackifying resin is selected from one or more of EVA resin grafted allyl epoxy polyether, EVA resin grafted maleic anhydride and EVA resin grafted acrylic acid;

[0029] The second antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds, the hindered phenol compounds are selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol) and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, and the phosphite compounds are selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite;

[0030] The second cross-linking agent includes a second cross-linking curing agent and a second auxiliary cross-linking agent, the second cross-linking curing agent is selected from one or more of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate, and the second auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate;

[0031] The second coupling agent is selected from one or both of vinyl tris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

[0032] In one or more embodiments, the UV shielding film layer has one or more of the following features:

[0033] The ultraviolet absorber is 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole;

[0034] The second transparent matrix resin is selected from one or two of EVA and POE;

[0035] The second antioxidant is selected from one or both of 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite;

[0036] The grafting rate of the EVA resin grafted with allyl epoxy polyether is 0.5-0.8%;

[0037] The UV shielding film layer includes 60-70 parts by mass of the second transparent base resin, 30-40 parts by mass of a tackifying resin, 0.1-1 parts by mass of an ultraviolet absorber, 0.1-1 parts by mass of a second antioxidant, 0.3-5 parts by mass of a second crosslinking agent, and 0.3-2 parts by mass of a second coupling agent.

[0038] In one or more embodiments, the light-converting adhesive film has one or more of the following characteristics:

[0039] The thickness of the light-converting adhesive film is 300-1200 μm;

[0040] The thickness of the light-converting adhesive film layer is 145-500 μm;

[0041] The thickness of the shielding barrier layer is 10-200 μm;

[0042] The thickness of the UV shielding film layer is 145-500 μm.

[0043] The second aspect of the present invention provides a photovoltaic module comprising the light-converting adhesive film described in the first aspect of the present invention; preferably, the photovoltaic module is an HJT cell; preferably, the power of the HJT cell after packaging is 715-720W.

[0044] The third aspect of the present invention provides an application selected from the group consisting of:

[0045] (1) Application of the shielding barrier layer of the present invention in the preparation of photovoltaic modules;

[0046] (2) Application of the light-converting adhesive film described in the first aspect of the present invention in improving the light conversion efficiency of photovoltaic modules;

[0047] (3) Application of the light-converting adhesive film described in the first aspect of the present invention in improving the UV shielding effect of photovoltaic modules;

[0048] (4) Application of the shielding barrier layer of the present invention in improving the UV aging resistance and / or moisture-heat aging resistance of photovoltaic modules.

[0049] The present invention has the following beneficial effects:

[0050] The light-converting film of the present invention converts the vast majority of ultraviolet light that passes through the front glass and the light-converting film layer into visible light via a light-converting agent. The remaining ultraviolet light is absorbed by the shielding barrier layer and the UV-shielding film layer. The shielding barrier layer has a densely packed lattice structure that effectively prevents the light-converting agent and the UV absorber from migrating across the shielding barrier layer. This ensures that the concentration of the light-converting agent in the light-converting film layer does not decrease due to migration, and that the UV absorber does not migrate into the film layer, thereby affecting the light-converting agent's light-converting effect.

[0051] The anti-migration light-conversion adhesive film of the present invention has the effects of ultraviolet conversion of the upper structure, ultraviolet absorption of the lower structure, and prevention of migration of the light-conversion agent and the ultraviolet absorber by the middle layer, thereby achieving complete blocking of ultraviolet light, effectively preventing power attenuation caused by ultraviolet light in HJT batteries, extending the service life of the light-conversion adhesive film, and improving the power generation efficiency of photovoltaic modules.

[0052] In summary, the light-converting adhesive film of the present invention has high-efficiency light conversion, complete UV shielding, and can achieve high bonding performance requirements of >60N / cm when bonded with TCO; the encapsulated HJT component has the characteristics of resistance to UV aging and resistance to wet heat aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 Schematic diagram of the structure of the light-converting adhesive film of the present invention, wherein a-light-converting adhesive film layer, b-shielding barrier layer, c-UV shielding adhesive film layer.

