Double-sided reflective gap film and bifacial photovoltaic module

Abstract

A double-sided reflective gap film and a bifacial photovoltaic module provided with the double-sided reflective gap film. The double-sided reflective gap film comprises: a rear adhesive layer (01521), a middle support layer (01522), a front reflective structure (01523), and a rear reflective structure (01525). The front reflective structure (01523) is arranged on one side of the middle support layer (01522) and comprises a plurality of inverted V-shaped tooth members arranged side by side, and the front reflective structure (01523) is coated with a front reflective layer (01524). The rear reflective structure (01525) is arranged on the other side of the middle support layer (01522). The thickness of the rear adhesive layer (01521) is not less than the height of the rear reflective structure (01525), so that the rear reflective structure (01525) is completely within the rear adhesive layer (01521).

Description

Double-sided reflective gap film and double-sided photovoltaic module

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to a Chinese patent application filed with the State Intellectual Property Office on February 26, 2024, with application number 202420351969.2 and invention name “Double-Sided Reflective Gap Film and Double-Sided Photovoltaic Module”, the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The embodiments of the present disclosure relate to, but are not limited to, the field of photovoltaic power generation, and in particular, to a double-sided reflective gap film and a double-sided photovoltaic module having the double-sided reflective gap film. Background Art

[0004] Solar photovoltaic power generation is a technology that uses the photovoltaic effect at the interface of semiconductors to directly convert light energy into electrical energy. As the sustainable development of human economy and society places increasingly stringent requirements on energy and environmental protection, this power generation method is gaining more and more attention.

[0005] Current photovoltaic modules are primarily divided into single-sided and bifacial modules. Bifacial modules typically consist of a front panel (photovoltaic glass), a transparent front-side encapsulating film, photovoltaic cells, a transparent back-side encapsulating film, and a back panel (transparent backsheet or glass). Currently, it's difficult to manufacture photovoltaic cells that are oversized. Therefore, photovoltaic modules typically utilize multiple photovoltaic cells arranged side by side. However, gaps between these cells can affect power generation efficiency.

[0006] How to further improve the utilization rate of sunlight by photovoltaic cell units and increase the output power of photovoltaic modules has always been a problem that technicians have been constantly exploring and trying to solve. Summary of the Invention

[0007] One objective of the present disclosure is to provide a double-sided reflective gap film, which is applied to a double-sided photovoltaic module and is aligned with the gap between two adjacent double-sided photovoltaic cell units of the double-sided photovoltaic module. The double-sided reflective gap film includes: a back adhesive layer, an intermediate support layer, a front reflective structure, and a back reflective structure. The front reflective structure is disposed on one side of the intermediate support layer and includes a plurality of ∧-shaped toothed members arranged side by side. The front reflective structure is coated with the front reflective layer. The back reflective structure is disposed on the other side of the intermediate support layer. The thickness of the back adhesive layer is not less than the height of the back reflective structure, so that the back reflective structure is located within the back adhesive layer.

[0008] Another object of the present disclosure is to provide a double-sided photovoltaic module, which includes: a photovoltaic glass front panel, a front transparent encapsulation film, a back transparent encapsulation film, a transparent back panel or a glass back panel, a double-sided reflective gap film and a plurality of double-sided photovoltaic cell units, wherein the double-sided reflective gap film is a double-sided reflective gap film according to an embodiment of the present disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG1 is a schematic diagram of a photovoltaic module according to an embodiment of the present disclosure.

[0010] FIG2 is a schematic diagram of a reflective gap film according to an embodiment of the present disclosure.

[0011] FIG3 is a schematic diagram of a bifacial photovoltaic module according to an embodiment of the present disclosure.

[0012] FIG4 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0013] FIG5 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0014] FIG6 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0015] FIG. 7 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0016] FIG8 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0017] FIG. 9 is a schematic diagram of a surface-insulating reflective gap film according to an embodiment of the present disclosure.

[0018] FIG10 is a schematic diagram of a double-sided reflective gap film with surface insulation according to an embodiment of the present disclosure.

[0019] FIG. 11 is a schematic diagram of a surface-insulated double-sided reflective gap film according to an embodiment of the present disclosure.

[0020] FIG12 is a schematic diagram of a surface-insulated double-sided reflective gap film according to an embodiment of the present disclosure.

[0021] FIG13 is a schematic diagram of a surface-insulated double-sided reflective gap film according to an embodiment of the present disclosure.

[0022] FIG14 is a schematic plan view of a photovoltaic module according to an embodiment of the present disclosure.

[0023] FIG15 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure.

[0024] 16 is a schematic diagram of a double-sided reflective gap film with a metal coating according to one embodiment of the present disclosure. DETAILED DESCRIPTION

[0025] To enable those skilled in the art to better understand the technical solution of the present disclosure, the double-sided reflective gap film and the double-sided photovoltaic module having the double-sided reflective gap film provided by the present disclosure are described in detail below with reference to the accompanying drawings.

[0026] Example embodiments will be described more fully hereinafter with reference to the accompanying drawings, but the example embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the scope of this disclosure to those skilled in the art.

[0027] In the absence of conflict, the various embodiments of the present disclosure and the various features therein may be combined with each other.

[0028] As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0029] The terms used herein are used only to describe specific embodiments and are not intended to limit the present disclosure. As used herein, the singular forms "a," "an," and "the" are also intended to include the plural forms, unless the context clearly indicates otherwise. It will also be understood that when the terms "comprising" and / or "made of" are used in this specification, the presence of the features, wholes, steps, operations, elements, and / or components is specified, but the presence or addition of one or more other features, wholes, steps, operations, elements, components, and / or groups thereof is not excluded.

[0030] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant art and the present disclosure, and will not be interpreted as having an idealized or overly formal meaning unless expressly defined as such herein.

[0031] To help those skilled in the art better understand the technical solutions of the present disclosure, exemplary embodiments will be described in detail below. When the following description refers to the accompanying drawings, unless otherwise indicated, identical numbers in different drawings represent identical or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples consistent with certain aspects of the present disclosure, as detailed in the appended claims.

