Solar cell and photovoltaic module

Abstract

The invention relates to a solar cell and a photovoltaic module. The solar cell comprises a cell substrate and an electrode structure located on the cell substrate, the electrode structure comprises a plurality of current collection grid lines, at least one first main joint part, a plurality of first auxiliary joint parts and a first lap line, and the plurality of current collection grid lines comprise first current collection grid lines and second current collection grid lines; the first main connection part is located in the first current collection grid line area and is electrically connected with at least part of first current collection grid lines of the first current collection grid line area, and the plurality of first auxiliary connection parts are located in the second current collection grid line area and are electrically connected with the first current collection grid lines of the second current collection grid line area and are electrically connected with at least part of second current collection grid lines of the second current collection grid line area. Part of the first current collection grid lines of the first current collection grid line area are electrically connected with the first main joint part and the at least one first auxiliary joint part through the first lap line. Therefore, once the electric connection of the main joint part fails, the current can be led out through the auxiliary joint part, and the yield of the solar cell is improved.

Description

Technical Field

[0001] The present application relates to the field of photovoltaic technology, and in particular, to solar cells and photovoltaic modules. Background Art

[0002] In the electrode structure of existing solar cells, a collector grid line discontinuity region is usually provided at the end of the solar cell along the interconnection direction, and some collector grid lines of the same polarity in the collector grid line discontinuity region are electrically connected to the joint part through a lap wire to effectively collect current. However, in the process of preparing solar cells, when the joint parts of the same polarity are electrically connected through conductive interconnects such as welding strips, the joint part electrically connected to some collector grid lines in the collector grid line discontinuity region is prone to failure when the cells are interconnected, resulting in the inability to collect the current of some collector grid lines in the collector grid line discontinuity region, causing a loss of output current, and further resulting in a decrease in the yield of the solar cell.

[0003] Therefore, there is a need to provide improved solar cells and photovoltaic modules to overcome or at least reduce at least some of the disadvantages existing in the above-mentioned prior art. Summary of the invention

[0004] To solve the above technical problems, according to the first aspect of the present application, a solar cell is provided, which includes a cell substrate and an electrode structure, wherein the cell substrate includes a first end and a second end arranged opposite to each other in a first direction and a third end and a fourth end arranged opposite to each other in a second direction, wherein the second direction intersects with the first direction; the electrode structure is located on the cell substrate, and the electrode structure includes a plurality of collector grid lines, at least one first main joint, a plurality of first auxiliary joints and a first overlap line; the plurality of collector grid lines include a first collector grid line and a second collector grid line with opposite polarities and both extending in the first direction, at least part of the first collector grid lines and at least part of the second collector grid lines are alternately distributed in the second direction, and the plurality of collector grid lines located at the third end form a first collector grid line region, and the plurality of collector gate lines located between the third end and the fourth end form a second collector gate line region; the first main joint is located in the first collector gate line region, and is electrically connected to at least part of the first collector gate lines in the first collector gate line region; the plurality of first auxiliary joints are located in the second collector gate line region, wherein part of the first main joints and part of the first auxiliary joints are at least partially colinear in the second direction, and at least one of the first auxiliary joints is electrically connected to one of the first collector gate lines in the second collector gate line region; part of the first collector gate lines in the first collector gate line region are electrically connected to the first main joints through the first jumper wire, and part of the first collector gate lines in the first collector gate line region are electrically connected to at least one of the first auxiliary joints through the first jumper wire.

[0005] Optionally, the first collector gate line region is a collector gate line discontinuous region, and the second collector gate line region is a collector gate line continuous region.

[0006] Optionally, the first main joint is located at the first end and is electrically connected to the first collector gate line in the collector gate line discontinuity zone at the first end; the multiple first auxiliary joints are located at the first end, and the first auxiliary joint at the first end is electrically connected to the first collector gate line in the collector gate line continuous zone at the first end; the first jumper wire is located at the first end, the first collector gate line in the collector gate line discontinuity zone is electrically connected to the first main joint at the first end through the first jumper wire, and the first collector gate line in the collector gate line discontinuity zone is electrically connected to at least one of the first auxiliary joints at the first end through the first jumper wire.

[0007] Optionally, the electrode structure also includes at least one second main joint, a plurality of second auxiliary joints and a second overlap line, wherein the second main joint is located in the collector gate line discontinuity region and is electrically connected to at least part of the second collector gate lines in the collector gate line discontinuity region; the plurality of second auxiliary joints are located in the collector gate line continuous region, wherein part of the second main joints and part of the second auxiliary joints are at least partially colinear in the second direction, and at least one second auxiliary joint is electrically connected to one of the second collector gate lines in the collector gate line continuous region; part of the second collector gate lines in the collector gate line discontinuity region are electrically connected to the second main joint through the second overlap line, and part of the second collector gate lines in the collector gate line discontinuity region are electrically connected to at least one of the second auxiliary joints through the second overlap line.

[0008] Optionally, the second main joint is located at the second end and is electrically connected to the second collector gate line in the collector gate line discontinuity area at the second end, the multiple second auxiliary joints are located at the second end, and the second auxiliary joints at the second end are electrically connected to the second collector gate line in the collector gate line continuous area at the second end, the second jumper is located at the second end, the second collector gate line in the collector gate line discontinuity area is electrically connected to the second main joint at the second end through the second jumper, and the second collector gate line in the collector gate line discontinuity area is electrically connected to at least one of the second auxiliary joints at the second end through the second jumper.

[0009] Optionally, a distance between an end of the first jumper wire at the first end away from the third end and the first collector grid line adjacent to the edge of the third end is different from a distance between an end of the second jumper wire at the second end away from the third end and the second collector grid line adjacent to the edge of the third end.

[0010] Optionally, a projection of the first main joining portion at the first end portion on a plane perpendicular to the first direction at least partially overlaps with a projection of the second main joining portion at the second end portion on the plane perpendicular to the first direction.

[0011] Optionally, the multiple collector gate lines located at the fourth end form another collector gate line discontinuity region, and the electrode structure also includes a first parallel overlap line and at least one first parallel main joint located in the other collector gate line discontinuity region, wherein a portion of the first collector gate lines in the other collector gate line discontinuity region is electrically connected to the first parallel main joint through the first parallel overlap line, a portion of the first collector gate lines in the other collector gate line discontinuity region is electrically connected to at least one first auxiliary joint through the first parallel overlap line, and a distance from one end of the first overlap line located at the third end away from the third end to the first collector gate line adjacent to the edge of the third end is the same as a distance from one end of the first parallel overlap line located at the fourth end away from the fourth end to the first collector gate line adjacent to the edge of the fourth end.

[0012] Optionally, in the first direction, the number of intermittent second collector grid lines interrupted by the first main joint located at the first end is the same as the number of intermittent first collector grid lines interrupted by the second main joint located at the second end, and the intermittent second collector grid lines interrupted by the first main joint and the intermittent first collector grid lines interrupted by the second main joint are alternately distributed along the second direction.

[0013] Optionally, the number of the first auxiliary joints electrically connected to the first main joint does not exceed 3; and / or the number of the second auxiliary joints electrically connected to the second main joint does not exceed 3; and / or the number of the first auxiliary joints electrically connected to the first parallel main joint does not exceed 3.

[0014] Optionally, the distance between the first main joint adjacent to the first auxiliary joint and the first collector grid line adjacent to the third end edge is greater than the distance between the first main joint adjacent to the first auxiliary joint and the first auxiliary joint adjacent to the first main joint; and / or the distance between the second main joint adjacent to the second auxiliary joint and the second collector grid line adjacent to the third end edge is greater than the distance between the second main joint adjacent to the second auxiliary joint and the second auxiliary joint adjacent to the second main joint; and / or the distance between the first parallel main joint adjacent to the first auxiliary joint and the first collector grid line adjacent to the fourth end edge is greater than the distance between the first parallel main joint adjacent to the first auxiliary joint and the first auxiliary joint adjacent to the first parallel main joint.

[0015] Optionally, the width of the first overlap line, and / or the second overlap line, and / or the first parallel overlap line in the first direction along the second direction first increases and then decreases, the first overlap line is widest at the position electrically connected to the first main joint, the second overlap line is widest at the position electrically connected to the second main joint, and the first parallel overlap line is widest at the position electrically connected to the first parallel main joint, and the first overlap line or the second overlap line or the first parallel overlap line have different degrees of width gradient from the widest point toward the direction of decreasing width.

[0016] Optionally, the first collector gate line adjacent to the third end edge in the collector gate line discontinuity region is continuous.

[0017] Optionally, in the collector gate line continuous region, the length of at least one of the second collector gate lines adjacent to the first main junction is shorter than the lengths of the remaining second collector gate lines.

[0018] Optionally, in the collector gate line continuous region, at least one second collector gate line having a length smaller than that of the remaining second gate lines and adjacent to the first main junction is electrically connected to the second auxiliary junction.

[0019] Optionally, the solar cell further includes a doped semiconductor layer, wherein the doped semiconductor layer is disposed between the electrode structure and the cell substrate and is electrically connected to the electrode structure.

