Solar cell, screen printing plate and photovoltaic module

Abstract

The embodiment of the invention provides a solar cell, a screen printing plate and a photovoltaic module, and belongs to the technical field of photovoltaic cells. The solar cell piece comprises a cell piece body and an electrode grid line structure arranged on the surface of the cell piece body, the electrode grid line structure comprises a plurality of thin grid lines which are sequentially arranged in the first direction, each thin grid line comprises a plurality of thin grid line segments, and a first interval is formed between every two adjacent thin grid line segments; the longitudinal lap joint lines are in lap joint with the adjacent fine grid line segments in the first direction; the centipede foot is located at the first interval; n fine grid line segments are arranged between every two adjacent centipede pins in the first direction at intervals, and N is a positive integer larger than or equal to 0; each fine grid line segment is in lap joint with at least one of the centipede pins and the longitudinal lap joint lines. According to the embodiment of the invention, the longitudinal lapping wires are used as one bridging means, so that the use amount of conductive slurry for forming centipede feet is reduced, and the manufacturing cost of the battery piece is effectively reduced.

Description

Technical Field

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

[0002] When printing fine grids using stencils, to ensure good strength of the stencil at multiple locations and to guarantee uniformity of the printed grid lines, the perforations in the stencil are typically short. A single perforation is insufficient to print a single fine grid line in one direction. Therefore, multiple fine grid lines in one direction are printed using multiple perforations. There are discontinuous regions between adjacent fine grid lines in one direction. To ensure current conduction in these discontinuous regions, current technology typically prints an I-shaped overlapping grid line in the discontinuous region of the fine grid while printing the main grid, connecting the fine grid lines on both sides of the discontinuous region. This overlapping method requires the number of overlapping grid lines to match the number of fine grid lines; that is, when the fine grid lines are densely distributed, the overlapping grid lines also need to be denser. Printing the overlapping grid lines together with the main grid requires different stencil structures depending on the distribution of the fine grid lines, resulting in high material consumption and costs.

[0003] It should be noted that the above content is not necessarily prior art, nor is it intended to limit the scope of patent protection of this application. Summary of the Invention

[0004] This application provides a solar cell, a screen, and a photovoltaic module to solve or alleviate one or more of the technical problems mentioned above.

[0005] As a first aspect of the embodiments of this application, this application provides a solar cell, including a cell body and an electrode grid structure disposed on the surface of the cell body, the electrode grid structure including: Multiple fine grid lines are arranged sequentially along a first direction. Each fine grid line includes multiple fine grid line segments, and a first interval is formed between adjacent fine grid line segments. The longitudinal overlap line overlaps adjacent fine grid segments along the first direction; Centipede legs, centipede legs are located in the first interval, and centipede legs overlap between adjacent fine grid segments along the extension direction of the fine grid line segment, or overlap between two adjacent longitudinal overlapping lines; In this configuration, N thin grid lines are spaced between two adjacent centipede legs along the first direction, where N is a positive integer greater than or equal to 0; each thin grid line overlaps at least one of the centipede legs and the longitudinal overlap line.

[0006] In one embodiment, the longitudinal overlap line overlaps with the fine grid line segment near the first interval.

[0007] In one embodiment, adjacent fine grid lines in a fine grid line are all connected by a longitudinal overlap line near the first interval; the longitudinal overlap line is selectively connected from the current fine grid line segment to two adjacent fine grid line segments; the centipede legs overlap between adjacent fine grid line segments along the extension direction of the fine grid line segment; a fine grid line is spaced between two adjacent centipede legs along the first direction.

[0008] In one embodiment, the centipede legs overlap between adjacent fine grid segments along the extension direction of the fine grid line segments, and N fine grid line segments are spaced apart between two adjacent centipede legs along the first direction. The N fine grid line segments overlap with one or both of the two adjacent centipede legs through longitudinal overlap lines.

[0009] In one embodiment, the longitudinal overlap line overlaps multiple fine grid lines along a first direction, and two opposing longitudinal overlap lines are provided near a first interval; the centipede legs overlap between the two opposing longitudinal overlap lines, and the centipede legs are located along the extension direction of the fine grid line segments or between two adjacent fine grid line segments along the first direction.

[0010] In one embodiment, the width of the longitudinal overlapping line is smaller than the width of the centipede's leg.

[0011] In one embodiment, the number of centipede legs along the first direction is 1 / 30 to 1 times the number of fine grid strips.

[0012] In one embodiment, the electrode grid structure further includes: a main grid line extending along a first direction and disposed at a first interval; the width of the longitudinal overlap line is smaller than the width of the main grid line.

[0013] In one embodiment, the electrode grid line structure further includes: pads disposed on the main grid line at the position where the centipede legs intersect.

[0014] As a second aspect of the embodiments of this application, this application provides a web version, including a web version body, the web version body having: Multiple first perforations extending along a first direction, and multiple first perforations distributed sequentially along a second direction; each first perforation includes multiple segments of first smaller perforations distributed successively; and / or Multiple second perforations are sequentially distributed along a first direction. Each second perforation includes multiple segments of smaller second perforations distributed along a second direction at a first preset interval. Each segment of a second perforation includes a first end and a second end. At least when the distance between two adjacent segments of smaller second perforations along the first direction is greater than a first preset threshold, the first / second end is connected to at least one first perforation. The first threshold is adapted to the spacing between two adjacent fine grid lines along the first direction in the solar cell. The angle between the first direction and the second direction is 30°~90°.

