Light reflecting film and photovoltaic module with same

Abstract

The utility model provides a light reflecting film and a photovoltaic module with the same. The light reflecting film comprises a base material layer, the base material layer is provided with a first surface and a second surface which are oppositely arranged, and the first surface is provided with a microstructure; the reflecting layer is attached to the microstructure; the bonding layer is arranged on the outer surface of the base material layer and covers the reflecting layer; wherein the melting point of the base material layer is less than 155 DEG C. Through the technical scheme provided by the utility model, the photoelectric conversion efficiency can be effectively improved, the safety of the assembly is ensured, and the technical problem of insufficient weather resistance of the photovoltaic assembly in the prior art can be effectively solved.

Description

Technical Field

[0001] This utility model relates to the field of photovoltaic technology, and more specifically, to a light-reflecting film and a photovoltaic module having the same. Background Technology

[0002] Currently, photovoltaic (PV) modules primarily absorb sunlight directly through solar cells and convert it into electrical energy. In conventional PV module structures, gaps are typically maintained between adjacent cells and at the module edges. These gap areas account for approximately 10%-20% of the total module area. To fully utilize these areas, avoid wasting light energy, and improve conversion efficiency, reflective materials are usually incorporated into the PV module to reflect incident light from these areas.

[0003] Existing technologies include forming a reflective layer on the backsheet glass through an enamel coating process to improve the conversion efficiency of photovoltaic modules, or enamel coating only at the grid lines formed between the cells. However, the coefficient of thermal expansion of the enamel material differs from that of the glass material. Therefore, after enamel coating and subsequent high-temperature sintering and cooling processes, the mechanical properties of the backsheet glass are significantly reduced, the enamel-coated areas have poor impact resistance, and the risk is even higher at the edges. Moreover, when working outdoors, photovoltaic modules experience thermal expansion and contraction, increasing the risk of spontaneous glass breakage and posing serious safety hazards.

[0004] In existing technologies, different reflective materials are used as reflective materials in the gaps between solar cells. However, due to differences in the surface properties, melting temperature, chemical compatibility and hardness of different materials, the bonding force between the encapsulation material and other parts of the module is often not ideal. This leads to air gaps or interface separation inside the module, affecting the light transmittance and reflectance, reducing the power generation efficiency and weather resistance of the module, and even causing damage to the solar cells and resulting in economic losses. Utility Model Content

[0005] The main objective of this invention is to provide a light-reflecting film and a photovoltaic module having the same, which has the advantages of good reflectivity and high safety, and can effectively solve the technical problem of insufficient weather resistance of existing photovoltaic modules.

[0006] To achieve the above objectives, according to one aspect of the present invention, a light-reflecting film is provided, comprising:

[0007] The substrate layer has a first surface and a second surface disposed opposite to each other, and microstructures are disposed on the first surface;

[0008] A reflective layer is attached to the microstructure;

[0009] An adhesive layer is disposed on the outer surface of the substrate layer and covers the reflective layer;

[0010] The melting point of the substrate layer is less than 155℃.

[0011] Furthermore, the microstructure is selected from one or more of the following: prism structure, pyramid structure, and hemispherical structure.

[0012] Furthermore, along the thickness direction of the substrate layer, the height of the microstructure is less than 30 μm.

[0013] Furthermore, the microstructure is a prism structure, which has at least two light-reflecting planes. One of the at least two light-reflecting planes is arranged opposite to the other, and the extension direction of one of the at least two light-reflecting planes is set at a preset angle to the extension direction of the other. The preset angle is greater than 0 degrees and less than 180 degrees.

[0014] Furthermore, the ratio of the surface area of ​​the microstructure to the projected area of ​​the microstructure on the substrate layer is greater than or equal to 3 and less than or equal to 5.

[0015] Furthermore, the light transmittance of the substrate layer is greater than 91%.

[0016] Furthermore, the difference between the refractive index of the substrate layer and the refractive index of the adhesive layer is less than or equal to 0.05.

[0017] Furthermore, the substrate layer is made of maleic anhydride-grafted polyethylene or maleic anhydride-grafted polypropylene.

[0018] Furthermore, the thickness of the reflective layer is greater than or equal to 30 nm and less than or equal to 60 nm.

[0019] Furthermore, the reflective layer is made of metallic material.

[0020] According to another aspect of the present invention, a photovoltaic module is provided, comprising: the light-reflecting film provided above; the photovoltaic module further comprises:

[0021] The front panel, battery cells, and rear panel are arranged opposite each other and spaced apart, with the battery cells positioned between the front panel and the rear panel.

[0022] The light-reflecting film is disposed between the front panel and the plane where the solar cells are located, or between the rear panel and the plane where the solar cells are located.

