CN217719624U - Photovoltaic module - Google Patents

Abstract

The embodiment of the application relates to the technical field of photovoltaic power generation, and discloses a photovoltaic module which comprises a battery string, a packaging adhesive film and a cover plate, wherein the battery string comprises a plurality of battery pieces which are sequentially connected in series; the packaging adhesive film covers the surface of the battery string, the packaging adhesive film comprises a middle part with preset thickness and edge parts distributed on two sides of the middle part along a first direction, the thickness of the two edge parts is larger than that of the middle part, the thickness of each edge part is gradually increased along the direction far away from the middle part, the ratio of the preset thickness to the thickness of the battery piece is 1-4, and the first direction is perpendicular to the thickness direction of the middle part; the cover plate covers the surface of the packaging adhesive film, which is far away from the battery string. The photovoltaic module that this application embodiment provided can improve the bad phenomenon that photovoltaic module local position appears when reducing the grammes per square metre of encapsulation glued membrane.

Description

Photovoltaic module

Technical Field

The embodiment of the application relates to the technical field of photovoltaic power generation, in particular to a photovoltaic module.

Background

With the continuous development of solar cells, the cost reduction of photovoltaic modules is more and more important. The packaging adhesive film is used as a component playing a role of packaging the battery string in the photovoltaic module, and the reliability of the solar battery can be improved to a certain extent. In the packaging process of the photovoltaic module, the packaging adhesive film is crosslinked after being melted and can be filled between the cover plate and the battery string to play a role in bonding. The filling degree of the packaging adhesive film influences the performance of the photovoltaic module, and in some cases, the problem that the local adhesive amount of the photovoltaic module is not enough can be avoided due to the fact that the adopted packaging adhesive film has a large gram weight.

However, in order to reduce the cost, after the gram weight of the encapsulant film is reduced, the local position of the photovoltaic module is blackened during an EL (electroluminescence) test, and even fragments, cracks, and the like may occur. Therefore, how to reduce the gram weight of the packaging adhesive film and improve the bad phenomenon occurring at the local position of the photovoltaic module is an important problem.

SUMMERY OF THE UTILITY MODEL

An object of the embodiment of the application is to provide a photovoltaic cell, can reduce the grammes per square metre of encapsulation glued membrane, improve the bad phenomenon that photovoltaic module local position appears.

In order to solve the above technical problem, an embodiment of the present application provides a photovoltaic module, which includes a battery string, a packaging adhesive film, and a cover plate, where the battery string includes a plurality of battery pieces connected in series in sequence; the packaging adhesive film covers the surface of the battery string, the packaging adhesive film comprises a middle part with preset thickness and edge parts distributed on two sides of the middle part along a first direction, the thickness of the two edge parts is larger than that of the middle part, the thickness of each edge part is gradually increased along the direction far away from the middle part, the ratio of the preset thickness to the thickness of the battery piece is 1-4, and the first direction is perpendicular to the thickness direction of the middle part; the cover plate covers the surface of the packaging adhesive film, which is far away from the battery string.

The photovoltaic module that this application embodiment provided, under the condition that the middle part of encapsulation glued membrane adopted lower thickness scope, thicken the marginal part of encapsulation glued membrane, make the thickness of two marginal parts of encapsulation glued membrane be greater than the thickness of middle part, increase the local gram weight of encapsulation glued membrane marginal part promptly. Therefore, in the packaging process of the photovoltaic module, the bad phenomenon that the edge of the photovoltaic module is insufficient due to the insufficient glue amount is avoided. Moreover, the thickness of each edge part of the packaging adhesive film is gradually increased along the direction far away from the middle part, so that the edge parts of the packaging adhesive film can be uniformly filled between the battery piece and the cover plate when being melted and crosslinked and overflowing along the direction far away from the middle part. Through thickening to encapsulation glued membrane edge, can improve the bad phenomenon that photovoltaic module local position appears when reducing the grammes per square metre of encapsulation glued membrane.

In some embodiments, a plurality of battery pieces are arranged at intervals along the first direction, or a plurality of battery pieces are arranged in sequence along the first direction, and two adjacent battery pieces are partially overlapped, wherein the thickness of each battery piece is 110 micrometers to 160 micrometers. Therefore, by adopting the cell with the proper thickness, the cost of the photovoltaic module can be reduced, and meanwhile, the photovoltaic conversion efficiency of the photovoltaic module can not be influenced by the cell due to the fact that the thickness of the cell is too small.

