Pretreatment device and pretreatment method for packaging adhesive film and pretreated packaging adhesive film

Abstract

The invention provides a pretreatment device of a packaging adhesive film, the pretreatment device comprises a first mold, the first mold comprises a flat-plate-shaped first body and a plurality of first protruding parts arranged in an array mode, the height of the first protruding parts is larger than or equal to 0.01 mm and smaller than or equal to 0.4 mm, and the first body is provided with a plurality of second protruding parts; the distance between every two adjacent first protruding parts is larger than or equal to 0.01 mm and smaller than or equal to 5 mm, and the distance between the first protruding part located on the edge of the first mold and the edge of the first mold is larger than or equal to 5 mm. The invention further provides a pretreatment method of the packaging adhesive film and the pretreated packaging adhesive film. According to the pretreatment device and the pretreatment method, the packaging adhesive film can be pretreated before the photovoltaic module is assembled, and the pretreated packaging adhesive film has a surface structure matched with a battery string or a battery piece to be assembled. The pretreatment device and the pretreatment method have wide applicability and can be suitable for packaging adhesive films of all structures.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular to a pretreatment device and method for a packaging adhesive film, and a pretreated packaging adhesive film. Background Art

[0002] The photovoltaic module 100 is generally composed of Figure 1 The front substrate 11, packaging film 12, battery string 13, packaging film 12 and back substrate 14 shown are obtained after lamination, wherein the battery string 13 includes components such as welding strips and battery cells, the thickness of the battery string 13 is thicker than the area between adjacent battery strings, and the packaging film 12 is usually a flat shape with uniform thickness everywhere. Therefore, due to the height difference generated above, the battery cells are prone to hidden cracks or even splits during the lamination process of the photovoltaic module, resulting in low yield of the photovoltaic module and increased production costs.

[0003] In the related art, by setting a corresponding concave-convex structure on the surface of the encapsulation film during the production process of the encapsulation film, the height difference after the components of the photovoltaic module are stacked is eliminated, so that the overall thickness of the photovoltaic module is consistent before lamination, thereby reducing hidden cracks or splits of the battery cells during the lamination process.

[0004] However, the prior art is to process the encapsulation film during its preparation. Since there are various types or sizes of cells and cell strings in photovoltaic modules, an encapsulation film with a concave-convex structure can only be applied to photovoltaic modules of corresponding structures, and cannot be used in photovoltaic modules of different types and sizes, which will undoubtedly increase the procurement and management costs of materials. Summary of the invention

[0005] In order to solve the above problems, we provide a pretreatment device for packaging film, which can pretreatment ordinary packaging film for the packaged photovoltaic components, so that the pretreated packaging film has a concave-convex structure that can match the packaged battery string or battery cell.

[0006] To achieve the above objectives, the technical solutions adopted in this application are as follows:

[0007] A first aspect of an embodiment of the present application provides a pretreatment device for a packaging film, which is used to pretreatment the packaging film before assembling a photovoltaic module. The pretreatment device includes a first mold, the first mold includes a first flat body and a plurality of first protrusions arranged in an array, the height of the first protrusion is greater than or equal to 0.01 mm and less than or equal to 0.4 mm, the distance between adjacent first protrusions is greater than or equal to 0.01 mm and less than or equal to 5 mm, and the distance between the first protrusion located at the edge of the first mold and the edge of the first mold is greater than or equal to 5 mm.

[0008] Further, the first mold further includes second protruding portions disposed at least on two opposite edges of the surface of the first body, the height of the second protruding portions being greater than the height of the first protruding portions, and the minimum distance between the second protruding portions and the first protruding portions in the transverse direction being greater than or equal to 5 mm and less than or equal to 20 mm.

[0009] Further, the difference between the height of the second protruding portions and the height of the first protruding portions is greater than or equal to 0.01 mm and less than or equal to 0.4 mm.

[0010] Further, the pretreatment device further includes a second mold, the second mold including a flat second body and third protruding portions disposed at least on two opposite edges of the surface of the second body, the height of the third protruding portions being greater than the height of the first protruding portions; after the second mold and the first mold are assembled, the minimum distance between the third protruding portions and the first protruding portions in the transverse direction is greater than or equal to 5 mm and less than or equal to 20 mm.

[0011] Further, the difference between the height of the third protruding portions and the height of the first protruding portions is greater than or equal to 0.01 mm and less than or equal to 0.4 mm.

[0012] Further, at least part of the surface of the second mold is subjected to matte treatment and / or provided with a release agent.

[0013] Further, the ratio of the height of the first protruding portions to the thickness of the battery string in the photovoltaic module is greater than or equal to 0.3 and less than or equal to 1.2.

