Solar spectral splitting film and photovoltaic modules
By using a layered solar beam splitter film and employing total internal reflection technology with triangular prism units, light from gaps and edges is reflected onto the battery surface, solving the problem of low light energy utilization efficiency in existing technologies and achieving efficient light energy recovery.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- NINGBO EXCITON NEW ENERGY CO LTD
- Filing Date
- 2025-04-18
- Publication Date
- 2026-05-26
AI Technical Summary
The light energy utilization efficiency of existing solar panels is low in the gap areas, especially in high-voltage conductive areas and areas where wiring obstructs light energy, resulting in wasted light energy.
The solar beam splitter uses a layered structure, including an upper substrate layer, a prism structure layer, and a lower substrate layer. The prism unit is triangular with a refractive index of 1.45 to 1.8. It reflects gap and edge light to the cell surface through total internal reflection, avoiding conductivity limitations and wiring obstruction.
It significantly improves the efficiency of light energy utilization, avoids light energy waste caused by conductivity limitations and photovoltaic wiring blockage, and improves the overall light energy recovery efficiency of photovoltaic modules.
Smart Images
Figure CN224290520U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of solar cell technology, and in particular to a solar spectral splitting film and a photovoltaic module. Background Technology
[0002] In existing technologies, the gaps between solar panels typically utilize microstructured reflective films with a metallic reflective coating. Their function is to guide incident sunlight into the gaps and recover it onto the panel surface through total internal reflection, thereby improving light conversion efficiency. However, this technology has significant limitations: firstly, the metallic reflective coating, due to its conductivity, cannot be applied to the high-voltage conductive areas of the photovoltaic module, resulting in ineffective light recovery in these critical areas; secondly, when the reflective film is attached below the solar panel, light from the wiring areas of the photovoltaic module cannot be reflected and utilized due to line obstruction, resulting in light loss. These problems severely restrict the overall utilization efficiency of incident light energy by the photovoltaic module.
[0003] In view of the above, this utility model is hereby proposed. Utility Model Content
[0004] One of the objectives of this invention is to provide a solar energy splitting film to alleviate the problems of limited application area and wasted light energy due to wire blockage in the existing technology.
[0005] The second objective of this utility model is to provide a photovoltaic module.
[0006] In order to achieve the above-mentioned objectives of this utility model, the following technical solution is adopted:
[0007] The first aspect of this utility model provides a solar spectral splitting film, comprising an upper substrate layer, a prism structure layer and a lower substrate layer stacked from top to bottom; the prism structure layer includes periodically arranged prism units, the cross-section of the prism unit is triangular, adjacent prism units form a cavity structure, and the refractive index of the prism unit is 1.45 to 1.8.
[0008] In an optional embodiment, the base of the triangle intersects with the upper substrate layer, and the apex borders the lower substrate layer; the other two angles of the triangle are the first base angle and the second base angle.
[0009] In an optional embodiment, a first end and a second end are provided from left to right along the horizontal direction of the upper substrate layer in accordance with the laying direction, with the opening of the first bottom corner facing the first end and the opening of the second bottom corner facing the second end.
[0010] In an optional embodiment, the angle of the apex angle is 40° to 87°, the angle of the first base angle is 43° to 47°, and the margin is the angle of the third base angle.
[0011] In an optional embodiment, the angle of the apex angle is 43° to 80°, the angle of the first base angle is 44° to 47°, and the margin is the angle of the third base angle.
[0012] In an optional embodiment, the angle of the apex angle is 45° to 80°, the angle of the first base angle is 44° to 47°, and the margin is the angle of the third base angle.
[0013] In an optional embodiment, the refractive index of the prism unit is 1.53 to 1.715.
[0014] In an optional embodiment, the thickness of the upper substrate layer is 10–50 μm; the thickness of the prism structure layer is 10–80 μm; and the thickness of the lower substrate layer is 10–50 μm.
[0015] The second aspect of this utility model provides a photovoltaic module, including a plurality of photovoltaic cells, wherein the photovoltaic cells are arranged in a parallel and spaced manner, and gap regions are formed between adjacent cells;
[0016] The solar spectral splitting film is disposed within the gap region.
