Black high-reflection infrared integrated packaging material and preparation method thereof

Abstract

The invention relates to the technical field of photovoltaic packaging materials, and discloses a black high-reflection infrared integrated packaging material and a preparation method thereof, and the black high-reflection infrared integrated packaging material comprises a bonding packaging layer, a light management layer, a mechanical transition layer and an insulating supporting layer which are arranged from top to bottom; all the layers are subjected to integrated melting and co-extrusion to obtain the packaging material; the first melting point of the bonding packaging layer is 70-100 DEG C, the second melting point of the bonding packaging layer is 110-130 DEG C, and the content of the cross-linked gel after irradiation is 5-30%; the melting point of the light management layer is 70-130 DEG C, the light management layer comprises a perylene black surface layer and a white light reflecting layer which are sequentially arranged, the visible light absorptivity of the perylene black surface layer is larger than or equal to 90%, and the infrared light transmittance of the perylene black surface layer is larger than or equal to 50%; the melting point of the mechanical transition layer is 90-130 DEG C; and the melting point of the insulating support layer is 120-180 DEG C. According to the invention, the high transmittance of infrared light is maintained while the deep black appearance is realized, the secondary absorption of the infrared light can be realized, and the overall efficiency of the assembly is improved.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic packaging materials, and in particular to a black highly infrared-reflective integrated packaging material and a preparation method thereof. Background Art

[0002] Black photovoltaic modules have a unique appeal in the market due to their deep black appearance and visual consistency, eliminating the visual separation of traditional silver, white and transparent parts. They are mainly used in high-end application markets that pursue a balance between aesthetics and performance, such as meeting consumers' demand for high-end residential design, or being used in building-integrated photovoltaics (BIPV) to form a good integration with the building's exterior walls or roofs. In addition, since all electrodes are hidden on the back of the cell, the front of the module is not blocked by grid lines, and the front of the cell is fully exposed to the sun, maximizing the absorption of light energy. When combined with a black module, there is no need to modify the cell surface to maintain a deep visual black, thus achieving a perfect combination of high efficiency and appearance design.

[0003] The existing technology enables photovoltaic modules to achieve a black appearance mainly through the following solutions: black backplane, black grid glass or black film. The black backplane can enhance the deep black appearance of the module, optimize UV ​​absorption, increase the ability to resist UV aging, and improve the weather resistance of the module. It is particularly suitable for the encapsulation of double-sided back-contact cells. Black grid glass is designed with a black grid or coating inside the front glass. Combined with the back-contact cell, it reduces the difference between cells, makes the module more integrated, and can further unify the visual effect of the module surface. The black film simply and effectively realizes the black module design by covering the gap area, while increasing the reflection utilization rate of light and further improving the visual consistency.

[0004] However, the above solution has the following problems: (1) Thermal accumulation effect: Black materials have a strong ability to absorb light. Although they can achieve a deep black appearance within the visible light range, they also lead to higher heat accumulation, with an overall efficiency loss of about 2-5%, which is particularly significant under high irradiation and high temperature environments. The main manifestation is that the black backplane will absorb a large amount of solar radiation, causing the overall temperature of the component to rise, resulting in a decrease in the efficiency of the photovoltaic cell (usually the efficiency decreases by about 0.4-0.5% for every 1°C increase in temperature). The black film will increase heat absorption, accelerate heat accumulation, and further amplify the temperature sensitivity problem of the back contact cell.

[0005] (2) Loss of optical performance: Although the high light absorption of black materials can improve the consistency of appearance, it may also affect the photoelectric conversion efficiency of photovoltaic modules. The optical loss is about 1-3%, especially in the gap and edge areas of the modules. The main manifestation is that the grid design of the black grid glass will block or absorb part of the incident light, reducing the amount of light entering the cell. The black film will reduce the amount of light transmitted by covering the gap area. If there is no reflective design, the light utilization rate will be directly reduced.

[0006] (3) Material aging and durability issues: Pigments and additives in black materials are prone to aging and performance degradation under long-term exposure to ultraviolet rays, high temperature, high humidity and other conditions, which shortens the material life, resulting in reduced reliability of component packaging and increased maintenance and replacement costs. The main manifestation is that the pigments in the black backplane may fade or decompose at high temperatures, resulting in reduced backplane performance. The ultraviolet absorption capacity weakens over time, affecting the protective performance of the backplane. The black coating in the black grid glass may fall off or change color in a long-term outdoor environment. The black film will be affected by thermal aging and UV degradation, which may cause the film's bonding performance to deteriorate and increase the risk of component failure.