[0032] FIG1 is a schematic diagram of a photovoltaic module according to an embodiment of the present disclosure. As shown in FIG1 , the photovoltaic module according to the present disclosure includes: a photovoltaic glass front panel 011, a front transparent encapsulating film 012, a back transparent encapsulating film 013, a transparent back panel or glass rear panel 014, a reflective gap film 015, and a plurality of bifacial photovoltaic cell units 016. The photovoltaic glass front panel 011 is positioned closely above the front transparent encapsulating film 012 to protect it. The transparent back panel or glass rear panel 014 is positioned closely below the back transparent encapsulating film 013 to protect it. The plurality of bifacial photovoltaic cell units 016 are positioned side by side between the front transparent encapsulating film 012 and the back transparent encapsulating film 013. The reflective gap film 015 is positioned within the back transparent encapsulating film 013, positioned above the transparent back panel or glass rear panel 014, and aligned with the gap between two adjacent bifacial photovoltaic cell units 016. The photovoltaic glass front plate 011, the front transparent packaging film 012, the back transparent packaging film 013, the transparent back plate or glass back plate 014, the reflective gap film 015 and the multiple double-sided photovoltaic cell units 016 are packaged into a photovoltaic module after the photovoltaic cell units are welded, the gap film is applied, and the layers are laminated.

[0033] By installing reflective film in the gap between adjacent bifacial photovoltaic cells 016, sunlight can be reflected back into the cells for reuse, thereby increasing the output power and power generation of the photovoltaic module. This is an effective way to increase the efficiency of photovoltaic modules. This type of photovoltaic power generation module is mainly suitable for use in scenarios such as ground-based power stations.

[0034] Figure 2 is a schematic diagram of a reflective gap film according to one embodiment of the present disclosure. As shown in Figure 2, the gap reflective film 015 comprises an intermediate support layer 01512, a backside adhesive layer 01511, a frontside reflective structure 01513, and a reflective layer 01514. The intermediate support layer 01512 is typically a relatively flat PET substrate, while the backside adhesive layer 01511 utilizes an adhesive layer for bonding to a transparent backplane or glass rear panel 014. This reflective gap film utilizes multiple frontside reflective structures and reflective layers to recycle sunlight.

[0035] To improve the utilization of backside sunlight and scattered light, the entire or a portion of the backside adhesive layer 01511 can be made into a reflective layer, for example, a reflective layer containing titanium dioxide or the like, to serve as a backside reflective structure. Alternatively, the backside adhesive layer 01511 can include a multiple-layer structure, for example, a transparent sublayer-reflective sublayer-transparent sublayer. The transparent sublayer serves to bond the different materials and provide flexibility and fluidity, while the reflective sublayer provides reflection. The backside adhesive layer 01511 can be made of EVA, POE polymer resin, or a composite resin. Preferably, the backside adhesive layer 01511 is made of cross-linked EVA or POE with a crosslinking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The crosslinking degree can be adjusted as needed. For example, the crosslinking degree can depend on the specific formulation, lamination parameters, and testing methods. The backside reflective structure can be a material formed by doping the EVA, POE polymer resin, or composite resin with at least one of titanium dioxide, zirconium oxide, barium sulfate, or aluminum hydroxide.

[0036] In order to improve the utilization rate of backside sunlight and scattered light, the embodiments of the present disclosure provide a double-sided photovoltaic module and a double-sided reflective gap film.

[0037] Figure 3 is a schematic diagram of a bifacial photovoltaic module according to one embodiment of the present disclosure. As shown in Figure 3, the bifacial photovoltaic module according to the present disclosure includes: a photovoltaic glass front panel 011, a front transparent encapsulating film 012, a back transparent encapsulating film 013, a transparent back panel or glass rear panel 014, a bifacial reflective gap film 0152, and a plurality of bifacial photovoltaic cell units 016. The photovoltaic glass front panel 011 is positioned closely above the front transparent encapsulating film 012 to protect it. The transparent back panel or glass rear panel 014 is positioned closely below the back transparent encapsulating film 013 to protect it. The plurality of bifacial photovoltaic cell units 016 are positioned side by side between the front transparent encapsulating film 012 and the back transparent encapsulating film 013. The bifacial reflective gap film 0152 is positioned within the back transparent encapsulating film 013, positioned above the transparent back panel or glass rear panel 014, and aligned with the gap between adjacent bifacial photovoltaic cell units 016.

[0038] FIG4 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure. As shown in FIG4 , the double-sided reflective gap film 0152 includes a backside adhesive layer 01521, an intermediate support layer 01522, a front side reflective structure 01523, and a back side reflective structure 01525. The intermediate support layer 01522 is made of, for example, PET and has a thickness of 10 to 100 μm. The front side reflective structure 01523 is disposed on one side surface (the upper surface in FIG4 ) of the intermediate support layer 01522 and includes several ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded using UV-curable adhesive and has an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back side reflective structure 01525 is disposed on the other side surface (the lower surface in FIG4 ) of the intermediate support layer 01522 and includes several ∨-shaped tooth-shaped members arranged side by side. Each ∨-shaped toothed member can be molded with UV curable adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The thickness of the back adhesive layer 01521 is no less than the height of the back reflective structure 01525, so that the back reflective structure 01525 is located or completely located within the back adhesive layer 01521.

[0039] A front reflective layer 01524 is coated on the front reflective structure 01523. The front reflective layer 01524 can be an aluminum layer formed by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. Similarly, the back reflective structure 01525 includes a back reflective layer 01526 coated thereon. The back reflective layer 01526 can be an aluminum layer formed by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm.

[0040] The back adhesive layer 01521 can be made of a polymer resin or composite resin such as EVA, POE, or PVB, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 01521 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer 01521 is used to bond to the transparent backplane or glass backplane 014 of the bifacial photovoltaic module.

[0041] The manufacturing process of the double-sided photovoltaic module and the double-sided reflective gap film provided in this embodiment may include: forming a UV-curing adhesive molding structure with a reflective structure on the surface of the support layer resin by mold transfer, screen printing, etc.; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, etc.; compounding the adhesive layer and the above structure into a whole by using cast lamination, film pasting, glue coating, etc.; applying the adhesive layer of the double-sided reflective gap reflective film to the back plate by heating; and then, welding, stacking, and laminating the solar cells according to the photovoltaic module structure to produce a double-sided photovoltaic module for power generation.

