Back contact solar cell, photovoltaic assembly and electrode structure

Abstract

The present application relates to the technical field of photovoltaics. Provided are a back contact solar cell, a photovoltaic assembly and an electrode structure. The electrode structure comprises: an edge first electrode pad; an edge first bus bar, which is located between an edge of the body of a back contact solar cell and the edge first electrode pad and is electrically connected to the edge first electrode pad; first current collection grid lines and second current collection grid lines, which are alternately arranged in a first direction and extend in a second direction; and a first connection line, which extends in the first direction and is only electrically connected to the edge first electrode pad and adjacent first current collection grid lines, wherein the adjacent first current collection grid lines comprise first current collection grid lines, which are distributed adjacent to and / or flush with the edge first electrode pad, in the first direction. In the present application, the first connection line is only electrically connected to the edge first electrode pad and the adjacent first current collection grid lines, and is not electrically connected to other first current collection grid lines; and the first connection line is not of a straight-through type, and can effectively collect carriers in an edge area.

Description

Back contact solar cells and photovoltaic modules and electrode structures

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on November 20, 2023, with application number 202311547660.7 and invention name “Back contact solar cell, photovoltaic module and electrode structure”, the entire contents of which are incorporated by reference into this application. Technical Field

[0002] The present application relates to the field of photovoltaic technology, and in particular to a back-contact solar cell, a photovoltaic module, and an electrode structure. Background Art

[0003] The electrode structure of back-contact solar cells is all on the back of the cell, and there is no electrode blocking the front. Therefore, back-contact solar cells have higher short-circuit current and photoelectric conversion efficiency, and are one of the current technical directions for achieving high-efficiency crystalline silicon cells.

[0004] Figure 1 shows a partial schematic diagram of an electrode structure of a back-contact solar cell in the prior art. Referring to Figure 1 , in the electrode structure of the prior art back-contact solar cell, the busbar lines and the electrode disks are set in a straight-through manner to facilitate current converging and output.

[0005] However, the above arrangement of the electrode structure may easily result in that carriers with polarities opposite to those of the electrode disk at the edge cannot be effectively collected in the edge region.

[0006] Application Contents

[0007] The present application provides a back-contact solar cell, a photovoltaic module and an electrode structure, aiming to solve the problem in existing back-contact solar cells that carriers with opposite polarity to the edge electrode disk cannot be effectively collected in the edge region.

[0008] In a first aspect of the present application, a back-contact solar cell is provided, comprising:

[0009] A first edge electrode disk is located on one side of the edge of the back contact solar cell body;

[0010] an edge first busbar line, located between the edge of the back-contact solar cell body and the edge first electrode disk, and electrically connected to the edge first electrode disk;

[0011] The first collector grid lines and the second collector grid lines are alternately arranged along a first direction and both extend along a second direction; the first direction is different from the second direction;

[0012] a first bonding wire extending along the first direction and electrically connected only to the edge first electrode disk and the adjacent first collector grid line; the adjacent first collector grid line includes: a first collector grid line adjacent to the edge first electrode disk in the first direction, and / or the adjacent first collector grid line includes: a first collector grid line distributed flush with the edge first electrode disk in the first direction;

[0013] The first bonding wire and the adjacent first collector grid line electrically connected thereto are made of the same material; the first bonding wire and the adjacent first collector grid line electrically connected thereto are an integrated structure.

[0014] In the embodiment of the present application, the first jumper wire is only electrically connected to the edge first electrode disk and the aforementioned adjacent first collector grid line, and is not electrically connected to other first collector grid lines. In other words, the first jumper wire is not a straight-through type, and the second collector grid line adjacent to the adjacent first collector grid line does not need to be disconnected, so that the opposite-sex carriers can be collected more effectively, reducing performance loss. At the same time, the first jumper wire is not a straight-through type, and can also reduce hidden cracks. The first jumper wire extending along the first direction electrically connects the edge first electrode disk and the adjacent first collector grid line, realizing the collection and conduction of carriers on the adjacent first collector grid line.

[0015] Optionally, there is a gap between the adjacent first collector grid line and the adjacent edge first collector grid line; the adjacent second collector grid line that is adjacent to the adjacent first collector grid line in the first direction and away from the edge first electrode disk includes: a first extension section extending from the gap to the area defined by the edge first electrode disk, the edge first collector grid line, the first jumper electrically connected to the edge first electrode disk, and the adjacent first collector grid line.

[0016] In the embodiment of the present application, a first bonding wire extending along a first direction electrically connects a first collector grid line that is adjacent to or flush with the edge first electrode disk in the first direction to the edge first electrode disk, thereby eliminating the need for the first collector grid line to be connected to the edge first bus grid line. Therefore, a gap exists between the first collector grid line and the edge first bus grid line. An adjacent second collector grid line that is adjacent to the first collector grid line in the first direction and away from the edge first electrode disk includes a first extension segment extending from the aforementioned gap to an area defined by the edge first electrode disk, the edge first bus grid line, the first bonding wire electrically connected to the edge first electrode disk, and the adjacent first collector grid line. In the present application, by setting up the aforementioned first extension section, carriers with polarity different from that of the first edge electrode disk can be effectively collected in the area defined by the first edge electrode disk, the first edge collector grid line, the first jumper wire electrically connected to the first edge electrode disk, and the first collector grid line adjacent to the first extension section. The first extension section forms an effective loop through the second electrode disk or the second collector grid line electrically connected to the adjacent second collector grid line, thereby realizing the effective collection and conduction of carriers with polarity different from that of the first edge electrode disk in this area, thereby reducing the loss of battery performance.

[0017] Optionally, in the first direction, the first bonding wire extends from the edge first electrode plate to which it is electrically connected to all the adjacent first collector grid lines to which it is electrically connected.

[0018] Optionally, in the first direction, the first bonding wire extends from the adjacent first collector grid line to which it is electrically connected to an interior of the edge first electrode disk to which it is electrically connected.

[0019] Optionally, the number of all first jumper wires electrically connected to one of the edge first electrode disks and one of the adjacent first collector grid lines is greater than or equal to 2; all the first jumper wires include at least: first jumper wires respectively distributed on both sides of the geometric center of the edge first electrode disk; in the second direction, the distance between the two first jumper wires and the geometric center of the edge first electrode disk is greater than 0.3 mm.

[0020] Optionally, in the first direction, a dimension of the first overlapped line that exceeds all the portions of the first collector grid lines to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm.

[0021] Optionally, in the first direction, a size of a portion of the first overlap line extending to the interior of the edge first electrode disk to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm.