[0023] Furthermore, the reflective layer of the light-reflecting film is located on the side of the substrate layer of the light-reflecting film away from the solar cell.

[0024] Furthermore, there are at least two battery cells, with a battery gap formed between two adjacent battery cells, and a front plate extending out of the at least two battery cells to form an edge gap between the ends of the at least two battery cells and the end of the front plate; wherein: the light-reflecting film is disposed opposite to the battery gap; and / or, the light-reflecting film is disposed opposite to the edge gap.

[0025] Furthermore, an adhesive layer is filled between the front and rear panels, and both the solar cells and the light-reflecting film are disposed within the adhesive layer. The material of the adhesive layer is the same as that of the adhesive layer of the light-reflecting film.

[0026] By applying the technical solution of this utility model, the melting point of the substrate layer is less than 155℃. This allows the substrate layer to melt during the lamination process of the photovoltaic module when the light-reflecting film is applied, thus forming a tighter bond with other structures of the photovoltaic module. This enhances the adhesion between the layers inside the module and avoids damage to the solar cells due to differences in hardness between the substrate and the film material. Furthermore, the reflective layer set on the microstructure reflects incident light, directing sunlight to the area surrounding the reflective film. When applied to a photovoltaic module, this guides sunlight incident on non-cell areas back to the cells, improving light utilization. Simultaneously, the close adhesion between the reflective layer and the microstructure improves the reflective performance of the film, further enhancing its ability to capture and redistribute light. The design of the reflective layer not directly contacting the solar cells avoids the risk of leakage in the photovoltaic module, significantly improving its safety. The adhesive layer not only facilitates the rapid application of the light-reflecting film to the components to be installed, but also provides additional protection for the microstructure. Simultaneously, it enhances the adhesion between the light-reflecting film and the adhesive film, improving the overall weather resistance of the photovoltaic module. Therefore, the technical solution of this invention effectively improves photoelectric conversion efficiency, ensures module safety, and effectively solves the technical problem of insufficient weather resistance in existing photovoltaic modules. Attached Figure Description

[0027] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an undue limitation of the present invention. In the drawings:

[0028] Figure 1 A schematic diagram of the structure of the light-reflecting film provided according to Embodiment 1 of the present invention is shown;

[0029] Figure 2 A schematic diagram of the structure of the light-reflecting film provided according to Embodiment 2 of the present invention is shown;

[0030] Figure 3 A schematic diagram of the structure of a photovoltaic module provided according to Embodiment 3 of the present invention is shown.

[0031] The above figures include the following reference numerals:

[0032] 1. Substrate layer; 11. Microstructure; 111. Light-reflecting plane; 12. Second surface;

[0033] 2. Reflective layer;

[0034] 3. Adhesive layer;

[0035] 4. Front panel;

[0036] 5. Battery cell; 51. Battery gap; 52. Edge gap;

[0037] 6. Back panel;

[0038] 71. Gap light reflective film; 711. First film segment; 712. Second film segment; 713. Third film segment; 72. Edge light reflective film; 721. Fourth film segment; 722. Fifth film segment;

[0039] 8. Adhesive layer. Detailed Implementation

[0040] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0041] like Figure 1 As shown, Embodiment 1 of this utility model provides a light-reflecting film, which includes a substrate layer 1, an adhesive layer 3, and a reflective layer 2. The substrate layer 1 has a first surface and a second surface 12 disposed opposite to each other, and a microstructure 11 is disposed on the first surface. The reflective layer 2 is attached to the microstructure 11. The adhesive layer 3 is disposed on the outer surface of the substrate layer 1 and covers the reflective layer 2. The melting point of the substrate layer 1 is less than 155°C.

[0042] The light-reflecting film provided in Embodiment 1 of this utility model has a substrate layer 1 with a melting point of less than 155°C. This allows the substrate layer 1 to melt during the lamination process of the photovoltaic module when the light-reflecting film is applied, thereby forming a tighter bond with other structures of the photovoltaic module and enhancing the adhesion between the layers inside the module. It also avoids damage to the photovoltaic module cells due to differences in hardness between the film and the substrate layer. Furthermore, the reflective layer 2 on the microstructure 11 reflects incident light, directing the incident sunlight to the area surrounding the light-reflecting film. When applied in a photovoltaic module, it guides sunlight incident on non-cell areas back to the cells, thereby improving light utilization. Simultaneously, the close fit between the reflective layer 2 and the microstructure 11 improves the reflective performance of the light-reflecting film, further enhancing its ability to capture and redistribute light. The design of the reflective layer 2 not directly contacting the cells further avoids the risk of leakage in the photovoltaic module, significantly improving its safety. The adhesive layer 3 not only facilitates the rapid installation of the light-reflecting film on the component to be installed, but also provides additional protection for the microstructure 11. Simultaneously, it enhances the adhesion between the light-reflecting film and the adhesive film, improving the overall weather resistance of the photovoltaic module. Therefore, the light-reflecting film provided in this embodiment can effectively improve photoelectric conversion efficiency, ensure the safety of the module, and effectively solve the technical problem of insufficient weather resistance in existing photovoltaic modules.

