A photovoltaic module and method of manufacturing the same

Abstract

The application relates to the technical field of solar cells, in particular to a photovoltaic module and a manufacturing method thereof. The photovoltaic module comprises a cell string group, a second bus bar and a connecting part. The second bus bar is located on one side or both sides of the cell string group, and in a third direction, the second bus bar is located on the back light surface of the cell string group, and the second bus bar partially overlaps the cell piece, so that the total size of the second bus bar and the cell string in the first direction can be reduced, the arrangement space of the second bus bar and the cell string is reduced, more cell pieces can be arranged in the limited space, the screen ratio of the photovoltaic module is improved, and the output power of the photovoltaic module is improved. The second bus bar and the string welding strip are electrically connected through the connecting part, the risk of breakage and damage caused by the bending of the edge welding strip, the cracking of the welding spot and the like is reduced, the risk of hidden cracking caused by the local increase of the thickness of the cell layer during the laminating process is also reduced, and the processing yield and the working stability of the photovoltaic module are improved.

Description

[0001] This application is a divisional application. The original application has the application number 202511612059.0 and the filing date is November 5, 2025. The entire contents of the original application are incorporated herein by reference. Technical Field

[0002] This application relates to the field of solar cell technology, and more particularly to a photovoltaic module and its manufacturing method. Background Technology

[0003] A photovoltaic module includes multiple cell strings, each cell string contains multiple cells, the multiple cell strings are arranged along a first direction and electrically connected to form a cell string group, the multiple cell string groups are arranged along a second direction, and the extension direction of the cell string group is denoted as the first direction, then the first direction and the second direction intersect.

[0004] The photovoltaic module also includes a busbar extending along a second direction. The busbar is located on one or both sides of the battery string in the first direction. The busbar is electrically connected to the adjacent battery string to realize the series or parallel connection of the adjacent battery string.

[0005] Normally, the busbar is located on the outside of the battery string in the first direction, that is, there is a gap between the busbar and the adjacent battery cell in the first direction. The solder strip on the battery string extends outward along the first direction and is welded and fixed to the busbar.

[0006] However, the aforementioned gaps result in a large arrangement space for busbars and battery strings. In order to meet the arrangement space of the busbars, the number of battery strings needs to be sacrificed, which affects the output power of the photovoltaic modules.

[0007] Therefore, how to reduce the arrangement space of busbars and battery strings to improve the output power of photovoltaic modules is an important problem that needs to be solved in this field. Summary of the Invention

[0008] In view of this, this application provides a photovoltaic module and a method for manufacturing the same, which can reduce the arrangement space of busbars and battery strings to improve the output power of the photovoltaic module.

[0009] This application provides a photovoltaic module, which includes a battery string assembly, a second busbar, and a connecting portion. The battery string assembly includes at least two battery strings arranged along a first direction, each battery string comprising multiple solar cells and string bonding strips. The multiple battery string assemblies are arranged along a second direction, where the first and second directions intersect. In the first direction, the second busbar is located on one or both sides of the battery string assembly. In a third direction, the connecting portion is located on the side of the second busbar facing the solar cells. The second busbar and the string bonding strips are electrically connected via the connecting portion, and adjacent battery string assemblies are electrically connected via the second busbar. The second busbar is located on the back surface of the battery string assembly, and in a third direction, the second busbar partially overlaps with the solar cells.

[0010] In some possible designs, the connecting part is welded to the second busbar or hot-pressed to fix it. Alternatively, the second busbar and the connecting part are integrally formed.

[0011] In some possible designs, the second busbar includes a first edge and a second edge arranged along a first direction, wherein the first edge is located on the side of the second busbar facing the battery string, and the second edge is located on the side of the second busbar away from the battery string. In a third direction, the edge of the connector is aligned with the second edge.

[0012] In some possible designs, in the first direction, the width of the second busbar is H1, and the width of the connector is H2, where 1.3 < H1 / H2 ≤ 75. In the second direction, the length of the connector is less than the length of the second busbar.

[0013] In some possible designs, in the second direction, there is a gap between the end of the connector and the end of the second busbar, and the size of the gap in the second direction is H3, 20mm≤H3≤50mm, or 0mm≤H3≤5mm.

[0014] In some possible designs, the stringing strip includes an edge strip, which comprises a first body and a second body arranged along a first direction. The first body is electrically connected to the solar cell, and the second body is electrically connected to the connecting portion. In the second direction, the width of the second body is greater than the width of the first body.

[0015] In some possible designs, the thickness of the second body is less than the thickness of the first body in the third direction.

[0016] In some possible designs, the edge solder strip is located on either the light-facing or back-facing side of the solar cell. When the edge solder strip is located on the light-facing side of the solar cell, in the third direction, the distance between the light-facing side of the first body and the back-facing side of the solar cell is L1, the distance between the light-facing side of the second busbar and the back-facing side of the solar cell is L2, and the thickness of the connection is L3, where L2 ≤ L3 < L1, or L2 < L3 ≤ L1. When the edge solder strip is located on the back-facing side of the solar cell, in the third direction, the distance between the light-facing side of the first body and the light-facing side of the second busbar is L4, the distance between the back-facing side of the first body and the light-facing side of the second busbar is L5, and the thickness of the connection is L6, where L5 ≤ L6 < L4, or L5 < L6 ≤ L4.

[0017] In some possible designs, in the first direction, the connecting part and the edge of the battery cell are left with a preset distance, which is less than or equal to 1.5mm.

[0018] In some possible designs, the cross-sectional shape of the connection is rectangular.

[0019] In some possible designs, the photovoltaic module also includes an insulating strip, which, in the third direction, is located between the second busbar and the solar cell.

[0020] In some possible designs, in the first direction, the insulating strip extends to the outside of the cell in the direction toward the connection.

[0021] In some possible designs, the insulating strip contacts the connecting part in the first direction, or there is a gap between the insulating strip and the connecting part.

[0022] In some possible designs, there is one insulating strip in the second direction. Alternatively, there are multiple insulating strips in the second direction, with each insulating strip corresponding to a battery string. Or, there are multiple insulating strips in the second direction, with one insulating strip connected to at least two battery strings.

[0023] A second aspect of this application provides a method for manufacturing a photovoltaic module, the method comprising: Prepare a battery string assembly, which includes at least two battery strings arranged along a first direction, and the battery strings include multiple battery cells and string bonding strips.

[0024] Multiple battery strings are arranged along the second direction, where the first and second directions intersect.

[0025] In the first direction, the connector is placed on one or both sides of the battery string assembly, and the connector extends along the second direction. In the third direction, the connector is located on the back surface of the battery string assembly. The connector is then welded and fixed to the string welding strip.

[0026] An encapsulation layer and a cover plate are laid on the light-facing and back-facing sides of the battery string, and then laminated to form a laminate.

[0027] A frame is installed at the edge of the laminate to form a photovoltaic module.

[0028] Before or after placing the connector on one or both sides of the battery string, the photovoltaic module manufacturing method further includes: welding the connector to a second busbar; after welding the connector to the string strip, the second busbar is located on the back surface of the battery string, and in the third direction, the second busbar partially overlaps with the battery cell.

[0029] In some possible designs, the stringing ribbon includes edge strips. Prior to the step of fabricating the cell strings, the manufacturing method of the photovoltaic module includes: The ends of the edge solder strips are flattened to form the second body.

[0030] The steps of welding and fixing the connecting part to the welding strip include:

[0031] The connecting part is welded and fixed to the second body.

[0032] In some possible designs, the steps for fabricating battery string groups include: Multiple solar cells are arranged along the first direction.

[0033] The wire bonding strip is placed on the battery cell and welded to form a battery string.

[0034] Arrange at least two battery strings along the first direction.

[0035] The string welding strips of adjacent battery strings are welded together to form a battery string group.

[0036] In some possible designs, the stringing ribbon includes a first ribbon and a second ribbon, and the steps for fabricating the battery string include: Multiple solar cells are arranged along the first direction.

[0037] The first solder strip is placed on the battery cell and welded to form a battery string.

[0038] Arrange at least two battery strings along the first direction.

[0039] In the first direction, the two ends of the second welding strip are placed on adjacent battery strings and welded to form a battery string group.

[0040] In some possible designs, prior to the step of arranging at least two cell strings along a first direction, the method of manufacturing the photovoltaic module further includes: Place the insulating strip on the battery string, with the third side facing upwards and the insulating strip located on the back side of the battery cell.

[0041] The insulating strip is fixed to the battery string by hot stamping.

[0042] In some possible designs, the manufacturing method of photovoltaic modules further includes, prior to the step of welding the connectors to the string strips: Place the insulating strip on the battery string, with the third side facing upwards and the insulating strip located on the back side of the battery cell.

[0043] The insulating strip is fixed to the battery string using a hot-spinning process.

[0044] In this application, the second busbar is located on the back surface of the solar cell, so that part of the structure of the second busbar is blocked by the solar cell. Without adjusting the size of the solar cell and the second busbar in the first direction, the total size of the second busbar and the solar cell string in the first direction can be reduced, thereby reducing the arrangement space of the second busbar and the solar cell string. This allows for the arrangement of more solar cells in a limited space, thereby increasing the screen ratio of the photovoltaic module and improving the output power of the photovoltaic module.

[0045] The second busbar is electrically connected to the edge solder strip through a connection extending in the third direction, which reduces the risk of edge solder strip bending and breaking, solder joint cracking, etc. It also reduces the risk of hidden cracks in the lamination process caused by local increase in the thickness of the battery layer, thereby improving the processing yield and working stability of photovoltaic modules.

[0046] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. Attached Figure Description

[0047] To more clearly illustrate the technical solutions of the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 The photovoltaic module provided in this application is shown in some embodiments as a structural cross-sectional view. Figure 2 This is a partial structural diagram of the battery layer in some embodiments; Figure 3 This is a top view of the battery layer in some embodiments; Figure 4 for Figure 3 An enlarged view of part A in the image; Figure 5 for Figure 3 An enlarged view of part B in the image; Figure 6A cross-sectional view of the connection structure between the first busbar and the battery string in the related technology; Figure 7 A cross-sectional view of the connection structure between the second busbar and the battery string provided in this application in a first embodiment; Figure 8 for Figure 6 A schematic diagram of the structure in which the first busbar is folded to the back surface of the solar cell; Figure 9 This is a top view of the connection structure between the second busbar and the connecting part; Figure 10 A top view of the connection structure between the connector and the edge weld strip from a third-party perspective; Figure 11 This is a schematic diagram of a partial structure of the edge solder strip; Figure 12 A cross-sectional view of the connection structure between the second busbar and the battery string provided in this application in a second embodiment; Figure 13 This is a cross-sectional view of the insulating strip in some embodiments; Figure 14 A bottom view of the connection structure between the insulating strip and the battery cell in the edge region in some embodiments; Figure 15 A bottom view of the connection structure between the insulating strip and the battery cell in the edge region in some other embodiments; Figure 16 A bottom view of the connection structure between the insulating strip and the edge region of the battery cell in some other embodiments; Figure 17 A cross-sectional view of the connection structure between the second busbar and the battery string provided in this application in a third embodiment; Figure 18 A cross-sectional view of the connection structure between the second busbar and the battery string provided in this application in the fourth embodiment; Figure 19 A flowchart of the photovoltaic module manufacturing method provided in this application in the first embodiment; Figure 20 A flowchart of the photovoltaic module manufacturing method provided in this application in a second embodiment; Figure 21 A flowchart of some steps in some embodiments of the photovoltaic module manufacturing method provided in this application; Figure 22 This is a schematic diagram of the battery string assembly in the first embodiment; Figure 23 Here is a flowchart of step A1 in some embodiments; Figure 24 This is a schematic diagram of the battery string assembly in the second embodiment; Figure 25 Here is a flowchart of step A1 in some other embodiments; Figure 26 This is a flowchart illustrating the connection between the insulating strip and the battery string in some embodiments; Figure 27 This is a flowchart illustrating the connection between the insulating strip and the battery string in some other embodiments; Figure 28 A cross-sectional view of the connection structure between the first interconnecting bar and the battery string in the related technology; Figure 29 Cross-sectional views of the connection structure between the second interconnecting bar and the battery string provided in this application in some embodiments; Figure 30 for Figure 28 A schematic diagram of the structure in which the first interconnecting strip is folded to the back surface of the battery cell; Figure 31 A top view of the connection structure between the second interconnecting bar and the interconnecting part from a third-party perspective; Figure 32 A top view of the connection structure between the interconnection section and the electrical connector from a third-party perspective; Figure 33 This is a partial structural schematic diagram of an electrical connector in some embodiments; Figure 34 This is a top view of the electrical connector in some other embodiments; Figure 35 This is a partial structural schematic diagram of the electrical connector in some further embodiments; Figure 36 Cross-sectional view of the connection structure between the second interconnecting bar and the battery string in some other embodiments; Figure 37 This is a sectional view of the isolation component; Figure 38 A bottom view of the connection structure between the separator and the first end battery cell in some embodiments; Figure 39 A bottom view of the connection structure between the separator and the first end battery cell in some other embodiments; Figure 40 A bottom view of the connection structure between the separator and the first end battery cell in some other embodiments; Figure 41 A cross-sectional view of the middle region of the battery string in one embodiment; Figure 42 A cross-sectional view of the middle region of the battery string in another embodiment; Figure 43 A flowchart of the photovoltaic module manufacturing method provided in this application in a third embodiment; Figure 44A flowchart of the photovoltaic module manufacturing method provided in this application in the fourth embodiment; Figure 45 A flowchart of part of step S1 in the first embodiment; Figure 46 for Figure 45 The steps in this process are shown in flowcharts in some embodiments; Figure 47 This is a flowchart of part of step S1 in the second embodiment; Figure 48 for Figure 47 The steps in this process are shown in flowcharts in some embodiments; Figure 49 A flowchart of part of step S1 in the third embodiment; Figure 50 This is a flowchart of part of step S1 in the fourth embodiment.

