Solar cell and subgrid printing screen

Abstract

This application provides a solar cell and a sub-gate printing screen, relating to the field of energy technology. The solar cell includes a silicon wafer and an electrode structure. The electrode structure includes a main gate and a first sub-gate. The main gate includes a main gate line and a plurality of first pads, the main gate line extending along a first direction and connecting any two adjacent first pads. The first sub-gate includes a first sub-gate line and a first extension, the first extension being connected to one side of the first sub-gate line along a second direction and used to overlap with the first pads. The first pad includes a first edge and a second edge, the first and second edges extending along the second direction and arranged opposite to each other along the first direction. In the first direction, the second edge is farther away from the first edge relative to the first edge of the first sub-gate. The end of the first extension away from the first sub-gate line extends towards the second edge. The embodiments of this application can reduce the overprinting difficulty of the sub-gate and the main gate, improve the overlap reliability of the two, and reduce the risk of disconnection between the sub-gate and the main gate.

Description

Technical Field

[0001] This application relates to the field of energy technology, and more particularly to a solar cell and a subgrid printing screen. Background Technology

[0002] A solar cell may include a silicon wafer and an electrode structure, which may be disposed on the light-receiving side or the back-lighting side of the silicon wafer. The electrode structure includes a main grid and a sub-grid, which are overlapped.

[0003] Typically, the main gate and the sub-gate are printed on the silicon wafer in steps using different printing screens. For example, the main gate can be printed on the silicon wafer first, and then the sub-gate can be printed.

[0004] During the printing process, the registration of the sub-grid and the main grid is difficult, which affects the reliability of the overlap between the sub-grid and the main grid and increases the risk of disconnection between the sub-grid and the main grid. Utility Model Content

[0005] The embodiments of this application disclose a solar cell and a printing screen for a sub-grid, which can reduce the difficulty of overprinting the sub-grid and the main grid, improve the reliability of the overlap between the sub-grid and the main grid, and reduce the risk of disconnection between the sub-grid and the main grid.

[0006] To achieve the above objectives, one embodiment of this application provides a solar cell. The solar cell includes a silicon wafer and an electrode structure. The silicon wafer includes a light-receiving surface and a back-lighting surface. The electrode structure is disposed on either the light-receiving surface or the back-lighting surface. The electrode structure includes a main grid and a first sub-grid. The main grid includes a main grid line and a plurality of first pads, the plurality of first pads being spaced apart along a first direction, the main grid line extending along the first direction and connecting any two adjacent first pads. The first sub-grid includes a first sub-grid line and a first extension, the first sub-grid line extending along a second direction, the second direction being perpendicular to the first direction. The first extension is located on one side of the first sub-grid line along the second direction and connected to the first sub-grid line. The first extension is used to overlap with the first pad. The first pad includes a first edge and a second edge, the first edge and the second edge extending along the second direction, and the first edge and the second edge being disposed opposite each other along the first direction. In the first direction, the second edge is farther away from the first sub-grid relative to the first edge. The end of the first extension away from the first sub-grid line extends towards the second edge.

[0007] In some possible implementations, the end of the first extension furthest from the first sub-gate line is designated as the first end. There are multiple first sub-gates, including a first first sub-gate and a second first sub-gate, which are spaced apart along a second direction and overlap with the same first pad. In the second direction, the distance between the first end of the first extension of the first first sub-gate and the first end of the first extension of the second first sub-gate is a first distance, which is less than the width of the first pad in the second direction.

[0008] In some possible implementations, the end of the first extension connected to the first sub-gate line is designated as the second end. The first pad includes a third side and a fourth side, which extend along a first direction and are positioned opposite each other along a second direction. The first sub-gate line of the first first sub-gate intersects the third side, and in the second direction, the distance between the second end of the first extension of the first first sub-gate and the third side ranges from 0.05 mm to 0.15 mm. The first sub-gate line of the second first sub-gate intersects the fourth side, and in the second direction, the distance between the second end of the first extension of the second first sub-gate and the fourth side ranges from 0.05 mm to 0.15 mm.

[0009] In some possible implementations, the angle between the first extension and the first sub-gate line is an obtuse angle.

[0010] In some possible implementations, the angle between the first extension and the first sub-gate line ranges from 120° to 150°.

[0011] In some possible implementations, the length of the first extension ranges from 0.05 mm to 0.15 mm.

[0012] In some possible implementations, the first sub-gate further includes a first connecting portion. The first connecting portion connects the first sub-gate line and the first extension; alternatively, the first sub-gate line includes a first sub-segment and a second sub-segment spaced apart along a second direction, and the first connecting portion connects the first sub-segment and the second sub-segment. The width of the first connecting portion is greater than the width of the first sub-gate line and the first extension.

[0013] In some possible implementations, the main gate further includes a second pad located on one side of a plurality of first pads along a first direction, with the main gate line connecting the first and second pads. The electrode structure also includes multiple second sub-gates, each comprising a first and a second sub-gate, spaced apart along a second direction and overlapping with the same second pad. In the second direction, the distance between the end of the first sub-gate near the second sub-gate and the end of the second sub-gate near the first sub-gate is a second distance, which is less than the width of the second pad in the second direction.

[0014] In some possible implementations, the electrode structure further includes a harpoon portion, which includes a harpoon line and a second extension. The second extension is connected to the harpoon line, and there is an angle between the second extension and the harpoon line. The second extension is used to overlap with a second pad. At least a portion of the harpoon line is located on the side of the second pad away from the first pad and extends to the edge of the silicon wafer. The harpoon portion includes a first harpoon portion and a second harpoon portion spaced apart along a second direction. In the second direction, a first second sub-gate is located on the side of the first harpoon portion away from the second harpoon portion and is connected to the second extension of the first harpoon portion. In the second direction, a second second sub-gate is located on the side of the second harpoon portion away from the first harpoon portion and is connected to the second extension of the second harpoon portion.

[0015] In some possible implementations, the second pad includes a fifth side and a sixth side, which extend along a first direction and are disposed opposite each other along a second direction. The first second sub-gate intersects the fifth side, and in the second direction, the distance between the end of the first second sub-gate near the second sub-gate and the fifth side ranges from 0.05 mm to 0.15 mm. The second second sub-gate intersects the sixth side, and in the second direction, the distance between the end of the second second sub-gate near the first second sub-gate and the sixth side ranges from 0.05 mm to 0.15 mm.

[0016] In some possible implementations, the second sub-gate further includes a second sub-gate line and a second connecting portion. The second sub-gate line includes a third sub-segment and a fourth sub-segment spaced apart along a second direction, and the second connecting portion connects the third sub-segment and the fourth sub-segment. The width of the second connecting portion is greater than the width of the second sub-gate line.

[0017] On the other hand, embodiments of this application provide a sub-gate printing screen for printing sub-gates onto a silicon wafer on which a main gate is disposed. The main gate includes a main gate line and a plurality of first pads, the plurality of first pads being spaced apart along a first direction. The main gate line extends along the first direction and connects any two adjacent first pads. The sub-gate printing screen includes a screen body on which a first sub-gate pattern is formed. The first sub-gate pattern includes a first sub-gate line pattern and a first extension pattern. The first sub-gate line pattern extends along a second direction, which is perpendicular to the first direction. The first extension pattern is located on one side of the first sub-gate line pattern along the second direction and is connected to the first sub-gate line pattern. An angle exists between the first sub-gate line pattern and the first extension pattern.

[0018] In some possible implementations, the end of the first extension pattern furthest from the first sub-gate pattern is designated as the third end. There are multiple first sub-gate patterns, including a first sub-gate pattern and a second sub-gate pattern, which are spaced apart along a second direction. In the second direction, the distance between the third end of the first extension pattern of the first sub-gate pattern and the third end of the first extension pattern of the second sub-gate pattern is designated as a third distance, which is less than the width of the first pad in the second direction.

[0019] In some possible implementations, the angle between the first subgrid pattern and the first extension pattern is an obtuse angle.

[0020] In some possible implementations, the main gate further includes a second pad located on one side of a plurality of first pads along a first direction, and the main gate line connects the first pad and the second pad. A second sub-gate pattern is formed on the net body, and there are multiple second sub-gate patterns, including a first second sub-gate pattern and a second second sub-gate pattern, which are spaced apart along a second direction. In the second direction, the distance between the end of the first second sub-gate pattern near the end of the second second sub-gate pattern and the end of the second second sub-gate pattern near the end of the first second sub-gate pattern is a fourth distance, which is less than the width of the second pad in the second direction.

[0021] In some possible implementations, a harpoon pattern is formed on the mesh body. The harpoon pattern includes a harpoon line pattern and a second extension pattern, which are connected. The harpoon pattern includes a first harpoon pattern and a second harpoon pattern spaced apart along a second direction. In the second direction, a first second sub-gate pattern is located on the side of the first harpoon pattern away from the second harpoon pattern and is connected to the second extension pattern of the first harpoon pattern. In the second direction, a second second sub-gate pattern is located on the side of the second harpoon pattern away from the first harpoon pattern and is connected to the second extension pattern of the second harpoon pattern.