[0043] Specifically, light-reflecting films are used in photovoltaic modules.

[0044] Specifically, the microstructure 11 is selected from one or more of a prism structure, a pyramid structure, and a hemispherical structure. Thus, after attaching the reflective layer 2 to the microstructure 11, a specific reflective interface can be provided for the incident light, guiding the light in a specific direction. In photovoltaic modules, the design of the microstructure 11 allows light entering from the gaps between the cells to fall more effectively onto the surface of adjacent cells after a series of refractions and reflections, reducing light loss and thus improving the utilization rate of light energy. Prism structures, pyramid structures, and hemispherical structures can also increase the propagation path length of light inside the module. Through multiple reflections and refractions, the residence time of light in the module is increased, thereby improving the overall photoelectric conversion efficiency of the module. Among them, the pyramid structure has multi-faceted reflection characteristics, enabling light to be reflected on multiple surfaces, further dispersing and guiding light energy. Compared with the prism structure, the pyramid structure can capture and redirect incident light over a wider angle range. Especially under low-angle illumination conditions, the pyramid structure can more efficiently redirect light obliquely incident into the module to the cells, improving the power generation performance of the module under dawn / dusk, cloudy days, or low-light conditions. The hemispherical microstructure can create a lens-like effect, focusing incident light. In photovoltaic modules, the hemispherical structure can focus light incident from different angles onto the solar cells, especially at the gaps between cells, concentrating and guiding scattered light energy, thus improving the concentration of light energy and enhancing the module's photoelectric conversion efficiency. The microstructure 11 is selected from one or more combinations of prism, pyramid, and hemispherical structures. This integrated structural design can be customized according to the specific needs of the photovoltaic module and the installation environment to achieve optimal light energy utilization, helping to improve the light energy utilization rate and photoelectric conversion efficiency of the photovoltaic module, optimize the light distribution inside the module, while maintaining low production costs and good process compatibility.

[0045] Specifically, the microstructure 11 is a prism structure with at least two light-reflecting planes 111. One of the light-reflecting planes 111 is positioned opposite the other, and the extension direction of one of the light-reflecting planes 111 is at a predetermined angle to the extension direction of the other, with the predetermined angle being greater than 0 degrees and less than 180 degrees. This structural arrangement, through the design of at least two light-reflecting planes 111, allows light incident on the prism structure to be reflected multiple times. Even under low-angle or oblique illumination conditions, more light can be directed to the surface of the solar cell, improving the utilization rate of light energy. This design ensures that the module maintains high photoelectric conversion efficiency in all weather conditions and different geographical locations.

[0046] Specifically, the microstructure 11 has two light-reflecting planes 111, one of which is arranged along a predetermined direction to form a prism group. There are at least two prism groups, which are arranged sequentially along the predetermined direction. This structural arrangement, with multiple prism groups, allows for the processing of incident light from multiple directions, enhancing the light utilization rate of the light-reflecting film. It also maintains a high light-capturing effect, especially when the angle of sunlight incidence varies significantly.

[0047] Specifically, such as Figure 1 As shown, the microstructure 11 has two light-reflecting planes 111, one of which is connected to the other along a predetermined direction. The cross-section of the microstructure 11 is triangular along the length of the light-reflecting plane 111. This structural arrangement improves the compactness of the microstructure 11 and enhances the light utilization efficiency of the light-reflecting film.

[0048] Specifically, the angle between the extending direction of one of the two light-reflecting planes 111 and the extending direction of the substrate layer 1 is equal to the angle between the extending direction of the other of the two light-reflecting planes 111 and the extending direction of the substrate layer 1. This symmetrical angle design helps improve light reflectivity and directional control, avoids light deflection or loss during reflection, and ensures that more light can be effectively guided to the cell area, thereby improving the back-side power generation efficiency and overall power generation performance of the photovoltaic module.

[0049] Specifically, the angle between the extending direction of one of the two light-reflecting planes 111 and the extending direction of the substrate layer 1 is not equal to the angle between the extending direction of the other light-reflecting plane 111 and the extending direction of the substrate layer 1. This structural arrangement allows for more flexible guidance of light to the cell area, improving the module's light energy conversion efficiency under all-weather conditions. This design also optimizes the light reflection path for specific installation angles and environmental conditions, increasing the adaptability and functionality of the light-reflecting film.

