Packaging adhesive film and photovoltaic module

Abstract

The utility model discloses a packaging adhesive film and a photovoltaic module, the packaging adhesive film comprises at least one POE film layer and at least two EVA film layers distributed on the edge of the POE film layer, the POE film layer is arranged between the two EVA film layers, and the thickness of the EVA film layer is the same as that of the POE film layer. The photovoltaic module comprises a battery string, a plurality of bus bars connected with the battery string, and the packaging adhesive film, the EVA film layers of the packaging adhesive film cover the upper and lower surfaces of the bus bars, and the POE film layers of the packaging adhesive film cover the upper and lower surfaces of the battery string. The packaging adhesive film provided by the utility model has good anti-PID performance, prevents water vapor from permeating and corroding the cell string, and has good adhesive performance. Bonding between the packaging adhesive film and the battery string is reliable, and layered bubbles caused by insufficient cross-linking degree of the end part are avoided.

Description

Technical Field

[0001] The utility model belongs to the technical field of solar cells, and in particular relates to a packaging adhesive film and a photovoltaic component. Background Art

[0002] As one of the important components of photovoltaic modules, the encapsulation film is located between the battery string and the glass or backplane, playing the role of bonding and encapsulation, blocking water vapor, and protecting the battery cells. The film's transmittance, volume resistivity, weather resistance, and anti-PID performance are crucial to the power generation efficiency and operating life of photovoltaic modules.

[0003] With the promotion and application of battery technologies such as PERC and TOPCon bifacial cells, POE film is widely used to improve the reliability of components. It has the advantages of good anti-PID performance, low water vapor permeability, slow aging and yellowing, and can prevent battery cell corrosion. However, during the manufacturing process of photovoltaic components, due to the poor compatibility of POE film with additives, the additives are easy to precipitate, the POE film itself has poor polarity, and the adhesion with the material is relatively weak, which leads to the phenomenon of edge stratification and bubbles during the aging process; at the same time, the problem of slippage between POE film and battery string is also prone to occur during the manufacturing process.

[0004] The information disclosed in this background technology section is only intended to increase the understanding of the overall background of the present invention, and should not be regarded as acknowledging or suggesting in any form that the information constitutes the prior art already known to a person skilled in the art. Utility Model Content

[0005] The utility model aims to provide a packaging adhesive film and a photovoltaic module, which can have good anti-PID performance, prevent water vapor from penetrating and corroding the battery string, and have good bonding performance.

[0006] In order to achieve the above purpose, the technical solution provided by a specific embodiment of the utility model is as follows:

[0007] A packaging adhesive film comprises: a plurality of EVA film layers distributed at intervals and at least one POE film layer, wherein the POE film layer is arranged between two adjacent EVA film layers, and the EVA film layer and the POE film layer have the same thickness.

[0008] In one or more embodiments of the present invention, the packaging film includes two EVA film layers and one POE film layer, the length of the EVA film layer is 2 mm to 30 mm, and the length of the POE film layer is 800 mm to 3000 mm.

[0009] In one or more embodiments of the present invention, the length of the EVA film layer is 3 mm to 20 mm; and / or,

[0010] The length of the POE film layer is 1000 mm to 2600 mm.

[0011] In one or more embodiments of the present invention, the packaging film includes three EVA film layers and two POE film layers, the length of the EVA film layer is 2 mm to 30 mm, and the length of the POE film layer is 500 mm to 1500 mm.

[0012] In one or more embodiments of the present invention, the length of the EVA film layer is 3 mm to 20 mm; and / or,

[0013] The length of the POE film layer is 600 mm to 1300 mm.

[0014] In one or more embodiments of the present invention, the thickness of the packaging film is 0.2 mm to 1 mm.

[0015] Another specific embodiment of the present invention provides a technical solution as follows:

[0016] A photovoltaic module, characterized in that the photovoltaic module includes a battery string, a plurality of bus bars connected to the battery string, and the aforementioned packaging film, wherein the EVA film layer in the packaging film covers the upper surface and / or lower surface of the bus bar, and the POE film layer in the packaging film covers the upper surface and / or lower surface of the battery string.