[0042] In order to improve the utilization rate of backside sunlight and scattered light, the embodiments of the present disclosure further provide a double-sided photovoltaic module and a double-sided reflective gap film.

[0043] Figure 5 is a schematic diagram of a bifacial photovoltaic module according to one embodiment of the present disclosure. As shown in Figure 5, the bifacial photovoltaic module according to the present disclosure includes: a photovoltaic glass front panel 011, a front transparent encapsulating film 012, a back transparent encapsulating film 013, a transparent back panel or glass rear panel 014, a bifacial reflective gap film 0153, and a plurality of bifacial photovoltaic cell units 016. The photovoltaic glass front panel 011 is positioned closely above the front transparent encapsulating film 012 to protect it. The transparent back panel or glass rear panel 014 is positioned closely below the back transparent encapsulating film 013 to protect it. The plurality of bifacial photovoltaic cell units 016 are positioned side by side between the front transparent encapsulating film 012 and the back transparent encapsulating film 013. The bifacial reflective gap film 0153 is positioned within the back transparent encapsulating film 013, positioned above the transparent back panel or glass rear panel 014, and aligned with the gap between adjacent bifacial photovoltaic cell units 016.

[0044] FIG6 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure. As shown in FIG6 , the double-sided reflective gap film 0153 includes: a back adhesive layer 01531, an intermediate support layer 01532, a front reflective structure 01533, and a back reflective structure 01535. The intermediate support layer 01532 is made of, for example, PET and has a thickness of 10 to 100 μm. The front reflective structure 01533 is disposed on one side surface (the upper surface in FIG6 ) of the intermediate support layer 01532 and includes a plurality of ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded with UV-curable adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back reflective structure 01535 is disposed on the other side surface (the lower surface in FIG6 ) of the intermediate support layer 01532. The thickness of the back adhesive layer 01531 is not less than the height of the back reflective structure 01535 , so that the back reflective structure 01525 is located or completely located within the back adhesive layer 01531 .

[0045] A front reflective layer 01534 is coated on the front reflective structure 01533. The front reflective layer 01534 can be an aluminum layer formed by vacuum deposition, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. As shown in FIG6 , the back reflective structure 01535 comprises tightly packed spherical particles made of at least one of titanium dioxide, zirconium oxide, barium sulfate, aluminum hydroxide, and the like, forming a reflective coating.

[0046] The back adhesive layer 01531 can be made of a polymer resin or composite resin such as EVA, POE, or PVB, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 01531 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0047] The manufacturing process of the double-sided photovoltaic module and the double-sided reflective gap film provided in this embodiment may include: forming a UV-curing adhesive molding structure with a reflective structure on the front side of the supporting layer resin by mold transfer, screen printing, etc.; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, etc.; coating or spraying a reflective coating on the back side and drying it; using cast lamination, film pasting, glue coating, etc. to composite the adhesive layer and the back reflective coating into a whole; applying the adhesive layer of the double-sided reflective gap reflective film to the back panel by heating; and welding, stacking, and laminating solar cells according to the photovoltaic module structure to produce a double-sided photovoltaic module for power generation.

[0048] In order to improve the utilization rate of backside sunlight and scattered light, the embodiments of the present disclosure further provide a double-sided photovoltaic module and a double-sided reflective gap film.

[0049] Figure 7 is a schematic diagram of a bifacial photovoltaic module according to one embodiment of the present disclosure. As shown in Figure 7, the bifacial photovoltaic module according to the present disclosure includes: a photovoltaic glass front panel 011, a front transparent encapsulating film 012, a back transparent encapsulating film 013, a transparent back panel or glass rear panel 014, a bifacial reflective gap film 0154, and a plurality of bifacial photovoltaic cell units 016. The photovoltaic glass front panel 011 is positioned closely above the front transparent encapsulating film 012 to protect it. The transparent back panel or glass rear panel 014 is positioned closely below the back transparent encapsulating film 013 to protect it. The plurality of bifacial photovoltaic cell units 016 are positioned side by side between the front transparent encapsulating film 012 and the back transparent encapsulating film 013. The bifacial reflective gap film 0154 is positioned within the back transparent encapsulating film 013, positioned above the transparent back panel or glass rear panel 014, and aligned with the gap between adjacent bifacial photovoltaic cell units 016.

[0050] FIG8 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure. As shown in FIG8 , the double-sided reflective gap film 0154 includes: a back adhesive layer 01541, an intermediate support layer 01542, a front reflective structure 01543, and a back reflective structure 01545. The intermediate support layer 01542 is made of, for example, PET and has a thickness of 10 to 100 μm. The front reflective structure 01543 is disposed on one side surface (the upper surface in FIG8 ) of the intermediate support layer 01542 and includes a plurality of ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded with UV-curable adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back reflective structure 01545 is disposed on the other side surface (the lower surface in FIG8 ) of the intermediate support layer 01542. The thickness of the back adhesive layer 01541 is not less than the height of the back reflective structure 01545 , so that the back reflective structure 01545 is located or completely located within the back adhesive layer 01541 .

[0051] A front reflective layer 01544 is coated on the front reflective structure 01543. The front reflective layer 01544 can be an aluminum layer formed by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. The back reflective structure 01545 is an aluminum layer formed on the other side of the intermediate support layer 01542 by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm.

[0052] The back adhesive layer 01541 can be made of a polymer resin such as EVA, POE, or a composite of two resins, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 01541 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0053] The manufacturing process of the double-sided photovoltaic module and the double-sided reflective gap film provided in this embodiment may include: forming a UV-curing adhesive molding structure with a reflective structure on the front side of the supporting layer resin by mold transfer, screen printing, etc.; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, etc.; forming an aluminum layer on the back side of the supporting layer resin by vacuum aluminum plating, sputtering, etc.; compounding the adhesive layer and the back reflective coating into a whole by using cast lamination, film pasting, glue coating, etc.; applying the adhesive layer of the double-sided reflective gap reflective film to the back plate by heating; and welding, stacking, and laminating solar cells according to the photovoltaic module structure to produce a double-sided photovoltaic module for power generation.

