Black high-reflective insulating light guide film and photovoltaic module

Abstract

The utility model discloses a kind of black high-reflective insulating light guide film and photovoltaic module, light guide film is designed through six functional laminated, realize the synergic optimization of optical performance and structural reliability in photovoltaic module, the transmission of infrared light and the directional reflection effect of metal reflection layer on the surface of prism structure form coupling through first black coating, infrared light line incident to cell gap is efficiently guided to cell, significantly improve the utilization of photovoltaic module to infrared band in solar spectrum, simultaneously, the dark appearance of first black coating in visible light band perfectly shields cell gap, ensure photovoltaic module appearance uniformity, and its insulating characteristic effectively blocks electric leakage channel, guarantee photovoltaic module electrical safety, provide stable support to suppress laminated deformation by substrate layer, in combination with the stress buffering and interface matching ability of bonding layer, ensure the long-term stability of photovoltaic module under harsh environment, make double-glass photovoltaic module have the advantages of full-black appearance and higher power generation gain.

Description

Technical Field

[0001] This utility model belongs to the field of reflective film technology, and relates to an insulating light guide film, specifically a black high-reflectivity insulating light guide film and a photovoltaic module with the light guide film bonded thereon. Background Technology

[0002] In crystalline silicon photovoltaic modules, the gaps between cells and between cells and the frame cannot effectively utilize incident light, resulting in light energy loss. Especially to meet the aesthetic requirements of building-integrated photovoltaics (BIPV) and other applications where the front of the module needs to appear black, using black materials to fill the gaps between cells or between cells and the frame results in near-zero light utilization in these gap areas due to the strong absorption of visible and infrared light by the black material, leading to further light energy loss. While white reflective strips can improve reflectivity, they create a strong color difference with the black cells, failing to meet the uniformity requirements of the high-end market for photovoltaic modules. Printing black grids or applying black enamel to a transparent substrate can utilize light in the gap areas to some extent while maintaining a uniform black appearance, but this requires additional masking and sintering processes, significantly increasing production costs, and the light utilization rate is also low. Therefore, developing a light guide film that combines a black appearance, high infrared reflectivity, and low processing cost has become a pressing technical challenge to improve the power density and market competitiveness of photovoltaic modules. Utility Model Content

[0003] To address the technical problems existing in the background art, this utility model proposes a black high-reflectivity insulating light guide film and a photovoltaic module with the light guide film bonded on it. The light guide film has the characteristics of black appearance, high infrared reflectivity and low manufacturing cost.

[0004] The objective of this utility model can be achieved through the following technical solutions:

[0005] A black high-reflectivity insulating light guide film includes, from top to bottom, the following layers stacked sequentially: a first black coating layer, a metal reflective layer, a light guide layer, a substrate layer, a second black coating layer, and an adhesive layer. The first black coating layer is an insulating black coating that transmits infrared light. The upper surface of the light guide layer has multiple prism structures. The metal reflective layer covers the surface of the multiple prism structures to form a directional reflection interface.

[0006] Furthermore, the metal reflective layer is made of a highly reflective aluminum plating layer, and the metal reflective layer tightly covers the contour of the prism structure.

[0007] Furthermore, the metal reflective layer is uniformly coated on the surface of multiple prism structures by vacuum evaporation or magnetron sputtering.

[0008] Furthermore, multiple prism structures on the light guide layer are arranged in a periodic and continuous manner. The height of the prism structure is 1-40μm, the angle between the length extension line of the prism structure and the length extension line of the light guide film is 0 degrees to 90 degrees, and the apex angle of the prism structure is 70 degrees to 110 degrees.

[0009] Furthermore, the first black coating uses infrared-transmitting resin and infrared-transmitting black pigment. The infrared-transmitting black pigment is uniformly dispersed in the infrared-transmitting resin. The first black coating has an infrared light transmittance of 60%-95% in the 800-1200nm wavelength band and a reflectance of 1%-5% in the visible light band.

[0010] Furthermore, the light guide layer is made of UV-cured optical resin or polycarbonate.

[0011] Furthermore, the substrate layer is made of transparent PET film, PI film or PMMA film, with a thickness of 20-250μm.

[0012] Furthermore, the second black coating uses acrylic resin and carbon black particles, with a thickness of 3-20 μm, and the carbon black particles are uniformly dispersed in the acrylic resin.

[0013] Furthermore, the adhesive layer uses optically transparent adhesive or hot melt adhesive film with a thickness of 10-150μm.

