CN116230793A

CN116230793A - Photovoltaic module and preparation method thereof

Info

Publication number: CN116230793A
Application number: CN202310116607.5A
Authority: CN
Inventors: 郝国晖; 黄世亮; 郭志球; 刘立勤; 张池
Original assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Current assignee: Zhejiang Jinko Solar Co Ltd; Jinko Solar Co Ltd
Priority date: 2023-01-16
Filing date: 2023-01-16
Publication date: 2023-06-06

Abstract

The embodiment of the application relates to the technical field of photovoltaics, and provides a photovoltaic module and a preparation method thereof, wherein the photovoltaic module comprises: a plurality of battery pieces, wherein the surface of each battery piece is provided with a plurality of grid lines; the connecting parts are positioned on the surfaces of the battery pieces and are respectively connected with adjacent battery pieces, and the parts positioned on the grid lines are in contact connection with the adjacent parts of the grid lines; the packaging layer covers the surface of the battery piece and the surface of the connecting part, and the packaging layer comprises a first packaging layer and a second packaging layer which are sequentially distributed along the direction away from the battery piece, wherein the fluidity of the first packaging layer is smaller than that of the second packaging layer. The embodiment of the application is at least beneficial to improving the efficiency and the yield of the photovoltaic module.

Description

Photovoltaic module and preparation method thereof

Technical Field

The embodiment of the application relates to the technical field of photovoltaics, in particular to a photovoltaic module and a preparation method thereof.

Background

With the development of photovoltaic technology, in the manufacture of photovoltaic cells or photovoltaic modules, the realization of improvement of the efficiency of photovoltaic cells and the realization of improvement of the yield of photovoltaic cells have become a major problem of concern while saving the manufacturing cost.

The grid line is used as an important component of the solar cell and is used for collecting and leading out electrons generated by a photovoltaic effect, the welding strip is used for connecting the cell in the photovoltaic module, and the arrangement mode of the grid line and the welding strip, the welding quality of the welding strip and the grid line, the selection of the welding strip material and the grid line material, the welding mode of the welding strip and the grid line, the adhesive film above the welding strip and the like have certain influence on the photoelectric conversion efficiency of the cell, the efficiency of the photovoltaic module, the yield of the photovoltaic module and the service life of the photovoltaic module, and currently, the arrangement modes of the grid line, the welding strip and the adhesive film in the photovoltaic module are to be improved.

Disclosure of Invention

The embodiment of the application provides a photovoltaic module and a preparation method thereof, which are at least beneficial to improving the efficiency and yield of the photovoltaic module.

According to some embodiments of the present application, an aspect of embodiments of the present application provides a photovoltaic module, including: a plurality of battery pieces, each of which has a plurality of gate lines on a surface thereof; the connecting parts are positioned on the surfaces of the battery pieces and are respectively connected with adjacent battery pieces, and part of connecting parts positioned on the grid lines are in contact connection with adjacent part of grid lines; the packaging layer covers the surface of the battery piece and the surface of the connecting component, and the packaging layer comprises a first packaging layer and a second packaging layer which are sequentially arranged along the direction far away from the battery piece, wherein the mobility of the first packaging layer is smaller than that of the second packaging layer.

In some embodiments, the ratio of the ML value of the first encapsulation layer to the ML value of the second encapsulation layer is 1.5-8.5.

In some embodiments, the first encapsulation layer has an ML value of 0.4 dNm to 0.85 dNm, and/or the second encapsulation layer has an ML value of 0.1 dNm to 0.3 dNm.

In some embodiments, further comprising: and the glue point is positioned between part of the battery pieces and the connecting part, and the glue point is positioned on the surface of the battery piece except the grid line.

In some embodiments, the first encapsulation layer and the second encapsulation layer are an integrally formed structure.

In some embodiments, the ratio of the thickness of the first encapsulation layer to the maximum thickness of the connection member in the direction in which the battery sheet is directed toward the encapsulation layer is 0.4 to 1.

In some embodiments, the ratio of the thickness of the first encapsulation layer to the thickness of the second encapsulation layer along the direction of the battery sheet toward the encapsulation layer is 0.3 to 1.5.

In some embodiments, the material of the first encapsulation layer is the same as the material of the second encapsulation layer.

According to some embodiments of the present application, another aspect of embodiments of the present application further provides a method for preparing a photovoltaic module, including: providing a plurality of battery pieces, wherein the surface of each battery piece is provided with a plurality of grid lines; a connecting component is arranged on the surface of the battery piece; the surface of the battery piece is provided with a packaging layer, the packaging layer is positioned at one side of the connecting part, which is far away from the battery piece, and the packaging layer comprises a first packaging layer and a second packaging layer which are sequentially arranged along the direction far away from the battery piece; laminating the battery piece, the connecting part and the packaging layer at a preset temperature to enable part of the connecting part above the grid line to be in contact connection with the adjacent part of the grid line and enable the battery piece to be fixed with the packaging layer; the fluidity of the first packaging layer at the preset temperature is smaller than that of the second packaging layer at the preset temperature.

In some embodiments, providing the connection component further comprises: and forming glue points, wherein the glue points are positioned between part of the battery pieces and the connecting part, and the glue points are positioned on the surfaces of the battery pieces except the grid lines.

The technical scheme provided by the embodiment of the application has at least the following advantages: the grid line can be a thin grid on the surface of the battery piece, the connecting component can be a welding strip which is arranged on the surface of the battery piece instead of the main grid and is used for connecting adjacent battery pieces, and the connecting component is used for replacing the main grid, so that the thicker main grid is avoided, and the cost of the photovoltaic module is reduced; on the other hand, the main grid is prevented from excessively shielding the surface of the battery piece, so that the photoelectric conversion efficiency of the battery piece is improved, and the efficiency of the photovoltaic module is improved. The packaging layer is used for covering the surfaces of the battery piece and the connecting component and protecting the battery piece, the packaging layer comprises a first packaging layer adjacent to the surface of the battery piece and adjacent to the connecting component, and a second packaging layer far away from the battery piece, and the fluidity of the first packaging layer is smaller than that of the second packaging layer, wherein the fluidity of the first packaging layer and the fluidity of the second packaging layer are both the fluidity at the lamination temperature, namely the photovoltaic module is the photovoltaic module in the lamination process. The lamination process refers to: and (3) paving a connecting part on the surface of the battery piece, covering an encapsulation layer on the connecting part and the surface of the battery piece exposed by the connecting part, and then laminating the battery piece, the connecting part and the encapsulation layer, wherein the lamination process has a certain lamination temperature, and the connecting part and a grid line positioned below the connecting part form an alloy at the lamination temperature so as to form contact connection. Under normal conditions, when the packaging layer is in a scorching stage at the lamination temperature, the packaging layer is in a state with fluidity, in order to avoid poor contact between the connecting component and the grid line caused by the fact that the packaging layer in the scorching stage flows into the space between the connecting component and the grid line before the connecting component and the grid line form an alloy, the first packaging layer adjacent to the connecting component and the battery piece is set in a state with smaller fluidity, so that the first packaging layer can be prevented from flowing between the connecting component and the grid line, and further poor contact between the connecting component and the grid line is avoided, and the efficiency and the yield of the photovoltaic module are improved. In addition, the first packaging layer is utilized to isolate the second packaging layer with relatively large mobility, the second packaging layer with large mobility is utilized to ensure that the whole packaging layer still has large crosslinking degree, the packaging layer is ensured to well protect the battery, the bonding strength of the packaging layer and the cover plate is improved, and the service life of the photovoltaic module is prolonged.