[0007] (4) Increased process complexity and cost: The introduction of black materials usually requires more complex manufacturing processes and higher-cost raw materials, which increases the overall production cost, especially the increased investment in high-precision manufacturing equipment. This is mainly reflected in the fact that the grid design of the black grid glass requires precise alignment of the battery cells. Any slight deviation may cause efficiency loss and increase the difficulty of the process. The black backplane and film require additional ultraviolet absorbers, antioxidants and thermal stabilizers to ensure a long life, but this increases material and processing costs. Summary of the invention

[0008] In order to solve the above technical problems, the present invention provides a black high-reflective infrared integrated packaging material and a preparation method thereof, which integrates the black appearance, optical transmittance and infrared high-reflective function into an integrated packaging material, achieving a deep black appearance while maintaining a high transmittance of infrared light, achieving secondary absorption of infrared light, improving the overall efficiency of the component, effectively reducing heat accumulation, and reducing component efficiency attenuation at high temperatures. In addition, the co-extrusion molding process directly realizes a multi-layer structure without the need to introduce a separate black film or backplane or reflective coating, reducing materials and processes, and reducing complexity and cost.

[0009] The purpose of the present invention is achieved through the following technical solutions: In the first aspect, the present invention provides a black highly infrared reflective integrated packaging material, comprising an adhesive packaging layer, a light management layer, a mechanical transition layer and an insulating support layer arranged from top to bottom; the packaging material is obtained by integrated melt co-extrusion of each layer; the matrix resin used in each layer includes one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene, and vinyl acetate; the first melting point of the adhesive packaging layer is 70-100°C, the second melting point is 110-130°C, and the cross-linked gel content after irradiation is 5-30%; the melting point of the light management layer is 70-130°C, the light management layer comprises a perylene black surface layer and a white light reflecting layer arranged in sequence from top to bottom, the visible light absorption rate of the perylene black surface layer is ≥90%, and the infrared light transmittance is ≥50%; the melting point of the mechanical transition layer is 90-130°C; the melting point of the insulating support layer is 120-180°C.

[0010] The integrated packaging material in the present invention can replace the combination of traditional packaging film and photovoltaic backplane, and meet the mechanical properties of photovoltaic modules at the working temperature by physically winding polymer segments (resin system). Different types of materials can be integrated and melt-coextruded, which shortens the process time of module lamination, improves module reliability, and realizes the characteristics of multi-functional compatibility.

[0011] Among them, the bonding encapsulation layer plays a good bonding performance. The light management layer includes a perylene black surface layer and a white light reflection layer. The perylene black surface layer can absorb visible light and transmit infrared light, achieving a deep black appearance while maintaining a high transmittance of infrared light, reducing heat accumulation, avoiding excessive heating caused by traditional black materials, and avoiding a significant decrease in efficiency. The white light reflection layer contains a light reflection additive, which reflects the transmitted infrared light back to the battery cell, achieving secondary absorption of infrared light and improving the overall efficiency of the component. Therefore, the light management layer can increase the utilization rate of infrared light by photovoltaic modules through the design of black infrared transmission and white light reflection, improve the overall power, effectively reduce heat accumulation, alleviate the impact of temperature on battery efficiency, and reduce the efficiency attenuation of modules at high temperatures. The mechanical transition layer acts as a buffer layer to reduce the impact of thermal expansion and contraction on the encapsulation layer and battery cells, and ensure the dimensional stability of the material in high and low temperature environments. The insulating skeleton layer provides good supporting mechanical effects, has extremely low oxygen and water vapor permeability, protects the battery cells from environmental erosion, and improves the long-term weather resistance and service life of the module. The multi-layer composite design can effectively reduce the penetration of external water vapor and oxygen, slow down the aging of internal components, and protect internal battery cells and circuits from corrosion.

[0012] The black appearance, optical transmittance and infrared high reflective function are integrated into an integrated packaging material. The co-extrusion molding process directly realizes the multi-layer structure without the need to introduce a separate black film or backplane or reflective coating, reducing materials and processes, and reducing complexity and cost.

[0013] Preferably, the light management layer has a gap structure, which includes black high-reflective infrared bands arranged in gaps, the black high-reflective infrared bands correspond to the gaps of the battery strings, and the gaps of the black high-reflective infrared bands correspond to the battery strings. The width of the black high-reflective infrared bands is 0.5-5mm, and the gap width between adjacent black high-reflective infrared bands is 156-210mm. The black high-reflective infrared bands include a perylene black surface layer and a white light reflection layer arranged in sequence.

