Double-glass photovoltaic module

Abstract

The embodiment of the invention provides a double-glass photovoltaic module which comprises front plate glass, a solar cell and back plate glass which are arranged in a laminated mode, the solar cell is located between the front plate glass and the back plate glass, and a first infrared reflection film is further arranged between the solar cell and the back plate glass. The first infrared reflecting film is arranged on the surface of the back plate glass, so that infrared light in the photovoltaic module can be reflected back to the battery piece by the first infrared reflecting film to be reused, and the photoelectric conversion efficiency is improved; the double-glass photovoltaic module provided by the invention can effectively solve the problem of insufficient light utilization rate of the existing double-glass photovoltaic module.

Description

Technical Field

[0001] The invention relates to the technical field of photovoltaic manufacturing, and in particular to a double-glass photovoltaic module. Background Art

[0002] Currently, double-glass photovoltaic modules are widely used.

[0003] However, because the reflectivity of photovoltaic backplane glass is not as good as that of photovoltaic backplane, the light utilization rate is insufficient, making the power of double-glass photovoltaic modules with the same efficiency photovoltaic cells 3 to 5W higher than that of single-glass photovoltaic modules, affecting the photoelectric conversion efficiency of double-glass photovoltaic modules. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a double-glass photovoltaic module to solve the problem of insufficient light utilization rate of the existing double-glass photovoltaic modules.

[0005] In order to solve the above problems, the present invention is achieved through the following technical solutions:

[0006] The present invention proposes a double-glass photovoltaic module, which includes a stacked front glass, solar cells and back glass, wherein the solar cells are located between the front glass and the back glass, and a first infrared reflective film is also arranged between the solar cells and the back glass.

[0007] Furthermore, in the double-glass photovoltaic module, the reflection bandwidth of the first infrared reflection film is 750nm to 1200mm.

[0008] Furthermore, in the double-glass photovoltaic module, the first infrared reflective film is composed of a first film layer and a second film layer that are alternately laminated, and the refractive index of the first film layer is greater than the refractive index of the second film layer.

[0009] Furthermore, in the double-glass photovoltaic module, the surfaces on both sides of the first infrared reflective film are the first film layer.

[0010] Furthermore, in the double-glass photovoltaic module, the first film layer is composed of titanium dioxide, and the second film layer is composed of silicon dioxide.

[0011] Furthermore, in the double-glass photovoltaic module, the thickness of the first film layer and the second film layer are both 50-150 nm.

[0012] Furthermore, the double-glass photovoltaic module also includes an anti-reflection layer, and the anti-reflection layer is arranged on a side of the back panel glass away from the solar cell.

[0013] Furthermore, the double-glass photovoltaic module also includes a second infrared reflective film, and the second infrared reflective film is arranged between the back panel glass and the anti-reflection layer.

[0014] Furthermore, in the double-glass photovoltaic module, the second infrared reflective film has the same structure as the first infrared reflective film.

[0015] The present invention also provides a photovoltaic laminated glass, which includes the double-glass photovoltaic module as described above.

[0016] Compared with the prior art, the embodiments of the present invention have the following advantages:

[0017] In the embodiment of the present invention, the double-glass photovoltaic module provided includes a front plate glass, a solar cell and a back plate glass which are stacked, the solar cell is located between the front plate glass and the back plate glass, and a first infrared reflection film is also arranged between the solar cell and the back plate glass. Because the first infrared reflection film is arranged on the surface of the back plate glass, it can be used to reflect the infrared light in the photovoltaic module back to the cell for reuse, thereby improving the photoelectric conversion efficiency; therefore, the double-glass photovoltaic module provided by the present invention can effectively solve the problem of insufficient light utilization rate of the existing double-glass photovoltaic module.

[0018] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is a schematic diagram of the structure of a double-glass photovoltaic module provided by an embodiment of the present invention;

[0020] Figure 2 It is a schematic diagram of the structure of the first infrared reflective film provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] The applicant of the present invention has found that the reflectivity of photovoltaic backplane glass is not as good as that of photovoltaic backplane, resulting in the power of double-glass photovoltaic modules with the same efficiency photovoltaic cells being 3 to 5W higher than that of single-glass photovoltaic modules. This is mainly because the front incident light shines on the cell, and the infrared light in the wavelength range of 750 to 1200nm directly passes through the cell and the backplane glass and leaves the module, resulting in insufficient light utilization and affecting the photoelectric conversion efficiency of the module.

