Solar cell and solar module

Abstract

The embodiment of the utility model relates to a solar cell and a solar module. The solar cell comprises a cell substrate, a first grid line, a second grid line, a first end bonding pad, a second end bonding pad and a lapping line, wherein the first grid line and the second grid line are opposite in polarity. The battery substrate includes a first edge and a second edge opposite in a first direction and a third edge and a fourth edge opposite in a second direction. At least part of the first grid lines and at least part of the second grid lines are alternately distributed in the second direction. The first end portion bonding pad is the bonding pad closest to the third edge among all the bonding pads adjacent to the first edge. And the second end part bonding pad is the bonding pad closest to the third edge in all the bonding pads adjacent to the second edge. And the lapping wire is lapped with the adjacent first grid line after being connected with the first end bonding pad, and forms an accommodating area with the adjacent first grid line on the surface of the battery substrate. The second grid line adjacent to the adjacent first grid line comprises a bending section which is bent into the accommodating area. The first gate line between the second end pad and the third edge extends only in the first direction.

Description

Technical Field

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

[0002] In the existing electrode structure of solar cells, some grid lines are provided with a bend section near the edge of the solar cell to effectively collect carriers. However, when the grid lines are printed, there is a problem that the bend section is easily broken, resulting in a decrease in the yield of the solar cell. Utility Model Content

[0003] The first aspect of the present application provides a solar cell. The solar cell includes a cell substrate and an electrode structure. The cell substrate includes a plurality of cell edges. The plurality of cell edges include a first edge and a second edge that are opposite to each other in a first direction and a third edge and a fourth edge that are opposite to each other in a second direction, and the second direction intersects with the first direction. The electrode structure is located on the cell substrate. The electrode structure includes a plurality of grid lines, a first end pad, a second end pad, and a lap wire. The plurality of grid lines include a first grid line and a second grid line with opposite polarities. At least part of the first grid lines and at least part of the second grid lines are alternately distributed along the second direction. The first end pad is at least one pad that is closest to the third edge among all pads that are adjacent to the first edge, and is electrically connected to part of the first grid lines. The second end pad is at least one pad that is closest to the third edge among all pads that are adjacent to the second edge, and is electrically connected to part of the second grid lines. After the lap wire is connected to the first end pad, it extends toward the third edge and laps with the adjacent first grid line. The adjacent first grid line is at least one first grid line that is adjacent to the first end pad and connected to the lap wire. The first grid line connected to the first end pad and the first edge of the battery substrate is connected to the first end pad and the first grid line of the overlapped wire and the adjacent first grid line or the overlapped wire and the adjacent first grid line and the first grid line located between the first end pad and the first edge forms an accommodation area on the surface of the battery substrate. At least one second grid line adjacent to the adjacent first grid line includes a main section extending along the first direction and at least one bending section connecting the main section and bending into the accommodation area. The first grid line between the second end pad and the third edge only extends along the first direction.

[0004] In the solar cell of the first aspect of the present application, the grid line (i.e., the second grid line) between the first end pad and the third edge and the polarity opposite to the first end pad is set to bend into the bending section of the accommodating area, so that the carriers with different polarity from the first end pad in the accommodating area can be effectively collected, effectively avoiding the formation of dead zones and reducing the performance loss of the solar cell. All the grid lines (i.e., the first grid lines) between the second end pad and the third edge and the polarity opposite to the second end pad only extend along the first direction without the bending section. In this way, it is beneficial to reduce the total number of grid lines with bending sections in the electrode structure, and then it is beneficial to reduce the problem of easy disconnection at the bending section when the grid lines are printed, and ultimately it is beneficial to improve the yield of the solar cell.

[0005] In summary, in the solar cell of the first aspect of the present application, the grid lines in the region near the first edge of the cell substrate and the opposite polarity to the first end pad are provided with a bending section, which is conducive to achieving a better edge convergence effect; while the grid lines in the region near the second edge of the cell substrate and the opposite polarity to the second end pad are not provided with a bending section, which is conducive to reducing the total number of bending sections in the electrode structure, thereby reducing the phenomenon of grid line breakage during printing. Therefore, the solar cell of the first aspect of the present application is conducive to achieving a balance between the edge convergence effect and the grid line printing quality.

[0006] In some embodiments, all gate lines connected to the side of the first end pad facing the first edge are first gate lines.

[0007] In some embodiments, all gate lines connected to the side of the second end pad facing the second edge are second gate lines.

[0008] In some embodiments, the number of first gate lines connected to the side of the first end pad facing the second edge is less than the number of second gate lines corresponding to the side of the first end pad facing the second edge. The number of second gate lines connected to the side of the second end pad facing the first edge is more than the number of first gate lines corresponding to the side of the second end pad facing the first edge.

[0009] It should be noted that, in the embodiment of the present application, the “corresponding” in “the second gate line corresponding to the side of the first end pad facing the second edge” means that the position correspondence between the second gate line and the first end pad is that the first end pad is located on the extension line of the second gate line along the first direction, or in other words, the second gate line passing through the first end pad along the extension line of the first direction is the second gate line corresponding to the first end pad. The “corresponding” in “the first gate line corresponding to the side of the second end pad facing the first edge” means that the position correspondence between the first gate line and the second end pad is that the second end pad is located on the extension line of the first gate line along the first direction, or in other words, the first gate line passing through the second end pad along the extension line of the first direction is the first gate line corresponding to the second end pad.

[0010] In some embodiments, between the third edge and the first end pad, between the fourth edge and the first end pad, the gate lines closest to the first end pad are all first gate lines. Between the fourth edge and the second end pad, the gate line closest to the second end pad is the first gate line. A second gate line closest to the third edge among all second gate lines connected to the second end pad on one side toward the first edge is defined as a termination second gate line. A first gate line closest to the side of the termination second gate line toward the third edge is defined as a first gate line next to the first gate line. Along the second direction, the projections of the first gate line next to the second end pad do not overlap.

[0011] In some embodiments, the number of first gate lines connected to the side of the first end pad facing the second edge is greater than the number of second gate lines corresponding to the side of the first end pad facing the second edge. The number of second gate lines connected to the side of the second end pad facing the first edge is less than the number of first gate lines corresponding to the side of the second end pad facing the first edge.

[0012] In some embodiments, between the third edge and the second end pad, between the fourth edge and the second end pad, the gate line closest to the second end pad is the second gate line. Between the fourth edge and the first end pad, the gate line closest to the first end pad is the second gate line. A first gate line closest to the third edge among all first gate lines connected to the first end pad on one side toward the second edge is defined as a termination first gate line. A second gate line closest to the side of the termination first gate line toward the third edge is defined as a second gate line next to the second gate line. The distance between the end of the second gate line next to the end of the bending section corresponding thereto is 1.5 to 2 times the length of the first end pad along the first direction.

[0013] In some embodiments, the distance between any two adjacent first grid lines is Z, and along the second direction, the length of the overlap line is L, and the integer part of the ratio of L and Z is N, where N is equal to the number of bending sections between the first end pad connected by the overlap line and the nearest battery edge.

[0014] In some embodiments, the distance from one side of the first end pad close to the third edge to the third edge is equal to the distance from one side of the second end pad close to the third edge to the third edge, or, the distance between any two adjacent first gate lines is Z, and the difference between the distance from one side of the first end pad close to the third edge to the third edge and the distance from one side of the second end pad close to the third edge to the third edge is less than 0.5Z.

[0015] In some embodiments, the width of the jumper line is the same as that of the first gate line, there are at least two jumpers, and each jumper line extends from an adjacent first gate line electrically connected thereto to the inside of the first end pad.

[0016] In some embodiments, the width of the jumper line is greater than the width of the first gate line, and the jumper line extends from the first end pad connected to the jumper line beyond the first gate line connected to the jumper line.