[0015] In one embodiment, a third perforation extending along a third direction is further included, the angle between the third direction and the first direction being 0-30°; the third perforation is located between two adjacent first perforations and is connected to the second perforation.

[0016] In one embodiment, the length of the first small perforation is 1 / 30-1 of the length of the third perforation.

[0017] In one embodiment, the width of the first perforation is smaller than the width of the second perforation and smaller than the width of the third perforation.

[0018] As a third aspect of the present application, the present application provides a photovoltaic module, including solar cells from any of the above embodiments.

[0019] This application provides a hybrid overlap architecture that allows for a reduction in the number of densely distributed centipede legs in traditional designs while ensuring the electrical conductivity of the fine grid lines is maintained. By using longitudinal overlap lines as one of the bridging methods, in conjunction with a small number of centipede legs, the amount of conductive paste (such as silver paste) used to form the centipede legs is reduced, effectively lowering the manufacturing cost of the solar cell. Attached Figure Description

[0020] In the accompanying drawings, unless otherwise specified, the same reference numerals throughout the various drawings denote the same or similar parts or elements. These drawings are not necessarily drawn to scale. It should be understood that these drawings depict only some embodiments disclosed in this application and should not be construed as limiting the scope of this application.

[0021] Figure 1 This illustration shows a structural diagram of a solar cell body after fine grid lines have been printed, as provided in an embodiment of this application.

[0022] Figure 2 Show Figure 1 A partially enlarged structural diagram.

[0023] Figure 3 This illustration shows a structural schematic diagram of a solar cell body according to an embodiment of this application.

[0024] Figure 4 Show Figure 3 A partially enlarged structural diagram.

[0025] Figure 5 A schematic diagram of a prior art solar cell structure is shown.

[0026] Figure 6 Show Figure 5 A partially enlarged structural diagram.

[0027] Figure 7 This illustration shows a structural schematic diagram of a solar cell provided in another embodiment of this application.

[0028] Figure 8 Show Figure 7 A partially enlarged structural diagram.

[0029] Figure 9 This illustration shows a structural schematic diagram of a solar cell provided in another embodiment of this application.

[0030] Figure 10 Show Figure 9 A magnified schematic diagram of a portion of region A in the middle.

[0031] Figure 11 Show Figure 9 A magnified schematic diagram of a portion of region B.

[0032] Figure 12 Show Figure 9 A magnified schematic diagram of the structure of region C in the middle.

[0033] Figure 13 Show Figure 9 A magnified schematic diagram of the structure of region D in the middle.

[0034] Figure 14 Show Figure 9 A magnified schematic diagram of the structure of region E in the middle.

[0035] Figure 15 Show Figure 9 A magnified schematic diagram of the local structure of region F in the middle.

[0036] Figure 16 This is a schematic diagram of the structure of a screen printing plate provided in an embodiment of this application.

[0037] Figure 17 Show Figure 16 A partially enlarged structural diagram. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in these embodiments can be combined with each other. The application will now be described in detail with reference to the accompanying drawings and embodiments.

[0039] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0040] In this application, when numerical intervals (i.e., numerical ranges) are involved, unless otherwise specified, the distribution of selectable numerical values ​​within the numerical interval is considered continuous, and includes the two endpoints of the numerical interval (i.e., the minimum and maximum values), as well as every numerical value between these two endpoints. Unless otherwise specified, when a numerical interval refers only to integers within that numerical interval, it includes the two endpoint integers of the numerical range, as well as every integer between the two endpoints, which is equivalent to directly listing every integer. When multiple numerical ranges are provided to describe features or characteristics, these numerical ranges can be merged. In other words, unless otherwise specified, the numerical ranges disclosed in this application should be understood to include any and all subranges included therein. The "numerical value" in the numerical interval can be any quantitative value, such as a number, percentage, ratio, etc. The term "numerical interval" can be broadly included to include percentage intervals, ratio intervals, proportion intervals, etc.

[0041] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. It should be understood that these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein.

[0042] This application provides a solar cell, such as... Figures 1 to 15 As shown. The solar cell of this application embodiment includes a cell body 900 and an electrode grid structure disposed on the surface of the cell body 900. The electrode grid structure includes a plurality of fine grid lines 910 arranged sequentially along a first direction, a longitudinal overlapping line 230, and centipede legs 240.

[0043] like Figures 1 to 2 As shown, among the multiple fine grid lines 910 arranged sequentially along the first direction, each fine grid line 910 includes multiple fine grid line segments 210, and a first interval is formed between adjacent fine grid line segments 210.

[0044] like Figure 5 and Figure 6As shown, when the existing grid lines are used to overlap with the fine grid line segments 210, an I-shaped overlap line 260 is used to overlap each fine grid line segment 210 one by one. In this case, a corresponding screen needs to be set for each type of solar cell (different distribution of fine grid lines 910). If the type of solar cell is changed, the screen needs to be changed, resulting in high screen production cost and reduced printing efficiency.

[0045] In this embodiment, the longitudinal overlap line 230 overlaps adjacent fine grid line segments 210 along a first direction. The first direction can be... Figures 3 to 15 The vertical direction in the middle.

