Solar cell grid and photovoltaic module

Abstract

This application relates to a solar cell mesh and a photovoltaic module. The solar cell mesh includes a solar cell body, multiple first sub-grids, a second sub-grid, and multiple pads. The first sub-grids extend along a first direction, and the multiple first sub-grids are spaced apart on the solar cell body along a second direction. The second sub-grids are located at at least one end of the first sub-grids along the first direction and are electrically connected to the multiple first sub-grids. The multiple pads are spaced apart on the second sub-grids along the second direction. The first and second directions intersect each other and are all perpendicular to the thickness direction of the solar cell body. This application reduces the risk of microcracks occurring inside the solar cell body and helps to improve the photoelectric conversion efficiency of the solar cell body.

Description

Technical Field

[0001] This application relates to the field of photovoltaic technology, and in particular to a solar cell grid and a photovoltaic module. Background Technology

[0002] In the manufacturing process of photovoltaic modules, the design of the metal wire structure on the solar cell that collects and transmits current plays a crucial role in the manufacturing and performance of the solar cell.

[0003] In related technologies, the structure of the metal wires on the solar cells of photovoltaic modules can easily lead to greater stress inside the cells, increasing the risk of microcracks and resulting in lower conversion efficiency. Summary of the Invention

[0004] Therefore, it is necessary to provide a cell grid and a photovoltaic module to address the problems that the structure of the metal wires on the cells of photovoltaic modules in related technologies can easily lead to large stress inside the cells, a high risk of microcracks inside the cells, and low conversion efficiency of the cells.

[0005] According to one aspect of this application, a solar cell mesh is provided, the solar cell mesh comprising:

[0006] The battery cell itself;

[0007] Multiple first sub-grids extend along a first direction, and the multiple first sub-grids are spaced apart along a second direction on the battery cell body;

[0008] A second sub-gate, wherein the second sub-gate is disposed at at least one end of the first sub-gate along the first direction, and the second sub-gate is electrically connected to a plurality of the first sub-gates respectively; and

[0009] Multiple pads, the multiple pads being spaced apart on the second sub-gate along the second direction;

[0010] The first direction and the second direction intersect each other and are both perpendicular to the thickness direction of the battery cell body.

[0011] In one embodiment, the battery cell body includes a light-incident surface and a back-light surface disposed opposite to each other along its thickness direction; the plurality of first sub-gates include a plurality of first positive sub-gates and a plurality of first negative sub-gates, the first positive sub-gates and the first negative sub-gates being alternately disposed on the back-light surface of the battery cell body along the second direction.

[0012] In one embodiment, the battery cell body includes a light-incident surface and a back-light surface disposed opposite to each other along its thickness direction; the plurality of first sub-gates include a plurality of first positive sub-gates and a plurality of first negative sub-gates, the plurality of first positive sub-gates and the plurality of first negative sub-gates being disposed at intervals along the second direction on the back-light surface.

[0013] In one embodiment, the second sub-gate includes a second positive sub-gate and a second negative sub-gate, the second positive sub-gate being electrically connected to one end of a plurality of first positive sub-gates along the first direction; the second negative sub-gate being electrically connected to one end of a plurality of first negative sub-gates along the first direction.

[0014] In one embodiment, the battery cell screen further includes a first connecting gate and a second connecting gate;

[0015] The cell grid includes at least two second positive electrode sub-gates and at least two second negative electrode sub-gates disposed at the same end of the cell body along the first direction; the at least two second positive electrode sub-gates are electrically connected through the first connecting gate; the at least two second negative electrode sub-gates are electrically connected through the second connecting gate.

[0016] According to another aspect of this application, a photovoltaic module is provided, comprising:

[0017] The aforementioned battery cell mesh; and

[0018] An electrical connector, at least a portion of which is disposed between two adjacent solar cell screens;

[0019] In this configuration, the second sub-gate of one of two adjacent cell screens is electrically connected to the electrical connector via a plurality of pads provided on its second sub-gate, and the second sub-gate of the other of the two adjacent cell screens is electrically connected to the electrical connector via a plurality of pads provided on its second sub-gate, thereby achieving electrical connection between the two adjacent cell screens.

[0020] In one embodiment, in each of the battery cell grids, the plurality of second sub-grids include a second positive sub-grid and a second negative sub-grid;

[0021] The second positive sub-gate of one of the battery cell screens is electrically connected to the electrical connector through a plurality of pads provided on its second positive sub-gate, and the second negative sub-gate of the other of two adjacent battery cell screens is electrically connected to the electrical connector through a plurality of pads provided on its second negative sub-gate, so as to realize the electrical connection between the two adjacent battery cell screens.

[0022] In one embodiment, the electrical connector includes a plurality of sub-connectors 320 spaced apart along the second direction;

[0023] The second positive sub-gate of one of the battery cell screens is electrically connected to one of the sub-connectors through a plurality of pads provided on its second positive sub-gate, and the second negative sub-gate of the other of the two adjacent battery cell screens is electrically connected to the sub-connector through a plurality of pads provided on its second negative sub-gate, so as to realize the electrical connection between the two adjacent battery cell screens.

[0024] In one embodiment, the electrical connector is a tin-coated solder strip or copper foil.

[0025] In one embodiment, the electrical connector is a copper foil, and the electrical connector has a plurality of hollow holes, which are spaced apart along the second direction on the electrical connector.