Drawings

One or more embodiments are illustrated by way of example and not limitation in the figures of the accompanying drawings, which are not to be construed as limiting the embodiments unless specifically indicated otherwise; in order to more clearly illustrate the embodiments of the present application or the technical solutions in the conventional technology, the drawings that are required to be used in the embodiments will be briefly described below, and it is apparent that the drawings in the following description are only some embodiments of the present application, and other drawings may be obtained according to these drawings without inventive effort for a person of ordinary skill in the art.

Fig. 1 is a schematic cross-sectional structure of a photovoltaic module according to an embodiment of the present disclosure;

fig. 2 is a schematic structural diagram of a grid line and a connection component on a surface of a battery piece according to an embodiment of the present disclosure;

FIG. 3 is a schematic view of a curing curve according to an embodiment of the present disclosure;

fig. 4 is a schematic partial cross-sectional structure of a photovoltaic module according to an embodiment of the present disclosure;

fig. 5 is a schematic structural diagram corresponding to a step of providing a battery sheet in a method for manufacturing a photovoltaic module according to an embodiment of the present disclosure;

Fig. 6 is a schematic structural diagram corresponding to a step of dispensing in a preparation method of a photovoltaic module according to an embodiment of the present application;

fig. 7 is a schematic structural diagram corresponding to a step of fixing a connecting component by using glue points in a method for manufacturing a photovoltaic module according to an embodiment of the present disclosure;

fig. 8 is a schematic structural diagram corresponding to a step of disposing an encapsulation layer in a method for manufacturing a photovoltaic module according to an embodiment of the present application;

fig. 9 is a schematic structural diagram of a photovoltaic module after lamination treatment in the method for manufacturing a photovoltaic module according to an embodiment of the present application.

Detailed Description

As known from the background art, the arrangement mode of the grid line, the solder strip and the adhesive film in the photovoltaic module needs to be improved.

Analysis shows that sunlight enters the battery from the surface of the battery piece, the grid line on the surface of the battery piece can shade the battery piece, and the light energy irradiated on the metal electrode cannot be converted into electric energy, so that the finer and better the grid line is generally expected from the view of shading the illumination; and the grid line is used for conducting current, and from the aspect of resistivity analysis, the thinner the grid line is, the smaller the conductive cross-sectional area is, and the larger the resistance loss is. Therefore, the core of the gate line design is to balance between light shielding and conductivity. In addition, in general, the paste for manufacturing the grid lines has a main component of expensive precious metal silver, and in the process of connecting the battery pieces in series into the assembly, the main grid of one battery piece needs to be welded with the main grid of the adjacent battery piece through the welding strip, so that a thicker main grid is usually required to be formed to ensure the connection between the welding strip and the main grid, and in sum, the main grid with higher material cost and thicker material cost causes higher assembly preparation cost. If the main grid is replaced by the welding strip with lower material cost, more thinner welding strips are directly connected with the thin grid of the battery, so that the manufacturing cost of the grid line and the welding strip is reduced, and the photoelectric conversion efficiency of the solar battery is improved.

However, the conventional welding strip and the grid line are required to be connected by welding to enable the welding strip and the grid line to be alloyed, in general, the conventional welding strip comprises a tin welding layer, the melting point of the tin welding layer in the welding strip is 183 ℃, and in the actual welding process, the welding temperature is higher than the melting point of the welding flux by more than 20 ℃, so that the welding strip and the grid line are required to be alloyed, the higher welding temperature leads to larger buckling deformation of the battery piece in the welding process, and further leads to larger hidden cracking risk and higher breakage rate of the battery piece after welding, and the assembly repair rate is increased and the yield is reduced. Therefore, in order to reduce welding damage, a low temperature solder strip may be employed. The low-temperature welding belt is connected with the grid line in the laminating process, but in the laminating process, the adhesive film above the welding belt is converted into a state with fluidity due to the temperature rise, and the adhesive film with fluidity easily flows between the welding belt and the grid line before the welding belt and the grid line form an alloy, so that poor contact between the welding belt and the grid line is caused, and the efficiency and the yield of the photovoltaic module are further affected.

In order to solve the problems, the implementation of the application provides a photovoltaic module and a preparation method thereof, wherein in the photovoltaic module, grid lines can be thin grids on the surfaces of battery pieces, connecting parts can be welding strips which are arranged on the surfaces of the battery pieces instead of main grids and are used for connecting adjacent battery pieces, and the main grids are replaced by the connecting parts, so that the thicker main grids are avoided, and the cost of the photovoltaic module is reduced; on the other hand, the main grid is prevented from excessively shielding the surface of the battery piece, so that the photoelectric conversion efficiency of the battery piece is improved, and the efficiency of the photovoltaic module is improved. The packaging layer comprises a first packaging layer adjacent to the surface of the battery piece and the connecting part, and a second packaging layer far away from the battery piece, wherein the flowability of the first packaging layer is smaller than that of the second packaging layer, the flowability of the first packaging layer and the flowability of the second packaging layer are both the flowability at the lamination temperature, namely, the photovoltaic module is the photovoltaic module in the lamination process, the connecting part is paved on the surface of the battery piece, after the connecting part and the surface of the battery piece exposed by the connecting part are covered by the packaging layer, the battery piece, the connecting part and the packaging layer are laminated, the lamination process has a certain lamination temperature, the connecting part and the grid line positioned below the connecting part are formed into an alloy at the lamination temperature, and the first packaging layer adjacent to the connecting part and the battery piece is set into a state with smaller flowability at the lamination temperature, so that the first packaging layer is prevented from flowing between the connecting part and the grid line, and poor contact between the connecting part and the grid line is caused, and the efficiency and the yield of the photovoltaic module are improved. In addition, the first packaging layer is utilized to isolate the second packaging layer with relatively larger mobility, the second packaging layer with larger mobility is utilized to ensure that the whole packaging layer has larger crosslinking degree, and then the packaging layer is utilized to perform good packaging protection on the battery, and the bonding strength of the packaging layer and the cover plate is improved, so that the service life of the photovoltaic module is prolonged.