[0014] Further, the first protruding portions are strip-shaped, and the first protruding portions are one or more combinations of a strip-shaped body surrounded by at least three planes, a strip-shaped body surrounded by at least one curved surface, or a strip-shaped body surrounded by at least one curved surface and at least one plane;

[0015] The orthographic projection of the first protruding portions on the first body is a protruding projection, the length of the protruding projection being greater than or equal to 500 mm and less than or equal to 2600 mm, and the width of the protruding projection being greater than or equal to 120 mm and less than or equal to 250 mm.

[0016] Further, the first protruding portions are one or more combinations of a prism, a frustum of a pyramid, a semi-cylinder, or a bow-shaped column.

[0017] Further, at least part of the surface of the first mold is subjected to matte treatment and / or provided with a release agent.

[0018] In a second aspect of the embodiments of the present application, a pretreatment method for an encapsulation adhesive film is provided, the pretreatment method including:

[0019] Cutting, cutting the encapsulation adhesive film according to the required size;

[0020] Pre-lamination: The cut encapsulation film is preheated and pressed to obtain a pre-treated encapsulation film. The pre-treated encapsulation film includes several cell grooves capable of accommodating solar cells, and the cell grooves are arranged in an array.

[0021] Furthermore, the pre-treatment method is implemented by using the pre-treatment device according to any one of claims 1 to 5.

[0022] Furthermore, during pre-lamination, the melt index of the encapsulation film is controlled to be greater than or equal to 3 g / 10 min and less than or equal to 50 g / 10 min; after pre-lamination, the crosslinking degree of the pre-treated encapsulation film is less than or equal to 10%.

[0023] Furthermore, during pre-lamination, the treatment temperature is controlled to be greater than or equal to 50 °C and less than or equal to 100 °C, the treatment pressure is controlled to be greater than or equal to 1 MPa and less than or equal to 30 MPa, and the treatment time is controlled to be greater than or equal to 5 s and less than or equal to 60 s.

[0024] The third aspect of the present application provides a pre-treated encapsulation film, which is obtained by treating the encapsulation film with the aforementioned pre-treatment device or by treating the encapsulation film with the aforementioned pre-treatment method.

[0025] Therefore, the technical solutions in the present application have the following technical effects:

[0026] 1. The pre-treatment device and pre-treatment method in the present application can pre-treat the encapsulation film before assembling the photovoltaic module, so that the pre-treated encapsulation film has a surface structure matching the battery string or solar cells to be assembled.

[0027] 2. The pre-treatment device and pre-treatment method in the present application have wide applicability, can be applied to all structures of encapsulation films, and can reduce the types and procurement costs of encapsulation films. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the component structure during the encapsulation of a photovoltaic module in the prior art;

[0029] Figure 2 It is a three-dimensional schematic diagram of the structure of a first mold in the pre-treatment device provided by the present application;

[0030] Figure 3 It is a three-dimensional schematic diagram of the structure of another first mold in the pre-treatment device provided by the present application;

[0031] Figure 4 It is a schematic diagram of the component structure of a photovoltaic module encapsulation using the encapsulation film treated by the pre-treatment device provided by the present application;

[0032] Figures 5 to 6Schematic diagrams of two types of first molds in the pretreatment device provided by the present application in sequence;

[0033] Figures 7 to 8 Top view schematic diagrams of two types of first molds in the pretreatment device provided by the present application in sequence (the shaded parts in the figures represent protrusions, the same below);

[0034] Figure 9 Schematic diagram of a second mold in the pretreatment device provided by the present application

[0035] Figure 10 Schematic diagram of the structure of the pretreatment device provided by the present application;

[0036] Figures 11 to 16 Schematic diagrams of six other types of first molds in the pretreatment device provided by the present application in sequence;

[0037] Figure 17 Top view schematic diagram of another first mold in the pretreatment device provided by the present application.

[0038] In the figure: photovoltaic module 100, front substrate 11, encapsulation adhesive film 12, cell string 13, rear substrate 14;

[0039] Pretreatment device 200, first mold 21, first body 211, first protrusion 212, second protrusion 213, second mold 22, second body 221, third protrusion 222. Specific embodiments

[0040] In order to enable those skilled in the art to better understand the solution of the present application, the technical solutions in the specific embodiments of the present application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present application.