[0014] A photovoltaic module with the light guide film bonded thereto includes: a plurality of solar cells arranged in a matrix, the light guide film being arranged in a cross shape between any four adjacent solar cells, a first transparent adhesive film and a second transparent adhesive film being respectively attached to the upper and lower surfaces of the solar cells, a first protective glass covering the upper surface of the first transparent adhesive film, a second protective glass covering the lower surface of the second transparent adhesive film, and the light guide film being bonded between the second transparent adhesive film and the second protective glass.

[0015] The beneficial effects of this utility model are as follows: The black high-reflectivity insulating light guide film provided in this application achieves synergistic optimization of optical performance and structural reliability in photovoltaic modules through a six-layer functional stacked design. The infrared light transmittance of the first black coating layer is coupled with the directional reflection of the metal reflective layer on the prism structure surface, which efficiently guides the infrared light incident on the gap between the cells to the cells, significantly improving the utilization rate of the infrared band in the solar spectrum of the photovoltaic module. At the same time, the deep black appearance of the first black coating layer in the visible light band perfectly shields the gap between the cells, ensuring the uniformity of the photovoltaic module's appearance. Furthermore, its insulating properties effectively block leakage channels, ensuring the electrical safety of the photovoltaic module. The substrate layer provides stable support to suppress lamination deformation, and combined with the stress buffering and interface matching capabilities of the adhesive layer, it ensures the long-term stability of the photovoltaic module in harsh environments, enabling the double-glass photovoltaic module to have both an all-black appearance and higher power generation gain. Attached Figure Description

[0016] Figure 1 This is a top view of the photovoltaic module of this utility model.

[0017] Figure 2 This is a cross-sectional schematic diagram of the photovoltaic module of this utility model.

[0018] Figure 3 This is a schematic diagram of the structure of the light guide film of this utility model. Detailed Implementation

[0019] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0020] like Figure 1 As shown, this utility model provides a photovoltaic module with a black highly reflective insulating light guide film bonded together, comprising: multiple solar cells 1 arranged in a matrix, and a light guide film 6 arranged in a cross shape between any four adjacent solar cells 1. The cross-shaped arrangement allows the light guide film 6 to precisely cover the gap areas of the solar cells 1, utilizing the directional light guiding of the light guide film 6 to convert the waste infrared light from the gaps in traditional photovoltaic modules into effective power generation. Figure 2 As shown, a first transparent film 2 and a second transparent film 3 are respectively attached to the upper and lower surfaces of the solar cell 1. The upper surface of the first transparent film 2 is covered with a first protective glass 4, and the lower surface of the second transparent film 3 is covered with a second protective glass 5. The light guide film 6 is bonded between the second transparent film 3 and the second protective glass 5, ensuring stable installation and improving the photovoltaic module's resistance to mechanical impact.

[0021] like Figure 3 As shown, the light guide film comprises, from top to bottom, the following layers stacked sequentially: a first black coating layer 10, a metal reflective layer 20, a light guide layer 30, a substrate layer 40, a second black coating layer 50, and an adhesive layer 60. The adhesive layer 60 uses optically transparent adhesive or hot-melt adhesive film with a thickness of 10-150 μm to ensure reliable adhesion between the light guide film 6 and the second protective glass 5, and to suppress the generation of air bubbles after lamination.

[0022] The first black coating 10 is an infrared-transmitting insulating black coating that serves as a light incident interface, achieving the dual functions of infrared light transmission and visible light absorption. It directs more than half of the energy in sunlight—infrared light—to the lower layer, significantly improving the utilization rate of infrared light. Simultaneously, it presents a pure black appearance, eliminating stray light from the gaps between the solar cells 1, enhancing the aesthetics of the photovoltaic module. Furthermore, its insulating properties can mitigate the risk of leakage between the solar cells 1. Specifically, the first black coating 10 uses infrared-transmitting resin and infrared-transmitting black pigment. The infrared-transmitting black pigment is uniformly dispersed in the infrared-transmitting resin, resulting in an infrared light transmittance of 60%-95% in the 800-1200nm wavelength band and a reflectance of 1%-5% in the visible light band. This solves the fundamental contradiction of traditional black materials blocking infrared light.

[0023] The upper surface of the light guide layer 30 has multiple prism structures, and the metal reflective layer 20 covers the surface of the multiple prism structures to form a directional reflection interface, reflecting infrared light that penetrates the first black coating layer 10 to the solar cell 1 at a specific angle, thereby increasing the light utilization rate of the photovoltaic module. Specifically, the multiple prism structures on the light guide layer 30 are arranged in a periodic and continuous manner. The height of the prism structure is 1-40 μm, the angle between the length extension line of the prism structure and the length extension line of the light guide film is 0 degrees to 90 degrees, and the apex angle of the prism structure is 70 degrees to 110 degrees, so that the incident light meets the total internal reflection condition and improves the guiding efficiency of infrared light. The light guide layer 30 uses a UV-cured optical resin layer or a polycarbonate layer, which has a high refractive index and enhances the total internal reflection effect.