[0017] In some embodiments, the bonding wire is connected to at least one first gate wire located between the first edge and the first end pad.

[0018] In some embodiments, the electrode structure further includes a first side grid, which is adjacent to the first edge, extends along the second direction, and is connected to at least a portion of the first grid lines.

[0019] In some embodiments, the electrode structure further includes a second side grid, which is adjacent to the second edge, extends along the second direction, and is connected to at least a portion of the second grid line.

[0020] In some embodiments, the electrode structure further includes a first bus line, opposite ends of which are respectively connected to the first side grid and the first end pad, and a width of the first bus line is greater than a width of the grid line.

[0021] In some embodiments, the electrode structure further includes a second bus line, opposite ends of which are respectively connected to the second side grid and the second end pad, and a width of the second bus line is greater than a width of the grid line.

[0022] In some embodiments, the first side grid, and / or the second side grid, has a width that increases in the first direction along the second direction.

[0023] In some embodiments, the width of the first side grid and / or the second side grid in the first direction increases and then decreases along the second direction, the first side grid is widest where it connects to the first bus bar, and the second side grid is widest where it connects to the second bus bar.

[0024] The second aspect of the present application further provides a solar energy component, which comprises at least two solar cells according to the first aspect of the present application.

[0025] The second aspect of the present application has at least the same advantages as the solar cell of the first aspect of the present application, which will not be described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 FIG. 1 is a schematic plan view of a solar cell according to the first embodiment of the present application.

[0027] Figure 2 It is a partial schematic diagram of a first electrode structure of a solar cell at a first end pad according to an embodiment of the present application.

[0028] Figure 3 It is a partial schematic diagram of a first electrode structure of a solar cell at a second end pad according to an embodiment of the present application.

[0029] Figure 4 It is a partial schematic diagram of a second electrode structure of a solar cell at a first end pad according to an embodiment of the present application.

[0030] Figure 5 It is a partial schematic diagram of a second electrode structure of a solar cell at a second end pad according to an embodiment of the present application.

[0031] Figure 6 FIG. 1 is a schematic plan view of a solar cell according to a second embodiment of the present application.

[0032] Description of main component symbols:

[0033] Solar cell 100, 200

[0034] Battery substrate 10, 10'

[0035] Battery Edge E

[0036] First Edge E1

[0037] Second Edge E2

[0038] Third Edge E3

[0039] The Fourth Edge E4

[0040] Electrode areas A1, A2

[0041] Blank Area B

[0042] Accommodation Area C

[0043] Electrode structures 20a, 20c

[0044] Gate line 21

[0045] The first gate line 211

[0046] Adjacent to the first gate line 211a

[0047] Close to the first gate line 211b

[0048] Terminating the first gate line 211c

[0049] The second gate line 212

[0050] Main section 2121

[0051] Bending section 2122

[0052] Terminating the second gate line 212a

[0053] Close to the second gate line 212c

[0054] First end pad P1

[0055] Second end pad P2

[0056] Lap line 22

[0057] Overlap 23

[0058] First side grid 24

[0059] First busbar 25

[0060] Second side grid 26

[0061] Second bus line 27

[0062] First direction D1

[0063] Second direction D2 DETAILED DESCRIPTION

[0064] Figure 1 FIG. 1 is a schematic plan view of a solar cell according to an embodiment of the present application. Figure 1 As shown, the solar cell 100 includes a cell substrate 10, an electrode region A1 located on the cell substrate 10, and an electrode region A2 located on the cell substrate 10. The solar cell 100 may be a back contact solar cell, and the surface where the electrode region A1 and the electrode region A2 are located is the backlight surface of the cell substrate 10. The cell substrate 10 is used to generate and separate carriers, and the regions corresponding to the electrode region A1 and the electrode region A2 are respectively provided with electrode structures for collecting and conducting carriers.

[0065] Specifically, the battery substrate 10 includes a plurality of battery edges E. The plurality of battery edges E include a first edge E1, a second edge E2, a third edge E3 and a fourth edge E4. The first edge E1 and the second edge E2 are arranged relatively to each other along a first direction D1. The third edge E3 and the fourth edge E4 are arranged relatively to each other along a second direction D2. The first direction D1 intersects the second direction D2. In this embodiment, the first direction D1 is perpendicular to the second direction D2. For the convenience of description below, the direction from the first edge E1 to the second edge E2 is defined as the positive direction of the first direction D1, and the direction from the fourth edge E4 to the third edge E3 is defined as the positive direction of the second direction D2.

[0066] The battery substrate 10 further includes a blank area B for cutting. The electrode area A1 and the electrode area A2 are respectively located at two opposite sides of the blank area B along the second direction D2.

[0067] In some embodiments, the electrode structures in the electrode region A1 and the electrode region A2 are axially symmetrical as a whole, or in other words, the electrode patterns of the electrode region A1 and the electrode pattern of the electrode region A2 are axially symmetrical about the center line of the blank region B. The structures of the two sub-sheets obtained after cutting along the blank region B are exactly the same. In this case, one of the two sub-sheets of each whole solar cell cut along the blank region B needs to be rotated 180° in the process of forming a solar cell string, and then electrically connected to the other sub-sheet through a conductive interconnect (such as a solder strip).

[0068] In other embodiments, the electrode patterns of electrode region A1 and electrode region A2 are centrally symmetrical as a whole, or in other words, the electrode pattern of electrode region A2 can be obtained by rotating the electrode pattern of electrode region A1 by 180°. Of the two sub-sheets obtained after cutting along the blank region B, one sub-sheet has the same electrode structure as the other sub-sheet after rotating 180°. In this case, the two sub-sheets cut from each whole solar cell do not need to be rotated in the process of forming a solar cell string, and can be electrically connected through a conductive interconnect (such as a solder strip).

[0069] The following combination Figure 2 and Figure 3 The specific structure of the electrode structure 20a according to an embodiment of the present application is described. The electrode pattern in the electrode area A1 and / or the electrode pattern in the electrode area A2 may be the electrode structure 20a.

[0070] like Figure 2 As shown, the electrode structure 20a includes a plurality of gate lines 21. Specifically, the gate lines 21 include a plurality of first gate lines 211 and a plurality of second gate lines 212. At least part of the first gate lines 211 and at least part of the second gate lines 212 are alternately distributed along the second direction D2. The first gate lines 211 and the second gate lines 212 have opposite polarities. For example, the first gate line 211 is a positive gate line, and the second gate line 212 is a negative gate line; or the first gate line 211 is a negative gate line, and the second gate line 212 is a positive gate line.

[0071] It should be noted that, for the sake of clarity, Figure 2 and Figure 3 In the figure, the first gate lines 211 are drawn with solid lines, and the second gate lines 212 are 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 gate lines 211 and the second gate lines 212.

[0072] The electrode structure 20a further includes a first end pad P1. The first end pad P1 is at least one pad closest to the third edge E3 among all pads adjacent to the first edge E1. The first end pad P1 is electrically connected to a portion of the first gate line 211.

[0073] Specifically, the gate lines 21 connected to the side of the first end pad P1 toward the first edge E1 are all first gate lines 211. That is, the gate lines 21 connected to the side of the first end pad P1 toward the first edge E1 are all homogeneous gate lines, and there are no heterogeneous gate lines with bending sections. In this way, it is beneficial to reduce the total number of gate lines with bending sections in the electrode structure 20a, and further to reduce the problem of easy disconnection at the bending section when the gate lines 21 are printed, which is ultimately beneficial to improve the yield of the solar cell.

[0074] In addition, the number of first grid lines 211 connected to the side of the first end pad P1 facing the second edge E2 is less than the number of second grid lines 212 corresponding to the side of the first end pad P1 facing the second edge E2. In this way, in the first direction D1, there are opposite grid lines connected on the opposite sides of the first end pad P1, which realizes the effective collection of opposite carriers, helps to reduce the dead zone on the solar cell and reduce the loss of solar cell performance.

