Packaging adhesive film and photovoltaic module

Abstract

The utility model discloses a packaging adhesive film and a photovoltaic assembly, the packaging adhesive film comprises a first sub-layer and a second sub-layer connected with the first sub-layer, the first sub-layer and the second sub-layer are made of different materials, and the first sub-layer is located below the second sub-layer; the first sub-layer, or the first sub-layer and the second sub-layer are provided with at least two raised parts, and the at least two raised parts are arranged along the width direction of the packaging adhesive film. According to the utility model, the first sub-layer is provided with at least two protruding parts, and the strength of the first sub-layer can be improved through the protruding parts; or, at least two protruding parts are arranged on the first sub-layer and the second sub-layer and arranged in the width direction of the packaging adhesive film, the strength of the first sub-layer and the second sub-layer can be improved through the protruding parts, the subfissure phenomenon of the battery piece can be effectively improved subsequently, and therefore the assembly yield is increased; and the slippage phenomenon between the front cover plate and / or the back cover plate and the battery piece can be prevented.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaics, and more specifically, to a packaging adhesive film and a photovoltaic component. Background Art

[0002] Solar cell encapsulation materials, which are developing rapidly in the field of solar photovoltaics, have become one of the hot spots in the global photovoltaic field. In recent years, the production of solar cells in my country has increased at an astonishing rate, and the research and development of related encapsulation materials has become increasingly important. Solar cell encapsulation films play an important role in the field of solar cells in my country.

[0003] Conventional encapsulation films do not have an anti-slip structure on their surface, which may cause the encapsulation films to slip during the lamination process, thereby causing the battery cells to slip, which will subsequently cause the risk of hidden cracks in the components, reducing the reliability and yield of the components. Therefore, this is a technical problem that urgently needs to be solved in this field. Utility Model Content

[0004] In view of this, the utility model provides a packaging film to solve the problem that the packaging film may slip during the lamination process, thereby causing the battery cell to slip and subsequently causing the risk of hidden cracks in the component.

[0005] In a first aspect, the present application provides a packaging film, comprising a first sublayer and a second sublayer connected to the first sublayer, the first sublayer and the second sublayer are made of different materials, and the first sublayer is located below the second sublayer;

[0006] At least two protrusions are arranged on the first sub-layer, or on the first sub-layer and the second sub-layer, and at least two of the protrusions are arranged along the width direction of the packaging film.

[0007] Optionally, a corrugated structure is formed between at least two of the raised portions.

[0008] Optionally, a thickness ratio of the first sublayer to the second sublayer is in a range of 0.1-0.4.

[0009] Optionally, the first sublayer is provided with anti-slip patterns on a side away from the second sublayer, the anti-slip patterns include first stripes and second stripes connected to the first stripes, and an extension direction of the first stripes intersects with an extension direction of the second stripes.

[0010] Optionally, the number of the first stripes and the number of the second stripes are both multiple, and the multiple first stripes and the multiple second stripes form a tic-tac-toe pattern.

[0011] In a second aspect, the present application provides a photovoltaic module, including a front cover plate, a first packaging film, a battery string, a second packaging film and a back cover plate arranged in a stacked manner; the battery string includes at least two battery cells;

[0012] The first encapsulation film and the second encapsulation film both include a first sublayer and a second sublayer connected to the first sublayer, the first sublayer and the second sublayer are made of different materials, and the first sublayer is located close to the battery cell;

[0013] At least two protrusions are disposed on the first sub-layer, or the first sub-layer and the second sub-layer, and the at least two protrusions are arranged along the width direction of the first packaging film and / or the second packaging film.

[0014] Optionally, the cell comprises a semiconductor substrate, the semiconductor substrate comprises at least two first fine grid lines located on a first partition, and the at least two first fine grid lines are arranged along a length direction of the semiconductor substrate and extend along a width direction of the semiconductor substrate;

[0015] At least part of the first fine gate lines are respectively provided with welding spots on both sides along the length direction of the semiconductor substrate; and at least two welding spots are arranged along the width direction of the semiconductor substrate.

[0016] Optionally, two second partitions are further included, and along the length direction of the semiconductor substrate, the first partition is located between the two second partitions;

[0017] The second partition is provided with a connection structure arranged along the width direction of the semiconductor substrate, each of the connection structures includes a first anti-breaking gate line and a second anti-breaking gate line arranged opposite to each other, the first anti-breaking gate line and the second anti-breaking gate line respectively extend along the length direction of the semiconductor substrate, the first anti-breaking gate line and the second anti-breaking gate line are connected to the welding point close to the side of the first fine gate line, at least one second fine gate line is connected between the first anti-breaking gate line and the second anti-breaking gate line, and the second fine gate line is electrically connected to the first fine gate line through a connecting line.

[0018] Optionally, two adjacent battery cells are electrically connected via a welding wire, and the orthographic projection of the welding wire on the plane where the front cover plate is located is located within the orthographic projection of the raised portion on the plane where the front cover plate is located.

[0019] Compared with the prior art, the encapsulation film and photovoltaic module provided by the utility model achieve at least the following beneficial effects:

[0020] The utility model provides an encapsulation film and a photovoltaic module, wherein the encapsulation film comprises a first sublayer and a second sublayer connected to the first sublayer, the first sublayer and the second sublayer are made of different materials, and the first sublayer is located below the second sublayer; at least two protrusions are provided on the first sublayer, and the strength of the first sublayer can be improved by the protrusions; or at least two protrusions are provided on the first sublayer and the second sublayer, and the at least two protrusions are arranged along the width direction of the encapsulation film, and the strength of the first sublayer and the second sublayer can be improved by the protrusions, which can not only effectively improve the hidden cracking phenomenon of the battery cells, thereby improving the module yield, but also prevent the front cover plate and / or the back cover plate from slipping with the battery cells.

[0021] Of course, any product implementing the present utility model does not necessarily need to achieve all of the above-mentioned technical effects at the same time.