[0026] The aforementioned solar cell grid is electrically connected to multiple first sub-grids by having a second sub-grid disposed at at least one end of the first sub-grid along the first direction. This allows for electrical connection between the solar cell body and external electrodes through the second sub-grid, eliminating the need for a main grid solder strip. This reduces the risk of internal stress and microcracks caused by a main grid on the solar cell body. Furthermore, the absence of a main grid reduces the area of ​​the solar cell body obstructed by the main grid, thereby increasing the contact area between the solar cell body and sunlight and improving the photoelectric conversion efficiency of the solar cell body. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of a photovoltaic module according to this application.

[0028] Figure 2 for Figure 1 A magnified view of a portion of the photovoltaic module shown.

[0029] Figure 3 for Figure 1 The photovoltaic module shown is a side view.

[0030] Figure 4 This is a schematic diagram showing the structure in which the first and second sub-grids are alternately arranged on the same side of the battery cell body.

[0031] Figure 5 This is a schematic diagram showing a structure in which multiple first sub-grids and multiple second sub-grids are sequentially arranged on the same side of the solar cell body.

[0032] Figure 6a This is a front view of the integral electrical connector.

[0033] Figure 6b This is a front view of a hollowed-out electrical connector.

[0034] Figure 6c This is a front view of a segmented electrical connector.

[0035] Figure 7a A side view of a first embodiment of the bent shape of an electrical connector.

[0036] Figure 7b A side view of a second embodiment of the bent shape of the electrical connector.

[0037] Figure 7c A side view of a third embodiment of the bent shape of an electrical connector.

[0038] Figure 7d A side view of a fourth embodiment of the bent shape of an electrical connector.

[0039] Figure 8 A schematic diagram of a structure with conductive components installed on the battery cell body.

[0040] Explanation of reference numerals in the attached figures:

[0041] 10. Photovoltaic modules;

[0042] 11. Battery cell mesh printing plate;

[0043] 100, First sub-gate; 110, First positive sub-gate; 120, First negative sub-gate; 130, First connection gate; 140, First pad;

[0044] 200, Second sub-gate; 210, Second positive sub-gate; 220, Second negative sub-gate; 230, Second connecting gate; 240, Second pad;

[0045] 300 Electrical connector; 310 Hole; 320 Sub-electrical connector; 330 Stepped component; 331 First step surface; 332 Second step surface; 333 Connecting surface; 334 Corner; 335 First corner; 336 Second corner; 337 Sub-corner;

[0046] 400. Connector; 410. First sub-conductor section; 420. Second sub-conductor section;

[0047] F1, first direction; F2, second direction. Detailed Implementation

[0048] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application are described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of this application. However, this application can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this application. Therefore, this application is not limited to the specific embodiments disclosed below.

[0049] In the description of this application, it should be understood that if terms such as "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0050] Furthermore, where the terms "first" and "second" appear, these terms are for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0051] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "joining," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0052] In this application, unless otherwise expressly specified and limited, the use of descriptions such as "above" or "below" the second feature indicates that the first and second features are in direct contact or indirect contact via an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. Similarly, "below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0053] It should be noted that if an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. If an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. If so, the terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used in this application are for illustrative purposes only and do not represent the only possible implementation.

[0054] In related technologies, the extension directions of the positive and negative sub-grids of photovoltaic modules are perpendicular to the direction from one cell to another. Therefore, it is usually necessary to use a main grid solder strip to achieve the electrical connection between two adjacent cells. That is, a part of the solder strip is connected to the positive sub-grid of one of the two adjacent cells, and the other part of the solder strip is connected to the negative sub-grid of the other of the two adjacent cells to achieve the electrical connection between the two adjacent cells.

[0055] During the welding process between the busbar solder strip and the solar cell, the solder strip shrinks when heated, easily transmitting the pressure of the shrinkage to the solar cell, causing warping and generating significant internal stress, thus increasing the risk of microcracks within the cell. Furthermore, in existing technologies, the busbar solder strip is typically a circular wire with a circular cross-section, making stress concentration at the edges of the busbar solder strip and the solar cell more likely, further increasing the risk of microcracks at the cell edges.

[0056] Furthermore, the welding of the main grid strip in related technologies often obstructs the solar cells, increasing the light-receiving area on the front of the solar cells, reducing the area of ​​the solar cells that receive light, and thus reducing the conversion efficiency of the solar cells.

[0057] Based on the above problems, please provide a solar cell grid and photovoltaic module that can reduce the risk of microcracks in the solar cell grid and improve the conversion efficiency of the solar cell grid.

[0058] See Figure 1 and Figure 2 As shown, Figure 1This is a schematic diagram of the structure of a photovoltaic module 10 according to this application. Figure 2 for Figure 1 A partially enlarged view of the photovoltaic module 10 shown.

[0059] The solar cell grid 11 provided in this application includes a solar cell body, multiple first sub-gates 100, a second sub-gate 200, and multiple pads. The first sub-gates 100 extend along a first direction F1, and the multiple first sub-gates 100 are spaced apart on the solar cell body along a second direction F2. The first sub-gates 100 are used to collect charge carriers generated by photoexcitation on the solar cell body.

[0060] The first direction F1 and the second direction F2 intersect each other and are both perpendicular to the thickness direction of the solar cell body. For example... Figure 1 In this application, the first direction F1 is parallel to the direction in which one of the two adjacent cell grids 11 in the photovoltaic module 10 points to the other. In other words, the first direction F1 is a transverse arrangement on opposite sides of the cell body along the thickness direction.

[0061] It is understandable that the lateral extension of the first sub-gate 100, compared with the arrangement of the sub-gate vertically and the main gate solder strip horizontally to collect the carriers on the multiple sub-gates in the related technology, eliminates the need for the horizontal main gate solder strip in this application. This is beneficial to reduce the area of ​​the light-incident surface on the solar cell body that is blocked, increase the area of ​​the solar cell body that receives light, and improve the conversion efficiency of the solar cell body.

