Solar cell and photovoltaic module

Abstract

The invention relates to a solar cell and a photovoltaic module. The solar cell comprises a cell sheet body; the plurality of first grid lines are arranged on one side of the battery piece body, and the plurality of first grid lines are arranged at intervals along a first direction; the at least one first connecting pad group comprises a plurality of first connecting pads which are in one-to-one correspondence with the plurality of first grid lines; each first connecting pad is arranged on the corresponding first grid line; wherein at least part of the first connecting pads comprise at least two first sub-connecting pads which are arranged at intervals along the extension direction of the first grid line. According to the embodiment of the invention, the consumption of slurry can be reduced, and the manufacturing cost of the solar cell is reduced.

Description

Technical Field

[0001] The present application relates to the technical field of solar photovoltaic cells, and in particular to a solar cell and a photovoltaic module. Background Art

[0002] Faced with the serious problem of depletion of non-renewable energy worldwide, countries are vigorously advocating the development of renewable clean energy. Among them, the photovoltaic industry that can convert solar energy into electrical energy has gained unprecedented development opportunities.

[0003] In the current solar cell manufacturing technology, busbar-free technology has become an important direction for the development of solar cells due to its advantages of reducing the shading area, reducing stress concentration, and facilitating heat dissipation. The grid lines of busbar-free solar cells are connected to the welding ribbon through silver electrodes in the form of a dot matrix. However, the manufacturing cost of this type of solar cell is relatively high. Summary of the invention

[0004] Based on this, it is necessary to provide a solar cell and a photovoltaic module to address the above problems.

[0005] In a first aspect, an embodiment of the present application provides a solar cell, comprising:

[0006] Battery cell body;

[0007] A plurality of first grid lines are arranged on one side of the battery cell body, and the plurality of first grid lines are arranged at intervals along a first direction;

[0008] At least one first connection pad group, the first connection pad group comprising a plurality of first connection pads corresponding to the plurality of first gate lines one by one; each of the first connection pads is disposed on a corresponding one of the first gate lines;

[0009] Wherein, at least part of the first connection pads include at least two first sub-connection pads arranged at intervals along the extending direction of the first gate line.

[0010] In one of the embodiments, the first connection pad further includes a first connection layer formed on the first sub-connection pad;

[0011] The first connection layer is located on a side of the first sub-connection pad away from the first gate line.

[0012] In one embodiment, the first connection layer includes a conductive adhesive or a metal plating layer.

[0013] In one embodiment, the orthographic projection of a portion of the first gate line between two adjacent first sub-connection pads on the battery cell body is a first orthographic projection;

[0014] The first connection pad further includes a first protective layer formed on the first gate line, and a positive projection of the first protective layer on the battery cell body covers at least a part of the first positive projection.

[0015] In one embodiment, the first connection layer includes a conductive adhesive, and an outer contour of a positive projection of the first sub-connection pad on the battery cell body is located outside an outer contour of a positive projection of the corresponding first connection layer on the battery cell body.

[0016] In the same first connection pad, the first protective layer is disposed between two first connection layers respectively corresponding to two adjacent first sub-connection pads, and the first protective layer is located on a side of the first sub-connection pad away from the battery cell body.

[0017] In one embodiment, a distance between a surface of the first protective layer close to the battery cell body and a surface of the first protective layer away from the battery cell body is a first distance;

[0018] A distance between a surface of the first connection layer close to the battery cell body and a surface of the first connection layer away from the battery cell body is a second distance;

[0019] The first distance is less than the second distance.

[0020] In one embodiment, a positive projection of the first sub-connection pad connected to the first protective layer on the battery cell body and a positive projection of the first protective layer on the battery cell body have an overlapping area; a dimension of the overlapping area in an extending direction of the first gate line is L1;

[0021] Wherein, L1 satisfies the following relationship: 0mm < L1 ≤ 0.2mm; and / or, a dimension of the first gate line in the first direction is W1, and L1 and W1 satisfy the following relationship: 3W1 ≤ L1 ≤ 5W1.

[0022] In one embodiment, the first connection layer includes a metal coating, and the metal coating covers a surface of the first sub-connection pad away from the battery cell body.

[0023] The first protective layer is disposed between two adjacent first sub-connection pads, and the first protective layer is in contact with the first gate line.

[0024] In one embodiment, a distance between a surface of the first protective layer away from the battery cell body and the battery cell body is less than a distance between a surface of the first connection layer away from the battery cell body and the battery cell body.

[0025] In one embodiment, the first connection pad includes three of the first sub-connection pads;

[0026] Among them, the size of the first sub-connection pad located in the middle along the extension direction of the first gate line is smaller than the sizes of the remaining first sub-connection pads along the extension direction of the first gate line.

[0027] In one embodiment, the first gate line includes n first sub-segments arranged at intervals along its own extension direction, and the solar cell includes m first connection pad groups, where m and n satisfy the following relationship: n = m + 1;

[0028] At the critical point of any two adjacent first sub-segments, one first connection pad group is provided; among them, at least one of the first sub-connection pads of the first connection pad group is provided on one of the first sub-segments, and at least one of the first sub-connection pads of the first connection pad group is provided on the other first sub-segment.

[0029] In one embodiment, the solar cell further includes:

[0030] A plurality of second gate lines are provided on the battery cell body, and the plurality of second gate lines are arranged at intervals along the first direction;

[0031] At least one second connection pad group, including a plurality of second connection pads corresponding one-to-one to the plurality of second gate lines; each second connection pad is provided on a corresponding one of the second gate lines;

[0032] Among them, at least some of the second connection pads include at least two second sub-connection pads arranged at intervals along the extension direction of the second gate line.

[0033] In one embodiment, the plurality of second gate lines are provided on the side of the battery cell body close to the first gate line;

[0034] The first gate line and the second gate line are arranged alternately along the first direction, and the first connection pad group and the second connection pad group are arranged alternately along the second direction;

[0035] The second direction is parallel to the extension direction of the first gate line and / or the second gate line.

[0036] In one embodiment, the solar cell further includes:

[0037] At least one first insulating layer group, the first insulating layer group including a plurality of first insulating layers corresponding one-to-one to the plurality of first gate lines; each first insulating layer is provided on a corresponding one of the first gate lines;

[0038] At least one second insulating layer group, the second insulating layer group including a plurality of second insulating layers corresponding one by one to the plurality of second gate lines; each of the second insulating layers is disposed on a corresponding one of the second gate lines;

[0039] Wherein, the first insulating layer group corresponds one by one to the second connection pad group, and in the corresponding first insulating layer group and second connection pad group, the first insulating layer and the second connection pad are alternately arranged along the first direction;

[0040] The second insulating layer group corresponds one by one to the first connection pad group, and in the corresponding second insulating layer group and first connection pad group, the second insulating layer and the first connection pad are alternately arranged along the first direction.

[0041] In one embodiment, in the same first connection pad group, the distance between two adjacent first connection pads is L2; the dimension of the first gate line along the first direction is W1, and L2 and W1 satisfy the following relationship: 3W1 ≤ L2 ≤ 18W1;

[0042] And / or, the dimension of the first connection pad along the extension direction of the first gate line is L3, the dimension of the second connection pad along the extension direction of the second gate line is L4, and the dimension of the first gate line along the first direction is W1; L3 and W1 satisfy the following relationship: 20W1 ≤ L3 ≤ 40W1; L4 and W1 satisfy the following relationship: 20W1 ≤ L4 ≤ 40W1;

[0043] And / or, the dimension of the first sub-connection pad along the first direction is L5, the dimension of the second sub-connection pad along the first direction is L6, and the spacing between two adjacent first gate lines and second gate lines is L7; L5 and L7 satisfy the following relationship: 0.1L7 ≤ L5 ≤ 0.5L7; L6 and L7 satisfy the following relationship: 0.1L7 ≤ L6 ≤ 0.5L7;

[0044] And / or, in the same second connection pad group, the distance between two adjacent second connection pads is L8; the dimension of the second gate line along the first direction is W2, and L8 and W2 satisfy the following relationship: 3W2 ≤ L8 ≤ 18W2.