[0023] In order to solve the above problems, the embodiment of the present invention provides a double-glass photovoltaic module, such as Figure 1As shown, it includes a stacked front glass 11, a solar cell 12 and a back glass 13, wherein the solar cell 12 is located between the front glass 11 and the back glass 13, and a first infrared reflective film 14 is also arranged between the solar cell 12 and the back glass 13.

[0024] Among them, because a first infrared reflective film 14 is arranged on the surface of the back glass 13, it can be used to reflect the infrared light in the photovoltaic module back to the battery cell for repeated use, so as to achieve the purpose of improving the photoelectric conversion efficiency; therefore, the double-glass photovoltaic module provided by the present invention can effectively solve the problem of insufficient light utilization rate of existing double-glass photovoltaic modules.

[0025] In addition, since the first infrared reflective film 14 can reflect infrared rays entering the component from the back, the temperature rise of the component caused by radiation from the ground can be alleviated.

[0026] The double-glass photovoltaic module provided in the embodiment of the present invention is suitable for high-altitude environments, for example, it can be installed as photovoltaic glass in high-rise buildings.

[0027] Optionally, in one embodiment, the double-glass photovoltaic module provided in the embodiment of the present invention has a reflection bandwidth of the first infrared reflection film 14 of 750nm to 1200mm. Among them, because the incident light from the front is mainly irradiated on the battery, the infrared light in the wavelength range of 750 to 1200nm directly passes through the battery and the back glass 13 and leaves the module, resulting in insufficient light utilization, affecting the photoelectric conversion efficiency of the double-glass photovoltaic module; the reflection bandwidth of the first infrared reflection film 14 arranged on the surface of the back glass 13 in the embodiment of the present invention is 750nm to 1200mm, so the first infrared reflection film 14 can be used to reflect the infrared light of this wavelength in the photovoltaic module back to the battery sheet for reuse, thereby effectively improving the photoelectric conversion efficiency.

[0028] In practical applications, the reflectivity of the first infrared reflective film 14 in the above-mentioned wavelength band is 82.28%.

[0029] Optionally, in one embodiment, Figure 2 As shown, the first infrared reflective film 14 is composed of a first film layer 141 and a second film layer 142 that are alternately laminated, and the refractive index of the first film layer 141 is greater than the refractive index of the second film layer 142. By alternately arranging two film layers with different refractive indices, infrared light can be reflected more effectively, thereby improving the photoelectric conversion efficiency of the photovoltaic module.

[0030] Optionally, in one embodiment, the surfaces on both sides of the first infrared reflective film 14 are the first film layer 141, that is, a high refractive index film layer is provided on both sides of the first infrared reflective film 14, so that a higher infrared reflectivity can be obtained, and the utilization rate of infrared light in the wavelength range of 750 to 1200 nm can be further improved.

[0031] Optionally, in one embodiment, the first film layer 141 is composed of titanium dioxide, and the second film layer 142 is composed of silicon dioxide, wherein silicon dioxide is used as a low refractive index medium, specifically rutile phase, and the greater the refractive index difference between silicon dioxide and the titanium dioxide film layer, the better.

[0032] In this embodiment, the first film layer 141 is a titanium dioxide film, and the second film layer 142 is a silicon dioxide film, so the first infrared reflective film 14 can be prepared by a sol-gel method and a spin coating process.

[0033] Among them, the sol-gel method uses liquid chemical reagents to prepare metal inorganic salts or metal alkoxide precursors, the precursors are dissolved in a solvent to form a uniform solution, and an appropriate amount of coagulant is added to hydrolyze, alcoholyze or polymerize the salt to form a uniform and stable sol system. After a long period of placement (aging) or drying treatment, the solute is polymerized and gelled, and the gel is then dried and calcined to remove the organic components to finally obtain inorganic nanomaterials.

[0034] Depending on the raw materials, the sol-gel method can generally be divided into an inorganic salt sol-gel method and a metal alkoxide hydrolysis method.

[0035] Among them, in the inorganic salt sol-gel method, the preparation of sol is to control the precipitation process of inorganic salts so that the generated particles do not agglomerate into large particles but form precipitation, and directly obtain sol; or first precipitate some or all components with appropriate precipitants, and then disperse the originally agglomerated precipitation particles into colloidal particles after decoagulation. The formation of sol is mainly completed by the hydrolysis of inorganic salts. The reaction formula is as follows:

[0036] M n+ +H2O→M(OH) n +nH + (1-1)

[0037] Among them, the metal alkoxide hydrolysis method usually uses metal organic alkoxide as raw material to prepare sol through hydrolysis and polycondensation reaction. First, the metal alkoxide is dissolved in an organic solvent, and the following reaction will occur when water is added:

[0038] Hydrolysis reaction:

[0039] M(OR) m +H2O→M(OR) m-n (OH) n +nH + +nHOR (1-2)

[0040] Polycondensation reaction:

[0041] 2M(OR) m-n (OH)n →[M(OR) m-n (OH) n-1 ]2O+H2O (1-3)

[0042] Overall reaction formula:

[0043] M(OR) m +H2O→MO2+mHOR (1-4)

[0044] In the formula, M is a metal, and R is an organic group such as an alkyl group. The organic solution is removed by heating to obtain a metal oxide material.

