Packaging structure of flexible photovoltaic module

Abstract

The utility model provides a packaging structure of a flexible photovoltaic assembly, a laminated structure of the packaging structure comprises a front plate, a crystalline silicon cell layer, an EVA layer and a back plate from front to back in sequence, the periphery of the laminated structure is a frame, and flexible insulation parts are arranged between the frame and the end portion of the laminated structure, between the upper side of the end portion and between the lower side of the end portion. The edge part of the laminated structure extends into the flexible insulating part and the frame by a set distance; a PVDF film is arranged on the surface of the PET substrate of the front plate, an aluminum oxide ceramic wear-resistant layer is formed on the PVDF film, and a silicon oxide or silicon nitride film layer is arranged on the back face of the PET substrate. According to the packaging structure of the flexible photovoltaic module, the PET substrate and the high-density polyethylene insulating substrate with certain strength and toughness are used as front and rear main structural materials for packaging the module, and the fluorine-containing high polymer material film and the silicon oxide or silicon nitride film layer are combined; the anti-ultraviolet and anti-aging performance of the assembly is improved; and the PID effect of the assembly can be obviously reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic power generation, in particular to a packaging structure of a flexible photovoltaic component. Background Art

[0002] The photovoltaic power generation system is a power generation system that directly converts solar energy into electrical energy. It can take into account both economic development and ecological protection while generating clean electricity. It is currently widely used in a variety of scenarios. It is one of the important clean energy sources to replace traditional fossil energy and has broad development prospects.

[0003] Photovoltaic power generation system is to connect photovoltaic modules through cables to form a module array, and then directly provide the electricity generated by photovoltaic modules to the power load or integrate it into the power grid through branch lines, busbars, DC / AC conversion. At present, photovoltaic systems are generally built in the sparsely populated central and western regions, with flat terrain, large areas of deserts, saline-alkali land, etc. In the developed eastern regions, due to limited land resources, it is impossible to provide open space to install centralized photovoltaic power generation modules. In this scenario, distributed photovoltaic power stations installed on the roof have become the main form of application. Traditional glass packaging components are heavy, and a large number of components will cause the roof of the building to bear too much pressure. The bracket installation of fixed photovoltaic modules will also damage the original house structure, which will hinder the further promotion of distributed rooftop photovoltaic power generation. The lighter flexible photovoltaic modules are more suitable for this application scenario. Flexible photovoltaic modules are a new type of module that is lighter, thinner and more flexible than traditional glass packaging modules. They can be directly attached to light loads and curved roofs, and basically do not require brackets or other installation systems. As for lightweight flexible modules, the earliest ones were made of thin-film batteries. The photoelectric conversion efficiency of thin-film batteries is much lower than that of crystalline silicon modules. In recent years, with the development of crystalline silicon technology and the improvement of packaging materials, new and efficient crystalline silicon lightweight flexible modules have also been developed. For the packaging of flexible photovoltaic modules, it is necessary to meet the requirements of lightness, flexibility, and minimize or avoid the problem of hidden cracks in the cells during the production process. Utility Model Content

[0004] The purpose of the utility model is to adapt to the application requirements of flexible photovoltaic components and propose a packaging structure of flexible photovoltaic components, which can make the flexible photovoltaic components light and flexible, and at the same time have a certain rigidity to meet the structural requirements of fixing the flexible photovoltaic components to the roof.

[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:

[0006] A packaging structure for a flexible photovoltaic module. The lamination structure of the packaging structure is, from front to back, a front plate, a crystalline silicon cell layer, an EVA layer, and a back plate. The perimeter of the lamination structure is a frame. A flexible insulating component is provided between the frame and the ends, upper sides of the ends, and lower sides of the ends of the lamination structure. The edge portion of the lamination structure extends into the flexible insulating component and the interior of the frame by a set distance; The front plate includes a PET substrate in the middle, a PVDF film adhesively bonded to the front surface of the PET substrate, an alumina ceramic wear-resistant layer formed on the PVDF film by a coating process, and a silicon oxide or silicon nitride thin film layer formed on the back surface of the PET substrate by a deposition process; The back plate includes a high-density polyethylene insulating substrate at the bottom and a silicon oxide or silicon nitride thin film layer formed on the surface of the insulating substrate by a deposition process. Reinforcing ribs are provided at uniform intervals on the back surface of the insulating substrate.

[0007] Preferably, the thickness of the PET substrate of the front plate is 300 - 500 microns, the thickness of the PVDF film is 25 - 40 microns, and the thickness of the alumina ceramic wear-resistant layer is 10 - 15 microns.

[0008] More preferably, the surface of the PET substrate is a surface with a certain roughness formed by sandpaper grinding or surface modification treatment with a silane coupling agent.