[0062] The second sub-gate 200 is disposed at at least one end of the first sub-gate 100 along the first direction F1, and the second sub-gate 200 is electrically connected to multiple first sub-gates 100 respectively. The second sub-gate 200 is used to collect the charge carriers of multiple first sub-gates 100 and to guide the collected charge carriers to an external circuit. Compared with the prior art design where the main grid solder ribbon blocks the area of ​​the solar cell body that receives light, the second sub-gate 200 of this application is disposed at the end of the first sub-gate 100 along the first direction F1, and the area of ​​the solar cell body that blocks the light is smaller or even close to zero, which is beneficial to increasing the area of ​​the solar cell body that receives light and improving the conversion efficiency of the solar cell body.

[0063] Multiple pads are spaced along the second direction F2 on the second sub-gate 200, which facilitates the electrical conduction between the second sub-gate 200 and the external circuit through multiple pads. That is, the first sub-gate 100 collects the charge carriers generated by the solar cell body when excited by light, and the second sub-gate 200 collects the charge carriers in the first sub-gate 100. The pads on the second sub-gate 200 are used to electrically connect the second sub-gate 200 and the external circuit, so as to realize the output of the charge carriers generated by the solar cell body when excited by light.

[0064] The solar cell grid 11 provided in this application has a second sub-grid 200 disposed at at least one end of the first sub-grid 100 along the first direction F1 and electrically connected to multiple first sub-grids 100. The second sub-grid 200 can realize the electrical connection between the solar cell body and the external electrode of this application without the need to set the main grid solder strip. This reduces the risk that setting the main grid on the solar cell body will easily cause large internal stress in the solar cell body, leading to microcracks inside the solar cell body. In addition, the absence of the main grid reduces the area of ​​the solar cell body blocked by the main grid, thereby increasing the contact area between the solar cell body and sunlight, which is conducive to improving the photoelectric conversion efficiency of the solar cell body.

[0065] In some embodiments, in conjunction with reference Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, Figure 3 for Figure 1 The side view of the photovoltaic module 10 shown is shown. Figure 4 This is a schematic diagram showing the structure in which the first sub-grid 100 and the second sub-grid 200 are alternately arranged on the same side of the battery cell body. Figure 5 This is a schematic diagram showing a structure in which multiple first sub-grids 100 and multiple second sub-grids 200 are sequentially arranged on the same side of the solar cell body.

[0066] The solar cell body includes a light-incident surface and a back-light surface arranged opposite each other along its thickness direction. Multiple first sub-grids 100 include multiple first positive sub-grids 110 and multiple first negative sub-grids 120. The multiple first positive sub-grids 110 are spaced apart along a second direction F2 on either the light-incident surface or the back-light surface, and the multiple first negative sub-grids 120 are spaced apart along the second direction F2 on the back-light surface. It can be understood that the first positive sub-grids 110 are configured to be located on either the light-incident surface or the back-light surface, and the first negative sub-grids 120 are preferably located on the back-light surface. Thus, depending on requirements, the first positive sub-grids 110 and the first negative sub-grids 120 can be located on both sides of the solar cell body, or the first positive sub-grids 110 can be located on the light-incident surface, and the first negative sub-grids 120 on the back-light surface. This facilitates the placement of the first positive sub-grids 110 on different sides of the solar cell body as needed, resulting in a more adaptable solar cell screen 11.

[0067] In some embodiments, in conjunction with reference Figure 1 , Figure 3 , Figure 4 and Figure 5As shown, the second sub-gate 200 includes a second positive sub-gate 210 and a second negative sub-gate 220. The second positive sub-gate 210 is electrically connected to one end of a plurality of first positive sub-gates 110 along a first direction F1 to collect and converge the charge carriers collected by the plurality of first positive sub-gates 110. The second negative sub-gate 220 is electrically connected to one end of a plurality of first negative sub-gates 120 along the first direction F1 to collect and converge the charge carriers collected by the plurality of first negative sub-gates 120.

[0068] The second positive sub-gate 210 and the second negative sub-gate 220 can realize the electrical connection between the cell body and the external electrode, eliminating the need for the main gate solder strip, reducing the risk of microcracks in the cell body, and improving the photoelectric conversion efficiency of the cell body.

[0069] In some embodiments, in conjunction with reference Figure 1 , Figure 3 , Figure 4 and Figure 5 As shown, the solar cell grid 11 also includes at least two first connecting gates 130 and at least two second connecting gates 230. The solar cell grid 11 includes at least two second positive electrode sub-gates 210 and at least two second negative electrode sub-gates 220 disposed at the same end of the solar cell body along the first direction F1. The at least two second positive electrode sub-gates 210 are electrically connected through the first connecting gates 130, and the at least two second negative electrode sub-gates 220 are electrically connected through the second connecting gates 230. The arrangement of at least two second positive electrode sub-gates 210 and at least two second negative electrode sub-gates 220 is beneficial to improving the collection efficiency of charge carriers. The arrangement of the first connecting gates 130 is beneficial to improving the electrical conduction efficiency between the at least two second positive electrode sub-gates 210, and the arrangement of the second connecting gates 230 is beneficial to improving the electrical conduction efficiency between the at least two second negative electrode sub-gates 220.

[0070] At least two first connecting gates 130 are spaced apart along the second direction F2 to improve the connection strength and electrical conduction efficiency between at least two second positive sub-gates 210. At least two second connecting gates 230 are spaced apart along the second direction F2 to improve the connection strength and electrical conduction efficiency between at least two second negative sub-gates 220.