[0054] Figure 2 It is a stacking structure diagram of the HJT photovoltaic module in one or more embodiments of the present invention, wherein 1-front glass, 2-light-converting adhesive film, 3-HJT cell string, 4-high-transmittance adhesive film, 5-rear glass. DETAILED DESCRIPTION

[0055] To facilitate understanding of the features and effects of the present invention by those skilled in the art, the following provides a general description and definition of the terms and expressions used in the specification and claims. Unless otherwise indicated, all technical and scientific terms used herein have the ordinary meanings as understood by those skilled in the art regarding the present invention. In the event of conflict, the definitions in this specification shall prevail.

[0056] The theories or mechanisms described and disclosed herein, whether correct or incorrect, should not limit the scope of the present invention in any way, that is, the present invention can be implemented without being limited by any specific theory or mechanism.

[0057] Herein, “comprising,” “including,” “containing” and similar terms encompass the meanings of “consisting essentially of” and “consisting of,” for example, when “A comprises B and C” is disclosed herein, “A consists essentially of B and C” and “A consists of B and C” should be deemed to have been disclosed herein.

[0058] Throughout this document, all features, such as values, amounts, amounts, and concentrations, specified in numerical ranges or percentage ranges are provided for simplicity and convenience only. Accordingly, the description of numerical ranges or percentage ranges should be considered to encompass and specifically disclose all possible subranges and individual values ​​within those ranges (including integers and fractions).

[0059] In this document, unless otherwise specified, percentage refers to mass percentage and ratio refers to mass ratio.

[0060] Herein, when describing embodiments or examples, it should be understood that they are not intended to limit the present invention to these embodiments or examples. On the contrary, all alternatives, modifications and equivalents of the methods and materials described herein are encompassed within the scope defined by the claims.

[0061] In this document, for the sake of brevity, not all possible combinations of the various technical features in each embodiment or example are described. Therefore, as long as there are no contradictions in the combination of these technical features, the various technical features in each embodiment or example can be combined in any way, and all possible combinations should be considered to be within the scope of this specification.

[0062] Light-transmitting film

[0063] The light-converting film layer of the light-converting film of the present invention converts ultraviolet light with a wavelength of less than 400nm that passes through the glass into visible light greater than 400nm. Visible light with a wavelength greater than 400nm can pass through the shielding barrier layer and the UV shielding film layer, thereby suppressing the light attenuation caused by direct ultraviolet light irradiation on the surface of the HJT battery, while increasing the spectral absorption of the HJT battery in the visible band, and improving the conversion efficiency of the HJT. The shielding barrier layer of the light-converting film of the present invention is a transparent high-molecular polymer film material with high crystallinity or high orientation. Due to the dense arrangement of highly crystalline crystal nuclei, it can effectively prevent the diffusion and penetration of light-converting agent and ultraviolet absorber molecules. The UV shielding film layer can further absorb ultraviolet rays that pass through the light-converting film layer, while preventing the light-converting agent from aging and failing to lose its ability to convert ultraviolet rays, resulting in light attenuation caused by direct ultraviolet light irradiation on the surface of the HJT battery.

[0064] like Figure 1 As shown, the light-converting adhesive film of the present invention has a three-layer structure. One side of the UV-shielding adhesive film layer is adjacent to the HJT cell. The light-converting adhesive film of the present invention comprises a shielding barrier layer, a light-converting adhesive film layer disposed on one side of the shielding barrier layer, and a UV-shielding adhesive film layer disposed on the side of the shielding barrier layer away from the light-converting adhesive film layer. The shielding barrier layer is made of one or more materials selected from polycarbonate, polyethylene terephthalate, and polyamide.

[0065] Herein, the shielding barrier layer is a transparent high molecular polymer with high crystallinity or high orientation, which is used to protect the light-converting agent and the ultraviolet absorber from migrating with each other. The higher the crystallinity of the shielding barrier layer material, the better the orientation, the tighter the molecular arrangement, and the better the barrier property to molecules. At the same time, the material for preparing the light-converting adhesive film needs to have high light transmittance, which means that not all high crystallinity materials can be used to prepare the light-converting adhesive film. For example, polyethylene (PE) has a very high crystallinity, but its material is opaque and cannot be used to prepare the light-converting adhesive film. Those skilled in the art know that light transmittance and crystallinity / orientation are contradictory. Therefore, only materials with both high transparency and high crystallinity / orientation are suitable for the light-converting adhesive film of the present invention. Herein, the material of the shielding barrier layer is selected from one or more of polycarbonate (PC), polyethylene terephthalate (PET) and polyamide (PA).