[0022] Optionally, the shape of the first overlap line is: an S-shape extending along the first direction; or the shape of the first overlap line is: a Z-shape extending along the first direction.

[0023] Optionally, the line width of the first bonding line is greater than or equal to the line width of the adjacent first collector grid line to which it is electrically connected.

[0024] Optionally, the edge first electrode disk includes: an edge negative electrode disk;

[0025] The first edge busbar lines include: edge negative busbar lines;

[0026] The first collector grid line includes a negative electrode collector grid line.

[0027] Optionally, each of the first bonding wires electrically connected to one of the edge first electrode disks is symmetrical about the geometric center of the edge first electrode disk.

[0028] Optionally, the edge first electrode disk and the first collector grid line are made of different materials.

[0029] Optionally, the first extension segment includes: a first portion extending along the first direction and a second portion extending along the second direction.

[0030] In a second aspect of the present application, a back-contact solar cell is provided, comprising: a back-contact solar cell body, and an electrode structure located on the backlight surface of the back-contact solar cell body, such as any of the aforementioned back-contact solar cells.

[0031] According to a third aspect of the present application, another back-contact solar cell is provided, comprising: a first sub-sheet and a second sub-sheet;

[0032] The first sub-sheet includes: a first sub-back contact solar cell body, and a first electrode structure located on the backlight side of the first sub-back contact solar cell body; the first electrode structure is any of the aforementioned electrode structures of the back contact solar cell;

[0033] The second sub-sheet includes: a second sub-back contact solar cell body, and a second electrode structure located on the backlight surface of the second sub-back contact solar cell body;

[0034] The second electrode structure comprises:

[0035] a second edge electrode disk, collinear with the first edge electrode disk in the first direction;

[0036] an edge electrode frame, located outside the edge second electrode disk and electrically connected to the edge second electrode disk;

[0037] a second edge busbar line, collinear with the first edge busbar line in the first direction;

[0038] First collector grid lines and second collector grid lines are alternately arranged along the first direction and both extend along the second direction; the first direction is different from the second direction; the second collector grid lines are aligned and electrically connected to the edge electrode frame; the aligned second collector grid lines include: second collector grid lines aligned with the edge electrode frame in the first direction;

[0039] The second bonding wire extends along the first direction and is electrically connected only to the edge electrode frame and the adjacent second collector grid line; the adjacent second collector grid line includes: the second collector grid line adjacent to the edge electrode frame in the first direction.

[0040] In a fourth aspect of the present application, a photovoltaic assembly is provided, comprising: a plurality of the aforementioned back-contact solar cells, and a conductive interconnect electrically connected to the edge first electrode plate.

[0041] Optionally, the conductive interconnect extends along the first direction;

[0042] The first jumper wire and the adjacent first collector grid line electrically connected thereto are an integrated structure. In the second direction, the distance between the two first jumpers and the geometric center of the edge first electrode disk is greater than half the size of the conductive interconnect in the second direction.

[0043] In a fifth aspect of the present application, a photovoltaic module is provided, comprising: a plurality of cell strings; the cell strings comprising: a conductive interconnection member, and a plurality of the aforementioned first sub-sheets and second sub-sheets;

[0044] In the battery string, the edge first electrode disk of the first sub-sheet and the edge second electrode disk of the second sub-sheet are connected in series via the conductive interconnector.

[0045] Any photovoltaic module, any of the aforementioned back-contact solar cell electrode structures, and any of the aforementioned back-contact solar cells have the same or similar beneficial effects. The relevant or similar aspects of the five can be referenced to each other. In order to avoid repetition, the relevant aspects will not be repeated. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0047] FIG1 shows a partial schematic diagram of an electrode structure of a back-contact solar cell in the prior art;

[0048] FIG2 shows a partial schematic diagram of the electrode structure of the first back-contact solar cell in an embodiment of the present application;

[0049] FIG3 shows a partial schematic diagram of the electrode structure of a second back-contact solar cell in an embodiment of the present application;

[0050] FIG4 shows a partial schematic diagram of the electrode structure of a third back-contact solar cell according to an embodiment of the present application;

[0051] FIG5 shows a partial schematic diagram of a knotless electrode screen;

[0052] FIG6 shows a partial schematic diagram of a sub-grid corresponding to a first collector grid line in an embodiment of the present application;

[0053] FIG7 shows a partial schematic diagram of another sub-grid corresponding to the first collector grid line in an embodiment of the present application;

[0054] FIG8 shows a partial schematic diagram of the electrode structure of a fourth back-contact solar cell according to an embodiment of the present application;

[0055] FIG9 shows a partial schematic diagram of the electrode structure of the fifth back-contact solar cell in an embodiment of the present application;

[0056] FIG10 shows a partial schematic diagram of the electrode structure of the sixth back-contact solar cell in an embodiment of the present application.

[0057] Description of the accompanying figures:

[0058] 1-edge first electrode disk, 2-edge first bus grid line, 3-first collector grid line, 32-adjacent to the first collector grid line, 4-second collector grid line, 42-adjacent to the second collector grid line, 41-first extension section, 5-first overlap line, 6-edge of the back contact solar cell body, 7-electrode frame, 71-edge electrode frame, 8-second bus grid line, 81-edge second bus grid line, 9-mesh, 10-printed first collector grid pattern, 11-mesh knot, 12-second electrode disk, 121-edge second electrode disk, 13-first sub-sheet, 14-second sub-sheet, 15-second overlap line, 31-second extension section. Specific embodiments

[0059] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0060] Those skilled in the art should understand that, in the disclosure of this application, the terms "first", "second", "third", "fourth", "fifth", etc. are only used to distinguish different structures, and do not limit the number, connection relationship, etc. of specific structures; in addition, the directions or positional relationships indicated by "longitudinal", "transverse", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, which 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 direction, be constructed and operated in a specific direction. Therefore, the above terms cannot be understood as limiting this application.

[0061] 1 , in the existing electrode structure, the first edge electrode disk 1 and the first collector grid line colinear with the first edge electrode disk 1 are set to be straight-through, and in order to avoid short circuit, the second collector grid line 4 of the opposite sex is disconnected next to the first collector grid line, resulting in the second collector grid line 4 of the opposite sex indicated by the arrow at the edge of the back contact solar cell body being unable to form an effective loop, that is, the carriers with opposite polarity to the first edge electrode disk 1 in the edge region cannot be effectively collected, resulting in a great loss of performance.