[0050] Specifically, the microstructure 11 is a multi-faceted pyramidal structure with multiple sequentially connected light-reflecting planes 111. There are at least two pyramidal structures arranged sequentially along a predetermined direction. This structural arrangement provides a more complex light reflection path, enabling the capture and guidance of light from multiple directions, thus enhancing light scattering and redistribution. This type of light-reflecting film can more comprehensively improve the light utilization efficiency of non-cell areas of the photovoltaic module, especially when dealing with diffused light or low-incident-angle light. Simultaneously, the pyramidal structure helps to disperse and reduce localized photothermal effects, improving the long-term stability and durability of the module.

[0051] Specifically, the pyramidal structure can be a triangular pyramid or a square pyramid. A triangular pyramid refracts and reflects light through three faces, while a square pyramid provides four faces, increasing the complexity and flexibility of the optical path and enabling efficient light energy conversion under a wider range of lighting conditions.

[0052] Specifically, the preset angle is greater than or equal to 60 degrees and less than or equal to 150 degrees. For example... Figure 1 As shown, 60° ≤ a ≤ 150°. This preset angle design allows the light-reflecting film in the photovoltaic module to effectively refract and reflect incident light from multiple angles. The selection of the preset angle range ensures that the module can capture more light energy under different lighting conditions, thereby improving the overall light energy utilization and power generation efficiency of the module.

[0053] Specifically, the angle between the extending direction of one of the at least two light-reflecting planes 111 and the extending direction of the substrate layer 1 is greater than or equal to 30 degrees and less than or equal to 60 degrees; the angle between the extending direction of the other of the at least two light-reflecting planes 111 and the extending direction of the substrate layer 1 is greater than or equal to 30 degrees and less than or equal to 60 degrees. Figure 1 As shown, 30°≤b≤60°; 30°≤c≤60°. This angle design allows the light-reflecting plane 111 to achieve efficient and uniform light reflection, avoiding excessive concentration or dispersion of light during reflection, thus improving light energy conversion efficiency and component uniformity. It also helps reduce multiple reflections of light at material interfaces, lowering light energy loss and enhancing the overall performance of the component.

[0054] Specifically, b = 45°, c = 45°.

[0055] Specifically, microstructure 11 is selected from at least one of trapezoidal prism microstructure, pyramidal microstructure, and wedge-shaped prism microstructure. The trapezoidal prism microstructure is a prism shape with a base wider than its top surface, and its cross-section exhibits a trapezoidal profile. Specifically, one base of the trapezoidal prism is the surface of the light-reflecting film, while the other base is smaller and parallel to the first base, together forming the top surface of the prism. The sides consist of two mutually inclined planes, which connect to the top and bottom surfaces, forming the sidewalls of the trapezoidal prism. This allows for the capture of incident light from a wider angle range, and the light is refracted into the cell area of ​​the photovoltaic module through the tilting angle of the sides, improving light utilization. The pyramidal microstructure is a three-dimensional structure with a polygonal base and a converging top point. Typical shapes include square pyramids and triangular pyramids, with the base being a square, rectangle, or triangle, and the top a apex. This microstructure design allows incident light from different directions to be reflected multiple times and converged into a concentrated area, the base of the pyramid, before being guided through a light-reflecting film to the solar cell, thus improving the concentration and utilization of light on the cell. The wedge-shaped prism microstructure is a prism shape with one side of its base longer than the other. Its characteristic is that one side is wider than the opposite side, forming a wedge angle. The cross-section of the wedge prism exhibits a trapezoidal shape with one side longer than the other. This design allows incident light to be guided in a specific direction according to the wedge angle, effectively transforming light scattering in the gaps between the solar cells into directional reflection, thereby improving the incident light efficiency onto the solar cell.

[0056] Specifically, the microstructure 11 is formed by: casting on the first surface of the substrate layer 1 using a prism embossing roller; or by transferring the microstructure 11 onto the first surface of the substrate layer 1 using a sheet containing a prism structure; or by etching on the first surface; or by producing prism stripes using a stretching process. This choice of forming the microstructure 11 using a prism embossing roller or transferring it onto the first surface of the substrate layer 1 using a sheet containing a prism structure provides two efficient and cost-effective manufacturing methods. The casting process enables precise replication of the prism structure, ensuring consistency in the size and angle of each light-reflecting plane 111, thereby improving light reflection efficiency and directionality. The sheet transfer method simplifies the production process, reduces equipment investment, and increases production efficiency while ensuring the stability and reliability of the prism structure. The etching process allows for precise control of the shape, size, and distribution of the prisms, thereby highly optimizing the incident and reflection paths of light. The etching process typically achieves micron-level structural precision, ensuring the effectiveness and reliability of the light-reflecting film in the component. The stretching process typically provides good consistency and cost control in mass production. The resulting prism stripes can effectively guide incident light, allowing light energy to propagate along a predetermined path inside the module, increasing the contact area and time between light and the solar cell, thereby improving the light energy conversion efficiency.