[0014] Preferably, the base resin in the resin system used in each layer includes one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene, and vinyl acetate, the mass fraction of alpha olefin in the copolymer is controlled at 5-20wt%, and the proportion of vinyl acetate as a comonomer is controlled at 18-40wt%.

[0015] Preferably, the base resin in the resin system used in each layer further includes a polar modified resin, which is one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene, and vinyl acetate modified by polar groups. The polar groups include one or more of silane groups, siloxy groups, epoxy groups, maleic anhydride groups, and isocyanate groups.

[0016] Preferably, the resin in the resin system has a melt index of 2-20 g / 10min and a density of 0.850-0.950 g / cm 3 , number average molecular weight is 50,000-250,000, and molecular weight distribution is 2.8-20.

[0017] Preferably, the resin system used for the bonding encapsulation layer is 5-30% low melting point resin, 70-90% high melting point resin, and 3-5% polar modified resin, calculated by mass percentage.

[0018] Preferably, the resin system used for the perylene black surface layer in the photomanagement layer is one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene and vinyl acetate, calculated by mass percentage.

[0019] Preferably, the resin system used in the white light reflecting layer in the light management layer is 5-40% low melting point resin, 60-95% high melting point resin, and 3-5% polar modified resin, calculated by mass percentage.

[0020] Preferably, the low melting point resin has a melting point of 70-100° C. and a melt index of 11-20 g / 10 min; the high melting point resin has a melting point of 110-130° C. and a melt index of 3-10 g / 10 min.

[0021] The light management layer adopts a resin system similar to the bonding encapsulation layer. The melting point of each layer is mainly determined by the melting point of the selected resin system. The white light reflection layer and the bonding encapsulation layer in the light management layer have two melting points, the first melting point is 70-100°C, and the second melting point is 110-130°C.

[0022] Preferably, the melting point of the resin system used in the mechanical transition layer is 90-130° C., including polar modified resin.

[0023] Preferably, the melting point of the resin system used in the insulating support layer is 140-180° C. In terms of mass percentage, the resin system comprises 90-95% of a resin having a melting point of 140-180° C. and a melt index of 2-12 g / 10 min.

[0024] Preferably, the bonding encapsulation layer includes the following components, based on the mass ratio of the resin system of this layer: 0.5-3% of radiation cross-linking agent, 0.5-1% of UV stabilizer, 0.2-0.4% of heat stabilizer, 0.3-1% of coupling agent and 4-6% of polar group grafted masterbatch.

[0025] Preferably, the perylene black surface layer comprises the following components, based on the mass ratio of the resin system of the layer: 0.1-3% perylene black auxiliary agent and 0.5-2% dispersant.

[0026] Preferably, the white light reflecting layer comprises the following components, based on the mass ratio of the base resin of the layer: 3-20% of light reflecting agent, 12-20% of polar group grafted masterbatch, 3-10% of dispersant, 0.5-1% of UV stabilizer and 0.2-0.4% of heat stabilizer.

[0027] Preferably, the mechanical transition layer includes the following components, calculated by mass ratio to the resin system of the layer: 0.5-3% of radiation co-crosslinking agent, 0.5-1% of UV stabilizer, 0.2-0.4% of heat stabilizer, 0.5-1% of coupling agent and 0-1% of processing aid. There is no special regulation on the degree of radiation crosslinking of the mechanical transition layer.

[0028] Preferably, the insulating support layer comprises the following components, calculated by weight ratio to the resin system of the layer: 0.5-2% of a heat stabilizer, 0.8-1.5% of a UV stabilizer and 0.5-10% of a processing aid.

[0029] Preferably, the thickness of the bonding encapsulation layer is 100-300 μm; the thickness of the perylene black surface layer in the light management layer is 10-20 μm, the thickness of the white light reflection layer is 80-100 μm; the thickness of the mechanical transition layer is 20-80 μm; and the thickness of the insulating support layer is 200-300 μm.

[0030] Preferably, the perylene black additive includes one or more of black pigments (such as carbon black, perylene black), specifically including one or more of BASF Paliogen® Black, BASF Lumogen® Black, Perylene Black N3300, PeryleneTetracarboxylic Diimide (PTCDI), N,N'-Bis(phenyl) Perylene-3,4,9,10-Tetracarboxylic Diimide, Phenyl-Perylene-3,4-Dicarboximide, Perylene Monoimide, Perylene Tetracarboxylic Dianhydride (PTCDA), Poly(Perylene Imide), Poly(Perylene-Tetraimide), Perylene-Graphene Hybrid, Perylene-Silica Composite, Solvent, and Pigment Black 32.