[0041] In the first aspect of the embodiments of the present application, a pretreatment device 200 for an encapsulation adhesive film is provided. The pretreatment device 200 is used to pretreat the encapsulation adhesive film before assembling the photovoltaic module, and can form a film groove on the surface of the encapsulation adhesive film that can accommodate the cell and a film protrusion that can fill the gap between the cells. The pretreatment device 200 includes as Figure 2 or Figure 3The first mold 21 shown includes a first body 211 and a first protrusion 212. The first body 211 is substantially flat, and all first protrusions 212 are distributed in an array on the same surface of the first body 211. In the first mold 21, the array arrangement of the first protrusions 212 is substantially the same as the arrangement of the battery strings in the photovoltaic module. After being processed by the first mold 21, the position corresponding to the first protrusion 212 on the packaging film can form a groove capable of accommodating the battery cell, and at the same time, a protrusion capable of filling the gap between the battery cells is formed between adjacent grooves.

[0042] After being processed by the above-mentioned pretreatment device 200 in the embodiment of the present application, the thickness of the packaging film in the area corresponding to the battery cell is relatively thin, and the thickness in the area corresponding to the gap between the battery cells is relatively thick. After such treatment, problems such as hidden cracks and splits of the battery cell caused by the thicker thickness of the film in the area corresponding to the battery cell can be avoided. It can also avoid the problem that the film is unable to completely fill the gap between the battery cells, resulting in gaps after component packaging. The grooves and protrusions formed on the packaging film can also fix the position of the battery cell, avoid the battery cell from slipping during the component packaging process, and improve the quality rate of photovoltaic cell packaging. In addition, the packaging film treated by the pretreatment device 200 in the embodiment of the present application is used to encapsulate photovoltaic components, such as Figure 4 As shown, the overall thickness of the assembly can be made consistent before lamination, the force uniformity of the assembly during lamination can be improved, and the assembly packaging effect can be improved. The encapsulation film processed by the processing device 200 of the present application is particularly suitable for 0BB assemblies, because 0BB assemblies often have additional connection films (skin films, carrier films, etc.) to form an electrical connection between the welding strip and the battery cell, which leads to a greater height difference between the corresponding position of the battery string and the gap between the battery cells, so the risk of hidden cracks in the battery cells in the 0BB assembly is greater. The use of the above-mentioned encapsulation film can significantly reduce the crack rate in the 0BB assembly.

[0043] like Figure 5As shown, the height H1 of the first protrusion 212 is greater than or equal to 0.01 mm and less than or equal to 0.4 mm. During the component encapsulation process, the encapsulation adhesive films after being processed by the pre-treatment mold for the front and rear layers, or the encapsulation adhesive film processed by the pre-crosslinking mold on one side and the conventional encapsulation adhesive film are matched with the battery string. The battery cells can be basically exactly arranged in the space formed by the two adhesive films and then encapsulated. When the height of the first protrusion 212 is within the above range, it can basically meet the thickness specification of the battery string, so that the pre-treatment device 200 in this application can pre-treat to obtain an encapsulation adhesive film that meets the requirements of photovoltaic cell encapsulation on the market. Optionally, the height H1 of the first protrusion 212 can be 0.01 mm, 0.05 mm, 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm. Of course, it can also be other values within the above range, which are not limited herein.

[0044] The distance L1 between adjacent first protrusions 212 is greater than or equal to 0.01 mm and less than or equal to 5 mm. The distance between adjacent first protrusions 212 is basically adapted to the distance between adjacent battery cells. When the distance between adjacent first protrusions 212 is within the above range, it can basically meet the requirements of the distance between battery cells in the photovoltaic module, so that the pre-treatment device 200 in this application can process and obtain an encapsulation adhesive film that meets the requirements of photovoltaic cell encapsulation on the market. Specifically, the distance between adjacent first protrusions 212 is set according to parameters such as the size of the battery cells in the actual photovoltaic module and the photovoltaic module specifications, but this distance should not be greater than the distance between adjacent battery cells. Optionally, the distance L1 between adjacent first protrusions 212 can be 0.01 mm, 0.02 mm, 0.03 mm, 0.04 mm, 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.5 mm, 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm. Of course, it can also be other values within the above range, which are not limited herein.

[0045] The distance L2 between the first protrusion 212 at the edge of the first mold 21 and the edge of the first mold 21 is greater than or equal to 5 mm. After the first mold 21 processes the encapsulation adhesive film, a protrusion structure will also be formed at the corresponding position between the first protrusion at the edge of the encapsulation adhesive film and the first mold 21 (i.e., the outermost first protrusion on the first mold 21) and the edge of the first mold 21. This protrusion structure is located at the edge of the encapsulation adhesive film and can increase the support of the edge area of the encapsulation adhesive film, so that the edge of the component can also remain flat before encapsulation.