[0022] The embodiments of this application have at least the following beneficial effects:

[0023] In the embodiments of this application, the first sub-gate includes a first sub-gate line and a first extension. The end of the first extension away from the first sub-gate line extends toward the direction closer to the second side, so that the first extension can provide the first sub-gate line with an offset margin in a first direction.

[0024] During the overlay process of the first sub-gate and the main gate, if the first sub-gate line is offset relative to the main gate in the first direction, for example, when the first sub-gate line is offset to the side of the first side away from the second side, the end of the first extension away from the first sub-gate line extends towards the second side, so that the first extension can overlap with the first pad, that is, the first sub-gate can overlap with the first pad.

[0025] This configuration reduces the difficulty of overlaying the first sub-busbar and the main busbar, improves the reliability of the overlap between the first sub-busbar and the main busbar, reduces the risk of disconnection between the first sub-busbar and the main busbar, improves the reliability of the solar cell, and increases the production yield of the solar cell.

[0026] Understandably, the first sub-gate and the main gate have an offset margin during the overlay process. This eliminates the need for a connecting part or other structure at the first pad to connect the first sub-gate, reducing the amount of silver paste used and lowering the cost of the solar cell.

[0027] Furthermore, when the electrode structure is placed on the light-receiving surface, it can reduce the shading caused by the electrode structure on the light-receiving surface and improve the photoelectric conversion efficiency of the solar cell. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a schematic diagram of the structure of a solar cell provided in some embodiments of this application;

[0030] Figure 2 A schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for some embodiments of this application;

[0031] Figure 3 A schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for other embodiments of this application;

[0032] Figure 4 A schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for some embodiments of this application;

[0033] Figure 5 A schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for some embodiments of this application;

[0034] Figure 6 A schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for some embodiments of this application;

[0035] Figure 7 A schematic diagram showing the positional relationship between the second sub-gate and the second pad provided in some embodiments of this application;

[0036] Figure 8 A schematic diagram showing the positional relationship between the second sub-gate and the second pad provided for other embodiments of this application;

[0037] Figure 9 A schematic diagram showing the positional relationship between the second sub-gate and the second pad provided for some embodiments of this application;

[0038] Figure 10 A schematic diagram showing the positional relationship between the second sub-gate and the second pad provided for some embodiments of this application;

[0039] Figure 11 A schematic diagram showing the positional relationship between the second sub-gate and the second pad provided for some embodiments of this application;

[0040] Figure 12 This is a schematic diagram of the structure of a subgrid printing screen provided in some embodiments of this application;

[0041] Figure 13 This is a schematic diagram of the structure of a first grid pattern provided in some embodiments of this application;

[0042] Figure 14 A schematic diagram of the structure of the first grid pattern provided in some other embodiments of this application;

[0043] Figure 15 A schematic diagram of the structure of a first grid pattern provided for some embodiments of this application;

[0044] Figure 16 This is a schematic diagram of the structure of a second grid pattern provided in some embodiments of this application;

[0045] Figure 17 A schematic diagram of the structure of a second grid pattern provided for other embodiments of this application.

[0046] Explanation of reference numerals in the attached figures:

[0047] 100 - Solar cell, 110 - Silicon wafer, 1101 - Light-receiving surface, 1102 - Backlighting surface, 120 - Electrode structure, 130 - Main grid, 131 - Main grid line, 132 - First pad, 1321 - First side, 1322 - Second side, 1323 - Third side, 1324 - Fourth side, 133 - Second pad, 1331 - Fifth side, 1332 - Sixth side, 1333 - Seventh side, 1334 - Eighth side, 140 - First sub-grid, 140a - First sub-grid, 140b - Second sub-grid Grid, 141-First sub-grid line, 1411-First sub-segment, 1412-Second sub-segment, 142-First extension, 143-First connecting part, 150-Second sub-grid, 150a-First second sub-grid, 150b-Second second sub-grid, 151-Second sub-grid line, 1511-Third sub-segment, 1512-Fourth sub-segment, 152-Third extension, 153-Second connecting part, 160-Harpoon part, 160a-First harpoon part, 160b-Second harpoon part, 161-Harpoon line, 162 - Second extension, 170- Sub-grid, 200- Sub-grid printing screen, 201- Screen body, 210- First sub-grid pattern, 210a- First first sub-grid pattern, 210b- Second first sub-grid pattern, 211- First sub-grid line pattern, 2111- First sub-line segment pattern, 2112- Second sub-line segment pattern, 212- First extension pattern, 213- First connecting pattern, 220- Second sub-grid pattern, 220a- First second sub-grid pattern, 220b- Second second sub-grid pattern, 221- Second grid line pattern, 2211-Third sub-segment pattern, 2212-Fourth sub-segment pattern, 223-Second connecting part pattern, 230-Harpoon part pattern, 230a-First harpoon part pattern, 230b-Second harpoon part pattern, 231-Harpoon line pattern, 232-Second extension part pattern, 240-Second grid printing pattern, X-First direction, Y-Second direction, M1-First end, M2-Second end, M3-Third end, H1-First distance, H2-Second distance, H3-Third distance, H4-Fourth distance. Detailed Implementation

[0048] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0049] In this application, the terms "upper," "left," "right," "front," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. These terms are primarily for the purpose of better describing this application and its embodiments, and are not intended to limit the indicated device, element, or component to having a specific orientation, or to be constructed and operated in a specific orientation.

[0050] Furthermore, in addition to indicating location or positional relationship, some of the aforementioned terms may also have other meanings. For example, the term "above" may also be used in some cases to indicate a certain dependency or connection relationship. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0051] Furthermore, the terms "installation," "setup," "equipped with," and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral structure; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or an internal connection between two devices, components, or parts. Those skilled in the art can understand the specific meaning of these terms in this application based on the specific circumstances.

[0052] Furthermore, the terms "first," "second," etc., are primarily used to distinguish different devices, elements, or components (which may be the same or different in specific type and construction), and are not intended to indicate or imply the relative importance or quantity of the indicated devices, elements, or components. Unless otherwise stated, "a plurality of" means two or more.

[0053] Figure 1 The diagram shows the structure of a solar cell provided in some embodiments of this application. Figure 1 As shown, an embodiment of this application provides a solar cell 100, which, as can be understood, is capable of converting solar energy into electrical energy. Continuing to refer to... Figure 1 In some examples, the solar cell 100 includes a silicon wafer 110 and an electrode structure 120.

[0054] Silicon wafer 110 is used to convert solar energy into electrical energy. For example, silicon wafer 110 may include a P-type silicon wafer and an N-type semiconductor, which can form a PN junction. When sunlight shines on the PN junction, photon energy excites electrons to jump from the valence band to the conduction band, forming electron-hole pairs. These charge carriers (electron-hole pairs) separate under the influence of the built-in electric field of the PN junction; electrons are pushed into the N-region, and holes are pushed into the P-region, thereby generating an electromotive force and current, enabling silicon wafer 110 to convert solar energy into electrical energy. It is understood that silicon wafer 110 may also include other structures, and the embodiments of this application do not further limit the structure of silicon wafer 110.

[0055] like Figure 1 As shown, the silicon wafer 110 can be octagonal, or it can be quadrilateral, hexagonal, or other regular and irregular shapes. The embodiments of this application do not further limit the shape of the silicon wafer 110.

[0056] In some examples, silicon wafer 110 includes a light-receiving surface 1101 and a back-lighting surface 1102. Understandably, the light-receiving surface 1101 and the back-lighting surface 1102 are arranged opposite to each other, with the light-receiving surface 1101 receiving light and the back-lighting surface 1102 facing away from the light. Both the light-receiving surface 1101 and the back-lighting surface 1102 can be planar, or at least one of them can be curved.

[0057] In some examples, such as Figure 1 As shown, the electrode structure 120 is disposed on the light-receiving surface 1101 or the backlight surface 1102.

[0058] Understandably, when the electrode structure 120 is disposed on the light-receiving surface 1101, the structure of the solar cell 100 can be simplified. When the electrode structure 120 is disposed on the backlight surface 1102, the electrode structure 120 can be prevented from blocking the light-receiving surface 1101, thereby improving the photoelectric conversion efficiency of the solar cell 100. The embodiments of this application take the electrode structure 120 disposed on the light-receiving surface 1101 as an example for further illustration.

[0059] Continue to refer to Figure 1 In some examples, electrode structure 120 includes a main gate 130 and a sub-gate 170, which are overlapped.

[0060] There can be multiple main gates 130 and sub-gates 170. The number of main gates 130 and sub-gates 170 can be equal or unequal. For example, the number of main gates 130 can be less than the number of sub-gates 170.

