Light conversion adhesive film and photovoltaic module

Abstract

The invention provides a light conversion adhesive film and a photovoltaic module. The light conversion adhesive film comprises matrix resin and a UV light conversion agent, wherein the surface concentration of the UV light conversion agent in the light conversion adhesive film is 0.3-2 g / m < 2 >; the UV light conversion agent comprises at least two of a first UV light conversion agent, a second UV light conversion agent and a third UV light conversion agent; the maximum absorption peak of the first UV light conversion agent is 370-380 nm, and the maximum emission peak of the first UV light conversion agent is 605-615 nm; the maximum absorption peak of the second UV light conversion agent is 350-370 nm, and the maximum emission peak of the second UV light conversion agent is 415-425 nm; the maximum absorption peak of the third UV light conversion agent is 370-405 nm, and the maximum emission peak of the third UV light conversion agent is 485-505 nm. The three UV light conversion agents with different maximum emission peak ranges are combined for use, more colors can be blended, and the output power of the photovoltaic module is remarkably improved.

Description

Technical Field

[0001] This invention relates to the field of photovoltaic technology, and more specifically, to a light-converting adhesive film and a photovoltaic module. Background Technology

[0002] Crystalline silicon photovoltaic cells have low photoelectric conversion efficiency for ultraviolet light with wavelengths of 300~400nm. These high-energy photons usually produce "thermal relaxation" energy loss, which is dissipated in the form of heat.

[0003] Currently, there are attempts to apply light-conversion films using a single fluorescent material (such as converting ultraviolet light to blue light) to photovoltaic modules. However, limitations exist: 1) Fixed and single conversion band: It cannot flexibly adapt to the differences in spectral response curves of different types of photovoltaic cells (such as PERC cells, TOPCon cells, and HJT cells). 2) Contradiction between conversion efficiency and stability: High concentrations of a single fluorescent material are prone to concentration quenching, leading to a decrease in fluorescence efficiency, while low concentrations of a single fluorescent material result in insufficient conversion. 3) Spectral mismatch loss: The spectrum after simple conversion may deviate from the optimal response spectrum of the cell, failing to maximize energy utilization. Furthermore, from an aesthetic perspective, light-conversion films with a single fluorescent color restrict the application scenarios of solar cells, especially failing to meet the aesthetic requirements of building-integrated photovoltaics (BIPV) modules.

[0004] Therefore, there is an urgent need to develop a new type of light-converting film to overcome the limitations of existing light-converting films. Summary of the Invention

[0005] The main objective of this invention is to provide a light-converting adhesive film and a photovoltaic module to solve the problems of existing light-converting adhesive films having a single conversion band, low conversion efficiency, and inability to meet the aesthetic design requirements of solar cell modules.

[0006] To achieve the above objectives, according to one aspect of the present invention, a light-converting film is provided, comprising: a matrix resin and a UV light-converting agent; wherein the areal concentration of the UV light-converting agent in the light-converting film is 0.3~2 g / m². 2 The UV light conversion agent includes at least two of a first UV light conversion agent, a second UV light conversion agent, and a third UV light conversion agent; the first UV light conversion agent has a maximum absorption peak of 370~380nm and a maximum emission peak of 605~615nm; the second UV light conversion agent has a maximum absorption peak of 350~370nm and a maximum emission peak of 415~425nm; and the third UV light conversion agent has a maximum absorption peak of 370~405nm and a maximum emission peak of 485~505nm.

[0007] Further, the first UV light conversion agent includes rare earth fluorescent materials; preferably, the rare earth fluorescent material is a europium-based rare earth fluorescent material; the europium-based rare earth fluorescent material is selected from any one or more of the following: p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, p-hydroxybenzoic acid-o-phenanthroline-europium ternary complex, p-aminobenzoic acid-o-phenanthroline-europium ternary complex, benzoic acid-o-phenanthroline-europium ternary complex, 2-thiophenecarboxyltrifluoroacetone-o-phenanthroline-europium ternary complex, and dibenzoyl-o-phenanthroline-europium ternary complex.

[0008] Furthermore, the second UV light converter includes benzotriazole fluorescent materials; the general structural formula of benzotriazole fluorescent materials is as follows: Where R substituent is Furthermore, benzotriazole fluorescent materials have at least one R substituent at positions 4 and 7, and benzotriazole derivatives have at least one R substituent at positions 5 and 6; R1 and R2 are each independently selected from H, substituted or unsubstituted C1~C1. 20 The alkyl group, at least one methylene group, is substituted with -COO- or -O- at C3~C4. 20 Alkyl, substituted or unsubstituted C2~C 20 Any one of the alkenyl groups; when there are substituents, the substituents are selected from any one or more of methyl, ethyl, propyl, butyl, trifluoromethyl, and nitro.

[0009] Furthermore, the third UV light conversion agent includes modified perovskite quantum dots, which include perovskite quantum dot material and an oxide shell coating on the outer surface of the perovskite quantum dot material. The oxide shell material is silicon dioxide and / or zinc oxide. Preferably, the perovskite quantum dot material is cesium lead bromide perovskite quantum dots and / or cesium lead chloride perovskite quantum dots.