In some embodiments, the ratio of the predetermined thickness to the thickness of the battery piece is 1.9 to 2.7; and/or a predetermined thickness of 210 to 420 microns, the maximum thickness of each edge portion not exceeding 600 microns. Therefore, the preset thickness is 1.9-2.7 times of the thickness of the battery piece, the whole gram weight of the packaging adhesive film can be adapted to the thickness of the battery piece, and the packaging adhesive film has proper adhesive amount for bonding for thicker battery pieces, so that the reliability of the battery piece is favorably ensured; the preset thickness of the middle part of the packaging adhesive film is 210-420 micrometers, so that the maximum thickness of each edge part is not more than 600 micrometers, the thickness of each edge part can be kept in a certain range, and the cost of the packaging adhesive film is saved.

In some embodiments, one side edges of the two battery pieces located at the outermost sides in the first direction, which are far away from each other, are covered inside two edge portions, respectively, and the width of each edge portion in the first direction is 40 mm to 80 mm. In this way, it is avoided that the width of each edge portion in the first direction is too small to accommodate the filling at the edges of the photovoltaic module. Meanwhile, the phenomenon that the glue amount is excessive due to the fact that the width of each edge part in the first direction is too large can be avoided.

In some embodiments, each edge portion comprises a plane and an arc-shaped surface which are oppositely arranged along the thickness direction, the plane is connected with one surface of the middle portion far away from the battery piece, and one end, close to the plane, of the arc-shaped surface is connected with one surface, close to the battery piece, of the middle portion. In this way, the thickness of each edge part can be made to show a gradually increasing trend in the direction away from the middle part, so that the edge parts can be more uniformly filled between the battery piece and the cover plate when the edge parts are melted and cross-linked to overflow in the direction away from the middle part.

In some embodiments, a plurality of protruding portions are arranged on one side of the middle portion close to the cell piece, each protruding portion protrudes from the middle portion along the thickness direction of the middle portion, and the arrangement shape of the plurality of protruding portions on the one side of the middle portion close to the cell piece is a discrete strip shape, a grid shape or an array shape. In this way, the adhesion at the cell gaps or the cell stacks can be better adapted by the thickening at the bulges.

In some embodiments, each protruding portion corresponds to a gap between two battery pieces or is overlapped, and the height of each protruding portion in the thickness direction of the middle portion is 10% -40% of the preset thickness. Therefore, the situation that the packaging adhesive film cannot play a good filling effect in the packaging process due to the fact that the height of the protruding portion is too low can be avoided, and waste due to the fact that the height of the protruding portion is too high and the thickness difference of the packaging adhesive film is too large is also avoided.

In some embodiments, the arrangement shape of one surface of the middle part close to the cell piece is a discrete strip shape, the plurality of convex parts are distributed on the middle part at intervals along the second direction, and the width of each convex part in the second direction is 160-230 mm. Thus, by having each projection occupy a width on the intermediate portion, the intermediate portion can be made to provide the required amount of glue during the encapsulation process.

In some embodiments, the second direction is parallel to the first direction, and a cross-sectional shape of each of the projections in the second direction is rectangular. In this way, by setting the sectional shape of each of the projections in the second direction to a regular shape, the production of the encapsulating adhesive film can be facilitated.

In some embodiments, the surface of the packaging adhesive film on the side close to the battery piece is a flat structure, the surface of the packaging adhesive film on the side away from the battery piece is an uneven structure, or both the surface of the packaging adhesive film on the side close to the battery piece and the surface of the packaging adhesive film on the side away from the battery piece are uneven structures. Therefore, the packaging adhesive film can be prevented from being adhered together between layers to influence normal use when the packaging adhesive film is wound and stored through the uneven surface of the packaging adhesive film.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the figures in which like reference numerals refer to similar elements and which are not to scale unless otherwise specified.