[0049] Figure label: 10-Cover plate; 101-First cover plate; 102-Second cover plate; 20 - Encapsulation layer; 201 - First adhesive film; 202 - Second adhesive film; 30-Battery layer; 301-Battery cell; 3011-First end battery cell; 3012-Second end battery cell; 302-Series welding strip; 3021-First welding strip; 3022-Second welding strip; 303-Battery string; 3031-First battery string; 3032-Second battery string; 304-Bus unit; 305-Battery string assembly; 1-Busbar; 11-First busbar; 111-First gap; 12-Second busbar; 121-First edge; 122-Second edge; 13-Connecting part; 2-Interconnecting bar; 21-First interconnecting bar; 211-Second gap; 22-Second interconnecting bar; 23-Interconnecting section; 3-Edge solder strip; 31-First body; 32-Second body; 4-Electrical connector; 41-Electrical connector body; 411-First electrical connector body; 412-Second electrical connector body; 42-Electrical connector part; 421-First connecting section; 422-Second connecting section; 43-First electrical connector; 44-Second electrical connector; 5-Insulating strip; 51-First layer; 52-Second layer; 53-Third layer; 6-Isolation element; 61-First isolation layer; 62-Second isolation layer; 63-Third isolation layer. Detailed Implementation

[0050] To better understand the technical solution of this application, the embodiments of this application will be described in detail below with reference to the accompanying drawings.

[0051] It should be understood that the described embodiments are merely some, not all, of the embodiments in this application. All other embodiments obtained by those skilled in the art based on the embodiments in this application without inventive effort are within the scope of protection of this application.

[0052] The terminology used in the embodiments of this application is for the purpose of describing particular embodiments only and is not intended to be limiting of this application. The singular forms “a,” “the,” and “the” used in the embodiments of this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise.

[0053] It should be understood that the term "and / or" used in this article is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, the character " / " in this article generally indicates that the preceding and following related objects have an "or" relationship.

[0054] The first aspect of this application provides a photovoltaic module, Figure 1 The structural cross-sectional views of the photovoltaic module provided in this application in some embodiments are as follows: Figure 1 As shown, the photovoltaic module includes a cover plate 10, an encapsulation layer 20, and a cell layer 30.

[0055] The cover plate 10 includes a first cover plate 101 and a second cover plate 102 arranged along the third direction Z. The encapsulation layer 20 and the battery layer 30 are located between the first cover plate 101 and the second cover plate 102. A portion of the encapsulation layer 20 is located between the battery layer 30 and the first cover plate 101, and another portion of the encapsulation layer 20 is located between the battery layer 30 and the second cover plate 102, so as to achieve the encapsulation and fixation of the cover plate 10 and the battery layer 30.

[0056] At least one of the first cover plate 101 and the second cover plate 102 is made of a light-transmitting material, which is beneficial to improving the photoelectric conversion efficiency of the photovoltaic module.

[0057] The first cover plate 101 can be made of one of the following rigid materials: tempered glass, PET (polyethylene terephthalate), or PC (polycarbonate). Alternatively, the first cover plate 101 can be made of one of the following flexible materials: PVF (polyvinyl fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), or PVDF (polyvinylidene fluoride). All of these materials have high light transmittance, ensuring that more light reaches the battery layer, thereby increasing the light absorption of the photovoltaic module and improving its photoelectric conversion efficiency.

[0058] The material of the second cover plate 102 can be one of rigid materials such as tempered glass, PET (polyethylene terephthalate), or PC (polycarbonate). Alternatively, the material of the second cover plate 102 can be one of flexible materials such as PVF (polyvinyl fluoride), ETFE (ethylene-tetrafluoroethylene copolymer), or PVDF (polyvinylidene fluoride).

[0059] The materials of the first cover plate 101 and the second cover plate 102 can be the same or different.

[0060] like Figure 22 As shown, the encapsulation layer 20 includes a first adhesive film 201 and a second adhesive film 202. In the third direction Z, a portion of the structure of the first adhesive film 201 is located between the battery layer 30 and the first cover plate 101, and a portion of the structure of the second adhesive film 202 is located between the battery layer and the second cover plate 102.

[0061] The first encapsulant film 201 is made of one of the following polyolefins: EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), or PVB (Polyvinyl Butyral). These materials have high light transmittance, which is beneficial for improving the photoelectric conversion efficiency of photovoltaic modules. The first encapsulant film 201 can also be an EPE film (EVA-POE-EVA co-extrusion structure) or an EP film (EVA-POE co-extrusion structure).

[0062] The material of the second film 202 is one of polyolefins such as EVA (Ethylene-Vinyl Acetate Copolymer), POE (Polyolefin Elastomer), and PVB (Polyvinyl Butyral). The second film 202 can also be an EPE film (EVA-POE-EVA co-extrusion structure) or an EP film (EVA-POE co-extrusion structure).

[0063] The materials of the first adhesive film 201 and the second adhesive film 202 can be the same or different.

[0064] Figure 2 This is a partial structural diagram of the battery layer in some embodiments. For example... Figure 2 As shown, the battery layer 30 includes a plurality of battery cells 301. In the first direction X, adjacent battery cells 301 are electrically connected by a wire bonding strip 302 to form a battery string 303. The thickness direction of the battery cells 301 is parallel to the aforementioned third direction Z.

[0065] Figure 3 This is a top view of the battery layer in some embodiments. (e.g.) Figure 3 As shown, in the first direction X and / or the second direction Y, adjacent battery strings 303 are electrically connected by a busbar 304. The busbar 304 is used to realize the series or parallel connection between adjacent battery strings 303. The thickness direction of the battery string 303 is parallel to the aforementioned third direction Z, and the first direction X, the second direction Y and the third direction Z intersect each other.

[0066] In the first direction X, the spacing between adjacent battery cells 301 is -1mm to 2mm. For example, the spacing between adjacent battery cells 301 can be -1mm, -0.5mm, 0mm, 0.5mm, 1mm, 1.5mm, 2mm, etc.

[0067] For example, the spacing between adjacent solar cells is -1mm to 0mm, and the spacing between adjacent solar cells can be -1mm, -0.9mm, -0.8mm, -0.7mm, -0.6mm, -0.5mm, -0.4mm, -0.3mm, -0.2mm, -0.1mm, 0mm, etc.

[0068] For example, the spacing between adjacent solar cells is 0mm to 2mm, and the spacing between adjacent solar cells can be 0mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm, etc.

[0069] In the first direction X, the spacing between adjacent solar cells 301 is -0.3mm to 2mm. For example, the spacing between adjacent solar cells 301 can be -0.3mm, -0.2mm, -0.1mm, 0mm, 0.2mm, 0.4mm, 0.6mm, 0.8mm, 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm, etc.

[0070] In this embodiment, the spacing between adjacent solar cells 301 is -0.3mm to 2mm, which can reduce the area of ​​blank areas on the photovoltaic module. Blank areas refer to areas where no solar cells are installed and photoelectric conversion cannot be performed. Reducing the area of ​​blank areas can increase the proportion of the light-emitting area of ​​the photovoltaic module, thereby increasing the output power per unit area of ​​the photovoltaic module and improving the performance of the photovoltaic module.

[0071] For example, the spacing between adjacent solar cells is -0.3mm to 0mm, and the spacing between adjacent solar cells can be -0.3mm, -0.29mm, -0.28mm, -0.27mm, -0.26mm, -0.25mm, -0.24mm, -0.23mm, -0.22mm, -0.21mm, -0.2mm, -0.19mm, -0.18mm, -0.17mm, -0.16mm, -0.15mm, -0.14mm, -0.13mm, -0.12mm, -0.11mm, -0.1mm, -0.09mm, -0.08mm, -0.07mm, -0.06mm, -0.05mm, -0.04mm, -0.03mm, -0.02mm, -0.01mm, 0mm, etc.

[0072] For example, the spacing between adjacent solar cells is 0mm to 1mm, and the spacing between adjacent solar cells can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0073] For example, the spacing between adjacent solar cells is 1mm to 2mm, and the spacing between adjacent solar cells can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc.

[0074] In the first direction X, the spacing between adjacent battery strings 303 is 0.3mm to 6mm. For example, the spacing between adjacent battery strings 303 can be 0.3mm, 0.5mm, 0.7mm, 0.9mm, 1mm, 2mm, 3mm, 4mm, 5mm, 6mm, etc.

[0075] For example, the spacing between adjacent battery strings is 0.3mm to 2mm, and the spacing between adjacent battery strings 303 can be 0.3mm, 0.5mm, 1mm, 1.3mm, 1.5mm, 1.7mm, 1.9mm, 2mm, etc.

[0076] For example, the spacing between adjacent battery strings is 0.3mm to 1mm, and the spacing between adjacent battery strings 303 can be 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, 0.85mm, 0.9mm, 0.95mm, 1mm, etc.

[0077] For example, the spacing between adjacent battery strings is 1mm to 2mm, and the spacing between adjacent battery strings 303 can be 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, etc.

[0078] For example, the spacing between adjacent battery strings is 2mm to 4mm, and the spacing between adjacent battery strings can be 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm, 4mm, etc.

[0079] For example, the spacing between adjacent battery strings is 4mm to 6mm, and the spacing between adjacent battery strings can be 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, etc.

[0080] The types of solar cells include, but are not limited to, PaWWivated Emitter RearCell (PERC), Tunnel Oxide PaWWivated Contact (TOPCon), Intrinsic Thin-Film Heterojunction (HJT), and perovskite solar cells.

[0081] For PERC cells, along their thickness direction, the PERC cell sequentially includes a front surface silver electrode, a front surface silicon nitride passivation layer, a phosphorus emitter layer, a P-type substrate silicon layer, a local aluminum back field, a metallic aluminum back electrode, and a back passivation layer (Al2O3 / WiNx). PERC cells use a passivation film to passivate the back surface, replacing the all-aluminum back field, enhancing light reflection within the silicon substrate, reducing the recombination rate on the back surface, and improving the cell efficiency by 0.5%-1%.

[0082] For a TOPCon cell, along its thickness direction, it sequentially comprises a silver electrode, a front-surface silicon nitride passivation layer, a boron-doped emitter, an N-type substrate silicon layer, a diffused doped layer, an ultrathin silicon oxide layer, doped polycrystalline silicon, silicon nitride, and a silver electrode. The back of the cell consists of an ultrathin silicon oxide layer (1nm~2nm) and a phosphorus-doped microcrystalline-amorphous hybrid Wi film, which together form a passivation contact structure. This structure blocks minority carrier recombination, increasing the cell's open-circuit voltage and short-circuit current. The ultrathin oxide layer allows majority carrier electrons to tunnel into the polycrystalline silicon layer while blocking minority carrier recombination. The excellent passivation effect of the ultrathin silicon oxide and heavily doped silicon film causes band bending on the silicon wafer surface, creating a field passivation effect. This significantly increases the probability of electron tunneling, reduces contact resistance, and improves the cell's open-circuit voltage and short-circuit current, thereby increasing the cell's conversion efficiency.

[0083] For an HJT cell, along its thickness direction, the HJT cell sequentially includes a front low-temperature silver electrode, a front conductive film, an N-type amorphous silicon film, an intrinsic amorphous silicon film, an N-type substrate silicon layer, an intrinsic amorphous silicon film, a P-type amorphous silicon film, a back conductive film, and a back low-temperature silver electrode.

[0084] For a perovskite solar cell, along its thickness direction, it sequentially comprises a substrate material, a conductive thin film, an electron transport layer (titanium dioxide), a perovskite absorption layer (hole transport layer), and a metal cathode. Perovskite materials possess a high light absorption coefficient and a long carrier diffusion distance. After the photons absorbed by the perovskite material are converted into electrons, they are easily collected by the electrodes with minimal loss, thus generating high photogenerated voltage and current, resulting in high photoelectric conversion efficiency.

[0085] The following discussion uses TOPCon batteries as an example to illustrate the specific structure of battery cells.

[0086] Figure 4 for Figure 3 An enlarged view of part A in the image. (See image for example.) Figure 3 and Figure 4As shown, in the first direction X, the busbar 304 includes a busbar 1 located at the outermost edge of the battery layer, that is, the battery layer is provided with a busbar 1 on one or both sides in the first direction X. The string bonding strip 302 includes an edge bonding strip 3 located at the outermost edge of the battery layer. One end of the edge bonding strip 3 is electrically connected to the outermost battery cell 301, and the other end of the edge bonding strip 3 extends outward and is electrically connected to the busbar 1.

[0087] When the solar cell 301 is a TOPCon cell, both the light-facing and back-facing surfaces of the solar cell 301 are connected to a series welding strip 302.

[0088] Figure 5 for Figure 3 An enlarged view of part B in the image. (See image for example.) Figure 3 and Figure 5 As shown, in the first direction X, the busbar 304 includes an interconnecting strip 2 located between adjacent battery strings 303, and the stringing strip 302 includes an electrical connector 4. The two ends of the electrical connector 4 are electrically connected to the battery cells 301 on the adjacent battery strings 303, so that the adjacent battery strings 303 are connected in series or in parallel to form a battery string group 305. Multiple battery string groups 305 are arranged along the second direction Y. In the second direction Y, at least two battery string groups 305 are electrically connected to the same interconnecting strip 2, so that the adjacent battery string groups 305 are connected in series or in parallel.

[0089] The cross-sectional shape of the 302 wire strip can be circular or rectangular.

