Solar cell module manufacturing method, and solar cell module

Abstract

A solar cell module manufacturing method, and a solar cell module, which are applied to the technical field of solar cells. The method comprises: laying a plurality of cells and welding strips on a whole continuous inner-layer encapsulation adhesive film, and encapsulating the welding strips on the surfaces of the cells by means of an inner-layer encapsulation adhesive film, so as to form cell strings; connecting the cell strings to each other; and laminating and encapsulating a front cover plate, the cell strings connected to each other and a back plate by means of an outer-layer encapsulation adhesive film, so as to form a laminated member; and preparing a solar cell module on the basis of the laminated member. By means of two totally successive encapsulations, in the first encapsulation, the welding strips are connected to the cells by means of the adhesive film, and in the second encapsulation, the cell strings are encapsulated, such that uniform and high-quality encapsulation can be realized; by means of increasing the amount of the adhesive film in a cell gap, laminated bubbles due to local shortages of an adhesive of a low-flow adhesive film can be eliminated; and high-density encapsulation between the cell strings can be achieved by means of two encapsulations, and the efficiency of a photovoltaic module is improved.

Description

A method for manufacturing a solar cell module and a solar cell module

[0001] This application claims priority to the Chinese patent application filed with the Patent Office of China on December 4, 2023, with application number 202311647091.3 and invention name “A method for manufacturing a solar cell module and a solar cell module”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present invention relates to the technical field of solar cells, and in particular to a method for manufacturing a solar cell assembly and a solar cell assembly. Background Art

[0003] Busbar-less and dense-grid technologies replace the cell's silver busbar and flat solder ribbons with multiple thin copper wires (ribbons) coated with a special coating. This significantly reduces the frontal shading area of ​​the cell while also reducing silver paste consumption, thereby improving the conversion efficiency of photovoltaic modules and lowering manufacturing costs. However, this technology requires laying dozens of thin tinned copper wires (ribbons) on the cell and welding them to the fine grid lines. A film material is required to pre-arrange and secure the tinned copper wires (ribbons) and support them in place during the lamination and welding process.

[0004] Conventional adhesive films are laminated directly onto the outside of the cell strings, sealing all cells within the entire module simultaneously against the wind. During the lamination process, cells on the inside of the adhesive film are subjected to uneven pressure or slippage between the cells and the film. This prevents the module design from achieving close cell string spacing, which in turn prevents high-density packaging. Furthermore, this relative slippage can easily lead to loss of contact between cell strings, causing electrical shorts within the module and significant losses. Therefore, developing a method for manufacturing solar cell modules with a high yield is an urgent challenge for those skilled in the art.

[0005] Summary of the Invention

[0006] An object of the present invention is to provide a method for manufacturing a solar cell module with a high yield rate; another object of the present invention is to provide a solar cell module with a high yield rate.

[0007] To solve the above technical problems, the present invention provides a method for manufacturing a solar cell module, comprising:

[0008] Laying multiple battery cells and welding ribbons on a continuous inner packaging film, and encapsulating the welding ribbons on the surface of the battery cells through the inner packaging film to form a battery string; the inner packaging film is used to fix the welding ribbons to the surface of the battery cells;

[0009] connecting the battery strings to each other;

[0010] The front cover plate, the interconnected battery strings and the back plate are laminated and encapsulated by an outer packaging film to form a laminate; the outer packaging film is located between the battery string and the front cover plate, and between the battery string and the back plate;

[0011] The solar cell module is produced based on the laminate.

[0012] Optionally, laying the plurality of battery cells and the welding ribbons on a continuous inner packaging film, and encapsulating the welding ribbons on the surface of the battery cells through the inner packaging film to form a battery string includes:

[0013] Laying a continuous first inner layer packaging film on the surface of the base plate;

[0014] Laying welding ribbons and multiple battery cells on the surface of the first inner packaging film according to a preset battery string structure;

[0015] A second inner packaging film corresponding to each cell is laid on the surface of the cell facing away from the bottom plate; the first inner packaging film and the second inner packaging film are both used to securely connect the soldering ribbon to the surface of the cell; and there are gaps between adjacent second inner packaging films;

[0016] A press is placed on the surface of the second inner packaging film and heated to seal the solder ribbon on the surface of the battery cell to form a battery string.

[0017] Optionally, the bottom plate has an adsorption structure to adsorb the first inner packaging film.

[0018] Optionally, a hollow structure is provided in a non-encapsulation area outside the welding strip corresponding to the first inner packaging film, so that the adsorption structure can adsorb the battery cell through the hollow structure.

[0019] Optionally, a hollow structure is provided in a non-encapsulation area outside the welding strip corresponding to the second inner packaging film.

[0020] Optionally, the second inner packaging film is a plurality of films covering welding strips on the surface of the battery cell facing away from the bottom plate.

[0021] Optionally, the battery cell includes a busbar-less battery cell, and the welding ribbon is a low-temperature welding ribbon.

[0022] Optionally, the outer packaging film has greater fluidity than the inner packaging film.

[0023] Optionally, manufacturing the solar cell assembly based on the laminate comprises:

[0024] The laminate is subjected to edge frame protection and lead-out terminal box installation to manufacture the solar cell assembly.

[0025] Optionally, connecting the battery strings to each other includes:

[0026] The edges of adjacent battery strings are isolated from each other and stacked by an inner packaging film that extends beyond the sides of the battery cells, so as to overlap the battery strings.

[0027] Optionally, isolating and stacking edges of adjacent battery strings by an inner packaging film extending beyond the sides of the battery cells to overlap the battery strings includes:

[0028] The edges of adjacent battery strings are isolated from each other and stacked by a first inner layer packaging film extending beyond the side surfaces of the battery strings, so as to overlap the battery strings.

[0029] Optionally, laying a second inner layer packaging film corresponding to each battery cell on the surface of the battery cell facing away from the bottom plate includes:

[0030] The edges of adjacent battery cells are isolated from each other and stacked by a second inner layer packaging film extending beyond the side surfaces of the battery cells, so as to overlap the battery cells.