Fig. 1 is a schematic structural view of a photovoltaic module provided in some embodiments herein;

fig. 2 is a schematic top view of an encapsulant film in a photovoltaic module according to some embodiments of the present disclosure;

fig. 3 is a schematic front view of a packaging adhesive film in a photovoltaic module according to some embodiments of the present disclosure;

fig. 4 is a schematic top view of a packaging adhesive film provided with a protrusion according to some embodiments of the present disclosure;

fig. 5 is a schematic front view of a packaging adhesive film provided with a protrusion according to some embodiments of the present disclosure;

fig. 6 is a schematic top view of a packaging adhesive film when the protruding portions are arranged in a grid shape according to some embodiments of the present disclosure;

fig. 7 is a schematic top view of a packaging film with protrusions arranged in an array according to some embodiments of the present disclosure;

FIG. 8 is a schematic top view of an adhesive packaging film with embossments according to some embodiments of the present disclosure;

fig. 9 is a schematic front view of a packaging adhesive film when embossing is provided according to some embodiments of the present disclosure.

Detailed Description

To make the objects, technical solutions and advantages of the embodiments of the present application clearer, embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, it will be appreciated by those of ordinary skill in the art that numerous technical details are set forth in various embodiments of the present application in order to provide a better understanding of the present application. However, the technical solution claimed in the present application can be implemented without these technical details and various changes and modifications based on the following embodiments. The following embodiments are divided for convenience of description, and should not constitute any limitation to the specific implementation manner of the present application, and the embodiments may be mutually incorporated and referred to without contradiction.

In some cases, the thicknesses of the packaging adhesive films for the photovoltaic module on the same side of the cell piece are the same, and the gram weight difference is less than or equal to 10 grams per square meter. With the continuous lowering of the demand of the photovoltaic industry, the overall gram weight of the packaging adhesive film is lowered again and again. Experiments show that when the integral gram weight of the packaging adhesive film with the same thickness is reduced to the limit gram weight, the problem of insufficient adhesive amount can occur in the packaging process of the photovoltaic module, so that the photovoltaic module is blackened in an EL test, and even has the phenomena of fragment, hidden crack, local lamination bubbles and the like.

In the photovoltaic module packaging process, the reasons for local insufficient glue amount include lamination pressure, cover plate surface unevenness, glue overflow and the like. For example, during the lamination process of the photovoltaic module, the edges of the photovoltaic module can bear more pressure, resulting in the flow migration of the encapsulant film at the edges due to extrusion. This may cause an insufficient amount of glue on the edges of the photovoltaic module, which may result in various undesirable phenomena in the photovoltaic module.

In order to adopt low gram weight encapsulation glued membrane while, improve photovoltaic module because of the not enough bad phenomenon that appears of local glued membrane, some embodiments of this application provide an encapsulation glued membrane, through thickening to the local position in edge to increase the gluey volume in edge, increase the local gram weight of edge encapsulation glued membrane promptly. And then solve the problem that the edge of the photovoltaic module has insufficient glue amount in the packaging process. Therefore, under the condition that the gram weight of the packaging adhesive film is in a lower range, the adhesive amount of the local position of the packaging adhesive film is increased, and the problem of insufficient adhesive amount in the packaging process of the photovoltaic module is avoided.

As shown in fig. 1 to 3, some embodiments of the present application provide a photovoltaic module, which includes a battery string 10, an encapsulation film 20 and a cover plate 30, wherein the battery string 10 includes a plurality of battery pieces 11 connected in series in sequence, the encapsulation film 20 covers the surface of the battery string 10, the encapsulation film 20 includes a middle portion 21 having a predetermined thickness and edge portions 22 distributed on two sides of the middle portion 21 along a first direction, the thickness of the two edge portions 22 is greater than that of the middle portion 21, the thickness of each edge portion 22 is gradually increased along a direction away from the middle portion 21, a ratio of the predetermined thickness to the thickness of the battery piece 11 is 1 to 4, and the first direction is perpendicular to the thickness direction of the middle portion 21; the cover plate 30 covers the surface of the packaging adhesive film 20 facing away from the battery string 10.