[0045] In one embodiment, the second connection pad further includes a second connection layer formed on the second sub-connection pad;

[0046] The second connection layer is located on a side of the second sub-connection pad away from the first gate line.

[0047] In one embodiment, the second connection layer includes a conductive adhesive or a metal plating layer.

[0048] In one embodiment, the portion of the second gate line located between two adjacent second sub-connection pads has a second orthographic projection on the cell body;

[0049] The second connection pad further includes a second protective layer formed on the second gate line, and the orthographic projection of the second protective layer on the cell body covers at least a part of the second orthographic projection.

[0050] In one embodiment, the second connection layer includes a conductive adhesive, and the outer contour of the orthographic projection of the second sub-connection pad on the cell body is located outside the outer contour of the orthographic projection of the corresponding second connection layer on the cell body;

[0051] In the same second connection pad, the second protective layer is disposed between two second connection layers respectively corresponding to two adjacent second sub-connection pads, and the second protective layer is located on the side of the second sub-connection pad away from the cell body.

[0052] In one embodiment, the distance between the surface of the second protective layer close to the cell body and the surface of the second protective layer away from the cell body is a third distance;

[0053] The distance between the surface of the second connection layer close to the cell body and the surface of the second connection layer away from the cell body is a fourth distance;

[0054] The third distance is less than the fourth distance.

[0055] In one embodiment, the orthographic projection of the second sub-connection pad connected to the second protective layer on the cell body and the orthographic projection of the second protective layer on the cell body have an overlapping area; the dimension of the overlapping area in the extending direction of the second gate line is L9;

[0056] Wherein, L9 satisfies the following relationship: 0mm < L9 ≤ 0.2mm; and / or, the dimension of the second gate line in the first direction is W2, and L9 and W2 satisfy the following relationship: 3W2 ≤ L9 ≤ 5W2.

[0057] In one embodiment, the second connection layer is a metal coating, and the metal coating covers the surface of the second sub-connection pad away from the cell body;

[0058] The second protective layer is disposed between two adjacent second sub-connection pads, and the second protective layer is in contact with the second gate line.

[0059] In one embodiment, the distance between the surface of the second protective layer away from the battery cell body and the battery cell body is less than the distance between the surface of the second connection layer away from the battery cell body and the battery cell body.

[0060] In one embodiment, the second connection pad includes three second sub-connection pads;

[0061] Among them, the dimension of the middle second sub-connection pad along the extension direction of the second grid line is less than the dimensions of the remaining second sub-connection pads along the extension direction of the second grid line.

[0062] In one embodiment, the second grid line includes n second sub-segments arranged at intervals along its own extension direction, and the solar cell includes m second connection pad groups, and m and n satisfy the following relationship: n = m + 1;

[0063] A second connection pad group is provided at the critical point of any two adjacent second sub-segments; among them, at least one second sub-connection pad of the second connection pad group is provided on one second sub-segment, and at least one second sub-connection pad of the second connection pad group is provided on another second sub-segment.

[0064] In one embodiment, the multiple second grid lines are provided on the side of the battery cell body away from the first grid line.

[0065] In a second aspect, an embodiment of the present application provides a photovoltaic module, including:

[0066] The solar cell in any embodiment of the first aspect;

[0067] A first welding strip connected to the first sub-connection pad of the first connection pad group.

[0068] In one embodiment, the photovoltaic module further includes a second welding strip, and the second welding strip is connected to the second sub-connection pad of the second connection pad group of the solar cell.

[0069] The solar cell and the photovoltaic module provided by the embodiments of the present application, by providing the first connection pad group and setting the first connection pad as at least two first sub-connection pads arranged at intervals, the first grid line can be connected to the first welding strip through the first sub-connection pad. In this way, it is equivalent to dividing the first connection pad into multiple first sub-connection pads arranged at intervals, and no paste is consumed in the gap between two adjacent first sub-connection pads. Thus, compared with a whole solder pad (i.e., connection pad) in the related art, under the condition of a certain external dimension, the embodiments of the present application can reduce the amount of paste used and reduce the manufacturing cost of the solar cell. Description of the Drawings

[0070] To more clearly illustrate the technical solutions in the embodiments or exemplary embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments or exemplary embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0071] Figure 1 Schematic diagram of a solar cell provided in an embodiment of the present application.

[0072] Figure 2 Schematic diagram of another solar cell provided in an embodiment of the present application.

[0073] Figure 3 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0074] Figure 4 For Figure 3 Schematic diagram of the connection of the shown solar cell, the first solder ribbon, and the second solder ribbon.

[0075] Figure 5 For Figure 4 Cross-sectional schematic diagram of the A-A cross-section in

[0076] Figure 6 For Figure 4 Cross-sectional schematic diagram of the B-B cross-section in

[0077] Figure 7 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0078] Figure 8 For Figure 7 Schematic diagram of the connection of the first connection pad and the first solder ribbon in

[0079] Figure 9 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0080] Figure 10 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0081] Figure 11 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0082] Figure 12 Schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0083] Figure 13 Cross-sectional structure schematic diagram of yet another solar cell provided in an embodiment of the present application.

[0084] Reference numerals: 10, solar cell; 11, cell body; 12, first grid line; 121, first sub-segment; 13, first connection pad group; 131, first connection pad; 1311, first sub-connection pad; 1312, first connection layer; 1313, first protective layer; 14, second grid line; 141, second sub-segment; 15, second connection pad group; 151, second connection pad; 1511, second sub-connection pad; 1512, second connection layer; 1513, second protective layer; 16, first insulation layer group; 161, first insulation layer; 17, second insulation layer group; 171, second insulation layer; 20, first solder tape; 30, second solder tape; 40, filling glue. Detailed implementation manners

[0085] To make the above objects, features, and advantages of the present application more apparent and understandable, the following will describe in detail the specific implementation manners of the present application with reference to the accompanying drawings. Many specific details are set forth in the following description in order to fully understand the present application. However, the present application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the connotation of the present application. Therefore, the present application is not limited by the specific embodiments disclosed below.

[0086] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0087] It should be understood that when an element or layer is referred to as "on", "adjacent to", "connected to", or "coupled to" another element or layer, it can be directly on, adjacent to, connected, or coupled to the other element or layer, or there may be intervening elements or layers. In contrast, when an element is referred to as "directly on", "directly adjacent to", "directly connected to", or "directly coupled to" another element or layer, there are no intervening elements or layers. It should be understood that although the terms first, second, third, etc. may be used to describe various elements, components, regions, layers, doping types, and / or parts, these elements, components, regions, layers, doping types, and / or parts should not be limited by these terms. These terms are only used to distinguish one element, component, region, layer, doping type, or part from another element, component, region, layer, doping type, or part. Therefore, without departing from the teachings of this application, the first element, component, region, layer, doping type, or part discussed below may be denoted as the second element, component, region, layer, or part.

[0088] Spatial relationship terms such as "under", "below", "lower", "beneath", "above", "upper", etc. may be used herein to describe the relationship of one element or feature shown in the figures to other elements or features. It should be understood that, in addition to the orientations shown in the figures, spatial relationship terms also encompass different orientations of the device in use and operation. For example, if the device in the figures is flipped, an element or feature described as "under other elements" or "beneath them" or "underneath them" will be oriented "above" the other elements or features. Thus, the exemplary terms "under" and "beneath" can include both the upper and lower orientations. Additionally, the device may also assume other orientations (such as, for example, rotated 90 degrees or other orientations), and the spatial descriptors used herein are to be interpreted accordingly.