Embodiments of the present application will be described in detail below with reference to the accompanying drawings. However, as will be appreciated by those of ordinary skill in the art, in the various embodiments of the present application, numerous technical details have been set forth in order to provide a better understanding of the present application. However, the technical solutions claimed in the present application can be implemented without these technical details and with various changes and modifications based on the following embodiments.

Fig. 1 is a schematic cross-sectional structure of a photovoltaic module according to an embodiment of the present disclosure; fig. 2 is a schematic structural diagram of a grid line and a connection component on a surface of a battery piece according to an embodiment of the present application.

Referring to fig. 1 and 2, the photovoltaic module includes: a plurality of battery cells 100, each of the battery cells 100 having a surface with a plurality of gate lines 110; and connecting members 120, wherein the connecting members 120 are positioned on the surfaces of the battery cells 100, and the connecting members 120 are respectively connected with adjacent battery cells 100, and a portion of the connecting members 120 positioned on the grid lines 110 are in contact connection with adjacent portions of the grid lines 110.

The cell 100 is configured to absorb photons of incident light and generate electron-hole pairs, which are separated by a built-in electric field in the cell 100, and generate an electric potential across the PN junction, thereby converting light energy into electrical energy. In some embodiments, one surface of the battery sheet 100 serves as a light receiving surface for absorbing incident light. In other embodiments, both surfaces of the battery sheet 100 serve as light receiving surfaces for absorbing incident light. In some embodiments, the cell sheet 100 may be a crystalline silicon solar cell, for example, a monocrystalline silicon solar cell or a polycrystalline silicon solar cell. It is understood that in some embodiments, the number of the battery cells 100 in one photovoltaic module may be one or more, and when the number of the battery cells 100 is plural, the plurality of battery strings may be formed by electrically connecting in the form of a whole sheet or a plurality of sheets (for example, a plurality of sheets such as 1/2 equal sheet, 1/3 equal sheet, and 1/4 equal sheet), and the plurality of battery strings may be electrically connected in series and/or parallel.

The battery plate 100 may include, but is not limited to, any of PERC cells (Passivated Emitter and Rear Cell, passivated emitter and backside 102 cells), PERT cells (Passivated Emitter and Rear Totally-diffused cell, passivated emitter back surface full diffusion cell), TOPCon cells (Tunnel Oxide Passivated Contact, tunnel oxide passivation contact cell), HIT/HJT cells (Heterojunction Technology, heterojunction cell).

The battery sheet 100 may include a substrate, which may be a silicon substrate. In some embodiments, the battery sheet 100 has opposite front and

back sides

101 and 102, and the front and

back sides

101 and 102 may each be printed with a metal paste to form a grid line 110 having a specific pattern.

In some embodiments, the plurality of battery cells 100 in the photovoltaic module are arranged at intervals, and the plurality of battery cells 100 are arranged in parallel, and the connection member 120 forms an electrical connection between two battery cells 100 by respectively connecting opposite surfaces of two adjacent battery cells 100.

In some embodiments, the connection member 120 may be a solder ribbon, and the connection member 120 may have any one of a circular shape, a rectangular shape, a trapezoid shape, and a triangular shape in a cross-section perpendicular to the extension direction of the connection member 120.

In some embodiments, the grid line 110 may be a thin grid on the surface of the battery plate 100, where the thin grid is used to collect and export electrons generated by the photovoltaic effect. The connecting component 120 can replace a main grid to be arranged on the surface of the battery piece 100 and is used for connecting welding strips of adjacent battery pieces 100, and the connecting component 120 is used for replacing the main grid, so that the thicker main grid is avoided, and the cost of the photovoltaic module is reduced; on the other hand, the main grid is prevented from excessively shielding the surface of the battery piece 100, so that the photoelectric conversion efficiency of the battery piece 100 is improved, and the efficiency of the photovoltaic module is improved.

In some embodiments, referring to fig. 2, the gate lines 110 may be thin grids on the surface of the battery cell 100, the connection members 120 may be solder strips disposed on the surface of the battery cell 100 instead of the main grids and used for connecting adjacent battery cells 100, the plurality of gate lines 110 extend along a first direction X on the surface of the battery cell and are arranged at intervals along a second direction Y, and the plurality of connection members 120 extend along the second direction Y on the surface of the battery cell and are arranged at intervals along the first direction X, wherein the first direction X intersects the second direction Y.

In some embodiments, the gate line 110 may also be a main gate and a thin gate. The fine grid is used for guiding current, and the main grid is used for collecting the current on the fine grid so as to conduct confluence. The connection member 120 is a solder strip connected to the main grid.

It should be noted that, the connecting component 120 in the embodiment of the present application is a low-temperature welding strip, and the low-temperature welding strip is connected with the grid line 110 in the lamination process, so that the welding temperature caused by the high-temperature welding strip is avoided, and further the damage to the battery piece 100 caused by the too high welding temperature is avoided, which is beneficial to reducing the repair rate of the photovoltaic module and improving the yield of the photovoltaic module.

In some embodiments, the connecting member 120 is a tin-coated metal solder strip, and the tin layer has a melting temperature of no higher than 150 ℃, typically 130 ℃ to 150 ℃, which is advantageous for adapting to the lamination temperature of the photovoltaic module.

Referring to fig. 1, the photovoltaic module further includes an encapsulation layer 130, the encapsulation layer 130 covers the surface of the battery sheet 100 and the surface of the connection member 120, and the encapsulation layer 130 includes a first encapsulation layer 131 and a second encapsulation layer 132 sequentially arranged along a direction away from the battery sheet 100, wherein flowability of the first encapsulation layer 131 is less than flowability of the second encapsulation layer 132. The packaging layer is used for packaging and protecting the battery piece, and can be an adhesive film.