[0061] like Figure 1 As shown, the main gate 130 can extend along a first direction X, and multiple main gates 130 can be spaced apart along a second direction Y. The sub-gates 170 can extend along the second direction Y, and multiple sub-gates 170 can be spaced apart along the first direction X and the second direction Y. For example, the sub-gates 170 are used to collect current generated at different locations on the silicon wafer 110, and the main gates 130 are used to collect the current collected by the multiple sub-gates 170.

[0062] In some examples, the second direction Y is perpendicular to the first direction X. Understandably, the second direction Y and the first direction X can be perpendicular or approximately perpendicular, that is, the angle between the second direction Y and the first direction X can be 90°, or it can be 89°, 88° or 87°, etc.

[0063] For example, the materials of the main gate 130 and the sub-gate 170 include silver paste to improve the conductivity of the main gate 130 and the sub-gate 170.

[0064] Currently, improving the performance of solar cells is one of the important directions in photovoltaic technology research. As solar cell technology continues to mature, cost is gradually becoming the primary issue to consider in optimizing solar cell processes and developing new technologies.

[0065] To optimize the cost of the solar cell 100, the main busbar 130 and the sub-busbar 170 are typically printed onto the silicon wafer 110 using silver pastes with different silver contents through a step-by-step printing process. Generally, the silver content of the silver paste used to prepare the sub-busbar 170 is higher than that used to prepare the main busbar 130, in order to reduce the consumption of silver paste per unit.

[0066] For example, in the step-by-step printing process, the main grid 130 can be printed on the silicon wafer 110 first using the main grid printing screen, and then the secondary grid 170 can be printed on the silicon wafer 110 with the main grid 130 using the secondary grid printing screen. The secondary grid 170 can be overlapped with the main grid 130 through overprinting.

[0067] However, the overprinting of the sub-gate 170 and the main gate 130 is difficult and the overprinting accuracy is limited, which affects the reliability of the connection between the sub-gate 170 and the main gate 130. In severe cases, it can cause the sub-gate 170 to disconnect from the main gate 130, affecting the current collection of the sub-gate 170 and reducing the photoelectric conversion efficiency of the solar cell 100.

[0068] Based on this, the embodiments of this application have improved the structure of the electrode structure 120 of the solar cell 100. The electrode structure 120 of the solar cell 100 provided in the embodiments of this application will be illustrated below.

[0069] Continue to refer to Figure 1 In some examples, electrode structure 120 includes a main gate 130 and a sub-gate 170, the sub-gate 170 including a first sub-gate 140 and a second sub-gate 150, that is, electrode structure 120 includes a main gate 130, a first sub-gate 140 and a second sub-gate 150.

[0070] The main gate 130 includes a main gate line 131 and a plurality of first pads 132. The plurality of first pads 132 are spaced apart along a first direction X. The main gate line 131 extends along the first direction X and connects any two adjacent first pads 132.

[0071] The main gate 130 also includes a second pad 133, which is located on one side of a plurality of first pads 132 along a first direction X, and the main gate line 131 connects the first pads 132 and the second pads 133.

[0072] For example, the number of first pads 132 can be two, three, or more. The embodiments of this application do not further limit the number of first pads 132. The number of second pads 133 can be two. The two second pads 133 are located on both sides of the plurality of first pads 132 along the first direction X, and are respectively connected to the adjacent first pads 132 through the main gate line 131.

[0073] Understandably, the first pad 132 and the second pad 133 can connect multiple main gate lines 131 arranged along the first direction X. The solder strip is soldered to the pad (e.g., the first pad 132 and the second pad 133) and connected to the main gate line 131 through the pad, which reduces the risk of the solder strip being offset relative to the main gate line 131, resulting in poor soldering or weak soldering.

[0074] The first pad 132 and the second pad 133 may have the same shape and area, or they may be different. For example, the area of ​​the second pad 133 may be larger than the area of ​​the first pad 132 to disperse stress and reduce the risk of edge breakage of the silicon wafer 110 due to localized stress concentration. Understandably, the main gate line 131, the first pad 132, and the second pad 133 may be printed on the silicon wafer 110 in the same step.

[0075] like Figure 1 As shown, the first subgate 140 is used to overlap with the first pad 132, and the second subgate 150 is used to overlap with the second pad 133.

[0076] Figure 2 This is a schematic diagram showing the positional relationship between the first sub-gate and the first pad provided for some embodiments of this application. Figure 3 This is a schematic diagram illustrating the positional relationship between the first sub-gate and the first pad, provided for other embodiments of this application. It will be understood that in some of the accompanying drawings of this application, [the following is a simplified representation of the positional relationship between the first sub-gate and the first pad]. Figure 2 and Figure 3 For example, to clearly illustrate the structure in the attached diagram, only one pad and the sub-gate that overlaps with the pad are shown.

[0077] In some examples, such as Figure 2 As shown, the first sub-gate 140 includes a first sub-gate line 141 and a first extension 142. The first sub-gate line 141 extends along a second direction Y. The first extension 142 is located on one side of the first sub-gate line 141 along the second direction Y and is connected to the first sub-gate line 141. It can be understood that the first extension 142 and the first sub-gate line 141 can be directly connected or indirectly connected through other components. The first extension 142 is used to overlap with the first pad 132.

[0078] The first pad 132 includes a first side 1321 and a second side 1322, which extend along a second direction Y and are disposed opposite to each other along a first direction X. In the first direction X, the second side 1322 is farther away from the first subgate 140 relative to the first side 1321.

[0079] like Figure 2 As shown, the first extension 142 extends from one end away from the first sub-gate line 141 toward the direction closer to the second side 1322.

[0080] Understandably, the first extension 142 extends from one end away from the first sub-gate line 141 toward the direction closer to the second side 1322, so that the first extension 142 can provide the first sub-gate line 141 with an offset margin in the first direction X.

[0081] For example, such as Figure 2 As shown, under normal overprinting conditions, along the first direction X, the first sub-grid line 141 is located between the first side 1321 and the second side 1322, and the distance between the first sub-grid 140 and the first side 1321 is less than the distance between the first sub-grid 140 and the second side 1322.

[0082] Understandably, during the overprinting process of the first sub-gate 140 and the main gate 130, the first sub-gate 140 is prone to shifting towards the first edge 1321. When the first sub-gate 140 shifts relative to the main gate 130 along the first direction X, for example, as... Figure 3 As shown, when the first subgate line 141 is offset along the first direction X to the side of the first side 1321 away from the second side 1322, the first extension 142 extends towards the second side 1322, so that the first extension 142 can overlap with the first pad 132, that is, the first subgate 140 can overlap with the first pad 132.

[0083] This reduces the difficulty of overlaying the first sub-busbar 140 and the main busbar 130, improves the reliability of the overlap between the first sub-busbar 140 and the main busbar 130, reduces the risk of disconnection between the first sub-busbar 140 and the main busbar 130, improves the reliability of the solar cell 100, and increases the production yield of the solar cell 100.

[0084] Continue to refer to Figure 2 and Figure 3 In some examples, the end of the first extension 142 away from the first sub-gate line 141 is the first end M1.

[0085] There are multiple first sub-gates 140, including a first first sub-gate 140a and a second first sub-gate 140b. The first first sub-gate 140a and the second first sub-gate 140b are spaced apart along the second direction Y and overlap with the same first pad 132.

[0086] like Figure 2 and Figure 3 As shown, in the second direction Y, the distance between the first end M1 of the first extension 142 of the first subgate 140a and the first end M1 of the first extension 142 of the second subgate 140b is a first distance H1, which is less than the width D1 of the first pad 132 in the second direction Y.

[0087] Understandably, setting the first distance H1 to be less than the width D1 of the first pad 132 in the second direction Y can provide the first subgate 140 with an offset margin in the second direction Y.

[0088] Figure 4 This is a schematic diagram illustrating the positional relationship between a first sub-gate and a first pad, provided for some embodiments of this application. For example, as shown... Figure 4 As shown, the first distance H1 is set to be less than the width D1 of the first pad 132 in the second direction Y. During the overlay process of the first sub-gate 140 and the main gate 130, even if the first sub-gate 140 is offset relative to the first pad 132 along the second direction Y, the first sub-gate 140 can still overlap with the first pad 132. This reduces the overlay difficulty of the first sub-gate 140 and the main gate 130, improves the overlay reliability of the first sub-gate 140 and the main gate 130, reduces the risk of disconnection between the first sub-gate 140 and the main gate 130, improves the reliability of the solar cell 100, and improves the production yield of the solar cell 100.

[0089] Understandably, such as Figure 2 , Figure 3 and Figure 4 As shown, the first sub-gate 140 includes a first extension 142. The end of the first extension 142 away from the first sub-gate line 141 extends towards the second side 1322, and the first distance H1 is less than the width D1 of the first pad 132 in the second direction Y. This allows the first sub-gate 140 to have offset margin in both the first direction X and the second direction Y, reducing the overlay difficulty between the first sub-gate 140 and the main gate 130, improving the overlap reliability between the first sub-gate 140 and the main gate 130, reducing the risk of disconnection between the first sub-gate 140 and the main gate 130, improving the reliability of the solar cell 100, and improving the production yield of the solar cell 100.