[0054] As described above, with the exception of the double-sided reflective gap film of the embodiment shown in FIG2 , the double-sided reflective gap films of the embodiments shown in FIG4 , FIG6 , and FIG8 all have a backside reflective structure. Table 1 below provides a detailed comparison of the double-sided reflective gap film of the embodiment shown in FIG2 with the double-sided reflective gap films of the embodiments shown in FIG4 , FIG6 , and FIG8 .

[0055] Table 1:

[0056] It can be seen that the use of the double-sided photovoltaic modules and double-sided reflective gap films provided by the embodiments of the present disclosure can maximize the output power and power generation effect on the back of the double-sided photovoltaic modules while ensuring the improved power generation on the front of the double-sided cell photovoltaic modules, and can increase the output power on the back of the photovoltaic modules by 0.2%-3%. In addition, a back-reflective structure is provided on the back of the double-sided reflective gap film, so that the middle support layer can be better protected, thereby improving the reliability of the double-sided reflective gap film. The double-sided photovoltaic modules and double-sided reflective gap films provided by the embodiments of the present disclosure have good long-term reliability and process feasibility, which are of positive significance for improving the power generation efficiency of photovoltaic modules and reducing the levelized cost of energy (LCOE) of photovoltaic power stations.

[0057] As mentioned above, the reflective layer of the reflective gap film typically utilizes a UV-cured front-side reflective structure or aluminized materials. These materials are susceptible to surface abrasion during the film winding, unwinding, packaging, and transportation of the reflective gap film. Furthermore, during the lamination process of PV modules, the tin-coated interconnecting ribbons between the cells may produce tin slag, tin beads, and uneven burrs, which can cause punctures in the encapsulation film. Once the film is damaged, the insulation distance between the interconnecting ribbons and the reflective gap film is reduced, which can cause localized leakage, thereby reducing the output power of the PV module and potentially causing reliability issues.

[0058] To address this issue, the insulation distance can be increased by increasing the thickness of the transparent encapsulation film on the back. However, this approach increases the material cost of the encapsulation film, which is not conducive to reducing the overall cost and improving the efficiency of photovoltaic modules.

[0059] Based on the above problems, the present disclosure also proposes a double-sided reflective gap film with surface insulation, which can effectively reduce the surface wear of the film strip during winding, unwinding, packaging and transportation, thereby extending the service life. Due to the use of a double-sided reflective material with surface insulation properties, even when the thickness of the transparent packaging film on the back of the photovoltaic module is reduced, the insulation distance between the tin-coated interconnection solder strip and the gap film in the gap between the battery cells can be avoided from being shortened during the lamination process, thereby reducing the risk of local leakage and enhancing the stability and reliability of the photovoltaic module. In addition, this surface-insulated double-sided reflective gap film does not affect the reflective efficiency of the film strip of the reflective gap film while maintaining the overall structure unchanged, thereby ensuring the output power and back double-sidedness of the photovoltaic module, and improving the reliability of the module. Due to the insulating properties of the surface material of the gap film, the film strip of the reflective gap film can also be extended to the four sides of the photovoltaic module, thereby further improving the overall performance of the module and reducing costs.

[0060] Figure 9 is a schematic diagram of a surface-insulating reflective gap film according to one embodiment of the present disclosure. As shown in Figure 9, the surface-insulating gap reflective film 0251 includes an intermediate support layer 02512, a backside adhesive layer 02511, a front reflective structure 02513, a reflective layer 02514, and a surface insulating layer 02517. The intermediate support layer 02512 is typically a relatively flat PET substrate, while the backside adhesive layer 02511 utilizes an adhesive layer for bonding to a transparent backplane or glass rear panel 014.

[0061] The surface insulation layer 02517 is made of polymer resins such as EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), PVB (polyvinyl butyral), or a composite of two or more of these resins. These resin materials, due to their low fluidity, can ensure the formation of a uniform and flat surface during processing. In order to further improve the performance of the surface insulation layer 02527, polymer particles with a low melt index can be selected, which helps to maintain the stability and consistency of the film during the film formation process. In addition, after film formation, the mechanical properties and chemical stability of the surface insulation layer can be enhanced by electron radiation cross-linking or thermal cross-linking treatment to ensure that it maintains good insulation properties under various environmental conditions. The surface insulation layer can completely cover the surface of the reflective layer, forming a relatively flat protective layer with good insulation properties. This design not only improves the reliability and durability of photovoltaic modules, but also helps to reduce production costs and achieve more efficient energy conversion.

[0062] Figure 10 is a schematic diagram of a surface-insulated, double-sided reflective gap film according to an embodiment of the present disclosure. As shown in Figure 10, the surface-insulated, double-sided reflective gap film 0252 includes a backside adhesive layer 02521, an intermediate support layer 02522, a front side reflective structure 02523, and a back side reflective structure 02525. The intermediate support layer 02522 is made of, for example, PET and has a thickness of 10 to 100 μm. The front side reflective structure 03523 is disposed on one side of the intermediate support layer 02522 (the upper side in Figure 10) and includes several ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded using UV-curable adhesive and has an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back side reflective structure 02525 is disposed on the other side of the intermediate support layer 02522 (the lower side in Figure 10) and includes several ∨-shaped tooth-shaped members arranged side by side. Each ∨-shaped toothed member can be molded with UV curing adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The thickness of the back adhesive layer 02521 is not less than the height of the back reflective structure 02525, so that the back reflective structure 02525 is located or completely located within the back adhesive layer 02521. A front reflective layer 02524 is coated on the front reflective structure 02523. The front reflective layer 02524 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. Similarly, the back reflective structure 02525 includes a back reflective layer 02526 coated on the back reflective structure. The back reflective layer 02526 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. The back adhesive layer 02521 can be made of a polymer resin such as EVA, POE, or a composite resin thereof, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 02521 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0063] A surface insulating layer 02527 is also provided on the front reflective layer 02524 of the front reflective structure 02523, so that the surface insulating layer 02527 covers the surface of the front reflective layer 02524. The surface insulating layer 02527 has a relatively flat surface. The surface insulating layer 02527 is made of polymer resins such as EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), PVB (polyvinyl butyral), or two or more composite forms of these resins. These resin materials, due to their low fluidity, can ensure the formation of a uniform and flat surface during the processing process. In order to further improve the performance of the surface insulating layer 02527, polymer particles with a low melt index can be selected, which helps to maintain the stability and consistency of the film during the film forming process.