[0075] In this embodiment, the size of the first end pad P1 along the second direction D2 is greater than one gate line spacing and less than two gate line spacings. The gate line spacing of the present application refers to the spacing between adjacent first gate lines along the second direction or the spacing between adjacent second gate lines along the second direction. It is selected according to actual needs and will not be repeated below. Here, one gate line spacing is the spacing between adjacent first gate lines along the second direction. The number of first gate lines 211 connected to the side of the first end pad P1 toward the second edge E2 is one, and the number of second gate lines 212 corresponding to the side of the first end pad P1 toward the second edge E2 is two. In other embodiments, the size of the first end pad P1 along the second direction D2, the number of first gate lines 211 connected to the side of the first end pad P1 toward the second edge E2, and the number of second gate lines 212 corresponding to the side of the first end pad P1 toward the second edge E2 are not limited to the above.

[0076] The electrode structure 20a further includes a bonding wire 22. The bonding wire 22 is connected to the first end pad P1, extends toward the third edge E3 and is connected to the adjacent first gate line 211a. The adjacent first gate line 211a is at least one first gate line 211 adjacent to the first end pad P1 and connected to the bonding wire 22.

[0077] In this embodiment, the number of adjacent first gate lines 211a is two. In other embodiments, the number of adjacent first gate lines 211a is not limited thereto. In this embodiment, the width of the lap wire 22 is the same as the width of the first gate line 211. The number of the lap wire 22 is two. Each lap wire 22 extends to the inside of the first end pad P1 from the adjacent first gate line 211a electrically connected thereto. In the two lap wires 22, the lap wire 22 near the first edge E1 is overlapped with the first gate line 211 between the first side grid 24 and the first end pad P1.

[0078] Of the two lap wires 22, the lap wire 22 close to the first edge E1 and the two adjacent first grid wires 211a form a receiving area C on the surface of the battery substrate 10. The second grid wire 212 adjacent to the adjacent first grid wire 211a includes a main section 2121 extending along the first direction D1 and a bending section 2122 connecting the main section 2121 and bending into the receiving area C. In this way, by setting the bending section 2122, the carriers with different polarities from the first end pad P1 in the receiving area C can be effectively collected, further reducing the performance loss of the solar cell. In this embodiment, a second grid wire 212 adjacent to the adjacent first grid wire 211a is provided with a bending section 2122. In other embodiments, two or more second grid wires 212 adjacent to the adjacent first grid wire 211a have a bending section 2122.

[0079] In this embodiment, the number of the bending segments 2122 in a second gate line 212 adjacent to the first gate line 211a is one. In other embodiments, in the second gate line 212 having the bending segments 2122, the number of the bending segments 2122 is not limited thereto, for example, it can be two or more than two.

[0080] The electrode structure 20a further includes a lap portion 23. The lap portion 23 protrudes from the top edge of the first end pad P1 near the third edge E3 toward the third edge E3. The width of the lap portion 23 is greater than the width of the lap line 22. The number of the lap portions 23 is the same as the number of the lap lines 22, and they are arranged one by one. Each lap line 22 extends through a corresponding lap portion 23.

[0081] In this embodiment, there are two overlapping portions 23. The two overlapping portions 23 are arranged in a one-to-one correspondence with the two overlapping lines 22. In other embodiments, the number of overlapping lines 22 and overlapping portions 23 is not limited to the above.

[0082] In some embodiments, the overlap wire 22 and the adjacent first grid line 211a connected to the overlap wire 22 are integrally formed, and the integral forming here may mean that the two are printed together. In this case, the overlap wire 22 and the first 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 overlap wire 22 and the adjacent first grid line 211a are formed in batches, resulting in processing errors and the overlap wire 22 and the pad, and the first grid line 211 and the pad connected thereto cannot form an effective electrical connection. The integral forming can ensure the connection reliability between the overlap wire 22, the adjacent first grid line 211a, and the pad.

[0083] In some embodiments, the bonding wire 22 and the first gate line 211 are integrally formed. The integral forming method is as described above and will not be described in detail.

[0084] The grid line 21 between the third edge E3 and the first end pad P1 and the closest to the first end pad P1 is the first grid line 211. It should be noted that in the process of welding solar cells to obtain a battery string, the end of the conductive interconnect (such as a soldering strip) will produce an unstable bend in the sharp corner area due to the cutting effect, and there may be a risk of puncturing the insulating glue and causing a short circuit. Since the grid line 21 between the third edge E3 and the first end pad P1 and the closest to the first end pad P1 is a grid line with the same polarity as the first end pad P1, rather than a grid line with the opposite polarity to the first end pad P1, it is helpful to avoid the risk of short circuit at the end of the soldering strip.

[0085] The arrangement rule of the plurality of grid lines 21 on the side of the first end pad P1 facing the second edge E2 is: a first grid line 211 and a second grid line 212 are alternately distributed. Between the fourth edge E4 and the first end pad P1, the grid line 21 closest to the first end pad P1 is also the first grid line 211. In this way, the number of first grid lines 211 connected to the side of the first end pad P1 facing the second edge E2 is less than the number of second grid lines 212 corresponding to the side of the first end pad P1 facing the second edge E2. Since the grid lines 21 connected to the side of the first end pad P1 facing the first edge E1 are all first grid lines 211, therefore, in the first direction D1, there are opposite grid lines docking on the opposite sides of the first end pad P1, which realizes the effective collection of opposite carriers, which is conducive to reducing the dead zone on the solar cell and reducing the loss of solar cell performance.

[0086] The electrode structure 20a further includes a first side grid 24. The first side grid 24 is adjacent to the first edge E1, extends substantially along the second direction D2, and is connected to at least part of the first grid lines 211. Specifically, the first side grid 24 extends along the first edge E1 to be adjacent to the blank area B. Part of the first grid lines 211 between the first end pad P1 and the third edge E3, and part of the first grid lines 211 between the first end pad P1 and the blank area B are connected to the first side grid 24. In this way, it is beneficial to realize the collection of carriers of the solar cell in the area close to the first edge E1.

[0087] Of the two adjacent first grid lines 211a, the one close to the first end pad P1 is overlapped with the two overlap lines 22, and then extends to connect with the first side grid 24. Of the two adjacent first grid lines 211a, the one close to the third edge E3 has a gap with the first side grid 24, and the bent section 2122 has a portion located in the gap and extending along the second direction D2. In this way, the bent section 2122 includes both a portion located in the accommodating area C and extending along the first direction D1, and a portion located in the gap and extending along the second direction D2, that is, the bent section 2122 is distributed in more directions, which increases the coverage area of ​​the second grid line 212 on the battery substrate 10, thereby improving the collection capacity of carriers with different polarities of the first end pad P1.

[0088] The electrode structure 20a further includes a first bus line 25. The opposite ends of the first bus line 25 are respectively connected to the first side grid 24 and the first end pad P1. The width of the first bus line 25 is greater than the width of the grid line 21. The larger the width of the first bus line 25, the smaller the resistance when transmitting carriers, which is more conducive to the transmission of current.

[0089] Along the second direction D2, the width of the first side grid 24 in the first direction D1 increases first and then decreases. The position where the first side grid 24 is connected to the first bus bar 25 is the widest. Specifically, the position where the first side grid 24 is connected to the first bus bar 25 is the widest, so that the resistance of the first side grid 24 at the position corresponding to the first bus bar 25 is the smallest, which is conducive to ensuring the busbar effect at the position of the first bus bar 25. In addition, along the second direction D2, the width of the first side grid 24 in the first direction D1 increases first and then decreases, so that the line width of the first side grid 24 set at the position with a smaller busbar effect is smaller, which is conducive to reducing the use of materials (such as silver paste) of the first side grid 24, thereby reducing production costs.

