Electrode structure, solar cell and photovoltaic module
By employing multiple sub-grids and an electrode structure connecting the grid lines in solar cells, the problem of welded grid breakage was solved, improving the reliability and photoelectric conversion efficiency of solar cells and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-08
- Publication Date
- 2026-03-13
AI Technical Summary
In existing technologies, the narrowing of the grid line width of the main grid and the sub-grid leads to frequent grid breakage problems during welding, which affects the photoelectric conversion efficiency and reliability of solar cells.
The electrode structure employs multiple sub-grids and connecting grid lines. The connecting grid lines are used to transfer current to another sub-grid when a grid breaks during welding, eliminating the main grid design and reducing the light-shielding area of the battery body.
This improved the reliability and photoelectric conversion efficiency of solar cells and reduced production costs.
Smart Images
Figure CN223993850U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of solar cell technology, and in particular to an electrode structure, a solar cell, and a photovoltaic module. Background Technology
[0002] Solar photovoltaic technology, as a clean and renewable energy source, is closely related to global ecological environment and energy issues. Currently, since the material cost of silver paste accounts for a large proportion of the production cost of solar cells, most manufacturers reduce the width of the main and auxiliary grids to reduce the amount of silver paste used and thus effectively lower the production cost. However, due to the narrowing of the grid lines, the corresponding amount of grid paste is reduced, resulting in a corresponding decrease in grid line height. During the welding process, this insufficient grid line height easily leads to grid breakage during welding, thereby reducing the photoelectric conversion efficiency of the solar cell. Utility Model Content
[0003] This application discloses an electrode structure, a solar cell, and a photovoltaic module, which can effectively improve the reliability of solar cells.
[0004] To achieve the above objectives, in a first aspect, this application discloses an electrode structure, comprising:
[0005] A plurality of sub-gates, the plurality of sub-gates being spaced apart along a first direction and extending along a second direction, at least one of the sub-gates having a pad configured to connect solder strips; and,
[0006] A connecting gate line extends along the second direction and is connected to a plurality of said sub-gates, the connecting gate line being configured to transmit current from one of said sub-gates to another said sub-gate;
[0007] Wherein, the first direction intersects with the second direction.
[0008] In some possible implementations, the connection position of the connecting gate line and the sub-gate is offset from the position of the pad on the sub-gate.
[0009] In some possible implementations, the width of the connecting grid lines is 7µm-30µm.
[0010] In some possible implementations, among the multiple sub-gates, the width of the sub-gate with the pads is greater than the width of the sub-gate without the pads.
[0011] In some possible implementations, the width of the pad along the first direction is 0.8mm-1.2mm; and / or, the length of the pad along the second direction is 1.2mm-1.8mm.
[0012] In some possible implementations, the electrode structure further includes a first substructure and a second substructure connected to the first substructure. Both the first substructure and the second substructure include the sub-gate and the connecting gate line. The first substructure and the second substructure are symmetrically arranged with respect to an axis of symmetry along the second direction.
[0013] The first substructure and the second substructure are provided with extensions at both ends along the first direction, and the extensions are configured to connect the welding strip.
[0014] Secondly, this application also discloses a solar cell, said solar cell comprising:
[0015] The battery itself; and,
[0016] The electrode structure described in the first aspect above is disposed on the battery body.
[0017] Thirdly, this application also discloses a photovoltaic module, including a solder ribbon and a solar cell as described in the second aspect above, wherein the solder ribbon is configured to connect a plurality of the solar cells via the solder pads.
[0018] In some possible implementations, the connecting grid lines of the solar cell are located between two adjacent solder strips, and the distances between the connecting grid lines and the two adjacent solder strips are equal along the second direction.
[0019] In some possible implementations, the number N of the connecting grid lines satisfies: N = M - 1, where M is the number of solder strips.