[0022] Other features and advantages of the present invention will become apparent from the following detailed description of exemplary embodiments of the present invention with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the present invention.

[0024] Figure 1 This is a structural schematic diagram of a packaging film provided by the utility model;

[0025] Figure 2 This is a structural schematic diagram of another packaging film provided by the utility model;

[0026] Figure 3 It is a structural schematic diagram of another packaging film provided by the utility model;

[0027] Figure 4 It is a structural schematic diagram of a photovoltaic assembly provided by the utility model;

[0028] Figure 5 This is an exploded diagram of a first packaging film and a battery cell provided by the utility model;

[0029] Figure 6 yes Figure 5 A partial enlarged view of the middle part;

[0030] Figure 7 This is a structural schematic diagram of another battery cell provided by the utility model;

[0031] Figure 8 yes Figure 7 A partial enlarged view of point B in the middle;

[0032] Fig. 9It is a cross-sectional schematic diagram of a photovoltaic module provided by the utility model;

[0033] Fig.10 It is a structural schematic diagram of the welding wire and the battery cell provided by the utility model. DETAILED DESCRIPTION

[0034] Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that unless otherwise specifically stated, the relative arrangement of components and steps, numerical expressions and numerical values ​​set forth in these embodiments do not limit the scope of the present invention.

[0035] The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the present invention, its application, or uses.

[0036] Technologies, methods, and equipment known to ordinary technicians in the relevant art may not be discussed in detail, but where appropriate, the technologies, methods, and equipment should be considered as part of the specification.

[0037] In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not limiting. Therefore, other examples of the exemplary embodiments may have different values.

[0038] It should be noted that like reference numerals and letters refer to similar items in the following figures, and therefore, once an item is defined in one figure, it need not be further discussed in subsequent figures.

[0039] Figure 1 This is a structural schematic diagram of a packaging film provided by the utility model; Figure 2 This is a schematic diagram of the structure of another packaging film provided by the utility model; see Figure 1 and Figure 2 As shown, this embodiment provides a packaging film, including a first sublayer 1 and a second sublayer 2 connected to the first sublayer 1, the first sublayer 1 and the second sublayer 2 are made of different materials, and the first sublayer 1 is located below the second sublayer 2; at least two protrusions 11 are arranged on the first sublayer 1, or the first sublayer 1 and the second sublayer 2, and the at least two protrusions 11 are arranged along the width direction of the packaging film.

[0040] Specifically, continue to refer to Figure 1As shown, the encapsulation film includes a first sublayer 1 and a second sublayer 2, the first sublayer 1 is connected to the second sublayer 2, the first sublayer 1 and the second sublayer 2 are arranged relatively to each other, the first sublayer 1 can be located below the second sublayer 2, such as the top surface of the first sublayer 1 is bonded to the bottom surface of the second sublayer 2, it can be understood that: the first sublayer 1 can be a connecting inner layer, and the second sublayer 2 can be a protective outer layer; the first sublayer 1 and the second sublayer 2 can be a double-layer film formed by co-extrusion. The materials of the first sublayer 1 and the second sublayer 2 are different. For example, the material of the first sublayer 1 can be polyethylene octene co-elastomer (POE), and the material of the second sublayer 2 can be ethylene-vinyl acetate copolymer (EVA). Both ethylene-vinyl acetate copolymer (EVA) and polyethylene octene co-elastomer (POE) have the characteristics of high light transmittance, UV resistance and high temperature resistance. Among them, ethylene-vinyl acetate copolymer is the most commonly used film material for photovoltaic modules. Ethylene-vinyl acetate copolymer has the advantages of excellent bonding performance, low melting temperature, good melt fluidity and softness, low cost, and easy construction. Ethylene-vinyl acetate copolymer can reduce high crystallinity and improve toughness, impact resistance, filler compatibility and heat sealing performance due to the introduction of vinyl acetate monomer in the molecular chain. The molecular structure of polyethylene octene co-elastomer makes it have excellent mechanical properties, rheological properties and UV resistance. The ability of polyethylene octene co-elastomer to isolate water and oxygen is better than that of ethylene-vinyl acetate copolymer.

[0041] Continue to refer to Figure 1 As shown, a plurality of raised portions 11 are provided on the first sublayer 1. The plurality of raised portions 11 may be arched toward the side close to the second sublayer 2. The plurality of raised portions 11 are arranged along the width direction of the packaging film. The plurality of raised portions 11 may be evenly distributed on the first sublayer 1. For example, the plurality of raised portions 11 may be evenly distributed on the bottom surface of the first sublayer 1, or the plurality of raised portions 11 may be evenly distributed on the bottom surface of the first sublayer 1 and the top surface of the first sublayer 1. The strength of the first sublayer 1 may be improved by the raised portions 11. During subsequent lamination, the first sublayer 1 may be located on the side close to the battery cell (not shown in the figure). By changing the structure of the first sublayer 1, the hidden cracking phenomenon of the battery cell may be effectively improved, thereby improving the component yield.

[0042] Continue to refer to Figure 2As shown, a plurality of raised portions 11 are provided on both the first sublayer 1 and the second sublayer 2. For example, the plurality of raised portions 11 in the first sublayer 1 may be arched toward the side close to the second sublayer 2, the plurality of raised portions 11 in the first sublayer 1 corresponds to the plurality of raised portions 11 in the second sublayer 2, the plurality of raised portions 11 are arranged along the width direction of the packaging film, and the plurality of raised portions 11 may be evenly distributed on the first sublayer 1 and the second sublayer 2. For example, the plurality of raised portions 11 may be evenly distributed on the bottom surface of the first sublayer 1, the interface between the first sublayer 1 and the second sublayer 2, and the top surface of the second sublayer 2. The strength of the first sublayer 1 and the second sublayer 2 may be improved by the raised portions 11, which may not only effectively improve the hidden cracking of the battery cell, thereby improving the component yield, but also prevent the front cover plate and / or the back cover plate from slipping with the battery cell.