[0010] Furthermore, the particle size of the third UV light converter is ≤10nm; and / or, the mass ratio of the oxide shell to the perovskite quantum dot material in the modified perovskite quantum dots is 0.1~2:1.

[0011] Furthermore, the transmittance of the light-converting film to ultraviolet light in the wavelength range of 280~380nm is 1~50%; and / or, the thickness of the light-converting film is 300~600μm.

[0012] Furthermore, the light-converting film also includes: a primary crosslinking agent, a secondary crosslinking agent, a silane coupling agent, a light stabilizer, and an antioxidant.

[0013] Further, by weight, the light-converting film comprises: 100 parts of matrix resin, 0.3 to 2 parts of main crosslinking agent, 0.3 to 2 parts of co-crosslinking agent, 0.1 to 2 parts of silane coupling agent, 0.1 to 1.5 parts of light stabilizer and 0.1 to 2 parts of antioxidant.

[0014] Further, the matrix resin is selected from any one or more of ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, and ethylene-methyl methacrylate copolymer; and / or, the main crosslinking agent is selected from dicumyl peroxide, benzoyl peroxide, amyl peroxide, tert-amyl 3,5,5-trimethylhexanoate peroxide, di-tert-butyl peroxide, tert-butyl isopropyl peroxide, and di-dicarbonate peroxide. Cyclohexyl ester, bis(2-phenylethoxy) peroxydicarbonate, di(2-ethylhexyl) peroxydicarbonate, bis(4-tert-butylcyclohexyl) peroxydicarbonate, tert-butyl tert-valerate peroxydicarbonate; and / or, the co-crosslinking agent is selected from at least one of triallyl 1,3,5-cyanurate, trimethylolpropane triacrylate, triallyl isocyanurate, and polytriallyl isocyanurate; and / or, the silane coupling agent is selected from γ-aminopropyltriethyl... Oxy-silane, γ-methacryloyloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, vinyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidyl etheroxypropyltrimethylsilane, 3-aminopropyltrimethylsilane; and / or, the light stabilizer is selected from 2-(2-hydroxyphenyl)-benzotriazole, succinic acid, and 4-hydroxy-2,2,6,6-tetramethyl-1 -A polymer of piperidinol, N,N-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-phenylenediamide, 2,2,6,6-tetramethylpiperidinamine, 1,3-diphenylisobenzofuran, 9,10-anthratridiyl-bis(methylene)dimalonic acid; and / or, the antioxidant is selected from any one or more of hindered phenolic antioxidants, aromatic amine antioxidants, phosphite antioxidants, thioether antioxidants, and metal passivating antioxidants.

[0015] According to another aspect of the present invention, a photovoltaic module is provided, including an encapsulating film comprising the above-described light-converting film.

[0016] By applying the technical solution of this invention, the light-converting film of this application combines at least two of the three UV light-converting agents with different maximum emission peak ranges and adjusts their proportions. This enables "precise trimming" and "on-demand conversion" of the solar spectrum, maximizing the conversion of low-utilization light such as ultraviolet light into the specific wavelengths of light most sensitive to the target photovoltaic cell, thereby significantly improving the output power of the photovoltaic module. Simultaneously, it allows for the formulation of more colors, thus meeting the diverse application scenarios of photovoltaic modules. Because the emission spectrum of one UV light-converting agent overlaps with the absorption spectrum of another, a "reabsorption" phenomenon occurs, causing severe photon loss. However, the emission peaks of the three UV light-converting agents in this application are all separated from the absorption peaks of their respective UV light-converting agents, minimizing the spectral overlap region and greatly reducing reabsorption, thereby reducing photon loss. Typically, a single UV light converter is insufficient to achieve both high-efficiency UV absorption and high-efficiency fluorescence performance. However, the three UV light converters in this application are used in combination, and by controlling the surface concentration of the UV light converters within the aforementioned range, complementary functions can be achieved, thereby improving the light utilization rate of photovoltaic modules. At the same time, more colors can be formulated, thus meeting the aesthetic design requirements of photovoltaic modules. Detailed Implementation

[0017] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the embodiments.

[0018] As analyzed in the background section of this application, existing light-converting films suffer from problems such as a single conversion band, low conversion efficiency, and inability to meet the aesthetic design requirements of solar cell modules. In order to solve the above problems, this application provides a light-converting film and a photovoltaic module.

[0019] In a typical embodiment of this application, a light-converting film is provided, comprising: a matrix resin and a UV light-converting agent; wherein the areal concentration of the UV light-converting agent in the light-converting film is 0.3~2 g / m². 2 The UV light conversion agent includes at least two of a first UV light conversion agent, a second UV light conversion agent, and a third UV light conversion agent; the first UV light conversion agent has a maximum absorption peak of 370~380nm and a maximum emission peak of 605~615nm; the second UV light conversion agent has a maximum absorption peak of 350~370nm and a maximum emission peak of 415~425nm; and the third UV light conversion agent has a maximum absorption peak of 370~405nm and a maximum emission peak of 485~505nm.