[0017] Compared with the prior art, the present invention has at least the following beneficial effects:
[0018] The solar energy splitting film provided by this invention significantly improves light energy utilization efficiency and adaptability through a layered structural design and optimized configuration of prism units. The upper and lower substrate layers provide stable support and protection for the prism structure layer. The periodically arranged prism units in the prism structure layer, with their triangular cross-section design and the cavity structure between adjacent prism units, form multiple total internal reflection interfaces, effectively guiding incident light to propagate directionally within the module and reducing scattering losses. The refractive index range of the prism units (1.45–1.8) is strictly matched to ensure that light meets the total internal reflection condition at the prism interface, thereby efficiently reflecting light that would otherwise illuminate the gaps between the solar panels or the blank areas around the module to the photovoltaic cell surface. Furthermore, the cavity structure further optimizes the light path control capability through the difference in refractive index between the air medium and the prism material. Compared to traditional metal-coated reflective films, this solution completely avoids conductivity limitations, making it safe for use in high-voltage conductive areas. It also avoids light energy waste caused by photovoltaic wiring obstruction, thus improving the overall light energy recovery efficiency of the photovoltaic module. Furthermore, the manufacturing process is simple, has minimal cost impact, and is compatible with existing solar module production lines.
[0019] The photovoltaic module provided by this invention, given the advantages of the aforementioned solar energy splitting film, improves the power generation of the photovoltaic module and reduces wiring restrictions. It is suitable for large-scale deployment and use. Attached Figure Description
[0020] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0021] Figure 1 A schematic diagram of the structure of a solar energy splitting film provided by this utility model;
[0022] Figure 2 A schematic diagram of another solar energy splitting film provided by this utility model;
[0023] Figure 3 The present invention provides a light propagation path and layered structure for a photovoltaic module;
[0024] Figure 4 Another photovoltaic module light propagation path and layered structure provided by this utility model.
[0025] Icons: 100 - Upper substrate layer; 110 - First end; 120 - Second end; 200 - Prism structure layer; 300 - Lower substrate layer; 400 - Cavity structure; a - Top corner; b - First bottom corner; c - Second bottom corner. Detailed Implementation
[0026] The embodiments and examples of this utility model will be described in detail below. However, those skilled in the art will understand that the following embodiments and examples are only for illustrating this utility model and should not be considered as limiting the scope of this utility model. All other embodiments obtained by those skilled in the art based on the embodiments of this utility model without creative effort are within the protection scope of this utility model.
[0027] The first aspect of this utility model provides a solar energy splitting film, such as... Figure 1 As shown, it includes an upper substrate layer 100, a prism structure layer 200, and a lower substrate layer 300 stacked from top to bottom; the prism structure layer 200 includes periodically arranged prism units, the cross-section of the prism unit is triangular, and adjacent prism units form a cavity structure 400, the refractive index of the prism unit is 1.45 to 1.8.
[0028] The solar energy splitting film provided by this invention significantly improves light energy utilization efficiency and adaptability through a layered structural design and optimized configuration of prism units. The upper substrate layer 100 and lower substrate layer 300 provide stable support and protection for the prism structure layer 200. The periodically arranged prism units in the prism structure layer 200, with their triangular cross-section design and the cavity structure 400 between adjacent prism units, form multiple total internal reflection interfaces, effectively guiding incident light to propagate directionally within the module and reducing scattering losses. The refractive index range (1.45–1.8) of the prism units is strictly matched to ensure that light meets the total internal reflection condition at the prism interface, thereby efficiently reflecting light that would otherwise illuminate inefficient areas such as gaps or edges of the solar panels to the photovoltaic cell surface. Furthermore, the cavity structure 400 further optimizes the light path control capability through the difference in refractive index between the air medium and the prism material. Compared to traditional metal-coated beam splitters, this solution completely avoids conductivity limitations, making it safe for use in high-voltage conductive areas. It also avoids light energy waste caused by photovoltaic wiring obstruction, thus improving the overall light energy recovery efficiency of the photovoltaic module. Furthermore, the manufacturing process is simple, has minimal cost impact, and is compatible with existing solar module production lines.
[0029] In a specific embodiment of this utility model, the upper substrate layer 100 can be made of materials such as PET, PC, or PMMA. The lower substrate layer 300 can also be made of materials such as PET, PC, or PMMA. It should be noted that the light transmittance of both the upper substrate layer 100 and the lower substrate layer 300 is independently ≥85%.