[0071] The first connecting gate 130 can be configured such that its extension direction intersects with the extension direction of the second positive electrode sub-gate 210, and the second connecting gate 230 can be configured such that its extension direction intersects with the extension direction of the second negative electrode sub-gate 220. That is, it is not limited to the first connecting gate 130 and the second connecting gate 230 extending along the first direction F1. The angle between the first connecting gate 130 and the second positive electrode sub-gate 210 and the angle between the second connecting gate 230 and the second negative electrode sub-gate 220 can be adjusted according to actual needs in order to obtain a more adaptable battery cell grid 11.

[0072] In some embodiments, see Figure 3 , Figure 4 and Figure 5 As shown, the solar cell mesh 11 includes a plurality of first pads 140 and a plurality of second pads 240. The first pads 140 are electrically connected to at least two second positive sub-gates 210, and the second pads 240 are electrically connected to at least two second negative sub-gates 220. Alternatively, the first pads 140 are soldered to at least two second positive sub-gates 210, and the second pads 240 are soldered to at least two second negative sub-gates 220. This improves the connection strength between the at least two second positive sub-gates 210 and the at least two second negative sub-gates 220, thereby improving the electrical conductivity between the at least two second positive sub-gates 210 and the at least two second negative sub-gates 220.

[0073] This application also provides a photovoltaic module 10, which can be referred to in conjunction with the above. Figures 1-5 As shown, the photovoltaic module 10 includes the aforementioned cell grid 11 and electrical connector 300. At least a portion of the electrical connector 300 is disposed between two adjacent cell grids 11 to achieve electrical connection between the two adjacent cell grids 11 by means of the electrical connector 300.

[0074] The second sub-grid 200 of one of two adjacent cell grids 11 is electrically connected to the electrical connector 300 through a plurality of pads provided on its second sub-grid 200, and the second sub-grid 200 of the other of the two adjacent cell grids 11 is electrically connected to the electrical connector 300 through a plurality of pads provided on its second sub-grid 200. The electrical connection between the two adjacent cell grids 11 is achieved by means of the electrical connector 300 and the pads, which is beneficial for providing a stable electrical connection between the two adjacent cell grids 11.

[0075] In some embodiments, the pads can be set as solder joints, or conductive adhesive can be used, or a combination of conductive adhesive and solder joints can be used. The structure of the pads can be set according to specific needs in order to obtain a more suitable photovoltaic module 10.

[0076] In some embodiments, see Figure 3 , Figure 4 and Figure 5As shown, the second positive sub-gate 210 of one of two adjacent cell grids 11 is electrically connected through a plurality of first pads 140 and electrical connectors 300 disposed thereon, and the second negative sub-gate 220 of the other of the two adjacent cell grids 11 is electrically connected through a second pad 240 and electrical connectors 300 disposed thereon. Thus, the electrical connectors 300 are electrically connected to the second positive sub-gate 210 through the first pads 140 and to the second negative sub-gate 220 through the second pads 240, respectively, thereby realizing the electrical connection between the two adjacent cell grids 11 and providing a stable electrical connection between the two adjacent cell grids 11.

[0077] In some embodiments, see Figure 6a , Figure 6b and Figure 6c As shown, Figure 6a This is a front view of the integral electrical connector 300. Figure 6b This is a front view of the hollowed-out electrical connector 300. Figure 6c This is a front view of the segmented electrical connector 300.

[0078] like Figure 6a In the embodiment shown, the electrical connector 300 can be an integral design to improve the connection strength between two adjacent solar cell grids 11. Furthermore, the electrical connector can be tin-coated solder strip or copper foil, which can be selected according to requirements, facilitating the acquisition of a photovoltaic module 10 with higher adaptability.

[0079] like Figure 6b In the embodiment shown, the electrical connector 300 is made of copper foil, and the electrical connector 300 has a plurality of perforated holes 310, which are spaced apart along the second direction F2. The perforated holes 310 help reduce the weight of the electrical connector 300 and facilitate the lightweight design of the photovoltaic module 10.

[0080] like Figure 6a He Ru Figure 6b In the embodiment shown, the contact area between the electrical connector 300 and the battery cell mesh 11 is large, and the compressive pressure between them is small, which reduces the risk of edge microcracks in the battery cell mesh 11.

[0081] like Figure 6cIn the embodiment shown, the electrical connector 300 includes a plurality of sub-connectors 320, which are spaced apart along the second direction F2. The second positive electrode sub-gate 210 of one of two adjacent cell meshes 11 is electrically connected to one of the sub-connectors 320 via a plurality of pads thereon. The second negative electrode sub-gate 220 of the other adjacent cell mesh 11 is electrically connected to the sub-connector 320 via a plurality of pads thereon, thereby achieving electrical connection between the two adjacent cell meshes 11. Alternatively, one sub-connector 320 may be electrically connected to at least two pads to improve the electrical connection strength between the sub-connector 320 and the second positive electrode sub-gate 210.

[0082] Based on the combination of the above embodiments, this application provides the following three embodiments to reduce the risk of microcracks inside the solar cell body and improve the photoelectric conversion efficiency of the solar cell body.

[0083] Example 1

[0084] See Figure 1 , Figure 2 and Figure 3 As shown, in this embodiment, multiple first positive electrode sub-gates 110 are arranged at intervals along the second direction F2 on the light-incident surface, and multiple first negative electrode sub-gates 120 are arranged at intervals along the second direction F2 on the backlight surface. Both the first positive electrode sub-gates 110 and the first negative electrode sub-gates 120 extend along the first direction F1, which helps to reduce the light-blocking area, increase the light-receiving area of ​​the battery cell body, and improve the photoelectric conversion efficiency of the battery cell body.