[0017] In one or more embodiments of the present invention, the photovoltaic module includes two or three bus bars, and adjacent bus bars include sub-battery strings composed of multiple battery cells. The length of the EVA film layer is greater than or equal to the width of the bus bar, and the length of the POE film layer is greater than or equal to the length of the sub-battery string and less than or equal to the spacing distance between two adjacent bus bars.

[0018] In one or more embodiments of the present invention, the battery cell is a P-type battery cell, the EVA film layer in the packaging film covers the lower surface of the bus bar, the POE film layer in the packaging film covers the lower surface of the battery string, and the lower surface of the packaging film is provided with a backplane.

[0019] In one or more embodiments of the present invention, the battery cell is an N-type battery cell, the EVA film layer in the packaging film covers the upper surface of the bus bar, the POE film layer in the packaging film covers the upper surface of the battery string, and a glass plate is provided on the upper surface of the packaging film.

[0020] Compared with the prior art, the utility model has the following beneficial effects:

[0021] The utility model provides a packaging film, which has the advantages of good PID resistance of the POE film layer, ability to avoid water vapor intrusion, slow aging and yellowing, and protection of battery strings from corrosion, and has the excellent bonding performance of the EVA film layer;

[0022] The utility model provides a photovoltaic component, which has the advantages of good packaging effect, being able to avoid the occurrence of delamination bubbles at the end, improving the cross-linking degree, having strong bonding ability, and improving the anti-PID performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0024] Figure 1 This is a schematic cross-sectional structural diagram of the packaging film in the first embodiment of the utility model;

[0025] Figure 2 This is a schematic cross-sectional view of the packaging film in the second embodiment of the present utility model;

[0026] Figure 3 This is a schematic diagram of the main structure of the battery string in the third embodiment of the present utility model;

[0027] Figure 4 This is a schematic diagram of the main structure of the photovoltaic assembly in the third embodiment of the present utility model;

[0028] Figure 5 for Figure 4 A magnified view of the local structure at point A in the middle;

[0029] Figure 6 This is a schematic diagram of the three-dimensional structure of the photovoltaic module in the third embodiment of the present utility model;

[0030] Figure 7 This is a schematic diagram of the three-dimensional structure of the photovoltaic module in the fourth embodiment of the present utility model;

[0031] Figure 8 This is a schematic diagram of the main structure of a battery string in Embodiment 5 of the present utility model;

[0032] Fig. 9 This is a schematic diagram of the main structure of the photovoltaic assembly in the fifth embodiment of the present utility model.

[0033] Fig.10 This is an exploded view of the photovoltaic module in the third embodiment of the present utility model. DETAILED DESCRIPTION

[0034] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0035] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0036] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0037] The technical solution of the present utility model will be described below in conjunction with the accompanying drawings.

[0038] The utility model discloses a packaging film, which includes: a plurality of EVA film layers distributed at intervals and at least one POE film layer, the POE film layer is arranged between two adjacent EVA film layers, and the thickness of the EVA film layer and the POE film layer are the same. According to this design, compared with the traditional packaging film in which the entire film layer is composed of POE material, the packaging film in this embodiment has the advantages of good PID resistance of the POE film layer, the ability to avoid water vapor intrusion, slow aging and yellowing, and protection of the battery string 3 from corrosion, and the excellent bonding performance of the EVA film layer.

[0039] Specifically, the thickness of the packaging film in the present invention is 0.2 mm to 1 mm. Exemplarily, the thickness of the packaging film is 0.2 mm, or 1 mm, or any thickness value between 0.2 mm and 1 mm.