[0020] The light-converting film of this application combines at least two of the three UV light-converting agents with different maximum emission peak ranges and adjusts their proportions to achieve "precise trimming" and "on-demand conversion" of the solar spectrum. This maximizes the conversion of low-utilization light, such as ultraviolet light, into specific wavelengths of light most sensitive to the target photovoltaic cell, significantly improving the output power of the photovoltaic module. Simultaneously, it allows for the formulation of more colors, thus meeting the diverse application scenarios of photovoltaic modules. Because the emission spectrum of one UV light-converting agent overlaps with the absorption spectrum of another, a "reabsorption" phenomenon occurs, causing severe photon loss. However, the emission peaks of the three UV light-converting agents in this application are separated from their absorption peaks, minimizing the spectral overlap region and greatly reducing reabsorption, thereby reducing photon loss. Typically, a single UV light-converting agent is insufficient to achieve both high-efficiency ultraviolet absorption and high-efficiency fluorescence performance. The three UV light-converting agents in this application, used in combination and with the surface concentration controlled within the aforementioned range, achieve functional complementarity, thereby improving the light utilization rate of the photovoltaic module and allowing for the formulation of more colors, thus meeting the aesthetic design requirements of photovoltaic modules.

[0021] In one embodiment of this application, the first UV light converter includes a rare earth fluorescent material; preferably, the rare earth fluorescent material is a europium-based rare earth fluorescent material; the europium-based rare earth fluorescent material is selected from any one or more of the following: p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, p-hydroxybenzoic acid-o-phenanthroline-europium ternary complex, p-aminobenzoic acid-o-phenanthroline-europium ternary complex, benzoic acid-o-phenanthroline-europium ternary complex, 2-thiophenecarboxyltrifluoroacetone-o-phenanthroline-europium ternary complex, and dibenzoyl-o-phenanthroline-europium ternary complex.

[0022] Preferred rare-earth fluorescent materials in the first UV light converter are europium-based rare-earth fluorescent materials. Due to their ff transition characteristics, europium-based rare-earth fluorescent materials can provide highly pure red fluorescence, and this luminescence characteristic has good resistance to external environmental changes (such as temperature and humidity), thereby improving the color consistency of the light-converting film under different usage conditions. Preferring europium-based rare-earth fluorescent materials within the aforementioned range not only helps to further improve color purity and stability but also helps to effectively convert more ultraviolet photons into visible photons, thereby improving the overall photoelectric conversion efficiency of the solar cell module. Furthermore, europium-based fluorescent materials generally have good chemical stability and are not easily affected by chemical reactions, which helps to maintain the performance stability of the light-converting film and extend its service life. Preferably, the maximum absorption peak of the first UV light converter is within the aforementioned range, which helps to reduce thermal relaxation energy loss, thereby improving the energy utilization efficiency of the photovoltaic module. Simultaneously, it also helps to reduce the overlap in the absorption spectra of the first UV light converter and the second or third UV light converter, reducing energy transfer conflicts between different fluorescent materials, thus facilitating the independent performance of their respective fluorescence properties.

[0023] In one embodiment of this application, the second UV light converter comprises a benzotriazole fluorescent material; the general structural formula of the benzotriazole fluorescent material is as follows: Where R substituent is Furthermore, benzotriazole fluorescent materials have at least one R substituent at positions 4 and 7, and benzotriazole derivatives have at least one R substituent at positions 5 and 6; R1 and R2 are each independently selected from H, substituted or unsubstituted C1~C1. 20 The alkyl group, at least one methylene group, is substituted with -COO- or -O- at C3~C4. 20 Alkyl, substituted or unsubstituted C2~C 20 Any one of the alkenyl groups; when there are substituents, the substituents are selected from any one or more of methyl, ethyl, propyl, butyl, trifluoromethyl, and nitro.

[0024] The preferred second UV light converter has a benzotriazole fluorescent material with a chemical structure within the aforementioned range, which helps to efficiently absorb ultraviolet light, reduce heat loss of light energy, and thus improve photoelectric conversion efficiency. Different structures of benzotriazole fluorescent materials facilitate fine-tuning of the emission wavelength, allowing for more precise spectral matching when combined with other fluorescent materials, thereby improving spectral utilization.

[0025] Preferably, R1 and R2 are each independently selected from H, substituted or unsubstituted C1~C. 12 The alkyl group, at least one methylene group, is substituted with -COO- or -O- at C3~C4. 12 Alkyl, substituted or unsubstituted C2~C 12Any one of the alkenyl groups.

[0026] Preferably, R1 and R2 are each independently selected from H, methyl, ethyl, propyl, vinyl, propyl ester, propyl ether, propenyl, isobutyl, and tert-butyl.

[0027] Preferably, the benzotriazole fluorescent material is .

[0028] In one embodiment of this application, the third UV light conversion agent includes modified perovskite quantum dots, which include perovskite quantum dot material and an oxide shell coating the outer surface of the perovskite quantum dot material. The oxide shell material is silicon dioxide and / or zinc oxide. Preferably, the perovskite quantum dot material is cesium lead bromide perovskite quantum dots and / or cesium lead chloride perovskite quantum dots.