[0085] In this embodiment, two second positive electrode sub-gates 210 and two second negative electrode sub-gates 220 are provided. The two second positive electrode sub-gates 210 are spaced apart along the first direction F1 on the light-incident surface, and the two second negative electrode sub-gates 220 are spaced apart along the first direction F1 on the back-light surface. The second positive electrode sub-gates 210 and the second negative electrode sub-gates 220 are located at opposite ends of the battery cell body along the first direction F1, so that the electrical connector 300 can be electrically connected to the two battery cell bodies facing each other, thereby facilitating the connection between the electrical connector 300 and the two adjacent battery cell bodies.

[0086] In this embodiment, a plurality of first pads 140 spaced apart along a second direction F2 and a plurality of second pads 240 spaced apart along a second direction F2 are provided. The first pads 140 are electrically connected between two second positive sub-gates 210 and to an electrical connector 300. The second pads 240 are electrically connected between two second negative sub-gates 220 and to an electrical connector 300. By providing the first pads 140 and the second pads 240, the connection strength and electrical conductivity between the two second positive sub-gates 210 and between the two second negative sub-gates 220 are improved.

[0087] In this embodiment, two first connecting gates 130 and two second connecting gates 230 are provided. The two first connecting gates 130 are spaced apart along the second direction F2 and are respectively located at both ends of the second positive sub-gate 210 along the second direction F2. The two second connecting gates 230 are spaced apart along the second direction F2 and are respectively located at both ends of the second negative sub-gate 220 along the second direction F2. The two first connecting gates 130 and the two second connecting gates 230 improve the electrical connection strength between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0088] Furthermore, both the first connecting gate 130 and the second connecting gate 230 extend along the first direction F1, that is, the extension direction of the first connecting gate 130 is perpendicular to the extension direction of the second positive sub-gate 210, and the extension direction of the second connecting gate 230 is perpendicular to the extension direction of the second negative sub-gate 220, so as to improve the electrical conduction efficiency between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0089] One side of the electrical connector 300 faces the light-incident surface of one of the two adjacent battery cell bodies, and the other side faces the backlight surface of the other of the two adjacent battery cell bodies. It is electrically connected to the second positive sub-gate 210 of one of the two adjacent battery cell bodies through the first pad 140, and electrically connected to the second negative sub-gate 220 of the other of the two adjacent battery cell bodies through the second pad 240, thereby realizing the electrical connection between the two adjacent battery cell screens 11.

[0090] In some embodiments, see Figure 7a , Figure 7b , Figure 7c and Figure 7d As shown, the electrical connector 300 can be configured with different bending shapes to connect between two adjacent battery cell bodies in this embodiment.

[0091] The embodiment is shown in Figure 7. Figure 7a A side view of a first embodiment of the bent shape of the electrical connector 300.

[0092] In this embodiment, the electrical connector 300 is configured as a stepped member 330, which is a stepped structure including two corners 334. One end of the stepped member 330 faces and is connected to the second positive electrode sub-gate 210 on the light-incident surface of one of the two adjacent solar cell bodies, and the other end faces and is connected to the second negative electrode sub-gate 220 on one of the two adjacent solar cell bodies. The stepped structure helps to reduce the space occupied between the two adjacent solar cell bodies, making it easier to shorten the distance between the two adjacent solar cell bodies, which is beneficial for the miniaturization design of the photovoltaic module 10.

[0093] Figure 7b A side view of a second embodiment of the bent shape of the electrical connector 300.

[0094] In this embodiment, the electrical connector 300 is configured as a stepped member 330, and the corner 334 of the stepped member 330 is chamfered, which helps to protect the end of the battery cell body facing the electrical connector 300 and reduce the risk of impact damage to the battery cell body.

[0095] Figure 7c A side view of a third embodiment of the bent shape of the electrical connector 300.

[0096] In this embodiment, the electrical connector 300 is configured as a stepped member 330. The stepped member 330 includes a first stepped surface 331, a second stepped surface 332, and a connecting surface 333 connecting the first stepped surface 331 and the second stepped surface 332. The first stepped surface 331 is used to face and connect to the second positive electrode sub-gate 210 on the light-incident surface of one of the two adjacent battery cell bodies. The second stepped surface 332 is used to face and connect to the second negative electrode sub-gate 220 on one of the two adjacent battery cell bodies.

[0097] The stepped structure includes at least two corners 334, two of which include a first corner 335 and a second corner 336. The first corner 335 is defined between the first stepped surface 331 and the connecting surface 333, and the second corner 336 is defined between the second stepped surface 332 and the connecting surface 333. Both the first corner 335 and the second corner 336 are obtuse angles. By setting the angles of the first corner 335 and the second corner 336, the distance between the first stepped surface 331 and the second stepped surface 332 along the first direction F1 can be adjusted, thereby facilitating the adjustment of the distance between two adjacent battery cell bodies along the first direction F1, and enabling the battery cell bodies to have different distances according to different needs.

[0098] Figure 7d A side view of a fourth embodiment of the bent shape of the electrical connector 300.

[0099] In this embodiment, the electrical connector 300 is configured as a stepped member 330. The corner 334 of the stepped member 330 includes at least two sub-corners 337, so that the multiple sub-corners 337 can play a buffering role, thereby reducing the bending degree of the stepped member 330 at the corner 334 and improving the structural strength of the electrical connector 300.