[0090] When the cross-sectional shape of the welding strip 302 is circular, the welding strip 302 is a circular welding strip, and the diameter of the welding strip 302 is 0.2mm~0.35mm. For example, the diameter of the welding strip 302 can be 0.2mm, 0.21mm, 0.23mm, 0.25mm, 0.27mm, 0.29mm, 0.3mm, 0.31mm, 0.35mm, etc.

[0091] For example, the diameter of the wire strip 302 is 0.2mm~0.3mm, and the diameter of the wire strip 302 can be 0.2mm, 0.21mm, 0.22mm, 0.23mm, 0.24mm, 0.25mm, 0.26mm, 0.27mm, 0.28mm, 0.29mm, 0.3mm, etc.

[0092] For example, the diameter of the wire strip 302 is 0.3mm to 0.35mm, and the diameter of the wire strip 302 can be 0.3mm, 0.31mm, 0.32mm, 0.33mm, 0.34mm, 0.35mm, etc.

[0093] Will Figure 4 The side where the busbar 1 is located is designated as the edge region of the battery layer 30. Figure 5 The side where the interconnecting strip 2 is located is designated as the middle region of the battery layer 30. The connection structure of the edge region and the middle region will be discussed below.

[0094] First, the connection structure of the edge region will be discussed in detail.

[0095] Figure 6 This is a cross-sectional view of the connection structure between the busbar and the battery string in related technologies. (Example) Figure 6 As shown, the busbar 1 in the related technology is referred to as the first busbar 11. The first busbar 11 and the adjacent battery cell 301 have a first gap 111 in the first direction X. The first gap 111 results in a large arrangement space for the first busbar 11 and the battery string 303. In order to meet the arrangement space of the first busbar 11 in a limited space, the number of battery strings 303 needs to be sacrificed, which affects the output power of the photovoltaic module.

[0096] Therefore, in order to reduce the arrangement space of busbar 1 and battery string 303, Figure 7 The connection structure between the busbar and the battery string provided in the embodiments of this application is shown in cross-sectional views in some embodiments. For example... Figure 7 As shown, the busbar 1 in this embodiment is referred to as the second busbar 12. The busbar 304 also includes a connecting portion 13. In the third direction Z, the connecting portion 13 is located on the side of the second busbar 12 facing the battery cell 301. The second busbar 12 and the edge solder strip 3 are electrically connected through the connecting portion 13, so that adjacent battery strings are electrically connected through the second busbar 12. The second busbar 12 is located on the back surface of the battery string, that is, in the third direction Z, a part of the structure of the second busbar 12 is located on the back surface of the battery cell 301, so that the projection of the second busbar 12 in the third direction Z overlaps with the projection of the battery cell in the third direction Z.

[0097] In this embodiment, the second busbar 12 is located on the back surface of the solar cell 301, so that a part of the structure of the second busbar 12 is blocked by the solar cell 301. Without adjusting the size of the solar cell 301 and the second busbar 12 in the first direction X, the total size of the second busbar 12 and the solar cell string 303 in the first direction X can be reduced, thereby reducing the arrangement space of the second busbar 12 and the solar cell string 303, so as to arrange more solar cells 301 in a limited space, thereby increasing the screen ratio of the photovoltaic module and improving the output power of the photovoltaic module.

[0098] based on Figure 6 According to the related technology shown, if the first busbar 11 is to be placed on the backlight surface of the battery cell, the first busbar 11 needs to be folded, and the structure after folding is as follows: Figure 8As shown, at this time, a portion of the edge solder strip 3 is folded onto the back surface of the battery cell 301 along with the first busbar 11. At the first busbar 11, the total thickness of the battery layer 30 is the thickness of the edge solder strip 3 on the light-facing side, the thickness of the battery cell 301, the thickness of the first busbar 11, and the thickness of the edge solder strip 3 on the back surface. This results in a localized increase in the thickness of the battery layer 30, which increases the risk of microcracks during subsequent lamination. Simultaneously, the folding of the edge solder strip 3 can lead to breakage and damage, also increasing the risk of solder joint cracking.

[0099] Therefore, as Figure 7 As shown, in this embodiment, the second busbar 12 and the edge solder strip 3 are electrically connected by a connecting portion 13 extending along the third direction Z, which reduces the risk of the edge solder strip 3 bending and breaking, and the risk of solder joint cracking. It also reduces the risk of local increase in the thickness of the battery layer 30 leading to hidden cracks in the lamination process, thereby improving the processing yield and working stability of the photovoltaic module.

[0100] The second busbar 12 and the connecting part 13 can be integrally formed to simplify the connection and shorten the connection cycle.

[0101] Alternatively, the second busbar 12 and the connecting part 13 can be separate structures, and the second busbar 12 and the connecting part 13 can be fixedly connected by welding or hot pressing to reduce the processing difficulty of the second busbar 12 and the connecting part 13 and shorten the processing cycle. In this case, the connecting part 13 can be a welding strip, and the cross-sectional shape of the connecting part 13 can be circular or rectangular, that is, the connecting part 13 can be a round welding strip or a flat welding strip.

[0102] The connecting part 13 and the edge welding strip 3 are fixedly connected by welding or hot pressing to reduce the processing difficulty of the connecting part 13 and the edge welding strip 3 and shorten the processing cycle.

[0103] like Figure 7 As shown, the second busbar 12 includes a first edge 121 and a second edge 122 arranged along a first direction X. In the first direction X, the first edge 121 is located on the side of the second busbar 12 facing the battery string 305, and the second edge 122 is located on the side of the second busbar 12 away from the battery string 305. In the third direction Z, the edge of the connecting portion 13 is aligned with the second edge 122.

[0104] In this embodiment, the outer edge of the connecting portion 13 is aligned with the outer edge of the second busbar 12, leaving a gap between the connecting portion 13 and the solar cell 301 in the first direction X. This reduces the risk of short circuit in the solar cell 301 due to direct contact between the connecting portion 13 and the solar cell 301. Furthermore, aligning the outer edge of the connecting portion 13 with the outer edge of the second busbar 12, while maintaining the gap between the connecting portion 13 and the solar cell 301 in the first direction X, allows for a reduction in the overall size of the connecting portion 13, the second busbar 12, and the solar cell string 303 in the first direction X. This facilitates increasing the size of the solar cell 301 within a limited space, thereby enhancing the output power of the photovoltaic module.

[0105] like Figure 7 As shown, in the first direction X, the width of the second busbar 12 is H1, and the width of the connecting part 13 is H2, where 1.3 < H1 / H2 ≤ 75. For example, H1 / H2 can be equal to 1.31, 1.5, 1.7, 2, 2.7, 3, 3.7, 4, 4.7, 5, 5.7, 6, 6.7, 7, 7.7, 8, 8.7, 9, 9.7, 10, 10.7, 11, 11.7, 12, 12.7, 13, 13.7, 14, 14.7, 15, 15.7, 16, 16.6, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, etc.

[0106] If the value of H1 / H2 is small, the width difference between the second busbar 12 and the connecting part 13 is small, and the risk of the connecting part 13 contacting the battery cell 301 and causing the battery cell 301 to short circuit is high.

[0107] If the ratio of H1 / H2 is large, the width of the second busbar 12 will be large, resulting in a higher material cost for the second busbar 12. Alternatively, if the width of the connecting part 13 is small, the current transmission capacity of the connecting part 13 will be poor, which will also result in poor connection stability between the connecting part 13 and the edge solder strip 3.

[0108] Therefore, in this embodiment, 1.3 < H1 / H2 ≤ 75 can increase the width difference between the second busbar 12 and the connecting portion 13, thereby reducing the risk of short circuit of the battery cell 301 caused by the contact between the connecting portion 13 and the battery cell 301. At the same time, it can also reduce the width of the second busbar 12, reduce the material cost of the second busbar 12, and increase the width of the connecting portion 13, thereby improving the current transmission capacity of the connecting portion 13 and the connection stability between the connecting portion 13 and the edge welding strip 3, and thus improving the output power and working stability of the photovoltaic module.

[0109] For example, 1.3 < H1 / H2 ≤ 1.7, and H1 / H2 can be equal to 1.31, 1.33, 1.35, 1.37, 1.39, 1.4, 1.41, 1.43, 1.45, 1.47, 1.49, 1.5, 1.51, 1.53, 1.55, 1.57, 1.59, 1.6, 1.61, 1.63, 1.65, 1.67, 1.69, 1.7, etc.

[0110] For example, 1.7≤H1 / H2≤10.7, where H1 / H2 can be equal to 1.7, 1.71, 1.75, 2, 2.5, 2.7, 3, 3.5, 3.7, 4, 4.5, 4.7, 5, 5.5, 5.7, 6, 6.5, 6.7, 7, 7.5, 7.7, 8, 8.5, 8.7, 9, 9.5, 9.7, 10, 10.5, 10.7, etc.

[0111] For example, 10.7≤H1 / H2≤16.7, where H1 / H2 can be equal to 10.7, 10.71, 10.75, 11, 11.3, 11.5, 11.7, 11.9, 12, 12.1, 12.3, 12.5, 12.7, 12.9, 13, 13.1, 13.3, 13.5, 13.7, 13.9, 14, 14.1, 14.3, 14.5, 14.7, 14.9, 15, 15.1, 15.3, 15.5, 15.7, 15.9, 16, 16.1, 16.3, 16.5, 16.6, 16.69, etc.

[0112] For example, 1.3 < H1 / H2 < 16.7, and H1 / H2 can be equal to 1.31, 1.5, 1.7, 2, 2.7, 3, 3.7, 4, 4.7, 5, 5.7, 6, 6.7, 7, 7.7, 8, 8.7, 9, 9.7, 10, 10.7, 11, 11.7, 12, 12.7, 13, 13.7, 14, 14.7, 15, 15.7, 16, 16.6, etc.

[0113] For example, 16.7≤H1 / H2≤20, where H1 / H2 can be equal to 16.7, 16.8, 16.9, 17, 17.2, 17.4, 17.6, 17.8, 18, 18.2, 18.4, 18.6, 18.8, 19, 19.2, 19.4, 19.6, 19.8, 20, etc.

[0114] For example, 20≤H1 / H2≤55, and H1 / H2 can be equal to 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, etc.

[0115] For example, 55≤H1 / H2≤75, where H1 / H2 can be equal to 55, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 75, etc.

[0116] The width H1 of the second busbar 12 satisfies: 4mm≤H1≤15mm. For example, H1 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, etc.

[0117] For example, 4mm≤H1≤7mm, where H1 can be 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, etc.

[0118] For example, 7mm≤H1≤10mm, where H1 can be 7mm, 7.2mm, 7.4mm, 7.6mm, 7.8mm, 8mm, 8.2mm, 8.4mm, 8.6mm, 8.8mm, 9mm, 9.2mm, 9.4mm, 9.6mm, 9.8mm, 10mm, etc.

[0119] For example, 4mm≤H1≤10mm, where H1 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0120] For example, 10mm≤H1≤15mm, where H1 can be 10mm, 10.2mm, 10.4mm, 10.6mm, 10.8mm, 11mm, 11.2mm, 11.4mm, 11.6mm, 11.8mm, 12mm, 12.2mm, 12.4mm, 12.6mm, 12.8mm, 13mm, 13.2mm, 13.4mm, 13.6mm, 13.8mm, 14mm, 14.2mm, 14.4mm, 14.6mm, 14.8mm, 15mm, etc.

[0121] The width H2 of the connecting part 13 satisfies: 0.2mm≤H2≤3mm. For example, H2 can be 0.2mm, 0.4mm, 0.6mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0122] For example, 0.2mm≤H2≤0.6mm, where H2 can be 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, etc.

[0123] For example, 0.6mm≤H2≤1mm, where H2 can be 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0124] For example, 1mm≤H2≤3mm, where H2 can be 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, etc.

[0125] In the first direction X, the distance between the connecting portion 13 and the edge of the battery cell 301 is greater than 0, and the distance between the connecting portion 13 and the edge of the battery cell 301 is less than or equal to 1.5 mm. For example, in the first direction X, the distance between the connecting portion 13 and the edge of the battery cell 301 can be 0.01 mm, 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, etc.

[0126] In this embodiment, if the distance between the connecting part 13 and the edge of the battery cell 301 is large, the area of ​​the blank area of ​​the photovoltaic module will be large, which will affect the output power of the photovoltaic module.

[0127] Therefore, the distance between the connecting part 13 and the edge of the solar cell 301 is greater than 0, and the distance between the connecting part 13 and the edge of the solar cell 301 is less than or equal to 1.5mm. This reduces the risk of the solar cell 301 being short-circuited by the connecting part 13 due to contact between the connecting part 13 and the solar cell 301, and also reduces the area ratio of the blank area on the photovoltaic module, thereby improving the output power of the photovoltaic module.

[0128] For example, the distance between the connecting portion 13 and the edge of the battery cell 301 is greater than 0, and the distance between the connecting portion 13 and the edge of the battery cell 301 is less than or equal to 0.4 mm. In the first direction X, the distance between the connecting portion 13 and the edge of the battery cell 301 can be 0.01 mm, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, 0.1 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm, 2 mm, 2.1 mm, 2.3 mm, 2.5 mm, 2.7 mm, 2.9 mm, 3 mm, 3.1 mm, 3.3 mm, 3.5 mm, 3.7 mm, 3.9 mm, 4 mm, etc.

[0129] For example, the distance between the connecting portion 13 and the edge of the battery cell 301 is between 0.4 mm and 1.5 mm. In the first direction X, the distance between the connecting portion 13 and the edge of the battery cell 301 can be 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, etc.

[0130] In the second direction Y, the length of the connecting part 13 can be equal to the length of the second busbar 12, that is, the end of the connecting part 13 is aligned with the end of the second busbar 12.