[0046] Centipede legs 240 are located in the first interval. Centipede legs 240 overlap with adjacent fine grid segments 210 along the extension direction of the fine grid line segment 210, or overlap with two adjacent longitudinal overlap lines 230.

[0047] Typically, since the fine grid lines 910 consist of multiple discontinuous fine grid line segments 210, each fine grid line 910 has a disconnected overlapping centipede foot 240, allowing the entire fine grid line 910 to overlap and achieve continuous electronic transmission. However, in this case, the density of the fine grid lines 910 varies, requiring the use of corresponding screen printing for the centipede feet 240. Based on this, the embodiment of this application uses a longitudinal overlapping line 230 to overlap, which works in conjunction with the centipede feet 240 to complete the continuous overlapping of the fine grid line segments 210. This eliminates the need for each fine grid line 910 to overlap with the centipede foot 240; in fact, the centipede feet 240 do not need to overlap with the fine grid line segments 210, but can overlap with the longitudinal overlapping line 230.

[0048] Along the first direction, N thin grid lines 210 are spaced between two adjacent centipede legs 240, where N is a positive integer greater than or equal to 0. Each thin grid line segment 210 overlaps at least one of the centipede legs 240 and the longitudinal overlap line 230. As mentioned above, it is not necessary to overlap each thin grid line 910 with a centipede leg 240 individually; therefore, multiple thin grid lines 910 can be spaced between two adjacent centipede legs 240 along the first direction. The thin grid lines 910 in the middle can be overlapped by the longitudinal overlap line 230.

[0049] In this embodiment, the electrode grid structure includes multiple fine grid lines 910 arranged sequentially along a first direction. When printing on a steel plate, considering the strength of the steel plate, the fine grid lines 910 are usually not printed through a single complete perforation, but rather through multiple discontinuous segments of small perforations. Therefore, each fine grid line 910 is not continuously extended, but is designed as multiple fine grid line segments 210, with a first interval formed between adjacent fine grid line segments 210.

[0050] The electrode grid line structure of this application embodiment also includes a longitudinal overlap line 230, which extends along the first direction and overlaps with adjacent fine grid line segments 210, thereby providing a carrier conduction path for the fine grid line segments 210 in the longitudinal direction.

[0051] The electrode grid structure is also provided with centipede legs 240, which are located within the first interval. Each centipede leg 240 overlaps between adjacent fine grid segments 210 along the extension direction of the fine grid segment 210, or selectively overlaps between two adjacent longitudinal overlap lines 230.

[0052] In this embodiment, two adjacent, discontinuous fine grid line segments 210 on a fine grid line 910 are connected by a longitudinal overlap line 230. This longitudinal overlap line 230 can overlap multiple fine grid lines 910 distributed along a first direction. Then, a centipede leg 240 is laterally overlapped, and the centipede leg 240 overlaps with the longitudinal overlap line 230. Thus, the centipede leg 240 can overlap with the multiple fine grid lines 910 overlapped by the longitudinal overlap line 230. Therefore, the longitudinal setting allows for a gap of N fine grid line segments 210 (N being a positive integer greater than or equal to 0) between two adjacent centipede legs 240 along the first direction. Each fine grid line segment 210 overlaps at least one of the centipede leg 240 and the longitudinal overlap line 230, ensuring that the fine grid line 910 can overlap onto, for example, a main grid line 920 or a solder strip.

[0053] This application provides a hybrid overlap architecture that allows for a reduction in the number of densely distributed centipede legs 240 in conventional designs while ensuring the electrical conductivity of the fine grid lines 910. By using longitudinal overlap lines 230 as one of the bridging methods, in conjunction with a small number of centipede legs 240, the amount of conductive paste (such as silver paste) used to form the centipede legs 240 is reduced, effectively lowering the manufacturing cost of the solar cell.

[0054] In one embodiment, the longitudinal overlap line 230 overlaps with the fine grid line segment 210 near the first interval.

[0055] Positioning the longitudinal lap joint 230 at the end of the fine grid line segment 210 (i.e., near the first interval) can effectively bridge the electrical gaps caused by segmentation. This positioning allows the longitudinal lap joint 230 and the centipede legs 240 to be spatially coordinated to form a connection network, laying the foundation for further optimization of the arrangement density and method of the centipede legs 240, thereby serving the core objective of reducing the amount of material used in the centipede legs 240.

[0056] In one embodiment, adjacent fine grid line segments 210 in a fine grid line 910 are all overlapped with longitudinal overlap lines 230 at positions near the first interval; the longitudinal overlap lines 230 are selectively overlapped between two adjacent fine grid line segments 210 by the current fine grid line segment 210; centipede legs 240 overlap between adjacent fine grid line segments 210 along the extension direction of the fine grid line segment 210; a fine grid line 910 is spaced between two adjacent centipede legs 240 along the first direction.

[0057] like Figure 10 and Figure 11 As shown, adjacent fine grid segments 210S1 and S2 are each provided with a longitudinal overlap line 230. It can be selected to overlap with the upper fine grid segment 210R1 / R2, or one can overlap with the upper fine grid segment 210R2 and the other can overlap with the lower fine grid segment 210T1. Centipede legs 240 overlap between adjacent fine grid segments 210 along the extension direction of the fine grid segment 210. A fine grid line 910 is spaced between two adjacent centipede legs 240 along the first direction.