[0100] This is understandable, as shown in the picture. Figure 7b , Figure 7c and Figure 7d The electrical connector 300 in the illustrated embodiment has a relatively low degree of bending and relatively high structural strength.

[0101] Example 2

[0102] See Figure 4 As shown, in this embodiment, the first positive electrode sub-gate 110 and the first negative electrode sub-gate 120 are alternately disposed on the back surface of the battery cell body along the second direction F2, so as to reduce the shading of the light-incident surface of the battery cell body, thereby increasing the light-receiving area of ​​the battery cell body and improving the photoelectric conversion efficiency of the battery cell body.

[0103] In this embodiment, both the first positive electrode sub-gate 110 and the first negative electrode sub-gate 120 extend along the first direction F1. This embodiment also includes two second positive electrode sub-gates 210 and two second negative electrode sub-gates 220. The two second positive electrode sub-gates 210 and the two second negative electrode sub-gates 220 are spaced apart along the first direction F1 on the backlight surface. The second positive electrode sub-gates 210 and the second negative electrode sub-gates 220 are located at opposite ends of the battery cell body along the first direction F1, facilitating the electrical connection of the electrical connector 300 to the two mutually facing ends of the two battery cell bodies, thus improving the ease of connection between the electrical connector 300 and the two adjacent battery cell bodies.

[0104] In this embodiment, a plurality of first pads 140 spaced apart along a second direction F2 and a plurality of second pads 240 spaced apart along a second direction F2 are provided. The first pads 140 are electrically connected between two second positive sub-gates 210 and to an electrical connector 300. The second pads 240 are electrically connected between two second negative sub-gates 220 and to an electrical connector 300. By providing the first pads 140 and the second pads 240, the connection strength and electrical conductivity between the two second positive sub-gates 210 and between the two second negative sub-gates 220 are improved.

[0105] In this embodiment, two first connecting gates 130 and two second connecting gates 230 are provided. The two first connecting gates 130 are spaced apart along the second direction F2 and are respectively located at both ends of the second positive sub-gate 210 along the second direction F2. The two second connecting gates 230 are spaced apart along the second direction F2 and are respectively located at both ends of the second negative sub-gate 220 along the second direction F2. The two first connecting gates 130 and the two second connecting gates 230 improve the electrical connection strength between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0106] In this embodiment, both the first connecting gate 130 and the second connecting gate 230 extend along the first direction F1, that is, the extension direction of the first connecting gate 130 is perpendicular to the extension direction of the second positive sub-gate 210, and the extension direction of the second connecting gate 230 is perpendicular to the extension direction of the second negative sub-gate 220, so as to improve the electrical conduction efficiency between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0107] The electrical connector 300 is located on the backlight side of two adjacent solar cell bodies, preventing it from blocking the light-receiving side of the backlight side of the solar cell body. This helps to increase the light-receiving area of ​​the solar cell body and improve its photoelectric conversion efficiency. The electrical connector 300 is electrically connected to the second positive electrode sub-gate 210 of one of the two adjacent solar cell bodies via the first pad 140, and electrically connected to the second negative electrode sub-gate 220 of the other adjacent solar cell body via the second pad 240, thus realizing the electrical connection between the two adjacent solar cell bodies.

[0108] Example 3

[0109] See Figure 5 As shown, in this embodiment, multiple first positive electrode sub-gates 110 and multiple first negative electrode sub-gates 120 are spaced apart along the second direction F2 on the backlight surface. For ease of understanding, on the backlight surface of the solar cell body, the multiple first positive electrode sub-gates 110 are disposed on one side of the multiple first negative electrode sub-gates 120 along the second direction F2. The fact that both the multiple first positive electrode sub-gates 110 and the multiple first negative electrode sub-gates 120 are disposed on the backlight surface of the solar cell body helps to reduce the obstruction of the light-receiving surface of the solar cell body, thereby increasing the light-receiving area of ​​the solar cell body and improving the photoelectric conversion efficiency of the solar cell body.

[0110] In this embodiment, both the first positive electrode sub-gate 110 and the first negative electrode sub-gate 120 extend along the first direction F1. This embodiment also includes two second positive electrode sub-gates 210 and two second negative electrode sub-gates 220, with the two second positive electrode sub-gates 210 and the two second negative electrode sub-gates 220 spaced apart along the first direction F1 on the backlight surface. The second positive electrode sub-gates 210 and the second negative electrode sub-gates 220 are located at opposite ends of the battery cell body along the first direction F1. In this embodiment, adjacent battery cell screens 11 are arranged in a centrally symmetrical manner. This facilitates the electrical connection of the electrical connector 300 to the two battery cell bodies facing each other, improving the ease of connection between the electrical connector 300 and the two adjacent battery cell bodies.

[0111] In this embodiment, a plurality of first pads 140 spaced apart along a second direction F2 and a plurality of second pads 240 spaced apart along a second direction F2 are provided. The first pads 140 are electrically connected between two second positive sub-gates 210 and to an electrical connector 300. The second pads 240 are electrically connected between two second negative sub-gates 220 and to an electrical connector 300. By providing the first pads 140 and the second pads 240, the connection strength and electrical conductivity between the two second positive sub-gates 210 and between the two second negative sub-gates 220 are improved.