[0029] The oxide shell coating on the surface of the modified perovskite quantum dots helps to isolate direct contact between different fluorescent material cores, reducing chemical reactions and unfavorable energy transfer, while further suppressing concentration quenching. Cesium lead bromide perovskite quantum dots possess high fluorescence quantum yield and good thermal stability, which helps absorb light in the ultraviolet to blue light region and also helps maintain the high light conversion performance of the light-converting film. Cesium lead chloride perovskite quantum dots help to effectively absorb ultraviolet light, reducing light "thermal relaxation" losses, thereby improving the light energy conversion efficiency of photovoltaic modules.

[0030] In one embodiment of this application, the particle size of the third UV light converter is ≤10nm; and / or, the mass ratio of the oxide shell to the perovskite quantum dot material in the modified perovskite quantum dots is 0.1~2:1.

[0031] The preferred particle size of the third UV light converter is within the above-mentioned range, which helps to reduce light scattering and alleviate concentration quenching caused by energy transfer between particles at high concentrations, thereby maintaining high fluorescence efficiency. The preferred mass ratio of oxide shell to perovskite quantum dot material in the modified perovskite quantum dots is within the above-mentioned range, which helps to isolate direct contact between different fluorescent material cores, reduce chemical reactions and unfavorable energy transfer, and further suppress concentration quenching.

[0032] Typically, a single UV light converter is insufficient to achieve both high-efficiency UV absorption and high-efficiency fluorescence performance. For example, while a single second UV light converter exhibits high UV absorption and light conversion performance, its maximum emission peak is around 420 nm, which is not the optimal response wavelength for crystalline silicon cells. A single third UV light converter has weak UV absorption capabilities, and a single first UV light converter has a large Stokes shift, resulting in low light conversion efficiency. Therefore, the three UV light converters described in this application are used in combination to achieve functional complementarity, thereby improving the light utilization rate of photovoltaic modules and enabling the formulation of more colors, thus meeting the aesthetic design requirements of photovoltaic modules.

[0033] In one embodiment of this application, when the light-converting film is a purple light-converting film, the UV light converter is a combination of a first UV light converter and a second UV light converter, and the mass ratio of the first UV light converter to the second UV light converter is 66:34; preferably, when the light-converting film is a yellow light-converting film, the UV light converter is a combination of a first UV light converter and a third UV light converter, and the mass ratio of the first UV light converter to the third UV light converter is 50:50; preferably, when the light-converting film is a cyan light-converting film, the UV light converter is a combination of a third UV light converter and a second UV light converter, and the mass ratio of the third UV light converter to the second UV light converter is 40:60.

[0034] When the light-converting film is a purple light-converting film, it is preferable that the first UV light converter and the second UV light converter are in the above-mentioned mass ratio. This helps to finely control the hue of the purple light emitted by the light-converting film and also helps to reduce spectral mismatch loss, thereby improving the light conversion efficiency of the light-converting film and the performance of the component.

[0035] When the light-converting film is yellow, it is preferable that the mass ratio of the first UV light converter to the third UV light converter is within the above range. This helps to finely control the hue of the yellow light emitted by the light-converting film and also helps the spectral output of the light-converting film to better match the absorption spectrum of the crystalline silicon cell, reducing spectral mismatch loss and thus improving the overall photoelectric conversion efficiency of the photovoltaic module.

[0036] When the light-converting film is a cyan light-converting film, it is preferable that the third UV light converter and the second UV light converter are in the above mass ratio. This helps to finely control the cyan hue of the light-converting film, while also helping to effectively supplement the spectral response region of the crystalline silicon cell, reducing direct irradiation of ultraviolet light, and increasing the absorption of visible light, thereby improving the power output and energy conversion efficiency of the cell module.

[0037] In one embodiment of this application, when the light-converting film is a blue-purple light-converting film, the UV light converter is a combination of a first UV light converter, a second UV light converter, and a third UV light converter, with a mass ratio of 10:80:10; preferably, when the light-converting film is a cyan-blue light-converting film, the UV light converter is a combination of a first UV light converter, a second UV light converter, and a third UV light converter, with a mass ratio of 25:40:35; preferably, when the light-converting film is a yellow-green light-converting film, the UV light converter is a combination of a first UV light converter, a second UV light converter, and a third UV light converter, with a mass ratio of 40:20:40.

[0038] When the light-converting film is a blue-violet light-converting film, it is preferable that the first UV light converter, the second UV light converter, and the third UV light converter are in the above-mentioned mass ratio. This helps to finely control the hue of the blue-violet light emitted by the light-converting film, improving color accuracy. Simultaneously, it also helps to improve the photoelectric conversion efficiency and stability of photovoltaic modules.

[0039] When the light-converting film is a cyan-blue light-converting film, it is preferable that the first UV light converter, the second UV light converter, and the third UV light converter are in the above-mentioned mass ratio. This helps to finely control the cyan-blue hue of the final light emitted by the light-converting film. It also helps to further improve spectral complementarity, reduce spectral mismatch losses, and thus improve the photoelectric conversion efficiency of crystalline silicon solar cell modules.

[0040] When the light-converting film is a yellow-green light-converting film, it is preferable that the first UV light converter, the second UV light converter, and the third UV light converter are in the above-mentioned mass ratio. This helps to finely control the hue of the yellow-green light ultimately emitted by the light-converting film. It also helps to further improve spectral complementarity, reduce spectral mismatch loss, and thus improve the photoelectric conversion efficiency of crystalline silicon solar cell modules.