[0090] In the negative direction of the second direction D2, after the first side grid 24 is connected to the first bus line 25, the width of the first side grid 24 decreases suddenly. That is, with the first bus line 25 as the boundary, the reduction degree of the portion of the first side grid 24 located between the first bus line 25 and the fourth edge E4 is greater than the reduction degree of the portion of the first side grid 24 located between the first bus line 25 and the third edge E3. Because the first grid lines 211 between the first end pad P1 and the third edge E3 all need to rely on the first side grid 24 to collect carriers to the first end pad P1 and then lead them out, the portion of the first side grid 24 located between the first bus line 25 and the third edge E3 requires a stronger carrier collection ability, and the volume of this portion of the first side grid 24 needs to be larger. Therefore, the above scheme can better reduce the use of materials (such as silver paste) of the first side grid 24 while ensuring the convergence effect, thereby reducing the production cost.

[0091] The first busbar 25 is collinear with a first grid line 211. Each first grid line 211 connected to the first end pad P1 in the negative direction of the first direction D1 is collinear with a corresponding second grid line 212 in the positive direction of the first end pad P1 in the first direction D1. In this way, it is beneficial to improve the fault tolerance rate in the preparation process of the grid line 21, reduce the complexity of the processing, and make the stress of the edge area of ​​the solar cell more uniform, which is beneficial to reduce the probability of the solar cell breaking.

[0092] Along the second direction D2, there is a first gate line 211 connected to the first end pad P1 on opposite sides of the first bus line 25. More specifically, the two first gate lines 211 connected to the first end pad P1 on opposite sides of the first bus line 25 along the second direction D2 are symmetrically distributed about the first bus line 25. In this way, the electrode structure 20a has a beautiful appearance, and the first end pad P1 is more balanced in collecting carriers.

[0093] In this embodiment, there is a gap between the first gate line 211 and the first side grid 24 between the first end pad P1 and the first edge E1 to save materials for gate line printing. In other embodiments, the first gate line 211 between the first end pad P1 and the first edge E1 can be connected to the first side grid 24 to increase the reliability of carrier transmission and avoid the risk of bus failure of the first end pad P1 after the first bus line 25 is broken.

[0094] like Figure 3 As shown, the electrode structure 20a further includes a second end pad P2. The second end pad P2 is at least one pad closest to the third edge E3 among all pads adjacent to the second edge E2. The second end pad P2 is electrically connected to a portion of the second gate line 212.

[0095] Specifically, the grid lines 21 connected to the side of the second end pad P2 toward the second edge E2 are all second grid lines 212. That is, the grid lines 21 connected to the side of the second end pad P2 toward the second edge E2 are all the same-sex grid lines (i.e., the second grid lines 212), and there are no heterogeneous grid lines with bending sections. In this way, it is beneficial to reduce the total number of grid lines with bending sections in the electrode structure 20a, and then it is beneficial to reduce the problem of easy disconnection at the bending section when printing to form the grid lines 21, and finally it is beneficial to improve the yield rate of the solar cell.

[0096] The number of second grid lines 212 connected to the side of the second end pad P2 facing the first edge E1 is greater than the number of first grid lines 211 corresponding to the side of the second end pad P2 facing the first edge E1. In this way, in the first direction D1, there are opposite grid lines connected on the opposite sides of the second end pad P2, which realizes the effective collection of opposite carriers, is conducive to reducing the dead zone on the solar cell, and reduces the loss of solar cell performance.

[0097] The first grid line 211 between the second end pad P2 and the third edge E3 only extends along the first direction D1. In this way, all the anisotropic grid lines (i.e., the first grid lines 211) between the second end pad P2 and the third edge E3 do not have a bending section. In this way, it is beneficial to reduce the total number of grid lines with a bending section in the electrode structure 20a, and further to reduce the problem of easy disconnection at the bending section when the grid line 21 is printed, which is ultimately beneficial to improve the yield of the solar cell.

[0098] Along the second direction D2, between the third edge E3 and the second end pad P2, the gate line 21 closest to the second end pad P2 is the first gate line 211. Since the gate line 21 closest to the second end pad P2 between the third edge E3 and the second end pad P2 is a gate line with the same polarity as the second end pad P2, rather than a gate line with an opposite polarity to the second end pad P2, it is helpful to avoid the risk of short circuit at the end of the solder strip.

[0099] The arrangement rule of the plurality of grid lines 21 on the side of the second end pad P2 facing the first edge E1 is: a first grid line 211 and a second grid line 212 are alternately distributed. Between the fourth edge E4 and the second end pad P2, the grid line 21 closest to the second end pad P2 is also the first grid line 211. In this way, the number of the second grid lines 212 connected to the side of the second end pad P2 facing the first edge E1 is greater than the number of the first grid lines 211 corresponding to the side of the second end pad P2 facing the first edge E1. Since the grid lines 21 connected to the side of the second end pad P2 facing the second edge E2 are all second grid lines 212, therefore, in the first direction D1, there are opposite grid lines docking on the opposite sides of the second end pad P2, which realizes the effective collection of opposite carriers, which is conducive to reducing the dead zone on the solar cell and reducing the loss of solar cell performance.

[0100] A second gate line 212 that is closest to the third edge E3 among all the second gate lines 212 connected to the second end pad P2 on one side toward the first edge E1 is defined as a termination second gate line 212a. A first gate line 211 that is closest to the termination second gate line 212a on one side toward the third edge E3 is defined as a first gate line 211b that is adjacent to the first gate line. Along the second direction D2, the projection of the first gate line 211b and the second end pad P2 does not overlap. In other words, the first gate line 211b that is adjacent to the second end pad P2 does not extend between the second end pad P2 and the third edge E3. In this way, in the positive direction along the second direction D2, the gate line 21 that is adjacent to the second end pad P2 is a homosexual gate line, which is conducive to avoiding the risk of short circuit at the end of the solder strip.

[0101] The electrode structure 20 a further includes a second side grid 26 . The second side grid 26 is adjacent to the second edge E2 , extends along the second direction D2 , and is connected to at least a portion of the second gate line 212 .

[0102] Specifically, the second side grid 26 extends along the second edge E2 to be adjacent to the blank area B. Among them, part of the second grid line 212 between the second end pad P2 and the third edge E3, and part of the second grid line 212 between the second end pad P2 and the blank area B are connected to the second side grid 26. In this way, it is conducive to the collection of carriers of the solar cell in the area close to the first edge E1. In addition, the second grid line 212 connected to the second end pad P2 is also connected to the second side grid 26 to increase the reliability of carrier transmission and avoid the risk of the second end pad P2 bus failure after the second bus line 27 is broken.

[0103] The electrode structure 20a further includes a second bus line 27. The opposite ends of the second bus line 27 are respectively connected to the second side grid 26 and the second end pad P2, and the width of the second bus line 27 is greater than the width of the grid line 21. The larger the width of the second bus line 27, the smaller its resistance when transmitting carriers, which is more conducive to the transmission of current.

[0104] Along the second direction D2, the width of the second side grid 26 in the first direction D1 increases first and then decreases. The position where the second side grid 26 is connected to the second bus line 27 is the widest. Specifically, the position where the second side grid 26 is connected to the second bus line 27 is the widest, so that the resistance of the second side grid 26 at the position corresponding to the second bus line 27 is the smallest, which is conducive to ensuring the bus effect at the position of the second bus line 27. In addition, along the second direction D2, the width of the second side grid 26 in the first direction D1 increases first and then decreases, so that the line width of the second side grid 26 set at the position with a smaller bus effect is smaller, which is conducive to reducing the use of materials (such as silver paste) of the second side grid 26, thereby reducing production costs.