[0064] The manufacturing process of a double-sided photovoltaic module with a surface-insulating double-sided reflective gap film provided in accordance with this embodiment may include: forming a UV-curable adhesive molding structure with a reflective structure on the surface of a support layer resin by mold transfer, screen printing, or the like; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, or the like; combining an adhesive layer with the above-mentioned structure into a whole by using cast lamination, film lamination, or glue coating; combining a surface insulating layer with the surface of a reflective layer into a whole by using cast lamination, film lamination, or glue coating, and subjecting the surface insulating layer to electron irradiation or thermal cross-linking treatment to reduce its fluidity; applying the adhesive layer of the double-sided reflective gap reflective film to a back panel by heating; and then, during packaging, a thinner photovoltaic module backside packaging film may be used, and solar cells may be welded, stacked, and laminated according to the photovoltaic module structure to produce a double-sided photovoltaic module.

[0065] FIG11 is a schematic diagram of a surface-insulated, double-sided reflective gap film according to an embodiment of the present disclosure. As shown in FIG11 , the double-sided reflective gap film 0253 includes a backside adhesive layer 02531, an intermediate support layer 02532, a front side reflective structure 02533, and a back side reflective structure 02535. The intermediate support layer 02532 is made, for example, of PET and has a thickness of 10 to 100 μm. The front side reflective structure 02533 is disposed on one side surface (the upper side in FIG11 ) of the intermediate support layer 02532 and includes a plurality of ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded with UV-curable adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back side reflective structure 02535 is disposed on the other side surface (the lower side in FIG11 ) of the intermediate support layer 02532. The thickness of the back adhesive layer 02531 is no less than the height of the back reflective structure 02535, such that the back reflective structure 02525 is located or completely located within the back adhesive layer 02531. A front reflective layer 02534 is coated on the front reflective structure 02533. The front reflective layer 02534 can be an aluminum layer formed by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. As shown in FIG11 , the back reflective structure 02535 comprises tightly packed spherical particles made of at least one of titanium dioxide, zirconium oxide, barium sulfate, aluminum hydroxide, and the like, forming a reflective coating. The back adhesive layer 02531 can be made of a polymer resin or composite resin such as EVA or POE, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 02531 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0066] A surface insulating layer 02537 is also provided on the front reflective layer 02534 of the front reflective structure 02533, so that the surface insulating layer 02537 covers the surface of the front reflective layer 02534. The surface insulating layer 02537 has a relatively flat surface. The surface insulating layer 02537 is made of polymer resins such as EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), PVB (polyvinyl butyral), or two or more composite forms of these resins. These resin materials can ensure the formation of a uniform and flat surface during the processing due to their low fluidity. In order to further improve the performance of the surface insulating layer 02537, polymer particles with a lower melt index can be selected, which helps to maintain the stability and consistency of the film during the film forming process.

[0067] The manufacturing process of a double-sided photovoltaic module with a surface-insulating double-sided reflective gap film provided in accordance with this embodiment may include: forming a UV-curable adhesive molding structure with a reflective structure on the front side of a supporting layer resin by mold transfer, screen printing, or the like; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, or the like; coating or spraying a reflective coating on the back side and drying it; composite the adhesive layer and the back reflective coating into a whole by using cast lamination, film lamination, or glue coating; composite the surface insulating layer and the reflective layer surface into a whole by using cast lamination, film lamination, or glue coating, and subjecting the surface insulating layer to electron irradiation or thermal cross-linking treatment to reduce its fluidity; applying the adhesive layer of the double-sided reflective gap reflective film to a back panel by heating; during packaging, a thinner photovoltaic module backside packaging film may be used, and solar cells may be welded, stacked, and laminated according to the photovoltaic module structure to produce a double-sided photovoltaic module.

[0068] FIG12 is a schematic diagram of a surface-insulated, double-sided reflective gap film according to an embodiment of the present disclosure. As shown in FIG12 , the double-sided reflective gap film 0254 includes: a backside adhesive layer 02541, an intermediate support layer 02542, a front side reflective structure 02543, and a back side reflective structure 02545. The intermediate support layer 02542 is made of, for example, PET and has a thickness of 10 to 100 μm. The front side reflective structure 02543 is disposed on one side surface (the upper surface in FIG12 ) of the intermediate support layer 02542 and includes a plurality of ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded with UV-curable adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back side reflective structure 02545 is disposed on the other side surface (the lower surface in FIG12 ) of the intermediate support layer 02542. The thickness of the back adhesive layer 02541 is no less than the height of the back reflective structure 02545, such that the back reflective structure 02545 is located or completely located within the back adhesive layer 02541. A front reflective layer 02544 is coated on the front reflective structure 02543. The front reflective layer 02544 can be an aluminum layer formed by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. The back reflective structure 02545 is an aluminum layer formed on the other surface of the intermediate support layer 02542 by vacuum aluminum plating, sputtering, or the like, with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. The back adhesive layer 02541 can be made of a polymer resin such as EVA, POE, or a composite of two resins, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 02541 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0069] A surface insulating layer 02547 is also provided on the front reflective layer 02544 of the front reflective structure 02543, so that the surface insulating layer 02547 covers the surface of the front reflective layer 02544. The surface insulating layer 02547 has a relatively flat surface. The surface insulating layer 02547 is made of polymer resins such as EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), PVB (polyvinyl butyral), or two or more composite forms of these resins. These resin materials, due to their low fluidity, can ensure the formation of a uniform and flat surface during the processing process. In order to further improve the performance of the surface insulating layer 02547, polymer particles with a low melt index can be selected, which helps to maintain the stability and consistency of the film during the film forming process.