[0041] In one embodiment of this application, the transmittance of the light-converting film to ultraviolet light in the wavelength range of 280~380nm is 1~50%; and / or, the thickness of the light-converting film is 300~600μm.

[0042] The preferred light-converting film has a transmittance of ultraviolet light in the 280-380nm wavelength range within the aforementioned range. This helps the film absorb sufficient ultraviolet light for conversion while mitigating thermal relaxation and material damage caused by excessive absorption. The preferred thickness of the light-converting film is also within the aforementioned range, which helps improve the light conversion efficiency of the photovoltaic module while maintaining good mechanical strength and flexibility.

[0043] In order to improve the output power of photovoltaic modules and to produce more colors, in one embodiment of this application, the light-converting film further includes: a main crosslinking agent, a co-crosslinking agent, a silane coupling agent, a light stabilizer, and an antioxidant.

[0044] In one embodiment of this application, the light-converting film comprises, by weight, 100 parts of a base resin, 0.3 to 2 parts of a main crosslinking agent, 0.3 to 2 parts of a co-crosslinking agent, 0.1 to 2 parts of a silane coupling agent, 0.1 to 1.5 parts of a light stabilizer, and 0.1 to 2 parts of an antioxidant.

[0045] The addition of the aforementioned parts by weight of matrix resin helps to give the light-converting film sufficient structural stability and mechanical strength for effective bonding to the battery module during encapsulation. It also helps to regulate the properties of the light-converting film, such as transmittance and dielectric constant, giving it good light transmission performance and dielectric isolation effect, providing an ideal conversion environment for fluorescent materials. The addition of the aforementioned parts by weight of primary crosslinking agent helps to enhance the crosslinking reaction between matrix resin molecules, forming a dense network structure, thereby improving the cohesion and weather resistance of the light-converting film. It also helps to improve the adhesion strength between the light-converting film and the battery surface and other encapsulation materials (such as glass and backsheet), reducing air gaps and improving the sealing performance of the encapsulation, thereby enhancing the durability and power output stability of the photovoltaic module. The addition of the aforementioned parts by weight of co-crosslinking agent helps to assist the primary crosslinking agent, promoting the uniformity of the crosslinking reaction throughout the film layer, thereby improving the overall performance of the material. The addition of the aforementioned parts by weight of silane coupling agent helps improve the interfacial compatibility between the fluorescent material and the matrix resin, ensuring uniform dispersion of the fluorescent material in the film and thus improving light conversion efficiency. It also helps enhance the adhesion between the film and the solar cell and encapsulation materials, maintaining the structural integrity of the module during long-term use. The addition of the aforementioned parts by weight of light stabilizer not only helps absorb or block ultraviolet light, reducing photodegradation of the fluorescent material and matrix resin, thereby extending the film's lifespan, but also helps maintain the light conversion performance of the light-converting film. The addition of the aforementioned parts by weight of antioxidant helps reduce oxidative damage to the fluorescent material and matrix resin from atmospheric oxygen, maintaining the chemical stability and optical properties of the materials.

[0046] To further improve the overall performance of the light-converting film, in one embodiment of this application, the matrix resin is selected from any one or more of ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer, and ethylene-methyl methacrylate copolymer; and / or, the main crosslinking agent is selected from any one or more of dicumyl peroxide, benzoyl peroxide, amyl peroxide, tert-amyl peroxide 3,5,5-trimethylhexanoate, di-tert-butyl peroxide, tert-butyl isopropyl peroxide, dicyclohexyl peroxide, bis(2-phenylethoxy) peroxide, di(2-ethylhexyl) peroxide, bis(4-tert-butylcyclohexyl) peroxide, and tert-butyl tert-valerate peroxide; and / or, the silane coupling agent is selected from γ-aminopropyltriethoxysilane and γ-methacryloyloxypropyltrimethoxysilane. Alkane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, vinyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidyl etheroxypropyltrimethylsilane, 3-aminopropyltrimethylsilane; and / or, the light stabilizer is selected from 2-(2-hydroxyphenyl)-benzotriazole, a polymer of succinic acid and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol, N, N-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-phenylenediamide, 2,2,6,6-tetramethylpiperidinamine, 1,3-diphenylisobenzofuran, and 9,10-anthradiyl-bis(methylene)dimalonic acid; and / or, the antioxidant is selected from any one or more of hindered phenolic antioxidants, aromatic amine antioxidants, phosphite antioxidants, thioether antioxidants, and metal passivating antioxidants.

[0047] In another typical embodiment of this application, a photovoltaic module is provided, including an encapsulating film, which includes the light-converting film described above.

[0048] Photovoltaic modules including the aforementioned light-converting films have high photoelectric conversion efficiency, and the aforementioned light-converting films have different colors to meet the aesthetic design requirements of photovoltaic modules.

[0049] The beneficial effects of this application will be further illustrated below with reference to the embodiments.