[0105] In the negative direction of the second direction D2, after the second side grid 26 is connected to the second bus line 27, the width of the second side grid 26 decreases suddenly. That is, with the second bus line 27 as the boundary, the reduction degree of the portion of the second side grid 26 located between the second bus line 27 and the fourth edge E4 is greater than the reduction degree of the portion of the second side grid 26 located between the second bus line 27 and the third edge E3. In this way, the use of materials (such as silver paste) of the second side grid 26 can be better reduced while ensuring the bus effect, thereby reducing the production cost.

[0106] The second busbar 27 is co-linear with the second grid line 212. Each second grid line 212 connected to the second end pad P2 in the negative direction of the first direction D1 is co-linear with a corresponding second grid line 212 in the positive direction of the second end pad P2 in the first direction D1. In this way, it is beneficial to improve the fault tolerance rate in the preparation process of the grid line 21, reduce the complexity of the processing, and make the stress of the edge area of ​​the solar cell more uniform, which is beneficial to reduce the probability of the solar cell breaking.

[0107] Along the second direction D2, there is a second gate line 212 connected to the second end pad P2 on opposite sides of the second bus line 27. More specifically, along the second direction D2, the two second gate lines 212 connected to the second end pad P2 on opposite sides of the second bus line 27 are symmetrically distributed about the second bus line 27. In this way, the electrode structure 20a has a beautiful appearance, and the second end pad P2 is more balanced in collecting carriers.

[0108] In some embodiments, the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 is equal to the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3. In this way, in the process of welding solar cells to form a battery string, it is beneficial to standardize the welding process.

[0109] In some embodiments, the center line of the first end pad P1 is aligned with the center line of the second end pad P2, so that along the first direction D1, the opposite sides of the first end pad P1 are aligned with the gate lines of opposite polarities, and the opposite sides of the second end pad P2 are aligned with the gate lines of the same polarity. In this way, compared with staggering the first end pad P1 and the second end pad P2, it is helpful to simplify the layout of the gate lines.

[0110] In other embodiments, the distance between any two adjacent first gate lines 211 is Z, and the difference between the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 and the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3 is less than 0.5Z. The smaller the difference in distance between the end pad and the third edge E3, the more conducive it is to the debugging of the welding equipment, the easier it is to weld, and the more beautiful the product is, especially controlling it within the range of 0.5Z can better ensure the accuracy and consistency of welding.

[0111] In addition, due to the influence of the welding machine itself, the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 is less than or equal to 10 mm, and the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3 is less than or equal to 10 mm.

[0112] During the process of welding to form a battery string, the end of the welding ribbon easily pierces the insulating adhesive layer and overlaps the opposite grid line. Figure 2 If the second gate line 212 between two adjacent first gate lines 211a is not interrupted, the distance between it and the edge of the first end pad P1 close to the third edge E3 is less than half the gate line spacing Z, so the risk of the end of the soldering tape piercing the insulating glue layer and causing a short circuit is relatively high. Figure 2 By making the second gate line 212 adjacent to the first end pad P1 avoid the lap wire 22, the risk of the end of the solder strip piercing the insulating adhesive layer and causing a short circuit is reduced. The provision of the bent section 2122 is conducive to improving the collection of carriers with opposite polarity to the first end pad P1 at the accommodating area C.

[0113] also, Figure 3In the positive direction along the second direction D2, the distance between the top of the second end pad P2 close to the third edge E3 and the opposite-sex gate line closest to the second end pad P2 is greater than a gate line spacing Z, which basically meets the distance required to prevent the end of the welding strip from piercing the insulating adhesive layer. Therefore, the risk of the end of the welding strip piercing the insulating adhesive layer and causing a short circuit is low. Therefore, Figure 3 In the embodiment, no heterogeneous grid lines with a bending section are arranged near the second end pad P2. In this way, the number of grid lines with a bending section in the electrode structure 20a is reduced, which is beneficial to reducing the problem of easy wire breakage at the bending section when the grid lines 21 are printed, and ultimately helps to improve the yield of the solar cell.

[0114] The present application embodiment also provides another electrode structure 20c. Figure 1 The electrode pattern in the middle electrode region A1 and / or the electrode pattern in the electrode region A2 may be the electrode structure 20c.

[0115] The following combination Figure 4 and Figure 5 The specific structure of the electrode structure 20c will be described.

[0116] like Figure 4 As shown, the electrode structure 20c includes a plurality of gate lines 21. Specifically, the gate lines 21 include a plurality of first gate lines 211 and a plurality of second gate lines 212. At least part of the first gate lines 211 and at least part of the second gate lines 212 are alternately distributed along the second direction D2. The first gate lines 211 and the second gate lines 212 have opposite polarities. For example, the first gate line 211 is a positive gate line, and the second gate line 212 is a negative gate line; or the first gate line 211 is a negative gate line, and the second gate line 212 is a positive gate line.

[0117] To make it clear, Figure 4 and Figure 5 In the figure, the first gate lines 211 are drawn with solid lines, and the second gate lines 212 are 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 gate lines 211 and the second gate lines 212.

[0118] The electrode structure 20 c further includes a first end pad P1 . The first end pad P1 is at least one pad closest to the third edge E3 among all pads adjacent to the first edge E1 . The first end pad P1 is electrically connected to a portion of the first gate line 211 .

[0119] Similar to the electrode structure 20a, in the electrode structure 20c, the gate lines 21 connected to the side of the first end pad P1 toward the first edge E1 are all first gate lines 211. That is, the gate lines 21 connected to the side of the first end pad P1 toward the first edge E1 are all homogeneous gate lines, and there are no heterogeneous gate lines with bending sections. In this way, it is beneficial to reduce the total number of gate lines with bending sections in the electrode structure 20a, and further to reduce the problem of easy disconnection at the bending section when the gate lines 21 are printed, which is ultimately beneficial to improve the yield of the solar cell.

[0120] Similar to the electrode structure 20a, in the electrode structure 20c, in the first direction D1, the number of opposite-sex grid lines on the opposite sides of the first end pad P1 is different, so that in the first direction D1, there are opposite-sex grid lines docking on the opposite sides of the first end pad P1, which realizes the effective collection of opposite-sex carriers, is beneficial to reducing the dead zone on the solar cell, and reducing the loss of solar cell performance.

[0121] Different from the electrode structure 20a, in the electrode structure 20c, the number of first gate lines 211 connected to the side of the first end pad P1 facing the second edge E2 is greater than the number of second gate lines 212 corresponding to the side of the first end pad P1 facing the second edge E2.

[0122] In this embodiment, the size of the first end pad P1 along the second direction D2 is greater than one gate line spacing and less than two gate line spacings, the number of first gate lines 211 connected to the side of the first end pad P1 facing the second edge E2 is two, and the number of second gate lines 212 corresponding to the side of the first end pad P1 facing the second edge E2 is one. In other embodiments, the size of the first end pad P1 along the second direction D2, the number of first gate lines 211 connected to the side of the first end pad P1 facing the second edge E2, and the number of second gate lines 212 corresponding to the side of the first end pad P1 facing the second edge E2 are not limited to the above.

[0123] The electrode structure 20c further includes a bonding wire 22. The bonding wire 22 is connected to the first end pad P1, extends toward the third edge E3 and is connected to the adjacent first gate line 211a. The adjacent first gate line 211a is at least one first gate line 211 adjacent to the first end pad P1 and connected to the bonding wire 22.

[0124] In this embodiment, the number of the adjacent first gate lines 211 a is one. In other embodiments, the number of the adjacent first gate lines 211 a is not limited thereto.