[0131] or, Figure 9 This is a top view of the connection structure between the second busbar 12 and the connecting part 13 in the third direction Z. Figure 9 As shown, the length of the connecting portion 13 is less than the length of the second busbar 12, reducing the risk of the connecting portion 13 protruding from the second busbar 12 in the second direction Y. At this time, a gap needs to be left between the end of the connecting portion 13 and the end of the second busbar 12 in the second direction Y, and the size of the gap in the second direction Y is H3.

[0132] When the second busbar 12 is bent out along the third direction Z and welded to the junction box, 20mm≤H3≤50mm. For example, H3 can be 20mm, 30mm, 40mm, 50mm, etc.

[0133] In this embodiment, if H3 is small, the bending dimension of the reserved second busbar 12 is small, increasing the difficulty of connecting the second busbar 12 to the junction box. If H3 is large, the material cost of the second busbar 12 is high. Therefore, 20mm≤H3≤50mm can reduce the difficulty of connecting the second busbar 12 to the junction box and also reduce the material cost of the second busbar 12.

[0134] For example, 20mm≤H3≤35mm, where H3 can be 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, etc.

[0135] For example, 35mm≤H3≤50mm, where H3 can be 35mm, 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, 50mm, etc.

[0136] When the second busbar 12 does not need to be welded to the junction box, 0mm≤H3≤5mm. For example, H3 can be 0mm, 1mm, 2mm, 3mm, 4mm, 5mm, etc.

[0137] In this embodiment, if H3 is large, the material cost of the second busbar 12 will be high. Therefore, 0mm≤H3≤5mm can reduce the material cost of the second busbar 12.

[0138] For example, 0mm≤H3≤2.5mm, where H3 can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, etc.

[0139] For example, 2.5mm≤H3≤5mm, where H3 can be 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, etc.

[0140] Figure 10 This is a top view of the connection structure between the connecting part 13 and the edge weld strip 3 from a third-degree angle. Figure 10 As shown, the edge solder strip 3 includes a first body 31 and a second body 32 arranged along the first direction X, the first body 31 and... Figure 7 The solar cells 301 are electrically connected, and the second body 32 is electrically connected to the connecting part 13. In the second direction Y, the width of the second body 32 is greater than the width of the first body 31, resulting in a larger contact area between the second body 32 and the connecting part 13. This improves the connection stability between the second body 32 and the connecting part 13, thereby enhancing the working stability of the photovoltaic module. It also reduces the contact resistance between the second body 32 and the connecting part 13, thus increasing the output power of the photovoltaic module.

[0141] On the third direction Z, the thickness of the first body 31 and the second body 32 can be the same or different.

[0142] Figure 11 This is a schematic diagram of a local structure of the edge solder strip. (For example...) Figure 11 As shown, in the third direction Z, the thickness of the second body 32 is less than the thickness of the first body 31. During the processing, the end of the edge welding strip 3 can be flattened to form the second body 32, thereby simplifying the processing of the edge welding strip 3, reducing the processing cost of the edge welding strip 3, and helping to shorten the processing cycle of the edge welding strip 3.

[0143] The thickness of the second body 32 in the third direction Z is 0.1mm to 0.15mm. For example, the thickness of the second body 32 in the third direction Z can be 0.1mm, 0.11mm, 0.13mm, 0.15mm, etc.

[0144] If the thickness of the second body 32 is small, its structural strength will be poor. If the thickness of the second body 32 is large, the contact area between the second body 32 and the connecting part 13 will be small. Therefore, in this embodiment, the thickness of the second body 32 in the third direction Z is 0.1mm to 0.15mm, which can improve the structural strength of the second body 32 and increase the contact area between the second body 32 and the connecting part 13, thereby improving the working stability of the photovoltaic module.

[0145] For example, the thickness of the second body 32 in the third direction Z can be 0.1mm to 0.13mm, and the thickness of the second body 32 can be 0.1mm, 0.105mm, 0.11mm, 0.115mm, 0.12mm, 0.125mm, 0.13mm, etc.

[0146] For example, the thickness of the second body 32 in the third direction Z can be 0.13mm to 0.15mm, and the thickness of the second body 32 can be 0.13mm, 0.135mm, 0.14mm, 0.145mm, 0.15mm, etc.

[0147] Figure 12 This is a cross-sectional view of the connection structure between the second busbar and the battery string in some other embodiments. For example... Figure 12 As shown, the photovoltaic module also includes an insulating strip 5. In the third direction Z, the insulating strip 5 is located between the second busbar 12 and the cell 301. That is, the back surface of the cell 301 and the second busbar 12, and the string bonding strip 302 on the back surface and the second busbar 12 are insulated by the insulating strip 5, which reduces the risk of the cell 301 being short-circuited by the insulating strip 5 due to contact between the second busbar 12 and the cell 301, thereby improving the working stability of the cell 301 and the photovoltaic module.

[0148] like Figure 12 As shown, in the first direction X, the insulating strip 5 extends toward the outside of the cell 301 in the direction toward the connecting part 13. That is, the insulating strip 5 protrudes from the edge of the cell 301 in the first direction X, which further reduces the risk of short circuit of the cell 301 caused by the second busbar 12 contacting the cell 301, and further improves the working stability of the cell 301 and the photovoltaic module.

[0149] like Figure 12 As shown, in the first direction X, the insulating strip 5 contacts the connecting part 13, thereby improving the insulation effect of the insulating strip 5.

[0150] Alternatively, in the first direction X, a gap is left between the insulating strip 5 and the connecting part 13 to reduce the risk of installation difficulties caused by interference between the connecting part 13 and the insulating strip 5, thereby reducing the difficulty of installation.

[0151] Figure 13 This is a cross-sectional view of the insulating strip. (For example...) Figure 13 As shown, the insulating strip 5 includes at least a first layer 51, a second layer 52 and a third layer 53. In the third direction Z, the second layer 52 is located between the first layer 51 and the third layer 53.

[0152] For example, the first layer 51 can be EVA, or it can be an EVA-POE-EVA three-layer co-extruded structure, or it can be PO (Polyolefin).

[0153] For example, the material of the second layer 52 is PET.

[0154] For example, the third layer 53 can be EVA, PO (Polyolefin), or an EVA-POE-EVA three-layer co-extrusion structure.

[0155] In the second direction Y, there is one insulating strip 5. Figure 14 This is a bottom view of the connection structure between the insulating strip and the edge region of the battery cell in some embodiments. The bottom view refers to the diagram obtained by looking at the battery cell from the backside of the cell. For example... Figure 14 As shown, in the edge region, all the battery cells 301 arranged along the second direction Y are connected to the same insulating strip 5.

[0156] In the second direction Y, there are multiple insulating strips 5. Figure 15 This is a bottom view of the connection structure between the insulating strip and the battery cell in the edge region in some other embodiments, such as... Figure 15 As shown, in the second direction Y, there are multiple insulating strips 5, and each insulating strip 5 corresponds to a battery string, that is, each insulating strip 5 corresponds to a battery cell 301 in the edge region.

[0157] In the second direction Y, there are multiple insulating strips 5. Figure 16 This is a bottom view of the connection structure between the insulating strip and the battery cell in the edge region in some other embodiments, such as... Figure 16 As shown, in the second direction Y, there are multiple insulating strips 5, and one insulating strip 5 is connected to at least two battery string groups. That is, in the edge area, at least two battery cells 301 arranged along the second direction Y are connected to the same insulating strip 5.

[0158] The thickness of the insulating strip 5 in the third direction Z is 0.1mm to 0.8mm. For example, the thickness of the insulating strip 5 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, etc.

[0159] For example, the thickness of the insulating strip 5 in the third direction Z is 0.1mm to 0.5mm, and the thickness of the insulating strip 5 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc.

[0160] For example, the thickness of the insulating strip 5 in the third direction Z is 0.5mm to 0.8mm, and the thickness of the insulating strip 5 can be 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, etc.

[0161] In the first direction X, the width of the insulating strip 5 is 6mm to 30mm. For example, the width of the insulating strip 5 can be 6mm, 10mm, 15mm, 20mm, 25mm, 30mm, etc.

[0162] For example, the width of the insulating strip 5 is 6mm to 10mm, and the width of the insulating strip 5 can be 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, etc.

[0163] For example, the width of the insulating strip 5 is 10mm~20mm, and the width of the insulating strip 5 can be 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc.

[0164] For example, the width of the insulating strip 5 is 20mm~30mm, and the width of the insulating strip 5 can be 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, etc.

[0165] Based on the above structure, the edge solder strip 3 is located on the light-facing side of the solar cell 301, or the edge solder strip 3 is located on the back-light-facing side of the solar cell 301.

[0166] Figure 17 This is a cross-sectional view of the connection structure between the second busbar and the battery string in one embodiment. Figure 17As shown, when the second busbar 12 is located on the back surface of the battery cell 301 and the edge solder strip 3 is located on the light-facing surface of the battery cell 301, in the third direction Z, the distance between the light-facing surface of the first body 31 and the back surface of the battery cell 301 is L1, the distance between the light-facing surface of the second busbar 12 and the back surface of the battery cell 301 is L2, and the thickness of the connecting part 13 is L3, where L2≤L3<L1, or L2<L3≤L1, so that the connecting part 13 can be connected to the edge solder strip 3 on the light-facing surface. At the same time, it reduces the risk of the connecting part 13 being too high and lifting the edge solder strip 3 to form a local protrusion, thereby reducing the risk of damage to the laminate at the local protrusion during the lamination process.

[0167] Figure 18 This is a cross-sectional view of the connection structure between the second busbar and the battery string in another embodiment. (See diagram below.) Figure 18 As shown, when the second busbar 12 is located on the back surface of the battery cell 301 and the edge solder strip 3 is located on the back surface of the battery cell 301, in the third direction Z, the distance between the light-facing surface of the first body 31 and the light-facing surface of the second busbar 12 is L4, the distance between the back surface of the first body 31 and the light-facing surface of the second busbar 12 is L5, and the thickness of the connecting part 13 is L6, where L5≤L6<L4, or L5<L6≤L4, so that the connecting part 13 can be connected to the edge solder strip 3 on the back surface. At the same time, it reduces the risk of the connecting part 13 being too high and lifting the edge solder strip 3 to form a local protrusion, thereby reducing the risk of damage to the laminate at the local protrusion during the lamination process.

[0168] On the third-party Z-direction, the thickness of the second busbar 12 is 0.05mm~0.4mm. For example, the thickness of the second busbar 12 can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, etc.

[0169] For example, the thickness of the second busbar 12 is 0.05mm to 0.1mm, and the thickness of the second busbar 12 can be 0.05mm, 0.055mm, 0.06mm, 0.065mm, 0.07mm, 0.075mm, 0.08mm, 0.085mm, 0.09mm, 0.095mm, 0.1mm, etc.

[0170] For example, the thickness of the second busbar 12 is 0.1mm~0.2mm, and the thickness of the second busbar 12 can be 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.2mm, etc.

[0171] For example, the thickness of the second busbar 12 is 0.2mm~0.4mm, and the thickness of the second busbar 12 can be 0.2mm, 0.22mm, 0.24mm, 0.26mm, 0.28mm, 0.3mm, 0.32mm, 0.34mm, 0.36mm, 0.38mm, 0.4mm, etc.

[0172] On the third-party Z-direction, the thickness of the connecting part 13 is 0.2mm to 0.6mm. For example, the thickness of the connecting part 13 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc.

[0173] For example, the thickness of the connecting part 13 is 0.2mm to 0.4mm, and the thickness of the connecting part 13 can be 0.2mm, 0.22mm, 0.24mm, 0.26mm, 0.28mm, 0.3mm, 0.32mm, 0.34mm, 0.36mm, 0.38mm, 0.4mm, etc.

[0174] For example, the thickness of the connecting part 13 is 0.4mm to 0.6mm, and the thickness of the connecting part 13 can be 0.4mm, 0.42mm, 0.44mm, 0.46mm, 0.48mm, 0.5mm, 0.52mm, 0.54mm, 0.56mm, 0.58mm, 0.6mm, etc.

[0175] Based on the aforementioned edge region structure, a second aspect of this application provides a method for manufacturing a photovoltaic module. Figure 19 This is a flowchart of a method for manufacturing photovoltaic modules in some embodiments. For example... Figure 19 As shown, the manufacturing method of photovoltaic modules includes: A1: Preparation of battery string assembly 305.

[0176] A2: Arrange multiple battery string groups 305 along the second direction Y.

[0177] A3: In the first direction X, the connecting part 13 is placed on one or both sides of the battery string 305, the connecting part 13 extends along the second direction Y, and in the third direction Z, the connecting part 13 is located on the back surface of the battery string 305.

[0178] A4: Weld the connecting part 13 to the welding strip 302 on the battery string 305 and fix it in place.

[0179] A5: An encapsulation layer 20 and a cover plate 10 are laid on the light-facing and back-facing surfaces of the battery string 305, and then laminated to form a laminate.

[0180] A6: Install a frame at the edge of the laminate to form a photovoltaic module.

[0181] Before or after step A3, the method for manufacturing photovoltaic modules further includes: A7: Weld the connecting part 13 to the second busbar 12.

[0182] In this embodiment, the second busbar 12 is located on the back surface of the solar cell 301, so that a part of the structure of the second busbar 12 is blocked by the solar cell 301. Without adjusting the size of the solar cell 301 and the second busbar 12 in the first direction X, the total size of the second busbar 12 and the solar cell string 303 in the first direction X can be reduced, thereby reducing the arrangement space of the second busbar 12 and the solar cell string 303, so as to arrange more solar cells 301 in a limited space, thereby increasing the screen ratio of the photovoltaic module and improving the output power of the photovoltaic module.