[0043] It should be noted that the spacing between the two adjacent protrusions 11 can be equal spacing, and the spacing between the two adjacent protrusions 11 can be set according to actual conditions, such as the spacing between two adjacent welding wires (not shown in the figure), which is not limited in this embodiment.

[0044] In the above two embodiments, the interface between the first sublayer 1 and the second sublayer 2 can be a curved surface to increase the contact area between the first sublayer 1 and the second sublayer 2, so that the first sublayer 1 and the second sublayer 2 are more firmly bonded.

[0045] Compared with the prior art, the encapsulation film provided in this embodiment achieves at least the following beneficial effects:

[0046] The packaging film provided in this embodiment includes a first sublayer 1 and a second sublayer 2 connected to the first sublayer 1, the first sublayer 1 and the second sublayer 2 are made of different materials, and the first sublayer 1 is located below the second sublayer 2; at least two protrusions 11 are provided on the first sublayer 1, and the strength of the first sublayer 1 can be improved by the protrusions 11; or, at least two protrusions 11 are provided on the first sublayer 1 and the second sublayer 2, and at least two protrusions 11 are arranged along the width direction of the packaging film, and the strength of the first sublayer 1 and the second sublayer 2 can be improved by the protrusions 11, which can not only effectively improve the hidden cracking phenomenon of the battery cell, thereby improving the component yield, but also prevent the front cover plate and / or the back cover plate from slipping with the battery cell.

[0047] In an alternative embodiment, Figure 3 It is a structural schematic diagram of another packaging film provided by the utility model; Figure 1-Figure 3 As shown, at least two protrusions 11 form a corrugated structure, which can not only increase the surface area of ​​the packaging film, improve its mechanical strength and rigidity, but also adjust the optical properties of the packaging film, such as changing its reflection and transmission characteristics.

[0048] Optionally, the thickness ratio of the first sublayer 1 to the second sublayer 2 is in the range of 0.1-0.4.

[0049] Specifically, continue to refer to Figure 1 and Figure 2 As shown, on the one hand, when the thickness ratio of the first sublayer 1 to the second sublayer 2 is lower than 0.1, the reliability of the encapsulation film will be reduced; on the other hand, when the thickness ratio of the first sublayer 1 to the second sublayer 2 is higher than 0.4, not only can the thickness of the encapsulation film be too high, thereby reducing the light transmittance, thereby affecting the power generation performance, but also when the material of the first sublayer 1 is polyethylene octene co-elastomer, and the material of the second sublayer 2 is ethylene-vinyl acetate copolymer, since the cost of polyethylene octene co-elastomer is higher than that of ethylene-vinyl acetate copolymer, therefore, the thickness ratio of the first sublayer 1 to the second sublayer 2 is designed to be 0.1-0.4, which can not only improve the reliability of the encapsulation film, but also avoid the thickness of the encapsulation film, thereby improving the light transmittance, thereby improving the power generation performance, and at the same time reducing the overall cost of the film. Optionally, the thickness ratio of the first sublayer 1 to the second sublayer 2 can range from 0.2-0.35. Specifically, the thickness ratio of the first sublayer 1 to the second sublayer 2 can be 0.1, 0.2 or 0.4.

[0050] In an alternative embodiment, continue to refer to Figure 3 As shown, the first sublayer 1 is provided with an anti-slip pattern 3 on the side away from the second sublayer 2, and the anti-slip pattern 3 includes a first stripe 31 and a second stripe 32 connected to the first stripe 31, and the extension direction of the first stripe 31 intersects with the extension direction of the second stripe 32. Specifically, the first stripe 31 can be a transverse stripe, and the second stripe 32 can be a longitudinal stripe. Of course, according to actual conditions, the first stripe 31 can be a longitudinal stripe, and the second stripe 32 can be a transverse stripe. The extension directions of the first stripe 31 and the second stripe 32 intersect. Optionally, the extension directions of the first stripe 31 and the second stripe 32 are perpendicular. On the basis of at least two protrusions 11 being provided on the first sublayer 1, or the first sublayer 1 and the second sublayer 2, the risk of the battery cell 61 slipping can be reduced by the cooperation between the first stripe 31 and the second stripe 32.

[0051] In an optional embodiment, the number of the first stripes 31 and the number of the second stripes 32 are both multiple, and the multiple first stripes 31 and the multiple second stripes 32 form a tic-tac-toe pattern.

[0052] Specifically, continue to refer to Figure 3As shown, the number of the first stripes 31 and the number of the second stripes 32 are both multiple, two adjacent first stripes 31 are parallel to each other, and two adjacent second stripes 32 are parallel to each other. Specifically, taking the example that the first stripes 31 can be transverse stripes and the second stripes 32 can be longitudinal stripes, two adjacent transverse stripes are parallel to each other, and two adjacent longitudinal stripes are parallel to each other. The multiple transverse stripes can be evenly distributed on the bottom surface of the first sublayer 1, and the multiple longitudinal stripes can be evenly distributed on the bottom surface of the first sublayer 1. The multiple transverse stripes and the multiple longitudinal stripes are perpendicular to each other, and the multiple transverse stripes and the multiple longitudinal stripes form a tic-tac-toe pattern. Through the mutual coordination between the multiple transverse stripes, the multiple longitudinal stripes and the multiple protrusions 11, not only can the anti-slip phenomenon between the encapsulation film and the battery cell 61 be achieved before lamination, but also the gram weight of the encapsulation film can be effectively reduced, thereby reducing the component cost.

