Photovoltaic module and preparation method thereof

Abstract

The invention relates to the technical field of photovoltaic power generation, in particular to a photovoltaic module and a preparation method thereof, and the preparation method comprises the steps: carrying out the heat treatment and annealing treatment of a front plate; and sequentially laminating the processed front plate, the first adhesive film layer, the battery piece, the second adhesive film layer and the back plate to obtain the photovoltaic module. According to the preparation method, the problems of warping and low production yield during assembly lamination can be solved, the obtained photovoltaic assembly has relatively good stiffness and impact resistance, and the service life of the photovoltaic assembly is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic power generation, and in particular to a photovoltaic module and a preparation method thereof. Background Art

[0002] In order to achieve the lightweight and bendable characteristics of the components, polymer composite materials are often used as packaging materials for component packaging. However, the thermal expansion coefficient of conventional polymer materials is relatively high compared to inorganic non-metallic glass, and there are obvious differences in the thermal performance parameters such as the thermal expansion coefficient and softening point of the materials between the layers. Therefore, under the conventional photovoltaic packaging conditions of 140-150℃ and 15-30min, deformation and softening are prone to occur, which can easily cause the packaging defect rate of lightweight components to be significantly higher than that of conventional packaging.

[0003] The prior art mentions the wrinkle problem that may exist when using a resin fiber layer as the front panel packaging material. The lamination wrinkle problem is solved by adjusting multiple parameters such as the pressurization time and the pressure value. However, compared with using a single film material as the packaging material, it cannot meet the impact performance requirements of existing lightweight components, and it is easy to increase the risk of hidden cracks or even fragments of the battery due to bending of the component during the process and installation. Summary of the invention

[0004] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the present invention provides a photovoltaic module and a preparation method thereof, which can solve the problems of warping and low production yield during module lamination, and the obtained photovoltaic module has good stiffness and impact resistance, thereby ensuring the service life of the photovoltaic module.

[0005] To this end, the first aspect of the present invention provides a method for preparing a photovoltaic module, comprising:

[0006] The front plate is subjected to heat treatment and annealing treatment;

[0007] The treated front plate, the first adhesive film layer, the battery sheet, the second adhesive film layer and the back plate are stacked in sequence to obtain the photovoltaic module.

[0008] The present invention significantly reduces the thermal shrinkage rate of the front plate in subsequent applications by heat-treating the front plate before lamination, thereby avoiding the warping and deformation problems of the finished component due to the different shrinkage rates of the materials at high temperatures. At the same time, the mechanical properties of the front plate material are improved by annealing treatment, which effectively avoids the stress cracking problem of the material during long-term use, and ensures the service life of the material and the effective service life of the photovoltaic component. Therefore, this solution effectively eliminates the problems of deformation and poor flatness of the finished product of the resin sheet after high-temperature lamination caused by softening point, deformation temperature and other reasons, and the processing process is concentrated on the material end without affecting the normal production process of the component, ensuring production efficiency, and eliminating the restrictions on the use of resin materials as front plate materials for photovoltaic lightweight component packaging.

[0009] According to an embodiment of the present invention, the temperature of the heat treatment is 140-170°C.

[0010] According to an embodiment of the present invention, the heat treatment time is 10-120s.

[0011] According to an embodiment of the present invention, the temperature of the annealing treatment is 80-120°C.

[0012] According to an embodiment of the present invention, the annealing treatment time is 10-120s.

[0013] According to an embodiment of the present invention, the preparation method further comprises: stacking the treated front panel, the first adhesive film layer, the battery cell, the second adhesive film layer and the back panel in sequence to obtain a component to be laminated, and laminating the component to be laminated to obtain the photovoltaic component.

[0014] According to an embodiment of the present invention, the lamination process sequentially includes a first lamination process and a second lamination process;

[0015] The first lamination process uses a pressure increasing method to perform lamination on the assembly to be laminated;

[0016] The second lamination process uses a constant pressure method to laminate the components to be laminated that have undergone the first lamination process.