[0070] The manufacturing process of a bifacial photovoltaic module with a surface-insulating double-sided reflective gap film provided in accordance with this embodiment may include: forming a UV-curable adhesive molding structure with a reflective structure on the front surface of a supporting layer resin by mold transfer, screen printing, or the like; forming an aluminum layer on the surface of the molded front reflective structure by vacuum aluminum plating, sputtering, or the like; forming an aluminum layer on the surface of the molded back reflective structure by vacuum aluminum plating, sputtering, or the like; combining the adhesive layer and the back reflective coating into a whole by using cast lamination, film lamination, or glue coating; combining the surface insulating layer and the surface of the reflective layer into a whole by using cast lamination, film lamination, or glue coating, and subjecting the surface insulating layer to electron irradiation or thermal cross-linking treatment to reduce its fluidity; applying the adhesive layer of the double-sided reflective gap reflective film to a back panel by heating; during packaging, a thinner photovoltaic module backside packaging film may be used, and solar cells may be welded, stacked, and laminated according to the photovoltaic module structure to produce a bifacial photovoltaic module.

[0071] Figure 13 is a schematic diagram of a surface-insulated, double-sided reflective gap film according to an embodiment of the present disclosure. As shown in Figure 13, the surface-insulated, double-sided reflective gap film 0352 includes a backside adhesive layer 03521, an intermediate support layer 03522, a front side reflective structure 03523, and a back side reflective structure 03525. The intermediate support layer 03522 is made of, for example, PET and has a thickness of 10 to 100 μm. The front side reflective structure 03523 is disposed on one side of the intermediate support layer 03522 (the upper side in Figure 13) and includes several ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded using UV-curable adhesive and has an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The back side reflective structure 03525 is disposed on the other side of the intermediate support layer 03522 (the lower side in Figure 13) and includes several ∨-shaped tooth-shaped members arranged side by side. Each ∨-shaped toothed member can be molded with UV curing adhesive at an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The thickness of the back adhesive layer 03521 is no less than the height of the back reflective structure 03525, so that the back reflective structure 03525 is located or completely located within the back adhesive layer 03521. A front reflective layer 03524 is coated on the front reflective structure 03523. The front reflective layer 03524 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. Similarly, the back reflective structure 03525 includes a back reflective layer 03526 coated thereon. The back reflective layer 03526 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. The back adhesive layer 03521 can be made of a polymer resin or composite resin such as EVA or POE, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, the back adhesive layer 03521 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. The back adhesive layer is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0072] A surface insulating layer 03527 is also provided on the front reflective layer 03524 of the front reflective structure 03523, so that the surface insulating layer 03527 covers the surface of the front reflective layer 03524. The surface insulating layer 02527 has an uneven surface. The relatively uneven surface insulating layer can have a larger contact surface area with the adhesive film on the back of the photovoltaic module, thereby further improving the bonding effect and reliability of the gap film and the packaging film. The surface insulating layer 02527 is made of polymer resins such as EVA (ethylene-vinyl acetate copolymer), POE (polyolefin elastomer), PVB (polyvinyl butyral), or two or more composite forms of these resins. In order to further improve the performance of the surface insulating layer 03527, polymer particles with a lower melt index can be selected, which helps to maintain the stability and consistency of the film during the film forming process.

[0073] The manufacturing process of a double-sided photovoltaic module with a surface-insulating double-sided reflective gap film provided in accordance with this embodiment may include: forming a UV-curable adhesive molding structure with a reflective structure on the surface of a support layer resin by mold transfer, screen printing, or the like; forming an aluminum layer on the surface of the molded reflective structure by vacuum aluminum plating, sputtering, or the like; combining an adhesive layer with the above-mentioned structure into a whole by using cast lamination, film lamination, or glue coating; combining a surface insulating layer with the surface of a reflective layer into a whole by using cast lamination, film lamination, or glue coating, and subjecting the surface insulating layer to electron irradiation or thermal cross-linking treatment to reduce its fluidity; applying the adhesive layer of the double-sided reflective gap reflective film to a back panel by heating; and then, during packaging, a thinner photovoltaic module backside packaging film may be used, and solar cells may be welded, stacked, and laminated according to the photovoltaic module structure to produce a double-sided photovoltaic module.

[0074] According to the surface-insulated double-sided reflective gap film of the embodiment of the present disclosure, the adhesive layer of the surface-insulated double-sided reflective gap film is precisely adhered to the back panel of the photovoltaic module by heating. This gap film is not only placed between the battery cells and between the battery strings, but can also be extended to the edges of the photovoltaic module. In this process, the welding of solar cells, the stacking of components and the final lamination process will be carried out in accordance with the standard structural requirements of the photovoltaic module, ensuring that the component enhances reliability while achieving double-sided power generation. Therefore, the photovoltaic module according to the embodiment of the present disclosure can make full use of sunlight, maintain long-term stable operation, and provide strong support for the efficient conversion and application of solar energy.

[0075] As described above, the double-sided reflective gap films of the embodiments shown in Figures 4, 6, and 8 all have a backside reflective structure. Compared to the double-sided reflective gap films of the embodiments shown in Figures 4, 6, and 8, the double-sided reflective gap films of the embodiments shown in Figures 9-13 also have an insulating surface. Table 2 below provides a detailed comparison of the reflective gap films of the embodiments shown in Figures 2, 4, 10, and 13.

[0076] Table 2:

[0077] As mentioned above, a double-sided reflective gap film primarily consists of a backside adhesive layer, an intermediate support layer, a front-side reflective structure, and a back-side reflective structure. To further enhance the reflective effect, a front-side reflective layer is applied to the front-side reflective structure to increase reflectivity. In these structures, the backside adhesive layer and the intermediate support layer are often made of polymer resin materials such as PET. However, these materials are prone to discoloration and structural changes in high-temperature, high-humidity, and UV-irradiated environments, resulting in reduced reliability.

