Transverse distribution co-extrusion adhesive film

Abstract

The invention relates to a photovoltaic packaging adhesive film, and provides a transverse distribution co-extrusion adhesive film which comprises a first water blocking area, a first water absorption area firmly combined with one side edge of the first area, a central area firmly combined with one side edge of the first water absorption area, and a second water absorption area firmly combined with one side edge of the central area. The second water blocking area is firmly bonded with the side edge of the second water absorption area; thus, through the arrangement of the first water absorption area and the second water absorption area, water vapor penetrating through the first water blocking area and the second water blocking area can be completely captured by the first water absorption area and the second water absorption area, and then the water vapor located on one side of the photovoltaic packaging adhesive film is protected. And the battery protected by the packaging adhesive film cannot be eroded and damaged by water vapor.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of photovoltaic modules, in particular to a transverse distribution co-extrusion adhesive film. BACKGROUND

[0002] Photovoltaic cell groups generally need to be encapsulated with adhesive films to protect the crystalline silicon cell pieces, solder strips and busbars from the effects of the weather, especially the effects of moisture on the battery; because once moisture enters the surface of the battery, it is very easy to form an electrolyte and corrode the surface of the battery, ultimately severely reducing the power generation efficiency of the battery.

[0003] In order to prevent the above negative effects, the industry uses various adhesive films to achieve water blocking effectiveness, among which the effective one is to use POE material to seal the edge. This is to use POE material on the edge of the whole adhesive film to achieve the effect of water blocking; therefore, the transverse distribution co-extrusion adhesive film has emerged. The main components of this adhesive film are POE + EVA + POE. Patent CN111584661A discloses such a transverse co-extrusion adhesive film; including a middle film layer, and side edge film layers co-extruded on opposite sides of the middle film layer. The side edge film layers are located on both sides of the middle film layer, and the middle film layer and the side edge film layers are in the same plane. The middle film layer is usually an EVA layer or an EVA and POE interlayer, and the frame film layer is a POE layer. The patent uses the advantages of high water resistance and non-hydrolysis of POE to effectively prevent water vapor from penetrating into the module from the edge of the glass, avoid the corrosion of water vapor on the battery component, and improve the water vapor resistance of the module. However, with the passage of time, and the occurrence of adhesive film aging and yellowing, the water blocking function of POE gradually declines, so that water vapor still cannot be avoided to slowly penetrate into the surface of the battery between the side edge film layer (POE) and the glass due to capillary phenomenon, resulting in a decrease in the light / electricity conversion efficiency of the battery. Therefore, the water blocking function of the side edge film layer (POE) is well known, and its effectiveness cannot be denied, but unfortunately its unparalleled effectiveness has been damaged over time.

[0004] Therefore, it is necessary to develop a new type of transverse distribution co-extrusion adhesive film, which can mainly prevent water vapor from entering the photovoltaic module, thereby prolonging the service life of the photovoltaic module. SUMMARY

[0005] The purpose of the present application is to overcome the shortcomings in the prior art, and to provide a transverse distribution co-extrusion adhesive film which has excellent water vapor blocking effect on the photovoltaic module, thereby prolonging the service life of the photovoltaic module.

[0006] The main objective of this invention is to provide a transversely distributed co-extruded film, the technical solution of which is as follows: The transversely distributed co-extruded film includes: First water-blocking zone; The first water-absorbing zone is firmly bonded to one side of the first water-blocking zone; A central zone is firmly bonded to one side of the first absorbent zone; A second absorbent zone is firmly bonded to one side of the central zone, and The second water-blocking zone is firmly bonded to the side of the second water-absorbing zone. Thus, through the water-blocking function of the first and second water-blocking zones, as well as the water-absorbing function of the first and second water-absorbing zones, protection against water vapor erosion can be provided.

[0007] Another object of the present invention is that the first water-absorbing region and the second water-absorbing region include a nanoporous structure.

[0008] Another object of the present invention is that the first absorbent zone and the second absorbent zone include one or more of sodium polyacrylate, cellulose, starch-acrylate graft copolymer, polyacrylamide polymer, diatomaceous earth, montmorillonite, and zeolite.

[0009] Another object of the present invention is that the nanoporous structure is zeolite.

[0010] Another object of the present invention is that the first water-blocking region and the second water-blocking region are POE.

[0011] Another object of the present invention is that the first water-absorbing region and the second water-absorbing region include the material of the first water-blocking region.

[0012] Another object of the present invention is that the first absorbent region and the second absorbent region include the material of the central region.

[0013] Another object of the present invention is that the first absorbent region and the second absorbent region include the material of the central region and the material of the first water-blocking region.

[0014] Another object of the present invention is that the area of ​​the first water-blocking region is smaller than the area of ​​the first water-absorbing region, and at the same time, the area of ​​the second water-blocking region is smaller than the area of ​​the second water-absorbing region.

[0015] Compared with existing technologies, the transversely distributed co-extruded film provided by this invention has the following beneficial effects: In addition to preventing water vapor from entering by setting a first water-blocking zone and a second water-blocking zone, a first water-absorbing zone and a second water-absorbing zone are also provided to enhance the water-blocking effect. Thus, when the first and second water-blocking zones lose their strong water-blocking effect due to aging, the first and second water-absorbing zones will directly absorb the infiltrated water vapor, preventing it from remaining on the battery surface and causing corrosion of the photovoltaic module's cells due to water vapor infiltration. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0017] Figure 1 A side view of the transversely distributed co-extruded film provided by the present invention.