[0058] The aforementioned overlapping method ensures that the charge carriers of the fine gate line segment 210 are transferred to the centipede foot 240, or transferred to the longitudinal overlapping line 230 and then to the centipede foot 240. This mode achieves a standardized design where "each fine gate line 910 is connected by a longitudinal overlapping line 230, and the centipede feet 240 are distributed at intervals." Compared to overlapping every fine gate line segment 210 with a centipede foot 240, this embodiment of the application overlaps every other fine gate line segment 210 with a centipede foot 240, saving the consumption of conductive paste while maintaining the conductivity reliability of the gate network.

[0059] In one embodiment, the centipede legs 240 overlap with adjacent fine grid segments 210 along the extension direction of the fine grid line segments 210. N fine grid line segments 210 are spaced apart between two adjacent centipede legs 240 along the first direction. The N fine grid line segments 210 overlap with one or both of the two adjacent centipede legs 240 through the longitudinal overlap line 230.

[0060] like Figure 13 and Figure 14As shown in the embodiment of this application, another connection mode is described. In this mode, the centipede legs 240 also overlap between adjacent thin grid segments 210 along the extension direction of the thin grid segments 210, but there can be N (N≥0) thin grid segments 210 between two adjacent centipede legs 240 along the first direction. These N thin grid segments 210 that are not directly bridged by the centipede legs 240 are electrically connected to one or both of the two adjacent centipede legs 240 through the longitudinal overlap line 230. This mode provides greater design flexibility. By adjusting the parameter N, centipede legs 240 with different densities can be used in different areas. In areas with low current density or extreme sensitivity to material cost, a larger N value (i.e., sparser centipede legs 240) can be set, mainly relying on the longitudinal overlap line 230 for series connection; while in areas where enhanced current collection capability is required, a smaller N value can be set. This architecture, with "vertical connecting line 230 as the main trunk and centipede legs 240 as selective reinforcement points," can minimize the amount of centipede legs 240 used while ensuring performance, thereby further reducing costs.

[0061] In one embodiment, the longitudinal overlap line 230 overlaps multiple segments of fine grid lines 910 along the first direction, and two opposing longitudinal overlap lines 230 are provided near the first interval; the centipede leg 240 overlaps between the two opposing longitudinal overlap lines 230, and the centipede leg 240 is located along the extension direction of the fine grid line segment 210 or between two adjacent fine grid line segments 210 along the first direction.

[0062] like Figure 12 and 15 As shown, and Figure 3 , Figure 4 , Figure 7 and Figure 8 As shown, this embodiment describes another connection mode. The longitudinal overlap line 230 extends along the first direction and overlaps multiple (more than two) fine grid lines 910 at once. Specifically, near the two sides of the first interval, there are two opposing longitudinal overlap lines 230, which overlap the fine grid line segments 210 on both sides of the first interval, respectively. The centipede legs 240 overlap between these two opposing longitudinal overlap lines 230, and their position can be located on the line connecting the two fine grid line segments 210 along their extension direction, or in the area between two adjacent fine grid line segments 210 along the first direction. This mode upgrades the longitudinal overlap line 230 into a "long-distance bus", and the function of the centipede legs 240 becomes to connect two opposing longitudinal overlap lines 230, rather than directly connecting the fine grid line segments 210. This greatly simplifies the connection network, allowing the centipede legs 240 to be arranged more regularly and in fewer quantities. A single centipede leg 240 can achieve lateral interconnection between multiple pairs of fine grid segments 210, resulting in high connection efficiency. This allows for a wider range of electrical interconnections to be completed with less centipede leg 240 material, leading to significant cost savings.

[0063] In one example, the centipede foot 240 can still be connected to the extension direction of the fine gate line 910, which allows the charge carriers on the fine gate line 910 to be transferred to the centipede foot 240.

[0064] In other examples, the centipede legs 240 are staggered from the fine grid lines 910, so the charge carriers in the fine grid lines 910 are transmitted to the longitudinal lap line 230 and then to the centipede legs 240; either method is acceptable, but preferably the centipede legs 240 can be lapped on the extension line of the fine grid lines 910, which can also avoid the grid lines being too complicated.

[0065] In this embodiment, it is not necessary to connect a centipede foot 240 to each fine grid line 910. Instead, a one-to-many approach can be used, where multiple fine grid lines 910 share one centipede foot 240. The number of centipede feet 240 should not be too many or too few. Too many would make it unnecessary to set up the vertical connection line 230, while too few would increase the carrier transmission path and affect the carrier transmission efficiency. Therefore, there is a gap of N fine grid lines 910 between adjacent centipede feet 240. When N is 0, it means that one fine grid line 910 corresponds to one centipede foot 240; when N is 1, it means that one centipede foot 240 is connected for every other fine grid line 910. Specifically, N can be up to 1 / 5 of the number of fine grid lines 910, meaning that at least 6 centipede feet 240 should be provided in the solar cell to ensure the carrier transmission speed.

[0066] In one embodiment, the width of the longitudinal overlapping line 230 is smaller than the width of the centipede leg 240.

[0067] The width of the longitudinal overlap line 230 is designed to be smaller than the width of the centipede foot 240. The longitudinal overlap line 230 is primarily responsible for the longitudinal extension connection of the "line," and its current carrying capacity is typically lower than that of the centipede foot 240, which needs to achieve "point" or "short-distance surface" connections. Therefore, designing its width to be smaller further reduces the amount of conductive paste used in this part while meeting electrical performance requirements. This, combined with measures to reduce the amount of centipede foot 240 used, lowers the overall material cost of the electrode grid structure. The narrow longitudinal overlap line 230 also provides more layout space for the centipede foot 240 and the fine grid line 910.