[0125] In this embodiment, the width of the bonding wire 22 is greater than the width of the first gate line 211. This helps to reduce the difficulty of bonding the bonding wire 22 to the pad, improve the fault tolerance during the preparation of the electrode structure 20c, and improve the current collection capacity of the bonding wire 22.

[0126] In this embodiment, the number of the lap line 22 is one. In other embodiments, the number of the lap line 22 is not limited thereto.

[0127] In this embodiment, the lap wire 22 extends from the first end pad P1 connected thereto beyond the adjacent first grid line 211a connected thereto. In the process of welding solar cells to obtain a cell string, the end of the conductive interconnect (such as a soldering strip) may bend unsteadily at the sharp corners due to cutting, which may pierce the insulating glue and cause a short circuit risk.

[0128] In this embodiment, the jumper line 22 extends from the first end pad P1 to at least one side of the third edge E3 beyond a gate line spacing Z, and at the position corresponding to the jumper line 22, the opposite gate line (i.e., the second gate line 212) is interrupted to avoid the jumper line 22, which can effectively avoid the risk of short circuit at the end of the solder strip.

[0129] In addition, to further avoid the risk of short circuit at the end of the solder strip, the end of the lap wire 22 extends beyond the adjacent first grid line 211a connected thereto by a certain reserved amount. The reserved amount is mainly affected by the accuracy of the string soldering machine. In some embodiments, the reserved amount is less than or equal to 0.2 mm.

[0130] In some embodiments, the lap wire 22 and the first end pad P1 are integrally formed, and the integral forming here may mean that the lap wire 22 and the first end pad P1 are printed together, and the two are integrally formed, which is convenient for processing, and has high electrical connection reliability and high production efficiency. In this case, the lap wire 22 and the first end pad P1 are made of the same material. In addition, the lap wire 22 and the first end pad P1 are integrally formed, which can also avoid the problem that the lap wire 22 and the first end pad P1 cannot be effectively electrically connected due to processing errors caused by forming the lap wire 22 and the first end pad P1 in batches.

[0131] In this embodiment, the lap wire 22, the adjacent first grid line 211a, and the first grid line 211 connected to the first end pad P1 and located between the first end pad P1 and the first edge E1 form a receiving area C on the surface of the battery substrate 10. A second grid line 212 adjacent to the adjacent first grid line 211a includes a main section 2121 extending along the first direction D1 and a bent section 2122 connected to the main section 2121 and bent into the receiving area C. In this way, by setting the bent section 2122, carriers with different polarities from the first end pad P1 in the receiving area C can be effectively collected, further reducing the performance loss of the solar cell.

[0132] In addition, there is a gap between the adjacent first grid line 211a and the first edge E1, and the bent section 2122 has a portion located in the gap and extending along the second direction D2. In this way, the bent section 2122 includes both a portion located in the accommodating area C and extending along the first direction D1, and a portion located in the gap and extending along the second direction D2, that is, the bent section 2122 is distributed in more directions, thereby increasing the coverage area of ​​the second grid line 212 on the battery substrate 10, thereby improving the collection capacity of carriers with different polarities of the first end pad P1.

[0133] The distance between any two adjacent first grid lines 211 is Z. Along the second direction D2, the length of the lap line 22 is L, and the integer part of the ratio of L to Z is N, where N is equal to the number of bent segments 2122 between the first end pad P1 connected to the lap line 22 and the nearest battery edge E. Under this configuration condition, it can be ensured that there is a bent segment in each of the different sub-areas of the accommodating area divided by the first grid lines 211 to collect opposite-sex carriers, which can effectively improve the battery efficiency.

[0134] In this embodiment, one second gate line 212 adjacent to the adjacent first gate line 211a is provided with a bending section 2122. In other embodiments, two or more second gate lines 212 adjacent to the adjacent first gate line 211a have a bending section 2122.

[0135] In this embodiment, the number of the bending segments 2122 in a second gate line 212 adjacent to the first gate line 211a is one. In other embodiments, in the second gate line 212 having the bending segments 2122, the number of the bending segments 2122 is not limited thereto, for example, it can be two or more than two.

[0136] In this embodiment, between the fourth edge E4 and the first end pad P1, the gate line 21 that is closest to the first end pad P1 is the second gate line 212. A first gate line 211 that is closest to the third edge E3 among all the first gate lines 211 connected to the first end pad P1 on one side toward the second edge E2 is defined as a termination first gate line 211c. A second gate line 212 that is closest to the side of the termination first gate line 211c toward the third edge E3 is defined as a second gate line 212c that is adjacent to the end of the second gate line 212c and the end of the bending section 2122 corresponding thereto is 1.5 to 2 times (such as 1.5 times, 1.6 times, 1.7 times, 1.8 times, 1.9 times, 2 times, etc.) of the length g of the first end pad P1 along the first direction D1.

[0137] Specifically, if the multiple of the distance G and the length g is greater than 2 times the upper limit, it is not conducive to the effective collection of carriers that are anisotropic with the first end pad P1; and if the multiple of the distance G and the length g is less than 1.5 times the lower limit, there is a risk of short circuit due to the small distance between the second gate line 212 and the bonding line 22.

[0138] In addition, the arrangement rule of the plurality of grid lines 21 on the side of the first end pad P1 facing the second edge E2 is: a first grid line 211 and a second grid line 212 are alternately distributed. Since the grid lines 21 adjacent to the first end pad P1 along the second direction D2 are all second grid lines 212, the number of first grid lines 211 connected to the side of the first end pad P1 facing the second edge E2 is greater than the number of second grid lines 212 corresponding to the side of the first end pad P1 facing the second edge E2, and since the grid lines 21 connected to the side of the first end pad P1 facing the first edge E1 are all first grid lines 211, therefore, in the first direction D1, there are opposite grid lines docking on the opposite sides of the first end pad P1, which realizes the effective collection of opposite carriers, which is conducive to reducing the dead zone on the solar cell and reducing the loss of solar cell performance.

[0139] The electrode structure 20 c further includes a first side grid 24 . The first side grid 24 is adjacent to the first edge E1 , substantially extends along the second direction D2 , and is connected to at least a portion of the first grid line 211 .

[0140] The difference from the electrode structure 20a is that in the electrode structure 20c, the first side grid 24 extends along the first edge E1 to a position substantially equivalent to the first end pad P1. In the electrode structure 20c, a portion of the first gate line 211 between the first end pad P1 and the third edge E3 is connected; while a portion of the first gate line 211 between the first end pad P1 and the blank area B is not connected to the first side grid 24.

[0141] The electrode structure 20c further includes a first bus line 25. The opposite ends of the first bus line 25 are respectively connected to the first side grid 24 and the first end pad P1. The width of the first bus line 25 is greater than the width of the grid line 21. The larger the width of the first bus line 25, the smaller the resistance when transmitting carriers, which is more conducive to the transmission of current.

[0142] The difference from the electrode structure 20a is that the width of the first side grid 24 in the first direction D1 gradually increases along the second direction D2. The first side grid 24 is connected to the first bus line 25 at a wider position to balance the material cost of the first side grid 24 and the bus effect of the first side grid 24.

[0143] In this embodiment, the first busbar 25 is colinear with a first grid line 211. Each first grid line 211 connected to the first end pad P1 in the positive direction of the first direction D1 is colinear with a corresponding second grid line 212 in the negative direction of the first end pad P1 in the first direction D1. In this way, it is beneficial to improve the fault tolerance rate in the preparation process of the grid line 21, reduce the complexity of the processing, and make the stress of the edge area of ​​the solar cell more uniform, which is beneficial to reduce the probability of the solar cell breaking.

[0144] Along the second direction D2, there is a first gate line 211 connected to the first end pad P1 on opposite sides of the first bus line 25. More specifically, the two first gate lines 211 connected to the first end pad P1 on opposite sides of the first bus line 25 along the second direction D2 are symmetrically distributed about the first bus line 25. In this way, the electrode structure 20a has a beautiful appearance, and the first end pad P1 is more balanced in collecting carriers.