[0020] Compared with the prior art, the beneficial effects of this application are:
[0021] This application provides an electrode structure, a solar cell, and a photovoltaic module. The electrode structure includes multiple sub-grids and connecting grid lines. The multiple sub-grids are spaced apart along a first direction and extend along a second direction. At least one sub-grid has a pad configured to connect to a solder strip. The connecting grid lines extend along the second direction and connect to the multiple sub-grids, configured to transfer current from one sub-grid to another. By eliminating the main grid lines and adding connecting grid lines for current transmission, the electrode structure of this application can, when solder strip misalignment causes sub-grid breakage, utilize the connecting grid lines to transfer current from the broken area to another sub-grid. The current is then transferred to the solder strip via the pads on the sub-grid and discharged by the solder strip, thereby effectively improving the reliability of the solar cell. Furthermore, since the connecting grid lines only transmit current and do not collect it, the width requirement is reduced compared to the main grid, resulting in a smaller shading area on the cell body. This is beneficial for improving photoelectric conversion efficiency and reducing the production cost of the solar cell. Attached Figure Description
[0022] 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.
[0023] Figure 1 This is a schematic diagram of the electrode structure disclosed in the embodiments of this application;
[0024] Figure 2 for Figure 1 A magnified view of a section at point A in the middle;
[0025] Figure 3 for Figure 2 A magnified view of a section at point B in the middle;
[0026] Figure 4 for Figure 2 A magnified view of a section at point C;
[0027] Figure 5 This is a schematic diagram of the structure of the solar cell disclosed in the embodiments of this application;
[0028] Figure 6 This is a schematic diagram of the structure of the photovoltaic module disclosed in the embodiments of this application.
[0029] Explanation of reference numerals in the attached figures:
[0030] 100 - Electrode structure; 101 - Sub-gate; 111 - Pad; 201 - Connecting gate line;
[0031] 301 - First substructure; 401 - Second substructure; 501 - Extension;
[0032] 200 - Solar cell; 210 - Cell body;
[0033] 300 - Photovoltaic modules; 310 - Solder strips;
[0034] F1 - First direction; F2 - Second direction; V - Axis of symmetry. Detailed Implementation
[0035] 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.
[0036] In this application, the terms "above" and the like 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.
[0037] 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.
[0038] Furthermore, the terms "set up," "equipped with," "connected," and "connected" 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.
[0039] 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.
[0040] Solar cells are products that convert light energy into electrical energy. Photovoltaic modules are composed of multiple solar cells connected together. In a photovoltaic module, solar cells are connected by solder ribbons. Each solder ribbon connects the front side of a solar cell to the back side of an adjacent solar cell, thus connecting the individual solar cells to form a photovoltaic module. When a solar cell is working, the current first flows to the sub-grid, then to the main grid. The main grid then transmits the current to the solder ribbons via the solder pads, forming a current loop and thus extracting the electrical energy generated by the cell itself.
[0041] Currently, silver paste is a key material in the production process of solar cells, and its cost accounts for a significant proportion of the overall production cost. In order to effectively reduce the production cost of solar cells, the industry generally focuses on reducing the amount of silver paste used. One widely adopted method is to narrow the width of the main grid and the sub-grid, thereby reducing the area of the grid lines and directly reducing the consumption of silver paste.
[0042] However, the inventors discovered that while narrowing the width of the main and auxiliary grid lines reduces the amount of grid line paste used, this results in a corresponding decrease in grid line height. Insufficiently high grid lines are highly susceptible to weld breakage during the soldering process, meaning the connection between the grid line and the solder strip is not strong enough, or even completely broken. This leads to increased current loss during transmission, consequently significantly reducing the photoelectric conversion efficiency of the solar cell.
[0043] In view of this, this application discloses an electrode structure, a solar cell, and a photovoltaic module, which can enhance the current transmission performance between the solder strip and the sub-grid by utilizing connecting grid lines, thereby effectively improving the reliability of the solar cell.
[0044] The technical solution of this application will be further described below with reference to the embodiments and accompanying drawings.
[0045] Please see Figures 1 to 2 , Figure 1 This is a schematic diagram of the electrode structure disclosed in the embodiments of this application. Figure 2 for Figure 1 A partial enlarged view of point A. In a first aspect, an electrode structure 100 is disclosed in an embodiment of this application. The electrode structure 100 includes multiple sub-gates 101 and connecting gate lines 201. The multiple sub-gates 101 are spaced apart along a first direction F1 and extend along a second direction F2. At least one sub-gate 101 has a pad 111, which is configured to connect to solder ribbons 310 (see...). Figure 6 The connecting gate line 201 extends along the second direction F2 and is connected to multiple sub-gates 101. The connecting gate line 201 is configured to transfer current from one sub-gate 101 to another sub-gate 101. The first direction F1 intersects the second direction F2.