[0078] In response to this problem, an effective solution is to add a certain amount of anti-aging additives and ultraviolet absorbers to the back adhesive layer, or to add a metal coating that can block ultraviolet rays between the intermediate support layer and the back adhesive layer. Anti-aging additives and ultraviolet absorbers or metal coatings can protect the PET material from damage by ultraviolet rays, thereby ensuring the anti-aging ability of the material, while preventing the performance degradation of the double-sided reflective gap film due to the attenuation of the back adhesive layer and the intermediate support layer. However, if the metal coating is too flat, it may reflect the light on the back directly out of the component, which will cause the power on the back of the component to be reduced, thereby affecting the double-sided power generation efficiency of the photovoltaic module. Therefore, it is necessary to design the metal coating to ensure that the metal coating can effectively block ultraviolet rays while minimizing the impact on the back power. In the present disclosure, by precisely controlling the roughness and reflective properties of the metal coating, it is possible to maximize the use of sunlight while protecting the material, thereby improving the overall performance and power generation efficiency of the photovoltaic module.

[0079] Figure 15 is a schematic diagram of a double-sided reflective gap film according to an embodiment of the present disclosure. Figure 16 is a schematic diagram of a double-sided reflective gap film with a metal coating according to an embodiment of the present disclosure. As shown in Figure 15, the double-sided reflective gap film 0451 comprises: a backside adhesive layer 04511, an intermediate support layer 04512, a front side reflective structure 04513, and a back side reflective structure 04515. The intermediate support layer 04512 is made of a transparent or translucent polymer material such as PET, and has a thickness of 10 to 100 μm, preferably 10 to 60 μm. The front side reflective structure 04513 is disposed on one side surface (the top surface in Figure 15) of the intermediate support layer 04512 and comprises a plurality of ∧-shaped tooth-shaped members arranged side by side. Each ∧-shaped tooth-shaped member can be molded using UV-curable adhesive, with an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The overall thickness of the front side reflective structure 04513 is 5 to 20 μm. As shown in FIG16 , parallel texture structures are formed on the surface of the front reflective structure 04513. The angle between the texture structure and the extension direction A of the film strip of the double-sided reflective gap film (see the film strip of the reflective gap film 025 or 035 shown in FIG14 ) is 0 to 90°, preferably 10 to 80°, and more preferably 30 to 60°. The back reflective structure 04515 is disposed on the other side surface of the intermediate support layer 04512 (the lower surface in FIG15 ) and includes a plurality of ∨-shaped tooth-shaped members arranged side by side. Each ∨-shaped tooth-shaped member can be molded using UV-curable adhesive and has an angle of 90 to 150°, preferably 100 to 140°, and more preferably 120°. The overall thickness of the back reflective structure 04515 is 1 to 50 μm, preferably 5 to 20 μm. As shown in FIG16 , the surface of the back reflective structure 04515 is formed with parallel textures. The angle between the texture and the extension direction A of the film strip of the double-sided reflective gap film (see the film strip of the reflective gap film 025 or 035 shown in FIG14 ) is 0-90°. Preferably, the angle between the texture and the extension direction A of the film strip of the double-sided reflective gap film (see the film strip of the reflective gap film 025 or 035 shown in FIG14 ) is 0°, that is, the texture of the back reflective structure 04515 is parallel to the extension direction A of the film strip of the double-sided reflective gap film. Considering the low utilization of sunlight on the back side, a 0° angle results in lower material processing costs. The thickness of the back adhesive layer 04511 is no less than the height of the back reflective structure 04515, ensuring that the back reflective structure 04515 is located within or completely within the back adhesive layer 04511.

[0080] A front reflective layer 04518 is coated on the front reflective structure 04513. The front reflective layer 04518 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm. Similarly, the back reflective structure 04515 includes a back reflective layer 04518 coated thereon. The back reflective layer 04518 can be an aluminum layer formed by vacuum aluminum plating, sputtering, etc., with a thickness of 1 to 100 nm, preferably 20 to 100 nm, and more preferably 30 to 80 nm.

[0081] Back adhesive layer 04511 is made of EVA, POE, PVB polymer resin, or composite resin, with a thickness of 10 to 100 μm, preferably 30 to 90 μm. Preferably, back adhesive layer 04511 is made of cross-linked EVA or POE, with a cross-linking degree of 10-90%, preferably 10-30% or 50-80%, and more preferably 50-65%. The cross-linking degree can be adjusted as needed. For example, the cross-linking degree can depend on the specific formulation, lamination parameters, and testing methods. Back adhesive layer 04511 is used to bond to the transparent backsheet or glass backsheet 014 of the bifacial photovoltaic module.

[0082] In the process of manufacturing the front reflective structure and the back reflective structure, the embossed roller technology is usually used to cure the UV glue to form the required specific structure. However, when the embossed pattern angle is large (more than 10°) with the extension direction of the film strip, if a harder roller is used, it may be difficult to separate from the cured UV glue, resulting in a decrease in the quality of the UV glue structure, thereby affecting the expected reflective effect. In this case, it is generally recommended to use a softer roller, such as a copper roller, to ensure smooth demolding. Relatively speaking, when the angle between the pattern and the extension direction of the film strip is small or basically parallel, even if a harder roller, such as a nickel roller, is used, demolding can be achieved smoothly. Hard rollers wear less during the continuous curing of UV glue and have a longer service life, which helps to significantly reduce production costs.

[0083] Considering the limited amount of sunlight the backside can receive, the gain difference between 0° and angles between 10 and 80° is relatively small and negligible. Therefore, the preferred backside texturing angle of 0° not only reduces damage to the roller during the embossing process but also effectively extends the roller's lifespan, further reducing manufacturing costs. This optimized solution not only ensures reflective effects while also balancing production efficiency and cost control, providing a cost-effective solution for photovoltaic module manufacturing.

[0084] According to this embodiment, the front and back sides of the intermediate support layer of the double-sided reflective gap film are covered with metal coatings. These metal coatings can effectively block ultraviolet rays and prevent the film material from aging and performance failure due to long-term exposure to ultraviolet rays. This feature significantly improves the durability and service life of the gap film. By adding a back-side texture to the back-reflective structure of the gap film, the sunlight in the back-side cell gap area can be more efficiently utilized. This design helps to capture more scattered light and reflected light, thereby improving the bifacial power generation efficiency of the photovoltaic module and increasing the overall energy output.