[0031] Preferably, the light reflecting agent comprises one or more of titanium dioxide, barium sulfate, aluminum oxide and hollow glass microspheres; the reflectivity of the light reflecting agent is greater than 90%; and the particle size distribution is not greater than 1.5 μm.

[0032] The dispersant includes one or more of polyethylene wax, polypropylene wax and calcium stearate.

[0033] Preferably, the radiation cross-linking aid comprises a multifunctional unsaturated monomer, including one or more of multifunctional acrylate, olefin and isocyanate compounds.

[0034] The radiation auxiliary cross-linking agent can generate free radicals under radiation conditions to form cross-links.

[0035] Acrylate compounds: Ethylene glycol dimethacrylate (EGDMA), trimethylolpropane triacrylate (TMPTA), hexanediol diacrylate (HDDA), hexanediol diacrylate (HDDA), pentaerythritol tetraacrylate (PETA, Pentaerythritol Tetraacrylate), pentaerythritol tetramethacrylate (PETMA, Pentaerythritol Tetramethacrylate), triphenylmethane triacrylate (TPMTA, Triphenylmethane Triacrylate), bisphenol A diglycidyl ether diacrylate (Bisphenol ADiacrylate), dipentaerythritol hexaacrylate, polypentaerythritol multiacrylate (DPHA), triethoxysilane acrylate (Acryloxypropyltriethoxysilane, APTES), allyl acrylate, allyl methacrylate, diallyl maleate, diallyl phthalate, allyl acrylate, allyl methacrylate, trimethylolpropane trimethacrylate, pentaerythritol triacrylate, ethoxylated glycerol triacrylate, tetramethylolmethane triacrylate, ethoxylated pentaerythritol tetraacrylate, dimethylolpropane tetraacrylate, trimethylolethane trimethacrylate, tetramethylolmethane tetraacrylate, ditrimethylolpropane tetraacrylate, tetramethylolmethane tetramethacrylate, ditrimethylolpropane tetramethacrylate, dipentaerythritol polyacrylate, dipentaerythritol hexaacrylate, dipentaerythritol polymethacrylate, dipentaerythritol hexamethacrylate.

[0036] Olefin compounds: divinylbenzene, di-isopropenylbenzene, diallyl phthalate.

[0037] Isocyanate compounds: trimethallyl isocyanate, triallyl isocyanurate, triallyl cyanurate.

[0038] Preferably, the coupling agent includes one or more of a silane coupling agent, a titanate coupling agent, an isocyanate coupling agent, a phosphorus-containing coupling agent, an epoxy resin coupling agent, a surfactant coupling agent, and an anhydride-modified resin.

[0039] Silane coupling agent: γ-glycidoxypropyltrimethoxysilane (KH-560), vinyltriethoxysilane (VTES), aminopropyltriethoxysilane (KH-550), mercaptopropyltrimethoxysilane (KH-580), 3-glycidoxypropyltrimethoxysilane (3-Glycidoxypropyltrimethoxysilane).

[0040] Isocyanate coupling agent: triisocyanate (such as HDI-Trimer).

[0041] Titanate coupling agent: isopropyl tri(dioctyl phosphate) titanate, tetraisopropyl titanate, di(acetylacetonate) diisopropyl titanate.

[0042] Phosphorus-containing coupling agents: phosphate esters (such as diethylhexyl phosphate), phosphate acrylates (such as ethylene glycol methacrylate phosphate).

[0043] Surfactant coupling agent: quaternary ammonium salt surfactant, block copolymer surface modifier, fluorinated silane (such as hexafluoropropane trifluoroethoxysilane), nanoparticle composite modifier (such as surface functionalization of nano-silica or alumina (silane or phosphoric acid modification)).

[0044] Anhydride modified resin: maleic anhydride grafted polyolefin (POE-g-MAH), methacrylic acid grafted polyolefin (POE-g-MAA).

[0045] Preferably, the UV stabilizer includes hindered amine light stabilizer HALS (Tinuvin 770, Tinuvin 622, Chimassorb 944), benzotriazole UV absorber (Tinuvin 234, Tinuvin 326, Tinuvin 327, Tinuvin 328), and mixed light stabilizer (Tinuvin 123, Tinuvin 329).

[0046] Preferably, the heat stabilizer includes one or more of hindered phenol antioxidants (Irganox 1010, Irganox 1076), phosphite antioxidants (Irgafos 168, Ultranox 626), thioester antioxidants (DSTDP, DLTDP), hindered amines (Tinuvin 770, Chimassorb 944), metal passivators (Irgacor 1520, Naugard XL-1), and nano additives (ZnO, TiO2).