[0046] As an alternative implementation, as Figure 6 shown, the first mold 21 further includes a second protrusion 213 disposed at the surface edge of the first body 211. The height of the second protrusion 213 is greater than the height of the first protrusion 212. The second protrusion 213 at the surface edge of the first mold 21 can function to limit the position of the first mold 21. At the same time, the height of the second protrusion 213 is greater than the height of the first protrusion 212. After the first mold 21 is fitted with any processing plane, a processing cavity can be formed, and this processing cavity is the space for preprocessing the encapsulation film. After preprocessing, the encapsulation film deforms and fills the entire processing cavity, and the encapsulation film can become the expected shape with groove and protrusion structures. The second protrusion 213 can control the distance between the first protrusion 212 and the above-mentioned processing plane, so that a certain distance is maintained between the first protrusion 212 and the processing plane, avoiding the bottom of the groove part in the preprocessed encapsulation film from being too thin and ensuring the encapsulation effect of the encapsulation film.

[0047] As an alternative implementation, as Figure 6 shown, the difference between the height of the second protrusion 213 and the height H2 of the first protrusion 212 is greater than or equal to 0.01 mm and less than or equal to 0.4 mm. The difference between the height of the second protrusion 213 and the height of the first protrusion 212 is basically the thickness of the bottom of the groove area of the encapsulation film obtained after preprocessing. When the difference between the heights of the second protrusion 213 and the first protrusion 212 is within the above range, it can ensure that the bottom of the groove area of the encapsulation film obtained after preprocessing has a certain thickness, and at the same time can avoid encroaching on the groove area due to the excessive thickness of the bottom, ensuring that the groove area can carry the battery cell during the component encapsulation process. Optionally, the difference between the height of the second protrusion 213 and the height H2 of the first protrusion 212 can be 0.01 mm, 0.03 mm, 0.05 mm, 0.07 mm, 0.09 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm. Of course, it can also be other values within the above range, which are not limited here.

[0048] As Figure 6 and Figure 7As shown, the minimum distance L3 between the second protrusion 213 and the first protrusion 212 in the transverse direction is greater than or equal to 5 mm and less than or equal to 20 mm. The first protrusion 212 and the second protrusion 213 cooperate with each other, and the pre-treated encapsulation film can form a raised structure located at the edge of the encapsulation film between the first protrusion 212 and the second protrusion 213. The minimum distance between the second protrusion 213 and the first protrusion 212 in the transverse direction is the width of the raised structure in the transverse direction. When the minimum distance between the second protrusion 213 and the first protrusion 212 in the transverse direction is within the above range, the raised structure formed after pretreatment can not only meet the supporting function, but also avoid the problem of waste of adhesive caused by the over-wide raised structure. Optionally, the minimum distance L3 between the second protrusion 213 and the first protrusion 212 in the transverse direction can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm. Of course, it can also be other values within the above range, which are not limited here.

[0049] As an alternative embodiment, as Figure 7 shown, the second protrusion 213 can be provided only on two opposite edges or three edges of the surface of the first body 211, and the absence of the second protrusion 213 on one edge or two edges can provide a discharge space for the adhesive during the pretreatment process to discharge the excess adhesive during the pretreatment process of the encapsulation film. In an ideal situation, it is optimal that the adhesive content of the encapsulation film before and after pretreatment is equal. However, in actual situations, in order to avoid the situation of lack of adhesive in the encapsulation film after pretreatment, an encapsulation film with a slightly larger adhesive content is usually used for pretreatment. The absence of the second protrusion 213 on at least one edge of the surface of the first body 211 can be used to discharge the excess adhesive. As Figure 8 shown, the second protrusion 213 can also be provided on the four peripheral edges of the first body 211, which can better play a supporting role, make the formed accommodation cavity a substantially closed space, and can avoid the situation that the encapsulation film overflows the pretreatment device 200 due to too strong fluidity during the pretreatment process, and avoid the situation of local lack of adhesive or damage in the encapsulation film after pretreatment. At the same time, in order to discharge the excess adhesive, a plurality of glue discharge channels can also be provided through the second protrusion 213 to discharge the excess adhesive during the pretreatment process.

[0050] As an alternative embodiment, the pretreatment device 200 further includes a second mold 22. As described above, the first mold 21 can cooperate with any plane to complete the pretreatment process in the present application. However, in this embodiment, the second mold 22 with a higher degree of fit with the first mold 21 is provided. After the second mold 22 and the first mold 21 cooperate with each other, a cavity for accommodating the encapsulation film during the pretreatment process can be formed, which can improve the efficiency of the pretreatment and the excellent rate of the encapsulation film after pretreatment.