[0068] In one embodiment, the number of centipede legs 240 along the first direction is 1 / 30 to 1 times the number of fine grid bars.

[0069] This embodiment quantifies and limits the number of centipede legs 240. Along the first direction, the number of centipede legs 240 is 1 / 30 to 1 times the number of fine grid lines 910. A longitudinal overlap line 230 may be provided with multiple centipede legs 240.

[0070] For example, the number of centipede legs 240 is 1 times the number of fine grid strips, that is, each fine grid line 910 overlaps with one centipede leg 240, which is the case with the maximum number of centipede legs 240.

[0071] For example, if the number of centipede legs 240 is half the number of fine grid lines, it can mean that one centipede leg 240 is erected every other fine grid line 910. Alternatively, one centipede leg 240 can be erected in the middle area of ​​the battery cell for every fine grid line 910, and one centipede leg 240 can be erected in the edge area of ​​the battery cell for every multiple fine grid lines 910.

[0072] In one embodiment, the electrode grid line structure further includes: a main grid line 920, which extends along a first direction and is disposed at a first interval; the width of the longitudinal overlap line 230 is smaller than the width of the main grid line 920.

[0073] The electrode grid structure also includes a main grid line 920 extending along a first direction to obtain a main grid cell. The main grid line 920 is located in the first interval. Furthermore, the width of the longitudinal overlap line 230 is smaller than the width of the main grid line 920. The main grid line 920 is introduced to collect the current collected by the fine grid line 910, forming a current transmission path (fine grid line 910 -> centipede foot 240 / longitudinal overlap line 230 -> main grid line 920). The width of the longitudinal overlap line 230 is smaller than the width of the main grid line 920, establishing a width hierarchy of "main grid line 920 > centipede foot 240 > longitudinal overlap line 230," ensuring the rationality and reliability of the current collection path, while adhering to the principle of minimizing material usage in non-critical conductive paths. The entire grid system optimizes cost while ensuring electrical performance.

[0074] In one embodiment, the electrode grid line structure further includes a pad 250, which is disposed on the main grid line 920 at the position where it intersects with the centipede leg 240.

[0075] The pad 250 is used for welding the solder strip. The pad 250 is set on the main bus line 920 at the position where it intersects with the centipede foot 240. The pad 250 is set at this intersection position so that the pad 250 has a strong grip with the surface of the cell, which can fix it more firmly to the surface of the cell. The pad 250 at this position can also have a stronger grip with the solder strip, which can weld it more firmly to the solder strip.

[0076] This application provides a screen printing version, such as... Figures 16-17 As shown, the web version includes a web version body 100, and the web version body 100 has the following features: Multiple first perforations extending along a first direction, and multiple first perforations distributed sequentially along a second direction; each first perforation includes multiple segments of first small perforations 120 distributed successively; and / or Multiple second perforations are sequentially distributed along a first direction. Each second perforation includes multiple segments of second small perforations 130 distributed along a second direction at a first preset interval. Each segment of the second perforation includes a first end and a second end. At least when the distance between two adjacent segments of the second small perforations 130 along the first direction is greater than a first preset threshold, the first / second end is connected to at least one first perforation. The first threshold is adapted to the distance between two adjacent fine grid lines 910 along the first direction in the solar cell. The angle between the first direction and the second direction is 30°~90°.

[0077] The screen provided in this embodiment is used to print centipede legs 240 overlapping with the fine grid lines 910 on the surface of the battery cell body 900 after the fine grid lines 910 are printed on the steel plate. After the fine grid lines 910 are printed on the steel plate, in order to ensure the strength of the steel plate and the uniformity of the printing width of the fine grid lines 910, the fine grid lines 910 printed usually include multiple broken areas, that is, one fine grid line 910 is divided into multiple fine grid lines 910, and there is a first interval 201 between adjacent fine grid lines 910. Therefore, it is necessary to print overlapping lines to realize the overlapping of the fine grid lines 910 and / or the overlapping of the fine grid lines 910 with the main grid lines 920.

[0078] In traditional printing, each fine grid line 910 is connected to the interrupted portion of the fine grid line 910 using centipede legs 240. However, in the embodiment of this application, the interrupted fine grid line 910 is connected by the cooperation of the centipede legs 240 and the longitudinal overlapping line 230.

[0079] The screen printing plate provided in this embodiment includes a screen printing plate body 100, on which a specific perforation pattern is provided. A first pattern consists of multiple first perforations extending along a first direction, which are sequentially distributed along a second direction. Each first perforation includes multiple segments of first smaller perforations 120 distributed sequentially, which are used to print fine grid lines 210. A second pattern consists of multiple second perforations sequentially distributed along the first direction, each second perforation including multiple segments of second smaller perforations 130 (used to print fine grid lines 210) distributed along the second direction at a first preset interval. Each segment of second smaller perforation 130 has a first end and a second end. At least when the distance between two adjacent segments of second smaller perforations 130 along the first direction is greater than a first preset threshold (which is adapted to the distance between adjacent fine grid lines 910 in the battery cell), the first end or the second end communicates with at least one of the first perforations. The included angle between the first direction and the second direction is 30° to 90°.