[0089] As used herein, the singular forms "a", "an", and "the" may also include the plural forms unless the context clearly dictates otherwise. It should also be understood that the terms "comprises / include" or "has" etc. specify the presence of the stated features, integers, steps, operations, components, parts, or combinations thereof, but do not preclude the presence or addition of one or more other features, integers, steps, operations, components, parts, or combinations thereof. Also, in this specification, the term "and / or" includes any and all combinations of the related listed items.

[0090] Embodiments of the application are described herein with reference to cross-sectional views that are schematic illustrations of ideal embodiments (and intermediate structures) of the present application, and variations in the illustrated shapes due to, for example, manufacturing techniques and / or tolerances can be expected. Thus, embodiments of the present application should not be limited to the specific shapes of the regions shown herein, but include shape deviations due to, for example, manufacturing techniques. The regions shown in the figures are substantially schematic, and their shapes do not represent the actual shapes of the regions of the device and do not limit the scope of the present application.

[0091] As described in the background art, the grid lines of the main-gridless solar cell are connected to the bus bar through a dot matrix form of silver electrodes. Since a large amount of silver electrodes need to be printed on each grid line, the consumption of silver paste is relatively large, increasing the manufacturing cost of the solar cell.

[0092] In view of the above problems, an embodiment of the present application provides a solar cell and a photovoltaic module. By providing a first connection pad group, a first solder ribbon is connected to a corresponding first grid line through each first connection pad of the first connection pad group. By setting the first connection pad as at least two first sub-connection pads arranged at intervals, the first grid line can be connected to the first grid line through the first sub-connection pad. In this way, it is equivalent to dividing the first connection pad into multiple first sub-connection pads arranged at intervals, and no paste is consumed in the gap between two adjacent first sub-connection pads. Thus, compared with a single-piece solder pad (i.e., connection pad) in the related art, when the external dimensions are fixed, the embodiment of the present application can reduce the amount of paste used and reduce the manufacturing cost of the solar cell.

[0093] In a first aspect, referring to Figure 1 , Figure 2 and Figure 3 shown, an embodiment of the present application provides a solar cell 10. The solar cell 10 can be a BC (Back Contact) cell, a TOPCon (Tunnel Oxide Passivated Contact) cell, an HJT (Heterojunction with Intrinsic Thin-film) cell, etc. It should be noted that the solar cell 10 is a single-sided main-gridless cell or a double-sided main-gridless cell.

[0094] Specifically, the solar cell 10 includes a cell body 11, a plurality of first grid lines 12, and at least one first connection pad group 13. The plurality of first grid lines 12 are disposed on one side of the cell body 11, and the plurality of first grid lines 12 are arranged at intervals along the first direction X. The first connection pad group 13 includes a plurality of first connection pads 131 corresponding to the plurality of first grid lines 12 one by one; each first connection pad 131 is disposed on a corresponding first grid line 12.

[0095] Among them, at least some of the first connection pads 131 include at least two first sub-connection pads 1311 arranged at intervals along the extension direction of the first grid line 12.

[0096] In an example, the first grid line 12 extends along the second direction Y. In other words, the extension direction of the first grid line 12 is parallel to the second direction Y. The second direction Y intersects the first direction X. The first grid line 12 can be a positive grid line or a negative grid line.

[0097] It should be noted that, please refer to Figure 4As shown, the same first connection pad group 13 is used to connect with the same first welding ribbon 20, so as to realize the connection between the first welding ribbon 20 and multiple first gate lines 12. Specifically, the first welding ribbon 20 is connected to the two first sub-connection pads 1311 on the first gate line 12, so as to realize the connection between the first welding ribbon 20 and the first gate line 12.

[0098] It is understandable that the number of the first connection pad groups 13 can be multiple. When the number of the first connection pad groups 13 is multiple, all the first connection pad groups 13 are arranged at intervals along the second direction Y, and each first connection pad group 13 is connected to a first welding strip 20.

[0099] The solar cell 10 provided in the embodiment of the present application is provided with a first connection pad group 13, and the first connection pad 131 is provided as at least two first sub-connection pads 1311 arranged at intervals, and the first grid line 12 can be connected to the first welding strip 20 through the first sub-connection pad 1311. In this way, it is equivalent to dividing the first connection pad 131 into a plurality of first sub-connection pads 1311 arranged at intervals, and the slurry is not consumed in the gap between two adjacent first sub-connection pads 1311. In this way, compared with a whole pad in the related art, when the outer dimensions of the pad are consistent with the outer dimensions (such as length and width) of the first connection pad 131, the embodiment of the present application can reduce the amount of slurry used, thereby reducing the manufacturing cost of the solar cell 10.

[0100] In one embodiment, if Figure 3 As shown, the first connection pad 131 further includes a first connection layer 1312 formed on the first sub-connection pad 1311. The first connection layer 1312 is located on a side of the first sub-connection pad 1311 away from the first gate line 12. By providing the first connection layer 1312, the connection tightness and connection stability between the first sub-connection pad 1311 and the first welding ribbon 20 can be enhanced.

[0101] It is understandable that in the same first connection pad 131 , the number of the first connection layers 1312 and the number of the first sub-connection pads 1311 may be the same. Specifically, one first connection layer 1312 is disposed on each first sub-connection pad 1311 .

[0102] In one embodiment, the first connection layer 1312 includes a conductive adhesive or a metal plating layer.

[0103] When the first connection layer 1312 is a conductive adhesive, the first connection layer 1312 can bond the first soldering tape 20 to the first sub-connection pad 1311, which is beneficial to improving the connection stability. Specifically, the first soldering tape 20, the first connection layer 1312 (conductive adhesive) and the first sub-connection pad 1311 can be connected by lamination.

[0104] When the first connection layer 1312 is a metal coating, the first connection layer 1312 can be connected to the first solder strip 20 by welding. In one example, the metal coating can be a tin coating.

[0105] In one embodiment, the portion of the first gate line 12 between two adjacent first sub-connection pads 1311 has a first orthographic projection on the cell body 11. The first connection pad 131 further includes a first protective layer 1313 formed on the first gate line 12, and the orthographic projection of the first protective layer 1313 on the cell body 11 covers at least a portion of the first orthographic projection. By providing the first protective layer 1313, the first gate line 12 between the two first sub-connection pads 1311 can be protected, preventing the first solder strip 20 from melting the first gate line 12 during the welding process, thereby affecting the efficiency of the solar cell 10.

[0106] In one embodiment, the material of the first protective layer 1313 is an insulating material. The insulating material can be epoxy resin, phenolic resin, silicone rubber, polyimide, polyvinyl butyral ester, etc. The specific type of the insulating material is not particularly limited in the embodiments of the present application.

[0107] In one embodiment, as Figure 3 shown, the first connection layer 1312 includes a conductive adhesive. The outer contour of the orthographic projection of the first sub-connection pad 1311 on the cell body 11 is located outside the outer contour of the orthographic projection of the corresponding first connection layer 1312 on the cell body 11. That is: in a plan view, the area of the first connection layer 1312 is smaller than the area of the first sub-connection pad 1311.

[0108] Further, in the same first connection pad 131, the first protective layer 1313 is provided between two first connection layers 1312 corresponding to two adjacent first sub-connection pads 1311 respectively, and the first protective layer 1313 is located on the side of the first sub-connection pad 1311 away from the cell body 11. That is: both ends of the first protective layer 1313 in the second direction Y are respectively laid on the two first sub-connection pads 1311. In this way, not only can the first protective layer 1313 protect the first gate line 12 between the two first sub-connection pads 1311, but also the coverage area of the first protective layer 1313 can be reduced, avoiding the influence of the first protective layer 1313 on the connection between the first solder strip 20 and the first sub-connection pad 1311.

[0109] It can be understood that the shape of the conductive adhesive can be square, circular, crescent-shaped or other shapes.