[0090] Understandably, the first sub-gate 140 and the main gate 130 have an offset margin during the overlay process. As a result, there is no need to set a connecting part or other structure at the first pad 132 to connect the first sub-gate 140, which reduces the amount of silver paste used and lowers the cost of the solar cell 100.

[0091] Furthermore, when the electrode structure 120 is disposed on the light-receiving surface 1101, the shading caused by the electrode structure 120 on the light-receiving surface 1101 can be reduced, thereby improving the photoelectric conversion efficiency of the solar cell 100.

[0092] In some examples, such as Figure 2 and Figure 3 As shown, the shape of the first pad 132 can be square, or it can be hexagonal, octagonal, or other regular or irregular shapes. The embodiments of this application do not further limit the shape of the first pad 132.

[0093] In some examples, such as Figure 2 , Figure 3 and Figure 4 As shown, the first pad 132 includes a third side 1323 and a fourth side 1324, which extend along a first direction X and are arranged opposite to each other along a second direction Y.

[0094] The first subgate line 141 of the first subgate 140a intersects with the third side 1323, so that the first subgate 140a can extend into the interior of the closed pattern enclosed by the first pad 132, thereby improving the bonding reliability of the first subgate 140a and the first pad 132.

[0095] Continue to refer to Figure 2 , Figure 3 and Figure 4 The end of the first extension 142 that connects to the first sub-gate line 141 is the second end M2. In the second direction Y, the distance H5 between the second end M2 of the first extension 142 of the first sub-gate 140a and the third side 1323 ranges from 0.05 mm to 0.15 mm.

[0096] For example, in the second direction Y, the distance H5 between the second end M2 of the first extension 142 of the first sub-gate 140a and the third side 1323 can be 0.08 mm, 0.1 mm, or 0.12 mm, etc. The embodiments of this application do not further limit the value of the distance H5 between the second end M2 of the first extension 142 of the first sub-gate 140a and the third side 1323 in the second direction Y.

[0097] The distance H5 between the second end M2 of the first extension 142 of the first sub-gate 140a and the third side 1323, positioned in the second direction Y, ranges from 0.05 mm to 0.15 mm. This avoids the distance H5 from being too large (e.g., greater than 0.15 mm), thereby reducing the mutual influence between the first sub-gate 140a and the second sub-gate 140b. Furthermore, it also avoids the distance H5 from being too small (e.g., less than 0.05 mm), ensuring the reliability of the overlap between the first sub-gate 140a and the first pad 132.

[0098] Continue to refer to Figure 2 , Figure 3 and Figure 4 The first subgate line 141 of the second subgate 140b intersects with the fourth side 1324, so that the second subgate 140b can extend into the interior of the closed pattern enclosed by the first pad 132, thereby improving the bonding reliability of the second subgate 140b and the first pad 132.

[0099] In the second direction Y, the distance H6 between the second end M2 of the first extension 142 of the second first sub-gate 140b and the fourth side 1324 ranges from 0.05 mm to 0.15 mm.

[0100] For example, in the second direction Y, the distance H6 between the second end M2 of the first extension 142 of the second first sub-gate 140b and the fourth side 1324 can be 0.08 mm, 0.1 mm, or 0.12 mm, etc. The embodiments of this application do not further limit the value of the distance H6 between the second end M2 of the first extension 142 of the second first sub-gate 140b and the fourth side 1324 in the second direction Y.

[0101] The distance H6 between the second end M2 of the first extension 142 of the second first sub-gate 140b and the fourth side 1324, positioned in the second direction Y, ranges from 0.05 mm to 0.15 mm. This avoids the distance H6 from being too large (e.g., greater than 0.15 mm), thereby reducing the mutual influence between the first first sub-gate 140a and the second first sub-gate 140b. Furthermore, it also avoids the distance H6 from being too small (e.g., less than 0.05 mm), ensuring the reliable overlap between the second first sub-gate 140b and the first pad 132.

[0102] In some examples, such as Figure 2 , Figure 3 and Figure 4 As shown, the angle between the first extension 142 and the first sub-gate line 141 is an obtuse angle.

[0103] Understandably, the first extension 142 extends towards the second side 1322, and the angle between the first extension 142 and the first sub-gate line 141 is an obtuse angle. This allows the first extension 142 to provide not only offset margin in the first direction X for the first sub-gate line 141, but also offset margin in the second direction Y for the first sub-gate line 141. This reduces the overprinting difficulty between the first sub-gate 140 and the main gate 130, improves the overlap reliability between the first sub-gate 140 and the main gate 130, and reduces the risk of disconnection between the first sub-gate 140 and the main gate 130.

[0104] In some examples, the angle between the first extension 142 and the first sub-gate line 141 ranges from 120° to 150°.

[0105] For example, the angle between the first extension 142 and the first sub-gate line 141 can be 125°, 130°, or 140°, etc. The embodiments of this application do not further limit the value of the angle between the first extension 142 and the first sub-gate line 141.

[0106] Understandably, setting the angle between the first extension 142 and the first sub-gate line 141 to a range of 120° to 150° can prevent the angle between the first extension 142 and the first sub-gate line 141 from being too large (e.g., greater than 150°), so that the first extension 142 can provide sufficient offset margin for the first sub-gate line 141 in the first direction X.

[0107] Furthermore, it can also prevent the angle between the first extension 142 and the first sub-gate line 141 from being too small (e.g., less than 120°), so that the first extension 142 can provide sufficient offset margin for the first sub-gate line 141 in the second direction Y.

[0108] In some examples, the length of the first extension 142 ranges from 0.05 mm to 0.15 mm.

[0109] For example, the length of the first extension 142 can be 0.08 mm, 0.1 mm or 0.12 mm. The embodiments of this application do not further limit the length of the first extension 142.

[0110] Setting the length of the first extension 142 to a range of 0.05 mm to 0.15 mm avoids the first extension 142 from being too long (e.g., greater than 0.15 mm), thus reducing the mutual influence between the first sub-gate 140a and the second first sub-gate 140b. It also avoids the first extension 142 from being too short (e.g., less than 0.05 mm), ensuring that the first extension 142 provides sufficient offset margin for the first sub-gate line 141.

[0111] Figure 5 This is a schematic diagram showing the positional relationship between the first subgate and the first pad, provided for some embodiments of this application. Figure 6 This is a schematic diagram illustrating the positional relationship between the first sub-gate and the first pad, provided for some embodiments of this application. In some examples, such as... Figure 5 and Figure 6 As shown, the first sub-gate 140 also includes a first connecting portion 143.

[0112] For example, such as Figure 5 As shown, the first connecting portion 143 connects the first sub-gate line 141 and the first extension portion 142. Alternatively, as... Figure 6 As shown, the first sub-grid line 141 includes a first sub-segment 1411 and a second sub-segment 1412 spaced apart along the second direction Y, and a first connecting portion 143 connects the first sub-segment 1411 and the second sub-segment 1412.

[0113] Understandably, by providing the first connecting portion 143 to connect the first sub-gate line 141 and the first extension portion 142, or by providing the first connecting portion 143 to connect the first sub-segment 1411 and the second sub-segment 1412, the structural flexibility of the first sub-gate 140 can be improved.

[0114] Continue to refer to Figure 5 and Figure 6 In some examples, the width of the first connection portion 143 is greater than the width of the first sub-gate line 141 and the first extension portion 142.

[0115] This configuration improves the reliability of the first sub-gate 140. For example, when the first connecting portion 143 connects the first sub-gate line 141 and the first extension portion 142, the risk of disconnection between the first sub-gate line 141 and the first extension portion 142 can be reduced. Alternatively, when the first connecting portion 143 connects the first sub-segment 1411 and the second sub-segment 1412, the risk of disconnection between the first sub-segment 1411 and the second sub-segment 1412 can be reduced.

[0116] The embodiments of this application retain the first connecting part 143 on the basis of the original design. It is only necessary to add the pattern of the first extension part 142 (and the second sub-segment 1412) to the original sub-grid printing screen, which can reduce the appearance difference between the solar cell 100 and the original solar cell.

[0117] In some examples, the first connecting part 143 is a trapezoidal or approximately trapezoidal structure. The length of the upper base of the trapezoid ranges from 0.01 mm to 0.02 mm, the length of the lower base ranges from 0.02 mm to 0.04 mm, and the length of the legs ranges from 0.05 mm to 0.2 mm.

[0118] Understandably, the first connecting portion 143 may also be of other shapes, and the embodiments of this application do not further limit the shape of the first connecting portion.

[0119] Figure 7 This is a schematic diagram showing the positional relationship between the second sub-gate and the second pad, provided for some embodiments of this application. Figure 8 This is a schematic diagram showing the positional relationship between the second sub-gate and the second pad, provided for other embodiments of this application.