[0051] As Figure 9 shown, the second mold 22 includes a flat second body 221 and a third protrusion 222 provided on the edge of the surface of the second body 221. The height of the third protrusion 222 is greater than the height of the first protrusion 212. On the one hand, the third protrusion 222 can achieve the function of the aforementioned second protrusion 213. The third protrusion 222 controls the distance between the first protrusion 212 and the second body 221 of the second mold 22, so that a certain distance is maintained between the first protrusion 212 and the processing plane, avoiding the bottom of the groove part in the encapsulation film after pretreatment from being too thin and ensuring the encapsulation effect of the encapsulation film. On the other hand, the third protrusion 222 can also increase the degree of fit between the second mold 22 and the first mold 21, and can avoid problems such as misalignment between the second mold 22 and the first mold 21 during pretreatment, improving the excellent rate of the encapsulation film after pretreatment.

[0052] Furthermore, the third protrusion 222 provided on the second body 221 is basically similar to the second protrusion 213 provided on the aforementioned first body 211. The third protrusion 222 can be provided only on two opposite edges or three of the edges of the surface of the second body 221. The absence of the third protrusion 222 on one edge or two edges can provide a discharge space for the glue material during the pretreatment process. The third protrusion 222 can also be provided on the four peripheral edges of the second body 221. In this way, a better supporting effect can be achieved, and the formed cavity becomes a substantially closed space, which can avoid the situation that the encapsulation film overflows the pretreatment device 200 due to too strong fluidity during the pretreatment process, and avoid the situation that the pretreated encapsulation film has local lack of glue or defects. At the same time, in order to discharge the excess glue material, a plurality of glue discharge channels can be provided through the third protrusion to discharge the excess glue material during the pretreatment process.

[0053] As Figure 10As shown, after the second mold 22 is assembled with the first mold 21, the minimum distance L4 in the transverse direction between the third protrusion 222 and the first protrusion 212 is greater than or equal to 5 mm and less than or equal to 20 mm. Similarly, the third protrusion 222 and the first protrusion 212 cooperate with each other, and the pre-treated encapsulation film can also form a raised structure at the edge of the encapsulation film between the third protrusion 222 and the first protrusion 212. The minimum distance in the transverse direction between the third protrusion 222 and the first protrusion 212 is the width of the raised structure in the transverse direction. When the minimum distance in the transverse direction between the third protrusion 222 and the first protrusion 212 is within the above range, the raised structure formed after pre-treatment can not only meet the supporting function, but also avoid the problem of waste of adhesive caused by the over-wide raised structure. Optionally, the minimum distance L4 in the transverse direction between the third protrusion 222 and the first protrusion 212 can be 5 mm, 6 mm, 7 mm, 8 mm, 9 mm, 10 mm, 11 mm, 12 mm, 13 mm, 14 mm, 15 mm, 16 mm, 17 mm, 18 mm, 19 mm, 20 mm. Of course, it can also be other values within the above range, which are not limited here.

[0054] As an alternative embodiment, as Figure 10 shown, the difference H3 between the height of the third protrusion 222 and the height of the first protrusion 212 is greater than or equal to 0.01 mm and less than or equal to 0.4 mm. The function of the third protrusion 222 is similar to that of the aforementioned second protrusion 213. The difference between the height of the third protrusion 222 and the height of the first protrusion 212 is also basically the thickness of the bottom of the groove area of the encapsulation film obtained after pre-treatment. When the difference in height between the third protrusion 222 and the first protrusion 212 is within the above range, it can ensure that the bottom of the groove area of the encapsulation film obtained after pre-treatment has a certain thickness, and at the same time can avoid the encroachment on the groove area caused by the over-thick bottom, ensuring that the groove area can carry the battery chip during the component encapsulation process. Optionally, the difference between the height of the third protrusion 222 and the height H2 of the first protrusion 212 can be 0.01 mm, 0.03 mm, 0.05 mm, 0.07 mm, 0.09 mm, 0.1 mm, 0.2 mm, 0.3 mm, 0.4 mm. Of course, it can also be other values within the above range, which are not limited here.

