Black photovoltaic module
By attaching a white backing film to the back of the solar cell to reflect long-wavelength light, combined with a low-cost black backsheet and encapsulant film, the problems of energy loss and high cost of traditional black photovoltaic modules are solved, achieving efficient light utilization and aesthetic appeal.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- GCL SYST INTEGRATION TECH CO LTD
- Filing Date
- 2025-06-30
- Publication Date
- 2026-06-23
AI Technical Summary
Traditional black photovoltaic modules suffer from energy loss when using long-wavelength light, and the high-reflectivity black material is expensive.
A white backing film is attached to the back of the solar cell. The white backing film reflects the long-wavelength light that passes through the solar cell back into the cell for use. Combined with a low-cost black backsheet and adhesive film, a black appearance is achieved.
It improves light utilization, reduces optical loss, reduces absorption of long-wavelength light, and lowers component costs.
Smart Images
Figure CN224402020U_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of photovoltaic technology, and specifically to black photovoltaic modules. Background Technology
[0002] A photovoltaic (PV) module consists of cells, glass, a backsheet, encapsulant film, a frame, and a junction box. Traditional PV modules typically feature blue monocrystalline silicon cells paired with a white backsheet or a transparent double-glass design and a metallic frame. In some scenarios, the appearance of PV modules becomes a primary concern. For example, users often prefer black PV modules for their aesthetically pleasing design when installed on rooftops.
[0003] The white reflective enamel coating on the white backsheet or rear glass surface is exposed to the front of the photovoltaic module through the gaps between the cells and between the cells and the frame. To make the gaps between the cells and between the cells and the frame appear black, black adhesive film or black backsheets are used to create black photovoltaic modules.
[0004] The black adhesive film has a three-layer structure consisting of black, white, and black layers, or a two-layer structure consisting of black and white layers. The top black adhesive film makes the gaps between the solar cells and between the solar cells and the frame appear black, while the bottom white adhesive film reflects long-wavelength light that passes through the solar cells and the top black adhesive film back to the solar cells. However, long-wavelength light that is not absorbed by the solar cells has some energy absorbed when it passes through the top black adhesive film. After being reflected by the white adhesive film, it re-enters the black surface and absorbs some energy again, resulting in a significant loss of long-wavelength energy.
[0005] Single-glass black modules utilize a black backsheet. The black backsheet has a layer of highly reflective black material covering its front side. Long wavelengths passing through the solar cells are reflected back to the cells by this highly reflective black material. Highly reflective materials are expensive, increasing the cost of photovoltaic modules. Utility Model Content
[0006] This disclosure provides a black photovoltaic module that improves the utilization of long-wavelength light by eliminating the need for highly reflective black materials.
[0007] According to some embodiments of this disclosure, a black photovoltaic module includes a plurality of solar cells, a white backing film is attached to the back of the solar cells, the area of the white backing film is smaller than the area of the solar cells, and the edge of the white backing film is recessed relative to the outline of the solar cells.
[0008] In some embodiments, the black photovoltaic module also includes a front cover, a front encapsulant film, a rear encapsulant film, and a rear cover, wherein the front encapsulant film and the rear encapsulant film seal the solar cell between the front cover and the rear cover, the front encapsulant film being located on the front side of the solar cell and the rear encapsulant film being located on the rear side of the white backing film.
[0009] In some embodiments, the post-adhesive film includes a black adhesive film.
[0010] In some embodiments, the back cover includes a polymer backsheet, and the side of the back cover facing the front surface of the black photovoltaic module is covered with a layer of black material.
[0011] In some embodiments, a black grid layer is provided on the front side of the rear cover, and the solar cells are arranged in a rectangular array. The black grid layer corresponds to the gaps between the solar cells and the gaps between the solar cells and the edges of the rear cover.
[0012] In some embodiments, the solar cell includes a positive electrode and a negative electrode, which are respectively disposed on both sides of the solar cell, or both the positive electrode and the negative electrode are disposed on the back of the solar cell.
[0013] In some embodiments, the white base film is one or more of the following: EVA film, EPE film, POE film, PVB film, and PO film.
[0014] In some embodiments, the thickness of the white base film is 20 μm to 200 μm.
[0015] In some implementations, the area of the white backing film is greater than or equal to 70% and less than 100% of the area of the solar cell.
[0016] In some embodiments, the white backing film has an average reflectivity of greater than 80% in the 300–1200 nm light band when in air.