[0031] The present invention also provides a solar cell assembly, comprising a cell string, an outer packaging film, a front cover plate and a back plate;

[0032] The battery string is formed by laying multiple battery cells and welding ribbons on a continuous inner packaging film, and the welding ribbons are encapsulated on the surface of the battery cells through the inner packaging film; the inner packaging film is used to fix the welding ribbons to the surface of the battery cells;

[0033] The plurality of battery strings are connected to each other, and the outer packaging film connects the front cover plate, the interconnected battery strings and the back plate to each other.

[0034] Optionally, the inner packaging film includes a continuous first inner packaging film and a second inner packaging film corresponding to the battery cell;

[0035] The plurality of battery cells and welding ribbons in the battery string are laid on the surface of the first inner packaging film according to the preset battery string structure, and the second inner packaging film is laid on the surface of the battery cells facing away from the first inner packaging film, and there are gaps between adjacent second inner packaging films.

[0036] Optionally, edges of adjacent battery strings are isolated from each other and stacked by an inner packaging film extending beyond the sides of the battery, so that the battery strings are overlapped.

[0037] Optionally, edges of adjacent battery strings are isolated from each other and stacked by a first inner layer packaging film extending beyond the side surfaces of the battery strings, so that the battery strings are overlapped.

[0038] Optionally, edges of adjacent battery cells in the battery string are isolated from each other and stacked by a second inner layer of packaging film extending beyond the sides of the battery cells, so that the battery cells are overlapped.

[0039] Optionally, the second inner packaging film corresponds one-to-one to the welding strip on one side of the battery cell, and the second inner packaging film encapsulates the corresponding welding strip on the surface of the battery cell.

[0040] The present invention provides a method for manufacturing a solar cell module, comprising: laying a plurality of cell sheets and welding ribbons on a whole continuous inner packaging film, and packaging the welding ribbons on the surface of the cell sheets through the inner packaging film to form a cell string; the inner packaging film is used to fix the welding ribbons to the surface of the cell sheets; the cell strings are connected to each other; the front cover plate, the interconnected cell strings and the back plate are laminated and packaged through the outer packaging film to form a laminate; the outer packaging film is located between the cell string and the front cover plate, and between the cell string and the back plate; and the solar cell module is manufactured based on the laminate.

[0041] Through a total of two packaging processes, the first packaging connects the welding ribbon to the battery cell through the adhesive film, and the second packaging encapsulates the battery string, which can achieve uniform and high-quality packaging; by increasing the amount of adhesive film in the battery gap, the lamination bubbles caused by local adhesive deficiency of low-flow adhesive film can be eliminated; the secondary packaging can achieve high-density packaging between battery strings, thereby improving the efficiency of photovoltaic modules.

[0042] The present invention also provides a solar cell assembly, which also has the above-mentioned beneficial effects and will not be described in detail here. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions of the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0044] FIG1 is a flow chart of a method for manufacturing a solar cell module provided by an embodiment of the present invention;

[0045] FIG2 is a flow chart of a specific method for manufacturing a solar cell module provided by an embodiment of the present invention;

[0046] FIG3 is a schematic diagram of the first packaging of an embodiment of the present invention;

[0047] FIG4 is a schematic side view of the structure of a battery string during the first packaging;

[0048] FIG5 is a schematic diagram of the top view of the battery string during the first packaging;

[0049] FIG6 is a schematic diagram of the bottom view of the battery string during the first packaging;

[0050] FIG7 is a schematic diagram of the structure of the connection between adjacent battery strings;

[0051] FIG8 is a schematic diagram of a test structure of FIG7 ;

[0052] FIG9 is a schematic top view of the structure of the first encapsulation in the first method for manufacturing a solar cell module;

[0053] FIG10 is a bottom view of the structure of the first encapsulation in the first method for manufacturing a solar cell module;

[0054] FIG11 is a schematic top view of the first packaging structure in the second method for manufacturing a solar cell module;

[0055] FIG12 is a bottom view of the structure of the first encapsulation in the second method for manufacturing a solar cell module;

[0056] FIG13 is a schematic top view of the first packaging structure in the third method for manufacturing a solar cell module;

[0057] FIG14 is a bottom view of the structure of the first encapsulation in the third method for manufacturing a solar cell module;

[0058] FIG15 is a schematic top view of the structure of the first packaging in the fourth method for manufacturing a solar cell module.

[0059] In the figure: 1. Battery cell, 2. Solder ribbon, 3. Inner encapsulation film, 31. First inner encapsulation film, 32. Second inner encapsulation film, 33. Hollow structure, 4. Bottom plate, 41. Adsorption structure, 42. Heating source, 5. Elastomer, 6. Press, 7. Overlapping area. DETAILED DESCRIPTION

[0060] The core of the present invention is to provide a method for manufacturing a solar cell module. In the prior art, conventional adhesive films are directly applied to the outside of a cell string for lamination, sealing all cells within the entire module at once against the wind. During the lamination process, cells on the inside of the adhesive film are subjected to uneven pressure or slippage between the cells and the film. This prevents the module design from achieving close cell string spacing, meaning high-density packaging is impossible. Furthermore, the relative slippage of the cells can easily lead to a loss of contact between the cell strings, causing electrical shorts within the module and significant losses.

[0061] The present invention provides a method for manufacturing a solar cell module, comprising: laying a plurality of cell sheets and welding ribbons on a whole continuous inner packaging film, and packaging the welding ribbons on the surface of the cell sheets through the inner packaging film to form a cell string; the inner packaging film is used to fix the welding ribbons to the surface of the cell sheets; the cell strings are connected to each other; the front cover plate, the interconnected cell strings and the back plate are laminated and packaged through the outer packaging film to form a laminate; the outer packaging film is located between the cell string and the front cover plate, and between the cell string and the back plate; and the solar cell module is manufactured based on the laminate.

[0062] Through a total of two packaging processes, the first packaging connects the welding ribbon to the battery cell through the adhesive film, and the second packaging encapsulates the battery string, which can achieve uniform and high-quality packaging; by increasing the amount of adhesive film in the battery gap, the lamination bubbles caused by local adhesive deficiency of low-flow adhesive film can be eliminated; the secondary packaging can achieve high-density packaging between battery strings, thereby improving the efficiency of photovoltaic modules.