[0080] The screen printing plate includes a first stencil and / or a second stencil, meaning that the grid lines corresponding to the two types of stencils can be printed using two separate screen printing plates, requiring two printing cycles. The first screen printing plate has the first stencil and prints the grid lines corresponding to it, while the second screen printing plate has the second stencil and prints the grid lines corresponding to it. However, if the screen printing plate has both a first stencil and a second stencil, the printing can be completed in a single cycle.

[0081] The screen printing plate provided in this application provides a method for longitudinally overlapping the fine grid lines 910 by printing longitudinal overlap lines 230 through the first small perforation 120. Furthermore, by providing a horizontally arranged second small perforation 130, centipede legs 240 are printed. The centipede legs 240 can overlap with either the longitudinal overlap lines 230 or the fine grid lines 910, without requiring a one-to-one overlap with each fine grid line 910. Therefore, regardless of the distribution of the fine grid lines 910 on the surface of the solar cell body 900, such as 160 lines or 108 lines, overlap can be achieved using the same screen printing plate, eliminating the need to design a separate screen printing plate for each type of fine grid structure. This significantly simplifies the screen printing plate design process, reduces manufacturing costs and process complexity, and significantly improves the compatibility and flexibility of the printing process, providing reliable technical support for the high-precision and high-efficiency production of solar cells.

[0082] In one embodiment, a third perforation 110 extending along a third direction is further included, the angle between the third direction and the first direction being 0-30°; the third perforation 110 is located between two adjacent first perforations and is connected to the second perforation.

[0083] The screen in this embodiment also includes a third perforation 110 extending along a third direction, the angle between the third direction and the first direction being 0-30° (nearly parallel).

[0084] In a preferred example, both the first direction and the third direction are perpendicular to the fine grid lines 910 on the surface of the cell body 900.

[0085] The third perforation 110 is used to print the main grid line 920, which is printed between two adjacent longitudinal overlapping lines 230 to overlap with the centipede leg 240.

[0086] In this application embodiment, the included angle between the first cutout and the third cutout 110 is limited to 0-30°, that is, it is not limited to a parallel arrangement, and a slight tilt at a certain small angle is also within the protection scope of this application embodiment.

[0087] When the broken areas of the multiple fine grid lines 910 obtained by steel plate printing are completely aligned, the angle between the two first stencils can approach 0°, and the angle between the first stencil and the third stencil 110 can approach 0°, that is, the longitudinal overlap line 230 is parallel to the main grid line 920, which can ensure that the longitudinal overlap line 230 overlaps with the fine grid line 910.

[0088] Furthermore, during the steel plate printing process, the length of the broken area in the fine grid line 910 may have some deviation or error. In order to ensure the overlap between the longitudinal overlap line 230 and the fine grid line 910, when printing the longitudinal overlap line 230, first ensure that the first cutout at the printing start point overlaps with the fine grid line 910, and then the extension direction of the first cutout gradually tilts towards the fine grid line 910, so that the subsequent printed longitudinal overlap line 230 can overlap with the fine grid line 910.

[0089] In one embodiment, along the extending direction of the third perforation 110, there are multiple pairs of first small perforations 120, and the spacing between adjacent first small perforations 120 is less than 1 mm.

[0090] In this embodiment, the width of the first perforation may be narrower than the width of the third perforation 110. To ensure the strength of the screen, the first perforation on one side of the third perforation 110 can be set to be disconnected. That is, the longitudinal overlap line 230 on one side of the main grid line 920 is composed of multiple segments, and the disconnection area between adjacent segments of the longitudinal overlap line 230 is less than 1mm. In fact, its disconnection area is smaller than the distance between two adjacent fine grid lines 910, ensuring that two adjacent segments of the longitudinal overlap line 230 overlap with the two adjacent fine grid lines 910, thereby ensuring that the longitudinal overlap line 230 overlaps with multiple fine grid lines 910.

[0091] In this embodiment, the longitudinal overlap line 230 on one side of the main grid line 920 is composed of multiple segments, and the segments of the longitudinal overlap line 230 are disconnected, so that when the longitudinal overlap line 230 is printed with a steel plate, the steel plate has strong rigidity and a long service life.

[0092] In one embodiment, the length of the first small perforation 120 is 1 / 30 to 1 / 30 of the length of the third perforation 110. For example, it can be 1 / 30, 1 / 26, 1 / 20, 1 / 18, 1 / 12, 1 / 9, 1 / 3, 1 / 2, or 1 / 3 of the length of the third perforation 110. The lengths of the multiple segments of the first small perforation 120 may not be equal.

[0093] For example, the length of the first small perforation 120 is 1 times the length of the third perforation 110, that is, the length of the first small perforation 120 on one side of the third perforation 110 is equal to that of the third perforation 110, so the first small perforation 120 is a continuous and uninterrupted setting.

[0094] For example, the length of the first small perforation 120 is half the length of the third perforation 110. The first small perforation 120 on one side of the third perforation 110 can be divided into two segments, one of which is half the length of the third perforation 110. Since there is a break between the two segments of the first small perforation 120, the length of the other segment of the first small perforation 120 can be less than half the length of the third perforation 110. The difference between the two segments can be equal to the length of the break.