[0145] The first gate line 211 between the first end pad P1 and the first edge E1 is also connected to the first side gate 24 to increase the reliability of carrier transmission and avoid the risk of bus failure of the first end pad P1 after the first bus line 25 is broken.

[0146] like Figure 5 As shown, the electrode structure 20c further includes a second end pad P2. The second end pad P2 is at least one pad closest to the third edge E3 among all pads adjacent to the second edge E2. The second end pad P2 is electrically connected to a portion of the second gate line 212.

[0147] Similar to the electrode structure 20a, in the electrode structure 20c, the gate lines 21 connected to the side of the second end pad P2 toward the second edge E2 are all second gate lines 212. That is, the gate lines 21 connected to the side of the second end pad P2 toward the second edge E2 are all the same-sex gate lines (i.e., the second gate lines 212), and there are no heterogeneous gate lines with bending sections. In this way, it is beneficial to reduce the total number of gate lines with bending sections in the electrode structure 20c, and further to reduce the problem of easy disconnection at the bending section when the gate lines 21 are printed, which is ultimately beneficial to improve the yield of the solar cell.

[0148] Similar to the electrode structure 20a, in the electrode structure 20c, in the first direction D1, the number of opposite-sex grid lines on the two opposite sides of the second end pad P2 is different, so that in the first direction D1, there are opposite-sex grid lines docking on the two opposite sides of the second end pad P2, which is beneficial to reducing the dead zone on the solar cell, so that the opposite-sex carriers can be collected more effectively, reducing the loss of solar cell performance. The difference from the electrode structure 20a is that in the electrode structure 20c, the number of second grid lines 212 connected to the side of the second end pad P2 facing the first edge E1 is less than the number of first grid lines 211 corresponding to the side of the second end pad P2 facing the first edge E1.

[0149] Similar to the structure of the electrode structure 20a, in the electrode structure 20c, the first grid line 211 between the second end pad P2 and the third edge E3 only extends along the first direction D1. In this way, all the anisotropic grid lines (i.e., the first grid lines 211) between the second end pad P2 and the third edge E3 do not have a bending section. In this way, it is beneficial to reduce the total number of grid lines with a bending section in the electrode structure 20c, and further to reduce the problem of easy disconnection at the bending section when the grid line 21 is printed, which is ultimately beneficial to improve the yield of the solar cell.

[0150] Along the second direction D2, between the third edge E3 and the second end pad P2, and between the fourth edge E4 and the second end pad P2, the gate line 21 closest to the second end pad P2 is the second gate line 212. Since in the positive direction along the second direction D2, the gate line 21 closest to the second end pad P2 is the gate line with the same polarity as the second end pad P2, it is helpful to avoid the risk of short circuit at the end of the solder strip.

[0151] In addition, since the arrangement pattern of the multiple grid lines 21 on the side of the second end pad P2 facing the first edge E1 is that a first grid line 211 and a second grid line 212 are alternately distributed, and by setting the grid lines 21 closest to the second end pad P2 along the second direction D2 as the second grid lines 212, there are opposite grid lines docking on the opposite sides of the second end pad P2 in the first direction D1, which is beneficial to reducing the dead zone on the solar cell, so that the opposite carriers can be collected more effectively, reducing the loss of solar cell performance.

[0152] The electrode structure 20 c further includes a second side grid 26 . The second side grid 26 is adjacent to the second edge E2 , substantially extends along the second direction D2 , and is connected to at least a portion of the second gate line 212 .

[0153] The difference from the electrode structure 20a is that in the electrode structure 20c, the second side grid 26 extends along the second edge E2 to a position roughly equivalent to the second end pad P2. In the electrode structure 20c, part of the second grid line 212 between the second end pad P2 and the third edge E3 is connected; while part of the second grid line 212 between the second end pad P2 and the blank area B is not connected to the second side grid 26. Similar to the electrode structure 20a, in the electrode structure 20c, the second grid line 212 connected to the second end pad P2 is also connected to the second side grid 26 to increase the reliability of carrier transmission and avoid the risk of bus failure of the second end pad P2 after the second bus line 27 is broken.

[0154] The electrode structure 20c further includes a second bus line 27. The opposite ends of the second bus line 27 are respectively connected to the second side grid 26 and the second end pad P2, and the width of the second bus line 27 is greater than the width of the grid line 21. The larger the width of the second bus line 27, the smaller the resistance when transmitting carriers, which is more conducive to the transmission of current.

[0155] The difference from the electrode structure 20a is that the width of the second side grid 26 in the first direction D1 gradually increases along the second direction D2. The second side grid 26 is connected to the second bus line 27 at a wider position to balance the material cost and the bus effect of the second side grid 26.

[0156] The second busbar 27 is co-linear with a second grid line 212. Each second grid line 212 connected to the second end pad P2 in the positive direction of the first direction D1 is co-linear with a corresponding first grid line 211 in the negative direction of the second end pad P2 in the first direction D1. In this way, it is beneficial to improve the fault tolerance rate in the preparation process of the grid line 21, reduce the complexity of the processing, and make the stress of the edge area of ​​the solar cell more uniform, which is beneficial to reduce the probability of the solar cell breaking.

[0157] Along the second direction D2, there is a second gate line 212 connected to the second end pad P2 on opposite sides of the second bus line 27. More specifically, the two second gate lines 212 connected to the second end pad P2 on opposite sides of the second bus line 27 along the second direction D2 are symmetrically distributed about the second bus line 27. In this way, the electrode structure 20c has a beautiful appearance, and the second end pad P2 is more balanced in collecting carriers.

[0158] In some embodiments, the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 is equal to the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3. In this way, in the process of welding solar cells to form a battery string, it is beneficial to standardize the welding process.

[0159] In some embodiments, the center line of the first end pad P1 is aligned with the center line of the second end pad P2, so that along the first direction D1, the gate lines of the same polarity are aligned on opposite sides of the first end pad P1, and the gate lines of the opposite polarity are aligned on opposite sides of the second end pad P2. In this way, compared with staggering the first end pad P1 and the second end pad P2, it is helpful to simplify the layout of the gate lines.

[0160] In other embodiments, the distance between any two adjacent first gate lines 211 is Z, and the difference between the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 and the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3 is less than 0.5Z. The smaller the difference in distance between the end pad and the third edge E3, the more conducive it is to the debugging of the welding equipment, the easier it is to weld, and the more beautiful the product is, especially controlling it within the range of 0.5Z can better ensure the accuracy and consistency of welding.

[0161] In addition, due to the influence of the welding machine itself, the distance from the side of the first end pad P1 close to the third edge E3 to the third edge E3 is less than or equal to 10 mm, and the distance from the side of the second end pad P2 close to the third edge E3 to the third edge E3 is less than or equal to 10 mm.

[0162] Similar to the electrode structure 20a: in the process of welding to form a battery string, the end of the welding strip easily pierces the insulating adhesive layer and overlaps the grid line of the opposite sex. Figure 4 If the second gate line 212c is not interrupted, the distance between it and the edge of the first end pad P1 close to the third edge E3 is less than half the gate line spacing Z, so the risk of the end of the solder strip piercing the insulating glue layer and causing a short circuit is relatively high. Figure 4By avoiding the lap wire 22 adjacent to the second gate line 212c, the risk of the end of the solder strip piercing the insulating adhesive layer and causing a short circuit is reduced. The provision of the bent section 2122 is conducive to improving the collection of carriers with opposite polarity to the first end pad P1 at the accommodating area C.