[0062] Figure 2 shows a partial schematic diagram of the electrode structure of a first back-contact solar cell according to an embodiment of the present application. Figure 3 shows a partial schematic diagram of the electrode structure of a second back-contact solar cell according to an embodiment of the present application. Figure 4 shows a partial schematic diagram of the electrode structure of a third back-contact solar cell according to an embodiment of the present application. Referring to Figures 2, 3, and 4, the electrode structure of the back-contact solar cell may include: a first edge electrode disk 1 located on one side of an edge 6 of the back-contact solar cell body. The back-contact solar cell body may include a base and an emitter. The base corresponds to one of a P-type region and an N-type region, and the emitter corresponds to the other of a P-type region and an N-type region. The P-type and N-type regions of the back-contact solar cell body are arranged in an interdigitated pattern. The main function of the back-contact solar cell body is to generate and separate charge carriers. The electrode structure of the back-contact solar cell is primarily used to collect and conduct charge carriers. The back-contact solar cell may also include: an electrode structure located on the backlight side of the solar cell body. During normal operation of the back-contact solar cell, the surface of the back-contact solar cell body that primarily receives light is the light-facing side, with the backlight side facing the light-facing side. The specific type of solar cell is not limited; for example, the solar cell may be an HPBC (hybrid passivated back contact cell).

[0063] The edge 6 of the back contact solar cell body may refer to a region on one side of a side of the back contact solar cell body. The side of the back contact solar cell body may have a portion parallel to the extending direction of the busbar lines.

[0064] The electrode structure of the back-contact solar cell also includes: an edge first busbar line 2, which is located between the edge 6 of the back-contact solar cell body and the edge first electrode disk 1, and is electrically connected to the edge first electrode disk 1. In other words, the edge first busbar line 2 is located between the edge 6 of the back-contact solar cell body and the edge first electrode disk 1, and is electrically connected to the edge first electrode disk 1. In Figures 2 and 3, the edge first busbar line 2 includes a portion extending in the vertical direction, and a portion extending in the horizontal direction and electrically connected to the edge first electrode disk 1.

[0065] The electrode structure of the back-contact solar cell also includes: first collector grid lines 3 and second collector grid lines 4, which are arranged alternately along a first direction L1. Specifically, along the vertically extending first direction L1, one first collector grid line 3 and one second collector grid line 4 are arranged alternately. Both the first collector grid lines 3 and the second collector grid lines 4 extend along a second direction L2. The first direction L1 is different from the second direction L2, and the angle between the first direction L1 and the second direction L2 is not specifically limited. For example, in Figures 2 and 3, the first direction L1 and the second direction L2 are perpendicular.

[0066] The electrode structure of the back-contact solar cell also includes: a first overlap line 5, extending along the aforementioned first direction L1. The first collector grid line 32 is adjacent to the first collector grid line 3 that is adjacent to the edge first electrode disk 1 in the first direction L1. For example, in Figures 2 and 3, the first collector grid line 3 that is adjacent to the edge first electrode disk 1 in the first direction L1 is adjacent to the first collector grid line 32. And / or, the first collector grid line 32 is adjacent to the first collector grid line 3 that is distributed flush with the edge first electrode disk 1 in the first direction L1. For example, in Figure 4, the first collector grid line 3 that is distributed flush with the edge first electrode disk 1 on the upper side in the first direction L1 is adjacent to the first collector grid line 32. In Figure 4, the first collector grid lines 3 that are distributed flush with the edge first electrode disk 1 and are adjacent to the lower side in the first direction L1 are all adjacent to the first collector grid line 32. The first bonding wire 5 is electrically connected only to the edge first electrode disk 1 and the aforementioned adjacent first collector grid line 32. As shown in Figures 2 and 3, the first bonding wire 5 is electrically connected only to the edge first electrode disk 1 and the adjacent first collector grid line 32. In Figure 4, the first bonding wire 5 is electrically connected only to the edge first electrode disk 1 and the adjacent first collector grid line 32.

[0067] In response to the aforementioned technical problems, in this application, the first jumper wire 5 is only electrically connected to the edge first electrode disk 1 and the aforementioned adjacent first collector grid line 32, and is not electrically connected to other first collector grid lines. In other words, the first jumper wire 5 is not a straight-through type, and the second collector grid line 4 adjacent to the adjacent first collector grid line 32 does not need to be disconnected, so that the opposite-sex carriers can be collected more effectively, reducing performance loss. Moreover, the first jumper wire is not a straight-through type, which can also reduce hidden cracks. At the same time, the first jumper wire 5 extending along the first direction L1 electrically connects the edge first electrode disk 1 and the adjacent first collector grid line 32, realizing the collection and conduction of carriers on the adjacent first collector grid line.

[0068] Since the aforementioned adjacent first collector grid lines 32 are all directly electrically connected to the edge first electrode disk 1 through the aforementioned first jumper wire 5, the aforementioned adjacent first collector grid lines 32 do not need to be electrically connected to the edge first bus grid line 2. Therefore, in the electrode structure of the back-contact solar cell, there is a gap between the adjacent first collector grid line 32 and its adjacent edge first bus grid line 2. The adjacent second collector grid line 42 adjacent to the adjacent first collector grid line 32 in the first direction L1 and away from the edge first electrode disk 1 includes: a first extension section 41 extending from the aforementioned gap to the area defined by the edge first electrode disk 1, the edge first bus grid line 2, the first jumper wire 5 electrically connected to the edge first electrode disk 1, and the adjacent first collector grid line 32. In response to the aforementioned technical problems, in the present application, the adjacent first collector grid lines 32 are all directly electrically connected to the edge first electrode disk 1 through the aforementioned first bonding wire 5. Therefore, the adjacent first collector grid lines 32 do not need to be electrically connected to the edge first bus grid line 2. Therefore, in the electrode structure of the back-contact solar cell, there is a gap between the adjacent first collector grid line 32 and the adjacent edge first bus grid line 2. By setting the aforementioned first extension section 41, carriers with different polarities from the edge first electrode disk 1 can be effectively collected in the area defined by the edge first electrode disk 1, the edge first bus grid line 2, the first bonding wire 5 electrically connected to the edge first electrode disk 1, and the adjacent first collector grid line 32. The first extension section 41 forms an effective loop through the second electrode disk 12 or the second bus grid line 8 electrically connected to the adjacent second collector grid line 42, thereby achieving effective collection and conduction of carriers with different polarities from the edge first electrode disk 1 in this area, further reducing the loss of battery performance.

[0069] It should be noted that the shape of the aforementioned first edge electrode plate 1 is not specifically limited. For example, its orthographic projection on the back-contact solar cell body can be circular, hexagonal, etc. For example, referring to Figures 2 to 4 , the orthographic projection of the first edge electrode plate 1 on the back-contact solar cell body is rectangular.