[0046] It is understood that this application enables the sub-gate 101 to be soldered to the solder ribbon 310 by setting the solder pad 111 on the sub-gate 101. Based on this, this application eliminates the design of the main gate and instead adds a connecting grid line 201. The connecting grid line 201 can transfer the current on one sub-gate 101 to the other sub-gate 101. That is, the connecting grid line 201 plays the role of transmitting current between the two sub-gates 101. This can prevent the sub-gate 101 from breaking during soldering of the solder ribbon 310. The connecting grid line 201 can transfer the current of the broken area of one sub-gate 101 to the other sub-gate 101, and then the current of the broken area is transferred to the solder ribbon 310 through the solder pad 111 on the other sub-gate 101. Finally, the solder ribbon 310 conducts the current out, so that the solar cell 200 can have good current transmission performance, thereby effectively improving the reliability of the solar cell 200 and thus improving the reliability of the photovoltaic module 300. In addition, since the function of the connecting grid line 201 is to transmit current and not to collect current, the width requirement is reduced compared to the main grid. That is, the width of the connecting grid line 201 can be smaller than the width of the main grid, but larger or slightly larger than the width of the sub-grid 101. This allows the smaller width of the connecting grid line 201 to reduce the shading area of the cell body 210, which in turn helps to improve the photoelectric conversion efficiency of the solar cell 200 and reduce the production cost of the solar cell 200.
[0047] It is understood that the number of sub-gates 101 and connecting gate lines 201 can be set according to actual needs, and this application embodiment does not impose a specific limitation on this. In addition, the spacing between two adjacent sub-gates 101 can also be set according to actual needs, and this application embodiment does not impose a specific limitation on this.
[0048] It is understandable that the sub-grid 101 and the connecting grid line 201 can intersect perpendicularly, that is, the first direction F1 and the second direction F2 can be perpendicular. Taking the solar cell 200 as a rectangular sheet as an example, the first direction F1 can be the length direction of the solar cell 200, and the second direction F2 can be the width direction. In this case, the sub-grid 101 is arranged along the length direction of the solar cell 200, and the connecting grid line 201 is arranged along the width direction of the solar cell 200 sheet.
[0049] It is understood that the electrode structure 100 of this application can be used for electrode screen printing, or for the electrode structure 100 of a solar cell 200, and the embodiments of this application do not limit this.
[0050] Please refer to it again. Figure 2In some embodiments, the connection position between the gate line 201 and the sub-gate 101 is offset from the position of the pad 111 on the sub-gate 101. Since the pad 111 is used to connect the solder ribbon 310, the solder ribbon 310 is connected to the sub-gate 101 via the pad 111, thereby allowing the current collected by the sub-gate 101 to be discharged from the solder ribbon 310 via the pad 111. However, during the soldering process of the solder ribbon 310, it is easy to cause a break in the gate at the position corresponding to the pad 111 on the sub-gate 101. This prevents the current in the broken area from being transmitted to the solder ribbon 310, resulting in ineffective current transmission and a decrease in the photoelectric conversion efficiency of the solar cell 200. Based on this, this application, by offsetting the connection position of the connecting grid line 201 and the sub-grid 101 from the location of the pad 111 on the sub-grid 101, enables the connecting grid line 201, which is offset from the pad 111, to transfer the current in the broken grid area to another sub-grid 101 when a grid breakage occurs in the sub-grid 101. This avoids the situation where the connecting grid line 201 also breaks, thereby enabling the current in the broken grid area to be effectively transmitted. This is beneficial to improving the production yield of the solar cell 200 and the reliability of the photovoltaic module 300.