[0050] Example 1

[0051] The raw materials of the light-converting film, by weight, are: 100 parts of the base resin ethylene-vinyl acetate copolymer, 0.5 parts of the main crosslinking agent benzoyl peroxide, 0.5 parts of the co-crosslinking agent triallyl isocyanurate, 0.3 parts of the silane coupling agent γ-aminopropyltriethoxysilane, 0.1 parts of the light stabilizer 2,2,6,6-tetramethylpiperidinamine, 0.1 parts of the antioxidant 2,6-di-tert-butyl-4-methylphenol, and a UV light converter. The areal concentration of the UV light converter is 0.8 g / m². 2 The UV light converter consists of a first UV light converter, a p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, and a second UV light converter, a benzotriazole-based fluorescent material. The combination of (R1 substituent is isobutyl, R2 substituent is tert-butyl) has a mass ratio of 66:34 for the first UV light converter and the second UV light converter. The maximum absorption peak of the first UV light converter is 375 nm, and the maximum emission peak of the first UV light converter is 607 nm. The maximum absorption peak of the second UV light converter is 365 nm, and the maximum absorption and emission peaks of the second UV light converter are 418 nm.

[0052] After mixing the above raw materials, they are added to an extruder. After being melted and plasticized by the extruder, they are extruded to the three rollers to be shaped into a film, resulting in a purple light-converting adhesive film with a thickness of 420μm.

[0053] Example 2

[0054] The difference from Example 1 is that the third UV light converter is modified cesium lead bromine quantum dots, which are cesium lead bromine quantum dots coated with silica (prepared according to the method of patent CN114686218B). The average particle size of the third UV light converter is 10 nm. The mass ratio of oxide shell to perovskite quantum dots is 1:1. The maximum absorption peak of the third UV light converter is 403 nm, and the maximum emission peak of the third UV light converter is 490 nm. The UV light converter is a combination of the first UV light converter, p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, and the third UV light converter, cesium lead bromine quantum dots. The mass ratio of the first UV light converter to the third UV light converter is 50:50, and a yellow light-converting film is finally obtained.

[0055] Example 3

[0056] The difference from Example 1 is that the second UV light converter is the benzotriazole fluorescent material in Example 1, the third UV light converter is the modified cesium lead bromine quantum dots in Example 2, the UV light converter is a combination of the third UV light converter and the second UV light converter, and the mass ratio of the third UV light converter to the second UV light converter is 40:60, finally obtaining a cyan light-converting film.

[0057] Example 4

[0058] The difference from Example 1 is that the first UV light converter is a ternary complex of p-chlorobenzoic acid-o-phenanthroline-europium, the second UV light converter is the benzotriazole fluorescent material in Example 1, and the third UV light converter is the modified cesium lead bromine quantum dots in Example 2. The UV light converter is a combination of the first, second, and third UV light converters, and the mass ratio of the first, second, and third UV light converters is 10:80:10, finally yielding a blue-violet light-converting film.

[0059] Example 5

[0060] The difference from Example 4 is that the mass ratio of the first UV light conversion agent, the second UV light conversion agent and the third UV light conversion agent is 25:40:35, and a cyan-blue light conversion film is finally obtained.

[0061] Example 6

[0062] The difference from Example 4 is that the mass ratio of the first UV light conversion agent, the second UV light conversion agent and the third UV light conversion agent is 40:20:40, and a yellow-green light conversion film is finally obtained.

[0063] Example 7

[0064] The difference from Example 4 is that, by weight, the raw materials of the light-converting film are: 100 parts of the matrix resin ethylene-vinyl acetate copolymer, 0.3 parts of the main crosslinking agent benzoyl peroxide, 0.3 parts of the co-crosslinking agent triallyl isocyanurate, 0.1 parts of the silane coupling agent γ-aminopropyltriethoxysilane, 0.1 parts of the light stabilizer 2,2,6,6-tetramethylpiperidinamine, 0.1 parts of the antioxidant 2,6-di-tert-butyl-4-methylphenol, and a UV light converter. The areal concentration of the UV light converter is 0.3 g / m². 2 The final product is a blue-purple light-converting film.

[0065] Example 8

[0066] The difference from Example 4 is that, by weight, the raw materials of the light-converting film are: 100 parts of the matrix resin ethylene-vinyl acetate copolymer, 2 parts of the main crosslinking agent benzoyl peroxide, 2 parts of the co-crosslinking agent triallyl isocyanurate, 2 parts of the silane coupling agent γ-aminopropyltriethoxysilane, 1.5 parts of the light stabilizer 2,2,6,6-tetramethylpiperidinamine, 2 parts of the antioxidant 2,6-di-tert-butyl-4-methylphenol, and a UV light converter. The areal concentration of the UV light converter is 2 g / m². 2 The final product is a blue-purple light-converting film.

[0067] Example 9

[0068] The difference from Example 4 is that the surface concentration of the UV light conversion agent is 1 g / m². 2 The final product is a blue-purple light-converting film.

[0069] Example 10

[0070] The difference from Example 4 is that the mass ratio of oxide shell to cesium lead bromine quantum dot material in the modified cesium lead bromine quantum dots is 2:1, and a blue-violet light-converting film is finally obtained.

[0071] Example 11

[0072] The difference from Example 4 is that the mass ratio of oxide shell to cesium lead bromine quantum dot material in the modified cesium lead bromine quantum dots is 0.1:1, and a blue-violet light-converting film is finally obtained.