[0009] More preferably, the thickness of the high-density polyethylene insulating substrate is 400 - 800 microns; the thickness of the silicon oxide or silicon nitride thin film layer is 25 - 30 microns.

[0010] More preferably, the reinforcing ribs are provided at positions corresponding to the gaps between the battery cells.

[0011] More preferably, the photovoltaic module is an N-type back-contact crystalline silicon cell module.

[0012] More preferably, a grounding terminal is provided on the frame of the photovoltaic module.

[0013] The beneficial effect of the present utility model is that for the packaging structure of the flexible photovoltaic module, PET substrates and high-density polyethylene insulating substrates with a certain strength and toughness are used as the main structural materials for the front and back of the module packaging, combined with fluorine-containing polymer material films and silicon oxide or silicon nitride thin film layers, to improve the anti-ultraviolet and anti-aging properties of the module and significantly reduce the PID effect of the module. Compared with the traditional use of ethylene-tetrafluoroethylene copolymer as the main packaging material, the module has significantly better flexibility and resistance to damp heat aging and ultraviolet aging. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic structural diagram of a packaging structure of a flexible photovoltaic module according to an embodiment of the present utility model;

[0015] Figure 2 Shown is Figure 1 a schematic structural view of the front plate of the encapsulation structure in

[0016] Figure 3 Shown is Figure 1 a schematic structural view of the back plate of the encapsulation structure in Detailed implementation manners

[0017] To further understand the purpose, structure, features and functions of the present utility model, the following provides a detailed description in conjunction with embodiments.

[0018] To make the purpose, technical solutions and advantages of the present utility model clearer, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are some, but not all, of the embodiments of the present utility model. All other embodiments obtained by those of ordinary skill in the art based on the described embodiments of the present utility model without creative efforts fall within the protection scope of the present utility model. It can be understood that, without conflict, some technical means described in the various embodiments herein may be replaced or combined with each other.

[0019] In the description of the present utility model, if there are terms such as "first", "second", etc., they are only used to distinguish the described objects and do not have any sequential or technical meaning. Thus, the objects defined with "first", "second", etc. may explicitly or implicitly include one or more of such objects. And, words such as "one" or "a" do not indicate a quantity limitation, but rather indicate the existence of at least one, and "a plurality" means not less than two.

[0020] Referring to Figure 1 the schematic structural view of an encapsulation structure of a flexible photovoltaic module according to an embodiment of the present utility model shown in Figure 2 As shown, the front plate 11 includes a PET (polyethylene terephthalate) substrate 112 in the middle, a PVDF (polyvinylidene fluoride) film adhesively bonded to the front surface of the PET substrate, and a silicon oxide or silicon nitride film layer 114 formed on the back surface of the PET substrate by a deposition process; referring to Figure 3As shown, the backplane 14 includes an HDPE (high-density polyethylene) insulating substrate 141 located at the bottom and a silicon oxide or silicon nitride thin film layer 142 formed on the surface of the insulating substrate by a deposition process.

[0021] For the packaging structure of the flexible photovoltaic module of the present utility model, the front plate uses a PET substrate with certain strength and toughness as the main structural material, and a polyvinylidene fluoride film is provided thereon. This film is a fluorine-containing polymer material. Since photovoltaic modules are all applied outdoors, long-term ultraviolet irradiation will damage the encapsulation adhesive film and the solar cells. Due to the highest electronegativity of fluorine element, small atomic radius, short C-F bond formed, and large bond energy, F atoms and perfluoro groups play a protective role for the main chain. Therefore, fluorine-containing polymer materials have many advantages such as heat resistance, ultraviolet resistance, and wear resistance, which can meet the household application conditions of photovoltaic modules. In addition, using the PET substrate with excellent flexibility and the high-density polyethylene insulating substrate as the main structural materials of the packaging structure can reduce the thickness of the polyvinylidene fluoride film with relatively high hardness and ensure that the module has sufficient flexibility.

[0022] In another embodiment, since the front surface (light-receiving surface) of the front plate of the photovoltaic module is relatively vulnerable to being affected by climate or environment and causing wear, such as abrasive wear caused by dust and corrosion wear caused by rainwater, etc., therefore, in order to ensure the service life of the photovoltaic module, a wear-resistant layer 116 can be formed on the outermost surface of the front plate, that is, on the surface of the polyvinylidene fluoride film layer, by a coating process. The wear-resistant layer can be an alumina wear-resistant ceramic layer with a thickness of 10-15 microns.

[0023] In addition, a silicon oxide or silicon nitride thin film layer is deposited on the back surface (inner side) of the front plate 11 and the surface (inner side) of the backplane 14 of the present utility model. On the one hand, it can play a role in preventing water vapor from entering the interior of the module, and on the other hand, it can play an antireflection passivation effect and reduce the potential-induced degradation (PID) effect of the photovoltaic module.