[0017] According to an embodiment of the present invention, the first lamination process sequentially includes the following stages I, II and III:

[0018] Stage I: The pressurization pressure is -20kpa to -30kpa, and the pressurization time is 10-50s;

[0019] Stage II: The pressurization pressure is -10kpa~-20kpa, and the pressurization time is 10-50s;

[0020] Stage III: The pressurization pressure is -5kpa~-10kpa, and the pressurization time is 100-500s.

[0021] According to an embodiment of the present invention, the lamination temperature of the first lamination process is 85-110° C., and the lamination time is 5-15 min.

[0022] According to an embodiment of the present invention, the first lamination process further includes a vacuum treatment before the first stage, and the vacuum time is 100-400s.

[0023] According to an embodiment of the present invention, the pressing pressure in the second lamination process is -10 kPa to -5 kPa.

[0024] According to an embodiment of the present invention, the lamination temperature of the second lamination process is 120-150° C., and the lamination time is 6-15 minutes.

[0025] According to an embodiment of the present invention, the second lamination process further includes performing a vacuuming process before the pressurization, and the vacuuming time is 0-100s.

[0026] According to an embodiment of the present invention, the material of the front plate has a light transmittance greater than 90%, a softening point of 80-140°C, and a melting point of 170-300°C.

[0027] According to an embodiment of the present invention, the material of the front plate includes at least one of PC, PMMA, ABS and PET.

[0028] According to an embodiment of the present invention, the material of the first adhesive film layer and / or the second adhesive film layer independently includes at least one of EVA, POE, and PVB.

[0029] According to an embodiment of the present invention, the grammage of the first adhesive film layer and / or the second adhesive film layer is independently 320-480 g / m 2 .

[0030] According to an embodiment of the present invention, the material of the backplane includes at least one of CPC, KPC, TPC, and co-extruded polyolefin.

[0031] According to an embodiment of the present invention, the thickness of the front plate is 0.5-5 mm.

[0032] According to an embodiment of the present invention, the thickness of the first adhesive film layer is 0.4-2 mm.

[0033] According to an embodiment of the present invention, the thickness of the second adhesive film layer is 0.4-2 mm.

[0034] According to an embodiment of the present invention, the thickness of the back plate is 0.2-3 mm.

[0035] A second aspect of the present invention provides a photovoltaic module, which is obtained by the preparation method described in the first aspect.

[0036] Therefore, the photovoltaic module has good stiffness and impact resistance and a long service life.

[0037] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. DETAILED DESCRIPTION

[0038] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0039] It should be noted that the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. Further, in the description of the present invention, unless otherwise specified, the meaning of "plurality" is two or more.

[0040] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0041] In order to make the present invention more easily understood, certain technical and scientific terms are specifically defined below. Unless otherwise clearly defined elsewhere in this document, all other technical and scientific terms used herein have the meanings commonly understood by those skilled in the art to which the present invention belongs.

[0042] In this document, the terms “include” or “comprising” are open expressions, that is, including the contents specified in the present invention but not excluding other contents.

[0043] As used herein, the terms "optionally", "optional" or "optionally" generally mean that the subsequently described event or circumstance may but need not occur, and that the description includes instances where the event or circumstance occurs and instances where it does not.

[0044] According to an embodiment of the present invention, the present invention provides a method for preparing a photovoltaic module, comprising:

[0045] The front plate is subjected to heat treatment and annealing treatment;

[0046] The treated front plate, the first adhesive film layer, the battery sheet, the second adhesive film layer and the back plate are stacked in sequence to obtain the photovoltaic module.

[0047] The present invention significantly reduces the thermal shrinkage rate of the material in the subsequent application process by heat-treating the front plate, avoiding the warping and deformation problems of the finished component due to the different shrinkage rates of the materials at high temperatures. At the same time, the annealing treatment improves the mechanical properties of the front plate material, effectively avoiding the stress cracking problem of the material during long-term use, and ensuring the service life of the material and the effective service life of the photovoltaic module.

[0048] According to a specific embodiment of the present invention, the temperature of the heat treatment is 140-170°C. As some specific examples, the temperature of the heat treatment is 140°C, 150°C, 160°C, 170°C, etc. The time of the heat treatment is 10-120s. As some specific examples, the time of the heat treatment is 10s, 20s, 30s, 40s, 50s, 60s, 70s, 80s, 90s, 100s, 110s, 120s, etc.