In some embodiments, the encapsulation layer 130 is disposed on the front surface 101 and the back surface 102 of the battery sheet 100, and covers the connection member 120 on the surface of the battery sheet 100, for encapsulating the battery sheet 100, and may bond the battery sheet 100 with a cover plate (not shown).

It should be noted that, the fluidity of the first encapsulation layer 131 and the fluidity of the second encapsulation layer 132 are both the fluidity at the lamination temperature, that is, the photovoltaic module is a photovoltaic module in the lamination process, the lamination process refers to the process of laying the connection component 120 on the surface of the battery piece 100, and laminating the battery piece 100, the connection component 120 and the encapsulation layer 130 after covering the encapsulation layer 130 on the surface of the connection component 120 and the surface of the battery piece 100 exposed by the connection component 120, the lamination process has a certain lamination temperature, at the lamination temperature, the connection component 120 and the grid line 110 located below the connection component 120 form an alloy, so as to form contact connection, and at the lamination temperature, the encapsulation layer is in a state with fluidity when the encapsulation layer is in a scorching stage, the first encapsulation layer 131 adjacent to the connection component 120 and the battery piece 100 is set in a state with smaller fluidity, so that poor contact between the connection component 120 and the grid line 110 is avoided, thereby being beneficial to improving the efficiency and yield of the photovoltaic module. In addition, the first packaging layer 131 is utilized to isolate the second packaging layer 132 with relatively large mobility, and the second packaging layer 132 with relatively large mobility is utilized to ensure that the packaging layer 130 has large crosslinking degree, so that the packaging layer 130 is ensured to perform good packaging protection on the battery, and the bonding strength of the packaging layer 130 and the cover plate is improved, thereby being beneficial to prolonging the service life of the photovoltaic module.

The fluidity of the first encapsulation layer 131 may be represented by the ML value of the first encapsulation layer 131, the fluidity of the second encapsulation layer 132 may be represented by the ML value of the second encapsulation layer 132, the ML value is the lowest torque in the vulcanization curve of the adhesive film, the lower the ML value, the greater the fluidity of the adhesive film before the crosslinking reaction occurs in the lamination process; the higher the ML value, the less fluid the film has before the crosslinking reaction occurs during lamination.

It should be noted that, the vulcanization curve is used for representing the vulcanization performance of the adhesive film, the vulcanization performance is the performance of the adhesive film in the vulcanization process, the adhesive film can undergo a vulcanization reaction in the vulcanization process, and the vulcanization reaction (crosslinking reaction) refers to: the molecular chain of the adhesive film is crosslinked under the action of chemical factors or physical factors to become a space network structure. The linear macromolecules of the unvulcanized adhesive film are curled and in a free movement state, when the linear macromolecules are subjected to the action of external force, the linear macromolecules are easy to displace, namely larger plastic flow exists, and in the vulcanized adhesive film, the soft linear macromolecules are changed into a space reticular structure through crosslinking, so that the relative movement of the linear macromolecules is limited to a certain extent, the linear macromolecules are not easy to displace greatly under the action of external force, higher stress and strength are generated, and the physical and mechanical properties and chemical properties are improved through vulcanization.

Under the normal condition, the change of the vulcanization performance of the adhesive film in the vulcanization process can be measured by adopting a vulcanization tester, and the principle of the vulcanization tester is as follows: and (3) performing compression molding on the adhesive film positioned in the mold cavity so as to enable the adhesive film to continuously bear constant, small-amplitude and low-frequency sinusoidal shear deformation, measuring the shear stress by a force transducer of a vulcanization tester, and representing the shear stress by taking torque as a unit, wherein a recorded shear stress-time curve is a vulcanization curve.

FIG. 3 is a schematic view of a curing curve according to an embodiment of the present application. Referring to fig. 3, the curing process of the adhesive film can be divided into four stages: a scorch stage, a hot vulcanization stage, a flat vulcanization stage and a oversulfur stage. The scorch stage corresponds to the induction period in the vulcanization reaction, during which time crosslinking has not yet started, the film has fluidity, and the film generates crosslinkable free radicals. The hot vulcanization stage is a vulcanization reaction (crosslinking reaction) stage, the film molecules gradually form a net structure, and the elasticity and strength of the film are rapidly increased. In the flat vulcanization stage, the adhesive film has reached a proper degree of crosslinking, and in this period, each physical and mechanical property of the adhesive film reaches or approaches the optimal point, or the optimal comprehensive balance is obtained. In the stage of the over-sulfur, the crosslinking bonds in the adhesive film are rearranged, and the crosslinking bonds and molecular chains in the adhesive film are subjected to thermal cracking reaction, so that the performance of the adhesive film is reduced.

Referring to fig. 3, the lowest torque ML represents the minimum shear stress value before the crosslinking reaction of the adhesive film starts, i.e., the maximum value of the flowability of the adhesive film before the flat vulcanization stage in the vulcanization process.

In some embodiments, the first encapsulation layer 131 before lamination is a pre-crosslinked adhesive film, and the second encapsulation layer 132 before lamination is a non-pre-crosslinked adhesive film, which differs from the pre-crosslinked adhesive film in that: before lamination, whether crosslinking reaction occurs between molecules in the adhesive film material or not. Crosslinking reaction refers to the bonding of 2 or more molecules (typically linear molecules) to each other to crosslink into a more stable molecule (bulk molecule) of network structure. In general, in the lamination process, after a certain lamination time at a certain lamination temperature, the adhesive film is in a state with high fluidity (scorch stage), and the crosslinking agent in the adhesive film is decomposed to generate free radicals. Along with the extension of time, the free radical initiates the combination of long chain molecules in the adhesive film, so that the adhesive film, the battery piece and the cover plate are adhered and fixed together. Before lamination, some molecules inside the pre-crosslinked film have already undergone crosslinking reaction, so that the fluidity of the pre-crosslinked film at the scorch stage is smaller than that of the non-pre-crosslinked film at the scorch stage.

In some embodiments, the first encapsulation layer 131 and/or the second encapsulation layer 132 may be POE (ethylene octene copolymer) adhesive films, where the POE adhesive films are composed of saturated aliphatic chains, and have the characteristics of good ultraviolet aging resistance, excellent heat resistance, low temperature resistance, wide use temperature range, good light transmittance, excellent electrical insulation performance, high cost performance, easy processing, and the like. In other embodiments, the first packaging layer 131 and/or the second packaging layer 132 may also be an EVA film, which is a relatively common adhesive film, and the EVA film has an ethylene-vinyl acetate copolymer (EVA) as a main component, and may further include a small amount of cross-linking agent, a co-cross-linking agent, an anti-aging agent, and other functional additives.