[0017] According to another aspect of this disclosure, a black photovoltaic module is provided, comprising a battery string formed by multiple solar cells arranged in a series, with the edges of adjacent solar cells overlapping, and a white backing film that covers all solar cells in the battery string is attached to the back of each battery string, the area of the white backing film being smaller than the area of the battery string, and the edge of the white backing film being recessed relative to the outline of the battery string.
[0018] In some implementations, the area of the white base film is greater than or equal to 70% and less than 100% of the area of the battery string.
[0019] This invention involves attaching a white backing film to the back of a solar cell. This white backing film reflects long-wavelength light passing through the solar cell back to it for utilization. Compared to existing technologies that use only black adhesive film to fabricate black photovoltaic modules, this invention's white backing film reduces the absorption of long-wavelength light by the black adhesive film. Compared to expensive, highly reflective black backsheets, this invention's white backing film can be used with relatively inexpensive conventional black backsheets, maintaining good optical utilization while achieving a black effect. Attached Figure Description
[0020] To more clearly illustrate the specific embodiments of the present invention 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 the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0021] Figure 1 A black photovoltaic module according to some embodiments of the present invention is shown.
[0022] Figure 2 It shows Figure 1 An exploded view of the black photovoltaic module shown.
[0023] Figure 3 A black photovoltaic module according to other embodiments of the present invention is shown.
[0024] Figure 4 It shows Figure 3 An exploded view of the black photovoltaic module shown.
[0025] Figure 5 A black photovoltaic module with other embodiments of the present invention is shown.
[0026] Figure 6 It shows Figure 5 Front view of the rear cover plate in the illustrated embodiment.
[0027] Figure 7 A rear view of the cell string of a black photovoltaic module is shown in some other embodiments of this disclosure. Detailed Implementation
[0028] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort should fall within the scope of protection of the present application.
[0029] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.
[0030] Figure 1 , Figure 3 and Figure 5 Black photovoltaic modules from different embodiments of this disclosure are shown respectively. Figure 2 and Figure 4They were displayed respectively Figure 1 and Figure 3 Exploded view. Please refer to some embodiments of this disclosure. Figure 1 , Figure 3 or Figure 5 The black photovoltaic module includes multiple solar cells 1. A white backing film 2 is attached to the back of the solar cells 1. The area of the white backing film 2 is smaller than that of the solar cells 1, and the edge of the white backing film 2 is recessed relative to the outline of the solar cells 1.
[0031] The area of the white backing film 2 is smaller than that of the solar cell 1, and the edge of the white backing film 2 is recessed relative to the edge of the solar cell 1, so that the white backing film 2 is completely hidden on the back of the solar cell 1. The white backing film 2 is white and has a high reflectivity to light. The white backing film 2 is used to reflect long-wavelength light that has passed through the solar cell 1 back to the solar cell 1 for use.
[0032] Compared to existing technologies that only utilize black adhesive film to prepare black photovoltaic modules, the white base film 2 in this embodiment reduces the absorption of long-wavelength light by the black adhesive film. Compared to high-cost, high-reflectivity black backsheets, the white base film 2 in this embodiment can be paired with relatively inexpensive conventional black backsheets, maintaining good optical efficiency while achieving a black effect.
[0033] In some embodiments, please combine Figures 1 to 5 The black photovoltaic module also includes a front cover plate 3, a front encapsulant film 4, a rear encapsulant film 5, and a rear cover plate 6. The front encapsulant film 4 and the rear encapsulant film 5 seal the solar cell 1 between the front cover plate 3 and the rear cover plate 6. The front encapsulant film 4 is located on the front side of the solar cell 1, and the rear encapsulant film 5 is located on the rear side of the white base film 2.
[0034] Specifically, the front cover plate 3 is constructed of an impact-resistant and optically transparent material, such as transparent tempered glass. The front adhesive film 4 is an optically transparent polymer material, such as transparent ethylene-vinyl acetate copolymer (EVA), transparent polyolefin elastomer (POE), or a co-extruded film of EVA, POE, and EVA (EPE). Light can pass through the front cover plate 3 and the front adhesive film 4 to illuminate the solar cell 1. The front adhesive film 4 and the rear adhesive film 5 seal the solar cell 1, preventing water, gas, and other substances harmful to the solar cell 1 from contacting it. The rear cover plate 6 provides anti-slip properties to the back of the solar cell 1.
[0035] The black photovoltaic module also includes a black frame 7. The frame 7 is configured to surround the photovoltaic module. Specifically, the front cover plate 3, the front encapsulant film 4, the solar cell 1, the rear encapsulant film 5, and the rear cover plate 6 are thermally laminated to form a laminate, and the frame 7 surrounds the laminate. The frame 7 can be made of aluminum alloy, stainless steel, or a polymer composite material.