[0110] It should be noted that the larger the area of the conductive adhesive, the higher the stack height after the conductive adhesive is cured. Figure 3Taking the embodiments in [description] as an example, in the embodiments of the present application, the conductive adhesive is designed as at least two small dots. Compared with a whole piece of conductive adhesive in the related art, the area of the conductive adhesive is reduced, and the stacking height after curing of the conductive adhesive is reduced, thereby reducing the lamination risk caused by the stacking height of the conductive adhesive. At the same time, the solder strip is connected to at least two conductive adhesives, which can ensure the current collection effect. On the other hand, there are burrs on the surface of the conductive adhesive after curing. After the stacking height of the conductive adhesive is reduced, the risk of the battery cell body 11 being punctured and cracked after lamination can also be reduced, improving the component yield.

[0111] In one of the embodiments, the distance between the surface of the first protective layer 1313 close to the battery cell body 11 and the surface of the first protective layer 1313 far from the battery cell body 11 is the first distance. The distance between the surface of the first connection layer 1312 close to the battery cell body 11 and the surface of the first connection layer 1312 far from the battery cell body 11 is the second distance. Here, the first distance is the thickness of the first protective layer 1313, and the second distance is the thickness of the first connection layer 1312.

[0112] Specifically, the first distance is less than the second distance. In this way, it is equivalent to making the thickness of the first protective layer 1313 less than the thickness of the first connection layer 1312. In this way, it can prevent the first protective layer 1313 from raising the first solder strip 20, thereby affecting the close contact between the first solder strip 20 and the first connection layer 1312.

[0113] In one of the embodiments, as Figure 2 shown, the orthographic projection of the first sub-connection pad 1311 connected to the first protective layer 1313 on the battery cell body 11 and the orthographic projection of the first protective layer 1313 on the battery cell body 11 have an overlapping area; the dimension of the overlapping area along the extension direction of the first grid line 12 is L1. Here, L1 can be understood as the overlapping length of the first protective layer 1313 and the first sub-connection pad 1311.

[0114] Among them, L1 satisfies the following relationship: 0mm < L1 ≤ 0.2mm. Exemplarily, L1 can be 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm or between any two of the above values. In this way, not only can the first protective layer 1313 protect the first grid line 12 between the two first sub-connection pads 1311, but also the coverage area of the first protective layer 1313 can be reduced, avoiding the influence of the first protective layer 1313 on the connection between the first solder strip 20 and the first sub-connection pad 1311.

[0115] In one embodiment, the dimension of the first gate line 12 along the first direction X is W1, and L1 and W1 satisfy the following relationship: 3W1 ≤ L1 ≤ 5W1. Exemplarily, L1 can be 3 times W1, 4 times W1, 4.5 times W1, 5 times W1, etc. In this way, not only can the first protective layer 1313 protect the first gate line 12 between the two first sub-connection pads 1311, but also the coverage area of the first protective layer 1313 can be reduced, avoiding the influence of the first protective layer 1313 on the connection between the first solder ribbon 20 and the first sub-connection pad 1311.

[0116] It should be noted that for the connection schematic of the first solder ribbon 20 and the first connection pad group 13, please refer to Figure 4 , Figure 5 and Figure 6 as shown. The specific connection details will be described in detail below.

[0117] In one of the embodiments, referring to Figure 7 and Figure 8 as shown, the first connection layer 1312 includes a metal coating, and the metal coating covers the surface of the first sub-connection pad 1311 away from the battery cell body 11. In one example, the metal coating covers the entire upper surface of the first sub-connection pad 1311.

[0118] Furthermore, the first protective layer 1313 is disposed between two adjacent first sub-connection pads 1311, and the first protective layer 1313 is in contact with the first gate line 12. In this way, it is avoided to set the first protective layer 1313 on the first sub-connection pad 1311, preventing the height of the first protective layer 1313 from being too high, so that the first solder ribbon 20 is lifted up and it is not easy for the first solder ribbon 20 to contact the first connection layer 1312.

[0119] In one of the embodiments, the distance between the surface of the first protective layer 1313 away from the battery cell body 11 and the battery cell body 11 is less than the distance between the surface of the first connection layer 1312 away from the battery cell body 11 and the battery cell body 11. In this way, it can prevent the first protective layer 1313 from lifting up the first solder ribbon 20, thereby affecting the close contact between the first solder ribbon 20 and the first connection layer 1312.

[0120] In one of the embodiments, as Figure 9 and Figure 10 shown, the first gate line 12 includes n first sub-segments 121 arranged at intervals along its own extending direction, that is: the first gate line 12 is a discontinuous gate line. The solar cell 10 includes m first connection pad groups 13, and m and n satisfy the following relationship: n = m + 1.

[0121] Specifically, a first connection pad group 13 is provided at the critical position of any two adjacent first sub-segments 121; wherein, at least one first sub-connection pad 1311 of the first connection pad group 13 is provided on one first sub-segment 121, and at least one first sub-connection pad 1311 of the first connection pad group 13 is provided on another first sub-segment 121.

[0122] It should be noted that when the first grid line 12 is a discontinuous grid line, the first protective layer 1313 may not need to be provided. Further, the first solder strip 20 can be directly welded and connected to the first connection sub-pad.

[0123] In one embodiment, referring to Figures 1 - 10 As shown, the solar cell 10 further includes a plurality of second grid lines 14 and at least one second connection pad group 15. The plurality of second grid lines 14 are provided on the battery chip body 11, and the plurality of second grid lines 14 are arranged at intervals along the first direction X. The second connection pad group 15 includes a plurality of second connection pads 151 corresponding one-to-one to the plurality of second grid lines 14; each second connection pad 151 is provided on a corresponding second grid line 14.

[0124] Wherein, at least part of the second connection pads 151 include at least two second sub-connection pads 1511 arranged at intervals along the extension direction of the second grid line 14.

[0125] In an example, the second grid line 14 extends along the second direction Y. In other words, the extension direction of the second grid line 14 is parallel to the second direction Y. The second grid line 14 can be a positive grid line or a negative grid line. If the first grid line 12 is a positive grid line, then the second grid line 14 is a negative grid line. If the first grid line 12 is a negative grid line, then the second grid line 14 is a positive grid line.

[0126] It should be noted that the same second connection pad group 15 is used to connect to the same second solder strip 30, so as to realize the connection between the second solder strip 30 and the plurality of second grid lines 14. Specifically, the second solder strip 30 is connected to two second sub-connection pads 1511 on the second grid line 14, so as to realize the connection between the second solder strip 30 and the second grid line 14.

[0127] It can be understood that the number of the second connection pad groups 15 can be multiple. When the number of the second connection pad groups 15 is multiple, all the second connection pad groups 15 are arranged at intervals along the second direction Y, and each second connection pad group 15 is connected to a second solder strip 30.

[0128] The above configuration is equivalent to dividing the second connection pad 151 into a plurality of second sub-connection pads 1511 arranged at intervals, and the slurry is not consumed in the gap between two adjacent second sub-connection pads 1511. In this way, compared with a whole pad in the related art, when the outer dimensions of the pad and the outer dimensions of the second connection pad 151 (such as length and width) are consistent, the embodiment of the present application can reduce the amount of slurry used, thereby reducing the manufacturing cost of the solar cell 10.

[0129] In one embodiment, a plurality of second grid lines 14 are arranged on one side of the cell body 11 close to the first grid lines 12, that is, the first grid lines 12 and the second grid lines 14 are arranged on the same side of the cell body 11. It can be understood that in this case, the first grid lines 12 and the second grid lines 14 are both arranged on the backlight side of the cell, and at this time, the solar cell 10 is a BC cell.