[0063] In order to enable those skilled in the art to better understand the present invention, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0064] Please refer to FIG1 , which is a flow chart of a method for manufacturing a solar cell assembly provided by an embodiment of the present invention.

[0065] Referring to FIG1 , in an embodiment of the present invention, a method for manufacturing a solar cell assembly includes:

[0066] S101: Laying multiple battery cells and welding ribbons on a continuous inner packaging film, and sealing the welding ribbons on the surface of the battery cells through the inner packaging film to form a battery string.

[0067] In this embodiment of the present invention, the inner encapsulation film 3 is used to securely connect the soldering ribbon 2 to the surface of the battery cell 1. Therefore, in this embodiment, the inner encapsulation film 3 is a low-flowability film, which can improve the securing effect and reduce the occurrence of undesirable conditions such as cold soldering and over-soldering. Specifically, this step first involves setting up a continuous inner encapsulation film 3, and then placing multiple battery cells 1 and their corresponding soldering ribbons 2 on the surface of the continuous inner encapsulation film 3 for encapsulation to form a battery string. For a battery string, the continuous inner encapsulation film 3 extends from one end of the battery string to the other without breaking.

[0068] This step is equivalent to the first packaging of the cell 1 and the solder ribbon 2, which fixes the cell 1 and the solder ribbon 2 relative to each other to form a battery string. Therefore, the adhesive film used in this step is a low-flow adhesive film, which is used to fix the cell 1 and the solder ribbon 2 relative to each other.

[0069] In this embodiment, the above-mentioned battery cell 1 includes a busbar-free battery cell 1, and the above-mentioned welding ribbon 2 is a low-temperature welding ribbon. That is, the above-mentioned inner layer packaging film 3 is mainly used to achieve relative fixation between the busbar-free battery cell 1 and the welding ribbon 2. Of course, in this embodiment, the above-mentioned battery cell 1 can be a PERC (Passivated Emitter and Rear Cell, emitter back passivation) battery, TOPCon (Thin Oxide Passivated Contact, tunneling oxide layer passivated contact) battery, HJT (Hereto-junction with Intrinsic Thin-layer heterojunction) battery, back contact battery, including but not limited to busbar-free batteries. The above-mentioned welding ribbon 2 is usually a low-temperature welding ribbon with an outer surface melting point of 90°C to 137°C. Of course, in this embodiment, there is no specific limitation on the type of battery cell 1 and the type of welding ribbon 2, which depends on the specific situation.

[0070] In this embodiment, the inner packaging film 3 needs to wrap at least 80% of the length of the solder ribbon 2 , and the inner packaging film 3 only forms a weak bond with the battery cell 1 , and the end of the solder ribbon 2 is not limited to be covered.

[0071] In this embodiment, the inner encapsulation film 3 may be PVB (polyvinyl butyral), EVA (ethylene-vinyl acetate copolymer) with a cross-linking degree ranging from 10% to 75%, POE (polyolefin elastomer), or a polyolefin material. The thickness of a single layer of the inner encapsulation film 3 is typically 10 μm to 900 μm, inclusive. The details of this step will be described in detail in the following embodiments and will not be further elaborated here.

[0072] S102: Connect the battery strings to each other.

[0073] In this step, the formed battery strings need to be connected in series or parallel, and busbars and other structures need to be installed to connect the battery strings. In this embodiment, the spacing between adjacent battery strings is generally -1mm to 1.5mm to ensure a small spacing between battery strings and a high arrangement density of the final solar cell module.

[0074] S103: The front cover plate, the interconnected battery strings and the back plate are laminated and packaged by an outer packaging film to form a laminate.

[0075] In this embodiment, the outer packaging film is located between the battery string and the front cover, and between the battery string and the back plate.

[0076] This step will specifically perform a second packaging on the battery string. This second packaging is similar to traditional packaging, and requires the front cover plate, battery string and back plate to be laminated and connected through an outer packaging film to form a laminate. The above-mentioned front cover plate can be a front glass or a front transparent plate, and the above-mentioned back plate can be a back glass or a back metal plate; the above-mentioned connected battery string is located in the middle, and an outer packaging film is provided between the battery string and the front cover plate for connection, and an outer packaging film is also provided between the battery string and the back plate for connection. The outer packaging film, front cover plate, battery string and back plate of the above-mentioned stacked structure will be packaged by lamination. The above-mentioned outer packaging film can be a co-extruded structure of one or more of PVB, EVA, POE or polyolefin materials, and its thickness is generally 10um to 5mm, including end values.

[0077] Since the solder ribbon 2 and the cell 1 are pre-secured by an inner encapsulating film 3 in this embodiment, the outer encapsulating film used in this step can be a high-flow film. Specifically, in this embodiment, the outer encapsulating film must have greater fluidity than the inner encapsulating film 3. This high-flow film can effectively fill the gaps between the cell strings and prevent the formation of bubbles in the laminate. Of course, a low-flow film can also be used as the outer encapsulating film in this embodiment, without specific limitation.

[0078] S104: Manufacturing a solar cell module based on the laminate.

[0079] In this step, related components, such as an outer frame, connectors, etc., are arranged based on the above-mentioned laminate to produce a solar cell module.

[0080] A method for manufacturing a solar cell module provided by an embodiment of the present invention achieves uniform and high-quality packaging through a total of two packaging processes: the first packaging connects the solder ribbon 2 to the cell 1 through an adhesive film, and the second packaging encapsulates the cell string. By increasing the amount of adhesive film in the cell gap, lamination bubbles caused by local adhesive deficiency of the low-flow adhesive film can be eliminated. The secondary packaging can achieve high-density packaging between the cell strings, thereby improving the efficiency of the photovoltaic module.

[0081] The specific contents of the method for manufacturing a solar cell assembly provided by the present invention will be described in detail in the following embodiments of the invention.

