Photovoltaic module insulation edge sealing adhesive tape and photovoltaic module packaging structure

Abstract

The invention provides a photovoltaic module insulation edge sealing adhesive tape and a photovoltaic module packaging structure, the photovoltaic module insulation edge sealing adhesive tape comprises an insulation layer and a bonding layer located on the surface of one side of the insulation layer, the relative temperature index RTI of the insulation layer is larger than or equal to 90 DEG C, the breakdown voltage of the insulation layer is larger than or equal to 8 KV, and the tracking index CTI of the insulation layer is larger than or equal to 175 V. According to the photovoltaic module insulation edge sealing adhesive tape and the photovoltaic module packaging structure provided by the invention, the insulation edge sealing adhesive tape can meet the performance requirement of the photovoltaic module on a reinforced insulation material, and the creepage distance can be prolonged after the insulation edge sealing adhesive tape covers at least one side surface of the photovoltaic module, so that the reliability of the photovoltaic module is improved, and the service life of the photovoltaic module is prolonged. On the premise that the area of the battery piece does not need to be reduced, the insulation safety requirement of the photovoltaic module packaging structure is improved, the filling density of the battery piece is increased, and therefore the photoelectric conversion efficiency of the photovoltaic module is improved.

Description

Technical Field

[0001] This invention relates to the field of insulating tape technology, and in particular to an insulating edge-sealing tape for photovoltaic modules and a photovoltaic module encapsulation structure. Background Technology

[0002] The photovoltaic (PV) module encapsulation structure, excluding the module frame and junction box, can be broadly divided from top to bottom into the front panel, encapsulation film layer, solar cells, and back panel. According to the IEC 61730 standard, the distances between PV module cells and the frame, and between the busbars and the frame, are limited by safety distances (creepage distances). Creepage distance refers to the shortest path between two conductive components or between a conductive component and a protective interface of equipment, measured along an insulating surface. To meet creepage distance requirements, the distance from the edge of the solar cell and busbar to the edge of the front or back panel material needs to be maintained at 11mm or more. This results in a reduction in the cell packing density inside the PV module, as some areas need to be reserved for safety distances, reducing the actual area of ​​solar cells participating in photoelectric conversion and affecting the PV module's conversion efficiency. Summary of the Invention

[0003] Based on the technical problems existing in the background art, the present invention proposes a photovoltaic module insulating edge sealing tape and a photovoltaic module encapsulation structure. The insulating edge sealing tape can effectively meet the performance requirements of photovoltaic modules for reinforced insulation materials. By wrapping the insulating edge sealing tape on at least one side of the photovoltaic module, the creepage distance can be extended. Without reducing the cell area, the insulation safety requirements of the photovoltaic module encapsulation structure are improved, thereby increasing the cell filling density and thus increasing the conversion efficiency of the photovoltaic module.

[0004] The present invention proposes a photovoltaic module insulating sealing tape, comprising an insulating layer and an adhesive layer located on one side surface of the insulating layer;

[0005] The insulation layer has a relative temperature index (RTI) greater than or equal to 90°C, a breakdown voltage greater than or equal to 8KV, and a tracking index (CTI) greater than or equal to 175V.

[0006] Preferably, the insulating layer is composed of at least one of polyolefins and their copolymers, polyurethane, glass fiber composites, polyimide, polyetherimide, or fluorinated polymers;

[0007] Preferably, the thickness of the insulating layer is 0.3-1 mm.

[0008] Preferably, the insulating layer is composed of a polyester layer and a modified epoxy resin insulating coating located on one side surface of the polyester layer.

[0009] Preferably, the modified epoxy resin insulating coating is an epoxy resin insulating coating containing organosilicon-modified nano boron nitride;

[0010] Preferably, the organosilicon-modified nano-boron nitride is obtained by coupling nano-boron nitride with a mercaptosilane coupling agent, followed by a "thiol-epoxy" click chemical reaction with a polyepoxy organosilicon.