In some embodiments, the material of the first encapsulation layer 131 and the material of the second encapsulation layer 132 are the same. The same material is adopted as the first packaging layer 131 and the second packaging layer 132, which is favorable for ensuring that the molecules of the first packaging layer 131 and the molecules of the second packaging layer 132 have higher bonding strength, and further is favorable for improving the bonding strength between the laminated first packaging layer 131 and second packaging layer 132.

In some embodiments, the first encapsulation layer 131 and the second encapsulation layer 132 are an integrally molded structure. Compared with the lamination of the split first packaging layer 131 and the second packaging layer 132, the integrated first packaging layer 131 and the second packaging layer 132 are directly adopted as the packaging layer 130, so that the high adhesive fixing strength between the first packaging layer 131 and the second packaging layer 132 is guaranteed, and the structural stability of the photovoltaic module is improved.

In some embodiments, the material of the first encapsulation layer 131 and the material of the second encapsulation layer 132 are the same, and the first encapsulation layer 131 and the second encapsulation layer 132 are an integrally formed structure. In some embodiments, the encapsulation layer 130 may be formed by: the initial packaging layer is obtained, the initial packaging layer can be a non-pre-crosslinked adhesive film, and comprises a first part and a second part which are stacked, and the initial packaging layer is pre-crosslinked from one side, far away from the second part, of the first part, so that partial molecules in the initial packaging layer of the first part undergo a crosslinking reaction, and further a pre-crosslinked first packaging layer 131 with smaller fluidity is formed, the initial packaging layer of the second part is still a non-pre-crosslinked adhesive film, and the initial packaging layer of the second part is used as a second packaging layer 132 with larger fluidity, so that the obtaining difficulty of the packaging layer 130 is reduced. Wherein, the pre-crosslinking treatment can be electron beam irradiation or ultraviolet irradiation and other crosslinking treatments.

In some embodiments, the encapsulation layer 130 may be formed by: the method comprises the steps of obtaining a split type initial first packaging layer and an initial second packaging layer, wherein the initial first packaging layer and the initial second packaging layer are non-pre-crosslinked adhesive films, and pre-crosslinking treatment is carried out on the initial first packaging layer so that partial molecules in the initial first packaging layer undergo a crosslinking reaction to form a pre-crosslinked first packaging layer 131 with smaller fluidity, and the initial second packaging layer serves as a non-pre-crosslinked second packaging layer 132 with larger fluidity. The split first encapsulation layer 131 and the second encapsulation layer 132 are fixed together to form the encapsulation layer 130. Wherein, the pre-crosslinking treatment can be electron beam irradiation or ultraviolet irradiation and other crosslinking treatments.

In some embodiments, the ratio of the ML value of the first encapsulation layer to the ML value of the second encapsulation layer 132 is 1.5-8.5. If the ML value of the first encapsulation layer 131 is defined as ML1 and the ML value of the second encapsulation layer 132 is defined as ML2, the ratio of ML1 to ML2 is 1.5-8.5, for example, it may be: 1.5, 2, 4, 7 or 8.5. When the ratio of ML1 to ML2 is too small, the first encapsulation layer 131 is in a state of high fluidity, and thus the first encapsulation layer 131 in the scorching stage flows between the gate line 110 and the connection member 120, which are not alloyed, and the gate line 110 and the connection member 120 are in poor contact. Too large ratio of ML1 to ML2 may result in too small fluidity of the first encapsulation layer 131, that is, the molecular proportion of the first encapsulation layer 131 that has undergone the crosslinking reaction is too large before lamination, resulting in poor adhesion fixing ability of the first encapsulation layer 131 in the laminated photovoltaic module, so that the separation risk exists between the cell 100 and the first encapsulation layer 131 in the photovoltaic module. Therefore, the ratio of ML1 to ML2 is set to 1.5-8.5, which is not only beneficial to avoiding poor contact between the gate line 110 and the connection component 120, but also beneficial to ensuring that the first encapsulation layer 131 has higher adhesive strength.

In some embodiments, the ML value of the first encapsulation layer 131 is 0.4dN m to 0.85dN m, for example, may be 0.42dN m, 0.45dN m, 0.5dN m, 0.75dN m, or 0.8dN m, etc. If the ML value of the first encapsulation layer 131 is too small, the mobility of the first encapsulation layer 131 is too large, which may cause the first encapsulation layer 131 in the scorching stage to flow between the gate line 110 and the connection member 120, which are not alloyed, and cause poor contact between the gate line 110 and the connection member 120. If the ML value of the first encapsulation layer 131 is too large, the fluidity of the first encapsulation layer 131 is too small, that is, the molecular proportion of the first encapsulation layer 131, in which the crosslinking reaction has occurred, is too large before lamination, which may result in poor adhesion fixing ability of the first encapsulation layer 131 in the laminated photovoltaic module. Therefore, the ML value of the first encapsulation layer 131 is set to 0.4dn·m to 0.85dn·m, so that the fluidity of the first encapsulation layer 131 can be ensured to be within a reasonable range, which is beneficial to avoiding poor contact between the gate line 110 and the connection component 120, and also beneficial to ensuring that the first encapsulation layer 131 has higher adhesive strength.

In some embodiments, the ML value of the second encapsulation layer 132 is 0.1 dNm to 0.3 dNm, for example, may be 0.12 dNm, 0.15 dNm, 0.2 dNm, 0.25 dNm, or 0.3 dNm, etc. Too little fluidity of the second encapsulant layer 132 may result in too poor adhesive fixing ability of the second encapsulant layer 132 in the laminated photovoltaic module. Therefore, the ML value of the second encapsulation layer 132 is set to 0.1dn·m to 0.3dn·m, which is beneficial to ensure that the second encapsulation layer 132 has higher adhesive strength.

If the ML value of the first package layer is defined as ML1 and the ML value of the second package layer is defined as ML2, the influence of the ML value of the first package layer and the ML value of the second package layer on the connection state of the gate line and the connection member after lamination in the following table is referred to.

