Low-flow high-adhesion light-conversion integrated adhesive film for main-grid-free photovoltaic module

Abstract

The utility model relates to the technical field of photovoltaic modules, in particular to a low-flow high-adhesion light conversion integrated adhesive film for a main-grid-free photovoltaic module, which comprises a low-flow adhesion layer, the low-flow adhesion layer is connected with a light conversion layer through a low-flow cut-off layer, the low-flow adhesion layer is connected with a battery piece, and the light conversion layer is connected with glass. The thickness of the low-flow bonding layer is 20-100 m, and the pre-crosslinking degree is 45-55%; the thickness of the low flow cut-off layer is 50-200m, and the pre-crosslinking degree is 45-55%; the thickness of the light conversion layer is 200-400 m. The low-flow high-adhesion light-conversion integrated adhesive film for the main-grid-free photovoltaic module is simple in manufacturing process, easy to operate, green, environment-friendly and suitable for industrial production; the low-flowability high-adhesion light-conversion integrated adhesive film for the main-grid-free photovoltaic module has the advantages of being low in flowability, high in adhesion force, capable of improving the initial power of the module and capable of reducing UV attenuation of the module.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic module technology, and in particular to a low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules. Background Technology

[0002] With technological advancements, solar cell busbar technology has evolved from MBB and SMBB to OBB (busbar-less). Busbar-less technology is a further upgrade of SMBB technology, offering significant cost reduction advantages. It directly eliminates the main busbar in the cell, further reducing silver loss. Additionally, in the module assembly, copper solder strips replace the original busbar's function of conducting current. While MBB modules typically use solder strips with a diameter of 0.2-0.4 mm, OBB modules only require 0.2 mm, resulting in a smaller shading area and increased module power. Currently, busbar-less technology is widely used in TOPCon, XBC, and HJT cells.

[0003] Currently, the main technologies for busbarless HJT modules include SmartWire, adhesive printing, film coating, and welding adhesive application. Among these, adhesive printing is the most widely used and has already been mass-produced by leading busbarless HJT companies. However, three challenges remain for busbarless HJT modules: First, while adhesive printing equipment is simple and stable, it suffers from issues such as shadows under the solder ribbon during EL testing and insufficient adhesion between the solder ribbon and the cell. Second, the surface of busbarless HJT cells is a TCO layer, which has very low adhesion to conventional adhesive films, easily leading to delamination between the film and the cell. Third, busbarless HJT cells are sensitive to ultraviolet light; if a cut-off adhesive film is not used, the module's UV aging power decay is significant. Even if a high-efficiency cut-off adhesive film is used, the initial power of the module decreases as the UV transmittance of the adhesive film decreases.

[0004] To address the aforementioned issues, the use of low-flow, high-adhesion light-converting films is of great significance for the practical application of gridless solar cells. Summary of the Invention

[0005] The technical problem to be solved by this utility model is to provide a low-flow, high-adhesion integrated light-conversion film for gridless photovoltaic modules to solve the above-mentioned problems.

[0006] The technical solution of this utility model to solve the above-mentioned technical problems is: a low-flow, high-adhesion light-conversion integrated adhesive film for gridless photovoltaic modules, comprising a low-flow adhesive layer, wherein the low-flow adhesive layer is connected to the light-conversion layer through a low-flow cut-off layer, the low-flow adhesive layer is connected to the solar cell, and the light-conversion layer is connected to the glass.

[0007] As a preferred embodiment of this utility model, the low-flow adhesive layer is made of one or a combination of several of the following: ethylene-octene copolymer, ethylene-butene copolymer, and ethylene-hexene copolymer.

[0008] As a preferred embodiment of this invention, the low-flow adhesive layer has a thickness of 20-100 μm and a pre-crosslinking degree of 45-55% after pretreatment. The main functions of the low-flow adhesive layer are: firstly, to firmly fix the welding wire using its low-flow characteristics; secondly, to firmly bond the adhesive film, welding wire, and battery cell using its high-adhesion characteristics without delamination; and thirdly, to prevent water vapor erosion and ensure module reliability due to its low water permeability.

[0009] As a preferred embodiment of this invention, the low-flow cutoff layer is made of one or more of the following materials: ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, or ethylene-methyl acrylate copolymer.