[0047] Preferably, the polar group grafted masterbatch comprises a masterbatch made of a resin grafted with a silane group, a siloxy group, an epoxy group, a maleic anhydride group or an isocyanate group. The resin comprises one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene and vinyl acetate.

[0048] Preferably, the processing aid includes one or more of a dispersant, a compatibilizer and an optical modifier.

[0049] In the second aspect, the present invention also provides a method for preparing a black, highly infrared-reflective, integrated packaging material, comprising the following steps: mixing the raw material components of each layer separately, and then melt-extruding them through multi-layer co-extrusion, the melt extrusion temperature of the bonding packaging layer is 180-200°C, the melt extrusion temperature of the perylene black surface layer in the light management layer is 180-190°C, the melt extrusion temperature of the white light reflecting layer in the light management layer is 200-220°C, the melt extrusion temperature of the mechanical transition layer is 190-220°C, and the melt extrusion temperature of the insulating support layer is 200-230°C; after extrusion, the cast film is cooled, and the black, highly infrared-reflective, integrated packaging material is obtained by irradiation pre-crosslinking and post-treatment.

[0050] Preferably, during casting cooling, the temperature of the cooling roller is 20-30°C.

[0051] Preferably, the film after casting and cooling is subjected to a baking heat treatment, with a baking temperature of ≥70°C and a time of ≥30s to eliminate processing thermal stress, and then irradiated for pre-crosslinking.

[0052] Preferably, the radiation pre-crosslinking is performed by electron beam irradiation, and the irradiation parameters are 150-500kev and 30-60kgy.

[0053] Preferably, the post-processing includes pulling and stretching, winding and reeling.

[0054] The film is stretched to control the thickness and mechanical properties.

[0055] Preferably, an antistatic coating may be applied online during post-treatment.

[0056] Compared with the prior art, the present invention has the following beneficial effects: (1) The light management layer includes a perylene black surface layer and a white light reflection layer. While achieving a deep black appearance, it maintains a high transmittance to infrared light, reduces heat accumulation, and is able to reflect the transmitted infrared light back to the cell to achieve secondary absorption of infrared light, thereby improving the overall efficiency of the component.

[0057] (2) The multi-layer composite design can ensure the bonding performance and mechanical properties, and effectively reduce the penetration of external water vapor and oxygen, slow down the aging of internal components, and protect the internal battery cells and circuits from corrosion.

[0058] (3) The black appearance, optical transmittance and infrared high reflectivity functions are integrated into an integrated packaging material. The co-extrusion molding process directly realizes a multi-layer structure without the need to introduce a separate black film or backplane or reflective coating, thereby reducing materials and processes, and reducing complexity and cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1This is a schematic structural diagram of the black, highly infrared-reflective integrated packaging material in Example 1 of the present invention.

[0060] Figure 2 This is a schematic diagram of the structure of the black highly infrared reflective integrated packaging material in Example 5 of the present invention.

[0061] The figures are marked as follows: 1. bonding packaging layer; 2. optical management layer; 3. mechanical transition layer; 4. insulating support layer. DETAILED DESCRIPTION

[0062] The technical solution of the present invention is described below with specific embodiments, but the protection scope of the present invention is not limited thereto.

[0063] Bonding encapsulation layer Ⅰ The raw material components of the bonding encapsulation layer I are shown in Table 1, and its first melting point is 90°C and its second melting point is 125°C.

[0064] Table 1

[0065] Bonding encapsulation layer Ⅱ The raw material components of the bonding encapsulation layer II are shown in Table 2, and the first melting point is 75°C and the second melting point is 120°C.

[0066] Table 2

[0067] Bonding encapsulation layer Ⅲ The raw material components of the bonding encapsulation layer III are shown in Table 3, and the first melting point is 85°C, and the second melting point is 115°C.

[0068] Table 3

[0069] Optical Management Layer I The raw material components of the light management layer I are shown in Table 4. The first melting point of the white light reflecting layer is 90°C, and the second melting point is 125°C.

[0070] Table 4

[0071] Optical Management Layer Ⅱ The raw material composition of the light management layer II is shown in Table 5. The first melting point of the white light reflecting layer is 75°C, and the second melting point is 120°C.

[0072] Table 5

[0073] Optical Management Layer Ⅲ The raw material composition of the light management layer III is shown in Table 6. The first melting point of the white light reflecting layer is 85°C, and the second melting point is 115°C.

[0074] Table 6

[0075] Mechanical transition layer I The raw material composition of the mechanical transition layer I is shown in Table 7, and its first melting point is 110°C and the second melting point is 130°C.

