US-20260129999-A1 - METHOD FOR MANUFACTURING CELL STRING, METHOD FOR MANUFACTURING PHOTOVOLTAIC MODULE, AND PHOTOVOLTAIC MODULE

US20260129999A1US 20260129999 A1US20260129999 A1US 20260129999A1US-20260129999-A1

Abstract

A method for manufacturing a cell string, a method for manufacturing a photovoltaic module are provided. The method includes: providing a plurality of slicing cell sheets, the plurality of slicing cell sheets include a first slicing cell sheet and a second slicing cell sheet, at least one surface of the first slicing cell sheet includes a stacking area, and a first buffer adhesive film is laid in the stacking area; laying first welding strips over the at least one surface of the first slicing cell sheet; stacking a first part of the second slicing cell sheet over the stacking area of the first slicing cell sheet and a second part of the second slicing cell sheet over a third portion of the first welding strips; performing welding to electrically interconnecte the second slicing cell sheet with the first slicing cell sheet via the first welding strips.

Inventors

Wusong Tao
Luchuang Wang
Xin Wang
Chunqiang Li
Xiangchao HAN

Assignees

Jinko Solar Co., Ltd.
Jinko Solar (Haining) Co., Ltd.

Dates

Publication Date: 20260507
Application Date: 20251031
Priority Date: 20241101

Claims (20)