[0070] 3 , the first bonding wire 5 and the adjacent first collector grid line 32 to which it is electrically connected are integrally formed, and the two are an integral structure. The integral structure here can mean that the first bonding wire 5 and the adjacent first collector grid line 32 to which it is electrically connected are printed together, which is convenient to process and has high production efficiency. In this case, the first bonding wire 5 and the adjacent first collector grid line 32 to which it is electrically connected are made of the same material. In this case, optionally, in the aforementioned first direction L1, the first bonding wire 5 extends from the adjacent first collector grid line 32 to which it is electrically connected to the interior of the edge first electrode disk 1 to which it is electrically connected. Since the edge first electrode disk 1 and the first collector grid line 3 are usually processed in batches, the portion extending to the interior of the edge first electrode disk 1 to which it is electrically connected can avoid the problem of the first bonding wire 5 being unable to effectively electrically connect to the edge first electrode disk 1 due to processing errors between the two. Here, the portion extending to the interior of the edge first electrode disk 1 to which it is electrically connected needs to ensure that even if there are processing errors between the two, the first bonding wire 5 can still effectively electrically connect to the edge first electrode disk 1. The adjacent first collector grid line can realize the collection of carriers. Since the first bonding wire and the adjacent first collector grid line electrically connected to it are made of the same material and the two are an integral structure or integrally formed, the electrical connection between the two and the silicon-containing layer of the battery cell is the same. Therefore, the first bonding wire can also realize the collection of carriers.

[0071] More specifically, the material of the first jumper wire is the same as the material of the first collector grid line that is electrically connected to it, and the two are an integral structure or integrally formed. Then, the first jumper wire and the first collector grid line that are adjacent to it can both form contact with the silicon-containing layer, and the first jumper wire can also collect carriers. The first jumper wire can collect carriers at its location and its surrounding locations, which increases the carrier collection area and helps to improve the carrier collection effect. That is, the portion of the first jumper wire located outside the edge first electrode disk can collect carriers, which helps to improve the carrier collection effect and can improve the efficiency of the back-contact solar cell. In addition, the first jumper wire makes better ohmic contact with the silicon-containing layer and the edge first electrode disk. The first jumper wire and the first collector grid line that are adjacent to it can both form a metal alloy with the silicon-containing layer at the contact interface. More specifically, the portion of the first jumper wire located outside the edge first electrode disk can improve its ohmic contact effect with the silicon-containing layer and can also improve its ohmic contact effect with the edge first electrode disk, which can improve the efficiency of the back-contact solar cell. On the other hand, the first jumper wire and the first collector grid line electrically connected to it are made of the same material. The first jumper wire and the first collector grid line electrically connected to it are an integrated structure or an integrated molding, which is convenient to process and has high production efficiency. The first jumper wire and the first collector grid line electrically connected to it have good mechanical properties and are more firm and reliable.

[0072] Optionally, referring to Figures 2 to 4, the first extension segment 41 includes: a first part extending along the first direction L1, and a second part extending along the second direction L2. The first extension segment 41 is distributed in more directions and thus covers a wider area. The first extension segment 41 can effectively collect carriers in a wider area and with different polarity from the edge first electrode disk 1.

[0073] Optionally, referring to Figures 2 and 4, in the aforementioned first direction L1, the first jumper wire 5 extends from the edge first electrode disk 1 to which it is electrically connected to all adjacent first collector grid lines 32 to which it is electrically connected. Since the edge first electrode disk 1 and the first collector grid lines 3 are usually processed in batches, the aforementioned excess portion can avoid the problem that the first jumper wire 5 cannot be effectively electrically connected to each adjacent first collector grid line 32 due to processing errors between the two. The excess portion here needs to ensure that even if there are processing errors between the two, the first jumper wire 5 can still be effectively electrically connected to each adjacent first collector grid line 32. It should be noted that there is no specific limitation on the line width of the first jumper wire 5. For example, referring to Figures 2 and 4, the line width of the first jumper wire 5 can be smaller than the size of the edge first electrode disk 1 in the first direction L1 or the second direction L2. Compared with directly using the edge first electrode disk 1 to electrically jumper the adjacent first collector grid lines 32 adjacent to each other in the first direction L1, the use of a first jumper wire 5 with a smaller line width in this application can reduce costs.

[0074] Optionally, in the aforementioned first direction L1, the dimension of the portion of the first bonding line 5 that extends beyond all adjacent first collector grid lines 32 to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm. This ensures that, even if there are manufacturing errors between the edge first electrode disk 1 and the first collector grid lines 3, the first bonding line 5 can still effectively electrically connect to each adjacent first collector grid line 32. Furthermore, the dimension of this portion is not excessively large, thus avoiding waste. For example, referring to FIG2 , in the aforementioned first direction L1, the dimension of the portion of the first bonding line 5 that extends beyond all adjacent first collector grid lines 32 to which it is electrically connected is 0.12 mm.

[0075] Optionally, in the aforementioned first direction L1, the dimension of the portion of the first bonding wire 5 extending into the interior of the edge first electrode disk 1 to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm. This ensures that, even if there are manufacturing errors between the edge first electrode disk 1 and the first collector grid line 3, the first bonding wire 5 can still effectively electrically connect to the edge first electrode disk 1. Furthermore, the dimension of this portion is not excessively large, thereby avoiding waste. For example, referring to FIG3 , in the aforementioned first direction L1, the dimension of the portion of the first bonding wire 5 extending into the interior of the edge first electrode disk 1 to which it is electrically connected is 0.12 mm.