[0053] Figure 4 It is a structural schematic diagram of a photovoltaic assembly provided by the utility model; Figure 5 This is an exploded diagram of a first packaging film and a battery cell provided by the utility model; Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, this embodiment provides a photovoltaic module 100, including a front cover plate 4, a first packaging film 5, a battery string 6, a second packaging film 7 and a back cover plate 8 which are stacked; the battery string 6 includes at least two battery cells 61; the first packaging film 5 and the second packaging film 7 both include a first sublayer 1 and a second sublayer 2 connected to the first sublayer 1, the first sublayer 1 and the second sublayer 2 are made of different materials, and the first sublayer 1 is located on a side close to the battery cell 61; the first sublayer 1, or the first sublayer 1 and the second sublayer 2 are provided with at least two protrusions 11, and the at least two protrusions 11 are arranged along the width direction of the first packaging film 5 and / or the second packaging film 7.

[0054] Specifically, refer to Figure 4As shown, in this embodiment, the photovoltaic module 100 includes a front cover plate 4, a first packaging film 5, a battery string 6, a second packaging film 7 and a back cover plate 8 arranged in a stacked manner, wherein the front cover plate 4 can be glass, and the glass has a high light transmittance, and its light transmittance can reach more than 92%. Generally, tempered embossed glass is used, and the thickness range can be 1.6mm-3.2mm. The thickness of the glass can be 1.6mm, 2.0mm, 2.4mm, 2.7mm, 3mm, 3.1mm or 3.2mm. The thickness of the glass can be set according to actual conditions, and this embodiment does not specifically limit this; within the wavelength range of 380 to 1100nm of the spectral response of the solar cell, the light transmittance can reach more than 91%. The glass can be conventional flat glass, and the shape of the glass is no longer limited in this embodiment, and can be square, round or other shapes, as long as it can achieve the purpose of this embodiment. Of course, the glass can also be a special-shaped glass, such as curved glass.

[0055] The back cover 8 can be made of glass or a back panel. The back panel can be divided into a double-sided fluorine film back panel, a single-sided fluorine film back panel and a fluorine-free back panel according to whether it contains fluorine. Among them, the double-sided fluorine film back panel can be a TPT type back panel (PVF / PET / PVF), a KPK type back panel (PVDF / PET / PVDF) and a KPF type back panel (PVDF / PET / fluorine film). Taking the KPK type back panel as an example, the difference between the KPK type back panel and the TPT type back panel is that the inner and outer fluorine films are replaced by PVDF (polyvinylidene fluoride) film. Instead of PVF (polyvinyl fluoride) film, it has high mechanical strength, good radiation resistance and good chemical stability; PET in TPT type backplane refers to polyethylene terephthalate plastic film; single-sided fluorine film backplane can be TPE type backplane (PVF / PET / PE) and KPE type backplane (PVDF / PET / PE), among which PE refers to polyolefin film; fluorine-free backplane can be PPE type backplane, and the outer layer of PET in PPE type backplane needs to be strengthened with UV resistance and weather resistance and bonded with adhesive.

[0056] The back cover plate 8 is used to protect the internal packaging materials and batteries from mechanical damage and external environmental corrosion. It also has good insulation performance, which largely determines the working life of the components. It has excellent weather resistance, low water vapor permeability, good electrical insulation, and a certain bonding strength. The thickness of the back cover plate 8 can range from 0.2 to 3.2 mm. The thickness of the back cover plate 8 can be 0.2 mm, 1 mm, 2 mm, 3 mm or 3.2 mm. The cost of the back cover plate 8 using a back plate is relatively low compared to the cost of glass. According to actual conditions, the back cover plate 8 is selected to be a back plate or glass.

[0057] Combination Figure 1 and Figure 2As shown, the first encapsulation film 5 and the second encapsulation film 7 both include a first sublayer 1 and a second sublayer 2 connected to the first sublayer 1. For example, the top surface of the first sublayer 1 and the bottom surface of the second sublayer 2 can be bonded together by hot pressing. The first sublayer 1 and the second sublayer 2 are made of different materials. The first sublayer 1 can be located on the side close to the battery cell 61. The material of the first sublayer 1 can be polyethylene octene elastomer (POE), and the material of the second sublayer 2 can be ethylene-vinyl acetate copolymer (EVA). It can be understood that the first sublayer 1 can be a POE film, and the second sublayer 2 can be an EVA film. Generally, the fluidity of the POE film is better than that of the EVA film. The double-layer film formed by co-extrusion can reduce the edge POE film from being squeezed out during lamination, thereby preventing the problem of lack of glue at the edge of the component, reducing the risk of delamination and bubbles at the edge of the component before and after aging, and thus improving the reliability and life of the component.

[0058] The battery string 6 includes a plurality of battery cells 61, which can be busbarless battery cells and busbar-connected battery cells, wherein busbarless battery cells and busbar-connected battery cells are widely used in solar panels. Busbarless battery cells have the advantages of high conversion efficiency and good stability, and are relatively easy to manufacture; while busbar-connected battery cells have better adjustment range and stability, but are more difficult to manufacture. In practical applications, different types of battery cells can be selected according to specific needs to achieve the best power generation effect. The cell specifications include 156.75mm (156.75mm×156.75mm), 125mm (125mm×125mm), 182mm (182mm×182mm), and 210mm (210mm×210mm). Among them, 156.75mm×156.75mm is the most common cell size. The 125mm×125mm cell is mainly used in photovoltaic power stations and BIPV fields. The 182mm×182mm and 210mm×210mm cell sizes are larger in size with higher efficiency and output power.

[0059] Combination Figure 1As shown, since the first sublayer 1 is located on the side close to the battery cell 61, a plurality of protrusions 11 are arranged on the first sublayer 1, and the plurality of protrusions 11 can be arched toward the side away from the battery cell 61, and the plurality of protrusions 11 are arranged along the width direction of the packaging film, and some of the protrusions 11 can subsequently correspond to the welding wire 9. It can be understood that some of the protrusions 11 can cover the welding wire (not shown in the figure), and the plurality of protrusions 11 can be evenly distributed on the first sublayer 1. The strength of the first sublayer 1 can be improved by the protrusions 11, and the slip phenomenon between the first packaging film 5 and the battery cell 61 and between the battery cell 61 and the second packaging film 7 can be effectively improved before lamination; during subsequent lamination, since the first sublayers 1 of the first packaging film 5 and the second packaging film 7 are both located on the side close to the battery cell 61, the hidden crack phenomenon of the battery cell 61 can be effectively improved by changing the structure of the first sublayer 1, thereby improving the component yield.