[0049] According to a specific embodiment of the present invention, the temperature of the annealing treatment is 80-120°C. As some specific examples, the temperature of the annealing treatment is 80°C, 90°C, 100°C, 110°C, 120°C, etc. The time of the annealing treatment is 10-120s. As some specific examples, the time of the annealing treatment is 10s, 20s, 30s, 40s, 50s, 60s, 70s, 80s, 90s, 100s, 110s, 120s, etc.

[0050] According to a specific embodiment of the present invention, the preparation method further comprises: stacking the treated front panel, the first adhesive film layer, the battery cell, the second adhesive film layer and the back panel in sequence to obtain a component to be laminated, and laminating the component to be laminated to obtain the photovoltaic component.

[0051] According to a specific embodiment of the present invention, the lamination process sequentially includes a first lamination process and a second lamination process;

[0052] The first lamination process uses a pressure increasing method to perform lamination on the assembly to be laminated;

[0053] The second lamination process uses a constant pressure method to laminate the components to be laminated that have undergone the first lamination process.

[0054] According to a specific embodiment of the present invention, the first lamination process sequentially includes the following stages I, II and III:

[0055] Stage I: The pressurization pressure is -20kpa to -30kpa, and the pressurization time is 10-50s;

[0056] Stage II: The pressurization pressure is -10kpa~-20kpa, and the pressurization time is 10-50s;

[0057] Stage III: The pressurization pressure is -5kpa~-10kpa, and the pressurization time is 100-500s.

[0058] Specifically, the pressurization pressure of the first stage can be -30kpa, -29kpa, -28kpa, -27kpa, -26kpa, -25kpa, -24kpa, -23kpa, -22kpa, -21kpa, -20kpa, etc. The pressurization time can be 10s, 20s, 30s, 40s, 50s, etc.

[0059] Specifically, the pressurization pressure of the second stage may be -20 kpa, -19 kpa, -18 kpa, -17 kpa, -16 kpa, -15 kpa, -14 kpa, -13 kpa, -12 kpa, -11 kpa, -10 kpa, etc. The pressurization time may be 10 s, 20 s, 30 s, 40 s, 50 s, etc.

[0060] Specifically, the pressurization pressure of the stage III may be -10 kpa, -9 kpa, -8 kpa, -7 kpa, -6 kpa, -5 kpa, etc. The pressurization time may be 100 s, 200 s, 300 s, 400 s, 500 s, etc.

[0061] According to a specific embodiment of the present invention, the lamination temperature and time of the first lamination process are not particularly limited. As some specific examples, the lamination temperature of the first lamination process may be 85-110° C., such as 85° C., 90° C., 95° C., 100° C., 105° C., 110° C., etc. The time of the lamination process is 5-15 min, such as 5 min, 10 min, 15 min, etc.

[0062] According to a specific embodiment of the present invention, the first lamination process further includes a vacuum treatment before the first stage, and the time of the vacuum treatment is not particularly limited. As some specific examples, it can be 100-400s, such as 100s, 200s, 300s, 400s, etc. Specifically, the time of the first lamination process refers to the total time of the lamination process. When the lamination process includes a vacuum treatment, the time of the lamination process includes a pressurization time and a vacuum treatment time.

[0063] According to a specific embodiment of the present invention, the pressure applied in the second lamination process is not particularly limited. Specifically, the pressure applied in the second lamination process may be -20 kpa to -5 kpa, such as -20 kpa, -15 kpa, -10 kpa, -5 kpa, etc.

[0064] According to a specific embodiment of the present invention, the lamination temperature and time of the second lamination process are not particularly limited. As some specific examples, the lamination temperature of the second lamination process is 120-150° C., such as 120° C., 130° C., 140° C., 150° C., etc. The time of the second lamination process is 6-15 min, such as 6 min, 7 min, 8 min, 9 min, 10 min, 11 min, 12 min, 13 min, 14 min, 15 min, etc.

[0065] According to a specific embodiment of the present invention, the second lamination process further includes a vacuum treatment before pressurization, and the time of the vacuum treatment is not particularly limited. As some specific examples, it can be 0-100s. Specifically, the time of the second lamination process refers to the total time of the lamination process. When the lamination process includes a vacuum treatment, the time of the lamination process includes the pressurization time and the vacuum treatment time.