[0011] Preferably, the mercaptosilane coupling agent is γ-mercaptopropyltrimethoxysilane or γ-mercaptopropyltriethoxysilane, and the polyepoxy organosilane is at least one of epoxycyclohexylcyclotetrasiloxane, glycidyl etheroxypropylcyclotetrasiloxane, or glycidyl etheroxypropyl cage-like polysilsesquioxane.

[0012] Preferably, the adhesive layer is composed of at least one of polyacrylic acid, polyurethane, epoxy resin, EVA, POE or PES;

[0013] Preferably, the thickness of the adhesive layer is 10-100 μm.

[0014] Preferably, the insulating sealing tape further includes a waterproof layer, which is located on the side of the insulating layer that is close to or far from the adhesive layer.

[0015] Preferably, the waterproof layer is composed of at least one of a metal, a metal oxide, or silicon oxide;

[0016] Preferably, the thickness of the waterproof layer is 0.005-50 μm.

[0017] Preferably, the width of the insulating sealing tape for the photovoltaic module is 5-30mm.

[0018] The present invention also proposes a photovoltaic module encapsulation structure, including the above-mentioned insulating sealing tape.

[0019] Preferably, the insulating sealing tape wraps at least one side of the photovoltaic module so that the creepage distance extends along the thickness direction of the photovoltaic module.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0021] (1) In this invention, the insulating sealing tape includes an insulating layer and an adhesive layer that are sequentially laminated from top to bottom. The relative temperature index (RTI) of the insulating layer is greater than or equal to 90°C, the breakdown voltage is greater than or equal to 8KV, and the tracking index (CTI) is greater than or equal to 175V. By controlling the insulating layer to meet the above-mentioned electrical insulation effects, the creepage distance is increased. The insulating layer is firmly bonded to the side of the photovoltaic module laminate by the adhesive layer, so as to achieve the edge-wrapping effect of the insulating sealing tape on at least one side of the photovoltaic module.

[0022] (2) In this invention, after the photovoltaic module frame and the photovoltaic module are wrapped with insulating edge sealing tape, the creepage distance extends along the insulating edge sealing tape. This effectively increases the creepage distance and allows the solar cells to be close to the edge of the photovoltaic module body, reducing the blank area, thereby increasing the filling density of the solar cell body and increasing the conversion efficiency of the photovoltaic module body. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the photovoltaic module insulating sealing tape described in this invention;

[0024] Figure 2 This is a schematic diagram of the photovoltaic module encapsulation structure described in this invention. Detailed Implementation

[0025] Reference Figure 1 The present invention proposes a photovoltaic module insulating sealing tape, comprising an insulating layer 11 and an adhesive layer 12 located on one side surface of the insulating layer 11;

[0026] The relative temperature index (RTI) of insulation layer 11 is greater than or equal to 90℃, the breakdown voltage is greater than or equal to 8KV, and the tracking index is greater than or equal to 175V.

[0027] In this invention, the insulating layer, as the core structural layer of the entire tape, needs to meet the insulation performance requirements of the standard. According to the working voltage requirements of different photovoltaic modules, the breakdown voltage requirement is 8000-10000V / mm. Therefore, the breakdown voltage of the insulating layer 11 must be ≥8000V to meet the requirements. At the same time, the relative temperature index RTI must be ≥90℃ and the tracking index CTI must be ≥175V to meet the electrical safety requirements and ensure that the creepage distance can be extended.

[0028] The adhesive layer 12 is used to provide good adhesion and sealing performance, which can firmly bond the insulating layer 11 to the side of the photovoltaic module laminate, and realize the edge wrapping of the insulating sealing tape on at least one side of the photovoltaic module.

[0029] Generally, the 90° peel strength of the adhesive layer 12 from the surface of the photovoltaic module (such as glass, THV backsheet material, PVDF backsheet material, PVF backsheet material, etc.) needs to be higher than 1 N / cm.

[0030] In one embodiment, the insulating sealing tape 1 further includes a waterproof layer 13, which is located on the side of the insulating layer 11 away from the adhesive layer 12.