[0076] Table 7

[0077] Mechanical transition layer II The raw material composition of the mechanical transition layer II is shown in Table 8, and its melting point is 120°C.

[0078] Table 8

[0079] Mechanical transition layer III The raw material composition of the mechanical transition layer III is shown in Table 9, and its melting point is 110°C.

[0080] Table 9

[0081] Insulation support layer Ⅰ The raw material composition of the insulating support layer I is shown in Table 10, and its melting point is 165°C.

[0082] Table 10

[0083] Insulation support layer Ⅱ The raw material composition of the insulating support layer II is shown in Table 11, and its melting point is 145°C.

[0084] Table 11

[0085] Insulation support layer Ⅲ The raw material composition of the insulating support layer III is shown in Table 12, and its melting point is 160°C.

[0086] Table 12

[0087] Example 1 Black highly infrared reflective integrated packaging material: from inside to outside, it includes a 250μm adhesive packaging layer I (whose components are shown in Table 1), a 100μm light management layer I (whose components are shown in Table 4, including a 10μm perylene black surface layer and a 90μm white light reflection layer), a 50μm mechanical transition layer II (whose components are shown in Table 8) and a 200μm insulating support layer I (whose components are shown in Table 10).

[0088] The preparation of the above packaging material comprises the following steps: The raw material components of each layer are uniformly mixed by a high-speed mixer, and then multi-layer co-extrusion is adopted for melt extrusion. Four extruders are used for processing respectively, and the extruder temperatures are set as follows: the melt extrusion temperature of the bonding encapsulation layer is 180-200°C, the melt extrusion temperature of the perylene black surface layer in the light management layer is 180-190°C, the melt extrusion temperature of the white light reflection layer in the light management layer is 200-220°C, the melt extrusion temperature of the mechanical transition layer is 190-220°C, and the melt extrusion temperature of the insulating support layer is 200-230°C.

[0089] The five strands of molten materials are gathered to the co-extrusion die through a distributor to form a multi-layer flow channel structure. The molten materials are extruded through a wide die, and the resulting integrated film is cast onto a cooling roller at a temperature of 30°C and cooled to form. After that, the film is pre-crosslinked by electron beam irradiation with irradiation parameters of 200kev and 38kgy. After traction, stretching, winding, and reeling, the multi-layer film is reeled online and the thickness uniformity is tested, such as Figure 1 As shown, a black, highly infrared-reflective integrated packaging material is obtained, which includes, from top to bottom, a bonding packaging layer 1, a light management layer 2, a mechanical transition layer 3, and an insulating support layer 4.

[0090] Example 2 Black highly infrared reflective integrated packaging material: from inside to outside, it includes a 250μm adhesive packaging layer I (whose components are shown in Table 1), a 110μm light management layer III (whose components are shown in Table 6, including a 10μm perylene black surface layer and a 100μm white light reflection layer), a 30μm mechanical transition layer II (whose components are shown in Table 8) and a 230μm insulating support layer II (whose components are shown in Table 11).

[0091] The preparation steps and parameter settings of the above packaging materials are the same as those in Example 1.

[0092] Example 3 Black highly infrared reflective integrated packaging material: from inside to outside, it includes a 300μm adhesive packaging layer II (whose components are shown in Table 2), a 120μm light management layer II (whose components are shown in Table 4, including a 20μm perylene black surface layer and a 100μm white light reflection layer), a 50μm mechanical transition layer III (whose components are shown in Table 9) and a 200μm insulating support layer II (whose components are shown in Table 11).

[0093] The preparation steps and parameter settings of the above packaging materials are the same as those in Example 1.

[0094] Example 4 Black highly infrared reflective integrated packaging material: from inside to outside, it includes a 250μm adhesive packaging layer III (whose components are shown in Table 3), a 100μm light management layer III (whose components are shown in Table 6, including a 10μm perylene black surface layer and a 90μm white light reflection layer), a 50μm mechanical transition layer I (whose components are shown in Table 7) and a 200μm insulating support layer III (whose components are shown in Table 12).

[0095] The preparation steps and parameter settings of the above packaging materials are the same as those in Example 1.

[0096] Example 5 Black highly infrared reflective integrated packaging material: from inside to outside, it includes a 250μm adhesive packaging layer III (whose components are shown in Table 3), a 100μm light management layer III (having a gap structure, whose components are shown in Table 6, including a 10μm perylene black surface layer and a 90μm white light reflection layer), a 50μm mechanical transition layer I (whose components are shown in Table 7) and a 200μm insulating support layer III (whose components are shown in Table 12).