The data sources in the above table may be as follows: sampling the connection points of the connecting components and the grid lines, which are positioned in the same area, on the battery pieces of the comparative examples, wherein the total number of samples on each battery piece can be 50, counting the number of samples, which are in contact connection, of the connecting grid lines and the connecting components on the battery pieces, so as to obtain the percentage of the number of the samples, which are in contact connection, of the connecting components and the grid lines of the comparative examples, to obtain the percentage of the number of the samples, which are in contact connection, of the connecting components and the grid lines of the comparative examples.

Referring to the above table, when the value of the ML value (ML 2) of the second encapsulation layer is constant, the larger the ML value (ML 1) of the first encapsulation layer, the higher the percentage of the number of samples of the connection member in contact with the gate line to the total number of samples, that is, the lower the proportion of the poor contact of the connection member with the gate line (refer to comparative examples 1 to 2 and examples 1 to 3, or refer to comparative examples 3 to 4 and examples 4 to 6). When the ML value (ML 1) of the first encapsulation layer is 0.4dn·m or more, the number of samples of the connection member in contact connection with the grid line is more than 95% of the total number of samples, i.e., the photovoltaic module is a good product (reference examples 1 to 6). When the number of samples of the connection member in contact connection with the grid line is less than 95% of the total number of samples, the photovoltaic module is a defective product (refer to comparative examples 1 to 4). Therefore, the ML value of the first packaging layer is set to be more than 0.4 dN.m, which is beneficial to improving the yield and efficiency of the photovoltaic module.

With continued reference to the above table, when the ML value (ML 1) of the first encapsulation layer is greater than or equal to 0.4dn·m, the change of the ML value (ML 2) of the second encapsulation layer cannot affect the connection state of the gate line and the connection member (refer to embodiment 1 and embodiment 4, or embodiment 2 and embodiment 5, or embodiment 3 and embodiment 6), i.e., the first encapsulation layer having poor flow realizes effective isolation blocking for the second encapsulation layer.

Fig. 4 is a schematic partial cross-sectional structure of a photovoltaic module according to an embodiment of the present application.

In some embodiments, referring to fig. 4, the ratio of the thickness L2 of the first encapsulation layer 131 to the maximum thickness L1 of the connection member 120 in the direction in which the battery sheet 100 is directed to the encapsulation layer 130, i.e., in the Z-direction shown in fig. 4, is 0.4 to 1. For example, it may be 0.4, 0.5, 0.6, 0.7, 0.9, or the like. If the ratio of the thickness L2 of the first encapsulation layer 131 to the maximum thickness L1 of the connection member 120 is too large, the thickness L2 of the first encapsulation layer 131 may be too large, and the light absorption of the battery chip 100 may be affected by the too large thickness of the first encapsulation layer 131. Too small a ratio of the thickness L2 of the first encapsulation layer 131 to the maximum thickness L1 of the connection member 120 may result in too small a thickness L2 of the first encapsulation layer 131, which may result in the first encapsulation layer 131 failing to perform good blocking on the second encapsulation layer 132 during the scorching stage of the encapsulation layer in the lamination process, so that the second encapsulation layer 132 flows between the gate line 110 and the connection member 120. Therefore, the ratio of the thickness L2 of the first encapsulation layer 131 to the maximum thickness L1 of the connection member 120 is set to 0.4-1, which is beneficial to avoiding the excessively thick first encapsulation layer 131 from shielding the illumination, i.e. to ensuring that the battery chip 100 has a higher utilization rate of the illumination; on the other hand, the first encapsulation layer 131 is beneficial to ensure that the second encapsulation layer 132 is effectively blocked, so that good contact between the gate line 110 and the connection component 120 is beneficial to ensure.

In some embodiments, referring to fig. 4, the ratio of the thickness L2 of the first encapsulation layer 131 to the thickness L3 of the second encapsulation layer 132 in the direction in which the battery sheet 100 is directed toward the encapsulation layer 130 is 0.3 to 1.5. For example, it may be 0.4, 0.5, 0.6, 0.7, 1.2, or the like. In the case where the thickness L2 of the first encapsulation layer 131 is fixed, if the ratio of the thickness L2 of the first encapsulation layer 131 to the thickness L3 of the second encapsulation layer 132 is too large, the thickness L3 of the second encapsulation layer 132 is too small, and the second encapsulation layer 132 with too small thickness cannot perform good encapsulation protection on the battery sheet 100 due to the high adhesive strength of the laminated second encapsulation layer 132, which may cause the separation of the cover plate from the battery sheet 100. Moreover, the second packaging layer 132 with too small a thickness may cause the overall thickness of the packaging layer 130 to be too small, which may cause moisture to enter the battery cell 100 and cause the battery cell 100 to fail. If the ratio of the thickness L2 of the first encapsulation layer 131 to the thickness L3 of the second encapsulation layer 132 is too small, the thickness L3 of the second encapsulation layer 132 may be too large, and the light absorption of the battery sheet 100 may be affected by the second encapsulation layer 132 having too large thickness. In addition, the second encapsulation layer 132 having an excessive thickness may cause an increase in manufacturing cost of the photovoltaic module. Therefore, the ratio of the thickness L2 of the first encapsulation layer 131 to the thickness L3 of the second encapsulation layer 132 is set to 0.3-1.5, which is favorable for ensuring good encapsulation protection of the second encapsulation layer 132 on the battery piece 100, enhancing the utilization rate of the battery piece 100 on illumination, and ensuring reasonable material consumption for preparing the second encapsulation layer 132, thereby being favorable for realizing light weight of the photovoltaic module and reducing the preparation cost of the photovoltaic module.

Note that, in the embodiment of the present application, the maximum thickness L1 of the connection member 120 is the thickness before lamination of the connection member 120, the thickness L2 of the first encapsulation layer 131 is the thickness before lamination of the first encapsulation layer 131, and the thickness L3 of the second encapsulation layer 132 is the thickness before lamination of the second encapsulation layer 132.

In some embodiments, referring to fig. 4, the maximum thickness L1 of the connection member 120 in the Z direction is 200 μm to 260 μm, and may be, for example: 200 μm, 210 μm, 230 μm, 235 μm or 250 μm. Excessive thickness L1 of the connecting member 120 may result in excessive use of the connecting member 120, thereby increasing the cost of the photovoltaic module. Too small a maximum thickness L1 of the connection member 120 may result in too small a conductive cross-sectional area of the connection member 120, which may result in too large a resistance loss. Therefore, setting the maximum thickness L1 of the connection member 120 to be 200 μm to 260 μm is beneficial to ensuring that the size of the connection member 120 is within a reasonable range, to avoiding increasing the cost of the photovoltaic module, to reducing the resistance loss, and to improving the efficiency of the photovoltaic module.