[0040] Embodiment 1:

[0041] Reference Figure 1 As shown, this embodiment discloses a packaging film, which includes two EVA film layers 1 and one POE film layer 2, the length L1 of the EVA film layer 1 is 2mm to 30mm, and the length L2 of the POE film layer 2 is 800mm to 3000mm. Among them, the length L1 of the EVA film layer 1 is 2mm, or 30mm, or any length value of 2mm to 30mm. The length L2 of the POE film layer 2 is 800mm, or 3000mm, or any length value of 800mm to 3000mm.

[0042] Preferably, the length L1 of the EVA film layer 1 in this embodiment is 3 mm to 20 mm; the length L2 of the POE film layer 2 is 1000 mm to 2600 mm. The length L1 of the EVA film layer 1 is 3 mm, or 20 mm, or any length value of 3 mm to 20 mm, and the length L2 of the POE film layer 2 is 1000 mm, or 2600 mm, or any length value of 1000 mm to 2600 mm.

[0043] Preferably, the EVA film layer 1 is distributed at the edge of the POE film layer 2 and is integrally connected to the edge of the POE film layer 2, and preferably the connection is achieved by a co-extrusion process.

[0044] Embodiment 2:

[0045] Reference Figure 2 As shown, this embodiment discloses a packaging film, which includes three EVA film layers 1 and two POE film layers 2, the length L1 of the EVA film layer 1 is 2mm to 30mm, and the length L2 of the POE film layer 2 is 500mm to 1500mm. Among them, the length L1 of the EVA film layer 1 is 2mm, or 30mm, or any length value of 2mm to 30mm. The length L2 of the POE film layer 2 is 500mm, or 1500mm, or any length value of 500mm to 1500mm. Preferably, the length L1 of the EVA film layer 1 in this embodiment is 3mm to 20mm, and the length L2 of the POE film layer 2 is 600mm to 1300mm. Among them, the length L1 of the EVA film layer 1 is 3mm, or 20mm, or any length value of 3mm to 20mm, and the length L2 of the POE film layer 2 is 500mm, or 1500mm, or any length value of 500mm to 1500mm.

[0046] Embodiment three:

[0047] Reference Figure 3 to Figure 5 and Fig.10As shown, the present embodiment discloses a photovoltaic module, which includes a battery string 3, a glass plate 42 and a back plate 43 arranged on the upper and lower sides of the battery string 3, and the battery string 3 and the glass plate 42 and / or the battery string 3 and the back plate 43 are encapsulated by an encapsulation film such as in any one of the first embodiment or the second embodiment. Among them, the battery string 3 includes a plurality of sub-battery strings 30 arranged between two adjacent bus bars 31. The sub-battery string 30 includes a plurality of battery cells 32. Exemplarily, a plurality of bus bars 31 (top bus bar 31, central bus bar 31 and bottom bus bar 31) are connected to the top, bottom and center of the battery string 3, so there are two sub-battery strings 30. The EVA film layer 1 is encapsulated between the bus bar 31 and the glass plate 42 and / or between the bus bar 31 and the back plate 43, and the POE film layer 2 is encapsulated between the battery string 3 and the glass plate 42 and / or between the battery string 3 and the back plate 43. As Fig.10 As shown, when the upper and lower sides of the battery string 3 are provided with a glass plate 42 and a back plate 43 respectively, in the vertical direction, the POE film layer 2 is arranged correspondingly to the upper and lower distribution areas of the battery string 3, and the EVA film layer 1 is arranged correspondingly to the upper and lower distribution areas of the bus bar 31, that is, the EVA film layer 1 covers the upper and lower surfaces of the bus bar 31, and the POE film layer 2 covers the upper and lower surfaces of the two sub-battery strings 30. Because the encapsulation film not only has good anti-PID performance, it can prevent water vapor from penetrating and corroding the battery string 3, and has excellent bonding properties of the EVA film layer. Moreover, due to the fast cross-linking reaction of the EVA film layer, it can avoid insufficient cross-linking at the upper and lower ends of the battery string 3 during the lamination process; at the same time, due to the good bonding effect of the EVA film layer 1, the phenomenon of stratified bubbles on the edge of the battery string 3 after aging of the encapsulation film is avoided; and because the EVA film 1 has good fluidity, it can well fill the height difference and eliminate bubbles. According to this design, the packaging effect between the battery string 3 and the glass plate 42 or the battery string 3 and the back plate 43 in this embodiment is good, which can avoid the appearance of stratified bubbles at the end of the photovoltaic module, improve the cross-linking degree, have strong bonding ability, and improve the anti-PID performance.