[0020] According to a second aspect of the present application, a photovoltaic module is provided. The photovoltaic module includes at least two aforementioned solar cells.

[0021] According to the technical solution of the present application, the corresponding main joint part is interconnected with at least one auxiliary joint part by utilizing the overlap wire, so that the collector grid line located at the end of the interconnection direction can form a good interconnection with at least one of the corresponding main joint part and the auxiliary joint part with the minimum number of interrupted collector grid lines. Therefore, once the electrical connection of the main joint part fails, the current can still be extracted through the auxiliary joint part, which not only improves the connection reliability, but also enables the same-sex current in the discontinuity area of ​​the collector grid line to be effectively collected, thereby improving the current collection efficiency and avoiding the loss of output current, which is ultimately beneficial to improving the yield of solar cells.

[0022] Based on the detailed description of the specific embodiments of the present application in combination with the accompanying drawings below, those skilled in the art will become more aware of the above and other objects, advantages and features of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Features, advantages and exemplary embodiments of the present application will be described below with reference to the accompanying drawings, in which like reference numerals indicate like elements, and in which:

[0024] Figure 1 A schematic plan view of a solar cell according to an embodiment of the present application;

[0025] Figure 2 A partial schematic diagram showing a first main joint portion and a first auxiliary joint portion located at a first end portion of a solar cell according to an embodiment of the present application and an electrode structure adjacent thereto;

[0026] Figure 3 A partial schematic diagram showing a second main joint portion and a second auxiliary joint portion located at a second end portion of a solar cell according to an embodiment of the present application and an electrode structure adjacent thereto;

[0027] Figure 4 A partial schematic diagram showing a first auxiliary joint portion and a first parallel main joint portion located at a first end portion of a solar cell according to an embodiment of the present application and an electrode structure adjacent thereto; and

[0028] Figure 5 It is a partial schematic diagram showing a second auxiliary joint portion and a second parallel main joint portion located at a second end portion of a solar cell according to an embodiment of the present application and an adjacent electrode structure. DETAILED DESCRIPTION

[0029] The exemplary embodiments of the present application will be described in more detail below in conjunction with the accompanying drawings. The description of the exemplary embodiments is merely exemplary and is by no means a limitation of the present application and its application or usage. Moreover, the sizes and proportions of the components in the drawings are merely schematic and do not strictly correspond to actual products.

[0030] In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0031] The solar cell and photovoltaic module provided in the embodiments of the present application are described in detail below through specific embodiments in conjunction with the accompanying drawings.

[0032] The present application provides a solar cell 100 . Figure 1 FIG. 1 is a schematic plan view of a solar cell 100 according to an embodiment of the present application. Figure 2 A partial schematic diagram showing a first main joint portion P1 and a first auxiliary joint portion P2 at a first end portion E1 of a solar cell 100 and their adjacent electrode structures is shown, wherein the middle section at the natural fracture line of the solar cell 100 is not shown. Figure 3 A partial schematic diagram showing a second main joint portion N1 and a second auxiliary joint portion N2 located at a second end portion E2 of a solar cell 100 according to an embodiment of the present application and their adjacent electrode structures, wherein the middle section at the natural fracture line of the solar cell 100 is not shown. Figure 4 A partial schematic diagram showing a first auxiliary joint portion P2 and a first parallel main joint portion P3 and adjacent electrode structures located at a first end portion E1 of a solar cell 100 according to an embodiment of the present application, wherein the middle section at the natural fracture line of the solar cell 100 is not shown. Figure 5 The schematic diagram is a partial diagram showing the second auxiliary joint portion N2 and the second parallel main joint portion N3 at the second end portion E2 of the solar cell 100 according to an embodiment of the present application and the electrode structure adjacent thereto, wherein the middle section at the natural fracture line of the solar cell 100 is not shown. It should be noted that the "end" mentioned herein does not refer to the edge of the corresponding component or region, but refers to the region within a distance range from the corresponding edge.

[0033] like Figure 1As shown, the solar cell 100 includes a cell substrate 10 and an electrode region A located on the cell substrate 10, wherein the cell substrate 10 is used to generate current. In this embodiment, the solar cell 100 may be a back-contact solar cell, and the surface where the electrode region A is located is the backlight surface of the cell substrate 10. The cell substrate 10 includes a first end E1 and a second end E2 arranged oppositely in a first direction D1, and a third end E3 and a fourth end E4 arranged oppositely in a second direction D2, wherein the first direction D1 intersects the second direction D2. Specifically, as Figure 1 As shown, in this embodiment, the first direction D1 is perpendicular to the second direction D2. For the convenience of description, the direction from the first end E1 to the second end E2 is defined as the positive direction of the first direction D1, and the direction from the fourth end E4 to the third end E3 is defined as the positive direction of the second direction D2.

[0034] like Figures 1 to 5 As shown, the solar cell 100 also includes an electrode structure, which is located on the battery substrate 10, specifically, in the area corresponding to the electrode area A, for collecting and conducting the current generated by the battery substrate 10. The electrode structure includes a plurality of collector grid lines, at least one first main joint, a plurality of first auxiliary joints and a first overlap line. The plurality of collector grid lines include a first collector grid line and a second collector grid line with opposite polarities, both extending in the first direction, at least part of the first collector grid line and at least part of the second collector grid line are alternately distributed in the second direction, the plurality of collector grid lines located at the third end form a first collector grid line area, and the plurality of collector grid lines located between the third end and the fourth end form a second collector grid line area. The first main joint is located in the first collector grid line area and is electrically connected to at least part of the first collector grid line in the first collector grid line area. The plurality of first auxiliary joints are located in the second collector grid line area, wherein part of the first main joint and part of the first auxiliary joint are at least partially collinear in the second direction, and at least one first auxiliary joint is electrically connected to a first collector grid line in the second collector grid line area. Part of the first collector gate line in the first collector gate line region is electrically connected to the first main joint portion through the first bonding line, and part of the first collector gate line in the first collector gate line region is electrically connected to at least one first auxiliary joint portion through the first bonding line.

[0035] In the present application, the first main joint is interconnected with at least one first auxiliary joint by utilizing the first overlap wire, so that the collector grid line located at the end of the interconnection direction can form a good interconnection with at least one of the first main joint and the first auxiliary joint with as few interruptions as possible. Therefore, once the electrical connection of the first main joint fails, the current can still be extracted through the first auxiliary joint, which not only improves the connection reliability, but also enables the same-sex current in the first collector grid line area to be effectively collected, thereby improving the current collection efficiency and avoiding the loss of output current, which is ultimately beneficial to improving the yield of solar cells.

[0036] It should be understood that in other embodiments not shown in the application, the first main joint portion may also be electrically connected to two or more first auxiliary joint portions. Optionally, the number of first auxiliary joint portions electrically connected to the first main joint portion does not exceed 3 to avoid increasing the path of current transmission and thus increasing the loss of current collection.

[0037] It should be noted that the first collector gate line region, the second collector gate line region and the third collector gate line region to be described in detail later can all be continuous collector gate line regions. At this time, the electrical insulation between the first overlap line and the second collector gate line can be achieved by an insulating material arranged between the two, and the electrical insulation between the first parallel overlap line and the second collector gate line to be described in detail later can be achieved by an insulating material arranged between the two, that is, the second collector gate line of the first collector gate line region, the second collector gate line region and the third collector gate line region is still continuous.

[0038] It should be understood that the electrical insulation between the first bonding wire, the first parallel bonding wire and the second collector grid wire can also be achieved by disconnecting the second collector grid wire. Specifically, Figures 2 to 5 As shown, the first collector gate line region can be a collector gate line discontinuous region, and the second collector gate line region can be a collector gate line continuous region. Figures 2 to 5 The specific structure of the electrode structure of one embodiment of the present application is described in more detail.

[0039] like Figure 2 As shown, the electrode structure includes a plurality of collector grid lines, the plurality of collector grid lines include a first collector grid line 211 and a second collector grid line 212 with opposite polarities and extending in a first direction D1, at least part of the first collector grid line 211 and at least part of the second collector grid line 212 are alternately distributed in a second direction D2, a plurality of collector grid lines located at the third end E3 form a collector grid line discontinuous area, and a plurality of collector grid lines located between the third end E3 and the fourth end E4 form a collector grid line continuous area, wherein the plurality of collector grid lines are used to collect the current generated in the battery substrate. Specifically, as Figures 2 to 5As shown, the first collector gate lines 211 and the second collector gate lines 212 are alternately and equidistantly distributed in the second direction D2, wherein the distance between two adjacent first collector gate lines 211 and the distance between two adjacent second collector gate lines 212 are both d.