[0057] Specifically, the second surface 12 has a planar structure. This structural arrangement, which keeps the second surface 12 planar, helps to improve flatness and reduce the difficulty of winding during the production of the light-reflecting film.

[0058] Specifically, in order to further improve the light reflection effect, a white coating is also provided on the microstructure 11 or the reflective layer 2.

[0059] Specifically, the reflectivity of reflective layer 2 is greater than 80%.

[0060] Specifically, the adhesive layer 3 is formed by coating the microstructure 11. This direct coating process ensures a tight bond between the adhesive layer 3 and the reflective layer 2, preventing the formation of air gaps and reducing light reflection losses at the interface. The coating process allows the molecules of the adhesive layer 3 to penetrate deep into the microscopic uneven surface of the microstructure 11, significantly reducing interface defects common in traditional lamination processes, such as bubbles, cracks, or insufficiently bonded areas. These defects are often the root cause of additional reflection losses when light propagates between layers. The direct coating process reduces light reflection losses at the interface by eliminating air gaps and improving interface smoothness, thereby improving the overall light transmittance and photoelectric conversion efficiency of the module. This deep bonding not only enhances the mechanical adhesion between the adhesive layer 3 and the reflective layer 2 but also improves the chemical compatibility between the two layers, ensuring long-term stability and reliability. The tight bond between the adhesive layer 3 and the reflective layer 2 helps improve the thermal performance and weather resistance of the photovoltaic module.

[0061] Specifically, the thickness of substrate layer 1 is less than 200 μm.

[0062] In this embodiment, the height of the microstructure 11 is less than 30 μm along the thickness direction of the substrate layer 1. For example... Figure 1 As shown, h < 30 μm. h is the height of microstructure 11. This helps to make the light-reflecting film thinner and lighter, and also helps to reduce the propagation path of light in the prism structure, reducing light absorption and scattering, thereby improving the light energy reflection efficiency.

[0063] Specifically, the ratio of the surface area of ​​the microstructure 11 to the projected area of ​​the microstructure 11 on the substrate layer 1 is greater than or equal to 3 and less than or equal to 5. This achieves both efficient light scattering and reflection without compromising mechanical properties during production, such as tear resistance and tensile strength, due to the excessive complexity of the microstructure 11. This design ensures the long-term stable operation of the light-reflecting film within the photovoltaic module and reduces performance degradation caused by structural changes.

[0064] Specifically, the light transmittance of the substrate layer 1 is greater than 91%. This ensures that light can efficiently pass through the substrate layer 1 and reach the light reflecting plane 111 and the reflective layer 2, minimizing light loss during propagation.

[0065] Specifically, the difference between the refractive index of the substrate layer 1 and the refractive index of the adhesive layer 3 is less than or equal to 0.05. This design avoids significant light refraction at the interface between different media, reduces light scattering and reflection losses, and improves light transmittance and guiding efficiency. The matching refractive indices also help reduce light absorption within the module, ensuring that more light can be effectively utilized by the solar cells, thereby improving the module's light energy conversion efficiency and power generation.

[0066] Specifically, the substrate layer 1 is made of any one of polyethylene, polypropylene and nylon.

[0067] Specifically, the substrate layer 1 is made of maleic anhydride-grafted polyethylene or maleic anhydride-grafted polypropylene. This structural arrangement improves the adhesion of the materials through maleic anhydride grafting, resulting in a stronger bond between the substrate layer 1 and the reflective layer 2. This enhances the structural stability of the light-reflecting film and its functional performance within the module. This modified material also exhibits excellent weather resistance and anti-aging properties, further extending the lifespan of the photovoltaic module.

[0068] In this embodiment, the thickness of the reflective layer 2 is greater than or equal to 30 nm and less than or equal to 60 nm. For example... Figure 1 As shown, 30nm ≤ d ≤ 60nm, where d is the thickness of reflective layer 2. This avoids the increased cost caused by excessive thickness and the decreased reflection efficiency caused by excessive thinness. Precise thickness control helps maintain the stability and reliability of reflective layer 2.

[0069] Specifically, the reflective layer 2 is made of a metallic material.