[0082] Please refer to Figures 2 to 8, Figure 2 is a flow chart of a specific method for manufacturing a solar cell module provided by an embodiment of the present invention; Figure 3 is a schematic diagram of the first packaging of an embodiment of the present invention; Figure 4 is a side view structural schematic diagram of the battery string during the first packaging; Figure 5 is a top view structural schematic diagram of the battery string during the first packaging; Figure 6 is a bottom view structural schematic diagram of the battery string during the first packaging; Figure 7 is a structural schematic diagram of the connection between adjacent battery strings; and Figure 8 is a test structure schematic diagram of Figure 7.

[0083] Referring to FIG2 , in an embodiment of the present invention, a method for manufacturing a solar cell assembly includes:

[0084] S201: Laying a continuous first inner layer packaging film on the surface of the base plate.

[0085] Referring to Figure 3, the base plate 4 used in this embodiment specifically needs to have a movable bottom and include a bottom adsorption base plate 4, wherein the movable bottom ensures that the battery cell 1 can be moved for packaging, and the bottom adsorption means that the base plate 4 has an adsorption structure 41 for fixing the structure set on the surface of the base plate 4.

[0086] In the step, a whole continuous first inner packaging film 31 is first laid on the surface of the bottom plate 4 so that a battery string can be prepared based on the continuous first inner packaging film 31 later.

[0087] S202: Laying a welding ribbon and a plurality of battery cells on the surface of the first inner packaging film according to a preset battery string structure.

[0088] Referring to Figures 4 and 5, in this step, it is necessary to lay a welding ribbon 2 and multiple battery cells 1 on the surface of the first inner packaging film 31 according to the preset battery string structure. For example, when welding ribbon 2 needs to be set on both sides of the battery cell 1, in this step, the operations of pulling the welding ribbon 2 and placing the battery cell 1 will be performed alternately until a battery string with a preset structure is reached.

[0089] S203: Laying a second inner layer packaging film corresponding to each battery cell on the surface of the battery cell facing away from the bottom plate.

[0090] In this embodiment of the present invention, both the first inner encapsulation film 31 and the second inner encapsulation film 32 are used to securely connect the soldering ribbon 2 to the surface of the cell 1. Therefore, in this embodiment, both the first inner encapsulation film 31 and the second inner encapsulation film 32 are low-flow films. In this step, the second inner encapsulation film 32 is applied to the surface of the cell 1 facing away from the base plate 4. This second inner encapsulation film 32 covers the soldering ribbon 2 disposed on the surface of the cell 1 facing away from the base plate 4, thereby encapsulating the soldering ribbon 2 on both sides of the cell 1. The details of the first inner encapsulation film 31 and the second inner encapsulation film 32 can be found in the details of the inner encapsulation film 3 described above and will not be further elaborated here.

[0091] It should be emphasized that in this embodiment, the second packaging film 32 is the second inner packaging film 32 corresponding to each battery cell 1 itself, that is, one second packaging film 32 corresponds to only one battery cell 1 .

[0092] Referring to FIG. 8 , further, in this embodiment, the above-mentioned S203 may specifically include: isolating the edges of adjacent battery cells 1 from each other and stacking them together using a second inner layer of encapsulating film 32 extending beyond the sides of the battery cells 1 to overlap the battery cells 1. That is, in this embodiment, the above-mentioned second inner layer of encapsulating film 32 can be further used to achieve isolation and stacking between battery cells 1. The second inner layer of encapsulating film 32 is placed in the overlapping region 7 between two stacked battery cells 1, so that the two stacked battery cells 1 are isolated from each other to form a battery string. That is, adjacent battery cells 1 within a single battery string can be isolated and stacked by the second inner layer of encapsulating film 32, thereby improving the problem of hidden cracks in the battery cells 1, eliminating gaps between adjacent battery cells 1, and reducing the non-power generation area of ​​the component.

[0093] The specific structure of the second inner encapsulation film 32 and its specific location on the cell 1 will be described in detail in the following embodiments. It can have various different structures and, accordingly, can form various combinations with the cell 1. One structure includes multiple sheets of the second inner encapsulation film 32, with multiple solder ribbons 2 disposed on one side of the cell 1. Each of the second inner encapsulation films 32 corresponds one-to-one with each solder ribbon 2 on one side of the cell 1, encapsulating the corresponding solder ribbon 2 on the surface of the cell 1. In other words, in this structure, each solder ribbon on the surface of a cell corresponds to a second inner encapsulation film 32, and the second inner encapsulation film 32 extends beyond the edge of the cell 1 to the overlap region 7 to enable stacking of adjacent cells 1. In this structure, multiple individual second inner encapsulation films 32 are used, and during the manufacturing process, the films only need to be rolled and cut, eliminating the need for a robotic arm to pick up the material and reducing the generation of bubbles. Each solder ribbon is covered by the second inner encapsulation film 32, reducing stacking and compressive stress.

[0094] S204: placing a press on the surface of the second inner packaging film and heating it to package the solder ribbon on the surface of the battery cell to form a battery string.

[0095] In this step, a press 6 is placed on the surface of the laid structure to apply pressure. An elastic body 5 can be placed between the press 6 and the second inner packaging film 32. The laid structure is driven to the heating source 42 by the movable bottom plate 4 for heating to perform the first packaging of the battery cells 1 and form a battery string. The heating temperature of the inner packaging film 3 by the heating source 42 is usually between 50°C and 200°C, and the pressure applied by the press 6 to the inner packaging film 3 is usually 0.1N / cm 2 Up to 100N / cm 2 .

[0096] Referring to Figure 6 , it should be emphasized that in this embodiment, the adsorption structure 41 provided on the base plate 4 is used to adsorb the first inner encapsulation film 31 applied to one side of the base plate 4. However, to enhance the base plate 4's ability to secure the cell 1, the first inner encapsulation film 31 preferably includes a hollow structure 33 in the non-encapsulation area outside the solder ribbon 2, allowing the adsorption structure 41 to adsorb the cell 1 through the hollow structure 33. This hollow structure 33 allows the adsorption structure 41 provided on the base plate 4 to directly adsorb the cell 1 through the hollow structure 33, thereby directly securing the cell 1 and preventing relative sliding between the cell 1 and the first inner encapsulation film 31 during the encapsulation process. The hollow structure 33 provided on the first inner encapsulation film 31 can be circular, elliptical, rectangular, or other hollow structures outside the corresponding solder ribbon area, or can be equivalently configured such that the first inner encapsulation film 31 comprises multiple films that only cover the solder ribbon area. The hollow structure 33 can be freely configured based on actual circumstances and is not specifically limited here. In this embodiment, the length of the first inner encapsulation film 31 can be slightly longer or shorter than the length of the battery string. When the first inner encapsulation film 31 is a single layer, its width typically extends 2 mm beyond the outer soldering ribbon, with a maximum of 20 mm extending beyond the battery width on at least one side. When the first inner encapsulation film 31 is comprised of multiple films of the same length covering only the soldering ribbon area, its width typically ranges from 5 mm to 15 mm, with the non-encapsulation area between the multiple films covering only the soldering ribbon area.