[0066] According to a specific embodiment of the present invention, the light transmittance of the material of the front plate is greater than 90%. As some specific examples, the light transmittance of the material of the front plate may be 91%, 92%, 93%, 94%, 95%, 96%, etc. The softening point of the material of the front plate is 80-140°C. As some specific examples, the softening point of the material of the front plate may be 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, etc. The melting point of the material of the front plate is 170-300°C. As some specific examples, the melting point of the material of the front plate may be 170°C, 200°C, 250°C, 300°C, etc.

[0067] Specifically, the type of the front panel material is not particularly limited. Some specific examples include but are not limited to PC (polycarbonate), PMMA (polymethyl methacrylate), ABS (a terpolymer of three monomers: acrylonitrile (A), butadiene (B), and styrene (S)), and PET (polyethylene terephthalate).

[0068] According to a specific embodiment of the present invention, the types of materials of the first adhesive film layer and the second adhesive film layer are not particularly limited. Some specific examples include but are not limited to EVA (ethylene-vinyl acetate copolymer), POE (thermoplastic elastomer of in-situ polymerization of ethylene and octene), and PVB (polyvinyl butyral).

[0069] According to a specific embodiment of the present invention, the gram weight of the first adhesive film layer and the second adhesive film layer is not particularly limited. As some specific examples, the gram weight of the first adhesive film layer and the second adhesive film layer is independently 320-480 g / m 2 , for example 320g / m 2 , 330g / m 2 , 340g / m 2 , 350g / m 2 , 360g / m 2 , 370g / m 2 , 380g / m 2 , 390g / m 2 , 400g / m 2 , 410g / m 2 , 420g / m 2 , 430g / m 2 , 440g / m 2 , 450g / m 2 , 460g / m 2 , 470g / m 2 , 480g / m 2 The crosslinking degree of the adhesive film layer after lamination is 70%-90%, such as 70%, 75%, 80%, 85%, 90%, etc.

[0070] According to a specific embodiment of the present invention, the type of the backplane material is not particularly limited. Some specific examples include but are not limited to CPC (double-sided coated photovoltaic backplane), KPC (PVDF type single-sided coated backplane), TPC (PVF type single-sided coated backplane), and co-extruded polyolefins (such as co-extruded polyethylene backplane).

[0071] According to a specific embodiment of the present invention, the thickness of the front plate is not particularly limited. As some specific examples, the thickness of the front plate is 0.5-5 mm. For example, the thickness of the front plate is 0.5 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, etc.

[0072] According to an embodiment of the present invention, the thickness of the first adhesive film layer is not particularly limited. As some specific examples, the thickness of the first adhesive film layer is 0.4-2 mm, for example, the thickness of the first adhesive film layer is 0.4 mm, 1 mm, 1.5 mm, 2 mm, etc.

[0073] According to an embodiment of the present invention, the thickness of the second adhesive film layer is not particularly limited. As some specific examples, the thickness of the second adhesive film layer is 0.4-2 mm, for example, the thickness of the second adhesive film layer is 0.4 mm, 1 mm, 1.5 mm, 2 mm, etc.

[0074] According to an embodiment of the present invention, the thickness of the backplane is not particularly limited. As some specific examples, the thickness of the backplane is 0.2-3 mm, for example, the thickness of the backplane is 0.2 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, etc.

[0075] According to an embodiment of the present invention, a second aspect of the present invention provides a photovoltaic module, and the photovoltaic module is obtained by the preparation method described in the first aspect.

[0076] Therefore, the photovoltaic module has good stiffness and impact resistance and a long service life.

[0077] The scheme of the present invention will be explained below in conjunction with the embodiments. It will be appreciated by those skilled in the art that the following embodiments are only used to illustrate the present invention and should not be considered as limiting the scope of the present invention. Where specific techniques or conditions are not indicated in the embodiments, the techniques or conditions described in the literature in this area or the product specifications are used. The reagents or instruments used are not indicated by the manufacturer and are all conventional products that can be obtained commercially.