[0031] In traditional photovoltaic (PV) module encapsulation structures, silicone is used for sealing and connection. However, during use, external moisture can easily penetrate the PV module through the silicone. This moisture not only corrodes the solar cells but also affects the adhesion of the silicone film, thus impacting the reliability and lifespan of the PV module. Therefore, when the insulating sealing tape 1 also includes a waterproof layer 13, the waterproof layer 13 provides a moisture barrier, preventing moisture from penetrating from the edges of the PV module and corroding its interior.

[0032] In one embodiment, the insulating layer 11 is composed of at least one of polyolefins and their copolymers, polyurethanes, glass fiber composites, polyimides, polyetherimides, or fluorinated polymers.

[0033] In one embodiment, the insulating layer 11 is composed of a polyester layer and a modified epoxy resin insulating coating located on one side surface of the polyester layer.

[0034] In this invention, the modified epoxy resin insulating coating is formed by coating and curing an insulating barrier liquid onto one side of the polyester layer. The insulating barrier liquid comprises, by weight, 100 parts epoxy resin, 20-30 parts organosilicon-modified nano boron nitride, 1-5 parts curing agent, and 50-60 parts ethyl acetate.

[0035] The organosilicon-modified nano-boron nitride is obtained by coupling nano-boron nitride with a mercaptosilane coupling agent, followed by a "thiol-epoxy" click chemical reaction with a polyepoxy organosilicon.

[0036] In the aforementioned insulation layer, the insulating coating uses epoxy resin and silicone-modified nano-boron nitride as the main components. Silicone-modified nano-boron nitride, on the one hand, possesses high resistivity and breakdown strength, as well as extremely high thermal stability, thus effectively improving the insulation performance of the insulation layer and enhancing its adaptability and service life under harsh conditions such as high temperature, high humidity, and chemical corrosion. On the other hand, due to the surface grafting of polyepoxysilanes, it can form a cured cross-linked structure with the epoxy resin, ensuring the effective insulation modification of nano-boron nitride. Furthermore, the hydrophobic effect of silicone further provides a water vapor barrier, thus providing another barrier to prevent water vapor from entering the photovoltaic module.

[0037] In one embodiment, the adhesive layer 12 is composed of at least one of polyacrylic acid, polyurethane, epoxy resin, EVA, POE, or PES. For example, it can be a pressure-sensitive adhesive or a hot melt adhesive, and the adhesive layer must be free of air bubbles after being bonded to the edge of the photovoltaic module.

[0038] In one embodiment, the waterproof layer 13 is composed of at least one of metal, metal oxide, or silicon oxide. When the waterproof layer 13 is composed of metal, such as metal foil, the waterproof layer 13 is located on the side of the insulating layer 11 away from the adhesive layer 12; however, when the waterproof layer 13 is composed of metal oxide or silicon oxide, the waterproof layer 13 is located on the side of the insulating layer 11 closer to the adhesive layer 12, that is, the waterproof layer 13 is between the insulating layer 11 and the adhesive layer 12.

[0039] When the waterproof layer 13 is made of metal, the metal can be metal foil, such as aluminum foil or copper foil. Aluminum foil and copper foil have certain mechanical strength and good ductility, which can be used to make thin metal foil layers. Aluminum foil and copper foil have good weather resistance and can maintain good moisture barrier ability even after long-term use compared to conventional materials such as PET. In actual production, the waterproof layer 13 can be made by gluing a layer of metal foil to the outside of the insulation layer with adhesive, or by preparing a metal coating through vacuum evaporation.

[0040] In one implementation method, the width of the insulating sealing tape 1 is 5-30mm. In this invention, if the tape width is too narrow, the contact area between the tape and the photovoltaic module is too small, making it unable to stably cover the edge of the photovoltaic module. At the same time, the bonding surface between the tape and the photovoltaic module is also small, resulting in poor bonding effect. If the tape width is too wide, it will cause the tape to cover too much of the top and bottom of the photovoltaic module, blocking light and thus affecting the power generation efficiency of the photovoltaic module.