[0183] Figure 19 The example shows that step A7 is after step A4 and before step A5.

[0184] Figure 20 The flowcharts are shown in some other embodiments of the method for manufacturing photovoltaic modules. Figure 20 The example shows step A7 before step A3.

[0185] Figure 21 The flowcharts for some steps of the manufacturing method of photovoltaic modules in some embodiments are shown below. Figure 21 As shown, prior to step A1, the photovoltaic module manufacturing method further includes: A01: The end of the edge welding strip 3 is flattened to form the second body 32.

[0186] Based on step A01, step A4 includes: A41: Weld the connecting part 13 to the second body 32 to fix it.

[0187] In this embodiment, the end of the edge welding strip 3 is flattened to form the second body 32, so that the second body 32 and the connecting part 13 have a larger contact area, thereby improving the connection stability between the second body 32 and the connecting part 13, and thus improving the working stability of the photovoltaic module.

[0188] Figure 22 This is a schematic diagram of the battery string assembly in some embodiments. For example... Figure 22 As shown, the welding strip 302 at one end of the battery string 303 extends to the outside of the battery cell 301, and the welding strips 302 of adjacent battery strings 303 can be directly welded and fixed.

[0189] based on Figure 22 The structure shown, Figure 23 The flowchart for step A1 in some embodiments is as follows: Figure 23As shown, step A1 includes: A11: Arrange multiple battery cells 301 along the first direction X.

[0190] A12: Place the stringing tape 302 on the battery cell 301 and weld it to form a battery string 303.

[0191] A13: Arrange at least two battery strings 303 along the first direction X.

[0192] A14: Weld the wire bonding strips 302 of adjacent battery strings 303 to form a battery string group 305.

[0193] In the third direction Z, the projections of the string welding strips 302 of adjacent battery strings 303 may or may not have overlapping portions.

[0194] Figure 24 This is a schematic diagram of the battery string assembly in some embodiments, such as... Figure 3 As shown, the string bonding strip 302 includes a first bonding strip 3021 and a second bonding strip 3022. Within a battery string 303, the first bonding strip 3021 is used to connect adjacent battery cells 301, and the second bonding strip 3022 is used to connect adjacent battery strings 303.

[0195] based on Figure 24 The structure shown, Figure 25 Here is a flowchart of step A1 in some other embodiments, such as Figure 25 As shown, step A1 includes: A15: Arrange multiple battery cells 301 along the first direction X.

[0196] A16: Place the first welding strip 3021 on the battery cell 301 and weld it to form a battery string 303.

[0197] A17: Arrange at least two battery strings 303 along the first direction X.

[0198] A18: In the first direction X, the two ends of the second welding strip 3022 are placed on the adjacent battery string 303 and welded to form a battery string group 305.

[0199] When the backlight surface of the battery cell 301 is provided with an insulating strip 5, the insulating strip 5 can be fixed to the battery string 303 first, and then the battery string 303 can be welded into the battery string assembly 305. Alternatively, the battery string 303 can be welded into the battery string assembly 305 first, and then the insulating strip 5 can be fixed to the battery string assembly 305.

[0200] by Figure 25 Taking the process shown as an example, Figure 26 This is a flowchart illustrating the connection between the insulating strip and the battery string in some embodiments. For example... Figure 26As shown, after step A16 and before step A17, the method for manufacturing a photovoltaic module further includes: A02: Place the insulating strip 5 on the battery string 303. In the third direction Z, the insulating strip 5 is located on the back side of the battery cell 301.

[0201] A03: The insulating strip 5 is fixed to the battery string 303 by hot stamping process.

[0202] by Figure 25 Taking the process shown as an example, Figure 27 This is a flowchart illustrating the connection between the insulating strip and the battery string in some other embodiments. For example... Figure 27 As shown, after step A1 and before step A4, the method for manufacturing photovoltaic modules further includes: A04: Place the insulating strip 5 on the battery string 305. In the third direction Z, the insulating strip 5 is located on the back side of the battery cell 301. A05: The insulating strip 5 is fixed to the battery string 305 by hot stamping process.

[0203] In addition, the insulating strip 5 can be connected and fixed to the second busbar 12 first, and then the insulating strip 5 can be fixed to the battery string by hot stamping process. The fixed order of the insulating strip 5 is not particularly limited in this embodiment.

[0204] In steps A03 and A05 above, the specific steps of the hot stamping process can be as follows: Hot air is used to press the insulating strip 5 so that it is fixed to the battery cell 301.

[0205] Alternatively, the specific steps of the hot stamping process can be as follows: Infrared lamps are used to irradiate the insulating strip 5, which fixes the insulating strip 5 onto the battery cell 301.

[0206] The embodiments of this application do not impose special limitations on the specific steps of the hot stamping process.

[0207] In summary, in the photovoltaic module manufacturing method provided in this application embodiment, the connecting part 13 can be fixed to the battery string group 305 first, and then the second busbar 12 can be connected and fixed to the connecting part 13. Alternatively, the connecting part 13 and the second busbar 12 can be connected and fixed as a whole first, and then this whole can be fixed to the battery string group 305.

[0208] The insulating strip 5 can be fixed to the battery string 303 first, and then the battery string 303 can be connected to form the battery string group 305. Alternatively, the battery string 303 can be connected to form the battery string group 305 first, and then the insulating strip 5 can be fixed to the battery string group 305.

[0209] It should be noted that if the battery string 303 is first connected to form the battery string group 305, and then the connecting part 13, the second bus bar 12 and the insulating bar 5 are fixed to the battery string group 305, then there are the following two steps: The first method involves fixing the insulating strip 5 to the battery string 305, and then fixing the connecting part 13 and the second busbar 12 to the battery string.

[0210] The second method involves first connecting the connecting part 13, the second busbar 12, and the insulating strip 5 into a whole, and then attaching this whole battery string 305.

[0211] The connection structure of the edge region will be discussed in detail next.

[0212] like Figure 3 and Figure 5 As shown, in the first direction X, the busbar 304 includes an interconnecting strip 2 located between adjacent battery strings 303, and the stringing strip 302 includes an electrical connector 4. The two ends of the electrical connector 4 are electrically connected to the battery cells 301 on the adjacent battery strings 303, so that the adjacent battery strings 303 are connected in series or in parallel to form a battery string group 305. Multiple battery string groups 305 are arranged along the second direction Y. In the second direction Y, at least two battery string groups 305 are electrically connected to the same interconnecting strip 2, so that the adjacent battery string groups 305 are connected in series or in parallel.

[0213] Figure 28 This is a cross-sectional view of the connection structure between the interconnecting strips and the battery string in related technologies. (Example) Figure 28 As shown, the interconnecting strip 2 in the related technology is referred to as the first interconnecting strip 21. The first interconnecting strip 21 and the adjacent battery cell 301 have a large second gap 211 in the first direction X. In the first direction X, the size of the second gap 211 needs to be larger than the size of the first interconnecting strip 21, so that the projection of the first interconnecting strip 21 is completely located within the second gap 211.

[0214] The aforementioned second gap 211 results in a larger arrangement space for the first interconnecting strip 21 and the battery string 303. In order to meet the arrangement space of the first interconnecting strip 21 within the limited space, the number of battery strings 303 needs to be sacrificed, which affects the output power of the photovoltaic module.

[0215] Therefore, in order to reduce the arrangement space of interconnecting strip 2 and battery string 303, Figure 29 Cross-sectional views of the interconnection structure between the interconnecting strip and the battery string provided in embodiments of this application in some embodiments. For example... Figure 29As shown, the interconnecting strip 2 in this embodiment is referred to as the second interconnecting strip 22. The busbar 304 also includes an interconnecting part 23. In the third direction Z, the interconnecting part 23 is located on the side of the second interconnecting strip 22 facing the battery cell 301. In the first direction X, at least a portion of the structure of the interconnecting part 23 is located between two adjacent battery strings 303. The second interconnecting strip 22 and the electrical connector 4 are electrically connected through the interconnecting part 23, so that adjacent battery strings 303 in the first direction X are electrically connected through the second interconnecting strip 22, and adjacent battery string groups 305 in the second direction Y are electrically connected through the second interconnecting strip 22.

[0216] The second interconnecting strip 22 is located on the back surface of the battery string 305, that is, on the third direction Z. A part of the structure of the second interconnecting strip 22 is located on the back surface of the battery cell 301, so that the projection of the second interconnecting strip 22 on the third direction Z overlaps with the projection of the battery cell 301 on the third direction Z.

[0217] In this embodiment, the second interconnecting strip 22 is located on the back surface of the solar cell 301, so that a part of the structure of the second interconnecting strip 22 is blocked by the solar cell 301. Without adjusting the size of the solar cell 301 and the second interconnecting strip 22 in the first direction X, the total size of the second interconnecting strip 22 and the solar cell string 303 in the first direction X can be reduced, thereby reducing the arrangement space of the second interconnecting strip 22 and the solar cell string 303, so as to arrange more solar cells 301 in a limited space, thereby increasing the screen ratio of the photovoltaic module and improving the output power of the photovoltaic module.

[0218] based on Figure 28 According to the related technology shown, if the first interconnecting strip 21 is to be placed on the backlight surface of the battery cell 301, the first interconnecting strip 21 needs to be folded. The structure after folding is as follows: Figure 30 As shown, at this time, a portion of the electrical connector 4 is folded onto the back surface of the battery cell 301 along with the first interconnect strip 21. At the first interconnect strip 21, the total thickness of the battery layer 30 is the thickness of the electrical connector 4 on the light-facing side, the thickness of the battery cell 301, the thickness of the first interconnect strip 21, and the thickness of the two layers of electrical connector 4 on the back surface. This results in a localized increase in the thickness of the battery layer 30, which increases the risk of microcracks during subsequent lamination. Simultaneously, the folding of the electrical connector 4 can lead to breakage and damage, and also increases the risk of solder joint cracking.

[0219] Therefore, as Figure 29As shown, in this embodiment, the second interconnect strip 22 and the electrical connector 4 are electrically connected by an interconnect portion 23 extending along the third direction Z, which reduces the risk of the electrical connector 4 being bent and broken, or the solder joints cracking. It also reduces the risk of hidden cracks appearing in the lamination process due to the local increase in the thickness of the battery layer 30, thereby improving the processing yield and working stability of the photovoltaic module.

[0220] like Figure 7 As shown, in the first direction X, the distance of the edge solder strip 3 beyond the edge of the battery cell 301 is H0, 1mm≤H0≤5mm. For example, the distance of the edge solder strip 3 beyond the edge of the battery cell 301 is 1mm, 1.5mm, 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, etc.

[0221] If the edge solder strip 3 extends a large distance beyond the edge of the cell 301, the size of the cell layer in the first direction X will be large, but the actual area of ​​the cell 301 will be small, affecting the output power of the photovoltaic module.

[0222] If the distance between the edge welding strip 3 and the edge of the battery cell 301 is small, the connection between the edge welding strip 3 and the connecting part 13 will be more difficult, and there is a risk that the connection size between the edge welding strip 3 and the connecting part 13 will be small and the connection stability will be poor.

[0223] Therefore, 1mm≤H0≤5mm can increase the proportion of the area of ​​the cell 301 in the total area of ​​the cell layer, and can also improve the connection stability between the edge solder strip 3 and the connection part 13, thereby improving the output power of the photovoltaic module.

[0224] For example, 1mm≤H0≤2.5mm, the distance of the edge welding strip 3 extending beyond the edge of the battery cell 301 is 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, etc.

[0225] For example, 2.5mm≤H0≤5mm, the distance of the edge welding strip 3 extending beyond the edge of the battery cell 301 is 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, etc.

[0226] The second interconnecting strip 22 and the interconnecting part 23 can be integrally formed to simplify the connection and shorten the connection cycle.

[0227] Alternatively, the second interconnecting strip 22 and the interconnecting part 23 can be separate structures, and the second interconnecting strip 22 and the interconnecting part 23 can be fixedly connected by welding or hot pressing to reduce the processing difficulty of the second interconnecting strip 22 and the interconnecting part 23 and shorten the processing cycle. In this case, the interconnecting part 23 can be a welding strip, and the cross-sectional shape of the interconnecting part 23 can be circular or rectangular, that is, the interconnecting part 23 can be a round welding strip or a flat welding strip.

[0228] The interconnecting part 23 and the electrical connector 4 are fixedly connected by welding or hot pressing to reduce the processing difficulty of the interconnecting part 23 and the electrical connector 4 and shorten the processing cycle.

[0229] like Figure 29 As shown, the battery string group 305 includes at least a first battery string 3031 and a second battery string 3032 arranged along the first direction X. The first battery string 3031 includes a first end battery piece 3011, and the second battery string 3032 includes a second end battery piece 3012. In the first direction X, the first end battery piece 3011 and the second end battery piece 3012 are adjacent to each other.

[0230] On the third-party direction Z, the projection of the second interconnecting strip 22 overlaps with the projection of the first end battery cell 3011, and / or, the projection of the second interconnecting strip 22 overlaps with the projection of the second end battery cell 3012.

[0231] For example, on the third-party direction Z, the projection of the second interconnecting strip 22 overlaps with the projection of the first end battery cell 3011, while the projection of the second interconnecting strip 22 does not overlap with the projection of the second end battery cell 3012.

[0232] For example, on the third-party direction Z, the projection of the second interconnecting strip 22 and the projection of the first end battery cell 3011 do not overlap, while the projection of the second interconnecting strip 22 and the projection of the second end battery cell 3012 do overlap.

[0233] For example, on the third-party direction Z, the projection of the second interconnecting strip 22 overlaps with the projection of the first end battery cell 3011, and the projection of the second interconnecting strip 22 overlaps with the projection of the second end battery cell 3012.