[0097] In this embodiment, the second inner encapsulation film 32 is further provided with a hollow structure 33 in the non-encapsulation area corresponding to the outer side of the solder ribbon 2. The hollow structure 33 can also be provided in the non-encapsulation area of ​​the second inner encapsulation film 32. This hollow structure 33 can reduce the amount of encapsulation film used, thereby reducing costs. Furthermore, this hollow structure 33 ensures that the subsequent high-flowability outer encapsulation film can be immersed, eliminating encapsulation bubbles. Furthermore, this structure can prevent damage to the first encapsulation during the subsequent second encapsulation process, thereby avoiding the possibility of cold solder joints.

[0098] Similar to the second inner encapsulating film 32 with the aforementioned hollow structure 33, the second inner encapsulating film 32 can be multiple strips of film covering the soldering ribbon 2 on the side of the cell 1 facing away from the base plate 4. This structure ensures a certain gap between the multiple strips of film, which functions similarly to the hollow structure 33 described above and will not be further described here. When the second inner encapsulating film 32 is a single sheet, its width extends 2mm beyond the outer soldering ribbon and its length is ±5mm along the length of the cell along its placement direction. When the second inner encapsulating film 32 is composed of multiple strips of the same length covering only the soldering ribbon area, its width is typically 5mm to 15mm.

[0099] S205: The edges of adjacent battery strings are isolated and stacked by using the inner packaging film that extends beyond the sides of the battery cells to overlap the battery strings.

[0100] Referring to Figure 7 , in this embodiment, two adjacent battery strings can be connected by overlapping. In this embodiment, the adjacent battery strings have opposing ends, which can be located solely on the surface of a single battery cell 1 or include the ends of multiple battery cells 1. To enhance the robustness of the overlapping connections between the battery strings, in this embodiment, the overlapping ends of the battery strings typically include the ends on one side of multiple battery cells 1.

[0101] An overlapping region 7 exists between two overlapping battery strings. In this embodiment, the edges of adjacent battery strings are isolated and stacked by using an inner encapsulation film 3 extending beyond the sides of the battery cells 1, typically a first inner encapsulation film 31 extending beyond the sides of the battery string. Specifically, this step may include isolating the edges of adjacent battery strings by using the first inner encapsulation film 31 extending beyond the sides of the battery string to overlap the battery strings. The so-called isolation and stacking refers to placing the inner encapsulation film 3 extending beyond the sides of the battery cells 1, typically the first inner encapsulation film 31 extending beyond the sides, in the overlapping region 7 between the two stacked battery strings, isolating the two stacked battery strings from each other. Specifically, the edge of the first inner encapsulation film 31 is clamped by the edge of the two adjacent battery strings in the overlapping region 7. This design reduces stress in the overlapping region 7, preventing hidden cracks in the battery cells, and eliminates gaps between adjacent battery strings, reducing the non-power-generating area of ​​the module. Of course, in this embodiment, the battery strings can also be placed using other structures, and the battery strings can be fixed to the same plane instead of directly contacting each other. The placement structure of multiple battery strings is not specifically limited here. It should be noted that in this embodiment, it is necessary to additionally provide bus bars and other structures to achieve electrical connection between battery strings.

[0102] S206: The front cover plate, the interconnected battery strings and the back plate are laminated and packaged by an outer packaging film to form a laminate.

[0103] This step is basically the same as S103 in the above-mentioned embodiment of the invention. Please refer to the above-mentioned embodiment of the invention for details, and will not be described again here.

[0104] S207: The laminate is framed for edge protection and a terminal box is installed to manufacture a solar cell module.

[0105] In this step, a frame is formed around the laminate to provide edge protection, and a terminal box is installed to complete the solar cell module. The specific details of the edge protection and terminal box installation, as well as the specific structure of the devices involved, can be customized based on actual conditions and are not specifically limited here.

[0106] A method for manufacturing a solar cell module provided by an embodiment of the present invention achieves uniform and high-quality packaging through a total of two packaging processes: the first packaging connects the solder ribbon 2 to the cell 1 through an adhesive film, and the second packaging encapsulates the cell string. By increasing the amount of adhesive film in the cell gap, lamination bubbles caused by local adhesive deficiency of the low-flow adhesive film can be eliminated. The secondary packaging can achieve high-density packaging between the cell strings, thereby improving the efficiency of the photovoltaic module.

[0107] The present invention also provides a solar cell assembly, which is prepared using a solar cell assembly preparation method provided by any of the above-mentioned embodiments. The specific structures of the various components involved, including the inner encapsulation film layer, the outer encapsulation film layer, and the solar cell 1, have been described in detail in the above-mentioned embodiments.

[0108] A solar cell assembly provided by an embodiment of the present invention includes a cell string, an outer packaging film, a front cover plate and a back plate;

[0109] The battery string is formed by laying multiple battery cells 1 and welding ribbons 2 on a continuous inner packaging film 3, and the welding ribbons 2 are encapsulated on the surface of the battery cells 1 through the inner packaging film 3. The inner packaging film 3 is used to fix the welding ribbons 2 to the surface of the battery cells 1.

[0110] The plurality of battery strings are connected to each other, and the outer packaging film connects the front cover plate, the interconnected battery strings and the back plate to each other.