[0041] In one embodiment, the insulating layer 11 of the insulating sealing tape has a thickness of 0.3-1 mm, and the adhesive layer has a thickness of 10-100 μm. In this invention, by controlling the thickness as described above, the following is avoided: if the tape thickness is too small, the tape strength will be low, and the tape will crack during hot pressing, affecting its use; if the tape thickness is too large, the tape will have poor adhesion at edges and corners, resulting in poor bonding with the photovoltaic module edges and easy tape detachment.

[0042] Reference Figure 2 The present invention also provides a photovoltaic module encapsulation structure, including an insulating edge sealing tape 1, a photovoltaic module 2, and an encapsulation frame 3;

[0043] The photovoltaic module 2 includes a front encapsulation panel 21, an encapsulation film 22, a solar cell 23, and an encapsulation backplate 24. The encapsulation film layer 22 wraps the solar cell 23 inside. The front encapsulation panel 21 and the encapsulation backplate 24 are located on the upper and lower surfaces of the encapsulation film layer 22, respectively. An insulating edge sealing tape 1 is attached to one side edge of the photovoltaic module 2 to wrap it. An encapsulation frame 3 is located on the outside of the insulating edge sealing tape 1.

[0044] Figure 2In the diagram, the yellow line represents the creepage distance without insulating edge sealing tape 1, and the red line represents the creepage distance with insulating edge sealing tape 1 applied. It can be seen that after the photovoltaic module frame is sealed with insulating edge sealing tape 1, the creepage distance extends along the insulating edge sealing tape 1.

[0045] The technical solution of the present invention will be described in detail below through specific embodiments. However, it should be clearly stated that these embodiments are for illustrative purposes only and are not intended to limit the scope of the present invention.

[0046] IXPE: from Junhui Company, grade 2426H;

[0047] Acrylic acid L: from Henkel, brand name DURO-TAK 1151;

[0048] HDPP: from Sinopec, grade 9006;

[0049] Polyurethane: from Kaiyang Company, grade W1085;

[0050] PET polyester layer: from Hubei Xiangyuan New Materials Co., Ltd.;

[0051] Silicone composite material layer: from Huitian Company, brand name Huitian HT906Z.

[0052] Example 1

[0053] A photovoltaic module insulating sealing tape includes an insulating layer and an adhesive layer, wherein the adhesive layer is located on one side surface of the insulating layer;

[0054] The insulating layer is a 300μm thick IXPE layer; the adhesive layer is a 55μm thick acrylic L layer.

[0055] Example 2

[0056] A photovoltaic module insulating sealing tape includes an insulating layer, an adhesive layer, and a waterproof layer, wherein the adhesive layer and the waterproof layer are located on both sides of the insulating layer, respectively.

[0057] The insulation layer is a 300μm thick IXPE layer; the adhesive layer is a 55μm thick acrylic L layer; and the waterproof layer is a 7μm thick aluminum foil, which is bonded to the surface of the insulation layer by polyurethane.

[0058] Example 3

[0059] A photovoltaic module insulating sealing tape includes an insulating layer and an adhesive layer, wherein the adhesive layer is located on one side surface of the insulating layer;

[0060] The insulating layer is a 300μm thick HDPP layer; the adhesive layer is a 55μm thick acrylic L layer (with 1wt% crosslinking agent 101 added).

[0061] Example 4

[0062] A photovoltaic module insulating sealing tape includes an insulating layer, an adhesive layer, and a waterproof layer, wherein the adhesive layer and the waterproof layer are located on both sides of the insulating layer, respectively.

[0063] The insulation layer is a 300μm thick IXPE layer; the adhesive layer is a 55μm thick acrylic L layer (with 1wt% crosslinking agent 101 added); the waterproof layer is a 15μm thick aluminum foil, which is bonded to the surface of the insulation layer by polyurethane.

[0064] Example 5

[0065] An insulating sealing tape for photovoltaic modules includes an insulating layer and an adhesive layer;

[0066] The insulating layer consists of a PET polyester layer (250 μm) and a modified epoxy resin insulating coating (50 μm) located on one side of the PET polyester layer. The modified epoxy resin insulating coating is formed by mixing 100 parts by weight of epoxy resin E-511, 25 parts by weight of organosilicon-modified nano boron nitride, 3 parts by weight of triethylenetetramine and 55 parts by weight of ethyl acetate, coating it onto the surface of the PET polyester layer, and curing it at 100°C for 6 hours.