1 . A method for manufacturing a cell string, comprising: providing a plurality of slicing cell sheets, wherein the plurality of slicing cell sheets include a first slicing cell sheet and a second slicing cell sheet, at least one surface of the first slicing cell sheet has a stacking area, and a first buffer adhesive film is laid in the stacking area; laying first welding strips over the at least one surface of the first slicing cell sheet, the first welding strips having a first portion paid on a portion of the at least one first surface, a second portion covering a part of the first buffer adhesive film and a third portion extending beyond the at least one first surface; stacking a first part of the second slicing cell sheet over the stacking area of the first slicing cell sheet and a second part of the second slicing cell sheet over the third portion of the first welding strips; and performing welding to electrically interconnect the second slicing cell sheet with the first slicing cell sheet via the first welding strips.
2 . The manufacturing method according to claim 1 , wherein in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film has a width greater than or equal to a width of the stacking area.
3 . The manufacturing method according to claim 1 , wherein in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film protrudes from an end portion of the first slicing cell sheet.
4 . The manufacturing method according to claim 1 , wherein in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film has a width ranging from 3 mm to 10 mm; and in a direction perpendicular to the arrangement direction of the plurality of slicing cell sheets, the first buffer adhesive film has a length ranging from 6 mm to 13 mm.
5 . The manufacturing method according to claim 1 , further including: before laying the first welding strips over the at least one surface of the first slicing cell sheet, performing a heat fixing treatment on the first buffer adhesive film, wherein the heat fixing treatment includes heating the first buffer adhesive film to bond the first buffer adhesive film on the surface of the first slicing cell sheet.
6 . The manufacturing method according to claim 5 , wherein process parameters of the heat fixing treatment include: a heating temperature ranging from 60° C. to 70° C. and a heating time period ranging from 0.5 s to 1.5 s.
7 . The manufacturing method according to claim 1 , wherein the welding includes laser welding, and the laser welding includes: controlling a laser to irradiate a surface of the first welding strips to weld the first welding strips to surfaces of the slicing cell sheets.
8 . The manufacturing method according to claim 1 , the method further includes: providing a plurality of solder joints on the slicing cell sheets, wherein the first welding strips are in contact with the plurality of solder joints, and in an arrangement direction of the slicing cell sheets in the cell string, a width of the first buffer adhesive film is less than a distance between the two nearest solder joints of the first and second slicing cell sheets.
9 . The manufacturing method according to claim 1 , wherein a respective first welding strip of the first welding strips includes a main portion and a connecting portion connecting the main portion, wherein the main portion has a thickness greater than a thickness of the connecting portion; the laying of the first welding strips over the at least one surface of the first slicing cell sheet includes: positioning the connecting portion to be directly aligned with the first buffer adhesive film.
10 . The manufacturing method according to claim 9 , wherein a sum of the thickness of the connecting portion and a thickness of the first buffer adhesive film is equal to the thickness of the main portion.
11 . The manufacturing method according to claim 1 , wherein the first buffer adhesive film may be made from a pre-crosslinked adhesive film such as Ethylene Vinyl Acetate Copolymer (EVA), Polyolefin Elastomer (POE), or a co-extruded material of EVA-POE-EVA (EPE).
12 . The manufacturing method according to claim 11 , wherein the first buffer adhesive film is made from an Ethylene Vinyl Acetate Copolymer (EVA) material with a crosslinking degree of 5% to 70%, a Polyolefin Elastomer (POE) material with a crosslinking degree of 5% to 70%, or an EVA-POE-EVA (EPE) material with a crosslinking degree of 5% to 70%.
13 . The manufacturing method according to claim 1 , wherein a respective slicing cell sheet of the plurality of slicing cell sheets is a 3-segmented to 12-segmented cell obtained by cutting an original whole cell sheet into 3 to 12 segments.
14 . The manufacturing method according to claim 1 , wherein a width of a respective of the plurality of slicing cell sheets ranges from 40 to 86 mm, a length of a respective of the plurality of slicing cell sheets ranges from 180 to 260 mm.
15 . The manufacturing method according to claim 1 , wherein the laying of the first buffer adhesive film includes: providing an initial buffer adhesive film; cutting the initial buffer adhesive film to form the first buffer adhesive film; and moving the first buffer adhesive film to the stacking area.
16 . The manufacturing method according to claim 1 , wherein the first slicing cell sheet includes a first surface and a second surface opposite to the first surface, the laying of the first buffer adhesive film comprises: laying the first buffer adhesive film in the stacking area corresponding to the first surface and the second surface.
17 . The manufacturing method according to claim 1 , wherein the first slicing cell sheet is formed by: providing an initial cell sheet; cutting the initial cell sheet to form at least three cell slices; and laying the first buffer adhesive film in the stacking area of a respective cell slice of the at least three cell slices to form the first slicing cell sheet.
18 . The manufacturing method according to claim 1 , wherein the first slicing cell sheet is formed by: providing an initial cell sheet; laying the first buffer adhesive film in the stacking area of the initial cell sheet corresponding to each slicing cell sheet; and cutting the initial cell sheet with the first buffer adhesive film laid thereon to form at least three first slicing cell sheets.
19 . The manufacturing method according to claim 1 , wherein the plurality of slicing cell sheets include edge cell sheets with a cutting surface; the method further includes: before stacking the first part of the second slicing cell sheet over the stacking area of the first slicing cell sheet, adjusting an orientation of the cutting surfaces of the edge cell sheets such that the cutting surfaces of the edge cell sheets face the same direction.
20 . A method for manufacturing a photovoltaic module, comprising: providing a plurality of cell strings, wherein a respective cell string of the plurality of cell strings is the cell string manufactured by the method of claim 1 ; laying second buffer adhesive films on surfaces of the slicing cell sheets at both sides of the respective cell string, the second buffer adhesive films being located at end portions of the slicing cell sheets; providing second welding strips, the second welding strips being electrically connected to the slicing cell sheets at both sides of the respective cell string and covering surfaces of the second buffer adhesive films; providing busbars, the busbars being electrically connected to the second welding strips and electrically connected to the plurality of cell strings via the second welding strips; forming at least one encapsulating adhesive film, the at least one encapsulating adhesive film being configured to cover surfaces of the plurality of cell strings; and forming a cover plate, the cover plate being configured to cover a surface of the at least one encapsulating adhesive film facing away from the plurality of cell strings.