[0055] As an alternative embodiment, the ratio of the height of the first protrusion 212 to the thickness of the battery string in the photovoltaic module is greater than or equal to 0.3 and less than or equal to 1.2. When using two layers of encapsulation films pretreated by a pretreatment mold in combination, it is preferred that the ratio of the height of the first protrusion 212 to the thickness of the battery string in the photovoltaic module is greater than or equal to 0.3 and less than or equal to 0.6; when using a single-side pretreated encapsulation film and a conventional encapsulation film in combination, it is preferred that the ratio of the height of the first protrusion 212 to the thickness of the battery string in the photovoltaic module is greater than or equal to 0.5 and less than or equal to 1.2. When the ratio of the height of the first protrusion 212 to the thickness of the battery string is within the above range, it can basically meet the thickness specifications of the battery string or battery cells and the connection film (skin film, carrier film), which can not only make the pretreated encapsulation film play a role in fixing the battery string, but also avoid the problem of affecting the arrangement of the battery string due to the excessive depth of the groove in the pretreated encapsulation film.

[0056] As an alternative embodiment, the first protrusion 212 is strip-shaped, and the first protrusion 212 is one or a combination of one or more of a strip-shaped body surrounded by at least three planes, a strip-shaped body surrounded by at least one curved surface, or a strip-shaped body surrounded by at least one curved surface and at least one plane. The first protrusions 212 are strip-shaped, and all the first protrusions 212 are substantially parallel to each other. The shape of the first protrusion 212 can be selected and set according to actual needs. The shape of the first protrusion 212 needs to meet at least the following two requirements. The first requirement is that the first protrusion 212 can form a groove that meets the requirements on the pretreated encapsulation film. The second requirement is that after pretreatment, the first protrusion 212 is easy to separate from the pretreated encapsulation film and will not cause damage to the encapsulation film.

[0057] Specifically, the first protrusion 212 can be a prism (such as any one shown in Figures 5 to 6 ), a frustum of a pyramid (such as shown in Figure 11 ), or a semi-cylinder (such as shown in Figure 12 ), or a combination of one or more of them. The first protrusion 212 can be a prism, such as a cuboid, etc. The first protrusion 212 in the shape of a prism is easy to process and is also easy to form a groove for placing the battery cells on the encapsulation film. The second protrusion 213 can be a frustum of a pyramid, such as a quadrangular frustum with a larger bottom surface and a smaller top surface. The structure with a smaller top surface of the quadrangular frustum can make the first protrusion 212 easier to demold from the pretreated encapsulation film and better ensure the integrity of the pretreated encapsulation film. The first protrusion 212 can be a semi-cylinder or an arched column (i.e., a columnar body with an arched cross-section in any section perpendicular to the extension direction). In comparison, the semi-cylinder with a curved surface has the advantage of being easier to demold and can better ensure the integrity of the pretreated encapsulation film. The first protrusion 212 can also be a combined shape of a prism and a semi-cylinder (such as shown in Figure 13the combined shape of a prism and an arcuate column (as shown in Figure 14 ), the combined shape of a frustum and a semi-cylinder (as shown in Figure 15 ), or the combined shape of a frustum and an arcuate column (as shown in Figure 16 ). The base of the first convex part 212 is a prism or a frustum, and a semi-cylinder or an arcuate column is arranged on the base. Such an arrangement can not only obtain relatively large and regular grooves on the encapsulation film by using the prism and the frustum, but also facilitate demolding by using the semi-cylinder or the arcuate column at the top, ensuring the integrity of the encapsulation film.

[0058] As an alternative embodiment, the orthographic projection of the first convex part 212 on the first body 211 is a convex projection, as shown in Figure 17 . The length L5 of the convex projection is greater than or equal to 500 mm and less than or equal to 2600 mm, and the width W of the convex projection is greater than or equal to 120 mm and less than or equal to 250 mm. Setting the length and width dimensions of the first convex part 212 within the above range can meet the size requirements of the grooves formed on the encapsulation film, and at the same time, it can also avoid the first convex part 212 being too large to encroach on the convex structure between the grooves on the encapsulation film, ensuring the integrity of the convex structure on the encapsulation film and the required support strength. Optionally, the length L5 of the convex projection can be 500 mm, 600 mm, 700 mm, 800 mm, 900 mm, 1000 mm, 1200 mm, 1400 mm, 1600 mm, 1800 mm, 2000 mm, 2200 mm, 2400 mm, 2600 mm, and the width W of the convex projection can be 120 mm, 130 mm, 140 mm, 150 mm, 160 mm, 170 mm, 180 mm, 190 mm, 200 mm, 210 mm, 220 mm, 230 mm, 240 mm, 250 mm. Of course, it can also be other values within the above range, which are not limited here.