[0130] Furthermore, the first gate lines 12 and the second gate lines 14 are alternately arranged along the first direction X, and the first connection pad groups 13 and the second connection pad groups 15 are alternately arranged along the second direction Y. The second direction Y is parallel to the extension direction of the first gate lines 12 and / or the second gate lines 14, that is, the extension direction of at least one of the first gate lines 12 and the second gate lines 14 is parallel to the second direction Y.

[0131] In one embodiment, referring to Figure 2 , Figure 3 , Figure 4 , Figure 7 and Figure 10 As shown, the solar cell 10 further includes at least one first insulating layer group 16 and at least one second insulating layer group 17. The first insulating layer group 16 includes a plurality of first insulating layers 161 corresponding to the plurality of first grid lines 12 one by one; each first insulating layer 161 is disposed on a corresponding first grid line 12. The second insulating layer group 17 includes a plurality of second insulating layers 171 corresponding to the plurality of second grid lines 14 one by one; each second insulating layer 171 is disposed on a corresponding second grid line 14.

[0132] The first insulating layer group 16 corresponds to the second connection pad group 15 , and in the corresponding first insulating layer group 16 and second connection pad group 15 , the first insulating layers 161 and the second connection pads 151 are alternately arranged along the first direction X. The first insulating layer 161 can insulate the second welding strip 30 from the first gate line 12 .

[0133] The second insulating layer group 17 corresponds to the first connection pad group 13 one by one. In the corresponding second insulating layer group 17 and first connection pad group 13 , the second insulating layers 171 and the first connection pads 131 are alternately arranged along the first direction X. The second insulating layer 171 can insulate the first welding strip 20 from the second gate line 14 .

[0134] Here, it should be noted that the number of the first insulating layer groups 16 is the same as that of the second connection pad groups 15, and the number of the second insulating layer groups 17 is the same as that of the first connection pad groups 13.

[0135] In one embodiment, the first gate lines 12 and the second gate lines 14 are alternately arranged one by one along the first direction X, the first insulating layers 161 and the second connection pads 151 are alternately arranged one by one along the first direction X, and the second insulating layers 171 and the first connection pads 131 are alternately arranged one by one along the first direction X.

[0136] In one of the embodiments, referring to Figure 1 As shown, in the same first connection pad group 13, the distance between two adjacent first connection pads 131 is L2; the dimension of the first gate line 12 along the first direction X is W1, and L2 and W1 satisfy the following relationship: 3W1 ≤ L2 ≤ 18W1. Exemplarily, L2 can be 3 times W1, 6 times W1, 12 times W1, 18 times W1, etc. In this way, on the one hand, it can ensure that the first connection pad 131 and the first solder tape 20 have sufficient contact area to ensure the connection stability between the first solder tape 20 and the first connection pad 131; on the other hand, it can minimize the use of the paste, thereby reducing the manufacturing cost.

[0137] In one of the embodiments, referring to Figure 1 As shown, the dimension of the first connection pad 131 along the extension direction of the first gate line 12 is L3, the dimension of the second connection pad 151 along the extension direction of the second gate line 14 is L4, and the dimension of the first gate line 12 along the first direction X is W1; L3 and W1 satisfy the following relationship: 20W1 ≤ L3 ≤ 40W1; L4 and W1 satisfy the following relationship: 20W1 ≤ L4 ≤ 40W1. Exemplarily, L3 and L4 can be 20 times W1, 25 times W1, 35 times W1, 40 times W1, etc. In this way, the first connection pad 131 and the second connection pad 151 can have sufficient lengths to ensure that the first connection pad 131 and the first solder tape 20 have sufficient contact area, and the second connection pad 151 and the second solder tape 30 have sufficient contact area.

[0138] In one of the embodiments, W1 is between 25 μm and 35 μm.

[0139] In one of the embodiments, the ratio of L2 to L3 can be 0.2 - 0.4. In this way, the paste consumption can be saved by 7% - 15%.

[0140] In one of the embodiments, L2 is between 0.8 mm and 1.2 mm.

[0141] In one of the embodiments, referring to Figure 1As shown, the dimension of the first sub-connection pad 1311 along the first direction X is L5, the dimension of the second sub-connection pad 1511 along the first direction X is L6, and the spacing between adjacent first gate lines 12 and second gate lines 14 is L7; the relationship between L5 and L7 is as follows: 0.1L7 ≤ L5 ≤ 0.5L7; the relationship between L6 and L7 is as follows: 0.1L7 ≤ L6 ≤ 0.5L7. Exemplarily, L5 and L6 can be 0.1 times L7, 0.2 times L7, 0.25 times L7, 0.3 times L7, 0.5 times L7, etc. With the above settings, on the one hand, the amount of paste used can be minimized, thereby reducing the manufacturing cost; on the other hand, the first connection pad 131 and the second connection pad 151 can have sufficient widths to ensure that the first connection pad 131 has sufficient contact area with the first solder tape 20, and the second connection pad 151 has sufficient contact area with the second solder tape 30.

[0142] In one embodiment, referring to Figure 1 As shown, in the same second connection pad group 15, the distance between adjacent two second connection pads 151 is L8; the dimension of the second gate line 14 along the first direction X is W2, and the relationship between L8 and W2 is as follows: 3W2 ≤ L8 ≤ 18W2. Exemplarily, L8 can be 3 times W1, 6 times W1, 12 times W1, 18 times W1, etc. In this way, on the one hand, it can ensure that the second connection pad 151 has sufficient contact area with the second solder tape 30 to ensure the connection stability between the second solder tape 30 and the second connection pad 151; on the other hand, it can minimize the amount of paste used, thereby reducing the manufacturing cost.

[0143] In one embodiment, W2 is between 25 μm and 35 μm.

[0144] In one embodiment, the ratio of L8 to L4 can be 0.2 - 0.4. In this way, the paste consumption can be saved by 7% - 15%.

[0145] In one embodiment, L8 is between 0.8 mm and 1.2 mm.

[0146] In one embodiment, the second connection pad 151 further includes a second connection layer 1512 formed on the second sub-connection pad 1511. The second connection layer 1512 is located on the side of the second sub-connection pad 1511 facing away from the first gate line 12. By providing the second connection layer 1512, the connection tightness and connection stability between the second sub-connection pad 1511 and the second solder tape 30 can be enhanced.

[0147] It can be understood that in the same second connection pad 151, the number of the second connection layers 1512 and the number of the second sub-connection pads 1511 can be the same. Specifically, one second connection layer 1512 is provided on each second sub-connection pad 1511.

[0148] In one embodiment, the second connection layer 1512 includes a conductive adhesive or a metal plating. When the second connection layer 1512 is a conductive adhesive, the second connection layer 1512 can bond the second solder strip 30 to the second sub-connection pad 1511, which is beneficial to improving the connection stability. When the second connection layer 1512 is a metal plating, the second connection layer 1512 can be connected to the second solder strip 30 by welding. In one example, the metal plating can be a tin plating.

[0149] In one embodiment, the positive projection of the portion of the second gate line 14 located between two adjacent second sub-connection pads 1511 on the cell body 11 is the second positive projection. The second connection pad 151 further includes a second protective layer 1513 formed on the second gate line 14, and the positive projection of the second protective layer 1513 on the cell body 11 covers at least a part of the second positive projection. By providing the second protective layer 1513, the second gate line 14 between the two second sub-connection pads 1511 can be protected, preventing the second gate line 14 from being melted by the second solder strip 30 during the welding process, thereby affecting the efficiency of the solar cell 10.

[0150] In one embodiment, the material of the second protective layer 1513 is an insulating material. The insulating material can be epoxy resin, phenolic resin, silicone rubber, polyimide, polyvinyl butyral ester, etc. The specific type of the insulating material is not particularly limited in the embodiments of the present application.

[0151] In one embodiment, as Figure 3 shown, the second connection layer 1512 includes a conductive adhesive, and the outer contour of the positive projection of the second sub-connection pad 1511 on the cell body 11 is located outside the outer contour of the positive projection of the corresponding second connection layer 1512 on the cell body 11. That is: in the plan view, the area of the second connection layer 1512 is smaller than the area of the second sub-connection pad 1511.