[0060] Combination Figure 2 and Figure 5 As shown, a plurality of protrusions 11 are provided on both the first sublayer 1 and the second sublayer 2. The plurality of protrusions 11 can be arched toward the side away from the battery cell 61. The protrusions 11 in the first sublayer 1 correspond to the protrusions 11 in the second sublayer 2. The plurality of protrusions 11 are arranged along the width direction of the packaging film. The plurality of protrusions 11 can be evenly distributed on the first sublayer 1 and the second sublayer 2. The strength of the first sublayer 1 and the second sublayer 2 can be improved by the protrusions 11. Before subsequent lamination, not only can the slippage between the front cover plate 4 and the first packaging film 5 and between the back cover plate 8 and the second packaging film 7 be effectively improved, but also the slippage between the first packaging film 5 and the battery cell 61 and between the battery cell 61 and the second packaging film 7 can be effectively improved. During lamination, the hidden cracking of the battery cell 61 can be effectively improved, thereby improving the component yield.

[0061] Compared with the prior art, the photovoltaic module 100 provided in this embodiment achieves at least the following beneficial effects:

[0062] The photovoltaic module 100 provided in this embodiment includes a front cover plate 4, a first packaging film 5, a battery string 6, a second packaging film 7 and a back cover plate 8 which are stacked; the battery string 6 includes at least two battery cells 61; the first packaging film 5 and the second packaging film 7 both include a first sublayer 1 and a second sublayer 2 connected to the first sublayer 1, the first sublayer 1 and the second sublayer 2 are made of different materials, and the first sublayer 1 is located on a side close to the battery cell 61; by providing a plurality of protrusions 11 on the first sublayer 1, the strength of the first sublayer 1 in the first packaging film 5 and the second packaging film 7 can be improved; Alternatively, at least two protrusions 11 are provided on the first sublayer 1 and the second sublayer 2. The protrusions 11 in the first sublayer 1 and the second sublayer 2 can improve the strength of the first sublayer 1 and the second sublayer 2, which can not only effectively improve the slippage between the front cover plate 4 and the first packaging film 5 and between the back cover plate 8 and the second packaging film 7, but also effectively improve the slippage between the first packaging film 5 and the battery cell 61 and between the battery cell 61 and the second packaging film 7; and during lamination, the hidden cracking phenomenon of the battery cell 61 can be effectively improved, thereby improving the component yield.

[0063] In an optional implementation, the first sublayer 1 is provided with an anti-slip pattern 3 on the side away from the second sublayer 2, and the anti-slip pattern 3 includes a first stripe 31 and a second stripe 32 connected to the first stripe 31, and the extension direction of the first stripe 31 intersects with the extension direction of the second stripe 32. On the basis of at least two protrusions 11 being provided on the first sublayer 1, or on the first sublayer 1 and the second sublayer 2, the risk of sideslipping of the battery cell 61 can be reduced by the mutual cooperation between the first stripe 31 and the second stripe 32.

[0064] Table 1 shows the yield and slip of the components in the comparative example and the embodiment

[0065] type Yield Slip Comparative Example 98.56％ 0~8mm Example 99.13％ 0~3mm

[0066] It should be noted that the comparative example can be a conventional film component, and the embodiment is a photovoltaic component in this application. Referring to Table 1, it can be seen that the slip amount of the photovoltaic component in this application and the conventional film component in the comparative example is greatly reduced, and the yield is improved.

[0067] In an alternative embodiment, Figure 6 yes Figure 5 A partial enlarged view of the middle A; combined Figure 5 and Figure 6 As shown, the cell 61 includes a semiconductor substrate 610, and the semiconductor substrate 610 includes at least two first fine grid lines 611 located on a first partition 610a, and the at least two first fine grid lines 611 are arranged along the length direction of the semiconductor substrate 610 and extend along the width direction of the semiconductor substrate 610;

[0068] At least part of the first thin gate lines 611 are respectively provided with welding spots 612 on both sides along the length direction of the semiconductor substrate 610 ; at least two welding spots 612 are arranged along the width direction of the semiconductor substrate 610 .

[0069] Specifically, the battery cell 61 includes a semiconductor substrate 610, and the semiconductor substrate 610 includes a plurality of first fine grid lines 611 located on the first partition 610a. The plurality of first fine grid lines 611 are parallel to each other, and may include positive fine grid lines (not marked in the figure) and negative fine grid lines (not marked in the figure). The positive fine grid lines and the negative fine grid lines are alternately arranged along the length direction of the semiconductor substrate 610. The positive fine grid lines and the negative fine grid lines may extend along the width direction of the semiconductor substrate 610. The positive fine grid lines and the negative fine grid lines may be designed to be uninterrupted. When subsequently connecting welding wires (not shown in the figure), the welding wires with the same polarity are electrically connected to the positive fine grid lines or the negative fine grid lines by coating insulating glue, such as the positive welding wire is electrically connected to the positive fine grid line, and the negative welding wire is electrically connected to the negative fine grid line, so as to prevent the positive fine grid lines and the negative fine grid lines between the battery cells 61 from short-circuiting.