[0097] The preparation of the above packaging material comprises the following steps: The raw material components of each layer are uniformly mixed by a high-speed mixer, and then multi-layer co-extrusion is adopted for melt extrusion. Four extruders are used for processing respectively, and the extruder temperatures are set as follows: the melt extrusion temperature of the bonding encapsulation layer is 180-200°C, the melt extrusion temperature of the perylene black surface layer in the light management layer is 180-190°C, the melt extrusion temperature of the white light reflection layer in the light management layer is 200-220°C, the melt extrusion temperature of the mechanical transition layer is 190-220°C, and the melt extrusion temperature of the insulating support layer is 200-230°C.

[0098] The five streams of molten materials are converged to the co-extrusion die through a distributor to form a multi-layer flow channel structure. The molten material is extruded through a wide die, wherein the extrusion die of the light management layer (including two extrusion dies for the perylene black surface layer and the white light reflecting layer) includes a number of flow channels with fixed spacing positions. The reflective tape is extruded by controlling the gap positioning, and the extrusion position and width are controlled in the MD direction to form a gap reflective structure with regular gaps. The width of the reflective tape is 2mm, and the gap width between adjacent reflective tapes (the same as the battery width) is 180mm. The obtained integrated film is cast onto a cooling roller with a cooling roller temperature of 30°C and cooled to form; then it is pre-crosslinked by electron beam irradiation with irradiation parameters of 200kev and 38kgy; then it is pulled, stretched, wound, and rolled up, and the multi-layer film is rolled up online and the thickness uniformity is tested, such as Figure 2 As shown, a black high-infrared reflective integrated packaging material with a gap structure is obtained, which includes a bonding packaging layer 1, a light management layer 2, a mechanical transition layer 3, and an insulating support layer 4 from top to bottom.

[0099] Comparative Example 1 Packaging materials: from inside to outside, it includes a pre-cross-linked EVA layer (100μm; its raw materials include 2825 brand EVA particles and 0.5wt% of peroxide initiator, 0.3wt% of acrylic acid co-cross-linking agent, and 0.3wt% of silane coupling agent), an encapsulation EVA layer (300μm), and a commercially available black photovoltaic backplane (Crown BO-L3, with a total thickness of 360μm; the structure is a PET / PO film inner layer).

[0100] The above-mentioned layers of materials are laminated to obtain an integrated packaging material, and the lamination parameters are: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 10 minutes.

[0101] Table 13

[0102] Application Example 1 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Example 1 (the battery contact surface is the surface of the bonding packaging layer).

[0103] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 7 minutes.

[0104] Application Example 2 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Example 2 (the battery contact surface is the surface of the bonding packaging layer).

[0105] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 7 minutes.

[0106] Application Example 3 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Example 3 (the battery contact surface is the surface of the bonding packaging layer).

[0107] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 7 minutes.

[0108] Application Example 4 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Example 4 (the battery contact surface is the surface of the bonding packaging layer).

[0109] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 7 minutes.

[0110] Application Example 5 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Example 5 (the battery contact surface is the surface of the bonding packaging layer).

[0111] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 7 minutes.

[0112] Application Example 6 The structure of the photovoltaic module is: glass / EVA packaging film / TOPCon technology back-contact 0BB battery (wires connected in series on the battery with UV-curing glue) / packaging material obtained in Comparative Example 1 (the battery contact surface is the surface of the pre-cross-linked EVA layer).

[0113] The materials were assembled in the above order to obtain a photovoltaic module, and the photovoltaic module was laminated with the glass side facing downward. The lamination parameters were: temperature of 150° C., vacuuming for 5 minutes, pressure of -20 kPa, and pressure maintenance for 12 minutes.

[0114] Table 14

[0115] As shown in Table 13, the integrated photovoltaic module packaging materials with black high-reflective infrared structures prepared in Examples 1-5 can be cast and co-extruded at high temperatures, and have better overall performance than the traditional black backplane packaging materials prepared in Comparative Example 1. The present invention achieves a deep black appearance while maintaining a high transmittance to infrared light, reducing heat accumulation, and can reflect the transmitted infrared light back to the cell sheet to achieve secondary absorption of infrared light, thereby improving the overall efficiency of the module. At the same time, the multi-layer composite design can ensure the bonding performance and mechanical properties, effectively reduce the penetration of external water vapor and oxygen, slow down the aging rate of internal components, and achieve the characteristics of multi-functional compatibility.