[0120] In some examples, such as Figure 7 and Figure 8 As shown, there are multiple second sub-gates 150, including a first second sub-gate 150a and a second second sub-gate 150b. The first second sub-gate 150a and the second second sub-gate 150b are spaced apart along the second direction Y and overlap with the same second pad 133.

[0121] In the second direction Y, the distance between the end of the first second sub-gate 150a near the end of the second second sub-gate 150b and the end of the second second sub-gate 150b near the end of the first second sub-gate 150a is the second distance H2, which is less than the width D2 of the second pad 133 in the second direction Y.

[0122] Understandably, setting the second distance H2 to be less than the width D2 of the second pad 133 in the second direction Y can provide the second subgate 150 with an offset margin in the second direction Y.

[0123] In other words, during the overlay process of the second sub-gate 150 and the main gate 130, even if the second sub-gate 150 is offset relative to the second pad 133 along the second direction Y, the second sub-gate 150 can still overlap with the second pad 133, reducing the overlay difficulty of the second sub-gate 150 and the main gate 130, improving the overlap reliability of the second sub-gate 150 and the main gate 130, reducing the risk of disconnection between the second sub-gate 150 and the main gate 130, improving the reliability of the solar cell 100, and improving the production yield of the solar cell 100.

[0124] Understandably, the second sub-gate 150 and the main gate 130 have an offset margin during the overlay process. As a result, there is no need to set a connection part or other structure at the second pad 133 to connect the second sub-gate 150, which reduces the amount of silver paste used and lowers the cost of the solar cell 100.

[0125] Furthermore, when the electrode structure 120 is disposed on the light-receiving surface 1101, the shading caused by the electrode structure 120 on the light-receiving surface 1101 can be reduced, thereby improving the photoelectric conversion efficiency of the solar cell 100.

[0126] In some examples, such as Figure 7 and Figure 8 As shown, the shape of the second pad 133 can be square, or it can be hexagonal, octagonal, or other regular or irregular shapes. The embodiments of this application do not further limit the shape of the second pad 133.

[0127] Continue to refer to Figure 7 and Figure 8 In some examples, electrode structure 120 also includes a harpoon portion 160. For example, the harpoon portion 160 and sub-gate 170 (including a first sub-gate 140 and a second sub-gate 150) are printed in the same step.

[0128] The harpoon portion 160 includes a harpoon line 161 and a second extension 162, the second extension 162 being connected to the harpoon line 161, and the second extension 162 and the harpoon line 161 forming an angle. The second extension 162 is used to overlap with a second pad 133. At least a portion of the harpoon line 161 is located on the side of the second pad 133 away from the first pad 132, and extends to the edge of the silicon wafer 110 (connected). Figure 1 ).

[0129] Understandably, the harpoon portion 160 is used to collect the current generated on the silicon wafer 110 on the side of the second pad 133 away from the first pad 132. The second extension 162 and the harpoon line 161 have an angle, such that the second extension 162 can provide the harpoon line 161 with an offset margin in the first direction X.

[0130] In other words, such as Figure 8 As shown, when the harpoon line 161 is offset relative to the second pad 133 along the first direction X, for example, when the harpoon line 161 is offset along the first direction X to the side of the second pad 133 away from the first pad 132, the second extension 162 can overlap with the second pad 133, reducing the difficulty of two printings, effectively ensuring the reliability of the solar cell 100 in the subsequent welding process, significantly reducing the risk of welding defects caused by misregistration, and thus improving the overall quality and production yield of the solar cell 100.

[0131] For example, the included angle between the second extension 162 and the harpoon line 161 ranges from 120° to 150°. For instance, the included angle between the second extension 162 and the harpoon line 161 can be 125°, 130°, or 140°, etc. The embodiments of this application do not further limit the value of the included angle between the second extension 162 and the harpoon line 161.

[0132] For example, the length of the second extension 162 ranges from 0.05 mm to 0.15 mm. For instance, the length of the second extension 162 can be 0.08 mm, 0.1 mm, or 0.12 mm. The embodiments of this application do not further limit the length of the second extension 162.

[0133] In some examples, such as Figure 7 and Figure 8 As shown, the harpoon portion 160 includes a first harpoon portion 160a and a second harpoon portion 160b disposed at intervals along the second direction Y.

[0134] For example, such as Figure 7 and Figure 8 As shown, along the direction from the edge of the silicon wafer 110 to the second pad 133, the distance between the harpoon line 161 of the first harpoon portion 160a and the harpoon line 161 of the second harpoon portion 160b gradually decreases. Alternatively, along the direction from the edge of the silicon wafer 110 to the second pad 133, the distance between the harpoon line 161 of the first harpoon portion 160a and the harpoon line 161 of the second harpoon portion 160b can remain constant.

[0135] Continue to refer to Figure 7 and Figure 8 In the second direction Y, the first second sub-gate 150a is located on the side of the first harpoon portion 160a away from the second harpoon portion 160b, and is connected to the second extension portion 162 of the first harpoon portion 160a.

[0136] In the second direction Y, the second sub-gate 150b is located on the side of the second harpoon portion 160b away from the first harpoon portion 160a, and is connected to the second extension portion 162 of the second harpoon portion 160b.

[0137] This configuration allows the second sub-gate 150 (the first second sub-gate 150a and the second second sub-gate 150b) to extend into the interior of the closed pattern enclosed by the second pad 133, thereby enabling the second distance H2 to be less than the width D2 of the second pad 133 in the second direction Y.

[0138] Furthermore, the first second sub-gate 150a overlaps with the second extension 162 of the first harpoon portion 160a, and the second second sub-gate 150b overlaps with the second extension 162 of the second harpoon portion 160b, so that the second extension 162 can provide the second sub-gate 150 with an offset margin along the first direction X.

[0139] In other words, when the second sub-gate 150 is offset relative to the second pad 133 along the first direction X, the second sub-gate 150 can overlap with the second pad 133 through the second extension 162, thereby improving the overlap reliability of the second sub-gate 150 and the main gate 130, reducing the risk of disconnection between the second sub-gate 150 and the main gate 130, and improving the production yield of the solar cell 100.

[0140] By adopting the above configuration, there is no need to include an extension in the second sub-gate 150, which simplifies the structure of the second sub-gate 150, saves the amount of silver paste used in the second sub-gate 150, and reduces the cost of the solar cell 100.

[0141] For example, such as Figure 7 and Figure 8 As shown, the second pad 133 includes a seventh side 1333 and an eighth side 1334, which extend along the second direction Y and are spaced apart along the first direction X.

[0142] The harpoon portion 160 intersects with one of the seventh side 1333 and the eighth side 1334. For example, as... Figure 7 and Figure 8 As shown, the harpoon portion 160 intersects with the seventh side 1333. The second sub-gate 150 is located near the edge of the seventh side 1333 and the eighth side 1334 where it intersects with the harpoon portion 160. That is, when the harpoon portion 160 intersects with the seventh side 1333, the second sub-gate 150 is closer to the seventh side 1333. At this time, along the first direction X, the distance between the second sub-gate 150 and the seventh side 1333 is less than the distance between the second sub-gate 150 and the eighth side 1334.

[0143] This reduces the distance between the harpoon portion 160 and the second sub-gate 150 in the first direction X, allowing the second sub-gate 150 to connect with the second extension portion 162.

[0144] Continue to refer to Figure 7 and Figure 8 In some examples, the second pad 133 includes a fifth side 1331 and a sixth side 1332, which extend along a first direction X and are positioned opposite each other along a second direction Y.

[0145] The first second sub-gate 150a intersects with the fifth side 1331, and in the second direction Y, the distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 ranges from 0.05 mm to 0.15 mm.

[0146] For example, in the second direction Y, the distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 can be 0.08 mm, 0.1 mm, or 0.12 mm, etc. The embodiments of this application do not further limit the value of the distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 in the second direction Y.

[0147] The distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 is set in the second direction Y. The value range is 0.05 mm to 0.15 mm. This can avoid the distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 being too large (e.g., greater than 0.15 mm), and reduce the mutual influence between the first second sub-gate 150a and the second second sub-gate 150b.

[0148] Furthermore, it can prevent the distance H7 between the end of the first second sub-gate 150a near the second second sub-gate 150b and the fifth side 1331 from being too small (e.g., less than 0.05 mm), thus ensuring the reliability of the overlap between the first second sub-gate 150a and the second pad 133.

[0149] Continue to refer to Figure 7 and Figure 8 In some examples, the second sub-gate 150b intersects with the sixth side 1332, and in the second direction Y, the distance H8 between the end of the second sub-gate 150b near the first sub-gate 150a and the sixth side 1332 ranges from 0.05 mm to 0.15 mm.

[0150] For example, in the second direction Y, the distance H8 between the end of the second sub-gate 150b near the first sub-gate 150a and the sixth side 1332 can be 0.08 mm, 0.1 mm, or 0.12 mm, etc. The embodiments of this application do not further limit the value of the distance H8 between the end of the second sub-gate 150b near the first sub-gate 150a and the sixth side 1332 in the second direction Y.