[0045] In practical applications, the sol-gel method for preparing inorganic nanomaterials includes steps a to e.

[0046] a. Preparation of homogeneous solution

[0047] A homogeneous solution comprising alkoxide and water is prepared to ensure that the hydrolysis reaction of the alkoxide proceeds at the molecular level.

[0048] b. Preparation of sol

[0049] The first method is to first precipitate some or all of the components with an appropriate precipitant, and then disperse the originally agglomerated precipitated particles into original particles through decoagulation.

[0050] The second method: by strictly controlling the precipitation process with the same salt solution, the initially formed particles will not agglomerate into large particles and precipitate, thus directly obtaining a colloidal solution.

[0051] c. Gelation process

[0052] The polymer or particle aggregates formed by the polycondensation reaction grow into small particle clusters, which gradually connect to form a three-dimensional continuous solid network of particle clusters across the whole. During the aging process, the colloidal particles aggregate to form a gel. Since the liquid phase is wrapped in the solid phase skeleton, the entire system loses its activity. As the colloidal particles gradually form a network structure, the sol also changes from a Newton body to a Bingham body with obvious thixotropy.

[0053] d. Drying of gel

[0054] A large amount of solvent and water are contained in the wet gel. The physically adsorbed water and organic solvent and chemically adsorbed hydroxyl or alkoxy residues in the wet gel are removed by drying.

[0055] e. Heat treatment of xerogel

[0056] The purpose of heat treatment is to eliminate the pores in the dry gel so that the phase composition and microstructure of the finished product meet the performance requirements of the product.

[0057] During the heating process, the dry gel first removes the water and alcohol adsorbed on the surface at low temperature; among them, the alkoxy groups are oxidized at 265-300°C, and the hydroxyl groups in the structure are removed above 300°C. Since the heat treatment is accompanied by a large volume shrinkage and the release of various gases such as CO2, H2O, ROH, etc., the heating rate should not be too fast.

[0058] (1) Preparation of titanium dioxide film

[0059] Titanium dioxide thin films were prepared by spin coating in air atmosphere with SiO2 / Si(100) as substrate and the spin coating was carried out at 2000 rmin in air atmosphere. - After spinning at a speed of 1 for 30 seconds, the wet chemical film was kept at 100°C for 10 minutes to gel; then it was placed in a sintering furnace and sintered along a temperature rising curve to form a titanium dioxide film.

[0060] Among them, the speed of the coating machine during the coating process has a direct impact on the thickness of the film. - 1, the capillary force combining the sol and the substrate is moderate, and the amount of sol particles attached to the substrate is appropriate, which is suitable for forming the required film thickness.

[0061] (2) Preparation of silicon dioxide film

[0062] TEOS, H2O, and NH3·H2O were mixed in a molar ratio of 1:75:5, and stirred at room temperature until completely uniform. The sol system was heated at 70 degrees Celsius and concentrated to a volume of 35% of the original volume. Finally, a 5.5wt% PVA aqueous solution was added, and the mixture was stirred uniformly and filtered using a slow filter paper to obtain a TEOS sol.

[0063] The prepared precursor sol is used to prepare a SiO2 wet chemical film, which is then heat-treated in air at 100 degrees Celsius to volatilize the solvent, water and other organic matter in the wet chemical film; after the wet chemical film is heat-treated in an air atmosphere, it is transferred to a muffle furnace and subjected to reduction heat treatment at 500 degrees Celsius to prepare a silicon dioxide film.

[0064] In the embodiment of the present invention, the first film layer 141 may be provided with multiple layers, and the second film layer 142 has one layer less than the first film layer 141. Optionally, the first infrared reflective film 14 includes 2 first film layers 141 and 1 second film layer 142; optionally, the first infrared reflective film 14 includes 8 first film layers 141 and 7 second film layers 142.

[0065] Optionally, in one embodiment, the thickness of the first film layer 141 is 50 to 150 nm, for example, it can be one of 50 nm, 70 nm, 90 nm, 110 nm, 130 nm, 150 nm or any two of the range values; the thickness of the second film layer 142 is 50 to 150 nm, for example, it can be one of 50 nm, 70 nm, 90 nm, 110 nm, 130 nm, 150 nm or any two of the range values. In practical applications, the thickness of each first film layer 141 is different, and the thickness of each second film layer 142 is also different.