[0070] Specifically, the reflective layer 2 is made of gold, silver, aluminum, and related alloys.

[0071] Specifically, the reflective layer 2 is an aluminum coating. Aluminum is a highly reflective metal material that can effectively reflect incident light back to the cell area, significantly improving the module's light capture capability and power generation efficiency.

[0072] like Figure 1 As shown in Embodiment 1, the side of the adhesive layer 3 furthest from the reflective layer 2 has the same structure as the microstructure 11. This effectively reduces manufacturing costs and facilitates the distinction between the two sides of the light-reflecting film during photovoltaic module manufacturing, avoiding operational errors.

[0073] like Figure 2As shown, in Embodiment 2, the light-reflecting film includes a substrate layer 1, an adhesive layer 3, and a reflective layer 2. The substrate layer 1 has a first surface and a second surface 12 disposed opposite to each other, and a microstructure 11 is disposed on the first surface. The reflective layer 2 is attached to the microstructure 11. The adhesive layer 3 is disposed on the outer surface of the substrate layer 1 and covers the reflective layer 2. The difference between Embodiment 2 and Embodiment 1 is that in Embodiment 1, the side of the adhesive layer 3 away from the reflective layer 2 has the same structure as the microstructure 11, while in Embodiment 2, the side of the adhesive layer 3 away from the reflective layer 2 has a planar structure. In Embodiment 2, the planar structure of the adhesive layer 3 simplifies the surface shape of the adhesive layer and reduces the difficulty of winding during the production process of the light-reflecting film. When the planar adhesive layer 3 comes into contact with other structures of the photovoltaic module, it can provide a larger contact area and a more uniform pressure distribution, which helps to improve the bonding strength between the adhesive layer 3 and other structures of the photovoltaic module.

[0074] like Figure 3 As shown, Embodiment 3 of this utility model provides a photovoltaic module, which includes the light-reflecting film provided in Embodiment 1 or Embodiment 2. The photovoltaic module also includes a front panel 4, solar cells 5, and a rear panel 6. The front panel 4 and the rear panel 6 are arranged opposite each other and spaced apart, and the solar cells 5 are disposed between the front panel 4 and the rear panel 6. The light-reflecting film is disposed between the plane of the front panel 4 and the plane of the solar cells 5, or between the plane of the rear panel 6 and the plane of the solar cells 5.

[0075] The photovoltaic module provided in Embodiment 3 of this utility model, with the introduction of a light-reflecting film, especially its placement between the front panel 4 and the solar cells 5 or between the rear panel 6 and the solar cells 5, can significantly improve the photovoltaic module's efficiency in capturing and utilizing sunlight. The microstructure 11 and reflective layer 2 of the light-reflecting film can re-reflect and guide light incident on non-solar cell areas of the module back to the solar cell areas, reducing light energy loss, especially in the gap areas on the front or back of the module, which are typically considered areas of light energy waste. Furthermore, the melting point of the substrate layer 1 is less than 155°C, which allows the substrate layer 1 to melt at the temperature during the lamination process of the photovoltaic module when the light-reflecting film is applied, thereby forming a tighter bond with other structures of the photovoltaic module and enhancing the adhesion between the layers within the module. Therefore, the photovoltaic module provided in this embodiment can ensure the weather resistance of the photovoltaic module.

[0076] Specifically, when both the front panel 4 and the rear panel 6 are glass panels, the light-reflecting film is disposed between the front panel 4 and the solar cell 5, or between the rear panel 6 and the solar cell 5. When the front panel 4 is a glass panel and the rear panel 6 is a non-transparent panel, the light-reflecting film is disposed between the rear panel 6 and the solar cell 5.

[0077] like Figure 3 As shown, Figure 3The diagram illustrates the arrangement of the light-reflecting film between the rear panel 6 and the battery cell 5. The dashed lines and arrows in the diagram represent incident and reflected light rays.

[0078] Specifically, the reflective layer 2 of the light-reflecting film is located on the side of the substrate layer 1 of the light-reflecting film away from the solar cell 5. This structural arrangement ensures that the reflective layer 2 does not directly contact the solar cell 5, avoiding potential electrical conductivity risks. This is especially beneficial when the reflective layer 2 is made of a metallic material (such as aluminum), significantly improving the safety of the photovoltaic module. This layout also helps the reflective layer 2 efficiently reflect light incident from outside the module back to the solar cell area, reducing light scattering and absorption inside the module, improving light utilization efficiency, and thus enhancing the overall power generation performance of the photovoltaic module.