[0059] As an alternative embodiment, for ease of demolding, at least part of the surface of the first mold 21 and / or the second mold 22 is subjected to sandblasting treatment and / or provided with a demolding agent. The sandblasting treatment includes polishing the mold surface with sandpaper, emery cloth, grinding paste or inorganic particles such as quartz sand with appropriate particle size. The particle size of the quartz sand is preferably 600-850 microns. The demolding agent includes silicone-based demolding agents such as siloxane compounds, silicone oils, silicone resin methyl branched silicone oils, methyl silicone oils, emulsified methyl silicone oils, hydrogen-containing methyl silicone oils, silicone greases, silicone resins, silicone rubbers, silicone rubber toluene solutions, etc.; wax series demolding agents such as paraffin wax, microcrystalline wax, polyethylene wax, etc.; fatty acid soap demolding agents such as fatty acids or potassium soaps, sodium soaps, ammonium soaps, zinc soaps, etc.; fluorine-containing demolding agents; polyether demolding agents; inorganic powder demolding agents such as talc, mica, clay, white clay, etc. As long as the purpose of facilitating demolding can be achieved, any conventional demolding treatment method can be used, including but not limited to the sandblasting treatment or the setting of a demolding agent mentioned above, and all should be within the protection scope of this application. Preferably, the surface treatment is used to control the friction coefficient of the mold surface within the range of 0.1-0.15 to achieve efficient demolding.

[0060] The second aspect of the embodiments of this application provides a pretreatment method for an encapsulation film. This pretreatment method mainly includes two steps: cutting and pre-laminating. The encapsulation film is sold in a roll form by the film manufacturer. When the component manufacturer encapsulates the components, it is necessary to first cut the encapsulation film according to the size requirements and then encapsulate the components. In the embodiments of this application, the cut encapsulation film is first subjected to preheating and pressing treatment, so that battery grooves arranged in an array and capable of accommodating battery cells are formed on the encapsulation film.

[0061] As an alternative embodiment, this pretreatment method can be implemented by using the aforementioned pretreatment device 200. The pretreatment method provided by the embodiments of this application can be processed by using any device capable of implementing the above pretreatment. However, using the pretreatment device 200 provided by the embodiments of this application can better and more efficiently implement this pretreatment, and at the same time can also ensure that the treated encapsulation film has more appropriate size specifications and a higher excellent rate.

[0062] As an alternative embodiment, in the pre-lamination, the melt index of the encapsulation film is controlled to be greater than or equal to 3 g / 10 min and less than or equal to 50 g / 10 min (at 190 °C, 2.16 kg). The pretreatment of the encapsulation film in the embodiments of the present application is a pre-lamination treatment method. Compared with the lamination treatment during the encapsulation of photovoltaic modules, the pre-lamination treatment has a lower treatment temperature and a shorter treatment time. When the melt index of the encapsulation film in the pre-lamination treatment is controlled within the above range, it can not only avoid the problem that the encapsulation film has too poor fluidity during the pre-lamination treatment due to too low melt index and cannot present well-shaped and complete grooves on the pretreated encapsulation film, but also avoid defects such as lack of glue caused by excessive fluidity of the encapsulation film during the pre-lamination treatment due to too high melt index.

[0063] As an alternative embodiment, after the pre-lamination, the crosslinking degree of the pretreated encapsulation film is less than or equal to 10%. The pretreatment of the encapsulation film in the embodiments of the present application is a pre-lamination treatment method. During the subsequent encapsulation process of the photovoltaic module, the encapsulation film still needs to be subjected to a lamination treatment. When the crosslinking degree of the pretreated encapsulation film after the pre-lamination is within the above range, it can ensure that the encapsulation film can still generate fluidity during the lamination in the photovoltaic module encapsulation process and realize the bonding of each part in the module, and avoid the problem that the encapsulation film cannot achieve the mutual bonding between the various components in the photovoltaic module due to too high crosslinking degree.

[0064] As an alternative embodiment, in the pre-lamination, the treatment temperature is controlled to be greater than or equal to 50 °C and less than or equal to 100 °C, the treatment pressure is controlled to be greater than or equal to 1 MPa and less than or equal to 30 MPa, and the treatment time is controlled to be greater than or equal to 5 s and less than or equal to 60 s.

[0065] During the pre-lamination process, when the treatment temperature, treatment pressure, and treatment time are controlled within the above range, it can not only make the pretreated encapsulation film present the expected shape and structure, but also avoid having an adverse impact on the subsequent photovoltaic module encapsulation process and avoid problems such as poor connection strength between the various components after the photovoltaic module is encapsulated and even possible peeling and falling off.

[0066] The third aspect of the embodiments of the present application also provides a pretreated encapsulation film, which is obtained by treating the encapsulation film with the aforementioned pretreatment device 200 or by treating the encapsulation film with the aforementioned pretreatment method.