Description

CROSS REFERENCE TO RELATED APPLICATIONS The present application claims the benefit of priority under the Paris Convention to Chinese Patent Application No. CN202411555181.4, entitled “METHOD FOR MANUFACTURING CELL STRING, METHOD FOR MANUFACTURING PHOTOVOLTAIC MODULE, AND PHOTOVOLTAIC MODULE,” filed on Nov. 1, 2024, which is incorporated herein by reference in its entirety. TECHNICAL FIELD Embodiments of the present disclosure relate to the photovoltaic field, and in particular to a method for manufacturing a cell string, a method for manufacturing a photovoltaic module, and a photovoltaic module. BACKGROUND Cell string is a structure that connects multiple cell sheets in series to produce more power, preventing situations where a single cell cannot meet the desired voltage and current. Stacked cell strings, as a type of cell strings, are formed by slicing cell sheets and interconnecting front surface edges of preceding slicing cell sheets with back surface edges of subsequent slicing cell sheets. Such a design allows the cell slices to be connected to each other in a more compact manner, and reduces gaps between the cell sheets, which can increase the power of the cell string per unit area, thereby being widely used. However, for the stacked cell strings, there is a problem that overlapping parts of the stacked cell strings are prone to damage. SUMMARY Embodiments of the present disclosure provide a method for manufacturing a cell string, a method for manufacturing a photovoltaic module, and a photovoltaic module. According to some embodiments of the present disclosure, a method for manufacturing a cell string is provided. The method includes: providing a plurality of slicing cell sheets, where the plurality of slicing cell sheets include a first slicing cell sheet and a second slicing cell sheet, at least one surface of the first slicing cell sheet has a stacking area, and a first buffer adhesive film is laid in the stacking area; laying first welding strips over the at least one surface of the first slicing cell sheet, the first welding strips having a first portion paid on a portion of the at least one first surface, a second portion covering a part of the first buffer adhesive film and a third portion extending beyond the at least one first surface; stacking a first part of the second slicing cell sheet over the stacking area of the first slicing cell sheet and a second part of the second slicing cell sheet over the third portion of the first welding strips; and performing welding to electrically interconnect the second slicing cell sheet with the first slicing cell sheet via the first welding strips. In some embodiments, in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film has a width greater than or equal to a width of the stacking area. In some embodiments, in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film protrudes from an end portion of the first slicing cell sheet. In some embodiments, in an arrangement direction of the plurality of slicing cell sheets in the cell string, the first buffer adhesive film has a width ranging from 3 mm to 10 mm; and in a direction perpendicular to the arrangement direction of the plurality of slicing cell sheets, the first buffer adhesive film has a length ranging from 6 mm to 13 mm. In some embodiments, the method further including: before laying the first welding strips over the at least one surface of the first slicing cell sheet, performing a heat fixing treatment on the first buffer adhesive film, where the heat fixing treatment includes heating the first buffer adhesive film to bond the first buffer adhesive film on the surface of the first slicing cell sheet. In some embodiments, process parameters of the heat fixing treatment include: a heating temperature ranging from 60° C. to 70° C. and a heating time period ranging from 0.5 s to 1.5 s. In some embodiments, the welding includes laser welding, and the laser welding includes: controlling a laser to irradiate a surface of the first welding strips to weld the first welding strips to surfaces of the slicing cell sheets. In some embodiments, the method further includes providing a plurality of solder joints on the slicing cell sheets, the first welding strips are in contact with the plurality of solder joints, and in an arrangement direction of the slicing cell sheets in the cell string, a width of the first buffer adhesive film is less than a distance between the two nearest solder joints of the first and second slicing cell sheets. In some embodiments, a respective first welding strip of the first welding strips includes a main portion and a connecting portion connecting the main portion, where the main portion has a thickness greater than a thickness of the connecting portion; the laying of the first welding strips over the at least one surface of the first slicing cell sheet i