[0073] Example 12

[0074] The difference from Example 4 is that the mass ratio of oxide shell to cesium lead bromine quantum dot material in the modified cesium lead bromine quantum dots is 3:1, and a blue-violet light-converting film is finally obtained.

[0075] Comparative Example 1

[0076] The difference from Example 1 is that the UV light converter is only the first UV light converter, p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, which ultimately yields a red light-converting film.

[0077] Comparative Example 2

[0078] The difference from Example 1 is that the UV light converter is only the second UV light converter, benzotriazole fluorescent material, which ultimately yields a blue light-converting film.

[0079] Comparative Example 3

[0080] The difference from Example 1 is that the UV light conversion agent is only the third UV light conversion agent modified cesium lead bromine quantum dots, and finally a green light conversion film is obtained.

[0081] Comparative Example 4

[0082] The difference from Example 1 is that the areal concentration of the UV light conversion agent in the light-converting film is 2.5 g / m². 2 Finally, a purple light-converting film was obtained.

[0083] Comparative Example 5

[0084] The difference from Example 3 is that the third UV light conversion agent is replaced with the light conversion agent of Example 4 in patent CN120647594A, which has a maximum absorption peak of 400nm and a maximum emission peak of 505nm, and finally a cyan light conversion film is obtained.

[0085] Comparative Example 6

[0086] According to the formulation of Example 4 in patent CN119752347A, a cyan light-converting film was finally obtained.

[0087] Test method:

[0088] Ultraviolet light transmittance test: GB / T 29848-2018;

[0089] L-value, A-value, and B-value testing: GB / T 29848-2018;

[0090] HJT module power testing: IEC-61215;

[0091] The test results are shown in Table 1.

[0092] Table 1

[0093]

[0094] As shown in Table 1, compared with the light-converting films of Comparative Examples 1 to 3 that use only a single UV light-converting agent, the embodiments of this application use at least two of the first, second, and third UV light-converting agents in combination. The emission peaks of the first, second, and third UV light-converting agents do not fall within the absorption peak range of each other, and the emission peaks are separated from each other. In particular, the first UV light-converting agent is a rare-earth fluorescent material, which is a typical light-converting material with a wide absorption peak range but a very narrow emission peak range. The second UV light-converting agent is an organic light-converting agent with relatively wide absorption and emission peaks. The third UV light-converting agent is a quantum dot with a relatively narrow absorption peak range. This effectively avoids the "reabsorption" phenomenon, maximizes the utilization rate of light, and results in high initial power and low power loss of the component.

[0095] Based on the degradation results of UV aging of HJT modules, the light conversion film with a higher proportion of the second UV light conversion agent showed less power loss. This is mainly because the second UV light conversion agent has a smaller Stokes shift and higher light conversion efficiency. In Comparative Example 5, both the green and blue light conversion agents are organic materials with wide absorption and emission peak ranges. Therefore, when most of the emission peaks of the second UV light conversion agent are absorbed by the third UV light conversion agent, a severe "reabsorption" phenomenon occurs, resulting in low photon energy utilization and thus lower photovoltaic module power.

[0096] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0097] The light-converting film of this application combines at least two of the three UV light-converting agents with different maximum emission peak ranges and adjusts their proportions to achieve "precise trimming" and "on-demand conversion" of the solar spectrum. This maximizes the conversion of low-utilization light, such as ultraviolet light, into specific wavelengths of light most sensitive to the target photovoltaic cell, significantly improving the output power of the photovoltaic module. Simultaneously, it allows for the formulation of more colors, thus meeting the diverse application scenarios of photovoltaic modules. Because the emission spectrum of one UV light-converting agent overlaps with the absorption spectrum of another, a "reabsorption" phenomenon occurs, causing severe photon loss. However, the emission peaks of the three UV light-converting agents in this application are separated from their absorption peaks, minimizing the spectral overlap region and greatly reducing reabsorption, thereby reducing photon loss. Typically, a single UV light-converting agent is insufficient to achieve both high-efficiency ultraviolet absorption and high-efficiency fluorescence performance. The three UV light-converting agents in this application, used in combination and with the surface concentration controlled within the aforementioned range, achieve functional complementarity, thereby improving the light utilization rate of the photovoltaic module and allowing for the formulation of more colors, thus meeting the aesthetic design requirements of photovoltaic modules.

[0098] The above are merely embodiments of the present invention and are not intended to limit the invention. Those skilled in the art will recognize that the present invention can have various modifications and variations. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A light-converting adhesive film, characterized in that, The light-converting film comprises: a matrix resin and a UV light-converting agent; The areal concentration of the UV light conversion agent in the light-converting film is 0.3~2 g / m². 2 The UV light conversion agent includes at least two of a first UV light conversion agent, a second UV light conversion agent, and a third UV light conversion agent. The first UV light converter has a maximum absorption peak of 370~380nm and a maximum emission peak of 605~615nm; the second UV light converter has a maximum absorption peak of 350~370nm and a maximum emission peak of 415~425nm; and the third UV light converter has a maximum absorption peak of 370~405nm and a maximum emission peak of 485~505nm.