[0030] The upper substrate layer 100 and the lower substrate layer 300 serve as a protective layer and a support layer, ensuring the physical stability of the prism structure layer 200 while allowing incident light to efficiently penetrate into the prism structure layer 200.
[0031] The cavity structure 400 and the prism structure have a significant difference in refractive index, which enhances the total internal reflection efficiency at the air-prism interface.
[0032] Typical, but not limiting, refractive indices of prism units can be, for example, 1.45, 1.5, 1.6, 1.7, or 1.8, or any value within the range of 1.45 to 1.8. The refractive index of the prism unit is determined by the material forming the prism structure, such as acrylic resin (refractive index 1.49–1.59), polycarbonate (refractive index 1.58–1.65), or modified epoxy resin (refractive index 1.6–1.8). Users can choose the appropriate material based on their actual refractive index requirements.
[0033] In alternative implementations, such as Figure 2 As shown, the base of the triangle intersects with the upper substrate layer 100, and the vertex a is adjacent to the lower substrate layer 300; the other two corners of the triangle are the first base angle b and the second base angle c.
[0034] In an optional embodiment, a first end 110 and a second end 120 are provided from left to right along the horizontal direction of the upper substrate layer 100 in accordance with the laying direction, with the opening of the first bottom corner b facing the first end 110 and the opening of the second bottom corner c facing the second end 120.
[0035] In an optional embodiment, the angle of the apex angle a is 40° to 87°. The angle of the first base angle b is 43° to 47°, with the remainder being the angle of the second base angle c.
[0036] Typically, but not limitingly, the angle of the vertex angle 'a' can be, for example, 40°, 42°, 44°, 47°, 49°, 51°, 53°, 55°, 57°, 59°, 61°, 63°, 65°, 67°, 69°, 71°, 73°, 75°, 77°, 79°, 81°, 83°, 85°, or 87°, or any value within the range of 40° to 87°. The angle of the first base angle 'b' can be, for example, 43°, 44°, 45°, 46°, or 47°, or any value within the range of 43° to 47°. Since the angles of the vertex angle 'a' and the first base angle 'b' are already determined, the angle of the second base angle 'c' can be obtained as (180° - angle of vertex angle 'a' - angle of the first base angle 'b').
[0037] In an optional embodiment, the angle of the apex angle is 43° to 80°, the angle of the first base angle is 44° to 47°, and the margin is the angle of the third base angle.
[0038] In an optional embodiment, the angle of the apex angle is 45° to 80°, the angle of the first base angle is 44° to 47°, and the margin is the angle of the third base angle.
[0039] The geometric design of the prism's apex angle α and base angle, combined with the refractive index gradient, ensures that the light path is controllable and avoids scattering loss.
[0040] In an optional embodiment, the refractive index of the prism unit is 1.53 to 1.715. Typically, but not limitingly, the refractive index of the prism unit can be, for example, 1.53, 1.55, 1.59, 1.61, 1.63, 1.65, 1.67, 1.69, or 1.715, or any value within the range of 1.53 to 1.715.
[0041] In an optional embodiment, the thickness of the upper substrate layer 100 is 10–50 μm; the thickness of the prism structure layer 200 is 10–80 μm; and the thickness of the lower substrate layer 300 is 10–50 μm.
[0042] The second aspect of this utility model provides a photovoltaic module, including a plurality of photovoltaic cells, wherein the photovoltaic cells are arranged in a parallel and spaced manner, and gap regions are formed between adjacent cells;
[0043] The solar spectral splitting film is disposed within the gap region.
[0044] The photovoltaic module provided by this invention, given the advantages of the aforementioned solar energy splitting film, improves the power generation of the photovoltaic module and reduces wiring restrictions. It is suitable for large-scale deployment and use.
[0045] Figure 3 and Figure 4 The light propagation path and layered structure of a photovoltaic module are shown, including:
[0046] The front and back glass are located on the front and back of the photovoltaic module, respectively. They are made of high-transmittance tempered glass with a thickness of 2-3.2mm and their main functions are mechanical support and protection against environmental corrosion.
[0047] Encapsulating film: EVA and EPE encapsulating film covering the upper and lower surfaces of the solar cell, with a thickness of 0.3 to 0.6 mm, used to bond the solar cell to the glass layer, while also providing insulation protection.