[0040] It should be noted that, for the sake of clarity, in the present embodiment, the first collector grid lines 211 are all drawn with solid lines, and the second collector grid lines 212 are all drawn with dotted lines. The solid lines and the dotted lines are not used to indicate the actual shapes and actual thicknesses of the first collector grid lines 211 and the second collector grid lines 212. In addition, the first collector grid lines 211 and the second collector grid lines 212 have opposite polarities, indicating that: the first collector grid line 211 is a positive collector grid line, and the second collector grid line 212 is a negative collector grid line; or the first collector grid line 211 is a negative collector grid line, and the second collector grid line 212 is a positive collector grid line. In the collector gate line continuous area, most of the first collector gate line 211 and the second collector gate line 212 extend to the edges of the electrode area A at the first end E1 and the second end E2, and the first collector gate line 211 and the second collector gate line 212 are not interrupted by the first auxiliary joint or the second auxiliary joint to be described in detail later; while in the collector gate line discontinuity area, the first collector gate line 211 and the second collector gate line 212 are both interrupted, specifically, the first collector gate line 211 is interrupted by at least one second main joint to be described in detail later, and the second collector gate line 212 is interrupted by at least one first main joint to be described in detail later.

[0041] The electrode structure further includes at least one first main joint portion, which is located in the collector grid line discontinuity region and is electrically connected to at least part of the first collector grid line 211 in the collector grid line discontinuity region. Figure 2In the local area shown, the electrode structure is provided with a first main joint P1, and the first main joint P1 is a joint closest to the third end E3 among all the joints adjacent to the first end E1. It should be noted that in other embodiments not shown in the present application, the portion at the first end E1 of the electrode structure may also be provided with two or more first main joints P1 to achieve effective collection of current. It should be understood that a first main joint may also be provided in the middle section of the electrode structure not shown in the present application to achieve effective collection of current in the middle section. The first main joint may be directly electrically connected to at least part of the first collector grid line 211 in the collector grid line discontinuity zone, or may be electrically connected to at least part of the first collector grid line 211 in the collector grid line discontinuity zone by means of a first overlap wire to be described in detail later, so that the current collected by at least part of the first collector grid line 211 in the collector grid line discontinuity zone may be collected to the first main joint. It should be noted that the collector grid lines electrically connected to the first main joint are all first collector grid lines 211, that is, the collector grid lines electrically connected to the first main joint are all same-sex collector grid lines, and the first main joint and the first overlap line are separated from the opposite-sex second collector grid lines 212 by a certain distance, so that there is no connection with the second collector grid line 212, thereby avoiding short circuit.

[0042] The electrode structure further includes a plurality of first auxiliary joints, the plurality of first auxiliary joints are located in the collector grid line continuous region, part of the first main joints and part of the first auxiliary joints are at least partially collinear in the second direction D2, and at least one first auxiliary joint is electrically connected to a first collector grid line 211 in the collector grid line continuous region. Specifically, Figure 2In the local area shown, the first auxiliary joint P2 is a joint adjacent to the first end E1 in the collector grid line continuous area. The first collector grid line 211 in the collector grid line continuous area is shown as a continuous area first collector grid line 2113, wherein each continuous area first collector grid line 2113 is directly electrically connected to a first auxiliary joint P2 at the first end E1. It should be understood that in the middle section of the electrode structure not shown in the present application, each continuous area first collector grid line 2113 can also be electrically connected to at least one first auxiliary joint provided in the middle section to achieve effective collection of current in the middle section. It should be noted that part of the first main joint and part of the first auxiliary joint are at least partially colinear in the second direction D2, indicating that part of the first main joint and part of the first auxiliary joint arranged in a row in the second direction D2 can be connected in series by a welding strip extending along the second direction D2, thereby collecting the current on the same-sex joint. Specifically, in this embodiment, the length of the first main joint in the first direction D1 can be the same as the length of the first auxiliary joint in the first direction D1, so as to facilitate the convenience of operation during the welding process of the welding strip. It should be understood that in other embodiments not shown in the present application, the length of the first main joint in the first direction D1 can also be greater than the length of the first auxiliary joint in the first direction D1. In addition, the length of the first main joint in the second direction D2 is slightly greater than the spacing d of the adjacent first collector grid lines 211 in the second direction D2, and the length of the first auxiliary joint in the second direction D2 is significantly less than half of the spacing d. Designed in this way, the layout of the collector grid lines is more compact, which is conducive to the effective collection of current. Optionally, the thickness of the first main joint in the direction perpendicular to the plane where the first direction D1 and the second direction D2 are located is the same as the thickness of the first auxiliary joint in the direction perpendicular to the plane where the first direction D1 and the second direction D2 are located, so that during the welding process of the welding strip, the welding strip can be welded on the same plane, which improves the convenience and operability of the welding process.

[0043] Optionally, the first main joining portion and the first auxiliary joining portion may be joining portions of similar shapes formed by the same process and the same material.

[0044] like Figures 2 to 5 As shown, the electrode structure also includes a first overlap wire, and part of the first collector grid line 211 in the collector grid line discontinuity area is electrically connected to the first main joint through the first overlap wire, and part of the first collector grid line 211 in the collector grid line discontinuity area is electrically connected to at least one first auxiliary joint through the first overlap wire. In this embodiment, the overlap wire is used to collect the current collected by the collector grid line, and generally extends in the second direction D2. Similarly, it should be understood that a first overlap wire may also be provided in the middle section of the electrode structure not shown in the present application to collect the current collected by the first collector grid line 211 in the middle section.

[0045] Optionally, the distance between the first main joint portion adjacent to the first auxiliary joint portion and the first collector grid line adjacent to the third end edge is greater than the distance between the first main joint portion adjacent to the first auxiliary joint portion and the first auxiliary joint portion adjacent to the first main joint portion. The width of the first overlap line in the first direction D1 along the second direction D2 first increases and then decreases, and the first overlap line has different degrees of gradual width change from the widest point to the direction of decreasing width. Exemplarily, the widths at the two ends along the second direction D2 are substantially the same, and the first overlap line is widest at the position electrically connected to the first main joint portion.

[0046] exist Figure 2 In the local area shown, the collector grid line continuous area located at the first end E1 is shown as L1, and the collector grid line continuous area L1 refers to the area L1 surrounded by a single-point dashed line and a natural break line. In the collector grid line continuous area L1 located at the first end E1, a plurality of first auxiliary joints P2 are provided, and most of the first collector grid line 211 and the second collector grid line 212 extend to the edge of the electrode area A at the first end E1; Figure 2 In the local area shown, the collector gate line discontinuity area located at the first end E1 is shown as M1, and the collector gate line discontinuity area M1 refers to the area M1 surrounded by a single-point dashed line and a natural break line at the first end E1. In the collector gate line discontinuity area M1 located at the first end E1, a first main joint P1 is provided, and the second collector gate line 212 does not extend to the edge of the electrode area A at the first end E1 like the first collector gate line 211, that is, there is a discontinuity between the second collector gate line 212 and the edge of the electrode area A at the first end E1.

[0047] like Figure 2As shown, the first main joint P1 is located at the first end E1 and is electrically connected to the first collector gate line 211 of the collector gate line discontinuity area M1 located at the first end E1, a plurality of first auxiliary joints P2 are located at the first end E1, and the first auxiliary joint P2 located at the first end E1 is electrically connected to the first collector gate line 211 of the collector gate line continuous area L1 located at the first end E1, the first jumper 22 is located at the first end E1, the first collector gate line 211 of the collector gate line discontinuity area M1 is electrically connected to the first main joint P1 at the first end E1 through the first jumper 22, and the first collector gate line 211 of the collector gate line discontinuity area M1 is electrically connected to at least one first auxiliary joint P2 at the first end E1 through the first jumper 22. It should be noted that, when the first jumper wire 22 does not electrically connect the first main joint P1 with the first auxiliary joint P2, the first collector grid line located at the first end E1 can only be electrically connected to the first main joint through the first jumper wire. Once the welding of the first main joint fails, the current located in the fine grid interruption area near the first end E1 will not be able to be collected and exported, and the risk of the current not being collected and exported is high. However, by adopting the technical solution of the present application, once the electrical connection of the first main joint fails, the first jumper wire can also be used to export the current through the first auxiliary joint, which significantly improves the current collection efficiency and yield of the photovoltaic module.

[0048] Specifically, in Figure 2 In the local area shown, the first main joint P1 is a joint that is closest to the third end E3 among all the joints adjacent to the first end E1. It should be noted that in other embodiments not shown in the present application, the electrode structure may also be provided with two or more first main joints P1 to achieve effective collection of current. The first main joint P1 can be directly electrically connected to part of the first collector grid line 211 in the collector grid line discontinuity area, or electrically connected to part of the first collector grid line 211 in the collector grid line discontinuity area by means of the first jumper wire 22, so that the current collected by the first collector grid line 211 in the collector grid line discontinuity area M1 located at the first end E1 can be collected to the first main joint P1. It should be noted that the collector grid lines electrically connected to the first main joint P1 are all first collector grid lines 211, that is, the collector grid lines electrically connected to the first main joint P1 are all same-sex collector grid lines, and the first main joint P1 and the first overlap line 22 are separated from the second opposite-sex collector grid lines 212 by a certain distance, so that there is no connection with the second collector grid line 212, thereby avoiding short circuit.