[0152] Furthermore, in the same second connection pad 151, the second protective layer 1513 is disposed between the two second connection layers 1512 corresponding to two adjacent second sub-connection pads 1511 respectively, and the second protective layer 1513 is located on the side of the second sub-connection pad 1511 away from the cell body 11. That is: the two ends of the second protective layer 1513 along the second direction Y are respectively placed on the two second sub-connection pads 1511. In this way, not only can the second protective layer 1513 protect the second gate line 14 between the two second sub-connection pads 1511, but also the coverage area of the second protective layer 1513 can be reduced, avoiding the influence of the second protective layer 1513 on the connection between the second solder strip 30 and the second sub-connection pad 1511.

[0153] It is understandable that the shape of the conductive adhesive can be square, circular, crescent-shaped or other shapes.

[0154] In one embodiment, the distance between the surface of the second protective layer 1513 close to the battery cell body 11 and the surface of the second protective layer 1513 far from the battery cell body 11 is the third distance. The distance between the surface of the second connection layer 1512 close to the battery cell body 11 and the surface of the second connection layer 1512 far from the battery cell body 11 is the fourth distance. Here, the third distance is the thickness of the second protective layer 1513, and the fourth distance is the thickness of the second connection layer 1512.

[0155] Specifically, the third distance is less than the fourth distance. In this way, it is equivalent to making the thickness of the second protective layer 1513 less than the thickness of the second connection layer 1512. In this way, it can prevent the second protective layer 1513 from raising the second solder strip 30, thereby affecting the close contact between the second solder strip 30 and the second connection layer 1512.

[0156] In one embodiment, as Figure 2 shown, the orthographic projection of the second sub-connection pad 1511 connected to the second protective layer 1513 on the battery cell body 11 and the orthographic projection of the second protective layer 1513 on the battery cell body 11 have an overlapping area; the dimension of the overlapping area along the extension direction of the second grid line 14 is L9. Here, L9 can be understood as the overlapping length of the second protective layer 1513 and the second sub-connection pad 1511.

[0157] Among them, L9 satisfies the following relationship: 0mm < L9 ≤ 0.2mm. Exemplarily, L9 can be 0.01mm, 0.05mm, 0.1mm, 0.15mm, 0.2mm or between any two of the above values. In this way, not only can the second protective layer 1513 protect the second grid line 14 between the two second sub-connection pads 1511, but also the coverage area of the second protective layer 1513 can be reduced, avoiding the influence of the second protective layer 1513 on the connection between the second solder strip 30 and the second sub-connection pad 1511.

[0158] In one embodiment, the dimension of the second grid line 14 along the first direction X is W2, and L9 and W2 satisfy the following relationship: 3W2 ≤ L9 ≤ 5W2. Exemplarily, L9 can be 3 times W1, 4 times W1, 4.5 times W1, 5 times W1, etc. In this way, not only can the second protective layer 1513 protect the second grid line 14 between the two second sub-connection pads 1511, but also the coverage area of the second protective layer 1513 can be reduced, avoiding the influence of the second protective layer 1513 on the connection between the second solder strip 30 and the second sub-connection pad 1511.

[0159] In one embodiment, W2 is between 25μm - 35μm.

[0160] Schematic diagram of the connection between the first solder tape 20 and the first connection pad group 13, and the connection between the second solder tape 30 and the second connection pad group 15 is as shown in Figure 4 、 Figure 5 and Figure 6 shown. Taking the second solder tape 30 and the second grid line 14 as an example, please refer to Figure 5 , the second grid line 14, the second sub-connection pad 1511, the second connection layer 1512 and the second solder tape 30 are connected in a stacked manner in sequence. Please refer to Figure 6 , the second protective layer 1513 insulates the second solder tape 30 from the second grid line 14. At the same time, in order to improve the stability of the second solder tape 30, a filling adhesive 40 is provided between the second protective layer 1513 and the second grid line 14 to fill the gap between the second protective layer 1513 and the second grid line 14.

[0161] In one embodiment, referring to Figure 7 and Figure 8 shown, the second connection layer 1512 is a metal coating, and the metal coating covers the surface of the second sub-connection pad 1511 away from the battery cell body 11. In one example, the metal coating covers the entire upper surface of the second sub-connection pad 1511.

[0162] Furthermore, the second protective layer 1513 is provided between two adjacent second sub-connection pads 1511, and the second protective layer 1513 is in contact with the second grid line 14. In this way, the second protective layer 1513 is prevented from being provided on the second sub-connection pad 1511, and the height of the second protective layer 1513 is prevented from being too high, so that the second solder tape 30 is lifted up and it is not easy for the second solder tape 30 to contact the second connection layer 1512.

[0163] In one embodiment, the distance between the surface of the second protective layer 1513 away from the battery cell body 11 and the battery cell body 11 is less than the distance between the surface of the second connection layer 1512 away from the battery cell body 11 and the battery cell body 11. In this way, the second protective layer 1513 can be prevented from lifting up the second solder tape 30, thereby affecting the close contact between the second solder tape 30 and the second connection layer 1512.

[0164] In one embodiment, the second grid line 14 includes n second sub-segments 141 arranged at intervals along its own extending direction, that is: the second grid line 14 is a discontinuous grid line. The solar cell 10 includes m second connection pad groups 15, and m and n satisfy the following relationship: n = m + 1.

[0165] Specifically, a second connection pad group 15 is provided at the critical position of any two adjacent second sub-segments 141; wherein, at least one second sub-connection pad 1511 of the second connection pad group 15 is provided on one second sub-segment 141, and at least one second sub-connection pad 1511 of the second connection pad group 15 is provided on another second sub-segment 141.

[0166] It should be noted that when the second gate line 14 is a discontinuous gate line, the second protective layer 1513 may not be provided. Further, the second solder strip 30 can be directly welded to the second sub-connection pad 1511.

[0167] In one embodiment, as Figure 9 and Figure 10 shown, the first connection pad 131 includes three first sub-connection pads 1311. Among them, the size of the middle first sub-connection pad 1311 along the extension direction of the first gate line 12 (i.e., the second direction Y) is smaller than the sizes of the other first sub-connection pads 1311 along the extension direction of the first gate line 12 (i.e., the second direction Y).

[0168] Here, it is equivalent to making the length of the middle first sub-connection pad 1311 the shortest and the lengths of the first sub-connection pads 1311 on both sides the longest. In this way, the first solder strip 20 and the first connection pad 131 can have more contact points. Even if the first solder strip 20 has poor contact with one first sub-connection pad 1311, it can have good contact with the other two first sub-connection pads 1311. In this way, it helps to improve the connection stability between the first solder strip 20 and the first connection pad 131 and is beneficial to reducing the connection resistance.

[0169] In one embodiment, as Figure 9 and Figure 10 shown, the second connection pad 151 includes three second sub-connection pads 1511. Among them, the size of the middle second sub-connection pad 1511 along the extension direction of the second gate line 14 (i.e., the second direction Y) is smaller than the sizes of the other second sub-connection pads 1511 along the extension direction of the second gate line 14 (i.e., the second direction Y). Here, it is equivalent to making the length of the middle second sub-connection pad 1511 the shortest and the lengths of the second sub-connection pads 1511 on both sides the longest. In this way, the second solder strip 30 and the second connection pad 151 can have more contact points. Even if the second solder strip 30 has poor contact with one second sub-connection pad 1511, it can have good contact with the other two second sub-connection pads 1511. In this way, it helps to improve the connection stability between the second solder strip 30 and the second connection pad 151 and is beneficial to reducing the connection resistance.

