A bifacial flexible modular photovoltaic cell assembly

Abstract

The application discloses a kind of double-sided flexible modular photovoltaic cell components, including surface flexible layer and flexible back sheet are sequentially provided with upper encapsulation adhesive film layer, antireflection layer, upper EVA layer, transparent bottom layer, lower EVA layer, reflective back film layer from top to bottom between them, the lower surface of transparent bottom layer is provided with a plurality of recesses for placing battery component, the upper surface of lower EVA layer is provided with a plurality of inclined upper fixed blocks, the lower surface of transparent bottom layer is provided with a plurality of upper fixed slots for inserting upper fixed block, the inside wall of recess is all adhered with antireflection frame, the device is made of multilayer module, and is matched with multilayer EVA layer and a variety of antireflection layer, and the antireflection layer is wrapped battery component, the light utilization of battery component is maximally enhanced, and the irradiation angle in light utilization process is maximally increased by using semicircular antireflection block, the photoelectric conversion rate after increasing the above module is not less than 0.8 bag fraction, simple to use, prepare and install, low in cost, efficient and good in effect.

Description

Technical Field

[0001] This invention relates to a bifacial flexible modular photovoltaic cell module. Background Technology

[0002] Solar cells are generally not used directly as power sources. They are typically encapsulated into photovoltaic modules by glass, cross-linked films (EVA, PVB, PVF, etc.), and solar cells. Photovoltaic modules are a crucial component of photovoltaic power generation systems. In these systems, because photovoltaic modules operate outdoors year-round, the humid and high-temperature environment easily generates water vapor. If this moisture penetrates the module, the conductivity of the encapsulation material increases, leading to increased leakage current and surface polarization, known as the PID effect. The PID effect, also called potential-induced degradation, is caused by ion migration under high voltage between the encapsulation material, its upper and lower surfaces, and the solar cells and their grounded metal frame. This migration results in performance degradation, significantly reducing the module's output power. The exact cause of the PID effect remains unclear, but data from various photovoltaic module manufacturers and research institutions indicate that PID is related to the cells, glass, encapsulation film, temperature, humidity, and voltage.

[0003] Existing anti-PID technologies include: selecting special high-PID-resistant crosslinking films, adding an anti-PID film between glass cells, or adding additional electrical devices to eliminate induced potentials. Whether these technologies are truly effective remains to be verified, and their industrial application would undoubtedly significantly increase production costs. Therefore, it can be said that there is currently no effective low-cost anti-PID technology. It is clear that glass and the film have a definite relationship with the occurrence of PID. The glass used in photovoltaic modules is sodium-containing glass. Literature reports that alkali precipitation, mainly Na2O and MgO, occurs on the surface of silicate glass under high temperature and humidity conditions. However, reducing the sodium and magnesium ion content in the glass is very costly and not feasible. When the glass is replaced with quartz glass, no PID phenomenon was observed under the same testing conditions. Because solar cells are very fragile and easily oxidized when exposed to air for extended periods, they must be encapsulated with crosslinking films and photovoltaic glass. The crosslinking film, located between the solar cell and the glass, inadvertently acts as a medium for the migration of sodium and magnesium ions from the glass to the solar cell. Furthermore, the transparency of the cross-linked adhesive film also affects the power generation capacity of the module. Prolonged outdoor operation can degrade the performance of the cross-linked adhesive film, reducing its transparency and increasing the risk of macular degeneration, severely impacting the light absorption capacity of the cell surface. However, even the most transparent cross-linked adhesive film on the market (transmittance greater than 90%) can still absorb 10% of solar power, which cannot be effectively utilized by the solar cells. Additionally, the transmittance of photovoltaic glass is only around 90%, which also affects the power generation capacity of photovoltaic modules.

[0004] To improve the absorption capacity of photovoltaic cells for light in the 300-1100nm wavelength range of sunlight, an anti-reflective coating (anti-reflective film) is deposited on the surface of the glass during the manufacturing process, thereby increasing the transmittance of sunlight. CN105130205B provides a high-weather-resistant photovoltaic glass anti-reflective film that improves the light transmittance of the film under high humidity conditions while maintaining high hardness. Chinese patent CN104628265A discloses a multilayer broadband hydrophobic anti-reflective film. This composite film enhances the anti-reflection wavelength range in the visible light spectrum while also possessing certain hydrophobic properties.