[0048] Solar cells: Monocrystalline or polycrystalline silicon photovoltaic cells arranged in parallel intervals, receiving incident and reflected light for photoelectric conversion. Transparent beam-splitting films are attached to the gaps between adjacent cells and around the perimeter of the module to reflect sunlight back into the cells.
[0049] Sunlight, as the incident light, shines vertically or obliquely onto the surface of the photovoltaic module; the light incident on the blank area around the module passes through the beam-splitting prism structure layer and is reflected by total internal reflection onto the front glass surface, and then onto the solar cells.
[0050] Light incident on the gaps between the solar cells undergoes total internal reflection through a transparent beam-splitting film (containing a prism structure layer) to the front glass surface, and then a second reflection back to the solar cell surface. Compared to reflective films, beam-splitting films have a shorter reflection path, reducing light loss and allowing more sunlight to be reflected onto the solar cells.
[0051] This photovoltaic module significantly improves the utilization rate of incident light energy by integrating a beam splitter and an encapsulation layer, especially solving the problem of light energy waste in the gaps between cells and edge areas.
[0052] The present invention will be further illustrated below with specific embodiments and comparative examples. However, it should be understood that these embodiments are merely for the purpose of more detailed illustration and should not be construed as limiting the present invention in any way. Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present invention are produced under conventional conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all conventional products that can be purchased commercially.
[0053] Examples 1-7
[0054] These embodiments provide a solar spectral splitter, with a structure as follows: Figure 2 As shown, the cross-section of the prism unit is triangular.
[0055] The upper substrate layer 100 has a thickness of 38μm, the prism structure layer 200 has a thickness of 50μm, and the lower substrate layer 300 has a thickness of 38μm.
[0056] The upper substrate layer 100 is made of PET with a light transmittance of 92%; the lower substrate layer 300 is also made of PET with a light transmittance of 92%.
[0057] Other parameter changes are shown in Table 1.
[0058] Comparative Example 1
[0059] This comparative example provides an aluminum-coated reflective film, model BC81, manufactured by Heyu.
[0060] Test case
[0061] The power generation of the modules was tested by combining the spectral splitters of the examples and comparative examples, and the data obtained are recorded in Table 1.
[0062] Table 1
[0063]
[0064] As can be seen from Table 1, the combination of different refractive indices of the beam splitting film and the prism structure provided by this utility model can effectively improve the power generation of the photovoltaic module.
[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this utility model, and are not intended to limit it. Although the utility model has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this utility model.
Claims
1. A solar light splitting film, characterized by, It includes an upper substrate layer, a prism structure layer, and a lower substrate layer stacked from top to bottom; The prism structure layer includes periodically arranged prism units, each with a triangular cross-section, and adjacent prism units form a cavity structure. The refractive index of the prism unit is 1.45 to 1.
8.
2. The solar spectrophotometry film according to claim 1, wherein The base of the triangle intersects with the upper substrate layer, and the apex of the triangle is adjacent to the lower substrate layer. The other two angles of the triangle are the first base angle and the second base angle.
3. The solar spectrophotometry film according to claim 2, wherein, A first end and a second end are provided from left to right along the horizontal direction of the upper substrate layer in accordance with the laying direction; The opening at the first bottom corner faces the first end, and the opening at the second bottom corner faces the second end.
4. The solar spectrometry film according to claim 2 or 3, wherein The angle of the apex is 40° to 87°, the angle of the first base angle is 43° to 47°, and the remainder is the angle of the third base angle.
5. The solar energy splitting film according to claim 2 or 3, characterized in that, The angle of the apex is 43° to 80°, the angle of the first base angle is 44° to 47°, and the margin is the angle of the third base angle.
6. The solar spectrometry film according to claim 2 or 3, wherein The angle of the apex is 45° to 80°, the angle of the first base angle is 44° to 47°, and the remainder is the angle of the third base angle.
7. The solar spectrophotometry film of claim 1, wherein, The refractive index of the prism unit is 1.53 to 1.
715.
8. The solar spectrophotometry film of claim 1, wherein, The thickness of the upper substrate layer is 10–50 μm; the thickness of the prism structure layer is 10–80 μm; and the thickness of the lower substrate layer is 10–50 μm.
9. A photovoltaic module, characterized by It includes multiple photovoltaic cells, which are arranged in a parallel and spaced manner, with gap regions formed between adjacent cells; The solar spectral splitting film according to any one of claims 1 to 8 is disposed in the gap region.