The middle portion 21 is a portion of the packaging adhesive film 20 with a lower grammage without thickening, and the thickness of the two edge portions 22 is larger than that of the middle portion 21. The two edge portions 22 are distributed on two sides of the middle portion 21 along a first direction (a direction indicated by an arrow X in fig. 2 and 3), which may be a length direction or a width direction of the adhesive packaging film 20. The edges of the two sides of the length direction of the packaging adhesive film 20 can be thickened, or the edges of the two sides of the width direction of the packaging adhesive film 20 can be thickened. In addition, the edges of the periphery of the packaging adhesive film 20 can be thickened. During the preparation of the adhesive packaging film 20, the pressure during the casting of the adhesive packaging film 20 may be controlled to increase the thickness of the edge portion of the adhesive packaging film 20, while the predetermined thickness (the dimension indicated by H1 in fig. 3) of the middle portion 21 of the adhesive packaging film 20 is kept within a lower range. In addition, the two dashed lines in fig. 2 are only schematic representations of the junction of the middle portion 21 and the edge portion 22.

In the photovoltaic module, the cost of the photovoltaic module can be effectively reduced by adopting the cell 11 with proper thickness. In practical cases, the thickness of the cell 11 can be reduced to below 200 μm, based on the demand for continued cost reduction. While the predetermined thickness of the low-gram-weight adhesive packaging film 20 used in some embodiments of the present application, where the low-gram-weight adhesive packaging film is not thickened, is 1 to 4 times the thickness of the battery piece 11, in practical cases, the predetermined thickness of the middle portion 21 of the adhesive packaging film 20 may be 1.5 times, 2 times, 2.5 times, or 3.5 times the thickness of the battery piece 11.

According to the photovoltaic module provided by some embodiments of the present application, under the condition that the preset thickness of the middle portion 21 of the packaging adhesive film 20 is in a lower range, the edge portion 22 of the packaging adhesive film 20 is thickened, so that the thicknesses of the two edge portions 22 of the packaging adhesive film 20 are greater than the preset thickness of the middle portion 21, that is, the local gram weight of the edge portion 22 of the packaging adhesive film 20 is increased. Therefore, in the packaging process of the photovoltaic module, the bad phenomenon caused by insufficient glue at the edge of the photovoltaic module is avoided. Moreover, the thickness of each edge portion 22 of the packaging adhesive film 20 gradually increases in a direction away from the middle portion 21, so that the edge portion 22 of the packaging adhesive film 20 can be more uniformly filled between the battery piece 11 and the cover plate 30 when melted and cross-linked to overflow in the direction away from the middle portion 21. Through thickening to encapsulation glued membrane 20 edge, can improve the bad phenomenon that photovoltaic module local position appears when reducing the grammes per square metre of encapsulation glued membrane 20.

In some embodiments of the present application, a plurality of battery pieces 11 may be arranged at intervals along the first direction, or a plurality of battery pieces 11 are arranged in sequence along the first direction and two adjacent battery pieces 11 are partially stacked together, and each battery piece 11 has a thickness of 110 to 160 micrometers.

The cell string 10 in the photovoltaic module generally adopts two cell connection structures, one is to arrange the cells 11 at intervals, so that a certain distance is provided between two adjacent cells 11. In this case, the distance between two adjacent battery pieces 11 leaves a blank area and cannot absorb solar energy caused by light. Another method is to partially overlap the battery plates 11, so that the adjacent two battery plates 11 are partially overlapped. In this way, no blank area is left between two adjacent battery pieces 11, thereby improving the photoelectric conversion efficiency of the photovoltaic module. In addition, two adjacent battery pieces 11 can be electrically connected through a solder strip or a conductive adhesive, and the battery pieces 11 can be arranged in parallel with respect to the cover plate 30 or can be arranged in an inclined manner at a certain angle with respect to the cover plate 30.

By keeping the thickness of each cell 11 to be 110-160 micrometers, the requirement of reducing cost of the photovoltaic module can be effectively met, and meanwhile, the photoelectric conversion efficiency of the photovoltaic module can be prevented from being influenced due to the fact that the thickness of each cell 11 is too small. In practical cases, the thickness of each cell piece 11 may be 110 microns, 160 microns, or 130 microns or 140 microns.

In some embodiments of the present disclosure, a ratio of the predetermined thickness of the middle portion 21 of the packaging adhesive film 20 to the thickness of the battery piece 11 may be 1.9 to 2.7; and/or the predetermined thickness of the middle portion 21 of the packaging adhesive film 20 may be 210 micrometers to 420 micrometers, and the maximum thickness (dimension indicated by H2 in fig. 3) of each edge portion 22 does not exceed 600 micrometers.