[0070] Some of the first fine grid lines 611 are respectively provided with welding points 612 on both sides along the length direction of the semiconductor substrate 610; or, all of the first fine grid lines 611 are respectively provided with welding points 612 on both sides along the length direction of the semiconductor substrate 610, and there are multiple welding points 612, and the multiple welding points 612 are arranged along the width direction of the semiconductor substrate 610. It can be understood that along the length direction of the semiconductor substrate 610, the multiple welding points 612 are evenly distributed on both sides of the corresponding first fine grid lines 611. In this embodiment, the main grid line is designed with welding points 612. By increasing the number of welding points 612, the distance that the current passes through in the first fine grid line 611 is reduced, and the current carried by each main grid itself is reduced, so that the current collection is more uniform. At the same time, the light receiving area of ​​the battery cell 61 can be increased, which is beneficial to improving the battery efficiency.

[0071] It should be noted that: along the thickness direction of the semiconductor substrate 610 , the height of the solder joints 612 may be greater than the height of the first fine gate lines 611 , so that each column of solder joints 612 along the length direction of the semiconductor substrate 610 can be electrically connected to each solder wire 9 later.

[0072] The first fine gate line 611 may be a burn-through paste, which contacts the inner base of the semiconductor substrate 610 after burn-through. The solder joint 612 may be a main gate paste, which is a non-burn-through paste, and contacts the surface of the semiconductor substrate 610 .

[0073] Optionally, continue to refer to Figure 6 As shown, along the extending direction perpendicular to the first fine grid line 611 , the size of the welding point 612 ranges from 0.2 mm to 2.2 mm.

[0074] Specifically, on the one hand, when the size of the solder joint 612 is less than 0.2 mm along the extension direction perpendicular to the first fine grid line 611, it is easy to cause local overheating of the surface of the battery cell 61, causing the solder joint 612 to melt; on the other hand, when the size of the solder joint 612 is greater than 2.2 mm along the extension direction perpendicular to the first fine grid line 611, it can not only increase the surface shielding of the battery cell 61, reduce the power and photoelectric conversion efficiency, but also increase the amount of silver paste used; therefore, the size range of the solder joint 612 along the extension direction perpendicular to the first fine grid line 611 is designed to be 0.2 mm to 2.2 mm, which can not only prevent the local overheating of the surface of the battery cell 61 and avoid the melting of the solder joint 612, but also reduce the shielding of the surface of the battery cell 61, thereby improving the power and photoelectric conversion efficiency, while reducing the amount of silver paste used, thereby saving costs. Optionally, along the extension direction perpendicular to the first fine grid line 611, the size range of the solder joint 612 is 0.7 mm to 1.7 mm. Specifically, along the extension direction perpendicular to the first thin gate line 611, the size of the welding point 612 can be 0.2 mm, 0.4 mm, 0.7 mm, 0.9 mm, 1.1 mm, 1.4 mm, 1.7 mm, 1.9 mm or 2.2 mm.

[0075] Optionally, continue to refer to Figure 6 As shown, along the extension direction perpendicular to the first thin gate line 611, the shape of the welding point 612 can be any one or more of semicircular, arc, rectangular and diamond, and is designed according to actual conditions, and this embodiment does not make any specific limitation.

[0076] In an alternative embodiment, Figure 7 This is a structural schematic diagram of another battery cell provided by the utility model; Figure 8 yes Figure 7 A partial enlarged view of point B in the middle; combined Figure 7 and Figure 8 As shown, this embodiment further includes two second partitions 610b, and along the length direction of the semiconductor substrate 610, the first partition 610a is located between the two second partitions 610b;

[0077] The second partition 610b is provided with a connection structure 613 arranged along the width direction of the semiconductor substrate 610, each connection structure 613 includes a first anti-breaking grid line 613a and a second anti-breaking grid line 613b arranged relatively to each other, the first anti-breaking grid line 613a and the second anti-breaking grid line 613b extend along the length direction of the semiconductor substrate 610 respectively, the first anti-breaking grid line 613a and the second anti-breaking grid line 613b are connected to the welding point 612 near the side of the first fine grid line 611, at least one second fine grid line 613c is connected between the first anti-breaking grid line 613a and the second anti-breaking grid line 613b, and the second fine grid line 613c is electrically connected to the first fine grid line 611 through the connecting line 613d.

[0078] Specifically, combined Figure 7 and Figure 8 As shown, this embodiment also includes two second partitions 610b. Along the length direction of the semiconductor substrate 610, the first partition 610a is located between the two second partitions 610b. The area of ​​the first partition 610a can be larger than the area of ​​the second partition 610b, and the area of ​​the first partition 610a can also be larger than the sum of the areas of the two second partitions 610b.

[0079] Each second partition 610b is provided with a connection structure 613 arranged along the width direction of the semiconductor substrate 610, and there is a gap between two adjacent connection structures 613, and the positive projection of the gap along the length direction of the semiconductor substrate 610 can overlap with the positive projection of the welding point 612 along the length direction of the semiconductor substrate 610; each connection structure 613 includes a first anti-break grid line 613a and a second anti-break grid line 613b arranged opposite to each other, and the first anti-break grid line 613a and the second anti-break grid line 613b extend along the length direction of the semiconductor substrate 610 respectively, and the length of the first anti-break grid line 613a along the length direction of the semiconductor substrate 610 is equal to the length of the second anti-break grid line 613b along the length direction of the semiconductor substrate 610, and the first anti-break grid line 613a and the second anti-break grid line 613b along the length direction of the semiconductor substrate 610 are equal. The broken grid line 613a and the second anti-breaking grid line 613b are connected to the welding point 612 near the side of the first thin grid line 611, and the welding point 612 between the two adjacent connecting structures 613 and the two adjacent connecting structures 613 can form a harpoon structure. Specifically, a harpoon structure can be formed between the adjacent first anti-breaking grid lines 613a and the second anti-breaking grid lines 613b and the welding point 612. The second thin grid line 613c is connected between the first anti-breaking grid line 613a and the second anti-breaking grid line 613b, and the second thin grid line 613c is electrically connected to the first thin grid line 611 through the connecting line 613d. The above scheme can ensure the reliability of the battery cell 61 in subsequent welding, improve the welding quality, homogenize the stress distribution, and reduce the stress gradient.