[0076] Optionally, referring to FIG3 , the first bonding wire 5 and the adjacent first collector grid line 32 electrically connected thereto are integrally formed, and the number of all first bonding wires 5 electrically connected to both an edge first electrode disk 1 and an adjacent first collector grid line 32 is greater than or equal to two. For example, in FIG3 , there are two first bonding wires 5 electrically connected to both an edge first electrode disk 1 and an adjacent first collector grid line 32. All first bonding wires 5 electrically connected to both an edge first electrode disk 1 and an adjacent first collector grid line 32 include at least two first bonding wires 5 distributed on either side of the geometric center of the edge first electrode disk 1, wherein the distance between these two first bonding wires 5 and the geometric center of the edge first electrode disk 1 in the aforementioned second direction L2 is greater than half the dimension of the conductive interconnect in the second direction. Specifically, the first bonding wire 5 and the adjacent first collector grid line 32 electrically connected thereto are integrally formed, and the first bonding wire 5 and the adjacent first collector grid line 32 electrically connected thereto are made of the same material. Typically, the materials of the collector grid lines are not drought-resistant or have poor welding performance. The welding position of the conductive interconnect, such as the welding ribbon, usually extends along the aforementioned first direction L1 and passes through the geometric center of the edge first electrode disk 1 and its vicinity. If the first bonding wire 5 is set at a position collinear with the geometric center of the edge first electrode disk 1 and its vicinity, the first bonding wire 5 is likely to be damaged during the welding process, causing the electrical connection between the first bonding wire 5 and the edge first electrode disk 1 to fail. Therefore, in the present application, the distance between the two first bonding wires 5 and the geometric center of the edge first electrode disk 1 is greater than half of the size of the conductive interconnect in the second direction, that is, the two first bonding wires 5 are prevented from being collinear with the geometric center of the edge first electrode disk 1 and its vicinity. At the same time, during the welding process, the conductive interconnect may shift in the second direction L2. Therefore, in the present application, the two first bonding wires 5 are distributed on both sides of the geometric center of the edge first electrode disk 1, and in the aforementioned second direction L2, the distance between the two first bonding wires 5 and the geometric center of the edge first electrode disk 1 is greater than half of the size of the conductive interconnect in the second direction. Therefore, no matter which side the conductive interconnect shifts in the second direction L2, at least one of the two first bonding wires 5 will remain intact and can still provide a reliable electrical connection between the first bonding wire 5 and the edge first electrode disk 1. It should be noted that when the first bonding wire 5 and the adjacent first collector grid line 32 electrically connected thereto are an integral structure, the specific number of all first bonding wires 5 electrically connected to one edge first electrode disk 1 and one adjacent first collector grid line 32 is not limited when it is greater than or equal to 2.

[0077] That is, the first bonding wire 5 and the adjacent first collector grid line 32 electrically connected thereto are integrally structured. In the aforementioned second direction L2, the distance between the two first bonding wires 5 and the geometric center of the edge first electrode disk 1 to which they are electrically connected is greater than half the dimension (i.e., width) of the aforementioned conductive interconnect in the second direction L2. Therefore, regardless of the direction in which the conductive interconnect shifts in the second direction L2, at least one of the two first bonding wires 5 will remain intact, maintaining a reliable electrical connection between the first bonding wire 5 and the edge first electrode disk 1. Optionally, in the second direction, the distance between the two first bonding wires and the geometric center of the edge first electrode disk is greater than 0.3 mm. More specifically, the dimension (i.e., width) of a commonly used conductive interconnect in the second direction L2 is 0.6 mm. For commonly used conductive interconnects, regardless of the direction in which the conductive interconnect shifts in the second direction L2, at least one of the two first bonding wires 5 will remain intact, maintaining a reliable electrical connection between the first bonding wire 5 and the edge first electrode disk 1.

[0078] For example, in Figure 3, two first bonding wires 5 electrically connected to an edge first electrode disk 1 and a first collector grid line 32 adjacent to the edge are respectively distributed on both sides of the geometric center of the edge first electrode disk 1 to which they are electrically connected, and the distance between the two first bonding wires 5 and the geometric center of the edge first electrode disk 1 to which they are electrically connected is greater than 0.3 mm.

[0079] More specifically, the first bonding wire and the adjacent first collector grid line electrically connected thereto are made of the same material, and the two are integrally structured or integrally formed. The collector grid line material is typically not drought-resistant or has poor welding performance. The welding position of the conductive interconnect (e.g., a soldering ribbon) typically extends along the first direction and passes through or near the geometric center of the edge first electrode disk. The first bonding wire and the adjacent first collector grid line electrically connected thereto are made of the same material, and the two are integrally structured or integrally formed, ensuring that the first bonding wires, respectively distributed on either side of the geometric center of the edge first electrode disk, are significantly distanced from the geometric center of the edge first electrode disk. During the welding process, the conductive interconnect may shift in the second direction. Because the distance between the first bonding wires, respectively distributed on either side of the geometric center of the edge first electrode disk, and the geometric center of the edge first electrode disk in the second direction is greater than half of the dimension (i.e., width) of the conductive interconnect in the second direction, regardless of the direction in which the conductive interconnect shifts in the second direction, at least one of the two first bonding wires will remain intact, maintaining a reliable electrical connection between the first bonding wire and the edge first electrode disk. More specifically, the dimension (i.e., width) of the currently commonly used conductive interconnect in the second direction is 0.6 mm. Therefore, in the second direction, the distance between the two first lap wires and the geometric center of the edge first electrode disk is greater than 0.3 mm. For the currently commonly used conductive interconnect, no matter which side the conductive interconnect is offset in the second direction, at least one of the two first lap wires will not fail, and can still meet the requirements of reliable electrical connection between the first lap wire and the edge first electrode disk. That is to say, on the one hand, in the process of conductive interconnection using conductive interconnects, the first bonding wires are easily damaged at the position of the conductive interconnection, and the conductive interconnection may be offset in the second direction. The first bonding wires are respectively distributed on both sides of the geometric center of the edge first electrode disk, and in the second direction, the distance between the two first bonding wires and the geometric center of the edge first electrode disk is greater than half of the size of the currently commonly used conductive interconnection in the second direction. No matter which side the conductive interconnection is offset in the second direction, the distance between at least one first bonding wire on the other side and the conductive interconnection must be greater than 0. Therefore, at least one first bonding wire on the other side must not be located at the position where the conductive interconnection passes, and at least one first bonding wire on the other side must not be damaged.That is to say, in the conductive interconnection process, using the currently commonly used conductive interconnection parts, when the first jumper wire is easily damaged at the conductive interconnection position and the conductive interconnection part is offset in the second direction, at least one first jumper wire on the other side will inevitably be retained and will not fail, and can still meet the requirements of reliable electrical connection between the first jumper wire and the edge first electrode disk. On the other hand, the first jumper wire and the adjacent first collector grid line electrically connected to it are made of the same material, and the first jumper wire and the adjacent first collector grid line electrically connected to it are an integrated structure or an integrated molding, which is convenient to process and has high production efficiency. The first jumper wire and the adjacent first collector grid line electrically connected to it have good mechanical properties and are more firm and reliable. In summary, the present application can not only ensure that when there are processing errors among the edge first electrode disk, the first collector grid line and the conductive interconnection part, the first jumper wire can still be effectively electrically connected to the edge first electrode disk, but also is convenient to process, has high production efficiency, and is firm and reliable.