[0234] In this embodiment, the projections of the second interconnecting strip 22 and the first end cell 3011 overlap, and the projections of the second interconnecting strip 22 and the second end cell 3012 also overlap. This can further reduce the distance between adjacent cell strings 303 in the first direction X, thereby further increasing the number of cells 301 that can be installed, so as to improve the output power of the photovoltaic module.

[0235] like Figure 29 As shown, in the third direction Z, the geometric center of the second interconnecting strip 22 is located within the projection area of ​​the interconnecting part 23, that is, the interconnecting part 23 is located at the center of the second interconnecting strip 22, so that the distance between the interconnecting part 23 and the battery cells 301 on both sides is equal or close, so as to improve the uniformity of the battery string 303 in the first direction X.

[0236] like Figure 29 As shown, in the first direction X, there is a gap between the interconnect 23 and the battery cell 301, thereby reducing the risk of short circuit of the battery cell 301 caused by direct contact between the interconnect 23 and the battery cell 301.

[0237] like Figure 29 As shown, in the first direction X, the width of the second interconnecting strip 22 is H4, and the width of the interconnecting part 23 is H5, where 1.3 < H4 / H5 ≤ 75. For example, H4 / H5 can be equal to 1.31, 1.5, 1.7, 2, 2.7, 3, 3.7, 4, 4.7, 5, 5.7, 6, 6.7, 7, 7.7, 8, 8.7, 9, 9.7, 10, 10.7, 11, 11.7, 12, 12.7, 13, 13.7, 14, 14.7, 15, 15.7, 16, 16.6, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, etc.

[0238] If the value of H4 / H5 is small, the width difference between the second interconnect strip 22 and the interconnect part 23 is small, and the risk of short circuit of the battery cell 301 due to contact between the interconnect part 23 and the battery cell 301 is high.

[0239] If the ratio of H4 / H5 is large, the width of the second interconnecting strip 22 will be large, resulting in a higher material cost for the second interconnecting strip 22. Alternatively, if the width of the interconnecting part 23 is small, the current transmission capability of the interconnecting part 23 will be poor, which will also result in a poor connection stability between the interconnecting part 23 and the electrical connector 4.

[0240] Therefore, in this embodiment, 1.3 < H4 / H5 ≤ 75 can increase the width difference between the second interconnect strip 22 and the interconnect portion 23, thereby reducing the risk of short circuit in the battery cell 301 caused by contact between the interconnect portion 23 and the battery cell 301. At the same time, it can also reduce the width of the second interconnect strip 22, reduce the material cost of the second interconnect strip 22, and increase the width of the interconnect portion 23, thereby improving the current transmission capability of the interconnect portion 23 and the connection stability between the interconnect portion 23 and the electrical connector 4, and thus improving the output power and operating stability of the photovoltaic module.

[0241] For example, 1.3 < H4 / H5 ≤ 1.7, and H4 / H5 can be equal to 1.31, 1.33, 1.35, 1.37, 1.39, 1.4, 1.41, 1.43, 1.45, 1.47, 1.49, 1.5, 1.51, 1.53, 1.55, 1.57, 1.59, 1.6, 1.61, 1.63, 1.65, 1.67, 1.69, 1.7, etc.

[0242] For example, 1.7≤H4 / H5≤10.7, where H4 / H5 can be equal to 1.7, 1.71, 1.75, 2, 2.5, 2.7, 3, 3.5, 3.7, 4, 4.5, 4.7, 5, 5.5, 5.7, 6, 6.5, 6.7, 7, 7.5, 7.7, 8, 8.5, 8.7, 9, 9.5, 9.7, 10, 10.5, 10.7, etc.

[0243] For example, 10.7≤H4 / H5≤16.7, where H4 / H5 can be equal to 10.7, 10.71, 10.75, 11, 11.3, 11.5, 11.7, 11.9, 12, 12.1, 12.3, 12.5, 12.7, 12.9, 13, 13.1, 13.3, 13.5, 13.7, 13.9, 14, 14.1, 14.3, 14.5, 14.7, 14.9, 15, 15.1, 15.3, 15.5, 15.7, 15.9, 16, 16.1, 16.3, 16.5, 16.6, 16.69, etc.

[0244] For example, 1.3 < H1 / H2 < 16.7, and H1 / H2 can be equal to 1.31, 1.5, 1.7, 2, 2.7, 3, 3.7, 4, 4.7, 5, 5.7, 6, 6.7, 7, 7.7, 8, 8.7, 9, 9.7, 10, 10.7, 11, 11.7, 12, 12.7, 13, 13.7, 14, 14.7, 15, 15.7, 16, 16.6, etc.

[0245] For example, 16.7≤H1 / H2≤20, where H1 / H2 can be equal to 16.7, 16.8, 16.9, 17, 17.2, 17.4, 17.6, 17.8, 18, 18.2, 18.4, 18.6, 18.8, 19, 19.2, 19.4, 19.6, 19.8, 20, etc.

[0246] For example, 20≤H1 / H2≤55, and H1 / H2 can be equal to 20, 22, 24, 26, 28, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, 50, etc.

[0247] For example, 55≤H1 / H2≤75, where H1 / H2 can be equal to 55, 56, 58, 60, 62, 64, 66, 68, 70, 72, 74, 75, etc.

[0248] The width H4 of the second interconnecting strip 22 satisfies: 4mm≤H4≤15mm. For example, H4 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, etc.

[0249] For example, 4mm≤H4≤7mm, where H4 can be 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, etc.

[0250] For example, 7mm≤H4≤10mm, where H4 can be 7mm, 7.2mm, 7.4mm, 7.6mm, 7.8mm, 8mm, 8.2mm, 8.4mm, 8.6mm, 8.8mm, 9mm, 9.2mm, 9.4mm, 9.6mm, 9.8mm, 10mm, etc.

[0251] For example, 4mm≤H4≤10mm, where H4 can be 4mm, 5mm, 6mm, 7mm, 8mm, 9mm, 10mm, etc.

[0252] For example, 10mm≤H4≤15mm, where H4 can be 10mm, 10.2mm, 10.4mm, 10.6mm, 10.8mm, 11mm, 11.2mm, 11.4mm, 11.6mm, 11.8mm, 12mm, 12.2mm, 12.4mm, 12.6mm, 12.8mm, 13mm, 13.2mm, 13.4mm, 13.6mm, 13.8mm, 14mm, 14.2mm, 14.4mm, 14.6mm, 14.8mm, 15mm, etc.

[0253] The width H5 of the interconnecting part 23 satisfies: 0.2mm≤H5≤3mm. For example, H5 can be 0.2mm, 0.4mm, 0.6mm, 1mm, 1.5mm, 2mm, 2.5mm, 3mm, etc.

[0254] For example, 0.2mm≤H5≤0.6mm, where H5 can be 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, 0.55mm, 0.6mm, etc.

[0255] For example, 0.6mm≤H5≤1mm, where H5 can be 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, etc.

[0256] For example, 1mm≤H5≤3mm, where H5 can be 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, etc.

[0257] In the first direction X, the distance between the interconnect portion 23 and the edge of the battery cell 301 is greater than 0, and the distance between the interconnect portion 23 and the edge of the battery cell 301 is less than or equal to 1.5 mm. For example, in the first direction X, the distance between the interconnect portion 23 and the edge of the battery cell 301 can be 0.01 mm, 0.1 mm, 0.2 mm, 0.4 mm, 0.6 mm, 0.8 mm, 1 mm, 1.2 mm, 1.4 mm, 1.5 mm, etc.

[0258] In this embodiment, if the distance between the interconnection part 23 and the edge of the battery cell 301 is large, the area of ​​the blank area of ​​the photovoltaic module will be large, which will affect the output power of the photovoltaic module.

[0259] Therefore, the distance between the interconnection part 23 and the edge of the cell 301 is greater than 0, and the distance between the interconnection part 23 and the edge of the cell 301 is less than or equal to 1.5mm. This reduces the risk of the cell 301 being short-circuited by the interconnection part 23 due to contact between the interconnection part 23 and the cell 301, and also reduces the area ratio of blank areas on the photovoltaic module, thereby improving the output power of the photovoltaic module.

[0260] For example, the distance between the interconnection portion 23 and the edge of the battery cell 301 is greater than 0, and the distance between the interconnection portion 23 and the edge of the battery cell 301 is less than or equal to 0.4 mm. In the first direction X, the distance between the interconnection portion 23 and the edge of the battery cell 301 can be 0.01 mm, 0.02 mm, 0.04 mm, 0.06 mm, 0.08 mm, 0.1 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm, 2 mm, 2.1 mm, 2.3 mm, 2.5 mm, 2.7 mm, 2.9 mm, 3 mm, 3.1 mm, 3.3 mm, 3.5 mm, 3.7 mm, 3.9 mm, 4 mm, etc.

[0261] For example, the distance between the interconnection portion 23 and the edge of the battery cell 301 is between 0.4 mm and 1.5 mm. In the first direction X, the distance between the interconnection portion 23 and the edge of the battery cell 301 can be 0.4 mm, 0.5 mm, 0.6 mm, 0.7 mm, 0.8 mm, 0.9 mm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, etc.

[0262] In the second direction Y, the length of the interconnecting part 23 can be equal to the length of the second interconnecting strip 22, that is, the end of the interconnecting part 23 is aligned with the end of the second interconnecting strip 22.

[0263] or, Figure 31 This is a top view of the connection structure between the second interconnecting strip and the interconnecting part from a third-party perspective. (See attached image.) Figure 31 As shown, the length of the interconnect portion 23 is less than the length of the second interconnect strip 22, reducing the risk of the interconnect portion 23 protruding from the second interconnect strip 22 in the second direction Y. At this time, a gap needs to be left between the end of the interconnect portion 23 and the end of the second interconnect strip 22 in the second direction Y, and the size of the gap in the second direction Y is H6.

[0264] When the second interconnecting strip 22 is bent out along the third direction Z and welded to the junction box, 20mm≤H6≤50mm. For example, H6 can be 20mm, 30mm, 40mm, 50mm, etc.

[0265] In this embodiment, if H6 is small, the bending dimension of the reserved second interconnecting strip 22 is small, increasing the difficulty of connecting the second interconnecting strip 22 to the junction box. If H6 is large, the material cost of the second interconnecting strip 22 is high. Therefore, 20mm≤H6≤50mm can reduce the difficulty of connecting the second interconnecting strip 22 to the junction box and also reduce the material cost of the second interconnecting strip 22.

[0266] For example, 20mm≤H6≤35mm, where H6 can be 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, 31mm, 32mm, 33mm, 34mm, 35mm, etc.

[0267] For example, 35mm≤H6≤50mm, where H6 can be 35mm, 36mm, 37mm, 38mm, 39mm, 40mm, 41mm, 42mm, 43mm, 44mm, 45mm, 46mm, 47mm, 48mm, 49mm, 50mm, etc.

[0268] When the second interconnecting strip 22 does not need to be welded to the junction box, 0mm≤H6≤5mm. For example, H6 can be 0mm, 1mm, 2mm, 3mm, 4mm, 5mm, etc.

[0269] In this embodiment, if H6 is large, the material cost of the second interconnecting strip 22 will be high. Therefore, 0mm≤H6≤5mm can reduce the material cost of the second interconnecting strip 22.

[0270] For example, 0mm≤H6≤2.5mm, where H6 can be 0mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, 0.9mm, 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, etc.

[0271] For example, 2.5mm≤H6≤5mm, where H6 can be 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, 5mm, etc.

[0272] Figure 32 This is a top view of the connection structure between the interconnecting parts and the electrical connectors from a third-party perspective. (Example:) Figure 32 As shown, the electrical connector 4 includes an electrical connector body 41 and an electrical connector portion 42. The electrical connector body 41 includes a first electrical connector body 411 and a second electrical connector body 412. In the first direction X, the electrical connector portion 42 is located between the first electrical connector body 411 and the second electrical connector body 412. The first electrical connector body 411 and the second electrical connector body 412 are electrically connected to adjacent battery strings 303 respectively. The electrical connector portion 42 is electrically connected to the interconnection portion 23.

[0273] In the second direction Y, the width of the electrical connection portion 42 is greater than the width of the first electrical connection body 411, and the width of the electrical connection portion 42 is greater than the width of the second electrical connection body 412. This results in a larger contact area between the electrical connection portion 42 and the interconnection portion 23, thereby improving the connection stability between the electrical connection portion 42 and the interconnection portion 23, which in turn improves the working stability of the photovoltaic module. It can also reduce the contact resistance between the electrical connection portion 42 and the interconnection portion 23, thereby increasing the output power of the photovoltaic module.

[0274] On the third direction Z, the thickness of the electrical connection portion 42 and the first electrical connection body 411 can be the same or different, and the thickness of the electrical connection portion 42 and the second electrical connection body 412 can be the same or different.

[0275] Figure 33 This is a partial structural diagram of an electrical connector. (For example...) Figure 33As shown, in the third direction Z, the thickness of the electrical connection portion 42 is less than the thickness of the first electrical connection body 411, and the thickness of the electrical connection portion 42 is less than the thickness of the second electrical connection body 412. During the processing, the middle part of the electrical connector 4 can be flattened to form the second body 32, thereby simplifying the processing of the edge solder strip 3, reducing the processing cost of the edge solder strip 3, and helping to shorten the processing cycle of the edge solder strip 3.

[0276] The thickness of the electrical connection portion 42 in the third direction Z is 0.1mm to 0.15mm. For example, the thickness of the electrical connection portion 42 in the third direction Z can be 0.1mm, 0.11mm, 0.13mm, 0.15mm, etc.