[0036] Solar cell 1 is interconnected by solder ribbons and busbars. The busbars are configured to be black on at least the front surface facing the black photovoltaic module. In some black photovoltaic modules, the solder ribbons may be black. In some black photovoltaic modules, the solder ribbons may not be black.
[0037] In some embodiments, please refer to Figure 1 and Figure 2 The back film 5 includes a black adhesive film. Exemplarily, the back film 5 can be a single-layer black adhesive film or a multi-layer structure. Exemplarily, the back film 5 can include a black adhesive film on the top layer and a white or transparent adhesive film below it, or the back film 5 can include a transparent adhesive film on the top layer and a black adhesive film below it. The black adhesive film allows the gaps between the solar cells 1 and between the solar cells 1 and the edge of the back cover plate 6 to appear black. The white back film 2 reflects light that is not absorbed by the solar cells 1, such as long-wavelength light, back to the solar cells 1. The black photovoltaic module of this embodiment, by using a white back film 2 in combination with a black adhesive film, improves light utilization and reduces optical loss compared to photovoltaic modules using only a black adhesive film.
[0038] In some embodiments, please refer to Figure 3 and Figure 4 The back cover 6 includes a polymer backsheet, and the side of the back cover 6 facing the front surface of the black photovoltaic module is completely covered with a black material layer. The black material layer makes the back cover 6 appear black when viewed from the front. In this embodiment, the back adhesive film 5 is a transparent adhesive film. The black photovoltaic module of this embodiment improves the selectivity of the black backsheet. More specifically, the black photovoltaic module of this embodiment can choose a lower-cost conventional black backsheet instead of using an expensive high-reflectivity black backsheet. The conventional black backsheet allows the gaps between the solar cells 1 and between the solar cells 1 and the edge of the back cover 6 to appear black, while the white backing film 2 can reflect light that is not absorbed by the solar cells 1, such as long-wavelength light, back to the solar cells 1, preventing the light transmitted through the solar cells 1 from being absorbed by the conventional black backsheet.
[0039] Figure 6 It indicated Figure 5 A front view of the rear cover 6 in the illustrated embodiment. In some embodiments, please refer to... Figure 5 and Figure 6A black mesh layer 8 is provided on the front side of the back cover plate 6. The solar cells 1 are arranged in a rectangular array, and the black mesh layer 8 corresponds to the gaps between the solar cells 1 and the gaps between the solar cells 1 and the edges of the back cover plate 6. In these embodiments, the back cover plate 6 may include transparent glass or an opaque polymer backsheet. The black mesh layer 8 is exposed to the front of the photovoltaic module through the gaps between the solar cells 1 and the gaps between the solar cells 1 and the back cover plate 6, giving these gaps a black effect. The white backing film 2 can reflect the light transmitted through the solar cells 1 back to the solar cells 1 for reabsorption. Compared with conventional double-glass photovoltaic modules, this improves the absorption of light by the photovoltaic module, especially long-wavelength light.
[0040] In some embodiments, the solar cell 1 includes a positive electrode and a negative electrode, which are respectively disposed on both sides of the solar cell 1, or both the positive and negative electrodes are disposed on the back side of the solar cell 1. For example, the positive and negative electrodes of the solar cell 1 are respectively disposed on both sides of the solar cell 1; for example, the solar cell 1 can be a tunnel oxide passivated contact (TOPCon) cell, a heterojunction (HJT) cell, or an emitter passivated and back contact (PERC) cell. For example, the positive and negative electrodes of the solar cell 1 are both disposed on the back side of the solar cell 1, such as an interdigitated back contact (IBC) cell or a metal through-hole wound (MWT) cell.
[0041] In some embodiments, the white base film 2 can be one or more of EVA film, POE film, EPE film, polyvinyl butyral (PVB) film, and polyolefin (PO) film. In some embodiments of this invention, the glass transition temperature of the white base film 2 is below -40°C, and the melting point is below 145°C. The white base film 2 can be attached to the back of the solar cell 1 by hot pressing. Specifically, after the solar cells are interconnected into a battery string using solder ribbons, the white base film 2 is attached to the back of each solar cell, and then infrared heating or thermal contact heating is applied with pressure to bond the white base film 2 to the back of the battery. The battery string is stacked and laminated in the manner of front cover plate 3, front adhesive film 4, battery array, rear adhesive film 5, and rear cover plate 6 to form a laminate.