[0080] In an alternative embodiment, Fig. 9 It is a cross-sectional schematic diagram of a photovoltaic module provided by the utility model; Fig. 9As shown, two adjacent battery cells 61 are electrically connected via a welding wire 9 , and the orthographic projection of the welding wire 9 on the plane where the front cover plate 4 is located is located within the orthographic projection of the raised portion 11 on the plane where the front cover plate 4 is located.

[0081] Specifically, continue to refer to Fig. 9 As shown, two adjacent battery cells 61 are electrically connected through the welding wire 9. It can be understood that the welding wire 9 is used to replace the main grid line of the existing structure. Since the main grid line is replaced by the welding wire 9, the silver paste consumption can be greatly reduced. By increasing the number of welding wires 9, the current transmission path on the surface of the battery cell 61 can be shortened, and the number of first fine grids can be greatly reduced from 100+ to 70+, further reducing the shading on the surface of the battery cell 61, reducing the silver paste consumption, and improving the conversion efficiency of the battery. The component power obtained by using the mainstream power of the main grid-free battery in this embodiment is 1.2W higher than that of the conventional BSL (ultra-thin battery).

[0082] Optionally, Fig.10 This is a schematic diagram of the structure of the welding wire and the battery cell provided by the utility model, referring to Fig.10 As shown, along the thickness direction of the semiconductor substrate 610, the cross-sectional shape of the welding wire 9 can be circular. The circular welding wire 9 has a smaller diameter than the flat welding strip. Since the welding wire 9 is used to replace the main grid line, the welding wire 9 with a smaller diameter can narrow the width of the main grid line in the existing structure, further reduce the surface obstruction of the battery cell 61, thereby improving the optical reflection effect, thereby improving and further improving the light utilization rate.

[0083] Table 2 shows the reflection, power and some electrical properties of the comparative examples and the examples.

[0084] Grouping Comparative Example Example Reflective effect Difference better Module power Almost no improvement +3～5w Pmax(W) 548.31 555.45 <![CDATA[V OC (V)]]> 50.71 50.7 <![CDATA[I SC (A)]]> 13.47 13.59 FF(%) 80.27％ 80.61％ Vpmax(V) 42.45 43.02 Ipmax(A) 12.92 12.91 <![CDATA[R s (Oh)]]> 0.33 0.32 <![CDATA[R sh (Oh)]]> 899.1 804.2

[0085] It should be noted that: (1) Pmax is the maximum power (under current irradiation), V OC is the open circuit voltage, I sc is the short-circuit current, FF is the fill factor, Vpmax is the maximum power voltage, Ipmax is the maximum operating current, R s is the series resistance, R sh is a parallel resistor; (2) the comparative example may be a flat welding strip, and the embodiment may be a round welding wire);

[0086] From the results in Table 2, it can be concluded that the reflective effect in the embodiment is better than that in the comparative example, and the component power can be increased by 3-5w. SC , FF and other data are higher than those of the comparative example, while in the embodiment V OC (V), Vpmax, Ipmax, R s , R shThe data are lower than the control ratio. Replacing the flat welding strip with round welding wire can improve the optical reflection effect, component current and power.

[0087] The length extension direction of the welding wire 9 is perpendicular to the length extension direction of the first fine grid line 611. Along the thickness extension direction of the semiconductor substrate 610, the position of each welding wire 9 corresponds to the position of each column of welding points 612. Specifically, along the thickness extension direction of the semiconductor substrate 610, each welding wire 9 can be located above each column of welding points 612. During the lamination operation, the raised portion 11 in the first sublayer 1 (or the first sublayer 1 and the second sublayer 2) corresponds to the position of the welding wire 9. The welding area can use silver paste that is conducive to welding to ensure welding reliability, optimize the size of the first fine grid line 611 in the welding area, increase the effective welding area between the welding wire 9 and the first fine grid line 611, and improve welding reliability. After lamination, the position of the raised portion 11 in the first sublayer 1 (or the first sublayer 1 and the second sublayer 2) is aligned with the position of the welding wire 9 and the welding point 612. The raised portion 11 in the first sublayer 1 (or the first sublayer 1 and the second sublayer 2) can be compatible with different versions of the same welding wire 9 spacing, and can also fix the welding wire 9 to improve slippage.

[0088] Optionally, the diameter of the welding wire 9 is in the range of 0.2 mm to 0.42 mm.

[0089] Specifically, continue to refer to Fig. 9 and Fig.10 As shown, if the diameter of the welding wire 9 is less than 0.2mm, the subsequent welding difficulty of the welding wire 9 and the welding spot 612 will increase, and the welding reliability will be reduced. If the diameter of the welding wire 9 is greater than 0.42mm, the optical reflection effect will be reduced, thereby reducing the component power and optical conversion efficiency. Therefore, the diameter of the welding wire 9 is designed to be 0.2mm~0.42mm, which not only reduces the welding difficulty of the welding wire 9 and the welding spot 612, but also increases the welding reliability, while improving the optical reflection effect, thereby improving the component power and optical conversion efficiency. Optionally, the diameter range of the welding wire 9 is 0.26mm~0.36mm. Specifically, the diameter of the welding wire 9 can be 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm or 0.42mm.

[0090] It can be seen from the above embodiments that the encapsulation film and photovoltaic module 100 provided by the utility model achieve at least the following beneficial effects:

[0091] The utility model provides an encapsulation film and a photovoltaic module, wherein the encapsulation film comprises a first sublayer and a second sublayer connected to the first sublayer, the first sublayer and the second sublayer are made of different materials, and the first sublayer is located below the second sublayer; at least two protrusions are provided on the first sublayer, and the strength of the first sublayer can be improved by the protrusions; or at least two protrusions are provided on the first sublayer and the second sublayer, and the at least two protrusions are arranged along the width direction of the encapsulation film, and the strength of the first sublayer and the second sublayer can be improved by the protrusions, which can not only effectively improve the hidden cracking phenomenon of the battery cells, thereby improving the module yield, but also prevent the front cover plate and / or the back cover plate from slipping with the battery cells.