[0080] Optionally, the first jumper wire 5 and the adjacent first collector grid line 32 electrically connected thereto are an integral structure, and the shape of the first jumper wire 5 can be: an S-shape extending along the aforementioned first direction L1; or, the shape of the first jumper wire 5 can be: a Z-shape extending along the first direction L1. Figure 5 shows a partial schematic diagram of a knotless electrode screen. Specifically, the knotless screen shown in Figure 5 is often used for printing collector grid lines. In Figure 5, 9 is mesh, 10 is the pattern of the printed first collector grid line 3, and the intersection surrounded by the circle is the knot 11. The grid line printing of this screen in the first direction L1 is easily blocked by the grid line, resulting in printing abnormalities. Figure 6 shows a partial schematic diagram of a sub-screen corresponding to the adjacent first collector grid line in an embodiment of the present application. Figure 7 shows a partial schematic diagram of another sub-screen corresponding to the adjacent first collector grid line in an embodiment of the present application. Therefore, in order to match the knotless screen, when the first overlap line 5 and the adjacent first collector grid line 32 electrically connected thereto are an integrated structure, the first overlap line 5 extending along the first direction L1 can adopt the S-shape extending along the first direction L1 as shown in Figure 6, or the first overlap line 5 extending along the first direction L1 can adopt the Z-shape extending along the first direction L1 as shown in Figure 7, to prevent local printing abnormalities and improve printing quality.

[0081] Optionally, when the first bonding line 5 and the adjacent first collector grid line 32 electrically connected thereto are integrally structured, the line width of the first bonding line 5 is greater than or equal to the line width of the adjacent first collector grid line 32 electrically connected thereto. Specifically, based on the aforementioned knotless screen printing, the above line width design is easy to implement in printing. There is no specific limitation on the difference between the two line widths.

[0082] Optionally, the edge first electrode disk 1 includes an edge negative electrode disk; the edge first busbar line 2 includes an edge negative busbar line; the first collector line 3 includes a negative collector line; and the second collector line 4 includes a positive collector line. Figure 8 shows a partial schematic diagram of the electrode structure of a fourth back-contact solar cell according to an embodiment of the present application. During use, the cell in Figure 8 can be sliced ​​along its centerline to form upper and lower sub-sheets, with the first sub-sheet 13 and the second sub-sheet 14 connected to form a cell string. Figure 9 shows a partial schematic diagram of the electrode structure of a fifth back-contact solar cell according to an embodiment of the present application. Figure 10 shows a partial schematic diagram of the electrode structure of a sixth back-contact solar cell according to an embodiment of the present application. Figure 9 is an enlarged schematic diagram of the third dotted circled portion from top to bottom along the L1 direction in Figure 8. Figure 10 is an enlarged schematic diagram of the lowest dotted circled portion from top to bottom along the L1 direction in Figure 8. An enlarged schematic diagram of the first dotted circled portion from top to bottom along the L1 direction in Figure 8 is shown in Figure 2. In FIG8 , an enlarged schematic diagram of the portion encircled by the second dotted circle from top to bottom along the L1 direction is shown in FIG4 . Referring to FIG8 to FIG10 , the positive electrode collector grid line and the positive electrode bus grid line can be made of materials such as aluminum paste to reduce costs. However, aluminum has poor welding performance or no weldability. In order to improve welding performance, an electrode frame 7 such as an aluminum frame is usually provided on the outside of the second electrode disk 12. In this case, the design of the positive electrode disk or the second electrode disk 12, the second collector grid line 4, the second bus grid line 8, etc. is different from the aforementioned method. Therefore, the edge first electrode disk 1 includes: an edge negative electrode disk; the edge first bus grid line 2 includes: an edge negative bus grid line; and the first collector grid line 3 includes: a negative collector grid line, which can appropriately reduce costs.

[0083] Optionally, referring to Figures 2 and 3, the first bonding wires 5 electrically connected to an edge first electrode disk 1 are symmetrical about the geometric center of the edge first electrode disk 1. On the one hand, the electrode structure has a beautiful appearance, and on the other hand, the edge first electrode disk 1 is more balanced in collecting carriers.

[0084] Optionally, the materials of the edge first electrode disk 1 and the first collector grid line 3 are different. More specifically, the edge first electrode disk 1 is subsequently used for welding, so its material can be more inclined to improve its welding performance, etc. That is, the welding resistance of the material of the edge first electrode disk 1 is higher than the welding resistance of the material of the first collector grid line 3. For example, the mass content of the inorganic metal oxide in the edge first electrode disk 1 can be higher than the content of the inorganic metal oxide in the first collector grid line 3. For example, the edge first electrode disk 1 and the first collector grid line 3 can both be prepared from silver paste, and the mass content of silver in the two is different. The different materials of the edge first electrode disk 1 and the first collector grid line 3 are conducive to adjustment according to their respective required performance, so that the battery performance is better.

[0085] For example, the first electrode pad and the first busbar line can be printed at once, and the first collector grid line 3 and the first bonding line 5 can be printed at once. The paste used to print the first electrode pad and the first busbar line is silver paste, and the silver content of the silver paste can be 73% to 83% by weight. The paste used to print the first collector grid line 3 and the first bonding line 5 is also silver paste, and the silver content of the silver paste can be 89% to 92% by weight.

[0086] The application also provides a back-contact solar cell, which may include: a back-contact solar cell body, which may include a base and an emitter. The definitions of the base and the emitter, the main functions of the back-contact solar cell body, and the main functions of the electrode structure of the back-contact solar cell can all refer to the aforementioned relevant records. In order to avoid repetition, they will not be repeated here. The back-contact solar cell may also include: an electrode structure located on the backlight surface of the back-contact solar cell body, such as any of the aforementioned back-contact solar cells. There is no specific limitation on the type of the back-contact solar cell. During normal operation of the back-contact solar cell, the surface of the back-contact solar cell body that mainly receives light is the light-facing surface, and the backlight surface is opposite to the light-facing surface. The back-contact solar cell has the same or similar beneficial effects as any of the aforementioned back-contact solar cell electrode structures, and the related or similar points between the two can be referenced to each other. In order to avoid repetition, they will not be repeated here.

[0087] The application also provides a photovoltaic module, which includes the aforementioned back-contact solar cell and a conductive interconnector electrically connected, such as welded, to the edge first electrode disk 1 in the electrode structure of the back-contact solar cell.