[0048] Specifically, in order to completely cover the busbar 31 with the EVA film layer 1 and completely cover the battery string 3 with the POE film layer 2, refer to Figure 4 , Figure 5 As shown, the length and width of the EVA film layer 1 in this embodiment are greater than or equal to the length and width of the bus bar 31, the length and width of the POE film layer 2 are greater than or equal to the length and width of the sub-cell string 30, and the length of the POE film layer 2 is less than the spacing distance between two adjacent bus bars 31. In this way, the bus bar 31 and the cell string 3 can be completely covered by the EVA film layer 1 and the POE film layer 2.

[0049] Reference Figure 4 , Figure 5 As shown, in this embodiment, there are three busbars 31, the battery string 3 includes two sub-battery strings 30, a sub-battery string 30 is provided between two adjacent busbars 31, and the sub-battery string 30 includes a plurality of battery cells 32. The battery string 3 and the glass plate 42 of the photovoltaic module and / or the battery string 3 and the back plate 43 are encapsulated by the encapsulation film as shown in the first embodiment. Since the encapsulation film includes three EVA film layers 1 and two POE film layers 2, the three EVA film layers 1 arranged at intervals can completely encapsulate the three busbars 31, and the POE film layer 2 between each two adjacent EVA film layers 1 can completely encapsulate the sub-battery string 30 between each two adjacent busbars 31.

[0050] Exemplarily, the battery cell in this embodiment is a P-type battery cell or an N-type battery cell. Figure 6 As shown, when the cell in the photovoltaic module is a P-type cell 301, since the anti-PID performance of the lower surface of the P-type cell 301 is poor, the encapsulation film 102 covers the lower surface of the cell string 3, and the lower surface of the encapsulation film 102 is provided with a back plate 43. Of course, the present application is not limited to this, and the photovoltaic module further includes another encapsulation film 101 as in any one of the first embodiment or the second embodiment, and the encapsulation film 101 covers the upper surface of the cell string 3, and the upper surface of the encapsulation film 101 is provided with a glass plate 42.

[0051] Embodiment 4:

[0052] The difference from the third embodiment is that: Figure 7 As shown, when the cell in the photovoltaic module in this embodiment is an N-type cell 302, since the upper surface of the N-type cell 302 has poor anti-PID performance, the encapsulation film 101 covers the upper surface of the cell string 3, and the upper surface of the encapsulation film 101 is provided with a glass plate 42. Of course, the present application is not limited to this, and the photovoltaic module further includes another encapsulation film 102 as in any one of the first embodiment or the second embodiment, and the encapsulation film 102 covers the lower surface of the cell string 3, and the lower surface of the encapsulation film 102 is provided with a back plate 43.

[0053] Embodiment five:

[0054] The difference from the third or fourth embodiment is that: Figure 8 , Fig. 9As shown, in this embodiment, there are two busbars 31, the battery string 3 includes a sub-battery string 30, the sub-battery string 30 is arranged between adjacent busbars 31, and the sub-battery string 30 includes a plurality of battery cells 32. The battery string 3 and / or the glass plate 42 of the photovoltaic module or the battery string 3 and the back plate 43 are encapsulated by an encapsulation film as in any one of the first embodiment or the second embodiment. Since the encapsulation film includes two EVA film layers and one POE film layer, the EVA film layers at both ends can completely encapsulate the busbars 31 at both ends, and the middle POE film layer can encapsulate the middle sub-battery string 30.