[0078] Example 1

[0079] (1) The front plate material is 2mm resin PMMA plate, the heat treatment process is 150℃, the treatment time is 30s; the annealing process condition is 100℃, the treatment time is 40s;

[0080] (2) The layers are stacked in the order of PMMA board / EVA film / cell / EVA film / conventional CPC backplane; and tape is used to fix each layer of material in the corresponding position. The weight of the EVA film is 460g / m 2 ;

[0081] (3) Two-stage lamination method is used during the lamination process:

[0082] The temperature of the first lamination stage was set at 90°C, and the pressure parameters were set in three stages, namely -20kpa, -10kpa, and -5kpa. The corresponding pressurization times were 20s, 20s, and 200s, respectively. The vacuuming time was 300s, and the total lamination time was 540s.

[0083] The temperature of the second lamination stage was set to 135°C, the lamination time was 300s, the pressure was set to -5kPa, and the vacuum time was set to 20s.

[0084] Example 2

[0085] (1) The front plate material is 2mm resin PC sheet, the heat treatment process is 150℃, the treatment time is 30s; the annealing process condition is 100℃, the treatment time is 30s;

[0086] (2) Stack the layers in the order of PC board / EVA film / cell / EVA film / conventional CPC backsheet; and use tape to fix each layer of material in the corresponding position. The weight of the EVA film is 460g / m 2 ;

[0087] (3) Two-stage lamination method is used during the lamination process:

[0088] The temperature of the first lamination stage was set at 90°C, and the pressure parameters were set in three stages, namely -20kpa, -10kpa, and -5kpa. The corresponding pressurization times were 20s, 20s, and 400s, respectively. The vacuuming time was 300s, and the total lamination time was 740s.

[0089] The temperature of the second lamination stage was set to 135°C, the lamination time was 300s, the pressure was set to -5kPa, and the vacuum time was set to 20s.

[0090] Example 3

[0091] (1) The front plate material is 2mm resin PC sheet, the heat treatment process is 150℃, the treatment time is 30s; the annealing process condition is 100℃, the treatment time is 30s;

[0092] (2) Stack the layers in the order of PC board / EVA film / cell / EVA film / conventional CPC backsheet; and use tape to fix each layer of material in the corresponding position. The weight of the EVA film is 460g / m 2 ;

[0093] (3) Two-stage lamination method is used during the lamination process:

[0094] The temperature of the first lamination stage was set at 90°C, and the pressure parameters were set in three stages, namely -25kpa, -15kpa, and -5kpa. The corresponding pressurization times were 10s, 20s, and 210s, respectively. The vacuuming time was 300s, and the total lamination time was 540s.

[0095] The temperature of the second lamination stage was set to 135°C, the lamination time was 350s, the pressure was set to -5kPa, and the vacuum time was set to 15s.

[0096] Comparative Example 1

[0097] (1) The front panel material is 2mm resin PC sheet, which is stacked in the order of PC sheet / EVA film / cell / EVA film / conventional CPC back panel; and tape is used to fix each layer of material in the corresponding position. The weight of the EVA film is 460g / m 2 ;

[0098] (2) Two-stage lamination method is used during the lamination process:

[0099] The temperature of the first lamination stage was set at 90°C, and the pressure parameters were set in three stages, namely -25kpa, -15kpa, and -5kpa. The corresponding pressurization times were 10s, 20s, and 260s, respectively. The vacuuming time was 300s, and the total lamination time was 590s.

[0100] The temperature of the second lamination stage was set to 135°C, the lamination time was 350s, the pressure was set to -5kPa, and the vacuum time was set to 20s.

[0101] Comparative Example 2

[0102] (1) The front panel material is 2mm resin PC sheet, the heat treatment process is 150℃, and the treatment time is 30s;

[0103] (2) Stack the layers in the order of PC board / EVA film / cell / EVA film / conventional CPC backsheet; and use tape to fix each layer of material in the corresponding position. The weight of the EVA film is 460g / m 2 ;

[0104] (3) During the lamination process, a one-stage lamination method was adopted, the lamination temperature was set to 135°C, the lamination time was 840s, the pressure was set to -60kpa / -40kpa / -20kpa, and the vacuum time was set to 60s.