That is, in a practical situation, the preset thickness of the middle portion 21 of the adhesive packaging film 20 may be greater than or equal to 1.9 times of the thickness of the battery piece 11 and less than or equal to 2.7 times of the thickness of the battery piece 11, for example, the preset thickness of the middle portion 21 may be 2.1 times, 2.4 times, 2.5 times or 2.6 times of the thickness of the battery piece 11. The preset thickness is 1.9-2.7 times of the thickness of the battery piece 11, so that the overall gram weight of the packaging adhesive film 20 is adapted to the thickness of the battery piece 11, and for a thicker battery piece 11, the packaging adhesive film 20 also has a proper adhesive amount for bonding, thereby being beneficial to ensuring the reliability of the battery piece 11.

Alternatively, the predetermined thickness of the middle portion 21 of the adhesive packaging film 20 may be 210 to 420 micrometers, and the maximum thickness of each edge portion 22 may not exceed 600 micrometers. Therefore, the phenomenon that the gap is filled between the position with the excessive glue amount and the position with the small glue amount due to the excessive thickness and the excessive glue amount of the edge part 22 can be avoided, and therefore the bad phenomena such as air bubbles and the like in the photovoltaic module packaging process are avoided. Meanwhile, keeping the thickness of each edge portion 22 within a certain range is advantageous in saving the cost of the adhesive packaging film 20.

The preset thickness of the middle part 21 of the packaging adhesive film 20 can be set to be 210 micrometers-420 micrometers within the range of more than or equal to 1.9 times of the thickness of the battery piece 11 and less than or equal to 2.7 times of the thickness of the battery piece 11, and the maximum of each edge part 22 is not more than 600 micrometers. Therefore, the packaging adhesive film 20 can adapt to bonding of the battery pieces 11 with different thicknesses, and the using amount of the packaging adhesive film 20 can be saved, so that the cost of the packaging adhesive film 20 is saved.

In addition, one side edges of the two battery pieces 11 located at the outermost sides in the first direction, which are far away from each other, are respectively covered inside the two edge portions 22 of the packaging adhesive film 20, and the width (dimension W in fig. 2) of each edge portion 22 in the first direction may be 40 mm to 80 mm.

In this way, it is avoided that the width of each edge portion 22 in the first direction is too small to accommodate the filling at the edges of the photovoltaic module. At the same time, the phenomenon that the width of each edge portion 22 in the first direction is too large to cause an excessive amount of glue can be avoided.

As shown in fig. 3, each edge portion 22 may include a flat surface 221 and an arc-shaped surface 222 which are oppositely arranged in the thickness direction, the flat surface 221 is connected with a surface of the middle portion 21 away from the battery piece 11, and one end of the arc-shaped surface 222, which is closer to the flat surface 221, is connected with a surface of the middle portion 21 close to the battery piece 11.

By providing the arcuate surface 222 in each edge portion 22, the thickness of each edge portion 22 can be maintained in a gradual increasing trend. Thus, after the end of the arc-shaped surface 222 closer to the plane 221 meets the surface of the middle portion 21 closer to the cell piece 11, the thickness of each edge portion 22 shows a tendency to gradually increase in the direction away from the middle portion 21. Note that the thickness direction of each edge portion 22 is parallel to the thickness direction of the intermediate portion 21.

In other embodiments, each edge portion 22 may also take the form of a flat surface 221 and a bevel surface opposite in the thickness direction, or two bevel surfaces opposite in the thickness direction, or two arc-shaped surfaces 222 opposite in the thickness direction. In the case where each of the edge portions 22 takes a flat surface 221 and an inclined surface which are opposed in the thickness direction, the flat surface 221 may meet a face of the intermediate portion 21 which is away from the battery piece 11, and an end of the inclined surface which is closer to the flat surface 221 meets a face of the intermediate portion 21 which is close to the battery piece 11. In the case where each of the edge portions 22 takes two inclined surfaces opposed in the thickness direction, one ends of the two inclined surfaces are close to each other and the other ends of the two inclined surfaces are distant from each other, and the ends of the two inclined surfaces close to each other are respectively in contact with the two surfaces opposed in the thickness direction of the intermediate portion 21. In the case where each of the edge portions 22 takes two arc-shaped faces 222 opposing in the thickness direction, one ends of the two arc-shaped faces 222 are close to each other, the other ends of the two arc-shaped faces 222 are distant from each other, and the ends of the two arc-shaped faces 222 close to each other are respectively in contact with two surfaces of the intermediate portion 21 opposing in the thickness direction.