[0111] Optionally, in an embodiment of the present invention, the inner packaging film 3 includes a continuous first inner packaging film 31 and a second inner packaging film 32 corresponding to the battery cell;

[0112] The multiple battery cells 1 and welding ribbons 2 in the battery string are laid on the surface of the first inner packaging film 31 according to the preset battery string structure. The second inner packaging film 32 is laid on the surface of the battery cell 1 facing away from the first inner packaging film 31, and there are gaps between adjacent second inner packaging films 32.

[0113] Optionally, in an embodiment of the present invention, edges of adjacent battery strings are isolated from each other and stacked by an inner packaging film 3 extending beyond the sides of the battery, so that the battery strings are overlapped.

[0114] Optionally, in an embodiment of the present invention, edges of adjacent battery strings are isolated from each other and stacked by a first inner packaging film 31 extending beyond the side surfaces of the battery strings, so that the battery strings are overlapped.

[0115] Optionally, in an embodiment of the present invention, the edges of adjacent battery cells 1 in a battery string are isolated from each other and stacked by a second inner packaging film 32 extending beyond the sides of the battery cells 1 , so that the battery cells 1 are overlapped.

[0116] Optionally, in an embodiment of the present invention, a hollow structure 33 is provided in a non-encapsulation area of ​​the first inner packaging film 31 corresponding to the outer side of the welding ribbon 2 .

[0117] Optionally, in an embodiment of the present invention, a hollow structure 33 is provided in a non-encapsulation area of ​​the second inner packaging film 32 corresponding to the outer side of the welding ribbon 2 .

[0118] Optionally, in an embodiment of the present invention, the second inner packaging film 32 is a plurality of films covering the soldering tape 2 located on the surface of the battery cell 1 facing away from the bottom plate 4 .

[0119] Optionally, in an embodiment of the present invention, the battery cell 1 includes a busbar-less battery cell 1 , and the welding ribbon 2 is a low-temperature welding ribbon 2 .

[0120] Optionally, in an embodiment of the present invention, the fluidity of the outer packaging film is greater than that of the inner packaging film 3 .

[0121] Optionally, in an embodiment of the present invention, the laminate is a laminate with edge frame protection, and the laminate is connected to an end box.

[0122] Because the solar cell assembly provided in the embodiments of the present invention is manufactured based on the above-described solar cell assembly manufacturing method, the solar cell assembly has higher packaging quality and higher photovoltaic module efficiency. The specific details of each component have been described in detail in the above-described embodiments of the invention and will not be repeated here.

[0123] Please refer to Figures 9 to 15, Figure 9 is a schematic diagram of the top structure of the first package in the first solar cell module manufacturing method; Figure 10 is a schematic diagram of the top structure of the first package in the first solar cell module manufacturing method; Figure 11 is a schematic diagram of the top structure of the first package in the second solar cell module manufacturing method; Figure 12 is a schematic diagram of the top structure of the first package in the second solar cell module manufacturing method; Figure 13 is a schematic diagram of the top structure of the first package in the third solar cell module manufacturing method; Figure 14 is a schematic diagram of the top structure of the first package in the third solar cell module manufacturing method; Figure 15 is a schematic diagram of the top structure of the first package in the fourth solar cell module manufacturing method.

[0124] The present invention provides four specific embodiments. The difference between the following four specific embodiments mainly lies in the different structures of the packaging films.

[0125] Example 1

[0126] Referring to Figures 9 and 10, in this embodiment, the low-temperature solder tape is encapsulated on both sides of the battery cell 1 through the inner encapsulation film 3 to form a battery string; then the battery string is encapsulated by the outer encapsulation film, leaving only the lead-out terminal box, and other areas are not exposed to the air, and the outer side of the outer encapsulation film is the front glass and the back glass.

[0127] Among them, the battery cell 1 is a TOPCon battery, and the battery cell 1 is in contact with the welding ribbon 2 through laminated tin to the battery main grid pad and fine grid line; the melting point of the outer surface of the above-mentioned low-temperature welding ribbon is 90~137℃; the cross-linking degree of the above-mentioned inner layer packaging film 3 as a low-fluidity film is in the range of 10%~75%, and the thickness of the film is 100±10um; the above-mentioned outer layer packaging film is a combination of EVA and POE, such as using POE film on the front and EVA film on the back.

[0128] When preparing a battery string, a continuous first inner layer packaging film 31 is laid along a preset direction on a bottom plate 4 with a movable bottom and lower adsorption, and the low-temperature solder tape is pulled, the battery cell 1 is placed, the low-temperature solder tape is pulled, the second inner layer packaging film 32 is placed, and the press 6 is placed. The platform is moved to the heating source 42 for heating to form a weak package.

[0129] The length of the first inner encapsulation film 31 is slightly less than the length of the battery string, and the width direction exceeds the battery width by 10mm. The material of this film is EVA film. The second inner encapsulation film 32 is 5mm-10mm wide and extends along the direction of the soldering ribbon 2. The length is ±5mm of the battery string length. The strips of POE film covering the soldering ribbon 2 are multiple strips. The heating temperature of the base plate 4 is 100±30°C, and the pressure of the press 6 on the inner encapsulation film 3 is 0.1N / cm 2 ~100N / cm 2 .

[0130] During the secondary packaging, the battery strings obtained from the primary packaging are connected in series / parallel, with the spacing between adjacent strings being -1±1mm. The front POE film, the back EVA outer packaging film, the front glass, and the back panel are then stacked on the outside of the battery string array. The stacking is then performed by lamination to form a laminate, and finally the edges are framed for protection and the terminal box is installed. Referring to FIG7 , the edges of adjacent battery strings are isolated and stacked by an inner packaging film 3 extending beyond the sides of the battery, which is typically a first inner packaging film 31. That is, the edge portion of the first inner packaging film 31 is clamped by the edge portions of the two adjacent battery strings in the overlapping area 7. This design can reduce the stress in the overlapping area 7, avoid cracking of the battery cells 1, and eliminate the gaps between adjacent battery strings, reducing the non-power generation area of ​​the component. Similarly, adjacent battery cells 1 within a single battery string can be isolated and stacked by a second inner packaging film 32, improving the problem of cracking of the battery cells 1, eliminating the gaps between adjacent battery cells 1, and reducing the non-power generation area of ​​the component.