[0066] In some embodiments, the light-converting adhesive film layer is made from a light-converting adhesive film layer composition, which includes a first transparent base resin, a light-converting agent, a first antioxidant, a first crosslinking agent, and a first coupling agent. The light-converting adhesive film layer composition can be made into the light-converting adhesive film layer using conventional methods in the photovoltaic field.

[0067] In some embodiments, the first transparent matrix resin is selected from one or more of EVA, POE, PVB, TPU, silicone resin, acrylate, and hyperbranched modified polyolefin resin. Preferably, the first transparent matrix resin is selected from one or more of EVA, POE, and PVB. Herein, the first transparent matrix resin is preferably ethylene-vinyl acetate copolymer (EVA), wherein the VA content is 20-33 wt%.

[0068] In some embodiments, the light conversion agent is selected from one or more of a benzotriazole organic light conversion agent, a rare earth complex organic-inorganic hybrid light conversion agent, and quantum dots. Preferably, the light conversion agent is selected from one or more of 2-isobutyl-5,8-(di-tert-butylphenyl)-benzotriazole and cadmium selenide quantum dots.

[0069] In some embodiments, the light conversion agent and the first transparent matrix resin are subjected to high-temperature melt mixing, twin-screw melt extrusion, underwater pelletizing, and drying to prepare a masterbatch with a light conversion agent concentration of 3-10 wt% (eg, 5 wt%).

[0070] In some embodiments, the first antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds. The hindered phenol compound is selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol), 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, and 7-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenyl) propionate. The phosphite compound is selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite, and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite. Preferably, the first antioxidant is selected from one or both of (4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite.

[0071] In some embodiments, the first cross-linking agent includes a first cross-linking curing agent and a first auxiliary cross-linking agent. The first cross-linking curing agent is selected from one or more of tert-butyl peroxidized 2-ethylhexyl carbonate, tert-amyl peroxidized 2-ethylhexyl carbonate and tert-butyl peroxidized 3,5,5-trimethylhexanoate. The first auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate. In some embodiments, the cross-linking curing agent is tert-butyl peroxidized 2-ethylhexyl carbonate, tert-amyl peroxidized 2-ethylhexyl carbonate and tert-butyl peroxidized 3,5,5-trimethylhexanoate. In some embodiments, the auxiliary cross-linking agent is triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate.

[0072] In some embodiments, the first coupling agent is selected from one or both of vinyltris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

[0073] In some embodiments, the light-converting adhesive film layer includes 80-95 parts by mass of the first transparent base resin, 0.05-2.5 parts by mass of a light-converting agent, 0.1-0.8 parts by mass of a first antioxidant, 0.3-5 parts by mass of a first crosslinking agent, and 0.3-2 parts by mass of a first coupling agent.

[0074] In some embodiments, the UV shielding film layer is made of a UV shielding film layer composition, which includes a second transparent base resin, an ultraviolet absorber, a tackifying resin, a second antioxidant, a second cross-linking agent, and a second coupling agent.

[0075] In some embodiments, the second transparent matrix resin is selected from one or more of EVA, POE, and a hyperbranched modified polyolefin resin. Preferably, the second transparent matrix resin is selected from one or more of EVA and POE. Herein, the second transparent matrix resin is preferably ethylene-vinyl acetate copolymer (EVA) having a VA content of 20-33 wt%.

[0076] In some embodiments, the UV absorber is selected from one or more of benzophenone UV absorbers, benzotriazole UV absorbers, and triazine UV absorbers. Preferably, the UV absorber is 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole.

[0077] In some embodiments, the tackifying resin is selected from one or more of EVA resin grafted with allyl epoxy polyether, EVA resin grafted with maleic anhydride, and EVA resin grafted with acrylic acid. Preferably, the grafting rate of the EVA resin grafted with allyl epoxy polyether is 0.5-0.8%, which can improve the bonding performance with TCO.

[0078] In some embodiments, the second antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds, the hindered phenol compounds are selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol) and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, and the phosphite compounds are selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite. Preferably, the second antioxidant is selected from one or more of 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl phosphite.

[0079] In some embodiments, the second cross-linking agent includes a second cross-linking curing agent and a second auxiliary cross-linking agent, the second cross-linking curing agent is selected from one or more of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate, and the second auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate.