[0049] exist Figure 2In the local area shown, the first auxiliary joint P2 is a joint adjacent to the first end E1 in the collector gate line continuous area L1 located at the first end E1. The first collector gate line 211 in the collector gate line continuous area L1 located at the first end E1 is shown as a continuous area first collector gate line 2113, wherein each continuous area first collector gate line 2113 is provided with a first auxiliary joint P2 at the first end E1, and one continuous area first collector gate line 2113 is directly electrically connected to one first auxiliary joint P2.

[0050] exist Figure 2 In the local area shown, the first lap line 22 is arranged at the edge of the electrode region A at the first end E1 and extends substantially in the second direction D2. In addition, the first collector grid line 211 in the collector grid line discontinuity region M1 at the first end E1 is divided into a first lap line collector grid line 2111 and a first main joint collector grid line 2112, wherein the first lap line collector grid line 2111 is directly electrically connected to the first lap line 22 at the first end E1 and at the edge of the electrode region A, and the first main joint collector grid line 2112 is directly electrically connected to the first main joint P1 at the first end E1.

[0051] Specifically, in Figure 2 In the local area shown, the length of the first main joint P1 in the first direction D1 can be the same as the length of the first auxiliary joint P2 in the first direction D1, and the length of the first main joint P1 in the second direction D2 is slightly larger than the spacing d between adjacent first collector grid lines 211 in the second direction D2, and the first main joint collector grid lines 2112 are electrically connected to the first main joint P1 at both ends of the first main joint P1 in the second direction D2, so that the current collected by the first main joint collector grid lines 2112 can be directly collected to the first main joint P1.

[0052] The first lap wire 22 can be electrically connected to the first main joint P1 via a first collector grid line 2112a disposed between the first lap wire 22 and the first main joint P1. Optionally, the first lap wire 22 can also be electrically connected to the first main joint P1 via a first connection line 23 disposed between the first lap wire 22 and the first main joint P1, wherein the first collector grid line 2112a and the first connection line 23 are stacked on a plane perpendicular to the first direction D1 and the second direction D2, and the width of the first connection line 23 is greater than the width of the first collector grid line 211 to increase the reliability of current transmission. Arranged in this way, not only can the currents collected by the first lap wire collector grid line 2111 and the first main joint collector grid line 2112 in the collector grid line discontinuity area M1 at the first end E1 be directly collected to the first main joint P1, but also it is conducive to reducing the difficulty of overlapping the first connection line 23 with the first main joint P1, and improving the fault tolerance rate in the electrode structure preparation process. In addition, by providing the first connecting wire 23, the stress in the edge area of ​​the solar cell is made more uniform, which is beneficial to reduce the probability of the solar cell breaking. It should be noted that the larger the width of the first connecting wire 23, the smaller the resistance when transmitting current, which is more conducive to the transmission of current. In this embodiment, the number of the first connecting wire 23 is one. In other embodiments, the number of the first connecting wire 23 is not limited to this.

[0053] In this embodiment, if Figure 2 As shown, in the second direction D2, in the area between the first main joint P1 and the first bonding line 22, a first main joint collector grid line 2112 is provided on both the upper and lower sides of the first connection line 23, and the first main joint collector grid line 2112 is electrically connected to the first bonding line 22 at the end adjacent to the first end edge, and is electrically connected to the first main joint P1 at the other end. In this way, on the one hand, the reliability of the current transmission collected by the first bonding line 22 is increased, and on the other hand, the current in the area between the first main joint P1 and the first bonding line 22 is fully collected.

[0054] Optionally, in some embodiments, the first jumper wire 22 can be integrally formed with the first collector grid line 211 directly electrically connected to the first jumper wire 22, and the integrally formed here may mean that the two are printed together. In this case, the first jumper wire 22 and the first collector grid line 211 are made of the same material. The two are integrally formed, which is convenient for processing and has high production efficiency. It can also avoid the problem that the first jumper wire 22 and the first collector grid line 211 cannot form an effective electrical connection due to processing errors caused by forming the first jumper wire 22 and the first collector grid line 211 in batches, thereby ensuring a reliable connection between the first jumper wire 22 and the first collector grid line 211 directly electrically connected to the first jumper wire 22.

[0055] In addition, in some embodiments, the first lap wire 22 may also be integrally formed with the first end connection wire 23. The method of integrally forming and its beneficial effects are described above and will not be repeated here.

[0056] like Figure 2 As shown, the first main joint P1 electrically connected to part of the first collector grid line 211 in the collector grid line discontinuity region is also electrically connected to at least one first auxiliary joint P2 through the first bridging line 22. In this embodiment, the number of the first main joint P1 and the first auxiliary joint P2 electrically connected to the first bridging line 22 is the same. Specifically, Figure 2 As shown, a first main joint P1 is electrically connected to a first auxiliary joint P2 through a first overlap wire 22. Arranged in this way, the first main joint P1 and the first auxiliary joint P2 can form a good interconnection with the least possible interruption of the collector grid lines between the first end and the second end, which not only improves the connection reliability, but also enables the same-sex current in the collector grid line discontinuity area M1 located at the first end E1 to be effectively collected, thereby improving the current collection efficiency and avoiding the loss of output current, which is ultimately beneficial to improving the yield of the solar cell. It should be understood that in other embodiments not shown in the application, the first main joint P1 located at the first end E1 can also be electrically connected to two or more first auxiliary joints P2 located at the first end E1.

[0057] In addition, in this embodiment, the first collector grid line 211 and the second collector grid line 212 both extend in the first direction D1, that is, the first collector grid line 211 and the second collector grid line 212 are each not provided with a bending section. In this way, the problem of easy wire breakage at the bending section when the collector grid line is printed is avoided, which is ultimately beneficial to improving the yield of the solar cell.

[0058] In the embodiment of the present application, the electrode structure further includes at least one second main joint portion, which is located in the collector grid line discontinuity region and is electrically connected to at least part of the second collector grid line in the collector grid line discontinuity region. Figure 3In the local area shown, the electrode structure is provided with a second main joint N1, which is a joint closest to the third end E3 among all the joints adjacent to the second end E2. It should be noted that in other embodiments not shown in the present application, the portion at the second end E2 of the electrode structure may also be provided with two or more second main joints N1 to achieve effective collection of current. It should be understood that a second main joint may also be provided in the middle section of the electrode structure not shown in the present application to achieve effective collection of current in the middle section. The second main joint N1 may be directly electrically connected to at least part of the second collector grid line 212 in the collector grid line discontinuity zone, or may be electrically connected to at least part of the second collector grid line 212 in the collector grid line discontinuity zone by means of a second jumper wire 24 to be described in detail later, so that the current collected by at least part of the second collector grid line 212 in the collector grid line discontinuity zone may be collected to the second main joint N1. It should be noted that the collector grid lines electrically connected to the second main joint N1 are all second collector grid lines 212, that is, the collector grid lines electrically connected to the second main joint N1 are all same-sex collector grid lines, and the second main joint N1 and the second jumper wire 24 are separated from the first opposite-sex collector grid line 211 by a certain distance, so that there is no connection with the first collector grid line 211, thereby avoiding short circuit.

[0059] The electrode structure further includes a plurality of second auxiliary joints, which are located in the collector grid line continuous region, wherein part of the second main joints and part of the second auxiliary joints are at least partially collinear in the second direction, and at least one second auxiliary joint is electrically connected to a second collector grid line in the collector grid line continuous region. Figure 3 In the local area embodiment shown, the second auxiliary joint N2 is a joint adjacent to the second end E2 in the collector grid line continuous area. The second collector grid line 212 in the collector grid line continuous area is shown as a continuous area second collector grid line 2123, wherein each continuous area second collector grid line 2123 is directly electrically connected to a second auxiliary joint N2 at the second end E2. It should be understood that in the middle section of the electrode structure not shown in the present application, each continuous area second collector grid line 2123 can also be electrically connected to at least one second auxiliary joint provided in the middle section to achieve effective collection of current in the middle section. It should be noted that part of the second main joint and part of the second auxiliary joint are at least partially colinear in the second direction D2, indicating that part of the second main joint and part of the second auxiliary joint arranged in a row in the second direction D2 can be connected in series by a welding strip extending along the second direction D2, thereby collecting the current on the same-sex joint.

[0060] In the embodiment of the present application, the shapes and sizes of the second main joining portion and the second auxiliary joining portion are similar to those of the first main joining portion and the first auxiliary joining portion, and are not described again for the sake of brevity.