[0010] As a preferred embodiment of this invention, the low-flow cutoff layer has a thickness of 50-200 μm and a pre-crosslinking degree of 45-55% after pretreatment. The main functions of the low-flow cutoff layer are: firstly, to utilize its low-flow characteristics in conjunction with the low-flow adhesive layer to further secure the welding wire; and secondly, to protect the battery by using UV cutoff agents of different wavelengths according to the UV decay curves of different solar cells, thereby reducing UV decay of the module.

[0011] As a preferred embodiment of this utility model, the light-converting layer is made of one or more of the following: ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, and ethylene-methyl acrylate copolymer.

[0012] As a preferred embodiment of this invention, the thickness of the light-converting layer is 200-400 μm.

[0013] In a preferred embodiment of this invention, the light-converting material in the light-converting layer is one or more of rare-earth inorganic light-converting agents, rare-earth organic light-converting agents, quantum dots, and organic fluorescent light-converting agents. The light-converting layer does not require pretreatment to ensure fluidity and avoid appearance problems such as insufficient adhesive or incomplete melting in the photovoltaic module. As a base layer, the main function of the light-converting layer is to utilize the light-converting material to increase the module's power output and, together with the low-flow cutoff layer, block the ultraviolet bands that are detrimental to the cells, thereby protecting the cells and reducing UV degradation of the module.

[0014] Because this utility model adopts such a structure, it has the following beneficial effects:

[0015] 1. The low-flow, high-adhesion integrated light-conversion film for the gridless photovoltaic module of this utility model has a simple, easy-to-operate, green and environmentally friendly manufacturing process that is suitable for industrial production.

[0016] 2. The low-flow, high-adhesion integrated light-converting film for gridless photovoltaic modules produced by this utility model has the characteristics of low flowability, high adhesion, improved initial power of the module, and reduced UV attenuation of the module. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a low-flow, high-adhesion integrated light-converting film for gridless photovoltaic modules according to this utility model.

[0018] In the figure: 1 is the low-flow adhesive layer, 2 is the low-flow cutoff layer, and 3 is the light-converting layer. Detailed Implementation

[0019] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, the present invention discloses a low-flow, high-adhesion light-converting integrated film for gridless photovoltaic modules, characterized in that it includes a low-flow adhesive layer 1, which is connected to the light-converting layer 3 through a low-flow cut-off layer 2.

[0021] Example 1

[0022] The low-flow, high-adhesion integrated light-conversion film for gridless photovoltaic modules consists of a low-flow adhesive layer, a low-flow cut-off layer, and a light-conversion layer. The low-flow adhesive layer is an ethylene-octene copolymer with a thickness of 20 μm and a pre-crosslinking degree of 55% after pretreatment. The low-flow cut-off layer is an ethylene-vinyl acetate copolymer with a thickness of 50 μm and a pre-crosslinking degree of 55% after pretreatment. The light-conversion layer is an ethylene-vinyl acetate copolymer with a thickness of 200 μm, and the light-conversion material is a rare-earth organic light-conversion agent.

[0023] Example 2

[0024] The low-flow, high-adhesion integrated light-conversion film for gridless photovoltaic modules consists of a low-flow adhesive layer, a low-flow cut-off layer, and a light-conversion layer. The low-flow adhesive layer is an ethylene-butene copolymer with a thickness of 20 μm and a pre-crosslinking degree of 50% after pretreatment. The low-flow cut-off layer is an ethylene-vinyl acetate copolymer with a thickness of 100 μm and a pre-crosslinking degree of 50% after pretreatment. The light-conversion layer is an ethylene-vinyl acetate copolymer with a thickness of 300 μm, and the light-conversion material is an organic fluorescent light-converting agent.

[0025] Example 3

[0026] The low-flow, high-adhesion integrated light-conversion film for gridless photovoltaic modules consists of a low-flow adhesive layer, a low-flow cut-off layer, and a light-conversion layer. The low-flow adhesive layer is an ethylene-hexene copolymer with a thickness of 100 μm and a pre-crosslinking degree of 45% after pretreatment. The low-flow cut-off layer is an ethylene-acrylic acid copolymer with a thickness of 200 μm and a pre-crosslinking degree of 45% after pretreatment. The light-conversion layer is an ethylene-methyl acrylate copolymer with a thickness of 400 μm, and the light-conversion material is a rare-earth organic light-conversion agent.