[0112] In this embodiment, two first connecting gates 130 and two second connecting gates 230 are provided. The two first connecting gates 130 are spaced apart along the second direction F2 and are respectively located at both ends of the second positive sub-gate 210 along the second direction F2. The two second connecting gates 230 are spaced apart along the second direction F2 and are respectively located at both ends of the second negative sub-gate 220 along the second direction F2. The two first connecting gates 130 and the two second connecting gates 230 improve the electrical connection strength between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0113] In this embodiment, both the first connecting gate 130 and the second connecting gate 230 extend along the first direction F1, that is, the extension direction of the first connecting gate 130 is perpendicular to the extension direction of the second positive sub-gate 210, and the extension direction of the second connecting gate 230 is perpendicular to the extension direction of the second negative sub-gate 220, so as to improve the electrical conduction efficiency between the two second positive sub-gates 210 and the two second negative sub-gates 220.

[0114] In this embodiment, the electrical connector 300 is disposed on the backlight side of two adjacent solar cell bodies, thus preventing obstruction of the light-receiving side of the backlight side of the solar cell body. This facilitates increasing the light-receiving area of ​​the solar cell body and improving its photoelectric conversion efficiency. The electrical connector 300 is electrically connected to the second positive electrode sub-gate 210 of one of the two adjacent solar cell bodies via the first pad 140, and electrically connected to the second negative electrode sub-gate 220 of the other adjacent solar cell body via the second pad 240, thereby achieving electrical connection between the two adjacent solar cell bodies.

[0115] All three embodiments described above do not require the use of main grid solder strips, reducing the risk of microcracks inside the solar cell and improving the photoelectric conversion efficiency of the solar cell.

[0116] The above embodiments do not limit the structure of the cell screen 11. In other words, the above embodiments can be applied to various cell designs. Existing cells are generally divided into P-type cells and N-type cells. P-type cells are formed by diffusing phosphorus on P-type semiconductor materials, while N-type cells are formed by implanting boron on N-type semiconductor materials. P-type cells have advantages such as relatively simple manufacturing process and low cost, while N-type cells have advantages such as high conversion efficiency, high bifaciality, low temperature coefficient, no light decay, good weak light effect, and longer carrier lifetime. This application can select P-type cells or N-type cells according to different needs, and apply the design of the cell screen 11 of the above-described various embodiments to the selected different types of cells.

[0117] The types of solar cells include, but are not limited to, passivated emitter rear cell (PERC), tunnel oxide passivated contact (TOPCon), intrinsic thin-film heterojunction (HJT), interdigitated back contact (IBC), and perovskite cells.

[0118] 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 localized aluminum back field, a metallic aluminum back electrode, and a back passivation layer (Al2O3 / SiNx). PERC cells use a passivation film to passivate the back side, replacing the all-aluminum back field, enhancing light reflection within the silicon substrate, reducing the recombination rate on the back side, and improving the cell efficiency by 0.5%-1%.

[0119] For TOPCon cells, along their thickness direction, the TOPCon cell sequentially includes 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 the silver electrode. The back of the cell consists of an ultrathin silicon oxide layer (1nm~2nm) and a phosphorus-doped microcrystalline amorphous mixed Si film, which together form a passivation contact structure. This structure can block 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, resulting in 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.

[0120] 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.

[0121] IBC cells, a type of BC (Back Contact solar cell), have no grid lines obstructing the front side, resulting in a more aesthetically pleasing appearance. They offer advantages such as high conversion efficiency, low degradation, and a good temperature coefficient. Along the thickness direction, an IBC cell sequentially includes a silicon nitride anti-reflection layer, an N+ front surface field, an N-type substrate silicon layer, a P+ emitter, an N+ back field, an aluminum oxide passivation layer, a silicon nitride anti-reflection layer, and a silver electrode. IBC cells utilize ion implantation technology to obtain uniform P- and N-regions with precise and controllable junction depth. The absence of grid lines on the front side eliminates light-shielding current loss from the metal electrodes, maximizing the utilization of incident photons and improving short-circuit current by approximately 7% compared to conventional solar cells. Due to the back-contact structure, grid line obstruction is eliminated, allowing for a wider grid line ratio, reducing series resistance and achieving a high fill factor. Optimized design of surface passivation and light-trapping structures allows for lower front surface recombination rates and surface reflections.

[0122] The cell grid design 11 in Embodiment 1 of this application can be applied to TOPCon, PERC, and HJT cells. The cell grid design 11 in Embodiment 1 combines the advantages of TOPCon cells, such as high photoelectric conversion efficiency, low light-induced degradation, good temperature coefficient, and low degradation rate, while further reducing the shading area, thereby increasing the light-receiving area of ​​the cell body and improving the photoelectric conversion efficiency. The cell grid design 11 in Embodiment 1 can also be combined with PERC cells to increase the light-receiving area of ​​the cell body, improve the photoelectric conversion efficiency, enhance the internal back reflection of light on the silicon substrate, reduce the recombination rate on the back side, and further improve the cell efficiency. The cell grid design 11 in Embodiment 1 can also be combined with HJT cells, enabling the cell to have high conversion efficiency, low temperature coefficient, excellent weak light response, and no light degradation, while reducing the shading area and improving the photoelectric conversion efficiency of the cell.

[0123] The designs of the cell screen 11 in Embodiments 2 and 3 of this application can both be applied to BC cells, which facilitates an unobstructed design on the front side of the cell and improves the photoelectric conversion efficiency of the cell. Specifically, the design of the cell screen 11 in Embodiment 2 can be applied to IBC cells within the BC cell, where the sub-grids are formed in an interdigitated shape on the back side of the cell, eliminating the need to consider the issue of grid lines blocking light, thereby improving the photoelectric conversion efficiency of the cell.