[0080] In some embodiments, the second coupling agent is selected from one or both of vinyltris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

[0081] In some embodiments, the UV shielding film layer includes 60-70 parts by mass of the second transparent base resin, 30-40 parts by mass of a tackifying resin, 0.1-1 parts by mass of an ultraviolet absorber, 0.1-1 parts by mass of a second antioxidant, 0.3-5 parts by mass of a second crosslinking agent, and 0.3-2 parts by mass of a second coupling agent.

[0082] In some embodiments, the thickness of the light-converting adhesive film is 300-1200 μm, for example, 350 μm, 400 μm, 450 μm, 500 μm, 550 μm, 600 μm, 700 μm, or 800 μm.

[0083] In some embodiments, the thickness of the light conversion adhesive film layer is 145-500 μm, for example, 200 μm, 250 μm, 300 μm, or 400 μm.

[0084] In some embodiments, the thickness of the shielding barrier layer is 10-200 μm, for example, 50 μm, 100 μm, or 150 μm.

[0085] In some embodiments, the thickness of the UV shielding film layer is 145-500 μm, for example, 150 μm, 200 μm, 250 μm, 300 μm, or 400 μm.

[0086] Photovoltaic panels

[0087] The present invention also provides photovoltaic modules comprising the light-converting adhesive film of the present invention. In some embodiments, the photovoltaic module comprises an HJT cell. Preferably, the power of the encapsulated HJT cell is 715-720W. The light-converting adhesive film of the present invention, produced using the aforementioned formulation and processing technology, is suitable for encapsulating photovoltaic modules with various cell structures, and is particularly suitable for encapsulating HJT cell photovoltaic modules. It is also suitable for bonding laminated safety glass in the construction, automotive, and decorative industries.

[0088] application

[0089] The present invention provides an application selected from the group consisting of:

[0090] (1) Application of the shielding barrier layer of the present invention in the preparation of photovoltaic modules;

[0091] (2) Application of the light-converting adhesive film of the present invention in improving the light conversion efficiency of photovoltaic modules;

[0092] (3) Application of the light-converting adhesive film of the present invention in improving the UV shielding effect of photovoltaic modules;

[0093] (4) Application of the shielding barrier layer of the present invention in improving the UV aging resistance and / or moisture-heat aging resistance of photovoltaic modules.

[0094] Preparation method of light-converting adhesive film

[0095] A method for preparing the light-converting adhesive film of the present invention comprises the steps of:

[0096] (1) Providing a light-converting adhesive film layer composition, a UV-shielding adhesive film layer composition, and a shielding barrier layer;

[0097] (2) Compounding the light-converting adhesive film layer composition and the UV-shielding adhesive film layer composition on both sides of the shielding barrier layer.

[0098] In some embodiments, the light-converting adhesive film layer composition, the UV-shielding adhesive film layer composition, and the shielding barrier layer are as described in any embodiment herein.

[0099] In step (2), the compounding is preferably a double-film compounding. Preferably, the compounding is performed by a double-film compounding extruder.

[0100] The present invention will be further described below in conjunction with specific examples. It should be understood that these examples are intended to illustrate the present invention only and are not intended to limit the scope of the invention. The experimental methods in the following examples, for which specific conditions are not specified, are generally based on conventional conditions or the conditions recommended by the manufacturer. Unless otherwise stated, percentages and parts are calculated by weight.

[0101] In the preparation process of the light-converting adhesive film of Examples 1-3 of this article, the formula mixture of the light-converting adhesive film layer and the formula mixture of the UV shielding adhesive film layer are mixed separately and then kneaded by two independent extrusion laminating machines. Then, they are respectively laminated on the front and back of the 0.1mm thick shielding barrier layer through a T-shaped laminating head with an opening of 2mm, and then annealed, surface embossed, cooled by a cooling roller, thickness measured, and pulled before winding.

[0102] Herein, the thickness of the light-converting film layer and the UV-shielding film layer is the same.

[0103] Preparation Example 1

[0104] Preparation of light-converting agent masterbatch: 95 parts of EVA (VA content is 28wt%, melt index is 25g / 10min), and 5 parts of 2-isobutyl-5,8-(di-tert-butylphenyl)-benzotriazole as light-converting agent, mixed at 100°C for 5min, melt-extruded by a twin-screw extruder, and pelletized and dried underwater to obtain a masterbatch with a light-converting agent concentration of 5wt%.