[0051] In some embodiments, the width of the connecting gate line 201 is 7um-30um. For example, the width of the connecting gate line 201 may include, but is not limited to, 7um-10um, 10um-13um, 13um-16um, 16um-19um, 19um-21um, 21um-24um, 24um-27um, and 27um-30um. Exemplarily, the width of the connecting gate line 201 may include, but is not limited to, 7um, 8um, 9um, 10um, 11um, 12um, 13um, 14um, 15um, 16um, 17um, 18um, 19um, 20um, 21um, 22um, 23um, 24um, 25um, 26um, 27um, 28um, 29um, and 30um, etc., and the embodiments of this application do not specifically limit this.
[0052] Understandably, since the connecting grid line 201 does not need to have the function of collecting current from the main grid, the width of the connecting grid line 201 can be effectively reduced compared to the existing grid line width. Under the premise of ensuring current transmission performance, this setting can effectively reduce the amount of silver paste material used and the shading area of the cell body 210, thereby effectively reducing the production cost of the solar cell 200 and improving the photoelectric conversion efficiency of the solar cell 200, and thus improving the electrical performance of the photovoltaic module 300.
[0053] When the width of the connecting grid line 201 is less than 7 μm, the connection reliability between the sub-grids 101 and the sub-grids 101 will be reduced, which may affect the current transmission performance. When the width of the connecting grid line 201 is greater than 30 μm, the shading area of the connecting grid line 201 on the cell body 210 will be increased, and the material waste of the connecting grid line 201 will be increased, which will lead to a decrease in the photoelectric conversion efficiency of the solar cell 200 and an increase in the production cost.
[0054] Please see Figures 3 to 4 , Figure 3 for Figure 2 A magnified view of a section at point B. Figure 4 for Figure 2 A partial enlarged view at point C. In some embodiments, among the multiple sub-gates 101, some sub-gates 101 may have pads 111, while other sub-gates 101 may not have pads 111. Alternatively, all sub-gates 101 may have pads 111. It is worth noting that when some sub-gates 101 have pads 111, while other sub-gates 101 do not, the width of the sub-gates 101 with pads 111 may be greater than the width of the sub-gates 101 without pads 111. Since the sub-gate 101 with pads 111 needs to be connected to the solder ribbon 310, the sub-gate 101 with pads 111 is widened to increase its current collection and transmission capabilities. This improves the transmission performance and efficiency of the sub-gate 101 transmitting current to the solder ribbon 310 via the pads 111, thereby improving the photoelectric conversion efficiency of the solar cell 200 and the reliability of the photovoltaic module 300.
[0055] Please refer to it again. Figure 3Optionally, the width of the sub-gate 101 with pads 111 is 8.8um-12.0um. For example, the width of the sub-gate 101 with pads 111 may include, but is not limited to, 8.8um-9.2um, 9.2um-9.6um, 9.6um-10.0um, 10.0um-10.4um, 10.4um-10.8um, 10.8um-11.2um, 11.2um-11.6um, and 11.6um-12.0um. For example, the width of the sub-gate 101 with pads 111 is 8.8um, 8.9um, 9.0um, 9.1um, 9.2um, 9.3um, 9.4um, 9.5um, 9.6um, 9.7um, 9.8um, 9.9um, 10.0um, 10.1um, 10.2um, 10.3um, 10.4um, 10.5um, 10.6um, 10.7um, 10.8um, 10.9um, 11.0um, 11.1um, 11.2um, 11.3um, 11.4um, 11.5um, 11.6um, 11.7um, 11.8um, 11.9um, 12.0um, etc., and this application embodiment does not specifically limit it.
[0056] Understandably, when the width of the sub-gate 101 with pads 111 is less than 8.8 μm, the current transmission and current collection capabilities of the sub-gate 101 will decrease, resulting in a decline in the electrical performance of the solar cell 200. When the width of the sub-gate 101 with pads 111 is greater than 12.0 μm, the shading area of the sub-gate 101 on the cell body 210 will increase, resulting in a decrease in the photoelectric conversion efficiency of the solar cell 200.