[0095] The longest possible length of the first small perforation 120 is the same as the length of the third perforation 110, meaning that the continuous longitudinal overlapping lines 230 are printed without interruption. If the length of the first small perforation 120 is too short, it is difficult to achieve multiple uses for a single plate. The first small perforation 120 is interrupted in the middle, and each segment of the longitudinal overlapping line 230 printed in the first small perforation 120 must overlap with at least the fine grid line 910. If it is divided into too many segments, it is difficult to ensure that the screen is suitable for various types of battery cells. Therefore, in this embodiment, the length of the first small perforation 120 is greater than or equal to 1 / 30 of the length of the third perforation 110, that is, the number of segments of the first small perforation 120 is less than or equal to 31 segments.

[0096] In one embodiment, the width of the first perforation is smaller than the width of the second perforation and smaller than the width of the third perforation 110.

[0097] This embodiment limits the width of the first perforation to be smaller than the width of the second perforation and smaller than the width of the third perforation 110. This ensures the width relationship of the screen printing perforation pattern, resulting in the printed longitudinal overlap line 230 being narrower than the main grid line 920 and the centipede legs 240. This limits the deposition amount of conductive paste in different functional areas, which is a key process guarantee for achieving precise control of material distribution on the solar cell and realizing cost savings.

[0098] In one example, the width of the first cutout is 1 / 3 - 1 of the width of the third cutout 110; the width of the first cutout is greater than or equal to 20 μm.

[0099] In this embodiment, the width of the first perforation is set to 1 / 3 to 1, for example, 1 / 3, 1 / 2, or 1 times the width of the main grid (third perforation 110), and ≥20 μm. The main grid line 920 is slightly wider in order to transmit charge carriers faster. The longitudinal overlap line 230 on the side of the main grid line 920 overlaps with the fine grid line 910 to transmit fewer charge carriers. Therefore, its width can be less than or equal to the width of the main grid line 920, so as to reduce the amount of paste used while reducing the light-blocking area.

[0100] In one embodiment, the first small perforation 120 is provided with a second small perforation 130 at its beginning and / or end, or is connected to the second small perforation 130; the distance between the second small perforation 130 and the beginning or end of the first small perforation 120 is 0mm-0.8mm.

[0101] The first small perforation 120 may consist of multiple broken segments. The second small perforation 130 needs to overlap with each of the multiple segments of the first small perforation 120, and cannot overlap in the broken area between adjacent segments of the first small perforation 120. When the overlap position of the second small perforation 130 is 0 mm from the end of the first small perforation 120, the centipede foot 240 and the longitudinal overlap line 230 form a T-shaped structure, resulting in low overlap resistance. Since the longitudinal overlap line 230 has already overlapped with the fine grid line 910, the centipede foot 240 can overlap at any position on the longitudinal overlap line 230 to achieve overlap and conduction with the fine grid line 910. Therefore, the centipede foot 240 does not need to be placed near the edge of the longitudinal overlap line 230. When the overlap position of the second small perforation 130 is greater than 0 mm and less than 0.8 mm from the end of the first small perforation 120, a stable overlap between the centipede foot 240 and the longitudinal overlap line 230 can be ensured, avoiding incomplete connections. The fine grid line 910 overlaps with the longitudinal overlap line 230, and ultimately, the carriers are transferred to the main grid line 920 via the centipede foot 240. The width of the centipede foot 240 can be greater than or equal to the width of the longitudinal overlap line 230, and less than or equal to the width of the main grid line 920. The width of the longitudinal overlap line 230 can be greater than or equal to the width of the fine grid line 910. Correspondingly, the width of the second aperture is greater than or equal to the width of the first aperture, and less than or equal to the width of the third aperture 110; the width of the third aperture 110 is greater than or equal to the width of the first aperture.

[0102] In one embodiment, the distance between the first and third perforations 110 is greater than or equal to 1.2 mm. In the stencil printing of fine grid lines 910, the break area of ​​the fine grid lines 910 is typically 2-5 mm. The third perforation 110 is located in the middle of the break area. The distance between the third perforation 110 and the first perforation needs to be greater than or equal to half of the break area to ensure that the first perforation overlaps with the fine grid lines 910. The distance between the first and third perforations 110 can be set according to the conventional length of the break area in the fine grid lines 910, and is only required to be greater than half of the conventional length of the break area.

[0103] In one embodiment, the screen is a steel screen with a thickness of 20 µm–200 µm. The third stencil 110, the first small stencil 120, and / or the second small stencil 130 are formed by laser cutting, electroforming, or etching. Steel plate printing is becoming a new trend in printing grid lines, offering a long service life. Using steel plate printing can simplify the printing process and improve printing efficiency.

[0104] This application provides a photovoltaic module, including solar cells from any of the above embodiments.

[0105] By employing solar cells with an optimized electrode grid structure, this photovoltaic module maintains high conversion efficiency and reliability while reducing the cost of its core cells, making the overall manufacturing cost of the photovoltaic module more competitive in the market. The reduced amount of "centipede legs" 240 on the cells and the optimized connection structure also help reduce the risk of stress concentration during the module lamination process, potentially improving the long-term reliability of the module.

[0106] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0107] For ease of description, directional terms such as "front, back, up, down, left, right," "horizontal, vertical, horizontal," and "top, bottom" generally indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. These terms are used solely for the convenience of describing this application and simplifying the description. Unless otherwise stated, these directional terms do not indicate or imply that the device or element referred to must have a specific orientation or be constructed and operated in a specific orientation, and therefore should not be construed as limiting the scope of protection of this application. The directional terms "inner" and "outer" refer to the inner or outer contours relative to the components themselves. For example, if a device in the drawings is inverted, a device described as "above" or "on top of" other devices or structures will subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein are interpreted accordingly.