[0027] Comparative Example 1

[0028] The low-flow, high-adhesion light-conversion integrated film for gridless photovoltaic modules consists of a low-flow cutoff layer and a light-conversion layer. The low-flow cutoff layer is an ethylene-vinyl acetate copolymer with a thickness of 100 μm and a pre-crosslinking degree of 50% after pretreatment. The light-conversion layer is an ethylene-vinyl acetate copolymer with a thickness of 300 μm, and the light-conversion material is an organic fluorescent light-converting agent.

[0029] Comparative Example 2

[0030] The low-flow, high-adhesion light-conversion integrated film for gridless photovoltaic modules consists of a low-flow adhesive layer and a light-conversion layer. The low-flow adhesive layer is an ethylene-butene copolymer with a thickness of 20 μm, and its pre-crosslinking degree is 50% after pretreatment. The light-conversion layer is an ethylene-vinyl acetate copolymer with a thickness of 300 μm, and the light-conversion material is an organic fluorescent light-converting agent.

[0031] Comparative Example 3

[0032] The low-flow, high-adhesion integrated light-converting film for gridless photovoltaic modules consists of a light-converting layer, which is an ethylene-vinyl acetate copolymer with a thickness of 300 μm. The light-converting material is an organic fluorescent light-converting agent.

[0033] The module manufacturing process is as follows: First, low-temperature welding wires are arranged on the solar cells. Then, UV adhesive is applied to fix the welding wires on the solar cells. Finally, an adhesive film and glass are applied, and the modules are laminated to form a module containing 144 solar cells. The module's UV resistance is tested according to GB / T 29848-2018, and the appearance defects such as welding wire slippage and bubbles around the welding ribbons are observed, as well as whether there is shadowing on the EL (electroluminescent substrate).

[0034] Table 1 Performance tests of Example 1 and Comparative Examples 1-3

[0035]

[0036] As shown in Table 1, the low-flow, high-adhesion integrated light-converting film for gridless photovoltaic modules produced by this invention has the characteristics of low flowability, high adhesion, improved initial power of the module, and reduced UV attenuation of the module.

[0037] The description and application of this utility model herein are illustrative and not intended to limit the scope of the utility model to the embodiments described above. Variations and modifications of the embodiments disclosed herein are possible, and practical substitutions and equivalent components of the embodiments are well known to those skilled in the art. It will be apparent to those skilled in the art that this utility model can be implemented in other forms, structures, arrangements, proportions, and with other elements, materials, and components without departing from the spirit or essential characteristics of the utility model. Other variations and modifications can be made to the embodiments disclosed herein without departing from the spirit or essential characteristics of the utility model.

Claims

1. A low-flow, high-adhesion integrated light transfer film for gridless photovoltaic modules, characterized in that: It includes a low-flow adhesive layer (1), which is connected to the light-converting layer (3) through a low-flow cut-off layer (2); The low-flow adhesive layer (1) is made of ethylene-octene copolymer, ethylene-butene copolymer, or ethylene-hexene copolymer; The low flow stop layer (2) is made of ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, or ethylene-methyl acrylate copolymer. The light-converting layer (3) is made of ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, or ethylene-methyl acrylate copolymer.

2. The low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules according to claim 1, characterized in that: The low flow cutoff layer (2) and the light conversion layer (3) are made of the same material.

3. The low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules according to claim 1, characterized in that: The thickness of the low-flow adhesive layer (1) is 20-100µm, and the degree of pre-crosslinking is 45-55%.

4. The low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules according to claim 1, characterized in that: The low flow cutoff layer (2) has a thickness of 50-200µm and a pre-crosslinking degree of 45-55%.

5. The low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules according to claim 1, characterized in that: The thickness of the light-converting layer (3) is 200-400µm.

6. The low-flow, high-adhesion integrated light-transfer film for gridless photovoltaic modules according to claim 1, characterized in that: The thickness of the adhesive film is 270-700µm.

Images