[0055] It can be seen from the above technical solutions that the utility model has the following beneficial effects:

[0056] The utility model provides a packaging film, which has the advantages of good PID resistance of the POE film layer, ability to avoid water vapor intrusion, slow aging and yellowing, and protection of battery strings from corrosion, and has the excellent bonding performance of the EVA film layer;

[0057] The utility model provides a photovoltaic component, which has the advantages of good packaging effect, being able to avoid the occurrence of delamination bubbles at the end, improving the cross-linking degree, having strong bonding ability, and improving the anti-PID performance.

[0058] In the description of the embodiments of the present invention, it should be understood that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, or are the orientations or positional relationships in which the product of the application is conventionally placed when in use, or are the orientations or positional relationships conventionally understood by those skilled in the art. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0059] In the description of the embodiments of the present utility model, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "set", "install", "connect", and "connect" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be directly connected, or indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0060] In the description of the embodiments of the present invention, it is also necessary to explain that the "first", "second", etc. used in this article do not specifically refer to the order or sequence, nor are they used to limit the present case. They are only used to distinguish components or operations described with the same technical terms.

[0061] It is obvious to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential features of the present invention. Therefore, the embodiments should be regarded as exemplary and non-restrictive from any point of view, and the scope of the present invention is defined by the appended claims rather than the above description, and it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims be included in the present invention. Any reference numeral in a claim should not be regarded as limiting the claim to which it relates.

[0062] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A packaging film, characterized in that: The packaging film comprises: at least one POE film layer and at least two EVA film layers distributed on the edges of the POE film layer, the POE film layer is arranged between the two EVA film layers, and the EVA film layer and the POE film layer have the same thickness.

2. The packaging film according to claim 1, characterized in that: The packaging film comprises two EVA film layers and one POE film layer, the length of the EVA film layer is 2 mm to 30 mm, and the length of the POE film layer is 800 mm to 3000 mm.

3. The packaging film according to claim 2, characterized in that: The length of the EVA film layer is 3 mm to 20 mm; and / or, The length of the POE film layer is 1000 mm to 2600 mm.

4. The packaging film according to claim 1, characterized in that: The packaging film includes three EVA film layers and two POE film layers, the length of the EVA film layer is 2 mm to 30 mm, and the length of the POE film layer is 500 mm to 1500 mm.

5. The packaging film according to claim 4, characterized in that: The length of the EVA film layer is 3 mm to 20 mm; and / or, The length of the POE film layer is 600 mm to 1300 mm.

6. The packaging film according to claim 1, characterized in that: The packaging film has a thickness of 0.2 mm to 1 mm.

7. A photovoltaic module, characterized in that: The photovoltaic module includes a battery string, a plurality of bus bars connected to the battery string, and an encapsulation film as described in any one of claims 1 to 6, wherein the EVA film layer in the encapsulation film covers the upper surface and / or lower surface of the bus bar, and the POE film layer in the encapsulation film covers the upper surface and / or lower surface of the battery string.

8. The photovoltaic module according to claim 7, characterized in that: The photovoltaic module includes two or three bus bars, and adjacent bus bars include sub-battery strings composed of multiple battery cells. The length of the EVA film layer is greater than or equal to the width of the bus bar, and the length of the POE film layer is greater than or equal to the length of the sub-battery string and less than or equal to the spacing distance between two adjacent bus bars.

9. The photovoltaic module according to claim 8, characterized in that: The battery cell is a P-type battery cell, the EVA film layer in the packaging film covers the lower surface of the bus bar, the POE film layer in the packaging film covers the lower surface of the battery string, and the lower surface of the packaging film is provided with a backplane.

10. The photovoltaic module according to claim 8, characterized in that: The battery cell is an N-type battery cell, the EVA film layer in the packaging film covers the upper surface of the bus bar, the POE film layer in the packaging film covers the upper surface of the battery string, and a glass plate is provided on the upper surface of the packaging film.

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