[0066] Optionally, in one embodiment, the double-glass photovoltaic module provided in the embodiment of the present invention further includes an anti-reflection layer 15, which is disposed on the side of the back glass 13 away from the solar cell 12, that is, disposed on a layer in contact with the external environment, and can enhance the anti-reflection effect of the double-glass photovoltaic module. Optionally, the anti-reflection layer 15 may include a silicon nitride film layer, a silicon oxynitride film layer, and a silicon oxide film layer, and the silicon nitride film layer, the silicon oxynitride film layer, and the silicon oxide film layer are sequentially disposed from the inside to the outside on the side of the back glass 13 away from the solar cell 12.

[0067] Optionally, in one embodiment, the double-glass photovoltaic module provided in the embodiment of the present invention further includes a second infrared reflective film 16, which is disposed between the back glass 13 and the anti-reflection layer 15, and can reflect the infrared light in the photovoltaic module that is not reflected back to the cell by the first infrared reflective film 14 back to the cell for reuse, further improving the photoelectric conversion efficiency, and at the same time, can better reflect the infrared light entering the module from the back, and can alleviate the temperature rise of the module caused by radiation from the ground. In addition, because the second infrared reflective film 16 is disposed between the back glass 13 and the anti-reflection layer 15, the anti-reflection layer 15 can be effectively used to protect it and avoid erosion by the external environment.

[0068] Experiments show that, taking a 72-panel double-glass photovoltaic module as an example, compared with a 72-panel double-glass photovoltaic module that does not have a first infrared anti-reflection film on the back glass, the double-glass photovoltaic module provided by the embodiment of the present invention can increase its power by up to 4.12W.

[0069] In summary, in this embodiment, the double-glass photovoltaic module provided includes a front glass 11, a solar cell 12 and a back glass 13 which are stacked, the solar cell 12 is located between the front glass 11 and the back glass 13, and a first infrared reflection film 14 is also provided between the solar cell 12 and the back glass 13. Because the first infrared reflection film 14 is provided on the surface of the back glass 13, the first infrared reflection film 14 can be used to reflect infrared light in the photovoltaic module back to the cell for reuse, thereby improving the photoelectric conversion efficiency; therefore, the double-glass photovoltaic module provided by the present invention can effectively solve the problem of insufficient light utilization of the existing double-glass photovoltaic module.

[0070] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they are aware of the basic creative concept. Therefore, the claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.

[0071] The double-glass photovoltaic module provided by the present invention is introduced in detail above. Specific examples are used in this article to illustrate the principle and implementation mode of the present invention. The description of the above embodiments is only used to help understand the method of the present invention and its core idea. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation mode and application scope. In summary, the content of this specification should not be understood as a limitation on the present invention.

Claims

1. A double-glass photovoltaic module, characterized in that: It comprises a front plate glass, a solar cell sheet and a back plate glass which are stacked, wherein the solar cell sheet is located between the front plate glass and the back plate glass, and a first infrared reflection film is also arranged between the solar cell sheet and the back plate glass.

2. The double-glass photovoltaic module according to claim 1, characterized in that: The reflection bandwidth of the first infrared reflection film is 750nm-1200mm.

3. The double-glass photovoltaic module according to claim 1, characterized in that: The first infrared reflective film is composed of a first film layer and a second film layer that are alternately laminated, and the refractive index of the first film layer is greater than the refractive index of the second film layer.

4. The double-glass photovoltaic module according to claim 3, characterized in that: The surfaces on both sides of the first infrared reflective film are the first film layers.

5. The double-glass photovoltaic module according to claim 3, characterized in that: The first film layer is made of titanium dioxide, and the second film layer is made of silicon dioxide.

6. The double-glass photovoltaic module according to claim 5, characterized in that: The thickness of the first film layer is 50-150 nm, and the thickness of the second film layer is 50-150 nm.

7. The double-glass photovoltaic module according to claim 1, characterized in that: It also includes an anti-reflection layer, which is arranged on a side of the back panel glass away from the solar cell sheet.

8. The double-glass photovoltaic module according to claim 7, characterized in that: It also includes a second infrared reflective film, which is arranged between the back panel glass and the anti-reflection layer.

9. The double-glass photovoltaic module according to claim 7, characterized in that: The second infrared reflective film has the same structure as the first infrared reflective film.

10. The double-glass photovoltaic module according to claim 3, characterized in that: The first infrared reflective film includes 8 first film layers and 7 second film layers.

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