[0005] Patent CN103943691A discloses a method for preparing a silica / titanium dioxide composite antireflective film using magnetron sputtering, achieving a transmittance of 98% in the 800-900nm light wave region, while simultaneously utilizing the photocatalytic self-cleaning function of titanium dioxide to achieve a self-cleaning effect. The methods described above all improve the film layer on photovoltaic glass and have shown some effectiveness. However, research on improving the transparency of EVA is limited. Current research on EVA focuses on enhancing its UV resistance and cross-linking properties without affecting transmittance. However, the transmittance of cross-linked EVA films remains around 90%, and their stability is not high. Therefore, a double-sided flexible modular photovoltaic cell module has emerged. Summary of the Invention

[0006] The purpose of this invention is to overcome the shortcomings of the prior art and provide a double-sided flexible modular photovoltaic cell module.

[0007] A double-sided flexible modular photovoltaic cell module includes a surface flexible layer and a flexible backsheet. The surface flexible layer and the flexible backsheet are, from top to bottom, provided with an upper encapsulating film layer, an anti-reflection layer, an upper EVA layer, a transparent bottom layer, a lower EVA layer, and a reflective backsheet layer. The lower surface of the transparent bottom layer has multiple grooves for placing the cell module. The upper surface of the lower EVA layer has multiple inclined upper fixing blocks. The lower surface of the transparent bottom layer has multiple upper fixing slots for inserting the upper fixing blocks. Anti-reflection frames are adhered to the inner walls of each groove.

[0008] As a further improvement, the lower surface of the anti-reflective layer is provided with multiple sliding grooves, and the upper surface of the upper EVA layer is provided with multiple anti-reflective blocks that slide in contact with the sliding grooves. By fixing the anti-reflective blocks in contact with the sliding grooves, the layers above the transparent bottom layer are fixed, which enhances the fixing effect and the stability after fixing, and improves the service life of the entire component.

[0009] As a further improvement, the sliding grooves are arranged in a vertical equidistant array, which effectively improves the stability and uniformity of stress after the antireflective layer and the lower EVA layer are fixed.

[0010] As a further improvement, the upper surface of the flexible backsheet is provided with multiple inclined lower fixing blocks, and the lower surface of the reflective back film layer is provided with multiple lower fixing grooves that are inserted into the lower fixing blocks. The inclined arrangement ensures the stability of the modular photovoltaic cell module in all directions.

[0011] As a further improvement, the lower fixing block, upper fixing block, lower fixing groove, and upper fixing groove are all arranged in an inclined equidistant array, and the inclined arrangement ensures the stability of the modular photovoltaic cell module in all directions.

[0012] As a further improvement, the depth of the groove is greater than the thickness of the battery assembly, ensuring the proper installation of the battery assembly and providing protection.

[0013] As a further improvement, the antireflective block is semi-circular in shape.

[0014] As a further improvement, the refractive index of the antireflection block, antireflection layer, and antireflection frame is not less than 1.70, effectively ensuring the light transmittance of the battery module in all directions. Beneficial effects

[0015] This device is composed of multiple modules, along with multiple EVA layers and various anti-reflection layers. The anti-reflection layers are wrapped around the battery module to maximize the light utilization rate of the battery module. The semi-circular anti-reflection block is used to maximize the illumination angle during light utilization. After adding the above modules, the photoelectric conversion efficiency is improved by no less than 0.8%. It is simple to use, prepare, and install, with low cost, high efficiency, and good effect.

[0016] This device uses grooves to fix the battery assembly, and the upper fixing block and upper fixing slot are inserted to form a better fixing effect, improving the stability of the battery assembly after it is fixed and installed.

[0017] This device achieves the fixation of each layer above the transparent bottom layer by sliding the anti-reflection block and the sliding groove, which enhances the fixation effect and the stability after fixation, and improves the service life of the entire module. The inclined arrangement ensures the stability of the modular photovoltaic cell module in all directions. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall structure of a photovoltaic cell module;

[0019] Figure 2 This is a schematic diagram of the three-dimensional structure of a photovoltaic cell module;

[0020] Figure 3 This is a schematic diagram of the transparent bottom layer structure;

[0021] Figure 4 This is a schematic diagram of the flexible backsheet structure;

[0022] 1. Surface flexible layer 2. Upper encapsulation film layer 3. Anti-reflective layer 4. Upper EVA layer 5. Lower EVA layer 6. Upper fixing groove 7. Reflective back film layer 8. Lower fixing block 9. Anti-reflective block 10. Flexible back sheet 11. Battery assembly 12. Anti-reflective frame 13. Transparent bottom layer. Detailed Implementation

[0023] To enhance understanding of the present invention, the present invention will be further described in detail below with reference to embodiments and accompanying drawings. These embodiments are only used to explain the present invention and do not constitute a limitation on the scope of protection of the present invention.

[0024] like Figures 1-4 As shown in a specific embodiment of the present invention, a double-sided flexible modular photovoltaic cell module includes a surface flexible layer 1, an upper encapsulating film layer 2, an anti-reflection layer 3, an upper EVA layer 4, a lower EVA layer 5, an upper fixing groove 6, a reflective back film layer 7, a lower fixing block 8, an anti-reflection block 9, a flexible back sheet 10, a cell module 11, an anti-reflection frame 12, and a transparent bottom layer 13.