[0088] Optionally, the conductive interconnect extends along the aforementioned first direction L1. The conductive interconnect can be a welding strip, etc., and the specific form of the conductive interconnect is not limited. Referring to Figure 3, the first jumper wire 5 and the adjacent first collector grid line 32 electrically connected thereto are an integral structure. In the aforementioned second direction L2, the distance between the two first jumpers 5 and the geometric center of the edge first electrode disk 1 to which they are electrically connected is greater than half of the size (i.e., width) of the aforementioned conductive interconnect in the second direction L2. Therefore, no matter which side the conductive interconnect is offset in the second direction L2, at least one of the two first jumpers 5 will not fail, and a reliable electrical connection between the first jumper wire 5 and the edge first electrode disk 1 can still be achieved.

[0089] 8 , the present application also provides another back-contact solar cell, which may include a first sub-sheet 13 and a second sub-sheet 14 . Whether the first sub-sheet 13 and the second sub-sheet 14 are equal in size is not limited. For example, in FIG8 , the first sub-sheet 13 and the second sub-sheet 14 are equal in size and are two halves.

[0090] The first sub-sheet 13 includes: a first sub-back contact solar cell body, and a first electrode structure located on the backlight side of the first sub-back contact solar cell body, and the first electrode structure is such as any of the aforementioned electrode structures of the back contact solar cell. As mentioned above, in FIG8 , for the first sub-sheet 13, an enlarged schematic diagram of the first dotted circled portion from top to bottom along the L1 direction is shown in FIG2 . In FIG8 , an enlarged schematic diagram of the second dotted circled portion from top to bottom along the L1 direction is shown in FIG4 . The first sub-back contact solar cell body and the first electrode structure of the first sub-sheet 13 have the same or similar beneficial effects as any of the aforementioned back contact solar cell bodies and electrode structures, and the related parts of the two can be referenced to each other. In order to avoid repetition, they will not be described here.

[0091] As shown in Figure 8 , the second sub-sheet 14 includes: a second sub-back-contact solar cell body, and a second electrode structure located on the backlight side of the second sub-back-contact solar cell body. Figure 9 is an enlarged schematic diagram of the first dotted circled portion of the second sub-sheet 14 along the L1 direction from top to bottom in Figure 8 . Figure 10 is an enlarged schematic diagram of the bottommost dotted circled portion of the second sub-sheet 14 along the L1 direction in Figure 8 .

[0092] 9 and 10 , the second electrode structure includes: an edge second electrode disk 121, which is collinear with the aforementioned edge first electrode disk 1 in the first direction L1; an edge electrode frame 71, which is located outside the edge second electrode disk 121 and electrically overlaps with the edge second electrode disk 121; and an edge second bus bar line 81, which is collinear with the aforementioned edge first bus bar line 2 in the first direction L1.

[0093] 9 and 10 , the second electrode structure further includes: a first collector grid line 3 and a second collector grid line 4 , both of which are alternately arranged along a first direction L1 and both extend along a second direction L2 , where the first direction L1 is different from the second direction L2 . For reference, the aforementioned related records may be referred to, and will not be elaborated on herein to avoid repetition.

[0094] 9 , the second electrode structure further includes: a second overlap line 15, extending along the first direction L1, and electrically connected only to the edge electrode frame 71 and the adjacent second collector grid line. The adjacent second collector grid line includes: a second collector grid line 4 adjacent to the edge electrode frame 71 in the aforementioned first direction L1. Referring to Figures 9 and 10, in the first direction L1, the second collector grid line 4 distributed flush with the edge electrode frame 71 is a flush second collector grid line, and the edge electrode frame 71 is electrically connected to the flush second collector grid line. Through the above-mentioned arrangement, the direct-through design with the edge second electrode disk 121 in the first direction L1 is also avoided in the second sub-sheet 14, and carriers with opposite polarity to the edge second electrode disk 121 in the edge area can also be effectively collected, and hidden cracks can be reduced. The back-contact solar cell has the same or similar beneficial effects as any of the aforementioned electrode structures, and the relevant parts can be referenced to each other. In order to avoid repetition, they will not be described here.

[0095] Optionally, there is a gap between the adjacent second collector grid line and the flush second collector grid line and the adjacent edge second collector grid line 81, and the adjacent first collector grid line that is adjacent to the adjacent second collector grid line and the flush second collector grid line in the first direction L1 and away from the edge electrode frame 71 includes: a second extension section 31 extending from the gap to the edge electrode frame 71, the edge second collector grid line 81, and the second jumper line 15 electrically connected to the edge electrode frame 71, and the area defined by the adjacent first collector grid line and the flush second collector grid line. As shown in FIG9 , on the upper side of the first direction L1, the adjacent first collector grid line includes a second extension segment 31 extending from the gap to the edge electrode frame 71, the edge second bus grid line 81, and the region defined by the second bonding wire 15 electrically connected to the edge electrode frame 71, the adjacent first collector grid line, and the aligned second collector grid line. In FIG9 , on the lower side of the first direction L1, the adjacent first collector grid line includes a second extension segment 31 extending from the gap to the region defined by the edge electrode frame 71, the edge second bus grid line 81, and the aligned second collector grid line. This second extension segment 31 forms an effective loop with the first electrode disk or first bus grid line electrically connected to the adjacent first collector grid line, effectively collecting and conducting carriers of different polarity from the edge second electrode disk 121 within this region, thereby reducing battery performance loss.

[0096] Optionally, the second extension section 31 here may also include: a portion extending along the first direction L1 and a portion extending along the second direction L2, which can effectively collect and conduct carriers with different polarities from the edge second electrode disk 121 in a wider area.

[0097] The present application also provides another photovoltaic module, comprising: a plurality of cell strings, each cell string comprising: a conductive interconnection member, and the aforementioned first sub-sheet 13 and second sub-sheet 14. In the cell string, the first electrode plate 1 at the edge of the first sub-sheet 13 and the second electrode plate 121 at the edge of the second sub-sheet 14 are connected in series via the conductive interconnection member, which may also be a welding ribbon, etc., and the conductive interconnection member also extends along the first direction L1.

[0098] The photovoltaic module also has the same or similar beneficial effects as any of the aforementioned electrode structures. The relevant parts can be referenced with each other. In order to avoid repetition, they will not be described here.

[0099] It should be noted that any photovoltaic module, any electrode structure of the aforementioned back-contact solar cell, and any of the aforementioned back-contact solar cells have the same or similar beneficial effects, and the relevant or similar points can be referenced with each other. In order to avoid repetition, the relevant points will not be repeated.

[0100] It should be noted that, for the sake of simplicity, the method embodiments are described as a series of action combinations, but those skilled in the art should be aware that the embodiments of the present application are not limited by the order of the actions described, because according to the embodiments of the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily required by the embodiments of the present application.

[0101] It should be noted that, in this document, the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus comprising a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus comprising the element.