[0061] like Figure 3 As shown, the electrode structure also includes a second lap wire, and part of the second collector grid line 212 in the collector grid line discontinuity area is electrically connected to the second main joint through the second lap wire, and part of the second collector grid line 212 in the collector grid line discontinuity area is electrically connected to at least one second auxiliary joint through the second lap wire. Similarly, the second lap wire is used to collect the current collected by the collector grid line, and generally extends in the second direction D2. It should be understood that a second lap wire may also be provided in the middle section of the electrode structure not shown in the present application to collect the current collected by the second collector grid line 212 in the middle section. In the present application, by using the second lap wire to interconnect the second main joint with at least one second auxiliary joint, the second main joint and the second auxiliary joint can be well interconnected with each other with as few collector grid lines interrupted as possible between the first end and the second end, which not only improves the connection reliability, but also enables the same-sex current in the collector grid line discontinuity area to be effectively collected, thereby improving the current collection efficiency and avoiding the loss of output current, which is ultimately beneficial to improving the yield of the solar cell. It should be understood that in other embodiments not shown in the application, the second main joint portion may also be electrically connected to two or more second auxiliary joint portions. Optionally, the number of second auxiliary joint portions electrically connected to the second main joint portion does not exceed 3 to avoid increasing the path of current transmission and thus increasing the loss of current collection.

[0062] exist Figure 3 In the local area shown, the collector grid line continuous area located at the second end E2 is shown as L2, and the collector grid line continuous area L2 refers to the area L2 surrounded by a single-point dashed line and a natural break line. In the collector grid line continuous area L2 located at the second end E2, a plurality of second auxiliary joints N2 are provided, and most of the first collector grid lines 211 and the second collector grid lines 212 extend to the edge of the electrode area A at the second end E2; Figure 3 In the local area shown, the collector grid line discontinuity area at the second end E2 is shown as M2, which refers to the area M2 surrounded by a single-point dash line and a natural break line at the second end E2. In the collector grid line discontinuity area M2 at the second end E2, a second main joint N1 is provided, and the first collector grid line 211 does not extend to the edge of the electrode area A at the second end E2 like the second collector grid line 212, that is, there is a discontinuity between the first collector grid line 211 and the edge of the electrode area A at the second end E2. In this way, opposite electrodes are provided at both ends of the solar cell along the extension direction of the collector grid line, and the electrodes at both ends of the solar cell have good correspondence, which not only avoids the personalized design of the solar cell, but also reduces the difficulty of interconnection between solar cells.

[0063] like Figure 3 As shown, the second main joint portion N1 is disposed at the second end portion E2 and is electrically connected to the second collector gate line 212 located in the collector gate line discontinuity region M2 at the second end portion E2. Figure 3 In the illustrated embodiment, the electrode structure is provided with a second main joint N1, which is a joint closest to the third end E3 among all the joints adjacent to the second end E2. It should be noted that in other embodiments not shown in the present application, the electrode structure may also be provided with two or more second main joints N1 to achieve effective collection of current. The second main joint N1 may be directly electrically connected to part of the second collector grid line 212 in the collector grid line discontinuity region, or may be electrically connected to part of the second collector grid line 212 in the collector grid line discontinuity region by means of a second jumper wire 24 to be described in detail later, so that the current collected by the second collector grid line 212 in the collector grid line discontinuity region M2 located at the second end E2 may be collected to the second main joint N1. It should be noted that the collector grid lines electrically connected to the second main joint N1 are all second collector grid lines 212, that is, the collector grid lines electrically connected to the second main joint N1 are all same-sex collector grid lines, and the second main joint N1 and the second jumper wire 24 are separated from the first opposite-sex collector grid line 211 by a certain distance, so that there is no connection with the first collector grid line 211, thereby avoiding short circuit.

[0064] exist Figure 3 In the local area shown, a plurality of second auxiliary joints N2 are located at the second end E2, and the second auxiliary joint N2 located at the second end E2 is electrically connected to the second collector grid line 212 of the collector grid line continuous area L2 located at the second end E2. Specifically, the second auxiliary joint N2 is a joint adjacent to the second end E2 in the collector grid line continuous area L2 located at the second end E2. The second collector grid line 212 in the collector grid line continuous area L2 located at the second end E2 is shown as a continuous area second collector grid line 2123, wherein each continuous area second collector grid line 2123 is provided with a second auxiliary joint N2 at the second end E2, and a continuous area second collector grid line 2123 is directly electrically connected to a second auxiliary joint N2.

[0065] exist Figure 3In the area shown, the second jumper wire 24 is located at the second end E2, and the second collector grid line 212 of the collector grid line discontinuity region M2 is electrically connected to the second main joint N1 at the second end E2 through the second jumper wire 24. Specifically, the second jumper wire 24 is arranged at the edge of the electrode region A at the second end E2, and extends substantially in the second direction D2. In addition, the second collector grid line 212 in the collector grid line discontinuity region M2 located at the second end E2 is divided into a second jumper wire collector grid line 2121 and a second main joint portion collector grid line 2122, wherein the second jumper wire collector grid line 2121 is directly electrically connected to the second jumper wire 24 at the second end E2 and at the edge of the electrode region A, and the second main joint portion collector grid line 2122 is directly electrically connected to the second main joint portion N1 at the second end E2.

[0066] The shapes and sizes of the second main joining portion and the second auxiliary joining portion are similar to those of the first main joining portion and the first auxiliary joining portion, and are not described again for the sake of brevity.

[0067] like Figure 3 As shown, in the opposite direction of the first direction D1, the second main joint N1 is electrically connected to only one second main joint collector grid line 2122, so that the current collected by the second main joint collector grid line 2122 can be directly collected to the second main joint N1. The second jumper 24 can be electrically connected to the second main joint N1 through a second main joint collector grid line 2122a arranged between the second jumper 24 and the second main joint N1. Optionally, the second jumper 24 can also be electrically connected to the second main joint N1 via a second connecting line 25 arranged between the second jumper 24 and the second main joint N1. In this way, the currents collected by the second jumper collector grid line 2121 and the second main joint collector grid line 2122 in the collector grid line discontinuity area M2 at the second end E2 can be directly collected to the second main joint N1.

[0068] Similarly, the second bonding wire 24 can be integrally formed with the second collector grid line 212 directly electrically connected to the second bonding wire 24, or the second bonding wire 24 can also be integrally formed with the second connecting wire 25. The manner and beneficial effects of the integral forming can be found in the description of the first bonding wire 22 above, which will not be repeated here. In addition, the shape and arrangement of the second connecting wire 25 can be found in the description of the first connecting wire 23 above, which will not be repeated here for the sake of brevity.

[0069] The arrangement of the electrode structure at the second end E2 is different from that at the first end E1. At the second end E2, in the area between the second main joint N1 and the second jumper line 24, no second collector grid line is set on the upper and lower sides of the second connecting line 25.

[0070] like Figure 3 As shown, the second collector grid line 212 of the collector grid line discontinuity region M2 is electrically connected to at least one second auxiliary joint N2 at the second end E2 through the second jumper 24, that is, the second main joint N1 is also electrically connected to at least one second auxiliary joint N2 through the second jumper 24. In this embodiment, the number of the second main joint N1 and the second auxiliary joint N2 electrically connected to the second jumper 24 is the same. Specifically, as Figure 2 As shown, a second main joint N1 is electrically connected to a second auxiliary joint N2 through a second lap wire 24. It should be understood that in other embodiments not shown in the application, the second main joint N1 may also be electrically connected to two or more second auxiliary joints N2. Arranged in this way, the second main joint N1 can form a good interconnection with the second auxiliary joint N2 while interrupting as few collector grid lines as possible between the first end and the second end, which not only improves the connection reliability, but also enables the same-sex current in the collector grid line discontinuity area M2 located at the second end E2 to be effectively collected; in addition, it can avoid the second lap wire 24 at the second end E2 from interrupting more first collector grid lines 211 due to the need to prevent electrical connection with the first collector grid line 211, thereby achieving effective collection of opposite-sex currents, which is beneficial to reducing the dead zone on the solar cell and reducing the loss of solar cell performance.

[0071] Optionally, the distance between the second main joint part N1 adjacent to the second auxiliary joint part N2 and the second collector grid line 212 adjacent to the third end edge is greater than the distance between the second main joint part N1 adjacent to the second auxiliary joint part N2 and the second auxiliary joint part N2 adjacent to the second main joint part N1. The width of the second lap line 24 in the first direction D1 along the second direction D2 first increases and then decreases, and the width of the second lap line from the widest point to the direction of decreasing width is different. Exemplarily, the widths at the two ends along the second direction D2 are substantially the same, and the second lap line 24 is widest at the position electrically connected to the second main joint part N1.

[0072] As described above, it should be understood that in the middle region between the first end E1 and the second end E2 of the solar cell 100 not shown in the present application, the electrode structure may further include a first middle main joint and a first middle auxiliary joint, wherein part of the first middle main joint and part of the first main joint P1 are at least partially collinear in the first direction D1, and part of the first middle auxiliary joint and part of the first auxiliary joint P2 are at least partially collinear in the first direction D1. The first middle main joint and the first middle auxiliary joint are each electrically connected to part of the first collector grid line 211 in the middle region, so that the current collected by part of the first collector grid line 211 in the middle region can be collected to the first middle main joint and the first middle auxiliary joint.