[0277] If the thickness of the electrical connection portion 42 is small, its structural strength will be poor. If the thickness of the electrical connection portion 42 is large, the contact area between the electrical connection portion 42 and the interconnect portion 23 will be small. Therefore, in this embodiment, the thickness of the electrical connection portion 42 in the third direction Z is 0.1mm to 0.15mm, which can improve the structural strength of the electrical connection portion 42 and increase the contact area between the electrical connection portion 42 and the interconnect portion 23, thereby improving the working stability of the photovoltaic module.

[0278] For example, the thickness of the electrical connection portion 42 in the third direction Z can be 0.1mm to 0.13mm, and the thickness of the electrical connection portion 42 can be 0.1mm, 0.105mm, 0.11mm, 0.115mm, 0.12mm, 0.125mm, 0.13mm, etc.

[0279] For example, the thickness of the electrical connection portion 42 in the third direction Z can be 0.13mm to 0.15mm, and the thickness of the electrical connection portion 42 can be 0.13mm, 0.135mm, 0.14mm, 0.145mm, 0.15mm, etc.

[0280] The first electrical connection body 411, the electrical connection part 42, and the second electrical connection body 412 can be either separate structures or integrally formed structures.

[0281] like Figure 33 As shown, the electrical connection part 42 includes a first connection segment 421 and a second connection segment 422. The first connection segment 421 and the first electrical connection body 411 are integrally formed, and the second connection segment 422 and the second electrical connection body 412 are integrally formed. The first connection segment 421 and the second connection segment 422 are connected and fixed.

[0282] The structure formed by the second connecting segment 422 and the second electrical connecting body 412 is designated as the first electrical connector 43, and the structure formed by the first connecting segment 421 and the second connecting segment 422 is designated as the second electrical connector 44. During the processing, the first electrical connector 43 and the second electrical connector 44 can be processed separately. Then, the first electrical connector 43 is welded to the first end battery cell 3011, and the second electrical connector 44 is welded to the second end battery cell 3012. Then, the first connecting segment 421 and the second connecting segment 422 are connected and fixed, thereby connecting adjacent battery strings 303 into a battery string group 305.

[0283] In this embodiment, the electrical connector 4 used to connect two adjacent battery strings 303 is formed by connecting a first electrical connector 43 and a second electrical connector 44 that are separately arranged, so that the first electrical connector 43 and the second electrical connector 44 can be welded and fixed to the battery cell 301 respectively, thereby simplifying the connection difficulty between the first electrical connector 43 and the second electrical connector 44 and the battery cell 301 and reducing the manufacturing difficulty of the battery string group 305.

[0284] The first connecting segment 421 and the second connecting segment 422 can be directly connected or indirectly connected through the interconnection section 23.

[0285] When the first connecting segment 421 and the second connecting segment 422 are directly connected, the first connecting segment 421 and the second connecting segment 422 are respectively connected and fixed to the interconnection part 23, thereby improving the connection stability between the first electrical connector 43 and the interconnection part 23, and between the second electrical connector 44 and the interconnection part 23.

[0286] When the first connecting segment 421 and the second connecting segment 422 are directly connected, such as Figure 32 As shown, the first connecting segment 421 and the second connecting segment 422 can be arranged opposite to each other and in contact along the first direction X, and the two are connected and fixed at the contact surface.

[0287] When the first connecting segment 421 and the second connecting segment 422 are directly connected Figure 34 This is a top view of the electrical connector in some other embodiments, such as... Figure 34 As shown, the first connecting segment 421 and the second connecting segment 422 can be staggered and contacted along the second direction Y, and the two are connected and fixed at the contact surface.

[0288] When the first connecting segment 421 and the second connecting segment 422 are directly connected Figure 35 This is a partial structural diagram of the electrical connector in some other embodiments, such as... Figure 35 As shown, in the third direction Z, the projections of the first connecting segment 421 and the second connecting segment 422 may overlap, that is, the first connecting segment 421 and the second connecting segment 422 are stacked along the third direction Z, and the two are connected and fixed at the contact surface.

[0289] When the first connecting segment 421 and the second connecting segment 422 are indirectly connected through the interconnection part 23, the first connecting segment 421 and the second connecting segment 422 may be in contact or have a gap. The arrangement of the first connecting segment 421 and the second connecting segment 422 can be referred to Figures 32 to 35 The method shown is not elaborated here.

[0290] Figure 36 This is a cross-sectional view of the connection structure between the second interconnecting bar and the battery string in some other embodiments. For example... Figure 36 As shown, the photovoltaic module also includes an isolator 6. In the third direction Z, the isolator 6 is located between the second interconnect strip 22 and the cell 301. That is, the back surface of the cell 301 is insulated from the second interconnect strip 22, and the string bonding strip 302 on the back surface is insulated from the second interconnect strip 22 through the isolator 6. This reduces the risk of the cell 301 being short-circuited by the second interconnect strip 22 due to contact between the second interconnect strip 22 and the cell 301, thereby improving the working stability of the cell 301 and the photovoltaic module.

[0291] like Figure 36 As shown, in the first direction X, the separator 6 extends toward the outside of the cell 301 in the direction toward the interconnection part 23. That is, the separator 6 protrudes from the edge of the cell 301 in the first direction X, which further reduces the risk of short circuit of the cell 301 caused by the second interconnection strip 22 contacting the cell 301, and further improves the working stability of the cell 301 and the photovoltaic module.

[0292] like Figure 36 As shown, in the first direction X, the insulating member 6 contacts the interconnecting part 23, thereby improving the insulation effect of the insulating member 6.

[0293] Alternatively, in the first direction X, a gap is left between the isolator 6 and the interconnection part 23 to reduce the risk of installation difficulties caused by interference between the isolator 6 and the interconnection part 23, thereby reducing the installation difficulty.

[0294] Figure 37 This is a sectional view of the isolation component. (e.g.) Figure 37 As shown, the isolation member 6 includes at least a first isolation layer 61, a second isolation layer 62 and a third isolation layer 63. In the third direction Z, the second isolation layer 62 is located between the first isolation layer 61 and the third isolation layer 63.

[0295] For example, the first isolation layer 61 can be EVA, or it can be an EVA-POE-EVA three-layer co-extruded structure, or it can be PO (Polyolefin).

[0296] For example, the material of the second isolation layer 62 is PET.

[0297] For example, the third isolation layer 63 can be EVA, PO (Polyolefin), or a three-layer co-extruded structure of EVA-POE-EVA.

[0298] In the second direction Y, the number of isolation element 6 is one. Figure 38 This is a bottom view of the connection structure between the separator and the first end cell in some embodiments. The bottom view refers to the diagram obtained by looking at the cell from the backside of the cell. For example... Figure 38 As shown, in the middle region of the battery string group 305, on a battery string 303 of a battery string group 305, all the battery cells 301 arranged along the second direction Y are connected to the same separator 6, that is, all the first end battery cells 3011 arranged along the second direction Y are connected to the same separator 6, and all the second end battery cells 3012 arranged along the second direction Y are connected to the same separator 6.

[0299] In the second direction Y, there are multiple isolation elements 6. Figure 39 This is a bottom view of the connection structure between the separator and the first end battery cell in some other embodiments, such as... Figure 39 As shown, in the second direction Y, there are multiple isolation members 6, and each isolation member 6 corresponds to a battery string group, that is, each isolation member 6 corresponds to a battery cell 3011 at the first end of the middle region, and each isolation member 6 corresponds to a battery cell 3012 at the second end of the middle region.

[0300] In the second direction Y, there are multiple isolation elements 6. Figure 40 A bottom view of the connection structure between the separator and the first end battery cell in some other embodiments, such as Figure 40 As shown, in the second direction Y, there are multiple separators 6. One separator 6 is connected to at least two battery string groups. That is, in the middle region, at least two first end battery cells 3011 arranged along the second direction Y are connected to the same separator 6, and at least two second end battery cells 3012 arranged along the second direction Y are connected to the same separator 6.

[0301] The thickness of the separator 6 in the third direction Z is 0.1mm to 0.8mm. For example, the thickness of the separator 6 can be 0.1mm, 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, 0.7mm, 0.8mm, etc.

[0302] For example, the thickness of the separator 6 in the third direction Z is 0.1mm to 0.5mm, and the thickness of the separator 6 can be 0.1mm, 0.15mm, 0.2mm, 0.25mm, 0.3mm, 0.35mm, 0.4mm, 0.45mm, 0.5mm, etc.

[0303] For example, the thickness of the spacer 6 in the third direction Z is 0.5mm to 0.8mm, and the thickness of the spacer 6 can be 0.5mm, 0.55mm, 0.6mm, 0.65mm, 0.7mm, 0.75mm, 0.8mm, etc.

[0304] In the first direction X, the width of the spacer 6 is 6mm to 30mm. For example, the width of the spacer 6 can be 6mm, 10mm, 15mm, 20mm, 25mm, 30mm, etc.

[0305] For example, the width of the spacer 6 is 6mm to 10mm, and the width of the spacer 6 can be 6mm, 6.5mm, 7mm, 7.5mm, 8mm, 8.5mm, 9mm, 9.5mm, 10mm, etc.

[0306] For example, the width of the spacer 6 is 10mm to 20mm, and the width of the spacer 6 can be 10mm, 11mm, 12mm, 13mm, 14mm, 15mm, 16mm, 17mm, 18mm, 19mm, 20mm, etc.

[0307] For example, the width of the spacer 6 is 20mm~30mm, and the width of the spacer 6 can be 20mm, 21mm, 22mm, 23mm, 24mm, 25mm, 26mm, 27mm, 28mm, 29mm, 30mm, etc.

[0308] Based on the above structure, the electrical connector 4 is located on the light-facing surface of the battery cell 301, or the electrical connector 4 is located on the back-lighting surface of the battery cell 301.

[0309] Figure 41 This is a cross-sectional view of the middle region of the battery string assembly in one embodiment. Figure 41 As shown, when the second interconnecting strip 22 is located on the backlight surface of the battery cell 301 and the electrical connector 4 is located on the light-facing surface of the battery cell 301, in the third direction Z, the distance between the light-facing surface of the electrical connector body 41 and the backlight surface of the battery cell 301 is W1, the distance between the light-facing surface of the second interconnecting strip 22 and the backlight surface of the battery cell 301 is W2, and the thickness of the interconnecting part 23 is W3, where W2≤W3<W1, or W2<W3≤W1. This allows the interconnecting part 23 to connect with the electrical connector 4 on the light-facing surface. At the same time, it reduces the risk of the interconnecting part 23 being too high and lifting the electrical connector 4, thus reducing the risk of damage to the laminate at the local protrusion during the lamination process.

[0310] Figure 42 This is a cross-sectional view of the middle region of the battery string assembly in another embodiment. (See image.) Figure 42As shown, when the second interconnecting strip 22 is located on the backlight surface of the battery cell 301 and the electrical connector 4 is located on the backlight surface of the battery cell 301, in the third direction Z, the distance between the light-facing surface of the electrical connector body 41 and the light-facing surface of the second interconnecting strip 22 is W4, the distance between the backlight surface of the electrical connector body 41 and the light-facing surface of the second interconnecting strip 22 is W5, and the thickness of the interconnecting part 23 is W6, where W5≤W6<W4, or W5<W6≤W4. This allows the interconnecting part 23 to connect with the electrical connector 4 on the backlight surface. At the same time, it reduces the risk of the interconnecting part 23 being too high and lifting the electrical connector 4, thus reducing the risk of damage to the laminate at the local protrusion during the lamination process.

[0311] On the third-party Z, the thickness of the second interconnecting strip 22 is 0.05mm~0.4mm. For example, the thickness of the second interconnecting strip 22 can be 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.2mm, 0.3mm, 0.4mm, etc.

[0312] For example, the thickness of the second interconnecting strip 22 is 0.05mm~0.1mm, and the thickness of the second interconnecting strip 22 can be 0.05mm, 0.055mm, 0.06mm, 0.065mm, 0.07mm, 0.075mm, 0.08mm, 0.085mm, 0.09mm, 0.095mm, 0.1mm, etc.

[0313] For example, the thickness of the second interconnecting strip 22 is 0.1mm~0.2mm, and the thickness of the second interconnecting strip 22 can be 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm, 0.19mm, 0.2mm, etc.

[0314] For example, the thickness of the second interconnecting strip 22 is 0.2mm to 0.4mm, and the thickness of the second interconnecting strip 22 can be 0.2mm, 0.22mm, 0.24mm, 0.26mm, 0.28mm, 0.3mm, 0.32mm, 0.34mm, 0.36mm, 0.38mm, 0.4mm, etc.

[0315] On the third-party Z, the thickness of the interconnect part 23 is 0.2mm to 0.6mm. For example, the thickness of the interconnect part 23 can be 0.2mm, 0.3mm, 0.4mm, 0.5mm, 0.6mm, etc.

[0316] For example, the thickness of the interconnect part 23 is 0.2mm to 0.4mm, and the thickness of the interconnect part 23 can be 0.2mm, 0.22mm, 0.24mm, 0.26mm, 0.28mm, 0.3mm, 0.32mm, 0.34mm, 0.36mm, 0.38mm, 0.4mm, etc.

[0317] For example, the thickness of the interconnect part 23 is 0.4mm to 0.6mm, and the thickness of the interconnect part 23 can be 0.4mm, 0.42mm, 0.44mm, 0.46mm, 0.48mm, 0.5mm, 0.52mm, 0.54mm, 0.56mm, 0.58mm, 0.6mm, etc.

[0318] Based on the structure of the aforementioned intermediate region, a third aspect of this application provides a method for manufacturing a photovoltaic module. Figure 43 This is a flowchart of a method for manufacturing photovoltaic modules in some embodiments. For example... Figure 43 As shown, the manufacturing method of photovoltaic modules includes: S1: Prepare battery string assembly 305.