[0105]

[0106] Preparation Example 2

[0107] Preparation of light-converting agent masterbatch: 95 parts of EVA (VA content is 28wt%, melt index is 25g / 10min), 5 parts of cadmium selenide quantum dot light-converting agent with a particle size of 2nm, kneading at 100°C for 5min, melt extrusion through a twin-screw extruder, underwater pelletizing and drying to obtain a masterbatch with a light-converting agent concentration of 5wt%.

[0108] Example 1

[0109] The formula of the light-converting adhesive film layer composition is as follows: 85 parts of EVA resin (VA content is 28wt%, melt index is 25g / 10min), 15 parts of the light-converting agent masterbatch prepared in Preparation Example 1, 0.3 parts of an antioxidant (a mixture of 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite in a molar ratio of 1:1), a cross-linking curing agent (tert-butyl peroxide 2-ethylhexyl carbonate, The present invention also comprises the following components: 1.6 parts of a mixture of tert-amyl 2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate in a molar ratio of 2:1:1), 2.0 parts of a co-crosslinking agent (a mixture of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate in a molar ratio of 1:1:1), and 1.2 parts of a silane coupling agent (a mixture of vinyl tris(β-methoxyethoxy) silane and γ-methacryloxypropyltrimethoxysilane in a molar ratio of 1:1).

[0110] The formula of the UV shielding film layer composition is as follows: 60 parts of EVA (VA content is 28wt%, melt index is 25g / 10min), 40 parts of EVA modified tackifying resin with grafting rate of 0.7%, 0.6 parts of ultraviolet absorber 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole, and a mixture of antioxidant (4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite in a molar ratio of 1:1. The present invention also comprises the following components: 1.6 parts of a cross-linking curing agent (a mixture of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate in a molar ratio of 2:1:1), 2.0 parts of a co-crosslinking agent (a mixture of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate in a molar ratio of 1:1:1), and 1.2 parts of a silane coupling agent (a mixture of vinyl tris(β-methoxyethoxy) silane and γ-methacryloxypropyltrimethoxysilane in a molar ratio of 1:1).

[0111] The shielding barrier layer is made of an optical-grade aging-resistant PET film with a thickness of 100 μm (Dongguan Runmao New Materials Co., Ltd., optical PET film).

[0112] The light-converting film layer composition and the UV-shielding film layer composition are mixed according to their respective formula ratios, and the composite light-converting film layer composition and the UV-shielding film layer composition are simultaneously coated on both sides of the shielding barrier layer film. The light-converting film layer composition and the UV-shielding film layer composition are respectively extruded and coated at a temperature of 100°C to form films. The thickness of the light-converting film layer and the UV-shielding film layer are set to be the same, and the total thickness of the film is 0.55 mm.

[0113] Example 2

[0114] The formulation of the light conversion adhesive film layer composition of Example 2 is the same as that of Example 1, except that the light conversion agent masterbatch prepared in Preparation Example 2 is used.

[0115] The formula composition of the UV shielding film layer is the same as that of Example 1.

[0116] The shielding barrier layer is the same as that in Example 1.

[0117] A film with a total thickness of 0.55 mm was prepared using the same method as in Example 1.

[0118] Example 3

[0119] The formula composition of the light-converting adhesive film layer composition and the formula composition of the UV-shielding adhesive film layer composition are the same as those in Example 1.

[0120] The shielding barrier layer is made of optical-grade aging-resistant PC film (Bofeng New Materials, optical PC film) with a thickness of 150 microns.

[0121] A film with a total thickness of 0.55 mm was prepared using the same method as in Example 1.

[0122] Comparative Example 1 (no shielding barrier layer)

[0123] The formula composition of the light-converting adhesive film layer composition and the formula composition of the UV-shielding adhesive film layer composition are the same as those in Example 1.

[0124] The light-converting film layer composition and the UV-shielding film layer composition are mixed according to their respective formula ratios, and the light-converting film layer composition and the UV-shielding film layer composition are extruded into films at a temperature of 80°C through an AB co-extrusion cast extruder. The thicknesses of the light-converting film layer and the UV-shielding film layer are set to be the same, and the total thickness of the film is 0.55 mm.