[0073] In addition, the electrode structure may further include a second intermediate main joint and a second intermediate auxiliary joint, wherein a portion of the second intermediate main joint and a portion of the second main joint N1 are at least partially collinear in the first direction D1, and a portion of the second intermediate auxiliary joint and a portion of the second auxiliary joint N2 are at least partially collinear in the first direction D1. The second intermediate main joint and the second intermediate auxiliary joint are each electrically connected to a portion of the second collector grid line 212 in the middle region, so that the current collected by the portion of the second collector grid line 212 in the middle region can be collected to the second intermediate main joint and the second intermediate auxiliary joint.

[0074] Optionally, the distance between the end of the first lap wire 22 at the first end E1 away from the third end E3 and the first collector grid line 2111 adjacent to the edge of the third end is different from the distance between the end of the second lap wire 24 at the second end E2 away from the third end E3 and the second collector grid line 2121 adjacent to the edge of the third end. In the embodiment of the present application, the distance between the end of the first lap wire 22 at the first end E1 away from the third end E3 and the first collector grid line 2111 adjacent to the edge of the third end is longer than the distance between the end of the second lap wire 24 at the second end E2 away from the third end E3 and the second collector grid line 2121 adjacent to the edge of the third end, and the chamfer size of the first lap wire 22 at the first end E1 near the edge of the third end is longer, so that the current at the chamfer can be fully collected, which is beneficial to reducing the dead zone on the solar cell and reducing the performance loss of the solar cell.

[0075] Optionally, the number of first main joints P1 electrically connected to the first overlap wires 22 is equal to the number of second main joints N1 electrically connected to the second overlap wires 24, and the number of first auxiliary joints P2 electrically connected to the first overlap wires 22 is equal to the number of second auxiliary joints N2 electrically connected to the second overlap wires 24.

[0076] Optionally, the number of the first main joints P1 and the first auxiliary joints P2 located at the first end E1 and electrically connected to the first jumper 22 is equal, and the number of the second main joints N1 and the second auxiliary joints N2 located at the second end E2 and electrically connected to the second jumper 24 is equal. In other words, the arrangement of the first collector grid line 211 and the second collector grid line 212 at the first end E1 is asymmetrical to the arrangement of the first collector grid line 211 and the second collector grid line 212 at the second end E2.

[0077] Specifically, in this embodiment, a first main joint P1 is electrically connected to a first auxiliary joint P2 through a first jumper 22, and a second main joint N1 is electrically connected to a second auxiliary joint N2 through a second jumper 24. In this way, while ensuring that the main joint is electrically connected to the auxiliary joint, the number of interrupted collector grid lines in the collector grid line discontinuity area is as small as possible, achieving effective collection of anisotropic currents, which is beneficial to reducing dead zones on solar cells and further reducing performance losses of solar cells.

[0078] Optionally, the projection of the first main joint P1 at the first end E1 on a plane perpendicular to the first direction D1 and the projection of the second main joint N1 at the second end E2 on a plane perpendicular to the first direction D1 at least partially overlap. This arrangement facilitates uniform collection of current, avoids mismatching of currents collected by main joints of different polarities, reduces the difficulty of battery interconnection, improves the fault tolerance rate in the preparation process of the electrode structure, and has high production efficiency.

[0079] Furthermore, the number of the first main joints at the first end E1 is the same as the number of the second main joints at the second end E2, and the number of the first auxiliary joints at the first end E1 is the same as the number of the second auxiliary joints at the second end E2. In this way, the collector grid line between the first end and the second end can be interrupted as little as possible, thereby avoiding the formation of a dead zone on the solar cell and improving the output efficiency of the current.

[0080] In addition, in the first direction D1, the number of the discontinuous second collector grid lines 212 interrupted by the first main joint P1 located at the first end E1 is the same as the number of the discontinuous first collector grid lines 211 interrupted by the second main joint N1 located at the second end E2, and the discontinuous second collector grid lines 212 interrupted by the first main joint P1 and the discontinuous first collector grid lines 211 interrupted by the second main joint N1 are alternately distributed along the second direction D2. Figure 2 and Figure 3 As shown in FIG. 1 , the discontinuous second collector grid lines 212a interrupted by the first main joint P1 and the discontinuous first collector grid lines 211a interrupted by the second main joint N1 are not symmetrically arranged. Specifically, the number of discontinuous second collector grid lines 212 interrupted by the first main joint P1 is two, and the two second collector grid lines 212 are marked with reference numeral 212a, and the number of discontinuous first collector grid lines 211 interrupted by the second main joint N1 is two, and the two first collector grid lines 211 are marked with reference numeral 211a, and the two first collector grid lines 211a are respectively connected to Figure 2 The two first main joint portion collector gate lines 2112 shown in FIG. are collinear. In addition, the two second collector gate lines 212a are respectively connected to Figure 3The second main joint portion collector gate line 2122 shown in FIG. 1 is co-linear with a second bonding line collector gate line 2121 that is adjacent to the second main joint portion collector gate line 2122 in the second direction D2.

[0081] like Figures 1 to 3 As shown, the distance that the first overlap line 22 extends in the second direction D2 is greater than the distance that the second overlap line 24 extends in the second direction D2. Specifically, as shown in FIG. Figure 2 As shown, the first overlap line 22 extends a distance of 7d in the second direction D2, and as shown in FIG. Figure 3 As shown, the distance that the second overlap wire 24 extends in the second direction D2 is 6d, so that the first main joint P1 and the second main joint N1 are arranged so that the projection of the first main joint P1 on a plane perpendicular to the first direction D1 and the projection of the second main joint N1 on a plane perpendicular to the first direction D1 completely overlap. In this way, in the first direction D1, not only the layout of the collector grid lines is simplified, making the appearance of the electrode structure beautiful, but also the difficulty of electrical interconnection of the solar cell module is reduced, which is conducive to standardized operation during the welding process and improves the possibility of realizing automated mass production of solar cell modules. It should be noted that in other embodiments, the number of the intermittent second collector grid lines 212 adjacent to the first main joint P1 and the number of the intermittent first collector grid lines 211 adjacent to the second main joint N1 are not limited to the above.

[0082] Optionally, the projection of the first intermediate main joint on the plane perpendicular to the first direction D1, the projection of the second intermediate main joint on the plane perpendicular to the first direction D1, the projection of the first main joint P1 on the plane perpendicular to the first direction D1, and the projection of the second main joint N1 on the plane perpendicular to the first direction D1 completely overlap.

[0083] like Figure 4As shown, multiple collector gate lines located at the fourth end E4 form a third collector gate line area. In an embodiment of the present application, the third collector gate line area is another collector gate line discontinuity area, and the electrode structure also includes a first parallel overlap line and at least one first parallel main joint located in the other collector gate line discontinuity area, wherein a portion of the first collector gate lines 211 in the other collector gate line discontinuity area is electrically connected to the first parallel main joint through the first parallel overlap line, a portion of the first collector gate lines 211 in the other collector gate line discontinuity area is electrically connected to at least one first auxiliary joint through the first parallel overlap line, and a distance from one end of the first overlap line located at the third end E3 away from the third end E3 to the first collector gate line 211 adjacent to the edge of the third end is the same as a distance from one end of the first parallel overlap line located at the fourth end E4 away from the fourth end E4 to the first collector gate line 211 adjacent to the edge of the fourth end. Optionally, the number of the discontinuous second collector grid lines interrupted by the first main joint at the third end E3 is the same as the number of the discontinuous second collector grid lines interrupted by the first parallel main joint at the fourth end E4, that is, the electrode pattern near the first main joint at the third end E3 and the electrode pattern near the first parallel main joint at the fourth end E4 are arranged roughly symmetrically. Arranging in this way is conducive to standardized operation during welding.

[0084] Preferably, the electrode pattern at the third end E3 and the electrode pattern at the fourth end E4 are symmetrically designed, and the polarity of the first main joint at the third end E3 and the polarity of the first parallel main joint at the fourth end E4 are also correspondingly the same. By setting it in this way, the current mismatch at the third end E3 and the fourth end E4 of the photovoltaic component 1 can be avoided, and the welding difficulty of the joint can be reduced.

[0085] like Figure 4 As shown, at the first end E1, the electrode structure also includes a first parallel lap wire 26 and at least one first parallel main joint P3 located in another collector grid line discontinuity region, wherein part of the first collector grid line 211 in another collector grid line discontinuity region is electrically connected to the first parallel main joint P3 through the first parallel lap wire 26, part of the first collector grid line 211 in another collector grid line discontinuity region is electrically connected to at least one first auxiliary joint P2 through the first parallel lap wire 26, and the distance from one end of the first lap wire 22 located at the third end E3 away from the third end E3 to the first collector grid line 211 adjacent to the edge of the third end is the same as the distance from one end of the first parallel lap wire 26 located at the fourth end E4 away from the fourth end E4 to the first collector grid line 211 adjacent to the edge of the fourth end. Optionally, the number of first auxiliary joints electrically connected to the first parallel main joints does not exceed 3, so as to avoid increasing the path of current transmission and thus increasing the loss of current collection.