[0108] Unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0109] Unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0110] Unless otherwise specifically stated, the relative arrangement, numerical expressions, and values ​​of the components and steps described in these embodiments do not limit the scope of this application. It should also be understood that, for ease of description, the dimensions of the various parts shown in the drawings are not drawn to actual scale. Techniques, methods, and devices known to those skilled in the art may not be discussed in detail, but where appropriate, such techniques, methods, and devices should be considered part of the specification. In all examples shown and discussed herein, any specific values ​​should be interpreted as merely exemplary and not as limitations. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters in the following drawings denote similar items; therefore, once an item is defined in one drawing, it need not be further discussed in subsequent drawings.

[0111] It should also be noted that the terms "one embodiment," "another embodiment," or "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this application.

[0112] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0113] It should also be noted that the above are merely preferred embodiments of this application and do not limit the scope of patent protection of this application. Any equivalent structural or procedural changes made using the content of this application’s specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the scope of patent protection of this application.

Claims

1. A solar cell, characterized in that, The battery cell body includes an electrode grid structure disposed on the surface of the battery cell body, wherein the electrode grid structure includes: Multiple fine grid lines are arranged sequentially along a first direction, each of the fine grid lines comprising multiple fine grid line segments, with a first interval formed between adjacent fine grid line segments; A longitudinal overlap line, wherein the longitudinal overlap line overlaps adjacent fine grid segments along the first direction; Centipede legs, the centipede legs are located in the first interval, the centipede legs overlap between adjacent segments of the fine grid line segment along the extension direction of the fine grid line segment, or overlap between two adjacent longitudinal overlap lines; Wherein, N fine grid lines are spaced apart between two adjacent centipede legs along the first direction, where N is a positive integer greater than or equal to 0; each fine grid line overlaps at least one of the centipede leg and the longitudinal overlap line.

2. The solar cell according to claim 1, characterized in that, The longitudinal overlap line overlaps with the fine grid line segment at a position close to the first interval.

3. The solar cell according to claim 2, characterized in that, In a single fine grid line, adjacent fine grid line segments are all connected by a longitudinal overlapping line near the first interval; the longitudinal overlapping line is selectively connected from the current fine grid line segment to two adjacent fine grid line segments; the centipede legs overlap between adjacent fine grid line segments along the extension direction of the fine grid line segment; a fine grid line is spaced between two adjacent centipede legs along the first direction.

4. The solar cell according to claim 2, characterized in that, The centipede legs overlap between adjacent segments of the fine grid line along the extension direction of the fine grid line. There are N fine grid line segments between two adjacent centipede legs along the first direction. The N fine grid line segments overlap with one or both of the two adjacent centipede legs through the longitudinal overlap line.

5. The solar cell according to claim 2, characterized in that, The longitudinal overlapping line overlaps multiple segments of the fine grid line along the first direction, and two opposing longitudinal overlapping lines are provided near the first interval; the centipede leg overlaps between the two opposing longitudinal overlapping lines, and the centipede leg is located along the extension direction of the fine grid line segment or between two adjacent fine grid line segments along the first direction.

6. The solar cell according to any one of claims 1 to 5, characterized in that, The width of the longitudinal lap joint is less than the width of the centipede's leg.

7. The solar cell according to claim 6, characterized in that, Along the first direction, the number of centipede legs is 1 / 30 to 1 times the number of fine grid strips.

8. The solar cell according to claim 7, characterized in that, The electrode grid structure further includes: a main grid line, which extends along the first direction and is disposed at the first interval; the width of the longitudinal overlap line is smaller than the width of the main grid line.

9. The solar cell according to claim 8, characterized in that, The electrode grid structure further includes: a pad, which is disposed on the main grid line at the position where it intersects with the centipede's legs.

10. A screen printing plate, characterized in that, Includes a web version body, wherein the web version body has: Multiple first perforations extending along a first direction, and multiple first perforations distributed sequentially along a second direction; each first perforation includes multiple segments of first smaller perforations distributed successively; and / or Multiple second perforations are sequentially distributed along the first direction. Each second perforation includes multiple segments of second smaller perforations distributed along the second direction at a first preset interval. Each segment of the second smaller perforation includes a first end and a second end. At least when the distance between two adjacent segments of the second smaller perforations along the first direction is greater than a first preset threshold, the first / second end is connected to at least one of the first perforations. The first threshold is adapted to the spacing between two adjacent fine grid lines along the first direction in the solar cell. The angle between the first direction and the second direction is 30° to 90°.

11. The screen printing plate according to claim 10, characterized in that, It also includes a third perforation extending along a third direction, the angle between the third direction and the first direction being 0-30°; the third perforation is located between two adjacent first perforations and is connected to the second perforation.

12. The screen printing plate according to claim 11, characterized in that, The length of the first small perforation is 1 / 30-1 of the length of the third perforation.

13. The screen printing plate according to claim 11, characterized in that, The width of the first cutout is smaller than the width of the second cutout and smaller than the width of the third cutout.

14. A photovoltaic module, characterized in that, Includes the solar cell as described in any one of claims 1 to 9.

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