[0125] Comparative Example 2

[0126] The formula composition of the UV shielding film layer is the same as that of Example 1.

[0127] The UV shielding film layer composition was mixed according to a formula ratio, and extruded into a film at a temperature of 80° C. through a casting extruder. The film thickness was 0.55 mm.

[0128] Comparative Example 3 (using low crystalline intermediate layer)

[0129] The method of Example 1 was repeated, with the only difference being that a low-crystalline PVB film was used as the material for the shielding barrier layer, and finally a film with a total thickness of 0.55 mm was prepared.

[0130] Test Case

[0131] The method for preparing HJT components using the prepared film is as follows: stack the front glass / prepared film / HJT cell / high-transmittance film / back glass in the order of lamination, and the laminator adopts the lamination parameters of 150°C and 20 minutes for lamination, and then installs the junction box and frame to complete the component production.

[0132] Method for performing power testing on the prepared HJT component: Perform power testing on the prepared HJT component using an IV tester.

[0133] The performance evaluation results of the HJT components encapsulated using the films prepared in Examples 1-3 and Comparative Examples 1-3 are shown in Table 1.

[0134] Table 1

[0135]

[0136]

[0137] It is worth noting that since the initial power is related to high-efficiency light conversion, the light-converting film using benzotriazole-type light-converting agents has a wider absorption wavelength and high light conversion efficiency, which makes it have higher power than the components prepared with light-converting films using quantum dot-type light-converting agents. It has lower power attenuation after wet-heat aging and UV aging and better reliability.

[0138] When only a UV-shielding film layer is added, the lack of a light-converting film prevents effective utilization of UV light, resulting in low module power but relatively good reliability. When no shielding barrier layer is used, or the shielding barrier layer is a film layer with loosely arranged molecular chains, the light-converting agent easily migrates into the UV-shielding film layer. The light-converting agent and UV absorber compete for UV absorption, reducing module reliability and significantly reducing power after aging.

Claims

1. A light-converting film, characterized in that: The light-converting adhesive film includes a shielding barrier layer, a light-converting adhesive film layer arranged on one side of the shielding barrier layer, and a UV shielding adhesive film layer arranged on the side of the shielding barrier layer away from the light-converting adhesive film layer. The material of the shielding barrier layer is selected from one or more of polycarbonate, polyethylene terephthalate and polyamide.

2. The light-converting adhesive film according to claim 1, wherein: The light-converting adhesive film layer is made of a light-converting adhesive film layer composition, and the light-converting adhesive film layer composition includes a first transparent base resin, a light-converting agent, a first antioxidant, a first cross-linking agent, and a first coupling agent.

3. The light-converting adhesive film according to claim 2, wherein: The light-converting adhesive film layer has one or more of the following characteristics: The first transparent matrix resin is selected from one or more of EVA, POE, PVB, TPU, silicone resin, acrylate and hyperbranched modified polyolefin resin; The light conversion agent is selected from one or more of benzotriazole organic light conversion agents, rare earth complex organic-inorganic hybrid light conversion agents and quantum dots; The first antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds; the hindered phenol compound is selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol), 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol), octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate and 7-octadecyl-3-(4'-hydroxy-3',5'-di-tert-butylphenyl) propionate; the phosphite compound is selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite, bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite; The first cross-linking agent includes a first cross-linking curing agent and a first auxiliary cross-linking agent, wherein the first cross-linking curing agent is selected from one or more of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate, and the first auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate; The first coupling agent is selected from one or both of vinyl tris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

4. The light-converting adhesive film according to claim 3, wherein: The light-converting adhesive film layer has one or more of the following characteristics: The first transparent matrix resin is selected from one or more of EVA, POE and PVB; The light conversion agent is selected from one or more of 2-isobutyl-5,8-(di-tert-butylphenyl)-benzotriazole and cadmium selenide quantum dots; The first antioxidant is selected from one or both of (4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite; The cross-linking curing agent is tert-butyl peroxide 2-ethylhexyl carbonate, tert-amyl peroxide 2-ethylhexyl carbonate and tert-butyl peroxide 3,5,5-trimethylhexanoate; The auxiliary cross-linking agent is triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate; The light-converting adhesive film layer includes 80-95 parts by mass of the first transparent base resin, 0.05-2.5 parts by mass of a light-converting agent, 0.1-0.8 parts by mass of a first antioxidant, 0.3-5 parts by mass of a first crosslinking agent, and 0.3-2 parts by mass of a first coupling agent.