[0086] Specifically, in Figure 4 In the illustrated embodiment, the electrode structure is provided with a first parallel main joint P3, which is a joint closest to the fourth end E4 among all the joints adjacent to the first end E1. It should be noted that in other embodiments not shown in the present application, the electrode structure may also be provided with two or more first parallel main joints P3 to achieve effective collection of current. The first parallel main joint P3 may be directly electrically connected to a portion of the first collector grid line 211 of another collector grid line discontinuity area S1 located at the first end E1, or may be electrically connected to a portion of the first collector grid line 211 of another collector grid line discontinuity area S1 located at the first end E1 by means of a first parallel lap wire 26 to be described in detail later, so that the current collected by the first collector grid line 211 of another collector grid line discontinuity area S1 located at the first end E1 may be collected to the first parallel main joint P3. It should be noted that the collector grid lines electrically connected to the first parallel main joint P3 are all first collector grid lines 211, that is, the collector grid lines electrically connected to the first parallel main joint P3 are all same-polarity collector grid lines, and the first parallel main joint P3 and the first parallel overlap line 26 are both separated by a certain distance from the opposite-polarity second collector grid line 212, so that there is no connection with the second collector grid line 212, thereby avoiding short circuit.

[0087] The first parallel lap wire 26 is arranged at the edge of the electrode area A at the first end E1 and extends substantially in the second direction D2. Similar to the first lap wire 22, the first parallel lap wire 26 can be electrically connected to the first parallel main joint P3 through the first collector grid line 211 arranged between the first parallel lap wire 26 and the first parallel main joint P3. Optionally, the first parallel lap wire 26 can also be electrically connected to the first parallel main joint P3 via the first parallel connection line 25 arranged between the first parallel lap wire 26 and the first parallel main joint P3, wherein the width of the first parallel connection line 25 is greater than the width of the first collector grid line 211 to increase the reliability of current transmission. In addition, in the present embodiment, the distance that the first lap wire 22 extends in the second direction D2 and the distance that the first parallel lap wire 26 extends in the second direction D2 are both 7d. In this way, in the process of welding solar cells to form a battery string, it is conducive to standardized operation during the welding process.

[0088] Optionally, the distance between the first parallel main joint P3 adjacent to the first auxiliary joint P2 and the first collector grid line 211 adjacent to the fourth end edge is greater than the distance between the first parallel main joint P3 adjacent to the first auxiliary joint P2 and the first auxiliary joint P2 adjacent to the first parallel main joint P3. The width of the first parallel lap line 26 in the first direction D1 along the second direction D2 first increases and then decreases, and the first parallel lap line has different degrees of gradual change in width from the widest point to the direction of decreasing width. For example, the widths at the two ends along the second direction D2 are approximately the same, and the first parallel lap line 26 is widest at the position electrically connected to the first parallel main joint P3.

[0089] In addition, in the second direction D2, the third end E3 and the fourth end E4 of the electrode structure are provided with electrodes of the same polarity. On the one hand, from the perspective of the physical structure of the electrode, the area of ​​the emitter can be increased, and more emitter area means that more current transmission tasks can be carried; on the other hand, the tunneling passivation effect can be enhanced, effectively reducing the energy loss of the current during the tunneling process, and improving the transmission efficiency of the solar cell.

[0090] like Figure 5 As shown, the electrode structure is also provided with a second parallel main joint N3, which is a joint closest to the fourth end E4 among all the joints adjacent to the second end E2. It should be noted that in other embodiments not shown in the present application, the electrode structure may also be provided with two or more second parallel main joints N3 to achieve effective collection of current. The second parallel main joint N3 can be directly electrically connected to a portion of the second collector grid line 212 of another collector grid line discontinuity area S2 located at the second end E2, or electrically connected to a portion of the second collector grid line 212 of another collector grid line discontinuity area S2 located at the second end E2 by means of a second parallel lap wire 27 to be described in detail later, so that the current collected by the second collector grid line 212 of another collector grid line discontinuity area S2 located at the second end E2 can be collected to the second parallel main joint N3. It should be noted that the collector grid lines electrically connected to the second parallel main joint N3 are all second collector grid lines 212, that is, the collector grid lines electrically connected to the second parallel main joint N3 are all the same-sex collector grid lines, and the second parallel main joint N3 and the second parallel lap wire 27 are both separated by a certain distance from the first collector grid line 211 of the opposite sex, so that there is no connection with the first collector grid line 211, avoiding short circuit. Similarly, the second parallel main joint can be electrically connected to two or more second auxiliary joints. Optionally, the number of second auxiliary joints electrically connected to the second parallel main joint does not exceed 3, so as to avoid increasing the path of current transmission and thus increasing the loss of current collection.

[0091] The second parallel lap wire 27 is arranged at the edge of the electrode area A at the second end E2, and extends substantially in the second direction D2. Similar to the second lap wire 24, the second parallel lap wire 27 can be electrically connected to the second parallel main joint N3 through the second collector grid line 212 arranged between the second parallel lap wire 27 and the second parallel main joint N3. Optionally, the second parallel lap wire 27 can also be electrically connected to the second parallel main joint N3 via a second parallel connection line 28 arranged between the second parallel lap wire 27 and the second parallel main joint N3, wherein the width of the second parallel lap wire 27 is greater than the width of the second collector grid line 212 to increase the reliability of current transmission. In addition, in the present embodiment, the distance that the second lap wire 24 extends in the second direction D2 and the distance that the second parallel lap wire 27 extends in the second direction D2 are both 6d. In this way, in the process of welding solar cells to form a battery string, it is conducive to standardized operation during the welding process.

[0092] In addition, similar to the arrangement of the discontinuous first collector grid line and the discontinuous second collector grid line in the collector grid line discontinuity region at the third end E3, the number of discontinuous second collector grid lines interrupted by the first parallel main joint is the same as the number of discontinuous first collector grid lines interrupted by the second parallel main joint, and the discontinuous second collector grid lines interrupted by the first parallel main joint are alternately distributed along the second direction with the discontinuous first collector grid lines interrupted by the second parallel main joint. The specific arrangement method is described in the above description of the arrangement of the discontinuous first collector grid line and the discontinuous second collector grid line in the collector grid line discontinuity region at the third end E3, which will not be repeated here for the sake of brevity. That is to say, the electrode structures at the third end E3 and the fourth end E4 are roughly symmetrically arranged to facilitate standardized operations during welding.

[0093] Optionally, the distance between the second parallel main joint N3 adjacent to the second auxiliary joint N2 and the second collector grid line 212 adjacent to the fourth end edge is greater than the distance between the second parallel main joint N3 adjacent to the second auxiliary joint N2 and the second auxiliary joint N2 adjacent to the second parallel main joint N3. The width of the second parallel lap wire 27 along the second direction D2 in the first direction D1 first increases and then decreases, and the second parallel lap wire has different degrees of gradual change in width from the widest point to the direction of decreasing width. Exemplarily, the widths at the two ends along the second direction D2 are substantially the same, and the second parallel lap wire 27 is widest at the position electrically connected to the second parallel main joint N3.

[0094] Optionally, the collector grid lines in the collector grid line discontinuity region adjacent to the third end edge are continuous. Figure 2 and Figure 4As shown, the collector grid line adjacent to the edge of the third end in the collector grid line discontinuity region is the first collector grid line 211, and the first collector grid line 211 is not interrupted in the first direction D1. In this way, the collector grid lines can be interrupted as little as possible, thereby avoiding the formation of dead zones on the solar cell, and at the same time, the current at the edge of the battery substrate can also be fully collected, thereby improving the output efficiency of the current. It should be understood that the collector grid line adjacent to the edge of the fourth end in the collector grid line discontinuity region at the fourth end E4 can also be set to be continuous.

[0095] Optionally, in the collector grid line continuous region, the length of at least one second collector grid line adjacent to the first main junction is smaller than the lengths of the remaining second collector grid lines. Figure 2 In the local area shown, in the first direction D1, the number of the interrupted second collector grid lines 212 interrupted by the first main joint P1 is one, and there is also an interrupted second collector grid line interrupted by the first parallel main joint P3 at the corresponding position of the fourth end, and these two second collector grid lines 212 are marked with reference numerals 212b, and the length of this second collector grid line 212b is less than the length of the remaining second collector grid lines 212 in the collector grid line continuous area. In this way, while ensuring that the first main joint is electrically connected to the first auxiliary joint, the number of interrupted second collector grid lines in the collector grid line interruption area is as small as possible, achieving effective collection of anisotropic currents, which is beneficial to reducing the dead zone on the solar cell and reducing the performance loss of the solar cell.

[0096] Optionally, in the collector gate line continuous region, at least one second collector gate line 212b whose length is smaller than the remaining second gate lines and is adjacent to the first main junction is electrically connected to the second auxiliary junction. That is to say, there is an isolation region between the doped semiconductor layers corresponding to the first main junction and the first auxiliary junction, while there is no isolation region between the doped semiconductor layers corresponding to the second main junction and the second auxiliary junction, where the isolation region is used to isolate two doped semiconductor layers with opposite polarities. . Arranged in this way, the first main junction P1 and the first auxiliary junction P2 can be well interconnected with as few collector gate lines interrupted as possible between the first end and the second end.