[0042] In some embodiments, the area of the white backing film 2 is greater than or equal to 70% and less than 100% of the area of the solar cell 1. In this embodiment, most of the solar cell area of the black photovoltaic module is covered by the white backing film 2, which allows for good utilization of light.
[0043] Preferably, the white substrate 2 has an average reflectivity of more than 80% in the 300-1200nm light band in air. The white substrate 2 can better reflect the light transmitted through the solar cell.
[0044] In some embodiments, the thickness of the white backing film 2 is 20 μm to 200 μm. The white backing film 2 has sufficient thickness to prevent excessive light from passing through it. Preferably, the basis weight of the white backing film 2 is 20 g / m³. 2 ~200g / m 2 .
[0045] Figure 7 A rear view of the cell string of a black photovoltaic module is shown in some other embodiments of this disclosure.
[0046] According to another aspect of this disclosure, a black photovoltaic module is provided, such as... Figure 7 As shown, a battery string 9 comprises multiple solar cells 1 arranged in a series, with the edges of adjacent solar cells 1 overlapping. A white backing film 2, covering all solar cells 1 within the string 9, is attached to the back of each battery string 9. The area of the white backing film 2 is smaller than the area of the battery string 9, and the edges of the white backing film 2 are recessed relative to the outline of the battery string 9. After the battery string 9 is fabricated, a longer white backing film 2 can be attached to the back of the battery string 9 to cover all solar cells 1 within it. In this embodiment, the edges of adjacent solar cells 1 within the battery string 9 overlap, therefore there are no gaps between the solar cells 1 within the battery string 9, but gaps exist between battery strings 9 themselves. The black photovoltaic modules in these embodiments can be encapsulated using conventional black adhesive film or conventional black backsheet.
[0047] In some embodiments, the area of the white base film 2 is greater than or equal to 70% and less than 100% of the area of the battery string 9. In this embodiment, most of the battery string of the black photovoltaic module is covered by the white base film 2, which allows for good optical utilization.
[0048] Finally, it should be noted that the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A black photovoltaic module, characterized in that, It includes multiple solar cells, with a white backing film attached to the back of each solar cell. The area of the white backing film is smaller than the area of the solar cell, and the edges of the white backing film are recessed relative to the outline of the solar cell.
2. The black photovoltaic module according to claim 1, characterized in that, The black photovoltaic module also includes a front cover plate, a front encapsulant film, a rear encapsulant film, and a rear cover plate. The front encapsulant film and the rear encapsulant film seal the solar cell between the front cover plate and the rear cover plate. The front encapsulant film is located on the front side of the solar cell, and the rear encapsulant film is located on the rear side of the white base film.
3. The black photovoltaic module according to claim 2, characterized in that, The post-adhesive film includes a black adhesive film.
4. The black photovoltaic module according to claim 2, characterized in that, The back cover includes a polymer backsheet, and the side of the back cover facing the front surface of the black photovoltaic module is completely covered with a black material layer.
5. The black photovoltaic module according to claim 2, characterized in that, The front side of the rear cover plate is provided with a black grid layer, and the solar cells are arranged in a rectangular array. The black grid layer corresponds to the gap between the solar cells and the gap between the solar cells and the edge of the rear cover plate.
6. The black photovoltaic module according to claim 2, characterized in that, The solar cell includes a positive electrode and a negative electrode, which are respectively disposed on both sides of the solar cell, or both the positive electrode and the negative electrode are disposed on the back of the solar cell.
7. The black photovoltaic module according to claim 1, characterized in that, The white base film is one or more of the following: EVA film, EPE film, POE film, PVB film, and PO film.
8. The black photovoltaic module according to claim 1, characterized in that, The thickness of the white base film is 20μm to 200μm.
9. The black photovoltaic module according to claim 1, characterized in that, The area of the white base film is greater than or equal to 70% and less than 100% of the area of the solar cell.
10. The black photovoltaic module according to claim 1, characterized in that, The white base film has an average reflectivity of over 80% in the 300–1200 nm light band when exposed to air.
11. A black photovoltaic module, characterized in that, The battery string comprises multiple solar cells arranged in a series, with the edges of adjacent solar cells overlapping. Each battery string has a white backing film attached to its back that covers all the solar cells within the string. The area of the white backing film is smaller than the area of the battery string, and the edges of the white backing film are recessed relative to the outline of the battery string.
12. The black photovoltaic module according to claim 11, characterized in that, The area of the white base film is greater than or equal to 70% and less than 100% of the area of the battery string.