[0067] The organosilicon-modified nano-boron nitride was prepared by the following method: Nano-boron nitride (200 nm in diameter) was added to a 0.5 mol / L sodium hydroxide aqueous solution and ultrasonically dispersed until uniform. The solution was heated to 70°C and reacted for 4 hours. After centrifugation, the nano-boron nitride was added to an ethanol-water (9:1) solution containing 3 wt% γ-mercaptopropyltrimethoxysilane. The solution was heated to 60°C and reacted for 3 hours. The mixture was filtered, washed with anhydrous ethanol, and dried to obtain mercapto-modified nano-boron nitride. The mercapto-modified nano-boron nitride, glycidyl etheroxypropylcyclotetrasiloxane, triethylamine, and anhydrous ethanol were mixed in a mass ratio of 1.5:1:0.2:50 and stirred for 8 hours. The mixture was filtered, washed with anhydrous ethanol, and dried to obtain the organosilicon-modified nano-boron nitride.

[0068] The structural diagram of the organosilicon-modified nano-boron nitride is as follows:

[0069]

[0070] The adhesive layer is an acrylic adhesive with a thickness of 55 μm, and the adhesive layer is located on the side surface of the insulating layer with a modified epoxy resin insulating coating.

[0071] Comparative Example 1

[0072] A photovoltaic module insulating sealing tape includes an insulating layer and an adhesive layer, wherein the adhesive layer is located on one side surface of the insulating layer;

[0073] The insulating layer is a 300μm thick silicone composite material layer; the adhesive layer is a 55μm thick acrylic adhesive L layer.

[0074] Comparative Example 2

[0075] An insulating sealing tape for photovoltaic modules includes an insulating layer and an adhesive layer;

[0076] The insulating layer consists of a PET polyester layer (250 μm) and a modified epoxy resin insulating coating (50 μm) on one side of the PET polyester layer. The modified epoxy resin insulating coating is formed by mixing 100 parts by weight of epoxy resin E-511, 25 parts by weight of nano boron nitride modified by mercaptosilane coupling agent, 3 parts by weight of triethylenetetramine, and 55 parts by weight of ethyl acetate, coating it onto the surface of the PET polyester layer, and curing it at 100°C for 6 hours.

[0077] The mercaptosilane coupling agent modified boron nitride nanoparticles were prepared by the following method: boron nitride nanoparticles (200 nm in diameter) were added to a 0.5 mol / L sodium hydroxide aqueous solution and ultrasonically dispersed evenly. The mixture was heated to 70 °C and reacted for 4 h. After centrifugation, the mixture was added to an ethanol-water (9:1) solution containing 3 wt% γ-mercaptopropyltrimethoxysilane and heated to 60 °C and reacted for 3 h. The mixture was then filtered, washed with anhydrous ethanol, and dried to obtain mercaptosilane coupling agent modified boron nitride nanoparticles.

[0078] The adhesive layer is an acrylic adhesive with a thickness of 55 μm, and the adhesive layer is located on the side surface of the insulating layer with a modified epoxy resin insulating coating.

[0079] Comparative Example 3

[0080] An insulating sealing tape for photovoltaic modules includes an insulating layer and an adhesive layer;

[0081] The insulating layer consists of a PET polyester layer (250 μm) and a modified epoxy resin insulating coating (50 μm) located on one side of the PET polyester layer. The modified epoxy resin insulating coating is formed by mixing 100 parts by weight of epoxy resin E-511, 25 parts by weight of epoxy silane coupling agent modified nano boron nitride, 3 parts by weight of triethylenetetramine and 55 parts by weight of ethyl acetate, coating it onto the surface of the PET polyester layer, and curing it at 100°C for 6 hours.