[0097] Optionally, the solar cell 100 may further include a doped semiconductor layer, which is disposed between the electrode structure and the cell substrate 10 and is electrically connected to the electrode structure. Specifically, the doped semiconductor layer may be disposed on or in the cell substrate 10, and at least the first collector grid line 211 and the second collector grid line 212 are electrically connected to the doped semiconductor layer.

[0098] Optionally, a doped semiconductor layer is provided in the region where the projection of the electrode structure is located on the battery substrate 10. This arrangement can increase the tunnel passivation area and avoid the short circuit problem caused by electrode burn-through.

[0099] The embodiment of the present application further provides a photovoltaic module. The photovoltaic module includes at least two solar cells 100 described above. At least two solar cells 100 in the photovoltaic module can be connected in series and / or in parallel via a conductive interconnect (such as a welding ribbon) to form a cell string.

[0100] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "an example", "some embodiments", or "preferred embodiment" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0101] The embodiments of the present application are described in detail above. However, aspects of the present application are not limited to the above embodiments. Various modifications and substitutions may be applied to the above embodiments without departing from the scope of the present application.

Claims

1. A solar cell, characterized in that: include: a battery substrate, the battery substrate comprising a first end and a second end disposed opposite to each other in a first direction and a third end and a fourth end disposed opposite to each other in a second direction, wherein the second direction intersects the first direction; and An electrode structure, the electrode structure is located on the battery substrate, and the electrode structure comprises: a plurality of collector gate lines, the plurality of collector gate lines comprising a first collector gate line and a second collector gate line having opposite polarities and both extending in a first direction, at least a portion of the first collector gate lines and at least a portion of the second collector gate lines being alternately distributed in the second direction, the plurality of collector gate lines located at the third end portion forming a first collector gate line region, and the plurality of collector gate lines located between the third end portion and the fourth end portion forming a second collector gate line region; at least one first main junction, the first main junction being located in the first collector gate region and electrically connected to at least part of the first collector gate in the first collector gate region; a plurality of first auxiliary joints, the plurality of first auxiliary joints being located in the second collector gate line region, wherein a portion of the first main joints and a portion of the first auxiliary joints are at least partially collinear in the second direction, and at least one of the first auxiliary joints is electrically connected to one of the first collector gate lines in the second collector gate line region; and A first jumper wire, part of the first collector gate line in the first collector gate line area is electrically connected to the first main joint through the first jumper wire, and part of the first collector gate line in the first collector gate line area is electrically connected to at least one of the first auxiliary joints through the first jumper wire.

2. The solar cell according to claim 1, characterized in that The first collector gate line region is a collector gate line discontinuous region, and the second collector gate line region is a collector gate line continuous region.

3. The solar cell according to claim 2, characterized in that: The first main joint is located at the first end and is electrically connected to the first collector gate line in the collector gate line discontinuity area located at the first end. The multiple first auxiliary joints are located at the first end, and the first auxiliary joints located at the first end are electrically connected to the first collector gate line in the collector gate line continuous area located at the first end. The first jumper is located at the first end, and the first collector gate line in the collector gate line discontinuity area is electrically connected to the first main joint at the first end through the first jumper, and the first collector gate line in the collector gate line discontinuity area is electrically connected to at least one of the first auxiliary joints at the first end through the first jumper.

4. The solar cell according to claim 3, characterized in that: The electrode structure further comprises: at least one second main joint, the second main joint being located in the collector grid line discontinuity region and electrically connected to at least part of the second collector grid line in the collector grid line discontinuity region; a plurality of second auxiliary joints, the plurality of second auxiliary joints being located in the collector grid line continuous region, wherein part of the second main joints and part of the second auxiliary joints are at least partially collinear in the second direction, and at least one of the second auxiliary joints is electrically connected to one of the second collector grid lines in the collector grid line continuous region; and A second jumper wire, a portion of the second collector gate line in the collector gate line discontinuity area is electrically connected to the second main joint through the second jumper wire, and a portion of the second collector gate line in the collector gate line discontinuity area is electrically connected to at least one of the second auxiliary joints through the second jumper wire.

5. The solar cell according to claim 4, characterized in that: The second main joint is located at the second end and is electrically connected to the second collector gate line in the collector gate line discontinuity area at the second end. The multiple second auxiliary joints are located at the second end, and the second auxiliary joints at the second end are electrically connected to the second collector gate line in the collector gate line continuous area at the second end. The second jumper is located at the second end, and the second collector gate line in the collector gate line discontinuity area is electrically connected to the second main joint at the second end through the second jumper, and the second collector gate line in the collector gate line discontinuity area is electrically connected to at least one of the second auxiliary joints at the second end through the second jumper.

6. The solar cell according to claim 5, characterized in that: The distance between the first jumper wire at the first end and the first collector grid line adjacent to the edge of the third end is different from the distance between the second jumper wire at the second end and the second collector grid line adjacent to the edge of the third end.

7. The solar cell according to claim 5, characterized in that: A projection of the first main joining portion at the first end portion on a plane perpendicular to the first direction at least partially overlaps with a projection of the second main joining portion at the second end portion on the plane perpendicular to the first direction.

8. The solar cell according to claim 5, characterized in that: The multiple collector gate lines located at the fourth end form another collector gate line discontinuity area, and the electrode structure also includes a first parallel overlap line and at least one first parallel main joint located in the other collector gate line discontinuity area, wherein a portion of the first collector gate line in the other collector gate line discontinuity area is electrically connected to the first parallel main joint through the first parallel overlap line, a portion of the first collector gate line in the other collector gate line discontinuity area is electrically connected to at least one first auxiliary joint through the first parallel overlap line, and a distance from one end of the first overlap line located at the third end away from the third end to the first collector gate line adjacent to the edge of the third end is the same as a distance from one end of the first parallel overlap line located at the fourth end away from the fourth end to the first collector gate line adjacent to the edge of the fourth end.

9. The solar cell according to claim 5, characterized in that: In the first direction, the number of intermittent second collector grid lines interrupted by the first main joint located at the first end is the same as the number of intermittent first collector grid lines interrupted by the second main joint located at the second end, and the intermittent second collector grid lines interrupted by the first main joint and the intermittent first collector grid lines interrupted by the second main joint are alternately distributed along the second direction.

10. The solar cell according to claim 8, characterized in that The number of the first auxiliary joints electrically connected to the first main joint does not exceed 3; and / or the number of the second auxiliary joints electrically connected to the second main joint does not exceed 3; and / or the number of the first auxiliary joints electrically connected to the first parallel main joint does not exceed 3.

11. The solar cell according to claim 8, characterized in that The distance between the first main joint portion adjacent to the first auxiliary joint portion and the first collector grid line adjacent to the third end edge is greater than the distance between the first main joint portion adjacent to the first auxiliary joint portion and the first auxiliary joint portion adjacent to the first main joint portion; and / or The distance between the second main joint portion adjacent to the second auxiliary joint portion and the second collector grid line adjacent to the third end edge is greater than the distance between the second main joint portion adjacent to the second auxiliary joint portion and the second auxiliary joint portion adjacent to the second main joint portion; and / or The distance between the first parallel main joint adjacent to the first auxiliary joint and the first collector grid line adjacent to the fourth end edge is greater than the distance between the first parallel main joint adjacent to the first auxiliary joint and the first auxiliary joint adjacent to the first parallel main joint.

12. The solar cell according to claim 11, characterized in that: The first overlap line, and / or the second overlap line, and / or the first parallel overlap line, have a width in the first direction that first increases and then decreases along the second direction; the first overlap line is widest at a position where it is electrically connected to the first main joint, the second overlap line is widest at a position where it is electrically connected to the second main joint, and the first parallel overlap line is widest at a position where it is electrically connected to the first parallel main joint; the first overlap line or the second overlap line or the first parallel overlap line have different degrees of gradual width change from the widest point toward a direction in which the width decreases.

13. The solar cell according to any one of claims 1 to 12, characterized in that The first collector gate line adjacent to the third end edge in the collector gate line discontinuity region is continuous.

14. The solar cell according to any one of claims 1 to 12, characterized in that In the collector gate line continuous region, the length of at least one of the second collector gate lines adjacent to the first main junction is shorter than the lengths of the remaining second collector gate lines.

15. The solar cell according to any one of claims 14, characterized in that: In the collector gate line continuous region, at least one second collector gate line that is shorter than the remaining second gate lines and is adjacent to the first main junction is electrically connected to the second auxiliary junction.

16. The solar cell according to any one of claims 1 to 12, characterized in that The solar cell further comprises a doped semiconductor layer, which is disposed between the electrode structure and the cell substrate and is electrically connected to the electrode structure.

17. A photovoltaic module, characterized in that: Comprising at least two solar cells according to any one of claims 1 to 16.

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