In addition, as shown in fig. 4 to 7, a plurality of protruding portions 211 may be disposed on one surface of the middle portion 21 close to the cell piece 11, each protruding portion 211 is protruding from the middle portion 21 in the thickness direction of the middle portion 21, and the arrangement shape of the plurality of protruding portions 211 on one surface of the middle portion 21 close to the cell piece 11 is in a discrete strip shape, a grid shape, or an array shape.

The problem of filling gaps due to the uneven cover at the intermediate portion 21 can be solved by providing a plurality of protrusions 211 on the side of the intermediate portion 21 adjacent to the cell 11. Meanwhile, under the condition that the packaging adhesive film 20 has a relatively low thickness, the bonding strength at the middle position of the packaging adhesive film 20 is reduced in the packaging process, which can cause the problems of hidden cracking, breaking and the like of the cell in the laminating process of the photovoltaic module. In order to enhance the bonding strength at the middle position of the packaging adhesive film 20 during the packaging process, the middle portion 21 of the packaging adhesive film 20 may be thickened, that is, a plurality of protrusions 211 are disposed on one side of the middle portion 21 close to the battery piece 11. And the position of the convex part 211 can be made to correspond to the gap of the cell pieces 11 or the overlapping position of the cell pieces 11 in the process of packaging the photovoltaic module.

As shown in fig. 4 and 5, the plurality of protrusions 211 may be arranged in a separate strip shape on a surface of the middle portion 21 close to the cell 11, that is, each protrusion 211 is arranged in a strip shape, and the plurality of protrusions 211 are arranged at intervals on a surface of the middle portion 21 close to the cell 11. As shown in fig. 6, the plurality of protruding portions 211 may be arranged in a grid shape on a side of the middle portion 21 close to the cell 11, that is, the plurality of protruding portions 211 are arranged in a strip shape, and the plurality of protruding portions 211 are divided into two portions, and the two portions are respectively arranged on a side of the middle portion 21 close to the cell 11 at intervals along different directions. As shown in fig. 7, the plurality of protrusions 211 may be arranged in an array on a side of the middle portion 21 close to the cell piece 11, that is, each protrusion 211 is arranged in a block shape, and the plurality of protrusions 211 are arranged in an array on a side of the middle portion 21 close to the cell piece 11. It should be noted that the two dashed lines in fig. 4, 6 and 7 are only schematic representations of the junction between the middle portion 21 and the edge portion 22.

In some embodiments of the present application, each protrusion 211 may be disposed at a gap or a superposition of two battery sheets 11, and a height of each protrusion 211 in a thickness direction of the middle portion 21 is 10% to 40% of a preset thickness.

In this way, the height of each protrusion 211 in the thickness direction of the middle portion 21 can be prevented from being too low, and the packaging adhesive film 20 can not have a good filling effect in the packaging process. It is also avoided that the height of each protrusion 211 in the thickness direction of the middle portion 21 is too high, and the waste caused by too large difference between the thickness of the packaging adhesive film 20 where the protrusion 211 is provided and the thickness where the protrusion 211 is not provided is avoided.

For example, in practical cases, the thickness (dimension shown by H3 in fig. 5) of the packaging adhesive film 20 at the position where the convex portion 211 is provided may be 300 to 500 micrometers.

In some embodiments of the present application, the arrangement shape of the side of the middle portion 21 close to the cell piece 11 is a discrete strip, and the plurality of protrusions 211 may be distributed on the middle portion 21 at intervals along the second direction (the direction indicated by the arrow Y in fig. 4 and 5), and each protrusion 211 has a width in the second direction of 160 mm to 230 mm.

By having each protrusion 211 occupy a width on the intermediate portion 21, the intermediate portion 21 can be made to provide a desired amount of glue during the packaging process to better accommodate the adhesion at the gap or stack of the battery pieces 11.

In some embodiments of the present application, the second direction may be parallel to the first direction, and a cross-sectional shape of each protrusion 211 in the second direction is a rectangle.

By setting the cross-sectional shape of each protrusion 211 in the second direction to be rectangular, the preparation of the packaging adhesive film 20 can be facilitated, and the molded packaging adhesive film 20 can be formed into the protrusion 211 with a regular shape by casting using a mold having an extrusion port with a regular shape.