[0170] Further, referring to Figure 10As shown, the first connection pad 131 includes three first connection layers 1312 and two first protective layers 1313. The three first connection layers 1312 are respectively disposed on three first sub-connection pads 1311, and the two first protective layers 1313 are respectively disposed between two adjacent first connection layers 1312. The second connection pad 151 includes three second connection layers 1512 and two second protective layers 1513. The three second connection layers 1512 are respectively disposed on three second sub-connection pads 1511, and the two second protective layers 1513 are respectively disposed between two adjacent second connection layers 1512.

[0171] In one embodiment, the first insulating layer 161, the second insulating layer 171, the first protective layer 1313, and the second protective layer 1513 are made of the same material. The materials of the first insulating layer 161, the second insulating layer 171, the first protective layer 1313, and the second protective layer 1513 can be epoxy resin, phenolic resin, silicone rubber, polyimide, polyvinyl butyral, etc. Thus, it is beneficial to reduce the manufacturing cost.

[0172] In one embodiment, the thickness of the first connection layer 1312 and the second connection layer 1512 can be between 50μm and 100μm. Specifically, it can be 50μm, 60μm, 70μm, 80μm, 90μm, 100μm, etc. By making the thickness of the first connection layer 1312 and the second connection layer 1512 within the above range, the connection effect of the solder tape can be ensured.

[0173] In one embodiment, the distance between the surface of the first protective layer 1313 away from the battery cell body 11 and the battery cell body 11 < 30um, and the distance between the surface of the second protective layer 1513 away from the battery cell body 11 and the battery cell body 11 < 30um. Thus, after the grid line is welded, it is beneficial to reduce the warping and surface contamination of the solar cell 10.

[0174] In one embodiment, referring to Figure 2 As shown, the dimension of the first protective layer 1313 along the second direction Y is the length of the first protective layer 1313, and the length at the center of the first protective layer 1313 is less than the lengths at both ends of the first protective layer 1313 along the first direction X. That is: the center of the first protective layer 1313 is short, and the two ends are long. The dimension of the second protective layer 1513 along the second direction Y is the length of the second protective layer 1513, and the length at the center of the second protective layer 1513 is less than the lengths at both ends of the second protective layer 1513 along the first direction X. That is: the center of the second protective layer 1513 is short, and the two ends are long. The above settings are beneficial to the interconnection of the solder tape and the sub-connection pad.

[0175] It can be understood that the shapes of the first protective layer 1313 and the second protective layer 1513 can be strip-shaped, diamond-shaped, oval-shaped, etc., or other shapes.

[0176] In one embodiment, as Figure 13 shown, a plurality of second grid lines 14 are provided on a side of the cell body 11 away from the first grid line 12. That is, one of the first grid line 12 and the second grid line 14 is provided on the light-receiving surface of the cell body 11, and the other is provided on the backlight surface of the cell body 11.

[0177] It should be noted that when connecting the first solder ribbon 20 and the second solder ribbon 30, a high-precision camera can be used to position the first connection pad group 13 and the second connection pad group 15, and then the first solder ribbon 20 is placed above the first connection layer 1312 to make the first solder ribbon 20 fully contact with the first connection layer 1312, and the second solder ribbon 30 is placed above the second connection layer 1512 to make the second solder ribbon 30 fully contact with the second connection layer 1512, so as to realize the interconnection of the solder ribbon and the solar cell 10.

[0178] When performing efficiency testing on the solar cell 10 provided in the embodiment of the present application, a non-contact testing method or a contact testing method can be used. When using the contact testing method, the probes of the existing testing instruments can be adjusted adaptively so that the probes can fully contact the electrodes of the battery (such as the first sub-connection pad 1311 or the second sub-connection pad 1511).

[0179] In a second aspect, referring to Figure 4 shown, the embodiment of the present application provides a photovoltaic module, including a first solder ribbon 20 and the solar cell 10 in any of the above embodiments. The first solder ribbon 20 is connected to the first sub-connection pad 1311 of the first connection pad group 13.

[0180] In one embodiment, the photovoltaic module further includes a second solder ribbon 30, and the second solder ribbon 30 is connected to the second sub-connection pad 1511 of the second connection pad group 15 of the solar cell 10.

[0181] It can be understood that the cross-sectional shapes of the first solder ribbon 20 and the second solder ribbon 30 can be rectangular, triangular, pentagonal, hexagonal, octagonal, etc. Here, the listed polygons are all convex polygons. The embodiment of the present application does not make special limitations on the cross-sectional shapes of the first solder ribbon 20 and the second solder ribbon 30. In a preferred embodiment, the cross-sectional shapes of the first solder ribbon 20 and the second solder ribbon 30 are triangular, rectangular, or a polygon formed by a combination of triangle and rectangle.

[0182] Taking the example that the first connection pad 131 includes two first sub-connection pads 1311 and the second connection pad 151 includes two second sub-connection pads 1511, a first connection layer 1312 is respectively provided on each of the two first sub-connection pads 1311, and a second connection layer 1512 is respectively provided on each of the two second sub-connection pads 1511.

[0183] The width of the first solder tape 20 is a, the minimum distance between the two first connection layers 1312 is b, and the distance between the centers of the two first connection layers 1312 is c, where b < a + 0.1 mm and c < a + 0.2 mm. The width of the second solder tape 30 is d, the minimum distance between the two second connection layers 1512 is e, and the distance between the centers of the two second connection layers 1512 is f, where e < d + 0.1 mm and f < d + 0.2 mm.

[0184] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0185] The above-described embodiments only express several implementation manners of the present application. The description is relatively specific and detailed, but it cannot be understood as a limitation on the scope of the patent application. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present application, several modifications and improvements can still be made, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application shall be subject to the appended claims.

Claims

1. A solar cell, characterized in that: include: Battery cell body; A plurality of first grid lines are arranged on one side of the battery cell body, and the plurality of first grid lines are arranged at intervals along a first direction; At least one first connection pad group, the first connection pad group comprising a plurality of first connection pads corresponding to the plurality of first gate lines one by one; each of the first connection pads is disposed on a corresponding one of the first gate lines; Wherein, at least part of the first connection pads include at least two first sub-connection pads arranged at intervals along the extending direction of the first gate line.

2. The solar cell according to claim 1, characterized in that The first connection pad further includes a first connection layer formed on the first sub-connection pad; The first connection layer is located on a side of the first sub-connection pad away from the first gate line.

3. The solar cell according to claim 2, characterized in that: The first connection layer includes conductive glue or a metal plating layer.

4. The solar cell according to claim 2, characterized in that: The orthographic projection of the portion of the first gate line between two adjacent first sub-connection pads on the battery cell body is a first orthographic projection; The first connection pad further includes a first protection layer formed on the first gate line, and the orthographic projection of the first protection layer on the battery cell body covers at least a portion of the first orthographic projection.

5. The solar cell according to claim 4, characterized in that: The first connection layer includes a conductive adhesive, and the orthographic projection outer contour of the first sub-connection pad on the battery cell body is located at the periphery of the orthographic projection outer contour of the corresponding first connection layer on the battery cell body; In the same first connection pad, the first protection layer is disposed between two first connection layers respectively corresponding to two adjacent first sub-connection pads, and the first protection layer is located on a side of the first sub-connection pad away from the battery cell body.

6. The solar cell according to claim 5, characterized in that The distance between the surface of the first protective layer close to the battery cell body and the surface of the first protective layer away from the battery cell body is a first distance; The distance between the surface of the first connection layer close to the battery cell body and the surface of the first connection layer away from the battery cell body is a second distance; The first distance is smaller than the second distance.

7. The solar cell according to claim 5, characterized in that: The orthographic projection of the first sub-connection pad connected to the first protection layer on the battery cell body and the orthographic projection of the first protection layer on the battery cell body have an overlapping area; the size of the overlapping area along the extension direction of the first gate line is L1; Wherein, L1 satisfies the following relationship: 0mm<L1≤0.2mm; and / or, the dimension of the first gate line along the first direction is W1, and L1 and W1 satisfy the following relationship: 3W1≤L1≤5W1.