[0319] S2: Arrange multiple battery string groups 305 along the second direction Y.

[0320] S3: In the first direction X, the interconnection part 23 is placed on the electrical connector 4, the interconnection part extends along the second direction Y, and in the third direction Z, the interconnection part 23 is located on the back surface of the battery string 305.

[0321] S4: Weld the interconnecting part 23 to the electrical connector 4 for fixation.

[0322] S5: An encapsulation layer 20 and a cover plate 10 are laid on the light-facing and back-facing surfaces of the battery string 305, and then laminated to form a laminate.

[0323] S6: Install a frame at the edge of the laminate to form a photovoltaic module.

[0324] Before or after step S3, the method for manufacturing photovoltaic modules further includes: S7: Weld the interconnecting part 23 to the second interconnecting strip 22.

[0325] In this embodiment, the second interconnecting strip 22 is located on the back surface of the solar cell 301, so that a part of the structure of the second interconnecting strip 22 is blocked by the solar cell 301. Without adjusting the size of the solar cell 301 and the second interconnecting strip 22 in the first direction X, the total size of the second interconnecting strip 22 and the solar cell string 303 in the first direction X can be reduced, thereby reducing the arrangement space of the second interconnecting strip 22 and the solar cell string 303, so as to arrange more solar cells 301 in a limited space, thereby increasing the screen ratio of the photovoltaic module and improving the output power of the photovoltaic module.

[0326] Figure 43 The example shows that step S7 is after step S4 and before step S5.

[0327] Figure 44 The flowcharts are shown in some other embodiments of the method for manufacturing photovoltaic modules. Figure 44 The example shows step S7 before step S3.

[0328] For electrical connectors that are either integral or separate structures, this application provides different manufacturing methods.

[0329] When the electrical connector is a split structure Figure 45 The flowchart for step S1 in some embodiments is as follows: Figure 45 As shown, step S1 includes: S11: Arrange the multiple battery cells 301 along the first direction X.

[0330] S12: Place the stringing strip 302 and the electrical connector 4 on the battery cell 301 and weld them to form a battery string 303.

[0331] S13: Arrange at least two battery strings 303 along the first direction X.

[0332] S14: Weld and fix the electrical connectors 4 of adjacent battery strings 303 to form a battery string group.

[0333] The adjacent electrical connectors 4 are the first electrical connector 43 and the second electrical connector 44 mentioned above. The first electrical connector 43 and the second electrical connector 44 can be arranged opposite each other along the first direction X, or opposite each other along the second direction Y, or have an overlapping part in the third direction Z.

[0334] Figure 46 for Figure 45 The steps in the flowcharts of some embodiments, such as Figure 46 As shown, prior to step S12, the photovoltaic module manufacturing method further includes: S01: The end of the electrical connector 4 is flattened to form an electrical connection portion 42. The part of the electrical connector 4 that is not flattened is the electrical connection body 41. In the first direction X, the electrical connection portions 42 of adjacent electrical connectors 4 are the first connection segment 421 and the second connection segment 422 mentioned above.

[0335] Following step S01, step S12 includes: The electrical connection body 41 is placed on the battery cell 301 and welded to form a battery string 303.

[0336] Step S14 includes: The first connecting segment 421 and the second connecting segment 422 are connected and fixed.

[0337] When the electrical connector is a one-piece structure, Figure 47 The flowchart for step S1 in some embodiments is as follows: Figure 47 As shown, step S1 includes: S15: Arrange multiple battery cells 301 along the first direction X.

[0338] S16: Place the stringing strip 302 on the battery cell 301 and weld it to form a battery string 303.

[0339] S17: Arrange at least two battery strings 303 along the first direction X.

[0340] S18: In the first direction X, place the two ends of the electrical connector 4 on the adjacent battery string 303 respectively and weld them to form a battery string group 305.

[0341] Figure 48 for Figure 47 The steps in the flowcharts of some embodiments, such as Figure 48 As shown, prior to step S18, the photovoltaic module manufacturing method further includes: S02: The middle part of the electrical connector 4 is flattened to form the electrical connector part 42, and the part of the electrical connector that is not flattened is the electrical connector body 41.

[0342] Following step S01, step S18 includes: The electrical connection body 41 is placed on the adjacent battery strings 303 and welded to fix them.

[0343] When the backlight surface of the battery cell 301 is provided with a separator 6, the separator 6 can be fixed to the battery string 303 first, and then the battery string 303 can be welded into the battery string assembly 305. Alternatively, the battery string 303 can be welded into the battery string assembly 305 first, and then the separator 6 can be fixed to the battery string assembly 305.

[0344] by Figure 48Taking the process shown as an example, Figure 49 A flowchart of part of step S1 in some other embodiments, such as Figure 49 As shown, after step S16 and before step S17, step S1 includes: S03: Place the separator 6 on the backlight side of the battery string 303.

[0345] S04: The separator 6 is fixed to the battery string 303 by hot stamping process.

[0346] by Figure 48 Taking the process shown as an example, Figure 50 The flowchart for step S1 in some embodiments is as follows: Figure 50 As shown, after step S3 and before step S4, the method for manufacturing photovoltaic modules further includes: S05: Place the separator 6 on the back side of the battery string 305.

[0347] S06: The separator 6 is fixed to the battery string 305 by hot stamping process.

[0348] In steps S03 and S05 above, the specific steps of the hot stamping process can be as follows: Hot air is used to press the separator 6 so that it is fixed on the battery cell 301.

[0349] Alternatively, the specific steps of the hot stamping process can be as follows: Infrared lamps are used to irradiate the insulating component 6, which fixes the insulating component 6 onto the battery cell 301.

[0350] The embodiments of this application do not impose special limitations on the specific steps of the hot stamping process.

[0351] In summary, in the photovoltaic module manufacturing method provided in this application embodiment, the interconnecting part 23 can be fixed to the battery string group 305 first, and then the second interconnecting strip 22 can be connected and fixed to the interconnecting part 23. Alternatively, the interconnecting part 23 and the second interconnecting strip 22 can be connected and fixed as a whole first, and then this whole can be fixed to the battery string group 305.

[0352] The separator 6 can be fixed to the battery string 303 first, and then the battery string 303 can be connected to form the battery string group 305. Alternatively, the battery string 303 can be connected to form the battery string group 305 first, and then the separator 6 can be fixed to the battery string group 305.

[0353] It should be noted that if the battery string 303 is first connected to form the battery string group 305, and then the interconnecting part 23, the second interconnecting strip 22 and the spacer 6 are fixed to the battery string group 305, then the following two steps are possible: The first method involves fixing the separator 6 to the battery string assembly 305, and then fixing the interconnecting part 23 and the second interconnecting strip 22 to the battery string assembly.

[0354] The second method involves first connecting the interconnecting part 23, the second interconnecting strip 22, and the isolation component 6 into a whole, and then connecting this whole battery string 305.

[0355] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A photovoltaic module, characterized in that, The photovoltaic module includes: Multiple battery string groups arranged along a second direction, the battery string group including at least two battery strings arranged along a first direction, the battery string including multiple battery cells and string bonding strips, the first direction intersecting the second direction; The second busbar is located on one or both sides of the battery string in the first direction; The connecting part, in the third direction, is located on the side of the second busbar facing the battery cell. The second busbar and the string welding strip are electrically connected through the connecting part, and adjacent battery strings are electrically connected through the second busbar. The second busbar is located on the back surface of the battery string, and in the third direction, the second busbar partially overlaps with the battery cell.

2. The photovoltaic module according to claim 1, characterized in that, The connecting part is fixed to the second busbar by welding or hot pressing; Alternatively, the second busbar and the connecting part are integrally formed.

3. The photovoltaic module according to claim 1, characterized in that, The second busbar includes a first edge and a second edge arranged along the first direction. In the first direction, the first edge is located on the side of the second busbar facing the battery string, and the second edge is located on the side of the second busbar away from the battery string. On the third-party direction, the edge of the connecting portion is aligned with the second edge.

4. The photovoltaic module according to claim 3, characterized in that, In the first direction, the width of the second busbar is H1, the width of the connecting part is H2, and 1.3 < H1 / H2 ≤ 75; In the second direction, the length of the connecting portion is less than the length of the second busbar.

5. The photovoltaic module according to claim 4, characterized in that, In the second direction, a gap is left between the end of the connecting portion and the end of the second busbar; The gap in the second direction has a dimension of H3, where 20mm ≤ H3 ≤ 50mm, or 0mm ≤ H3 ≤ 5mm.

6. The photovoltaic module according to claim 1, characterized in that, The string welding strip includes an edge welding strip, which includes a first body and a second body arranged along the first direction. The first body is electrically connected to the battery cell, and the second body is electrically connected to the connecting portion. In the second direction, the width of the second body is greater than the width of the first body.

7. The photovoltaic module according to claim 6, characterized in that, In the third direction, the thickness of the second body is less than the thickness of the first body.

8. The photovoltaic module according to claim 7, characterized in that, The edge solder strip is located on the light-facing or back-facing side of the battery cell; When the edge solder strip is located on the light-facing surface of the battery cell, in the third direction, the distance between the light-facing surface of the first body and the back-light-facing surface of the battery cell is L1, the distance between the light-facing surface of the second busbar and the back-light-facing surface of the battery cell is L2, the thickness of the connecting part is L3, L2≤L3<L1, or L2<L3≤L1. When the edge solder strip is located on the back surface of the battery cell, in the third direction, the distance between the light-facing surface of the first body and the light-facing surface of the second busbar is L4, the distance between the back surface of the first body and the light-facing surface of the second busbar is L5, the thickness of the connecting part is L6, L5≤L6<L4, or L5<L6≤L4.

9. The photovoltaic module according to any one of claims 1 to 8, characterized in that, In the first direction, the connecting part is kept at a preset distance from the edge of the battery cell, and the distance between the connecting part and the edge of the battery cell is less than or equal to 1.5 mm.

10. The photovoltaic module according to any one of claims 1 to 8, characterized in that, The cross-sectional shape of the connecting part is rectangular.

11. The photovoltaic module according to any one of claims 1 to 8, characterized in that, The photovoltaic module also includes an insulating strip, which is located between the second busbar and the solar cell in the third direction.

12. The photovoltaic module according to claim 11, characterized in that, In the first direction, the insulating strip extends toward the outside of the battery cell in the direction toward the connection portion.

13. The photovoltaic module according to claim 12, characterized in that, In the first direction, the insulating strip is in contact with the connecting portion, or there is a gap between the insulating strip and the connecting portion.

14. The photovoltaic module according to claim 11, characterized in that, In the second direction, the number of insulating strips is one; Alternatively, in the second direction, there may be multiple insulating strips, each corresponding to a battery string. Alternatively, in the second direction, there may be multiple insulating strips, with one insulating strip connected to at least two battery string groups.

15. A method for manufacturing a photovoltaic module, characterized in that, The method for manufacturing the photovoltaic module includes: Prepare a battery string assembly, the battery string assembly comprising at least two battery strings arranged along a first direction, the battery string comprising multiple battery cells and string bonding strips; Multiple battery string groups are arranged along a second direction, wherein the first direction intersects the second direction; In the first direction, the connecting part is placed on one or both sides of the battery string group, the connecting part extends along the second direction, and in the third direction, the connecting part is located on the back surface of the battery string group; The connecting part is welded and fixed to the welding strip; An encapsulation layer and a cover plate are laid on the light-facing and back-facing surfaces of the battery string assembly, and then laminated and fixed to form a laminate. A frame is installed along the edge of the laminate to form a photovoltaic module; Before or after the step of placing the connecting portion on one or both sides of the battery string, the method of manufacturing the photovoltaic module further includes: After welding and fixing the connecting part to the second busbar and welding and fixing the connecting part to the string welding strip, the second busbar is located on the back surface of the battery string group, and in the third direction, the second busbar partially overlaps with the battery cell.

16. The method for manufacturing a photovoltaic module according to claim 15, characterized in that, The string bonding strip includes edge bonding strips. Prior to the step of preparing the cell string assembly, the method for manufacturing the photovoltaic module includes: The ends of the edge weld strips are flattened to form a second body; The step of welding and fixing the connecting part to the welding strip includes: The connecting part is welded and fixed to the second body.

17. The method for manufacturing a photovoltaic module according to claim 15, characterized in that, The steps for preparing a battery string include: Arrange the multiple battery cells along the first direction; The string welding strip is placed on the battery cell and welded to form the battery string; At least two of the battery strings are arranged along the first direction; The battery string groups are formed by welding the wire strips of adjacent battery strings together.

18. The method for manufacturing a photovoltaic module according to claim 15, characterized in that, The wire bonding strip includes a first bonding strip and a second bonding strip, and the steps for preparing the battery string assembly include: Arrange the multiple battery cells along the first direction; The first solder strip is placed on the battery cell and welded to form the battery string; At least two of the battery strings are arranged along the first direction; In the first direction, the two ends of the second solder strip are respectively placed on the adjacent battery strings and welded to form the battery string group.

19. The method for manufacturing a photovoltaic module according to claim 17 or 18, characterized in that, Before the step of arranging at least two of the battery strings along the first direction, the method of manufacturing the photovoltaic module further includes: An insulating strip is placed on the battery string, with the third direction facing upwards and the insulating strip located on the back side of the battery cell; The insulating strip is fixed to the battery string by a hot-spinning process.

20. The method for manufacturing a photovoltaic module according to any one of claims 15 to 18, characterized in that, Before the step of welding and fixing the connecting portion to the string strip, the method for manufacturing the photovoltaic module further includes: An insulating strip is placed on the battery string, with the third direction facing upwards and the insulating strip located on the back side of the battery cell; The insulating strip is fixed to the battery string using a hot-spinning process.

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