In some embodiments, referring to fig. 1 and 4, the thickness L2 of the first encapsulation layer 131 along the Z direction is 110 μm to 200 μm, and may be, for example: 120 μm, 130 μm, 150 μm, 165 μm or 180 μm. The first encapsulation layer 131 having an excessive thickness may affect light absorption of the battery cell 100. The thickness L2 of the first encapsulation layer 131 is too small, which may cause the first encapsulation layer 131 to fail to perform a good blocking of the second encapsulation layer 132 having a larger mobility during the scorching stage of the encapsulation layer in the lamination process, so that the second encapsulation layer 132 flows between the gate line 110 and the connection part 120. Therefore, the thickness L2 of the first encapsulation layer 131 is set to be 110 μm to 200 μm, which is beneficial to avoiding the excessively thick first encapsulation layer 131 from shielding the illumination, i.e. to ensure that the battery chip 100 has a higher utilization rate of the illumination; on the other hand, the first encapsulation layer 131 is beneficial to ensure that the second encapsulation layer 132 is effectively blocked, so that good contact between the gate line 110 and the connection component 120 is beneficial to ensure.

In some embodiments, referring to fig. 1 and 4, the thickness L3 of the second encapsulation layer 132 along the Z direction is 140 μm to 320 μm, which may be, for example: 150 μm, 165 μm, 170 μm, 200 μm or 250 μm. The second packaging layer 132 with too small a thickness cannot perform good packaging protection on the battery plate 100, which may cause the cover plate to be separated from the battery plate 100. Moreover, the second packaging layer 132 with too small a thickness may cause the overall thickness of the packaging layer 130 to be too small, which may cause moisture to enter the battery cell 100 and cause the battery cell 100 to fail. The second encapsulation layer 132 having an excessive thickness may affect the light absorption of the battery cell 100. In addition, the second encapsulation layer 132 having an excessive thickness may cause an increase in manufacturing cost of the photovoltaic module. Therefore, the thickness L3 of the second packaging layer 132 is set to 140 μm-320 μm, which is not only beneficial to ensuring good packaging protection of the second packaging layer 132 on the battery piece 100, but also beneficial to enhancing the utilization rate of the battery piece 100 on illumination, and making the material consumption for preparing the second packaging layer 132 reasonable, which is beneficial to realizing the light weight of the photovoltaic module and reducing the preparation cost of the photovoltaic module.

In some embodiments, referring to fig. 1 and 2, the photovoltaic module further comprises: the glue point 140, the glue point 140 is located between a part of the battery plate 100 and the connecting component 120, and the glue point 140 is located on the surface of the battery plate 100 outside the grid line 110. The glue sites 140 are used to fix the connection members 120 before lamination, preventing the connection members 120 from moving on the surface of the battery sheet 100.

In some embodiments, referring to fig. 1, the photovoltaic module further comprises: the cover plate 150, the cover plate 150 is located on the surface of the encapsulation layer 130 away from the battery plate 100, and the cover plate 150 may be a glass cover plate or a plastic cover plate or the like for protecting the battery string.

In the photovoltaic module provided in the above embodiment, the encapsulation layer 130 includes the first encapsulation layer 131 adjacent to the surface of the battery plate 100 and the connection component 120, and the second encapsulation layer 132 far away from the battery plate 100, and the mobility of the first encapsulation layer 131 is smaller than the mobility of the second encapsulation layer 132, where the mobility of the first encapsulation layer 131 and the mobility of the second encapsulation layer 132 are both the mobility at the lamination temperature, that is, the photovoltaic module is the photovoltaic module in the lamination process, and the first encapsulation layer 131 adjacent to the connection component 120 and the battery plate 100 is set to be in a state with smaller mobility at the lamination temperature, so that the connection component 120 and the grid line 110 are prevented from being in poor contact, thereby being beneficial to improving the efficiency and yield of the photovoltaic module. In addition, the first packaging layer 131 is utilized to isolate the second packaging layer 132 with relatively large mobility, and the second packaging layer 132 with relatively large mobility is utilized to ensure that the packaging layer 130 has large crosslinking degree, so that the packaging layer 130 is ensured to well protect the battery, and the bonding strength of the packaging layer 130 and the cover plate is improved, thereby being beneficial to prolonging the service life of the photovoltaic module.

According to some embodiments of the present application, another aspect of the embodiments of the present application further provides a method for manufacturing a photovoltaic module, where the method for manufacturing a photovoltaic module may be used to form a photovoltaic module related to the foregoing embodiments, and description will be given below of the method for manufacturing a photovoltaic module provided in the embodiments of the present application with reference to the accompanying drawings.

Fig. 5 is a schematic structural diagram corresponding to a step of providing a battery sheet in a method for manufacturing a photovoltaic module according to an embodiment of the present disclosure; fig. 6 is a schematic structural diagram corresponding to a step of dispensing in a preparation method of a photovoltaic module according to an embodiment of the present application; fig. 7 is a schematic structural diagram corresponding to a step of fixing a connecting component by using glue points in a method for manufacturing a photovoltaic module according to an embodiment of the present disclosure; fig. 8 is a schematic structural diagram corresponding to a step of disposing an encapsulation layer in a method for manufacturing a photovoltaic module according to an embodiment of the present application; fig. 9 is a schematic structural diagram of a photovoltaic module after lamination treatment in the method for manufacturing a photovoltaic module according to an embodiment of the present application. Fig. 5 to 9 illustrate only one cell, with the number of cells omitted.

Referring to fig. 5, the method of manufacturing a photovoltaic module includes: a plurality of battery cells 100 are provided, and each of the battery cells 100 has a surface with a plurality of gate lines 110. In some embodiments, the gate lines 110 may be formed using a screen printing and sintering process.

Referring to fig. 6 to 7, a connection member 120 is provided at the surface of the battery sheet 100.

In some embodiments, providing the connection component further comprises: forming glue sites 140. Referring to fig. 6, uncured glue sites 140 may be formed on a portion of the surface of the battery sheet 100 other than the grid lines 110; referring to fig. 7, the connection member 120 is laid on the surface of the battery sheet 100 with the adhesive dots 140 between a portion of the battery sheet 100 and the connection member 120, and after the connection member 120 is laid, the adhesive dots 140 may be cured by ultraviolet irradiation or other low temperature treatment, and the connection member 120 is fixed by the adhesive dots 140 to prevent the connection member 120 from moving.