[0163] also, Figure 5 Since the distance between the top of the second end pad P2 close to the third edge E3 and the opposite-sex gate line closest to the second end pad P2 in the positive direction of the second direction D2 is greater than half the gate line spacing (approximately one gate line spacing Z), it basically meets the distance required to avoid the end of the welding strip piercing the insulating adhesive layer. Therefore, the risk of the end of the welding strip piercing the insulating adhesive layer and causing a short circuit is low. Therefore, Figure 5 In the embodiment, no heterogeneous grid lines with a bending section are arranged near the second end pad P2. In this way, the number of grid lines with a bending section in the electrode structure 20c is reduced, which is beneficial to reducing the problem of easy wire breakage at the bending section when the grid lines 21 are printed, and ultimately helps to improve the yield of the solar cell.

[0164] Figure 6 FIG. 1 is a schematic plan view of a solar cell according to a second embodiment of the present application. Figure 6 As shown, the solar cell 200 includes a cell substrate 10' and an electrode region A1 (A2) located on the cell substrate 10'. The electrode structure on the electrode region A1 (A2) can be Figure 2 and Figure 3 The electrode structure 20a shown may also be Figure 4 and Figure 5 The electrode structure 20c shown in FIG.

[0165] In some embodiments, the solar cell 200 can be Figure 1 The solar cell 100 shown is cut into two equal parts.

[0166] In other embodiments, in the process of constructing a battery string, not only can the solar cell be divided into two equal parts to obtain a half-cell, but it can also be cut into three-cell, four-cell or eight-cell slices, etc. Each slice cell includes at least one first end pad and at least one second end pad. The embodiments of the present application do not limit the slice method used to construct the battery string and the specific specifications of the slice cells.

[0167] The present application also provides a solar panel. The solar panel includes at least two Figure 6 The solar cell 200 shown. A plurality of solar cells 200 in the solar module can be connected in series and / or in parallel via conductive interconnects (such as solder ribbons) to form a cell string.

[0168] The above implementation modes are only used to illustrate the technical solutions of the present application and are not intended to limit the present application. Although the present application has been described in detail with reference to the above preferred implementation modes, a person skilled in the art should understand that the technical solutions of the present application may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present application.

Claims

1. A solar cell, characterized in that: include: A battery substrate including a plurality of battery edges, the plurality of battery edges including a first edge and a second edge opposite to each other in a first direction and a third edge and a fourth edge opposite to each other in a second direction, the second direction intersecting the first direction; An electrode structure, located on the battery substrate, comprising: A plurality of gate lines, including first gate lines and second gate lines with opposite polarities, at least part of the first gate lines and at least part of the second gate lines are alternately distributed along the second direction; A first end pad, which is at least one pad closest to the third edge among all pads adjacent to the first edge, and is electrically connected to a portion of the first gate line; A second end pad, which is at least one pad closest to the third edge among all pads adjacent to the second edge, and is electrically connected to a portion of the second gate line; as well as A overlap line, after being connected to the first end pad, extends toward the third edge and overlaps with an adjacent first gate line, the adjacent first gate line being at least one of the first gate lines adjacent to the first end pad and connected to the overlap line; the overlap line and the adjacent first gate line or the overlap line and the adjacent first gate line and the first gate line connected to the first end pad and located between the first end pad and the first edge form a receiving area on the surface of the battery substrate, at least one of the second gate lines adjacent to the adjacent first gate line includes a main section extending along the first direction and at least one bending section connecting the main section and bending into the receiving area; the first gate line between the second end pad and the third edge only extends along the first direction.

2. The solar cell according to claim 1, wherein: The gate lines connected to the side of the first end pad facing the first edge are all the first gate lines; and / or, The gate lines connected to the side of the second end pad facing the second edge are all the second gate lines.

3. The solar cell according to claim 1, wherein: The number of the first gate lines connected to the side of the first end pad facing the second edge is less than the number of the second gate lines corresponding to the side of the first end pad facing the second edge; The number of the second gate lines connected to the side of the second end pad facing the first edge is greater than the number of the first gate lines corresponding to the side of the second end pad facing the first edge.

4. The solar cell according to claim 3, characterized in that The gate lines between the third edge and the first end pad, and between the fourth edge and the first end pad, which are closest to the first end pad, are all the first gate lines; The gate line between the fourth edge and the second end pad and the closest to the second end pad is the first gate line; defining a second gate line closest to the third edge among all the second gate lines connected to the side of the second end pad facing the first edge as a terminating second gate line; defining a first gate line that is most adjacent to a side of the terminated second gate line facing the third edge as an adjacent first gate line; Along the second direction, projections of the immediately adjacent first gate line and the second end pad do not overlap.

5. The solar cell according to claim 1, wherein: The number of the first gate lines connected to the side of the first end pad facing the second edge is greater than the number of the second gate lines corresponding to the side of the first end pad facing the second edge; The number of the second gate lines connected to the side of the second end pad facing the first edge is less than the number of the first gate lines corresponding to the side of the second end pad facing the first edge.

6. The solar cell according to claim 5, characterized in that The gate lines between the third edge and the second end pad, and between the fourth edge and the second end pad, which are closest to the second end pad, are all the second gate lines; The gate line between the fourth edge and the first end pad and the closest to the first end pad is the second gate line; defining a first gate line closest to the third edge among all the first gate lines connected to the first end pad on the side facing the second edge as a terminating first gate line; defining a second gate line that is most adjacent to a side of the terminated first gate line facing the third edge as an adjacent second gate line; The distance between the end portion adjacent to the second gate line and the end portion of the bending section corresponding thereto is 1.5 to 2 times the length of the first end pad along the first direction.

7. The solar cell according to claim 1, wherein: The distance between any two adjacent first grid lines is Z, and along the second direction, the length of the overlap line is L, the integer part of the ratio of L and Z is N, and N is equal to the number of bending sections between the first end pad connected by the overlap line and the nearest battery edge.

8. The solar cell according to claim 1, wherein: The distance from the side of the first end pad close to the third edge to the third edge is equal to the distance from the side of the second end pad close to the third edge to the third edge, or, the distance between any two adjacent first gate lines is Z, and the difference between the distance from the side of the first end pad close to the third edge to the third edge and the distance from the side of the second end pad close to the third edge to the third edge is less than 0.5Z.

9. The solar cell according to claim 1, wherein: The width of the lap wire is the same as that of the first gate line, there are at least two lap wires, and each lap wire extends from the adjacent first gate line electrically connected thereto to the inside of the first end pad; or, The width of the bonding line is greater than the width of the first gate line, and the bonding line extends from the first end pad connected thereto and beyond the first gate line connected thereto.

10. The solar cell according to claim 1, wherein: The bonding wire is connected to at least one of the first gate lines located between the first edge and the first end pad.

11. The solar cell according to any one of claims 1 to 10, characterized in that: The electrode structure further includes a first side grid, which is adjacent to the first edge, extends along the second direction, and is connected to at least part of the first grid line; and / or, The electrode structure further includes a second side grid, which is adjacent to the second edge, extends along the second direction, and is connected to at least a portion of the second grid line.

12. The solar cell according to claim 11, wherein: The electrode structure further includes a first bus line, opposite ends of which are respectively connected to the first side grid and the first end pad, and a width of the first bus line is greater than a width of the grid line; and / or, The electrode structure further includes a second bus line, opposite ends of which are respectively connected to the second side grid and the second end pad, and a width of the second bus line is greater than a width of the grid line.

13. The solar cell according to claim 12, wherein: The first side grid, and / or the second side grid, has a width increasing in the first direction along the second direction; or, The width of the first side grid and / or the second side grid in the first direction along the second direction first increases and then decreases, the first side grid is widest at the position where it connects to the first bus bar, and the second side grid is widest at the position where it connects to the second bus bar.

14. A solar panel, characterized in that: Comprising at least two solar cells according to any one of claims 1 to 13.

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