[0102] The embodiments of the present application are described above in conjunction with the accompanying drawings, but the present application is not limited to the above-mentioned specific implementation methods. The above-mentioned specific implementation methods are merely illustrative and not restrictive. Under the guidance of this application, ordinary technicians in this field can also make many forms without departing from the purpose of this application and the scope of protection of the claims, all of which are protected by this application.

Claims

1. An electrode structure of a back contact solar cell, characterized in that: include: An edge first electrode disk is located at one side of the edge of the back contact solar cell body; An edge first busbar line is located between the edge of the back contact solar cell body and the edge first electrode disk, and is electrically connected to the edge first electrode disk; The first collector grid lines and the second collector grid lines are arranged alternately along a first direction and both extend along a second direction; the first direction is different from the second direction; A first bonding wire extends along the first direction and is electrically connected only to the first electrode plate at the edge and the first collector grid line adjacent thereto; The first collector grid line adjacent to the first edge electrode disk includes: the first collector grid line adjacent to the first edge electrode disk in the first direction; and / or the first collector grid line adjacent to the first edge electrode disk includes: the first collector grid line distributed flush with the first edge electrode disk in the first direction; The first bonding wire and the adjacent first collector grid line electrically connected thereto are made of the same material; the first bonding wire and the adjacent first collector grid line electrically connected thereto are an integrated structure.

2. The electrode structure of a back contact solar cell according to claim 1, characterized in that: There is a gap between the adjacent first collector grid line and the adjacent edge first collector grid line; An adjacent second collector grid line that is adjacent to the adjacent first collector grid line in the first direction and away from the edge first electrode disk includes: a first extension section extending from the gap to an area defined by the edge first electrode disk, the edge first collector grid line, the first jumper wire electrically connected to the edge first electrode disk, and the adjacent first collector grid line.

3. The electrode structure of a back contact solar cell according to claim 1, characterized in that: In the first direction, the first bonding wire extends from the edge first electrode plate to which it is electrically connected to all the adjacent first collector grid lines to which it is electrically connected.

4. The electrode structure of a back contact solar cell according to claim 1, characterized in that: In the first direction, the first bonding wire extends from the adjacent first collector grid wire to which it is electrically connected to the interior of the edge first electrode disk to which it is electrically connected.

5. The electrode structure of a back contact solar cell according to claim 4, characterized in that: The number of all first overlap wires electrically connected to one of the edge first electrode disks and one of the adjacent first collector grid lines is greater than or equal to 2; among all the first overlap wires, at least: first overlap wires respectively distributed on both sides of the geometric center of the edge first electrode disk; in the second direction, the distance between the two first overlap wires and the geometric center of the edge first electrode disk is greater than 0.3 mm.

6. The electrode structure of a back contact solar cell according to claim 3, characterized in that: In the first direction, a size of a portion of the first overlap line that exceeds all the adjacent first collector grid lines to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm.

7. The electrode structure of a back contact solar cell according to claim 4, characterized in that: In the first direction, a size of a portion of the first lap line extending to the inside of the edge first electrode disk to which it is electrically connected is greater than 0 and less than or equal to 0.24 mm.

8. The electrode structure of a back contact solar cell according to claim 4, characterized in that: The shape of the first overlap line is: an S shape extending along the first direction; or the shape of the first overlap line is: a Z shape extending along the first direction.

9. The electrode structure of a back contact solar cell according to claim 4, characterized in that: The line width of the first bonding line is greater than or equal to the line width of the adjacent first collector grid line to which it is electrically connected.

10. The electrode structure of a back contact solar cell according to any one of claims 1 to 9, characterized in that: The edge first electrode disk comprises: an edge negative electrode disk; The edge first busbar line includes: an edge cathode busbar line; The first collector grid line includes: a negative electrode collector grid line.

11. The electrode structure of a back contact solar cell according to claim 4, characterized in that: Each of the first bonding wires electrically connected to one of the edge first electrode disks is symmetrical about the geometric center of the edge first electrode disk.

12. The electrode structure of a back contact solar cell according to any one of claims 1 to 9, characterized in that: The edge first electrode plate and the first collector grid line are made of different materials.

13. The electrode structure of a back contact solar cell according to claim 2, characterized in that: The first extending section includes a first portion extending along the first direction and a second portion extending along the second direction.

14. A back contact solar cell, characterized in that: include: A back-contact solar cell body, and an electrode structure of the back-contact solar cell as claimed in any one of claims 1 to 13, located on the back-light side of the back-contact solar cell body.

15. A back contact solar cell, characterized in that: include: a first sub-slice and a second sub-slice; The first sub-sheet comprises: a first sub-back contact solar cell body, and a first electrode structure located on the backlight surface of the first sub-back contact solar cell body; the first electrode structure is the electrode structure of the back contact solar cell according to any one of claims 1 to 13; The second sub-sheet includes: a second sub-back contact solar cell body, and a second electrode structure located on the backlight surface of the second sub-back contact solar cell body; The second electrode structure comprises: an edge second electrode disk, in the first direction, collinear with the edge first electrode disk; An edge electrode frame is located outside the edge second electrode disk and is electrically overlapped with the edge second electrode disk; A second edge busbar line, in the first direction, co-linear with the first edge busbar line; The first collector grid line and the second collector grid line are arranged alternately along the first direction and extend along the second direction; the first direction is different from the second direction; the second collector grid line is aligned and electrically connected to the edge electrode frame; the second collector grid line is aligned and includes: a second collector grid line aligned with the edge electrode frame in the first direction; The second bonding wire extends along the first direction and is electrically connected only to the edge electrode frame and the adjacent second collector grid line; the adjacent second collector grid line includes: the second collector grid line adjacent to the edge electrode frame in the first direction.

16. A photovoltaic module, characterized in that: include: A plurality of back-contact solar cells as claimed in claim 14, and a conductive interconnect electrically connected to the edge first electrode pad.

17. The photovoltaic module according to claim 16, characterized in that: The conductive interconnect extends along the first direction; The first jumper wire and the adjacent first collector grid line electrically connected thereto are an integrated structure. In the second direction, the distance between the two first jumpers and the geometric center of the edge first electrode disk is greater than half of the size of the conductive interconnect in the second direction.

18. A photovoltaic module, characterized in that: include: A plurality of battery strings; the battery strings comprising: a conductive interconnect, and a plurality of first sub-sheets and second sub-sheets as claimed in claim 15; In the battery string, the edge first electrode disk of the first sub-sheet and the edge second electrode disk of the second sub-sheet are connected in series via the conductive interconnector.

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