[0079] Specifically, there are at least two solar cells 5, which are spaced apart along the extension direction of the front panel 4 to form a gap 51 between adjacent solar cells 5. The front panel 4 extends beyond the at least two solar cells 5 to form an edge gap 52 between the ends of the at least two solar cells 5 and the end of the front panel 4. A light-reflecting film is positioned opposite to the solar cell gap 51. With this structural arrangement, the solar cell gap 51, which is traditionally a region with low light energy utilization in photovoltaic modules, can be re-reflected and guided onto adjacent solar cells 5 by placing a light-reflecting film at a relative position within the solar cell gap 51. This reduces light energy waste and significantly improves the photovoltaic module's efficiency in capturing and utilizing incident light.

[0080] Specifically, there are at least two solar cells 5, which are spaced apart along the extension direction of the front panel 4 to form a cell gap 51 between adjacent solar cells 5. The front panel 4 extends beyond the at least two solar cells 5 to form an edge gap 52 between the ends of the at least two solar cells 5 and the end of the front panel 4. A light-reflecting film is positioned opposite to the edge gap 52. This structural arrangement, with the light-reflecting film positioned opposite to the edge gap 52, effectively captures and redirects light entering the edge gap 52, converting this light energy into electrical energy. The optimized light utilization of the edge gap 52 further improves the overall light energy conversion efficiency of the module, especially in the edge region of the module, which often suffers from wasted light energy due to a lack of effective light-capturing mechanisms. Through the action of the light-reflecting film, the light energy utilization rate of the edge gap 52 is significantly improved, thus providing additional support for the high power output of the module.

[0081] Specifically, the light-reflecting film includes a gap light-reflecting film 71 and an edge light-reflecting film 72. Along the extending direction of the gap light-reflecting film 71, it has a first film segment 711, a second film segment 712, and a third film segment 713 connected in sequence. The first film segment 711 is positioned opposite to one of two adjacent solar cells 5, the second film segment 712 is positioned opposite to the gap 51 between the cells, and the third film segment 713 is positioned opposite to the other of the two adjacent solar cells 5. This structural arrangement expands the reflection area of ​​the gap light-reflecting film 71 through the first film segment 711 and the third film segment 713, improving its reflectivity and capturing more light from various incident angles, thereby enhancing the overall power generation efficiency of the module.

[0082] Specifically, the light-reflecting film includes a gap light-reflecting film 71 and an edge light-reflecting film 72. Along the extending direction of the edge light-reflecting film 72, the edge light-reflecting film 72 has a fourth film segment 721 and a fifth film segment 722 connected to each other. The fourth film segment 721 is disposed opposite to at least two solar cells 5, and the fifth film segment 722 is disposed opposite to the edge gap 52. This structural arrangement expands the reflection area of ​​the edge light-reflecting film 72 through the fourth film segment 721, improving the reflectivity of the edge light-reflecting film 72, capturing more light from various incident angles, and thus improving the overall power generation efficiency of the module.

[0083] Specifically, an adhesive layer 8 fills the space between the front panel 4 and the rear panel 6. The solar cells 5 and the light-reflecting film are both disposed within the adhesive layer 8, and the material of the adhesive layer 8 is the same as that of the adhesive layer 3 of the light-reflecting film. This ensures a tight bond between the light-reflecting film and other parts of the module (such as the solar cells 5, front panel 4, and rear panel 6), improving the structural stability and overall performance of the module. Material matching also helps reduce light energy loss at interfaces between different materials, improving light transmittance and reflection efficiency. Furthermore, the use of the same material simplifies the module's encapsulation process, reduces production costs, and enhances the module's weather resistance and long-term reliability, ensuring stable operation of the module in outdoor environments.

[0084] Specifically, the adhesive layer 8 and adhesive layer 3 are both made of EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), or other commonly used encapsulation materials for photovoltaic modules.

[0085] Specifically, the photovoltaic module is a frameless module on side A, and the edge sealing adhesive around the photovoltaic module is white adhesive, thereby enhancing the light reflection effect.

[0086] Specifically, using multiple light sources to simulate sunlight incidence, the light from the backsheet without a prism structure does not diverge, while the light from the backsheet with a prism structure diverges significantly. When light shines into the gaps between the solar cells, the light is diverged due to the prism structure, and the back of the solar cell also absorbs the light intensity reflected from the gaps, thereby improving the back-side power generation efficiency of the bifacial photovoltaic module.

[0087] As can be seen from the above description, the embodiments of this utility model achieve the following technical effects:

[0088] 1. By employing a light-reflecting film with an optimized prism structure and an aluminum-plated reflective layer in the gaps between modules, this solution can effectively capture and redirect light energy that is traditionally wasted in the gaps between cells and at the edges, thereby improving the power generation performance of the modules under different lighting conditions.