[0067] It should be noted that in the above description, only the protruding structure and its shape and size may be described. However, it is well known that after the formation of the protruding structure, a groove structure is also correspondingly formed between adjacent protruding structures or around the protruding structure. Those of ordinary skill in the art can undoubtedly know the shape and size of the adjacent groove structure according to the description and shape and size limitation of the protruding structure.

[0068] Finally, it should be noted that the above are only some preferred embodiments of the present application and are not used to limit the present application. Although the present application 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 perform equivalent replacements for some of the technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A pretreatment device for an encapsulation film, which is used to pretreat the encapsulation film before assembling a photovoltaic module, and is characterized in that, Comprising: A first mold, the first mold includes a first body in the shape of a flat plate and a number of first protrusions arranged in an array, the height of the first protrusion is greater than or equal to 0.01 mm and less than or equal to 0.4 mm, the distance between adjacent first protrusions is greater than or equal to 0.01 mm and less than or equal to 5 mm, and the distance between the first protrusion located at the edge of the first mold and the edge of the first mold is greater than or equal to 5 mm.

2. The pretreatment device according to claim 1, wherein: The first mold further includes second protrusions provided at least on two opposite edges of the surface of the first body, the height of the second protrusion is greater than the height of the first protrusion, and the minimum distance between the second protrusion and the first protrusion in the lateral direction is greater than or equal to 5 mm and less than or equal to 20 mm; preferably, the difference between the height of the second protrusion and the height of the first protrusion is greater than or equal to 0.01 mm and less than or equal to 0.4 mm.

3. The pretreatment device according to claim 1, wherein: The pretreatment device further includes a second mold, the second mold includes a flat second body and third protrusions provided at least on two opposite edges of the surface of the second body, the height of the third protrusion is greater than the height of the first protrusion; after the second mold and the first mold are assembled, the minimum distance between the third protrusion and the first protrusion in the lateral direction is greater than or equal to 5 mm and less than or equal to 20 mm; Preferably, the difference between the height of the third protrusion and the height of the first protrusion is greater than or equal to 0.01 mm and less than or equal to 0.4 mm; Preferably, at least part of the surface of the second mold is subjected to sandblasting treatment and / or provided with a mold release agent.

4. The pretreatment device according to claim 1, wherein: The ratio of the height of the first protrusion to the thickness of the battery string in the photovoltaic module is greater than or equal to 0.3 and less than or equal to 1.

2.

5. The pretreatment device according to claim 1, wherein: The first protrusion is in a strip shape, and the first protrusion is one or a combination of more of a strip formed by surrounding with at least three planes, a strip formed by surrounding with at least one curved surface, or a strip formed by surrounding with at least one curved surface and at least one plane; The orthographic projection of the first protrusion on the first body is a protrusion projection, the length of the protrusion projection is greater than or equal to 500 mm and less than or equal to 2600 mm, and the width of the protrusion projection is greater than or equal to 120 mm and less than or equal to 250 mm; Preferably, the first protrusion is one or a combination of more of a prism, a frustum of a pyramid, a semi-cylinder or a bow-shaped column; Preferably, at least part of the surface of the first mold is subjected to sandblasting treatment and / or provided with a mold release agent.

6. A pretreatment method for an encapsulation film, characterized in that, Comprising: Cutting, cutting the encapsulation adhesive film according to the required size; Pre-laminating, performing pre-heat pressing treatment on the cut encapsulation adhesive film to obtain a pre-treated encapsulation adhesive film, and the pre-treated encapsulation adhesive film includes a number of battery grooves capable of accommodating battery wafers, and the battery grooves are arranged in an array.

7. The pretreatment method according to claim 6, wherein: The pretreatment method is implemented by using the pretreatment device according to any one of claims 1 to 5.

8. The pretreatment method according to claim 6, wherein: In the pre-lamination, the melt index of the encapsulation adhesive film is controlled to be greater than or equal to 3 g / 10 min and less than or equal to 50 g / 10 min; after the pre-lamination, the crosslinking degree of the pretreated encapsulation adhesive film is less than or equal to 10%.

9. The pretreatment method according to claim 6, wherein: In the pre-lamination, the treatment temperature is controlled to be greater than or equal to 50 °C and less than or equal to 100 °C, the treatment pressure is controlled to be greater than or equal to 1 MPa and less than or equal to 30 MPa, and the treatment time is controlled to be greater than or equal to 5 s and less than or equal to 60 s.

10. A pretreated encapsulation adhesive film, wherein: The pretreated encapsulation adhesive film is obtained by treating an encapsulation adhesive film with the pretreatment device according to any one of claims 1 to 5 or by treating an encapsulation adhesive film with the pretreatment method according to any one of claims 6 to 9.

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