[0151] The distance H8 between the end of the second sub-gate 150b closest to the first sub-gate 150a and the sixth side 1332 is set in the second direction Y. The value range is 0.05 mm to 0.15 mm. This can avoid the distance H8 between the end of the second sub-gate 150b closest to the first sub-gate 150a and the sixth side 1332 being too large (e.g., greater than 0.15 mm), thereby reducing the mutual influence between the first sub-gate 150a and the second sub-gate 150b.

[0152] Furthermore, it can prevent the distance H8 between the end of the second sub-gate 150b near the first sub-gate 150a and the sixth side 1332 from being too small (e.g., less than 0.05 mm), thus ensuring the reliability of the overlap between the second sub-gate 150b and the second pad 133.

[0153] Figure 9 This is a schematic diagram illustrating the positional relationship between the second gate and the second pad, provided for some embodiments of this application. In some examples, such as... Figure 9 As shown, the second sub-gate 150 includes a second sub-gate line 151 and a second connecting portion 153. The second sub-gate line 151 includes a third sub-segment 1511 and a fourth sub-segment 1512 spaced apart along the second direction Y. The second connecting portion 153 connects the third sub-segment 1511 and the fourth sub-segment 1512.

[0154] The width of the second connecting portion 153 is greater than the width of the second sub-gate line 151.

[0155] This configuration improves the reliability of the second sub-gate 150 and reduces the risk of the third sub-segment 1511 and the fourth sub-segment 1512 breaking.

[0156] The embodiments of this application retain the second connecting part 153 on the basis of the original design. It is only necessary to add the pattern of the fourth sub-line segment 1512 on the original sub-grid printing screen, which can reduce the appearance difference between the solar cell 100 and the original solar cell.

[0157] In some examples, the second connecting part 153 is a trapezoidal or approximately trapezoidal structure. The length of the upper base of the trapezoid ranges from 0.01 mm to 0.02 mm, the length of the lower base ranges from 0.02 mm to 0.04 mm, and the length of the legs ranges from 0.05 mm to 0.2 mm.

[0158] Understandably, the second connecting portion 153 may also be of other shapes, and the embodiments of this application do not further limit the shape of the first connecting portion.

[0159] As can be seen from the above, in some examples, such as Figure 9As shown, the harpoon portion 160 intersects with one of the seventh side 1333 and the eighth side 1334, and the second sub-gate 150 is close to the edge of the seventh side 1333 and the eighth side 1334 that intersects with the harpoon portion 160, and is connected to the second extension portion 162.

[0160] Figure 10 This is a schematic diagram showing the positional relationship between the second sub-gate and the second pad, provided for some embodiments of this application. Figure 11 This is a schematic diagram showing the positional relationship between the second sub-gate and the second pad, provided for some embodiments of this application.

[0161] In other examples, such as Figure 10 and Figure 11 As shown, the harpoon portion 160 intersects with one of the seventh side 1333 and the eighth side 1334, and the second sub-gate 150 is positioned near the other edge of the seventh side 1333 and the eighth side 1334.

[0162] For example, such as Figure 10 and Figure 11 As shown, when the harpoon portion 160 intersects with the eighth side 1334, the second sub-gate 150 is positioned close to the seventh side 1333. That is, along the first direction X, the distance between the second sub-gate 150 and the eighth side 1334 is greater than the distance between the second sub-gate 150 and the seventh side 1333.

[0163] At this time, as Figure 10 As shown, the second sub-gate 150 may include a second sub-gate line 151 and a third extension 152. The third extension 152 is located on one side of the second sub-gate line 151 along the second direction Y and is connected to the second sub-gate line 151. Furthermore, one end of the third extension 152 away from the second sub-gate line 151 extends in a direction close to the eighth side 1334.

[0164] Understandably, the third extension 152 extends from one end away from the second sub-gate line 151 toward the direction closer to the eighth side 1334, so that the third extension 152 can provide the second sub-gate line 151 with an offset margin in the first direction X.

[0165] For example, such as Figure 10 As shown, under normal overprinting conditions, along the first direction X, the second sub-grid line 151 is located between the seventh side 1333 and the eighth side 1334, and the distance between the second sub-grid 150 and the seventh side 1333 is less than the distance between the second sub-grid 150 and the eighth side 1334.

[0166] Understandably, during the overprinting process of the second sub-grid 150 and the main grid 130, the second sub-grid 150 is prone to shifting towards the seventh side 1333. When the second sub-grid 150 shifts relative to the main grid 130 along the first direction X, for example, as... Figure 11As shown, when the second subgate line 151 is offset along the first direction X to the side of the seventh side 1333 away from the eighth side 1334, the third extension 152 extends towards the direction of the eighth side 1334, so that the third extension 152 can overlap with the second pad 133, that is, the second subgate 150 can overlap with the second pad 133.

[0167] This reduces the difficulty of overprinting the second sub-busbar 150 and the main busbar 130, improves the reliability of the overlap between the second sub-busbar 150 and the main busbar 130, reduces the risk of disconnection between the second sub-busbar 150 and the main busbar 130, improves the reliability of the solar cell 100, and increases the production yield of the solar cell 100.

[0168] In some examples, such as Figure 10 and Figure 11 As shown, the angle between the third extension 152 and the second sub-gate line 151 is an obtuse angle.

[0169] Understandably, the third extension 152 extends towards the direction close to the eighth side 1334, and the angle between the third extension 152 and the second sub-gate line 151 is an obtuse angle. This allows the third extension 152 to provide not only offset margin in the first direction X for the second sub-gate line 151, but also offset margin in the second direction Y for the second sub-gate line 151. This reduces the overprinting difficulty between the second sub-gate 150 and the main gate 130, improves the overlap reliability between the second sub-gate 150 and the main gate 130, and reduces the risk of disconnection between the second sub-gate 150 and the main gate 130.

[0170] In some examples, the angle between the third extension 152 and the second sub-gate line 151 ranges from 120° to 150°.

[0171] For example, the angle between the third extension 152 and the second sub-gate line 151 can be 125°, 130°, or 140°, etc. The embodiments of this application do not further limit the value of the angle between the third extension 152 and the second sub-gate line 151.

[0172] Understandably, setting the angle between the third extension 152 and the second sub-gate line 151 to a range of 120° to 150° can prevent the angle between the third extension 152 and the second sub-gate line 151 from being too large (e.g., greater than 150°), so that the third extension 152 can provide sufficient offset margin for the second sub-gate line 151 in the first direction X.

[0173] Furthermore, it is possible to avoid the angle between the third extension 152 and the second sub-gate line 151 being too small (e.g., less than 120°), so that the third extension 152 can provide sufficient offset margin for the second sub-gate line 151 in the second direction Y.

[0174] Understandably, when the second sub-gate 150 includes the second sub-gate line 151 and the third extension 152, the structure of the second sub-gate 150 can be similar to the structure of the first sub-gate 140. The above embodiments of this application have already illustrated the structure of the first sub-gate 140, and will not be repeated here.

[0175] Figure 12 This is a schematic diagram of the structure of a subgrid printing screen provided for some embodiments of this application. On the other hand, as... Figure 12 As shown, an embodiment of this application provides a subgrid printing screen 200.

[0176] Understandably, the sub-gate printing screen 200 is used to print sub-gates onto the silicon wafer 110 on which the main gate 130 is disposed. For example, the sub-gate printing screen 200 can be used to print the sub-gate 170 (including the first sub-gate 140 and the second sub-gate 150) in the above embodiments.

[0177] In some examples, such as Figure 12 As shown. The sub-grid printing screen 200 includes a screen body 201, on which a sub-grid printing pattern 240 is formed. The sub-grid printing pattern 240 includes a first sub-grid pattern 210 and a second sub-grid pattern 220. That is, the screen body 201 has a first sub-grid pattern 210 and a second sub-grid pattern 220.

[0178] Understandably, in the embodiments of this application, the "pattern" on the screen printing body 201 refers to the formation of through holes with a set pattern on the screen printing body 201. During the printing process, the silver paste can be printed onto the silicon wafer 110 with the main gate 130 through the pattern formed on the screen printing body 201.

[0179] Figure 13 This is a schematic diagram of the structure of a first grid pattern provided for some embodiments of this application. To clearly illustrate the structure of the drawings, some of the accompanying drawings in this application use [the following characters are used to represent the grid pattern]. Figure 13 For example, only a portion of the first grid pattern 210 is shown.

[0180] In some examples, such as Figure 13 As shown, the first sub-gate pattern 210 includes a first sub-gate line pattern 211 and a first extension pattern 212. The first sub-gate line pattern 211 extends along a second direction Y. The first extension pattern 212 is located on one side of the first sub-gate line pattern 211 along the second direction Y and is connected to the first sub-gate line pattern 211. It can be understood that the first extension pattern 212 and the first sub-gate line pattern 211 can be directly connected or indirectly connected through other structures.