[0082] The epoxy silane coupling agent modified nano boron nitride was prepared by the following method: nano boron nitride (200 nm in diameter) was added to a 0.5 mol / L sodium hydroxide aqueous solution and ultrasonically dispersed evenly. The solution was heated to 70 °C and reacted for 4 h. After centrifugation, the nano boron nitride was added to an ethanol-water (9:1) solution containing 3 wt% γ-glycidoxypropyltrimethoxysilane and heated to 60 °C and reacted for 3 h. The solution was filtered, washed with anhydrous ethanol, and dried to obtain epoxy silane coupling agent modified nano boron nitride.

[0083] The adhesive layer is an acrylic adhesive with a thickness of 55 μm, and the adhesive layer is located on the side surface of the insulating layer with a modified epoxy resin insulating coating.

[0084] Performance testing:

[0085] The insulating sealing tapes prepared according to the methods in IEC 61215-2 and IEC 61730-2 standards were subjected to performance tests. The test results are shown in Table 1.

[0086] Table 1. Performance test results of the insulating sealing tape for the photovoltaic modules described in the examples and comparative examples.

[0087]

[0088] As can be seen from the table above, the insulating sealing tape of the present invention includes an insulating layer and an adhesive layer sequentially laminated from top to bottom. By controlling the insulating layer to meet the above-mentioned electrical insulation effect, the creepage distance is increased. The adhesive layer firmly bonds the insulating layer to the side of the photovoltaic module laminate, thereby achieving the edge-wrapping effect of the insulating sealing tape on at least one side of the photovoltaic module.

[0089] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A photovoltaic module insulating edge sealing tape, characterized in that, Includes an insulating layer and an adhesive layer located on one side of the insulating layer; The insulation layer has a relative temperature index (RTI) greater than or equal to 90°C, a breakdown voltage greater than or equal to 8KV, and a tracking index (CTI) greater than or equal to 175V.

2. The photovoltaic module insulating sealing tape according to claim 1, characterized in that, The insulating layer is composed of at least one of polyolefins and their copolymers, polyurethane, glass fiber composites, polyimide, polyetherimide or fluorinated polymers; Preferably, the thickness of the insulating layer is 0.3-1 mm.

3. The photovoltaic module insulating sealing tape according to claim 1, characterized in that, The insulating layer is composed of a polyester layer and a modified epoxy resin insulating coating located on one side of the polyester layer.

4. The photovoltaic module insulating sealing tape according to claim 3, characterized in that, The modified epoxy resin insulating coating is an epoxy resin insulating coating containing organosilicon-modified nano boron nitride. Preferably, the organosilicon-modified nano-boron nitride is obtained by coupling nano-boron nitride with a mercaptosilane coupling agent, followed by a "thiol-epoxy" click chemical reaction with a polyepoxy organosilicon. Preferably, the mercaptosilane coupling agent is γ-mercaptopropyltrimethoxysilane or γ-mercaptopropyltriethoxysilane, and the polyepoxy organosilane is at least one of epoxycyclohexylcyclotetrasiloxane, glycidyl etheroxypropylcyclotetrasiloxane, or glycidyl etheroxypropyl cage-like polysilsesquioxane.

5. The photovoltaic module insulating sealing tape according to any one of claims 1-4, characterized in that, The adhesive layer is composed of at least one of polyacrylic acid, polyurethane, epoxy resin, EVA, POE or PES; Preferably, the thickness of the adhesive layer is 10-100 μm.

6. The photovoltaic module insulating sealing tape according to any one of claims 1-5, characterized in that, It also includes a waterproof layer located on the side of the insulation layer that is close to or away from the adhesive layer.

7. The photovoltaic module insulating sealing tape according to claim 6, characterized in that, The waterproof layer is composed of at least one of a metal, a metal oxide, or silicon oxide. Preferably, the thickness of the waterproof layer is 0.005-50 μm.

8. The photovoltaic module insulating sealing tape according to any one of claims 1-7, characterized in that, The width of the insulating sealing tape is 5-30mm.

9. A photovoltaic module encapsulation structure, characterized in that, Including the insulating sealing tape according to any one of claims 1-8.

10. The photovoltaic module encapsulation structure according to claim 9, characterized in that, The insulating sealing tape wraps at least one side of the photovoltaic module so that the creepage distance extends along the thickness direction of the photovoltaic module.

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