[0131] Example 2

[0132] Referring to Figures 11 and 12, in this embodiment, the low-temperature solder tape is encapsulated on both sides of the battery cell 1 through the inner encapsulation film 3 to form a battery string; then the battery string is encapsulated by the outer encapsulation film, leaving only the lead-out terminal box, and other areas are not exposed to the air, and the outer side of the outer encapsulation film is the front glass and the back glass.

[0133] The battery has an HJT structure and only includes fine-grid batteries without main grid lines; the melting point of the outer surface of the low-temperature solder tape is 90 to 137°C; the cross-linking degree of the inner layer packaging film 3 as a low-fluidity film is in the range of 10% to 75%, and the thickness of the film is 80±10um; the outer layer packaging film is a combination of EVA and POE, such as using POE film on the front and EVA film on the back.

[0134] When preparing a battery string, a continuous first inner layer packaging film 31 is laid along a preset direction on a bottom plate 4 with a movable bottom and lower adsorption, and the low-temperature solder tape is pulled, the battery cell 1 is placed, the low-temperature solder tape is pulled, the second inner layer packaging film 32 is placed, and the press 6 is placed. The platform is moved to the heating source 42 for heating to form a weak package.

[0135] The first inner packaging film 31 is a plurality of strips of film with a length slightly less than 5mm of the battery string length and a width of 2mm to 10mm. The material of the film is POE film. The second inner packaging film 32 is an EVA film with an internal hollow width of 5mm-10mm and a hole array of 10mm to 50mm along the preset direction in the length direction. The heating temperature of the bottom plate 4 is 80±30℃, and the pressure of the press 6 on the inner packaging film 3 is 0.1N / cm 2 ~100N / cm 2 .

[0136] During the secondary packaging, the battery strings obtained from the primary packaging will be connected in series / parallel, with the spacing between adjacent strings being 1±1mm. Then, the front EVA film, the back POE outer packaging film, the front glass, and the back panel are stacked on the outside of the battery string array, and then packaged by lamination to form a laminate. Finally, the edges are framed for protection and the terminal box is installed. The adjacent battery strings are isolated and stacked by the first inner packaging film 31 that extends beyond the side of the battery.

[0137] Example 3

[0138] Referring to Figures 13 and 14, in this embodiment, the low-temperature solder tape is encapsulated on both sides of the battery cell 1 through the inner encapsulation film 3 to form a battery string; then the battery string is encapsulated by the outer encapsulation film, leaving only the lead-out terminal box, and other areas are not exposed to the air, and the outer side of the outer encapsulation film is the front glass and the back glass.

[0139] The battery is of PERC structure, and only contains fine grid lines but no main grid lines; the melting point of the outer surface of the above-mentioned low-temperature solder tape is 90~137℃; the cross-linking degree of the above-mentioned inner layer packaging film 3 as a low-fluidity film is in the range of 10%~75%, and the thickness of the film is 80±10um; the above-mentioned outer layer packaging film is PVB film.

[0140] When preparing a battery string, a continuous first inner layer packaging film 31 is laid along a preset direction on a bottom plate 4 with a movable bottom and lower adsorption, and the low-temperature solder tape is pulled, the battery cell 1 is placed, the low-temperature solder tape is pulled, the second inner layer packaging film 32 is placed, and the press 6 is placed. The platform is moved to the heating source 42 for heating to form a weak package.

[0141] The first inner packaging film 31 is a mesh film with a length slightly smaller than the length of the battery string by 5mm and containing multiple parallel hollow areas with a width of 2mm to 10mm. The material of this film is PVB film. The second inner packaging film 32 is a serrated PVB film with a hollow width of 5mm to 10mm on one side. The heating temperature of the base plate 4 is 170±30℃, and the pressure of the press 6 on the inner packaging film 3 is 0.1N / cm 2 ~100N / cm 2 .

[0142] During the secondary packaging, the battery strings obtained from the primary packaging are connected in series / parallel, with the spacing between adjacent strings being 1±1mm. The front PVB film, the back PVB outer packaging film, the front glass, and the back panel are then stacked on the outside of the battery string array. The packaging is then performed by lamination to form a laminate. Finally, the edges are framed for protection and the terminal box is installed. The adjacent battery strings are isolated and stacked by the first inner packaging film 31 that extends beyond the side of the battery.

[0143] Example 4

[0144] Referring to Figure 15, in this embodiment, the low-temperature solder tape is encapsulated on both sides of the battery cell 1 through the inner encapsulation film 3 to form a battery string; then the battery string is encapsulated by the outer encapsulation film, leaving only the lead-out terminal box, and other areas are not exposed to the air, and the outer side of the outer encapsulation film is the front glass and the back glass.

[0145] The battery has a back-contact structure, including but not limited to a main grid-free battery; the melting point of the outer surface of the low-temperature solder tape is 90 to 137°C; the cross-linking degree of the inner layer packaging film 3 as the low-fluidity film is in the range of 10% to 75%, and the thickness of the film is 80±10um; the outer layer packaging film is an EVA film.

[0146] When preparing a battery string, a continuous first inner layer packaging film 31 is laid along a preset direction on a bottom plate 4 with a movable bottom and lower adsorption, and the low-temperature solder tape is pulled, the battery cell 1 is placed, the low-temperature solder tape is pulled, the second inner layer packaging film 32 is placed, and the press 6 is placed. The platform is moved to the heating source 42 for heating to form a weak package.

[0147] The second inner packaging film 32 is a plurality of parallel EVA films with a width of 5mm-10mm. The heating temperature of the bottom plate 4 is 70±30℃, and the pressure of the pressing tool 6 on the inner packaging film 3 is 0.1N / cm 2 ~100N / cm 2 .

[0148] During the secondary packaging, the battery strings obtained from the primary packaging will be connected in series / parallel, with the spacing between adjacent strings being 0.5±0.5mm. Then, the front EVA film, the back POE outer packaging film, the front glass, and the back panel are stacked on the outside of the battery string array, and then packaged by lamination to form a laminate. Finally, the edges are framed for protection and the terminal box is installed. The adjacent battery strings are isolated and stacked by the first inner packaging film 31 that extends beyond the side of the battery.