2. The light-converting adhesive film according to claim 1, characterized in that, The first UV light converter includes rare earth fluorescent materials; preferably, the rare earth fluorescent materials are europium rare earth fluorescent materials; the europium rare earth fluorescent materials are selected from any one or more of the following: p-chlorobenzoic acid-o-phenanthroline-europium ternary complex, p-hydroxybenzoic acid-o-phenanthroline-europium ternary complex, p-aminobenzoic acid-o-phenanthroline-europium ternary complex, benzoic acid-o-phenanthroline-europium ternary complex, 2-thiophenecarboxyltrifluoroacetone-o-phenanthroline-europium ternary complex, and dibenzoyl-o-phenanthroline-europium ternary complex.

3. The light-converting adhesive film according to claim 1 or 2, characterized in that, The second UV light converter includes a benzotriazole fluorescent material; the general structural formula of the benzotriazole fluorescent material is as follows: , Wherein, R substituent is Furthermore, the benzotriazole fluorescent material has at least one R substituent at positions 4 and 7, and the benzotriazole derivative has at least one R substituent at positions 5 and 6; R1 and R2 are each independently selected from H, substituted or unsubstituted C1~C1. 20 The alkyl group, at least one methylene group, is substituted with -COO- or -O- at C3~C4. 20 Alkyl, substituted or unsubstituted C2~C 20 Any one of the alkenyl groups; when there are substituents, the substituents are selected from any one or more of methyl, ethyl, propyl, butyl, trifluoromethyl, and nitro.

4. The light-converting adhesive film according to any one of claims 1 to 3, characterized in that, The third UV light conversion agent includes modified perovskite quantum dots, which comprise perovskite quantum dot material and an oxide shell coating the outer surface of the perovskite quantum dot material. The oxide shell material is silicon dioxide and / or zinc oxide. Preferably, the perovskite quantum dot material is cesium lead bromide perovskite quantum dots and / or cesium lead chloride perovskite quantum dots.

5. The light-converting adhesive film according to claim 4, characterized in that, The particle size of the third UV light converter is ≤10nm; and / or, the mass ratio of the oxide shell to the perovskite quantum dot material in the modified perovskite quantum dots is 0.1~2:

1.

6. The light-converting adhesive film according to any one of claims 1 to 5, characterized in that, The transmittance of the light-converting film to ultraviolet light in the wavelength range of 280~380nm is 1~50%; and / or, the thickness of the light-converting film is 300~600μm.

7. The light-converting adhesive film according to any one of claims 1 to 6, characterized in that, The light-converting film also includes: a primary crosslinking agent, a secondary crosslinking agent, a silane coupling agent, a light stabilizer, and an antioxidant.

8. The light-converting adhesive film according to claim 7, characterized in that, By weight, the light-converting film comprises: 100 parts of the matrix resin, 0.3 to 2 parts of the main crosslinking agent, 0.3 to 2 parts of the co-crosslinking agent, 0.1 to 2 parts of the silane coupling agent, 0.1 to 1.5 parts of the light stabilizer, and 0.1 to 2 parts of the antioxidant.

9. The light-converting adhesive film according to claim 8, characterized in that, The matrix resin is selected from any one or more of ethylene-vinyl acetate copolymer, ethylene-propylene copolymer, ethylene-butene copolymer, ethylene-hexene copolymer, ethylene-octene copolymer and ethylene-methyl methacrylate copolymer; And / or, the main crosslinking agent is selected from any one or more of dicumyl peroxide, benzoyl peroxide, amyl acetate peroxide, tert-amyl peroxide 3,5,5-trimethylhexanoate, di-tert-butyl peroxide, tert-butyl isopropyl peroxide carbonate, dicyclohexyl peroxide carbonate, bis(2-phenylethoxy) peroxide carbonate, di(2-ethylhexyl) peroxide carbonate, bis(4-tert-butylcyclohexyl) peroxide carbonate, and tert-butyl tert-valerate peroxide. And / or, the co-crosslinking agent is selected from at least one of 1,3,5-triallyl cyanurate, trimethylolpropane triacrylate, triallyl isocyanurate, and polytriallyl isocyanurate. And / or, the silane coupling agent is selected from any one or more of γ-aminopropyltriethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, vinyltrimethoxysilane, N-(β-aminoethyl)-γ-aminopropyltrimethoxysilane, γ-glycidoxypropyltrimethylsilane, and 3-aminopropyltrimethylsilane; And / or, the light stabilizer is selected from any one or more of 2-(2-hydroxyphenyl)-benzotriazole, a polymer of succinic acid and 4-hydroxy-2,2,6,6-tetramethyl-1-piperidinol, N,N-bis(2,2,6,6-tetramethyl-4-piperidinyl)-1,3-phenylenediamide, 2,2,6,6-tetramethylpiperidinamine, 1,3-diphenylisobenzofuran, and 9,10-anthratridiyl-bis(methylene)dimalonic acid; And / or, the antioxidant is selected from any one or more of hindered phenolic antioxidants, aromatic amine antioxidants, phosphite antioxidants, thioether antioxidants, and metal passivating antioxidants.

10. A photovoltaic module, comprising an encapsulating film, characterized in that, The encapsulating film includes the light-converting film according to any one of claims 1 to 9.

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