[0089] 2. The use of a low-melting-point substrate film allows it to melt during the lamination process of the photovoltaic module, improving the tighter bond with other structures of the photovoltaic module, enhancing the adhesion between the layers inside the module, improving the overall structural stability and long-term weather resistance of the photovoltaic module, and avoiding the risk of damaging the cells due to differences in hardness with other encapsulation materials.

[0090] 3. The flexible placement of the light-reflecting film allows the component to adapt to different installation environments and lighting conditions;

[0091] 4. There are no additional equipment investments or maintenance issues during production, and the equipment is highly compatible with customer equipment.

[0092] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0093] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0094] In the description of this application, it should be understood that the orientation or positional relationship indicated by directional terms such as "front, back, up, down, left, right", "horizontal, vertical, horizontal" and "top, bottom" is usually based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the scope of protection of this application; the directional terms "inner" and "outer" refer to the inner and outer contours relative to the outline of each component itself.

[0095] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0096] Furthermore, it should be noted that the use of terms such as "first" and "second" to define components is merely for the purpose of distinguishing the corresponding components. Unless otherwise stated, the above terms have no special meaning and therefore cannot be construed as limiting the scope of protection of this application.

[0097] The above description is merely a preferred embodiment of this utility model and is not intended to limit the utility model. Various modifications and variations can be made to this utility model by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the protection scope of this utility model.

Claims

1. A light-reflecting film, characterized in that, include: The substrate layer (1) has a first surface and a second surface (12) disposed opposite to each other, and microstructures (11) are disposed on the first surface; A reflective layer (2) is attached to the microstructure (11); An adhesive layer (3) is disposed on the outer surface of the substrate layer (1) and covers the reflective layer (2); The base material layer (1) has a melting point of less than 155°C.

2. The light-reflecting film according to claim 1, characterized in that, The microstructure (11) is selected from one or more of the following: prism structure, pyramid structure, and hemispherical structure; and / or, Along the thickness direction of the substrate layer (1), the height of the microstructure (11) is less than 30 μm.

3. The light-reflecting film according to claim 1, characterized in that, The microstructure (11) is a prism structure, which has at least two light-reflecting planes (111). One of the at least two light-reflecting planes (111) is arranged opposite to the other. The extension direction of one of the at least two light-reflecting planes (111) is set at a preset angle to the extension direction of the other. The preset angle is greater than 0 degrees and less than 180 degrees.

4. The light-reflecting film according to claim 1, characterized in that, The ratio of the surface area of ​​the microstructure (11) to the projected area of ​​the microstructure (11) on the substrate layer (1) is greater than or equal to 3 and less than or equal to 5.

5. The light-reflecting film according to claim 1, characterized in that, The light transmittance of the substrate layer (1) is greater than 91%; and / or, The difference between the refractive index of the substrate layer (1) and the refractive index of the adhesive layer (3) is less than or equal to 0.05; and / or, The substrate layer (1) is made of maleic anhydride-grafted polyethylene or maleic anhydride-grafted polypropylene.

6. The light-reflecting film according to claim 1, characterized in that, The thickness of the reflective layer (2) is greater than or equal to 30 nm and less than or equal to 60 nm; and / or, The reflective layer (2) is made of metallic material.

7. A photovoltaic module, characterized in that, include: The light-reflecting film according to any one of claims 1 to 6; The photovoltaic module also includes: A front panel (4), a battery cell (5), and a rear panel (6) are provided, wherein the front panel (4) and the rear panel (6) are arranged opposite to each other and spaced apart, and the battery cell (5) is disposed between the front panel (4) and the rear panel (6); The light-reflecting film is disposed between the plane of the front plate (4) and the plane of the battery cell (5) or between the plane of the rear plate (6) and the plane of the battery cell (5).

8. The photovoltaic module according to claim 7, characterized in that, The reflective layer (2) of the light-reflecting film is located on the side of the substrate layer (1) of the light-reflecting film away from the battery cell (5).

9. The photovoltaic module according to claim 7, characterized in that, The battery cells (5) are at least two, with a battery gap (51) formed between two adjacent battery cells (5). The front plate (4) extends beyond the at least two battery cells (5) to form an edge gap (52) between the ends of the at least two battery cells (5) and the end of the front plate (4); wherein: The light-reflecting film is disposed opposite to the battery gap (51); and / or, The light-reflecting film is disposed opposite to the edge gap (52).

10. The photovoltaic module according to claim 7, characterized in that, An adhesive layer (8) is filled between the front plate (4) and the rear plate (6). The battery cell (5) and the light-reflecting film are both disposed in the adhesive layer (8). The material of the adhesive layer (8) is the same as that of the adhesive layer (3) of the light-reflecting film.

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