Referring to fig. 8, an encapsulation layer 130 is disposed on the surface of the battery cell 100, and the encapsulation layer 130 is located at a side of the connection member 120 away from the battery cell 100, and the encapsulation layer 130 includes a first encapsulation layer 131 and a second encapsulation layer 132 sequentially arranged in a direction away from the battery cell 100.

With continued reference to fig. 8, in some embodiments, the encapsulation layer 130 is provided while a cover plate 150 is also provided on the surface of the encapsulation layer 130 remote from the battery.

Referring to fig. 9, the battery cell 100, the connection member 120, and the encapsulation layer 130 are laminated at a preset temperature such that a portion of the connection member 120 located above the gate line 110 is in contact with an adjacent portion of the gate line 110, and such that the battery cell 100 is fixed to the encapsulation layer 130; wherein, the fluidity of the first encapsulation layer 131 at the preset temperature is smaller than the fluidity of the second encapsulation layer 132 at the preset temperature.

In some embodiments, the lamination process also secures the encapsulation layer 130 to the cover plate 150.

The first encapsulation layer 131 adjacent to the connection part 120 and the battery piece 100 is set to be in a state with smaller fluidity, so that poor contact between the connection part 120 and the grid line 110 caused by the fact that the first encapsulation layer 131 flows between the connection part 120 and the grid line 110 is avoided, and the efficiency and the yield of the photovoltaic module are improved. And, utilize first encapsulation layer 131 to keep apart relatively great second encapsulation layer 132 of mobility, utilize the great second encapsulation layer 132 of mobility to guarantee the adhesion strength of second encapsulation layer 132 and apron, and then utilize encapsulation layer 130 to realize the good protection to the battery to be favorable to promoting photovoltaic module life-span.

It should be noted that the preset temperature may be higher than the temperature at which the connection member 120 and the gate line 110 form an alloy and lower than the temperature at which the encapsulation layer 130 performs a cross-linking reaction, so that the connection member 120 and the gate line 110 form an alloy at the preset temperature, and after the connection member 120 and the gate line 110 form an alloy, the encapsulation layer 130 performs a cross-linking reaction.

In the method for manufacturing the photovoltaic module provided in the above embodiment, the first encapsulation layer 131 adjacent to the connection member 120 and the battery piece 100 is set to have a smaller fluidity, so that poor contact between the connection member 120 and the grid line 110 caused by the first encapsulation layer 131 flowing between the connection member 120 and the grid line 110 is avoided, which is beneficial to forming a photovoltaic module with higher yield and efficiency. And, utilize first encapsulation layer 131 to keep apart relatively great second encapsulation layer 132 of mobility, utilize the great second encapsulation layer 132 of mobility to guarantee that encapsulation layer 130 has great crosslinking degree, and then guarantee that encapsulation layer 130 carries out good protection to the battery to and improve encapsulation layer 130 and apron bonding strength, thereby be favorable to forming the photovoltaic module that structural stability is higher.

It should be noted that, in the drawings provided in this embodiment, the structure of the photovoltaic module and the shape of the photovoltaic module do not form the limitation of the structure of the photovoltaic module and the shape of the photovoltaic module in this embodiment, and it can be understood that the structure of the photovoltaic module and the shape of the photovoltaic module can be correspondingly designed and modified according to the photovoltaic module matched with the requirements.

It will be understood by those of ordinary skill in the art that the foregoing embodiments are specific examples of implementing 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. Various changes and modifications may be made by one skilled in the art without departing from the spirit and scope of the invention, and the scope of the invention shall be defined by the appended claims.

Claims

1. A photovoltaic module, comprising:

a plurality of battery pieces, wherein the surface of each battery piece is provided with a plurality of grid lines;

the connecting parts are positioned on the surfaces of the battery pieces and are respectively connected with adjacent battery pieces, and the parts positioned on the grid lines are in contact connection with the adjacent parts of the grid lines;

the packaging layer covers the surface of the battery piece and the surface of the connecting part, and the packaging layer comprises a first packaging layer and a second packaging layer which are sequentially distributed along the direction away from the battery piece, wherein the fluidity of the first packaging layer is smaller than that of the second packaging layer.

2. The photovoltaic module of claim 1, wherein the ratio of the ML value of the first encapsulant layer to the ML value of the second encapsulant layer is 1.5-8.5.

3. The photovoltaic module according to claim 1 or 2, wherein the ML value of the first encapsulation layer is 0.4 dN-m to 0.85 dN-m and/or the ML value of the second encapsulation layer is 0.1 dN-m to 0.3 dN-m.

4. The photovoltaic module of claim 1, further comprising: and the glue point is positioned between part of the battery piece and the connecting part, and is positioned on the surface of the battery piece outside the grid line.

5. The photovoltaic assembly of claim 1, wherein the first and second encapsulant layers are an integrally formed structure.

6. The photovoltaic module according to claim 1, wherein a ratio of a thickness of the first encapsulation layer to a maximum thickness of the connection member in a direction in which the battery sheet is directed toward the encapsulation layer is 0.4 to 1.

7. The photovoltaic module of claim 1, wherein a ratio of a thickness of the first encapsulant layer to a thickness of the second encapsulant layer in a direction in which the cell sheet is directed toward the encapsulant layer is 0.3 to 1.5.

8. The photovoltaic module of claim 1, wherein the material of the first encapsulant layer and the material of the second encapsulant layer are the same.

9. A method of manufacturing a photovoltaic module, comprising:

providing a plurality of battery pieces, wherein the surface of each battery piece is provided with a plurality of grid lines;

a connecting component is arranged on the surface of the battery piece;

arranging an encapsulation layer on the surface of the battery piece, wherein the encapsulation layer is positioned on one side of the connecting part far away from the battery piece, and the encapsulation layer comprises a first encapsulation layer and a second encapsulation layer which are sequentially arranged along the direction far away from the battery piece;

Laminating the battery piece, the connecting component and the packaging layer at a preset temperature to enable the connecting component positioned above the grid line to be in contact connection with the adjacent grid line and enable the battery piece to be fixed with the packaging layer;

the fluidity of the first packaging layer at the preset temperature is smaller than that of the second packaging layer at the preset temperature.

10. The method of manufacturing a photovoltaic module according to claim 9, wherein providing the connection member further comprises: and forming glue points, wherein the glue points are positioned between part of the battery pieces and the connecting parts, and the glue points are positioned on the surfaces of the battery pieces outside the grid lines.