[0018] The diagram shows the following labels: 1-First water-blocking zone; 2-First water-absorbing zone; 3-Central zone; 4-Second water-absorbing zone; 5-First water-blocking zone. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Example

[0020] See Figure 1 This embodiment provides a transversely distributed co-extruded film, along a predetermined direction, as if in... Figure 1 In the first direction shown, a first water-blocking area 1, a first water-absorbing area 2 firmly bonded to the side of the first water-blocking area 1, a central area 3 firmly bonded to the side of the first water-absorbing area 2, a second water-absorbing area 4 firmly bonded to the side of the central area 3, and a second water-blocking area 5 firmly bonded to the side of the second water-absorbing area 4 are distributed sequentially.

[0021] To achieve the water-blocking effect of the first water-blocking zone 1 and the second water-blocking zone 5, the material used for the first water-blocking zone 1 and the second water-blocking zone 5 is polyolefin elastomer (POE). Conversely, the first water-absorbing zone 2 and the second water-absorbing zone 4 are designed to prevent moisture from slowly seeping into the gaps between the first water-blocking zone 1, the second water-blocking zone 5, and the battery (not shown) located below them after prolonged use, thus preventing damage to the battery's performance. To achieve this, the first water-absorbing zone 2 and the second water-absorbing zone 4 contain a nanoporous structure, such as zeolite; the pores of the nanoporous structure adsorb moisture, preventing moisture from corroding the components protected by the encapsulation film. In addition to the nanoporous structure, the first water-absorbing zone 2 and the second water-absorbing zone 4 may also selectively contain one or more of sodium polyacrylate, cellulose, starch-acrylate graft copolymer, polyacrylamide polymer, diatomaceous earth, and montmorillonite.

[0022] It is worth noting that the novel encapsulating film proposed in this application contains the same material in both the first water-absorbing region 2 and the second water-absorbing region 4 as in the first water-blocking region 1 and the second water-blocking region 5; thus, the first water-absorbing region 2 and the second water-absorbing region 4 simultaneously possess the functions of water absorption and water blocking. Furthermore, the material of the central region 3 is ethylene / vinyl acetate (EVA). Similarly, the first water-absorbing region 2 and the second water-absorbing region 4 include the material of the central region 3. Moreover, in order to fully achieve the purpose of water absorption, the areas of the first water-absorbing region 2 and the second water-absorbing region 4 are respectively larger than the areas of the first water-blocking region 1 and the second water-blocking region 5.

[0023] Furthermore, by setting the widths of the first and third regions, as well as the proportions of the widths of the first and second water-absorbing regions within the total width of the adhesive film, the water-blocking performance of the first and third regions, and the adhesion performance of the first and second water-absorbing regions, can be maximized. The POE mass fraction in the first and second water-absorbing regions decreases towards the second region, thus minimizing the amount of POE used, reducing the cost of the adhesive film, and meeting market demands. In particular, the proportion of the widths of the first and second permeation regions is significantly larger than the interface width between the edge film layer and the intermediate film layer in existing technologies. This results in a more robust and stable connection between the first water-blocking region and the adhesion region via the first permeation region, and a more robust and stable connection between the second water-blocking region and the adhesion region via the second permeation region, significantly enhancing aging resistance.

[0024] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A transversely distributed co-extruded film, characterized in that: Includes: First water-blocking zone; The first water-absorbing zone is firmly bonded to one side of the first water-blocking zone; A central zone is firmly bonded to one side of the first absorbent zone; A second absorbent zone is firmly bonded to one side of the central zone, and The second water-blocking zone is firmly bonded to the side of the second water-absorbing zone. Thus, through the water-blocking function of the first and second water-blocking zones, as well as the water-absorbing function of the first and second water-absorbing zones, protection against water vapor erosion can be provided.

2. The transversely distributed co-extruded film according to claim 1, characterized in that: The first and second water-absorbing regions include nanoporous structures.

3. The transversely distributed co-extruded film according to claim 1, characterized in that: The first and second absorbent zones include one or more of sodium polyacrylate, cellulose, starch-acrylate graft copolymer, polyacrylamide polymer, diatomaceous earth, montmorillonite, and zeolite.

4. The transversely distributed co-extruded film according to claim 2, characterized in that: The nanoporous structure is zeolite.

5. The transversely distributed co-extruded film according to claim 3, characterized in that: The first water-blocking zone and the second water-blocking zone are POE.

6. The transversely distributed co-extruded film according to claim 1 or 3, characterized in that: The first water-absorbing zone and the second water-absorbing zone include the material of the first water-blocking zone.

7. The transversely distributed co-extruded film according to claim 1 or 3, characterized in that: The first absorbent zone and the second absorbent zone include the material of the central zone.

8. The transversely distributed co-extruded film according to claim 6, characterized in that: The first absorbent zone and the second absorbent zone include the material of the central zone and the material of the first water-blocking zone.

9. The transversely distributed co-extruded film according to claim 7, characterized in that: The first absorbent zone and the second absorbent zone include the material of the central zone and the material of the first water-blocking zone.

10. The transversely distributed co-extruded film according to claim 1 or 3, characterized in that: The area of ​​the first water-blocking zone is smaller than the area of ​​the first water-absorbing zone, and the area of ​​the second water-blocking zone is smaller than the area of ​​the second water-absorbing zone.

11. The transversely distributed co-extruded film according to claim 8, characterized in that: The area of ​​the first water-blocking zone is smaller than the area of ​​the first water-absorbing zone, and the area of ​​the second water-blocking zone is smaller than the area of ​​the second water-absorbing zone.

12. The transversely distributed co-extruded film according to claim 9, characterized in that: The area of ​​the first water-blocking zone is smaller than the area of ​​the first water-absorbing zone, and the area of ​​the second water-blocking zone is smaller than the area of ​​the second water-absorbing zone.

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