[0085] It is understood that the embodiments of the present disclosure provide a variety of double-sided reflective gap films, and photovoltaic modules can select one or more of these films based on their specific design and performance requirements. Whether used alone or in combination, these double-sided reflective gap films can provide the various advantages of the embodiments of the present disclosure, providing great flexibility in the manufacture and application of photovoltaic modules, allowing photovoltaic modules to better adapt to different installation environments and energy requirements.

[0086] Example embodiments have been disclosed herein, and although specific terms are employed, they are used and should be interpreted only in a general illustrative sense and not for purposes of limitation. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly indicated, features, characteristics, and / or elements described in conjunction with a particular embodiment may be used alone or in combination with features, characteristics, and / or elements described in conjunction with other embodiments. Therefore, it will be understood by those skilled in the art that various changes in form and detail may be made without departing from the scope of the present disclosure as set forth in the appended claims.

Claims

1. A double-sided reflective gap film, wherein the double-sided reflective gap film is aligned with the gap between two adjacent double-sided photovoltaic cell units of a double-sided photovoltaic module, wherein: The double-sided reflective gap film comprises: a back adhesive layer, an intermediate support layer, a front reflective structure and a back reflective structure. The front reflective structure is arranged on one side of the intermediate support layer and includes a plurality of ∧-shaped toothed components arranged side by side. A front reflective layer is coated on the front reflective structure. The back reflective structure is arranged on the other side of the middle support layer, The thickness of the back adhesive layer is not less than the height of the back reflective structure, so that the back reflective structure is located in the back adhesive layer.

2. The double-sided reflection gap film according to claim 1, wherein: Each of the ∧-shaped toothed components is formed by UV curing adhesive with an angle of 90° to 150°. The front reflective layer is an aluminum layer with a thickness of 20 to 100 nm. The intermediate support layer is made of PET and has a thickness of 10 to 100 μm. The back adhesive layer is made of EVA, POE, PVB polymer resin or composite resin, and has a thickness of 10 to 100 μm.

3. The double-sided reflection gap film according to claim 1 or 2, wherein: The back reflective structure includes a plurality of ∨-shaped toothed components arranged side by side, each of which is formed by UV curing adhesive with an angle of 90° to 150°. The back reflective structure includes a back reflective layer coated on the back reflective structure. The back reflective layer is an aluminum layer with a thickness of 20 to 100 nm.

4. The double-sided reflection gap film according to claim 1 or 2, wherein: The back reflective structure includes spherical particles arranged in a compact manner, and the spherical particles form a reflective coating.

5. The double-sided reflection gap film according to claim 1, wherein: The back reflective structure is located in the back adhesive layer to form a transparent sublayer-reflective sublayer-transparent sublayer structure, wherein the reflective sublayer serves as the back reflective structure.

6. The double-sided reflective gap film according to any one of claims 1 to 5, wherein: A surface insulating layer is further provided on the front reflective layer of the front reflective structure, and the surface insulating layer covers the surface of the front reflective layer. The surface insulating layer has a flat surface. The surface insulation layer is a thermosetting resin and is made of one or more polymer resins selected from EVA, POE, and PVB.

7. The double-sided reflective gap film according to any one of claims 1 to 5, wherein: A surface insulating layer is further provided on the front reflective layer of the front reflective structure, and the surface insulating layer covers the surface of the front reflective layer. The surface insulating layer has an uneven surface, The surface insulation layer is a thermosetting resin and is made of one or more polymer resins selected from EVA, POE, and PVB.

8. The double-sided reflection gap film according to claim 2, wherein: The back reflective structure is a material formed by mixing at least one of titanium dioxide, zirconium oxide, barium sulfate, and aluminum hydroxide into the EVA, POE polymer resin, or composite resin.

9. The double-sided reflection gap film according to claim 1 or 2, wherein: The back reflective structure is an aluminum layer formed on the other side surface of the intermediate support layer by vacuum aluminum plating and sputtering, with a thickness of 20 to 100 nm.

10. The double-sided reflection gap film according to claim 1, wherein: Each of the ∧-shaped toothed components is formed by UV curing adhesive with an angle of 90 to 150 degrees. The overall thickness of the front reflective structure is 1 to 50 μm, and parallel texture structures are formed on the surface of the front reflective structure. The angle between the texture structures and the extension direction of the film strip of the double-sided reflective gap film is 0 to 90°. The front reflective layer is an aluminum layer with a thickness of 20 to 100 nm. The intermediate support layer is made of PET and has a thickness of 10 to 100 μm. The back adhesive layer is made of EVA, POE, PVB polymer resin or composite resin, and has a thickness of 10 to 100 μm.

11. The double-sided reflection gap film according to claim 2 or 10, wherein: The back adhesive layer is made of cross-linked EVA or POE polymer resin or composite resin, and the cross-linking degree is 10-90%.

12. The double-sided reflection gap film according to claim 10, wherein: The back reflective structure includes a plurality of ∨-shaped toothed components arranged side by side, each of which is formed by UV curing adhesive with an angle of 90° to 150°. Parallel texture structures are formed on the surface of the back reflective structure, and an angle between the texture structure and an extending direction of the film strip of the double-sided reflective gap film is 0° to 90°.

13. A bifacial photovoltaic module, comprising: A photovoltaic glass front plate, a front transparent encapsulation film, a back transparent encapsulation film, a transparent back plate or a glass back plate, a double-sided reflective gap film and a plurality of double-sided photovoltaic cell units, wherein the double-sided reflective gap film is the double-sided reflective gap film according to any one of claims 1-12.

14. The bifacial photovoltaic module according to claim 13, wherein: The photovoltaic glass front plate is closely arranged on the front transparent packaging film to protect the front transparent packaging film, and the transparent back plate or glass back plate is closely arranged under the back transparent packaging film to protect the back transparent packaging film. The plurality of bifacial photovoltaic cell units are located side by side between the front transparent packaging film and the back transparent packaging film. The double-sided reflective gap film is located on the lower side of the rear transparent packaging film and is arranged on the transparent back plate or the glass back plate.

Images