[0025] A double-sided flexible modular photovoltaic cell module includes a surface flexible layer 1 and a flexible backsheet 10. The surface flexible layer 1 and the flexible backsheet 10 are, from top to bottom, provided with an upper encapsulating film layer 2, an anti-reflection layer 3, an upper EVA layer 4, a transparent bottom layer 13, a lower EVA layer 5, and a reflective backsheet layer 7. The lower surface of the transparent bottom layer 13 has multiple grooves for placing the cell module 11. The upper surface of the lower EVA layer 5 has multiple inclined upper fixing blocks. The lower surface of the transparent bottom layer 13 has multiple upper fixing slots 6 for inserting the upper fixing blocks. Anti-reflection frames 12 are adhered to the inner walls of each groove.

[0026] The lower surface of the anti-reflective layer 3 is provided with multiple sliding grooves, and the upper surface of the lower EVA layer 5 is provided with multiple anti-reflective blocks 9 that slide in the sliding grooves. By sliding the anti-reflective blocks 9 in the sliding grooves, the layers above the transparent bottom layer 13 are fixed, which enhances the fixing effect and the stability after fixing, and improves the service life of the entire component.

[0027] The sliding grooves are arranged in a vertical, equidistant array. This equidistant array arrangement effectively improves the stability of the antireflective layer 3 after it is fixed to the lower EVA layer and the uniformity of the stress after fixing.

[0028] The upper surface of the flexible backsheet 10 is provided with multiple inclined lower fixing blocks 8, and the lower surface of the reflective backsheet layer 7 is provided with multiple lower fixing grooves that are inserted into the lower fixing blocks 8. The inclined arrangement ensures the stability of the modular photovoltaic cell module 11 in all directions.

[0029] The lower fixing block 8, the upper fixing block, the lower fixing groove, and the upper fixing groove 6 are all arranged in an inclined equidistant array. The inclined arrangement ensures the stability of the modular photovoltaic cell module 11 in all directions.

[0030] The depth of the groove is greater than the thickness of the battery assembly 11, which ensures the proper installation of the battery assembly 11 and provides protection.

[0031] The anti-reflective block 9 is semi-circular in shape.

[0032] The refractive index of the antireflection block 9, the antireflection layer 3, and the antireflection frame 12 is not less than 1.70, which effectively ensures the light transmittance of the battery module 11 in all directions.

[0033] In use, a multi-layer modular structure is adopted to splice the battery modules. The splicing of the entire modular photovoltaic battery module is more stable through multiple directions of insertion.

[0034] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. 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.

[0035] The above description is merely a preferred embodiment of the present invention, and therefore should not be construed as limiting the scope of the present invention. All equivalent changes and modifications made in accordance with the scope of the patent and the contents of the specification should still fall within the scope of the present invention.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A bifacial flexible modular photovoltaic cell assembly comprising a surface flexible layer and a flexible back sheet, characterized in that, The surface flexible layer and the flexible back plate are sequentially provided with an upper encapsulation adhesive film layer, a transmittance increasing layer, an upper EVA layer, a transparent bottom layer, a lower EVA layer and a reflective back film layer from top to bottom, the lower surface of the transparent bottom layer is provided with a plurality of recesses for placing battery assemblies, the upper surface of the lower EVA layer is provided with a plurality of inclined upper fixing blocks, the lower surface of the transparent bottom layer is provided with a plurality of upper fixing grooves for inserting the upper fixing blocks, and the inner side walls of the recesses are all adhered with transmittance increasing frames; The lower surface of the transmittance increasing layer is provided with a plurality of sliding grooves, and the upper surface of the upper EVA layer is provided with a plurality of transmittance increasing blocks which are slidably connected with the sliding grooves; The sliding grooves are vertically and equidistantly arranged; The upper surface of the flexible back plate is provided with a plurality of inclined lower fixing blocks, and the lower surface of the reflective back film layer is provided with a plurality of lower fixing grooves which are inserted with the lower fixing blocks; The lower fixing blocks, the upper fixing blocks, the lower fixing grooves and the upper fixing grooves are all inclined and equidistantly arranged; The shape of the transmittance increasing blocks is semicircular.

2. A bifacial flexible modular photovoltaic cell assembly according to claim 1, characterized in that, The depth of the recesses is greater than the thickness of the battery assemblies.

3. A bifacial flexible modular photovoltaic cell assembly as claimed in claim 1, wherein, The refractive indexes of the transmittance increasing blocks, the transmittance increasing layer and the transmittance increasing frames are all not less than 1.70.

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