[0024] The metal reflective layer 20 employs a high-reflectivity aluminum plating layer with a reflectivity ≥90%. Furthermore, the metal reflective layer 20 tightly covers the contours of the prism structure, ensuring that the angle between the reflected light and the surface of the solar cell 1 is ≤30°, thus reducing light scattering loss. Specifically, the metal reflective layer 20 is uniformly coated onto the surfaces of multiple prism structures via vacuum evaporation or magnetron sputtering, ensuring uniform coverage of the aluminum plating layer on the prism structure surfaces. This avoids light-guiding failure caused by localized decreases in reflectivity, thereby improving product yield. The upper surface of the first black coating layer 10 is planar, and the lower surface of the light-guiding layer 30 is planar. The lower surface of the first black coating layer 10 fills the spaces between the multiple prism structures of the light-guiding layer 30.

[0025] The substrate layer 40 is made of transparent PET film, PI film, or PMMA film with a thickness of 20-250μm, achieving a balance between mechanical strength and lightweight, reducing the weight load of the photovoltaic module while suppressing lamination deformation of the prism structure. The second black coating layer 50, as a general black coating layer, uses acrylic resin and carbon black particles to shield the gap circuit of the solar cell 1 and eliminate visual stray light. The second black coating layer adopts an ultra-thin design with a thickness of 3-20μm to avoid affecting the lamination thickness of the photovoltaic module. By uniformly dispersing the carbon black particles in the acrylic resin, excellent adhesion is provided.

[0026] The above description is merely an example and illustration of the structure of this utility model. Those skilled in the art can make various modifications or additions to the specific embodiments described or use similar methods to replace them, as long as they do not deviate from the structure of the utility model or exceed the scope defined in the claims, they should all fall within the protection scope of this utility model.

Claims

1. A black, highly reflective, insulating light guide film, characterized in that, The material comprises, from top to bottom, the following layers stacked sequentially: a first black coating layer (10), a metal reflective layer (20), a light guide layer (30), a substrate layer (40), a second black coating layer (50), and an adhesive layer (60). The first black coating layer (10) is an insulating black coating that transmits infrared light. The upper surface of the light guide layer (30) has multiple prism structures. The metal reflective layer (20) covers the surface of the multiple prism structures to form a directional reflection interface.

2. The light guide film according to claim 1, characterized in that, The metal reflective layer (20) is made of a highly reflective aluminum-plated layer, and the metal reflective layer (20) tightly covers the contour of the prism structure.

3. The light guide film according to claim 2, characterized in that, The metal reflective layer (20) is uniformly covered on the surface of multiple prism structures by vacuum evaporation or magnetron sputtering.

4. The light guide film according to claim 1, characterized in that, Multiple prism structures on the light guide layer (30) are arranged in a periodic continuous manner. The height of the prism structure is 1-40μm. The angle between the extension line of the prism structure in the length direction and the extension line of the light guide film in the length direction is 0 degrees to 90 degrees. The apex angle of the prism structure is 70 degrees to 110 degrees.

5. The light guide film according to claim 1, characterized in that, The first black coating (10) uses infrared-transmitting resin and infrared-transmitting black pigment. The infrared-transmitting black pigment is uniformly dispersed in the infrared-transmitting resin. The first black coating (10) has an infrared light transmittance of 60%-95% in the 800-1200nm band and a reflectance of 1%-5% in the visible light band.

6. The light guide film according to claim 1, characterized in that, The light guide layer (30) is made of UV-cured optical resin or polycarbonate.

7. The light guide film according to claim 1, characterized in that, The substrate layer (40) is made of transparent PET film, PI film and PMMA film, with a thickness of 20-250μm.

8. The light guide film according to claim 1, characterized in that, The second black coating (50) is made of acrylic resin and carbon black particles, with a thickness of 3-20 μm. The carbon black particles are uniformly dispersed in the acrylic resin.

9. The light guide film according to claim 1, characterized in that, The adhesive layer (60) is made of optically transparent adhesive or hot melt adhesive film with a thickness of 10-150μm.

10. A photovoltaic module with a light guide film as described in any one of claims 1-9 bonded together, characterized in that, include: Multiple battery cells (1) are arranged in a matrix. A light guide film (6) is arranged in a cross shape between any four adjacent battery cells (1). A first transparent film (2) and a second transparent film (3) are respectively attached to the upper and lower surfaces of the battery cells (1). A first protective glass (4) is covered on the upper surface of the first transparent film (2), and a second protective glass (5) is covered on the lower surface of the second transparent film (3). The light guide film (6) is bonded between the second transparent film (3) and the second protective glass (5).

Images