In some embodiments of the present application, a surface of one side of the packaging adhesive film 20 close to the battery piece 11 is a flat structure, a surface of one side of the packaging adhesive film 20 far away from the battery piece 11 is an uneven structure, or both the surface of one side of the packaging adhesive film 20 close to the battery piece 11 and the surface of one side far away from the battery piece 11 are uneven structures.

The uneven structure means that the surface of the packaging adhesive film 20 on the side away from the battery piece 11 is not planar, but is provided with inverted cone-shaped, well-shaped or other uneven embossments. By arranging the embossing on the surface of the packaging adhesive film 20, the packaging adhesive film 20 can be prevented from being adhered together between layers when being wound and stored, so that the normal use is not influenced. As shown in fig. 8 and 9, the front surface and the back surface of the adhesive packaging film 20 may be provided with uneven structures.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples for carrying out the present application, and that various changes in form and details may be made therein without departing from the spirit and scope of the present application in practice.

Claims (10)

1. A photovoltaic module, comprising:

the battery string comprises a plurality of battery pieces which are sequentially connected in series;

the packaging adhesive film covers the surface of the battery string, the packaging adhesive film comprises a middle part with preset thickness and edge parts distributed on two sides of the middle part along a first direction, the thickness of the two edge parts is larger than that of the middle part, the thickness of each edge part is gradually increased along the direction far away from the middle part, the ratio of the preset thickness to the thickness of the battery piece is 1-4, and the first direction is perpendicular to the thickness direction of the middle part;

and the cover plate covers the surface of the packaging adhesive film, which deviates from the battery string.

2. The photovoltaic module of claim 1, wherein:

the plurality of battery pieces are arranged at intervals along the first direction, or the plurality of battery pieces are sequentially arranged along the first direction, two adjacent battery pieces are partially overlapped together, and the thickness of each battery piece is 110-160 micrometers.

3. The photovoltaic module of claim 1, wherein:

the ratio of the preset thickness to the thickness of the battery piece is 1.9-2.7; and/or

The preset thickness is 210 micrometers to 420 micrometers, and the maximum thickness of each edge part is not more than 600 micrometers.

4. The photovoltaic module of claim 2, wherein:

the edges of one side, far away from each other, of the two battery pieces located on the outermost side in the first direction are covered inside the two edge portions respectively, and the width of each edge portion in the first direction is 40-80 mm.

5. The photovoltaic module of claim 1, wherein:

each edge part comprises a plane and an arc-shaped surface which are oppositely arranged along the thickness direction, the plane is connected with one surface of the middle part, which is far away from the battery piece, and one end, which is close to the plane, of the arc-shaped surface is connected with one surface, which is close to the battery piece, of the middle part.

6. The photovoltaic module of any one of claims 1 to 5, wherein:

the mid portion is close to the one side of battery piece is provided with a plurality of bulges, every the bulge is followed the thickness direction of mid portion certainly the protruding setting of mid portion is a plurality of the bulge is in the mid portion is close to the shape of arranging of the one side of battery piece presents for discrete strip, latticed or array form.

7. The photovoltaic module of claim 6, wherein:

each protruding part is arranged at the position corresponding to the gap or the overlapping position of the two battery pieces, and the height of each protruding part in the thickness direction of the middle part is 10% -40% of the preset thickness.

8. The photovoltaic module of claim 6, wherein:

the arrangement shape of one surface of the plurality of the convex parts, which is close to the battery piece, in the middle part is in a discrete strip shape, the plurality of the convex parts are distributed on the middle part at intervals along a second direction, and the width of each convex part in the second direction is 160-230 mm.

9. The photovoltaic module of claim 8, wherein:

the second direction is parallel to the first direction, and a cross-sectional shape of each of the projections in the second direction is rectangular.

10. The photovoltaic module of claim 1, wherein:

the surface of one side, close to the battery piece, of the packaging adhesive film is of a flat structure, the surface of one side, far away from the battery piece, of the packaging adhesive film is of an uneven structure, or the surface of one side, close to the battery piece, of the packaging adhesive film and the surface of one side, far away from the battery piece, of the packaging adhesive film are of uneven structures.

Images