[0105] Test example:

[0106] The appearance and impact resistance of the photovoltaic modules prepared in the embodiment and the comparative example were tested respectively, and the results are shown in Table 1:

[0107] Table 1

[0108] Experimental groups Appearance Shock resistance Embodiment 1 No warping, no shrinkage Passed 25mm ice ball test Embodiment 2 No warping, no shrinkage Passed 25mm ice ball test Embodiment 3 No warping, no shrinkage Passed 25mm ice ball test Comparative Example 1 There is warping, shrinkage, and irregularity Passed 25mm ice ball test Comparative Example 2 There is warping, shrinkage, and irregularity 25mm ice ball test material cracking

[0109] The results show that the preparation method of the photovoltaic module provided by the present invention can ensure that the material does not undergo obvious thermal shrinkage during the lamination process, and the module does not have warping problems after lamination. At the same time, the annealing process releases the internal stress of the material, and the finished product has good mechanical properties during subsequent use, and is not prone to cracking and poor impact resistance.

[0110] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0111] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A method for preparing a photovoltaic module, characterized in that: include: The front plate is subjected to heat treatment and annealing treatment; The treated front plate, the first adhesive film layer, the battery sheet, the second adhesive film layer and the back plate are stacked in sequence to obtain the photovoltaic module.

2. The preparation method according to claim 1, characterized in that: The temperature of the heat treatment is 140-170°C; Optionally, the heat treatment time is 10-120s.

3. The preparation method according to claim 1, characterized in that: The annealing temperature is 80-120°C; Optionally, the annealing treatment time is 10-120s.

4. The preparation method according to claim 1, characterized in that: The preparation method further comprises: stacking the treated front plate, the first adhesive film layer, the battery sheet, the second adhesive film layer and the back plate in sequence to obtain a component to be laminated, and laminating the component to be laminated to obtain the photovoltaic component.

5. The preparation method according to claim 4, characterized in that: The lamination process sequentially includes a first lamination process and a second lamination process; The first lamination process uses a pressure increasing method to perform lamination on the assembly to be laminated; The second lamination process uses a constant pressure method to laminate the components to be laminated that have undergone the first lamination process.

6. The preparation method according to claim 5, characterized in that: The first lamination process includes the following stages I, II and III in sequence: Stage I: The pressurization pressure is -20kpa to -30kpa, and the pressurization time is 10-50s; Stage II: The pressurization pressure is -10kpa~-20kpa, and the pressurization time is 10-50s; Stage III: The pressurization pressure is -5kpa~-10kpa, and the pressurization time is 100-500s; Optionally, the lamination temperature of the first lamination treatment is 85-110° C., and the lamination treatment time is 5-15 min; Optionally, the first lamination process further comprises a vacuum treatment before the first stage, and the vacuum time is 100-400s.

7. The preparation method according to claim 5, characterized in that: The pressurizing pressure in the second lamination process is -20 kPa to -5 kPa; Optionally, the lamination temperature of the second lamination treatment is 120-150° C., and the lamination treatment time is 6-15 min; Optionally, the second lamination process further comprises a vacuuming process before the pressurization, and the vacuuming time is 0-100s.

8. The preparation method according to claim 1, characterized in that: The material of the front plate has a light transmittance greater than 90%, a softening point of 80-140°C, and a melting point of 170-300°C; Optionally, the material of the front plate includes at least one of PC, PMMA, ABS, and PET; Optionally, the material of the first adhesive film layer and / or the second adhesive film layer independently includes at least one of EVA, POE, and PVB; Optionally, the first adhesive film layer and / or the second adhesive film layer independently have a grammage of 320-480 g / m 2 ; Optionally, the material of the back sheet includes at least one of CPC, KPC, TPC, and co-extruded polyolefin.

9. The preparation method according to claim 1, characterized in that: The thickness of the front plate is 0.5-5 mm; Optionally, the thickness of the first adhesive film layer is 0.4-2 mm; Optionally, the thickness of the second adhesive film layer is 0.4-2 mm; Optionally, the back plate has a thickness of 0.2-3 mm.

10. A photovoltaic module, characterized in that: The photovoltaic module is obtained by the preparation method according to any one of claims 1 to 9.