[0092] The patent name of the case filed on the same day as the present application is "Encapsulation Film and Photovoltaic Module". The differences between the encapsulation film of the present application and the encapsulation film of the case filed on the same day are as follows: (1) The interface between the first sublayer 1 and the second sublayer 2 is a curved surface, so as to increase the contact area between the first sublayer 1 and the second sublayer 2, so that the first sublayer 1 and the second sublayer 2 are more firmly bonded; (2) On the basis of at least two raised portions 11 being provided on the first sublayer 1, or the first sublayer 1 and the second sublayer 2, anti-slip grooves 3 are further provided, and the anti-slip grooves 3 are located on the side of the first sublayer 1 away from the second sublayer 2, so as to reduce the risk of side slip between the encapsulation film and the solar cell before lamination; (3) When at least two raised portions 11 are provided on the first sublayer 1 and the second sublayer 2, since there is also a raised portion on the side of the second sublayer 2 away from the first sublayer, there is no need to design an anti-slip structure on the side of the second sublayer 2 away from the first sublayer 1; therefore, the invention points of the encapsulation film of the present application and the encapsulation film of the case filed on the same day are different.

[0093] The differences between the photovoltaic module of the present application and the photovoltaic module in the case filed on the same day are as follows: (1) Improvements have been made to the structure of the cell, and at least part of the first fine grid lines 611 are provided with welding points 612 on both sides along the length direction of the semiconductor substrate 610, such as the main grid lines are designed in a welding point manner; the semiconductor substrate is divided into a first partition and a second partition, and the grid lines of the first partition and the second partition are designed accordingly, which can ensure the reliability of the subsequent welding of the cell 61; (2) The use of welding wire instead of the main grid line is beneficial to significantly reduce the use of slurry, thereby reducing costs; (3) The shape and structure of the welding wire are improved, which is beneficial to reduce the shading area; therefore, the invention points of the photovoltaic module of the present application are different from those of the photovoltaic module in the case filed on the same day.

[0094] Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present invention. It should be understood by those skilled in the art that the above embodiments may be modified without departing from the scope and spirit of the present invention. The scope of the present invention is defined by the appended claims.

Claims

1. A packaging film, characterized in that: The method comprises a first sublayer and a second sublayer connected to the first sublayer, wherein the first sublayer and the second sublayer are made of different materials, and the first sublayer is located below the second sublayer; At least two protrusions are arranged on the first sub-layer, or on the first sub-layer and the second sub-layer, and at least two of the protrusions are arranged along the width direction of the packaging film.

2. The packaging film according to claim 1, characterized in that: A corrugated structure is formed between at least two of the raised portions.

3. The packaging film according to claim 1, characterized in that: The thickness ratio of the first sublayer to the second sublayer is in the range of 0.1-0.

4.

4. The packaging film according to claim 1, characterized in that: The first sublayer is provided with an anti-slip pattern on a side away from the second sublayer. The anti-slip pattern includes a first stripe and a second stripe connected to the first stripe. The extension direction of the first stripe intersects with the extension direction of the second stripe.

5. The packaging film according to claim 4, characterized in that: The number of the first stripes and the number of the second stripes are both multiple, and the multiple first stripes and the multiple second stripes form a tic-tac-toe pattern.

6. A photovoltaic module, characterized in that: It includes a front cover plate, a first packaging film, a battery string, a second packaging film and a back cover plate which are stacked; the battery string includes at least two battery cells; The first encapsulation film and the second encapsulation film both include a first sublayer and a second sublayer connected to the first sublayer, the first sublayer and the second sublayer are made of different materials, and the first sublayer is located close to the battery cell; At least two protrusions are disposed on the first sub-layer, or the first sub-layer and the second sub-layer, and the at least two protrusions are arranged along the width direction of the first packaging film and / or the second packaging film.

7. The photovoltaic module according to claim 6, characterized in that: The cell comprises a semiconductor substrate, the semiconductor substrate comprises at least two first fine grid lines located on a first partition, and the at least two first fine grid lines are arranged along a length direction of the semiconductor substrate and extend along a width direction of the semiconductor substrate; At least part of the first fine gate lines are respectively provided with welding spots on both sides along the length direction of the semiconductor substrate; and at least two welding spots are arranged along the width direction of the semiconductor substrate.

8. The photovoltaic module according to claim 7, characterized in that: Along the extending direction perpendicular to the first thin grid lines, the size of the welding points ranges from 0.2 mm to 2.2 mm.

9. The photovoltaic module according to claim 7, characterized in that: It also includes two second partitions, and along the length direction of the semiconductor substrate, the first partition is located between the two second partitions; The second partition is provided with a connection structure arranged along the width direction of the semiconductor substrate, each of the connection structures includes a first anti-breaking gate line and a second anti-breaking gate line arranged opposite to each other, the first anti-breaking gate line and the second anti-breaking gate line respectively extend along the length direction of the semiconductor substrate, the first anti-breaking gate line and the second anti-breaking gate line are connected to the welding point close to the side of the first fine gate line, at least one second fine gate line is connected between the first anti-breaking gate line and the second anti-breaking gate line, and the second fine gate line is electrically connected to the first fine gate line through a connecting line.

10. The photovoltaic module according to claim 7, characterized in that: Two adjacent battery cells are electrically connected via welding wires, and the orthographic projection of the welding wire on the plane where the front cover plate is located is located within the orthographic projection of the bulge on the plane where the front cover plate is located.

11. The photovoltaic module according to claim 10, characterized in that: The diameter of the welding wire ranges from 0.20 to 0.42 mm.

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