[0116] As shown in Table 14, the packaging materials in Example 1 and Comparative Example 1 were assembled to obtain photovoltaic modules. From the data comparison between Application Example 1 and Application Example 6, it can be seen that the present invention can shorten the process time of module lamination, and the power output of the battery after packaging is also higher. The black high-reflective infrared layer in Example 5 has a gap structure, which can also achieve a high transmittance of infrared light while having a deep black appearance, and achieve secondary absorption of infrared light, and its application in battery packaging can also obtain a higher power output than Comparative Example 1.

[0117] The above are only preferred embodiments of the present invention, and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the specification of the present invention, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A black, highly infrared-reflective integrated packaging material, characterized in that: It includes a bonding packaging layer, a light management layer, a mechanical transition layer and an insulating support layer arranged from top to bottom; each layer is integrated and melt-coextruded to obtain a packaging material; the base resin used in each layer includes one or more of homopolymers and copolymers of ethylene, propylene, butene, hexene, octene and vinyl acetate; The first melting point of the bonding encapsulation layer is 70-100°C, the second melting point is 110-130°C, and the cross-linked gel content after irradiation is 5-30%; the melting point of the light management layer is 70-130°C, and the light management layer includes a perylene black surface layer and a white light reflecting layer arranged in sequence, and the visible light absorption rate of the perylene black surface layer is ≥90%, and the infrared light transmittance is ≥50%; the melting point of the mechanical transition layer is 90-130°C; the melting point of the insulating support layer is 120-180°C.

2. The black high infrared reflective integrated packaging material according to claim 1, characterized in that: The perylene black surface layer comprises the following components in terms of mass ratio to the matrix resin of the layer: 0.1-3% perylene black additive and 0.5-2% dispersant.

3. The black high infrared reflective integrated packaging material according to claim 2, characterized in that: Calculated by weight ratio to the matrix resin of the layer, the white light reflecting layer includes the following components: 3-20% of light reflecting aid, 12-20% of polar group grafted masterbatch, 3-10% of dispersant, 0.5-1% of UV stabilizer and 0.2-0.4% of heat stabilizer.

4. The black high infrared reflective integrated packaging material according to claim 3, characterized in that: The dispersant is one or more of polyethylene wax, calcium stearate and polypropylene wax; the light reflection auxiliary agent is one or more of titanium dioxide, hollow glass microspheres, aluminum oxide and barium sulfate.

5. The black high infrared reflective integrated packaging material according to claim 1, characterized in that: The bonding encapsulation layer comprises the following components, measured by mass ratio to the matrix resin of the layer: 0.5-3% of radiation co-crosslinking agent, 0.3-1% of coupling agent, 4-6% of polar group grafting masterbatch, 0.5-1% of UV stabilizer and 0.2-0.4% of heat stabilizer.

6. The black high-infrared reflective integrated packaging material according to claim 3 or 5, characterized in that: The polar group grafted masterbatch is a masterbatch prepared by a resin grafted with a silane group, an epoxy group, a siloxy group, an isocyanate group or a maleic anhydride group.

7. The black high infrared reflective integrated packaging material according to claim 1, characterized in that: Calculated by mass ratio to the matrix resin of the layer, the mechanical transition layer comprises the following components: 0.5-3% irradiation co-crosslinking agent, 0.5-1% coupling agent, 0.5-1% UV stabilizer, 0.2-0.4% heat stabilizer and 0-1% processing aid.

8. The black high infrared reflective integrated packaging material according to claim 1, characterized in that: Calculated by weight ratio to the matrix resin of the layer, the insulating support layer includes the following components: 0.8-1.5% of ultraviolet stabilizer, 0.5-2% of heat stabilizer and 0.5-10% of processing aid.

9. The black high infrared reflective integrated packaging material according to claim 5 or 7, characterized in that: The radiation auxiliary cross-linking agent includes one or more of the acrylic ester compounds containing multi-functional groups.

10. A method for preparing a black high-infrared reflective integrated packaging material as claimed in any one of claims 1 to 9, characterized in that: The method comprises the following steps: mixing the raw material components of each layer respectively, and then melt-extruding the raw material components through multi-layer co-extrusion, wherein the melt-extrusion temperature of the bonding packaging layer is 180-200°C, the melt-extrusion temperature of the perylene black surface layer in the light management layer is 180-190°C, the melt-extrusion temperature of the white light reflection layer in the light management layer is 200-220°C, the melt-extrusion temperature of the mechanical transition layer is 190-220°C, and the melt-extrusion temperature of the insulating support layer is 200-230°C; after extrusion, the raw material components are cast and cooled, and irradiated for pre-crosslinking and post-processed to obtain a black integrated packaging material with high infrared reflection.

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