8. The solar cell according to claim 4, characterized in that: The first connection layer includes a metal plating layer, and the metal plating layer covers a surface of a side of the first sub-connection pad away from the battery cell body; The first protection layer is disposed between two adjacent first sub-connection pads, and the first protection layer is in contact with the first gate line.

9. The solar cell according to claim 8, characterized in that A distance between a side surface of the first protection layer away from the battery cell body and the battery cell body is smaller than a distance between a side surface of the first connection layer away from the battery cell body and the battery cell body.

10. The solar cell according to claim 1, characterized in that: The first connection pad includes three first sub-connection pads; Wherein, a size of the first sub-connection pad located in the middle along the extending direction of the first gate line is smaller than sizes of the remaining first sub-connection pads along the extending direction of the first gate line.

11. The solar cell according to claim 1, characterized in that: The first grid line includes n first sub-segments arranged at intervals along its own extension direction, and the solar cell includes m first connection pad groups, where m and n satisfy the following relationship: n=m+1; A first connection pad group is provided at the boundary of any two adjacent first sub-segments; wherein, at least one first sub-connection pad of the first connection pad group is provided on one first sub-segment, and at least one first sub-connection pad of the first connection pad group is provided on another first sub-segment.

12. The solar cell according to any one of claims 1 to 11, characterized in that: The solar cell further comprises: A plurality of second grid lines are provided on the battery cell body, and the plurality of second grid lines are arranged at intervals along the first direction; At least one second connection pad group, including a plurality of second connection pads corresponding to the plurality of second gate lines one by one; each of the second connection pads is disposed on a corresponding second gate line; Wherein, at least part of the second connection pads includes at least two second sub-connection pads arranged at intervals along the extending direction of the second gate line.

13. The solar cell according to claim 12, characterized in that: The plurality of second grid lines are arranged on a side of the battery cell body close to the first grid line; The first gate lines and the second gate lines are alternately arranged along the first direction, and the first connection pad groups and the second connection pad groups are alternately arranged along the second direction; The second direction is parallel to an extending direction of the first gate line and / or the second gate line.

14. The solar cell according to claim 13, characterized in that: The solar cell further comprises: At least one first insulating layer group, the first insulating layer group comprising a plurality of first insulating layers corresponding one by one to the plurality of first gate lines; each of the first insulating layers is disposed on a corresponding one of the first gate lines; At least one second insulating layer group, the second insulating layer group comprising a plurality of second insulating layers corresponding one by one to the plurality of second gate lines; each second insulating layer is disposed on a corresponding second gate line; Wherein, the first insulating layer group corresponds to the second connecting pad group one by one, and in the corresponding first insulating layer group and second connecting pad group, the first insulating layer and the second connecting pad are alternately arranged along the first direction; The second insulating layer groups correspond to the first connecting pad groups one by one. In the corresponding second insulating layer groups and first connecting pad groups, the second insulating layers and the first connecting pads are alternately arranged along the first direction.

15. The solar cell according to claim 13, characterized in that: In the same first connection pad group, the distance between two adjacent first connection pads is L2; ​​the dimension of the first gate line along the first direction is W1, and L2 and W1 satisfy the following relationship: 3W1≤L2≤18W1; And / or, the size of the first connection pad along the extension direction of the first gate line is L3, the size of the second connection pad along the extension direction of the second gate line is L4, and the size of the first gate line along the first direction is W1; L3 and W1 satisfy the following relationship: 20W1≤L3≤40W1; L4 and W1 satisfy the following relationship: 20W1≤L4≤40W1; And / or, the size of the first sub-connection pad along the first direction is L5, the size of the second sub-connection pad along the first direction is L6, and the spacing between adjacent first gate lines and second gate lines is L7; L5 and L7 satisfy the following relationship: 0.1L7≤L5≤0.5L7; L6 and L7 satisfy the following relationship: 0.1L7≤L6≤0.5L7; And / or, in the same second connection pad group, the distance between two adjacent second connection pads is L8; the size of the second gate line along the first direction is W2, and L8 and W2 satisfy the following relationship: 3W2≤L8≤18W2.

16. The solar cell according to claim 12, characterized in that: The second connection pad further includes a second connection layer formed on the second sub-connection pad; The second connection layer is located on a side of the second sub-connection pad away from the first gate line.

17. The solar cell according to claim 16, characterized in that: The second connection layer includes conductive glue or a metal plating layer.

18. The solar cell according to claim 16, characterized in that: The orthographic projection of a portion of the second gate line between two adjacent second sub-connection pads on the battery cell body is a second orthographic projection; The second connection pad further includes a second protection layer formed on the second gate line, and the orthographic projection of the second protection layer on the battery cell body covers at least a portion of the second orthographic projection.

19. The solar cell according to claim 18, characterized in that The second connection layer includes a conductive adhesive, and the orthographic projection outer contour of the second sub-connection pad on the battery cell body is located at the periphery of the orthographic projection outer contour of the corresponding second connection layer on the battery cell body; In the same second connection pad, the second protection layer is disposed between two second connection layers respectively corresponding to two adjacent second sub-connection pads, and the second protection layer is located on a side of the second sub-connection pad away from the battery cell body.

20. The solar cell according to claim 19, characterized in that The distance between the surface of the second protective layer close to the battery cell body and the surface of the second protective layer away from the battery cell body is a third distance; The distance between the surface of the second connection layer close to the battery cell body and the surface of the second connection layer away from the battery cell body is a fourth distance; The third distance is smaller than the fourth distance.

21. The solar cell according to claim 19, characterized in that The orthographic projection of the second sub-connection pad connected to the second protection layer on the battery cell body and the orthographic projection of the second protection layer on the battery cell body have an overlapping area; the size of the overlapping area along the extension direction of the second gate line is L9; Wherein, L9 satisfies the following relationship: 0mm<L9≤0.2mm; and / or, the dimension of the second gate line along the first direction is W2, and L9 and W2 satisfy the following relationship: 3W2≤L9≤5W2.

22. The solar cell according to claim 18, characterized in that The second connection layer is a metal plating layer, and the metal plating layer covers a surface of a side of the second sub-connection pad away from the battery cell body; The second protection layer is disposed between two adjacent second sub-connection pads, and the second protection layer is in contact with the second gate line.

23. The solar cell according to claim 22, characterized in that A distance between a side surface of the second protection layer away from the battery cell body and the battery cell body is smaller than a distance between a side surface of the second connection layer away from the battery cell body and the battery cell body.

24. The solar cell according to claim 12, characterized in that: The second connection pad includes three second sub-connection pads; The size of the second sub-connection pad located in the middle along the extension direction of the second gate line is smaller than the sizes of the other second sub-connection pads along the extension direction of the second gate line.

25. The solar cell according to claim 12, characterized in that The second grid line includes n second sub-segments arranged at intervals along its own extension direction, and the solar cell includes m second connection pad groups, where m and n satisfy the following relationship: n=m+1; A second connection pad group is provided at the boundary of any two adjacent second sub-segments; wherein, at least one second sub-connection pad of the second connection pad group is provided on one second sub-segment, and at least one second sub-connection pad of the second connection pad group is provided on another second sub-segment.

26. The solar cell according to claim 12, characterized in that: The plurality of second gate lines are arranged on a side of the battery cell body away from the first gate lines.

27. A photovoltaic module, characterized in that: include: The solar cell according to any one of claims 1 to 26; A first welding strip is connected to the first sub-connection pad of the first connection pad group.

28. The photovoltaic module according to claim 27, characterized in that: The photovoltaic assembly further includes a second welding ribbon connected to the second sub-connection pad of the second connection pad group of the solar cell.

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