[0181] like Figure 13As shown, there is an angle between the first subgrid pattern 211 and the first extension pattern 212.

[0182] Understandably, there is an angle between the first extension pattern 212 and the first sub-gate pattern 211, such that the first extension pattern 212 can provide the first sub-gate pattern 211 with an offset margin in the first direction X.

[0183] For example, when the first sub-gate pattern 211 is offset relative to the first pad 132 along the first direction X, since there is an angle between the first extension pattern 212 and the first sub-gate pattern 211, the orthographic projection of the first extension pattern 212 on the silicon wafer 110 can overlap with the orthographic projection of the first pad 132 on the silicon wafer 110, thereby enabling the first extension 142 to overlap with the first pad 132, that is, enabling the first sub-gate 140 to overlap with the first pad 132.

[0184] This reduces the difficulty of overlaying the first sub-busbar 140 and the main busbar 130, improves the reliability of the overlap between the first sub-busbar 140 and the main busbar 130, reduces the risk of disconnection between the first sub-busbar 140 and the main busbar 130, improves the reliability of the solar cell 100, and increases the production yield of the solar cell 100.

[0185] Understandably, in the embodiments of this application, taking the first extension pattern 212 as an example, the orthographic projection of the first extension pattern 212 on the silicon wafer 110 is the closed area enclosed by the orthographic projection of the edge of the first extension pattern 212 on the silicon wafer 110.

[0186] For example, the second side 1322 of the first pad 132 is away from the first subgate 140 relative to the first side 1321 of the first pad 132, and the end of the first extension pattern 212 away from the first subgate line pattern 211 can extend toward the second side 1322, so that there can be an angle between the first subgate line pattern 211 and the first extension pattern 212.

[0187] Continue to refer to Figure 13 In some examples, the angle between the first subgrid pattern 211 and the first extension pattern 212 is an obtuse angle.

[0188] Understandably, the angle between the first extension pattern 212 and the first sub-grid pattern 211 is an obtuse angle, which allows the first extension pattern 212 to provide offset margin in the first direction X for the first sub-grid pattern 211, as well as offset margin in the second direction Y for the first sub-grid pattern 211. This reduces the overprinting difficulty of the first sub-grid 140 and the main grid 130, improves the overlap reliability of the first sub-grid 140 and the main grid 130, and reduces the risk of disconnection between the first sub-grid 140 and the main grid 130.

[0189] In some examples, the angle between the first extension pattern 212 and the first sub-grid pattern 211 ranges from 120° to 150°.

[0190] For example, the angle between the first extension pattern 212 and the first sub-gate pattern 211 can be 125°, 130°, or 140°, etc. The embodiments of this application do not further limit the value of the angle between the first extension pattern 212 and the first sub-gate pattern 211.

[0191] Understandably, setting the angle between the first extension pattern 212 and the first sub-gate pattern 211 to a range of 120° to 150° can prevent the angle between the first extension pattern 212 and the first sub-gate pattern 211 from being too large (e.g., greater than 150°), so that the first extension pattern 212 can provide sufficient offset margin for the first sub-gate pattern 211 in the first direction X.

[0192] Furthermore, it can also prevent the angle between the first extension pattern 212 and the first sub-gate pattern 211 from being too small (e.g., less than 120°), so that the first extension pattern 212 can provide sufficient offset margin for the first sub-gate pattern 211 in the second direction Y.

[0193] Continue to refer to Figure 13 In some examples, the end of the first extension pattern 212 that is away from the first sub-grid pattern 211 is the third end M3.

[0194] The number of first sub-gate patterns 210 is multiple, including a first first sub-gate pattern 210a and a second first sub-gate pattern 210b, which are spaced apart along the second direction Y.

[0195] In the second direction Y, the distance between the third end M3 of the first extension pattern 212 of the first sub-gate pattern 210a and the third end M3 of the first extension pattern 212 of the second sub-gate pattern 210b is a third distance H3, which is less than the width of the first pad 132 in the second direction Y.

[0196] Understandably, setting the third distance H3 to be less than the width of the first pad 132 in the second direction Y can provide the first subgate 140 with an offset margin in the second direction Y.

[0197] In this way, even if the first sub-gate pattern 210 is offset relative to the first pad 132 along the second direction Y during the overlay process, the orthographic projection of the first sub-gate pattern 210 on the silicon wafer 110 can overlap with the orthographic projection of the first pad 132 on the silicon wafer 110, thereby enabling the first extension 142 to overlap with the first pad 132, that is, enabling the first sub-gate 140 to overlap with the first pad 132, reducing the risk of disconnection between the first sub-gate 140 and the main gate 130, improving the reliability of the solar cell 100, and increasing the production yield of the solar cell 100.

[0198] For example, the third distance H3 and the first distance H1 are equal or approximately equal.

[0199] In some examples, the length of the first extension pattern 212 ranges from 0.05 mm to 0.15 mm.

[0200] For example, the length of the first extension pattern 212 can be 0.08 mm, 0.1 mm or 0.12 mm. The embodiments of this application do not further limit the length of the first extension pattern 212.

[0201] Setting the length of the first extension pattern 212 to a range of 0.05 mm to 0.15 mm avoids the first extension pattern 212 from being too long (e.g., greater than 0.15 mm), thus reducing the mutual influence between the first sub-gate 140a and the second first sub-gate 140b. It also avoids the first extension pattern 212 from being too short (e.g., less than 0.05 mm), ensuring that the first extension pattern 212 provides sufficient offset margin for the first sub-gate line pattern 211.

[0202] Figure 14 A schematic diagram of the structure of a first grid pattern provided for other embodiments of this application. Figure 15 A schematic diagram of the structure of a first grid pattern provided for some embodiments of this application.

[0203] In some examples, such as Figure 14 and Figure 15 As shown, the first sub-gate pattern 210 includes a first connecting portion pattern 213, such as... Figure 14 As shown, the first connecting pattern 213 connects the first sub-gate line pattern 211 and the first extension pattern 212. Alternatively, as... Figure 15 As shown, the first sub-grid pattern 211 includes a first sub-segment pattern 2111 and a second sub-segment pattern 2112 spaced apart along the second direction Y, and a first connecting part pattern 213 connects the first sub-segment pattern 2111 and the second sub-segment pattern 2112.

[0204] Understandably, setting the first connecting part pattern 213 to connect the first sub-gate line pattern 211 and the first extension pattern 212, or setting the first connecting part pattern 213 to connect the first sub-segment pattern 2111 and the second sub-segment pattern 2112, can improve the structural flexibility of the first sub-gate pattern 210.

[0205] Continue to refer to Figure 14 and Figure 15 In some examples, the width of the first connecting pattern 213 is greater than the width of the first sub-gate pattern 211 and the first extension pattern 212.

[0206] This configuration improves the reliability of the first sub-gate 140. For example, when the first connecting pattern 213 connects the first sub-gate line pattern 211 and the first extension pattern 212, the risk of disconnection between the first sub-gate line 141 and the first extension 142 can be reduced. Alternatively, when the first connecting pattern 213 connects the first sub-segment pattern 2111 and the second sub-segment pattern 2112, the risk of disconnection between the first sub-segment 1411 and the second sub-segment 1412 can be reduced.

[0207] In some examples, the first connecting part pattern 213 is a trapezoidal or approximately trapezoidal structure. The length of the upper base of the trapezoid ranges from 0.01 mm to 0.02 mm, the length of the lower base ranges from 0.02 mm to 0.04 mm, and the length of the legs ranges from 0.05 mm to 0.2 mm.

[0208] It is understood that the first connecting part pattern 213 may also be other shapes, and the embodiments of this application do not further limit the shape of the first connecting part pattern 213.

[0209] Figure 16 This is a schematic diagram illustrating the structure of a second grid pattern provided in some embodiments of this application. In some examples, such as... Figure 16 As shown, there are multiple second sub-gate patterns 220, including a first second sub-gate pattern 220a and a second second sub-gate pattern 220b, which are spaced apart along the second direction Y.

[0210] In the second direction Y, the distance between the end of the first second sub-gate pattern 220a near the end of the second second sub-gate pattern 220b and the end of the second second sub-gate pattern 220b near the end of the first second sub-gate pattern 220a is a fourth distance H4, which is less than the width of the second pad 133 in the second direction Y.

[0211] Understandably, setting the fourth distance H4 to be less than the width D2 of the second pad 133 in the second direction Y can provide the second subgate 150 with an offset margin in the second direction Y.

[0212] In other words, during the overlay process, even if the second sub-gate pattern 220 is offset relative to the second pad 133 along the second direction Y, the orthographic projection of the second sub-gate pattern 220 on the silicon wafer 110 can still overlap with the orthographic projection of the second pad 133 on the silicon wafer 110, so that the second sub-gate 150 can still overlap with the second pad 133, reducing the overlay difficulty of the second sub-gate 150 and the main gate 130, improving the overlap reliability of the second sub-gate 150 and the main gate 130, reducing the risk of disconnection between the second sub-gate 150 and the main gate 130, improving the reliability of the solar cell 100, and improving the production yield of the solar cell 100.