[0124] In some embodiments, see Figure 8 As shown, Figure 8 A schematic diagram of a structure with a conductor 400 on the cell body. The conductor 400 can be placed at least at one end of the first sub-grid 100 to replace the second sub-grid 200. That is, the cell screen 11 also includes the conductor 400, which includes a first sub-conductor segment 410 and multiple second sub-conductor segments 420. The multiple second sub-conductor segments 420 are electrically connected to the first sub-conductor segment 410, the first sub-conductor segment 410 is electrically connected to at least one end of the first sub-grid 100, and the multiple second sub-conductor segments 420 are electrically connected to the electrical connector 300 via pads, with each of the multiple second sub-conductor segments 420 correspondingly electrically connected to at least one pad. In this way, there is no need to set a second sub-gate 200. The electrical connection between the first sub-gate 100 and the electrical connector 300 can be achieved by a single conductor 400 set on at least one end of the first sub-gate 100. This is beneficial to further reduce the area of ​​light blocking, increase the area of ​​light receiving of the solar cell, and improve the photoelectric conversion efficiency of the solar cell.

[0125] The photovoltaic module 10 of this application does not require the installation of a main grid solder strip, which reduces the risk that the installation of a main grid on the cell body can easily cause large internal stress in the cell body, leading to microcracks inside the cell body. In addition, the absence of a main grid reduces the area of ​​the cell body blocked by the main grid, thereby increasing the contact area between the cell body and sunlight, which is beneficial to improving the photoelectric conversion efficiency of the cell body.

[0126] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0127] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

Claims

1. A solar cell screen printing plate, characterized in that, The battery cell screen includes: The battery cell itself; Multiple first sub-grids extend along a first direction, and the multiple first sub-grids are spaced apart along a second direction on the battery cell body; The second sub-gate is disposed at at least one end of the first sub-gate along the first direction, and the second sub-gate is electrically connected to multiple first sub-gates respectively; the second sub-gate includes a second positive sub-gate and a second negative sub-gate, and the second positive sub-gate and the second negative sub-gate are both located on the same side of the battery cell body; the second positive sub-gate is electrically connected to one end of multiple first positive sub-gates along the first direction; the second negative sub-gate is electrically connected to one end of multiple first negative sub-gates along the first direction. Multiple pads, the multiple pads being spaced apart along the second direction on the second sub-gate; and First connecting gate and second connecting gate; The battery cell grid includes at least two second positive electrode sub-grids and at least two second negative electrode sub-grids disposed at the same end of the battery cell body along the first direction; the at least two second positive electrode sub-grids are electrically connected through the first connecting grid; the at least two second negative electrode sub-grids are electrically connected through the second connecting grid. The first direction and the second direction intersect each other and are both perpendicular to the thickness direction of the battery cell body.

2. The solar cell screen printing plate according to claim 1, characterized in that, The battery cell body includes a light-incident surface and a back-light surface arranged opposite to each other along its thickness direction; the plurality of first sub-gates include a plurality of first positive sub-gates and a plurality of first negative sub-gates, and the first positive sub-gates and the first negative sub-gates are alternately arranged on the back-light surface of the battery cell body along the second direction.

3. The solar cell screen according to claim 1, characterized in that, The battery cell body includes a light-incident surface and a back-light surface arranged opposite to each other along its thickness direction; the plurality of first sub-gates include a plurality of first positive sub-gates and a plurality of first negative sub-gates, and the plurality of first positive sub-gates and the plurality of first negative sub-gates are arranged at intervals along the second direction on the back-light surface.

4. The solar cell screen as described in claim 1, characterized in that, The cell mesh includes a plurality of first pads and a plurality of second pads, wherein the first pads are electrically connected to at least two second positive sub-gates and the second pads are electrically connected to at least two second negative sub-gates.

5. The solar cell screen according to claim 4, characterized in that, The pads are configured as solder joints, or the pads are made of conductive adhesive, wherein the pads include either the first pad or the second pad.

6. A photovoltaic module, characterized in that, include: Battery cell screen as described in any one of claims 1-5; as well as An electrical connector, at least a portion of which is disposed between two adjacent solar cell screens; In this configuration, the second sub-gate of one of two adjacent cell screens is electrically connected to the electrical connector via a plurality of pads provided on its second sub-gate, and the second sub-gate of the other of the two adjacent cell screens is electrically connected to the electrical connector via a plurality of pads provided on its second sub-gate, thereby achieving electrical connection between the two adjacent cell screens.

7. The photovoltaic module according to claim 6, characterized in that, In each of the aforementioned solar cell grids, the plurality of second sub-grids include a second positive sub-grid and a second negative sub-grid; One of the two adjacent cell screens has its second positive sub-gate electrically connected to the electrical connector via a plurality of pads provided on its second positive sub-gate, and the other of the two adjacent cell screens has its second negative sub-gate electrically connected to the electrical connector via a plurality of pads provided on its second negative sub-gate, thereby realizing the electrical connection between the two adjacent cell screens.

8. The photovoltaic module according to claim 7, characterized in that, The electrical connector includes a plurality of sub-connectors, which are spaced apart along the second direction. The second positive sub-gate of one of two adjacent cell screens is electrically connected to one of the sub-connectors through a plurality of pads provided on its second positive sub-gate, and the second negative sub-gate of the other of the two adjacent cell screens is electrically connected to the sub-connector through a plurality of pads provided on its second negative sub-gate, so as to realize the electrical connection between the two adjacent cell screens.

9. The photovoltaic module according to claim 6, characterized in that, The electrical connector is a tin-coated solder strip or copper foil.

10. The photovoltaic module according to claim 9, characterized in that, The electrical connector is a copper foil, and the electrical connector has a plurality of hollow holes, which are spaced apart along the second direction on the electrical connector.

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