5. The light-converting adhesive film according to claim 1, wherein: The UV shielding film layer is prepared from a UV shielding film layer composition, which includes a second transparent matrix resin, an ultraviolet absorber, a tackifying resin, a second antioxidant, a second cross-linking agent and a second coupling agent.

6. The light-converting adhesive film according to claim 5, wherein: The UV shielding film layer has one or more of the following characteristics: The second transparent matrix resin is selected from one or more of EVA, POE, and hyperbranched modified polyolefin resins; The ultraviolet absorber is selected from one or more of benzophenone ultraviolet absorbers, benzotriazole ultraviolet absorbers and triazine ultraviolet absorbers; The tackifying resin is selected from one or more of EVA resin grafted allyl epoxy polyether, EVA resin grafted maleic anhydride and EVA resin grafted acrylic acid; The second antioxidant is selected from one or more of hindered phenol compounds and phosphite compounds, the hindered phenol compounds are selected from one or more of 2,2'-methylene-bis-(4-methyl-6-tert-butylphenol) and octadecyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate, and the phosphite compounds are selected from one or more of tris(2,4-di-tert-butylphenyl) phosphite and tetrakis(2,4-di-tert-butylphenyl)[1,1-phenylene]-4,4'-diylbisphosphite; The second cross-linking agent includes a second cross-linking curing agent and a second auxiliary cross-linking agent, the second cross-linking curing agent is selected from one or more of tert-butyl peroxy-2-ethylhexyl carbonate, tert-amyl peroxy-2-ethylhexyl carbonate and tert-butyl peroxy-3,5,5-trimethylhexanoate, and the second auxiliary cross-linking agent is selected from one or more of triallyl isocyanurate, trimethylolpropane triacrylate and ethoxylated pentaerythritol tetraacrylate; The second coupling agent is selected from one or both of vinyl tris(β-methoxyethoxy)silane and γ-methacryloxypropyltrimethoxysilane.

7. The light-converting adhesive film according to claim 6, wherein: The UV shielding film layer has one or more of the following characteristics: The ultraviolet absorber is 2'-(2'-hydroxy-3'-tert-butyl-5'-methylphenyl)-5-chlorobenzotriazole; The second transparent matrix resin is selected from one or two of EVA and POE; The second antioxidant is selected from one or both of 4,4'-butylene-bis-(3-methyl-6-tert-butylphenol) and bis[2,4-bis(1,1-dimethylethyl)-6-methylphenyl]ethyl ester phosphite; The grafting rate of the EVA resin grafted with allyl epoxy polyether is 0.5-0.8%; The UV shielding film layer includes 60-70 parts by mass of the second transparent base resin, 30-40 parts by mass of a tackifying resin, 0.1-1 parts by mass of an ultraviolet absorber, 0.1-1 parts by mass of a second antioxidant, 0.3-5 parts by mass of a second crosslinking agent, and 0.3-2 parts by mass of a second coupling agent.

8. The light-converting adhesive film according to claim 1, wherein: The light-converting adhesive film has one or more of the following characteristics: The thickness of the light-converting adhesive film is 300-1200 μm; The thickness of the light-converting adhesive film layer is 145-500 μm; The thickness of the shielding barrier layer is 10-200 μm; The thickness of the UV shielding film layer is 145-500 μm.

9. A photovoltaic module comprising the light conversion adhesive film according to any one of claims 1 to 8; preferably, the photovoltaic module is an HJT cell; preferably, the power of the HJT cell after packaging is 715-720W.

10. An application selected from the following group: (1) Use of the shielding barrier layer according to claim 1 in the preparation of photovoltaic modules; (2) Use of the light-converting adhesive film according to any one of claims 1 to 8 in improving the light conversion efficiency of photovoltaic modules; (3) Use of the light-converting adhesive film according to any one of claims 1 to 8 in improving the UV shielding effect of photovoltaic modules; (4) Use of the shielding barrier layer according to claim 1 in improving the UV aging resistance and / or heat and humidity aging resistance of photovoltaic modules.

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