[0149] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from the other embodiments. Reference can be made to the descriptions of the identical or similar parts between the various embodiments. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple, and the relevant parts can be referred to the descriptions of the methods.

[0150] Professionals may further appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the above description has generally described the components and steps of each example according to their functions. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals and technicians may use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present invention.

[0151] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein may be implemented directly using hardware, a software module executed by a processor, or a combination of the two. The software module may be placed in a random access memory (RAM), internal memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, a hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art.

[0152] Finally, it should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the process, method, article, or device comprising the element.

[0153] The above describes in detail a method for manufacturing a solar cell module and a solar cell module provided by the present invention. Specific examples are used herein to illustrate the principles and implementation methods of the present invention. The description of the above examples is intended only to facilitate understanding of the method and core concepts of the present invention. It should be noted that those skilled in the art may make various improvements and modifications to the present invention without departing from the principles of the present invention, and such improvements and modifications fall within the scope of protection of the claims of the present invention.

Claims

1. A method for manufacturing a solar cell module, characterized in that: include: Laying a plurality of battery cells and welding strips on a continuous inner packaging film, and packaging the welding strips on the surface of the battery cells through the inner packaging film to form a battery string; the inner packaging film is used to fix the welding strips on the surface of the battery cells; connecting the battery strings to each other; The front cover plate, the interconnected battery strings and the back plate are laminated and packaged by an outer packaging film to form a laminate; the outer packaging film is located between the battery string and the front cover plate, and between the battery string and the back plate; The solar cell module is produced based on the laminate.

2. The method according to claim 1, characterized in that The step of laying a plurality of battery cells and welding strips on a continuous inner packaging film, and packaging the welding strips on the surface of the battery cells through the inner packaging film to form a battery string comprises: Laying a continuous first inner layer packaging film on the surface of the base plate; Laying welding strips and a plurality of battery cells on the surface of the first inner packaging film according to a preset battery string structure; The second inner packaging film corresponding to each of the battery cells is laid on the surface of the battery cell facing away from the bottom plate; the first inner packaging film and the second inner packaging film are both used to fix the welding tape to the surface of the battery cell; there are gaps between adjacent second inner packaging films; A press is placed on the surface of the second inner packaging film and heated to package the welding ribbon on the surface of the battery cell to form a battery string.

3. The method according to claim 2, characterized in that The bottom plate has an adsorption structure for adsorbing the first inner packaging film.

4. The method according to claim 3, characterized in that The first inner packaging film is provided with a hollow structure in a non-packaging area corresponding to the outer side of the welding strip, so that the adsorption structure can adsorb the battery cell through the hollow structure.

5. The method according to claim 4, characterized in that The second inner packaging film is provided with a hollow structure in a non-packaging area corresponding to the outer side of the welding strip.

6. The method according to claim 4, characterized in that The second inner packaging film is a plurality of films covering welding strips on the surface of the battery cell facing away from the bottom plate.

7. The method according to claim 1, characterized in that The battery cell comprises a main grid-free battery cell, and the welding strip is a low-temperature welding strip.

8. The method according to claim 1, characterized in that The outer packaging film has greater fluidity than the inner packaging film.

9. The method according to claim 1, characterized in that: The solar cell module is manufactured based on the laminate, comprising: The laminate is framed for edge protection and the lead-out terminal box is installed to manufacture the solar cell assembly.

10. The method according to claim 2, characterized in that Connecting the battery strings to each other comprises: The edges of adjacent battery strings are isolated and stacked with each other by the inner packaging film extending beyond the side surfaces of the battery sheets, so as to overlap the battery strings.

11. The method according to claim 10, characterized in that The edges of adjacent battery strings are isolated and stacked by an inner packaging film extending beyond the sides of the battery cells, so as to overlap the battery strings, including: The edges of adjacent battery strings are isolated and stacked with each other by a first inner layer packaging film extending beyond the side of the battery string, so as to overlap the battery strings.

12. The method according to claim 11, characterized in that Laying the second inner layer packaging film corresponding to each of the battery cells on the surface of the battery cell facing away from the bottom plate comprises: The edges of adjacent battery cells are isolated from each other and stacked by a second inner layer packaging adhesive film extending beyond the side surfaces of the battery cells, so as to overlap the battery cells.

13. A solar cell module, characterized in that: Including battery string, outer packaging film, front cover and back plate; The battery string is formed by laying a plurality of battery cells and welding strips on a continuous inner packaging film, and the welding strips are packaged on the surface of the battery cells through the inner packaging film; the inner packaging film is used to fix the welding strips on the surface of the battery cells; The plurality of battery strings are interconnected, and the outer packaging film connects the front cover plate, the interconnected battery strings and the back plate to each other.

14. The solar cell assembly according to claim 13, characterized in that: The inner packaging film includes a first inner packaging film that is continuous and has a second inner packaging film corresponding to the battery cell; The plurality of battery cells and welding strips in the battery string are laid on the surface of the first inner packaging film according to a preset battery string structure, the second inner packaging film is laid on the surface of the battery cells facing away from the first inner packaging film, and there are gaps between adjacent second inner packaging films.

15. The solar cell assembly according to claim 14, characterized in that: The edges of adjacent battery strings are isolated from each other and stacked by inner packaging films extending beyond the sides of the batteries, so that the battery strings are overlapped.

16. The solar cell assembly according to claim 15, characterized in that: The edges of adjacent battery strings are isolated from each other and stacked by a first inner layer packaging film extending beyond the side surfaces of the battery strings, so that the battery strings are overlapped.

17. The solar cell assembly according to claim 15, characterized in that: The edges of adjacent battery cells in the battery string are isolated from each other and stacked by a second inner layer packaging adhesive film extending beyond the sides of the battery cells, so that the battery cells are overlapped.

18. The solar cell assembly according to claim 14, characterized in that: It comprises a plurality of the second inner packaging films, and a plurality of welding strips are arranged on one surface of the battery cell; the second inner packaging films correspond one to one with the welding strips on one side of the battery cell, and the second inner packaging films encapsulate the corresponding welding strips on the surface of the battery cell.

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