[0213] For example, the fourth distance H4 and the second distance H2 are equal or approximately equal.

[0214] Continue to refer to Figure 16 In some examples, the webpage body 201 has a harpoon pattern 230, which includes a harpoon line pattern 231 and a second extension pattern 232, the second extension pattern 232 and the harpoon line pattern 231 being connected. The harpoon pattern 230 includes a first harpoon pattern 230a and a second harpoon pattern 230b spaced apart along a second direction Y.

[0215] In the second direction Y, the first second sub-gate pattern 220a is located on the side of the first harpoon pattern 230a away from the second harpoon pattern 230b, and is connected to the second extension pattern 232 of the first harpoon pattern 230a.

[0216] In the second direction Y, the second sub-gate pattern 220b is located on the side of the second harpoon pattern 230b away from the first harpoon pattern 230a, and is connected to the second extension pattern 232 of the second harpoon pattern 230b.

[0217] This configuration allows the orthographic projection of the second sub-gate pattern 220 on the silicon wafer 110 to overlap with the orthographic projection of the second pad 133 on the silicon wafer 110, thereby enabling the second sub-gate 150 to extend into the interior of the closed pattern enclosed by the second pad 133, thus improving the reliability of the overlap between the second sub-gate 150 and the second pad 133.

[0218] Furthermore, the first second sub-gate pattern 220a overlaps with the second extension pattern 232 of the first harpoon pattern 230a, and the second second sub-gate pattern 220b overlaps with the second extension pattern 232 of the second harpoon pattern 230b. This allows the second extension pattern 232 of the harpoon pattern 230 to provide offset margin for the second sub-gate pattern 220 along the first direction X, improving the overlap reliability of the second sub-gate 150 and the main gate 130, reducing the risk of disconnection between the second sub-gate 150 and the main gate 130, and improving the production yield of the solar cell 100.

[0219] By adopting the above configuration, there is no need to include an extension in the second grid pattern 220, which simplifies the structure of the second grid pattern 220, saves the amount of silver paste used in the second grid 150, and reduces the cost of the solar cell 100.

[0220] Figure 17 A schematic diagram of the structure of a second grid pattern provided for other embodiments of this application. In some examples, such as Figure 17 As shown, the second sub-gate pattern 220 includes a second sub-gate line pattern 221 and a second connecting part pattern 223. The second sub-gate line pattern 221 includes a third sub-line segment pattern 2211 and a fourth sub-line segment pattern 2212 that are spaced apart along the second direction Y. The second connecting part 153 connects the third sub-line segment 1511 and the fourth sub-line segment 1512.

[0221] The width of the second connecting pattern 223 is greater than the width of the second sub-grid pattern 221.

[0222] This configuration improves the reliability of the second sub-gate 150 and reduces the risk of the third sub-segment 1511 and the fourth sub-segment 1512 breaking.

[0223] In some examples, the second connecting part pattern 223 is a trapezoidal or approximately trapezoidal structure. The length of the upper base of the trapezoid ranges from 0.01 mm to 0.02 mm, the length of the lower base ranges from 0.02 mm to 0.04 mm, and the length of the legs ranges from 0.05 mm to 0.2 mm.

[0224] It is understood that the second connecting pattern 223 may also be other shapes, and the embodiments of this application do not further limit the shape of the second connecting pattern 223.

[0225] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A solar cell, characterized in that, include: Silicon wafers, including the light-receiving side and the back-lighting side; An electrode structure is disposed on the light-receiving surface or the backlight surface; The electrode structure includes: The main gate includes a main gate line and a plurality of first pads, the plurality of first pads being spaced apart along a first direction, the main gate line extending along the first direction and connecting any two adjacent first pads; The first sub-gate includes a first sub-gate line and a first extension. The first sub-gate line extends along a second direction, which is perpendicular to the first direction. The first extension is located on one side of the first sub-gate line along the second direction and is connected to the first sub-gate line. The first extension is used to overlap with the first pad. The first pad includes a first side and a second side, the first side and the second side extend along the second direction, and the first side and the second side are disposed opposite each other along the first direction; in the first direction, the second side is away from the first sub-gate relative to the first side; the end of the first extension away from the first sub-gate line extends toward the second side.

2. The solar cell according to claim 1, characterized in that, The end of the first extension that is away from the first sub-gate line is the first end; The number of first sub-gates is multiple, and the multiple first sub-gates include a first first sub-gate and a second first sub-gate. The first first sub-gate and the second first sub-gate are spaced apart along the second direction and overlap with the same first pad. In the second direction, the distance between the first end of the first extension of the first first subgate and the first end of the first extension of the second first subgate is a first distance, which is less than the width of the first pad in the second direction.

3. The solar cell according to claim 2, characterized in that, The end of the first extension that is connected to the first sub-gate line is the second end; The first pad includes a third side and a fourth side, the third side and the fourth side extending along the first direction, and the third side and the fourth side being disposed opposite each other along the second direction; The first sub-gate line of the first sub-gate intersects the third side, and in the second direction, the distance between the second end of the first extension of the first sub-gate and the third side ranges from 0.05 mm to 0.15 mm; The first sub-gate line of the second first sub-gate intersects the fourth side, and in the second direction, the distance between the second end of the first extension of the second first sub-gate and the fourth side ranges from 0.05 mm to 0.15 mm.

4. The solar cell according to claim 1, characterized in that, The angle between the first extension and the first sub-gate line is an obtuse angle.

5. The solar cell according to any one of claims 1 to 4, characterized in that, The main gate further includes a second pad, which is located on one side of a plurality of first pads along the first direction, and the main gate line connects the first pad and the second pad; The electrode structure further includes a second sub-gate, and there are multiple second sub-gates. The multiple second sub-gates include a first second sub-gate and a second second sub-gate. The first second sub-gate and the second second sub-gate are spaced apart along the second direction and overlap with the same second pad. In the second direction, the distance between the end of the first second sub-gate near the second second sub-gate and the end of the second second sub-gate near the first second sub-gate is a second distance, which is less than the width of the second pad in the second direction.

6. The solar cell according to claim 5, characterized in that, The electrode structure further includes a harpoon portion, which includes a harpoon line and a second extension portion. The second extension portion is connected to the harpoon line, and there is an angle between the second extension portion and the harpoon line. The second extension portion is used to overlap with the second pad. At least a portion of the harpoon line is located on the side of the second pad away from the first pad and extends to the edge of the silicon wafer. The harpoon portion includes a first harpoon portion and a second harpoon portion that are spaced apart along the second direction. In the second direction, the first second sub-gate is located on the side of the first harpoon portion away from the second harpoon portion, and is connected to the second extension of the first harpoon portion; In the second direction, the second secondary gate is located on the side of the second harpoon portion away from the first harpoon portion and is connected to the second extension of the second harpoon portion.

7. The solar cell according to claim 5, characterized in that, The second pad includes a fifth side and a sixth side, the fifth side and the sixth side extending along the first direction and being disposed opposite to each other along the second direction; The first second sub-gate intersects the fifth side, and in the second direction, the distance between the end of the first second sub-gate near the second second sub-gate and the fifth side ranges from 0.05 mm to 0.15 mm; The second sub-gate intersects with the sixth side, and in the second direction, the distance between the end of the second sub-gate near the first sub-gate and the sixth side ranges from 0.05 mm to 0.15 mm.

8. A secondary grid printing screen, characterized in that, Used to print a secondary gate on a silicon wafer on which a primary gate is disposed; the primary gate includes a primary gate line and a plurality of first pads, the plurality of first pads being spaced apart along a first direction, the primary gate line extending along the first direction and connecting any two adjacent first pads; The sub-grid printing screen includes a screen body, on which a first sub-grid pattern is formed; The first sub-gate pattern includes a first sub-gate line pattern and a first extension pattern, wherein the first sub-gate line pattern extends along a second direction, and the second direction is perpendicular to the first direction; The first extension pattern is located on one side of the first sub-gate pattern along the second direction and is connected to the first sub-gate pattern; The first sub-grid pattern and the first extension pattern have an included angle.

9. The secondary grid printing screen according to claim 8, characterized in that, The end of the first extension pattern that is furthest from the first sub-gate pattern is the third end; The number of first sub-gate patterns is multiple, and the multiple first sub-gate patterns include a first first sub-gate pattern and a second first sub-gate pattern, wherein the first first sub-gate pattern and the second first sub-gate pattern are spaced apart along the second direction; In the second direction, the distance between the third end of the first extension pattern of the first sub-gate pattern and the third end of the first extension pattern of the second sub-gate pattern is a third distance, which is less than the width of the first pad in the second direction.

10. The subgrid printing screen according to claim 8 or 9, characterized in that, The angle between the first sub-grid pattern and the first extension pattern is an obtuse angle.

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