[0024] In a preferred embodiment, the thickness of the PET substrate of the front plate 11 is 300-500 microns, and the thickness of the PVDF film is 25-40 microns. In another preferred embodiment, in order to improve the bonding strength between the PVDF film and the surface of the PET substrate, the surface of the PET substrate is a surface with a certain roughness formed by sandpaper polishing or surface modification treatment with a silane coupling agent.

[0025] In another preferred embodiment, the thickness of the high-density polyethylene insulating substrate 141 is 400 - 800 microns; the thickness of the silicon oxide or silicon nitride thin film layers 114, 142 is 25 - 30 microns. Additionally, as the backplane that plays a major supporting role for the flexible photovoltaic module, in order to improve its supporting strength, a plurality of reinforcing ribs 1412 are evenly arranged at intervals on the back of the high-density polyethylene insulating substrate 141. In an even more preferred implementation, the reinforcing ribs 1412 are arranged at positions corresponding to the gaps between the battery cells. Since the gaps between the battery cells in the module are positions with relatively weak rigid strength, in this way, the supporting strength of the flexible module can be more effectively improved.

[0026] In another preferred implementation, the photovoltaic module is an N-type back-contact crystalline silicon cell module. In order to further reduce the PID effect of the module, as Figure 1 shown, a grounding terminal 102 is provided on the frame of the photovoltaic module. A flexible insulating component 16 such as insulating rubber is provided between the laminated structure of the package and the metal frame. On the one hand, it can ensure the sealing performance of the package structure and prevent water vapor from entering through the frame. On the other hand, it can cut off the leakage path of the current and further reduce the PID effect of the module.

[0027] The packaging structure of the flexible photovoltaic module of the present invention uses a PET substrate and a high-density polyethylene insulating substrate with certain strength and toughness as the main front and back structural materials for module packaging, and combines a fluorine-containing polymer material thin film and a silicon oxide or silicon nitride thin film layer to improve the anti-ultraviolet and anti-aging properties of the module and can significantly reduce the PID effect of the module. Compared with the traditional use of ethylene-tetrafluoroethylene copolymer as the main packaging material, the module has significantly better flexibility, anti-humid heat aging, and anti-ultraviolet aging properties.

[0028] The present invention has been described by the above related embodiments. However, the above embodiments are only examples for implementing the present invention. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, modifications and refinements made without departing from the spirit and scope of the present invention fall within the scope of patent protection of the present invention..

Claims

1. A packaging structure of a flexible photovoltaic module, characterized in that: The laminated structure of the packaging structure is a front plate, a crystalline silicon cell layer, an EVA layer, and a back plate from front to back. The laminated structure is surrounded by a frame. A flexible insulating component is provided between the frame and the end, the upper side of the end, and the lower side of the end of the laminated structure. The edge of the laminated structure extends into the flexible insulating component and the interior of the frame by a set distance. The front plate includes a PET substrate located in the middle, a PVDF film bonded to the front surface of the PET substrate by an adhesive, an alumina ceramic wear-resistant layer formed on the PVDF film by a coating process, and a silicon oxide or silicon nitride film layer formed on the back of the PET substrate by a deposition process. The back plate includes a high-density polyethylene insulating substrate located at the bottom and a silicon oxide or silicon nitride film layer formed on the surface of the insulating substrate by a deposition process, and reinforcing ribs with uniform intervals are provided on the back of the insulating substrate.

2. A packaging structure of a flexible photovoltaic module as claimed in claim 1, characterized in that: The thickness of the PET substrate of the front plate is 300-500 microns, the thickness of the PVDF film is 25-40 microns, and the thickness of the alumina ceramic wear-resistant layer is 10-15 microns.

3. A packaging structure of a flexible photovoltaic module as claimed in claim 2, characterized in that: The surface of the PET substrate is a surface with a certain roughness formed by sandpaper polishing or surface modification treatment with a silane coupling agent.

4. A packaging structure of a flexible photovoltaic module as claimed in claim 2, characterized in that: The thickness of the high-density polyethylene insulating substrate is 400-800 microns; the thickness of the silicon oxide or silicon nitride film layer is 25-30 microns.

5. The packaging structure of a flexible photovoltaic module according to claim 1, characterized in that: The reinforcing ribs are arranged at positions corresponding to the gaps between the battery sheets.

6. The packaging structure of a flexible photovoltaic module according to claim 4, characterized in that: The photovoltaic module is an N-type back-contact crystalline silicon cell module.

7. A packaging structure of a flexible photovoltaic module as claimed in claim 6, characterized in that: A grounding terminal is arranged on the frame of the photovoltaic module.

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