[0057] Understandably, considering that the electrode structure 100 of this application eliminates the main grid, and in order to further reduce the light-shielding area of the cell body 210, the centipede-like structure connecting the main grid and the sub-grid 101 is also eliminated. Since this application eliminates the centipede-like structure, the connection between the sub-grid 101 and the solder ribbon 310 in the solar cell 200 is entirely through the solder pad 111. To meet the welding pull requirements between the solder ribbon 310 and the solar cell 200, the size of the solder pad 111 needs to be appropriately increased. Based on this, this application designs the width K1 of the solder pad 111 along the first direction F1 and the length K2 of the solder pad 111 along the second direction F2, as follows:
[0058] Please refer to it again. Figure 3Optionally, the width K1 of the pad 111 along the first direction F1 is 0.8mm-1.2mm. For example, the width K1 of the pad 111 along the first direction F1 may include, but is not limited to, 0.8mm-0.9mm, 0.9mm-1.0mm, 1.0mm-1.1mm, and 1.1mm-1.2mm. Exemplarily, the width K1 of the pad 111 along the first direction F1 may include, but is not limited to, 0.80mm, 0.82mm, 0.84mm, 0.86mm, 0.88mm, 0.90mm, 0.92mm, 0.94mm, 0.96mm, 0.98mm, 1.00mm, 1.02mm, 1.04mm, 1.06mm, 1.08mm, 1.10mm, 1.12mm, 1.14mm, 1.16mm, 1.18mm, and 1.20mm, etc., and this application embodiment does not specifically limit it in this way.
[0059] When the width K1 of the pad 111 along the first direction F1 is less than 0.8 mm, the connection reliability between the pad 111 and the solder ribbon 310 will be reduced, resulting in a decrease in the current transmission efficiency of the solar cell 200. When the width K1 of the pad 111 along the first direction F1 is greater than 1.2 mm, the shading area of the pad 111 on the cell body 210 will be increased, and the material waste of the pad 111 will be increased, resulting in a decrease in the photoelectric conversion efficiency of the solar cell 200 and an increase in production cost.
[0060] Optionally, the length K2 of the pad 111 along the second direction F2 is 1.2mm-1.8mm. For example, the length K2 of the pad 111 along the second direction F2 may include, but is not limited to, 1.2mm-1.3mm, 1.3mm-1.4mm, 1.4mm-1.5mm, 1.5mm-1.6mm, 1.6mm-1.7mm, and 1.7mm-1.8mm. For example, the length K2 of the pad 111 along the second direction F2 may include, but is not limited to, 1.20mm, 1.22mm, 1.24mm, 1.26mm, 1.28mm, 1.30mm, 1.32mm, 1.34mm, 1.36mm, 1.38mm, 1.40mm, 1.42mm, 1.44mm, 1.46mm, 1.48mm, 1.50mm, 1.52mm, 1.54mm, 1.56mm, 1.58mm, 1.60mm, 1.62mm, 1.64mm, 1.66mm, 1.68mm, 1.70mm, 1.72mm, 1.74mm, 1.76mm, 1.78mm, 1.80mm, etc., and this application embodiment does not specifically limit it.
[0061] When the length K2 of the pad 111 along the second direction F2 is less than 1.2mm, the connection reliability between the pad 111 and the solder ribbon 310 will be reduced, resulting in a decrease in the current transmission efficiency of the solar cell 200. When the width K2 of the pad 111 along the second direction F2 is greater than 1.8mm, the shading area of the pad 111 on the cell body 210 will increase, and the material waste of the pad 111 will also increase, resulting in a decrease in the photoelectric conversion efficiency of the solar cell 200 and an increase in production costs.
[0062] Therefore, the design of the width and length of the pad 111 in this application can achieve a good match between the width and length of the pad 111 and the width of the corresponding sub-gate 101, so that the sub-gate 101 and the solder ribbon 310 can achieve good current transmission performance and current transmission efficiency through the pad 111, thereby improving the photoelectric conversion efficiency of the solar cell 200 and the reliability of the photovoltaic module 300.
[0063] Please refer to it again. Figure 1 In some embodiments, the electrode structure 100 further includes a first substructure 301 and a second substructure 401 connected to the first substructure 301. The first substructure 301 and the second substructure 401 each include a sub-gate 101 and a connecting gate line 201. The first substructure 301 and the second substructure 401 are symmetrically arranged with respect to a symmetry axis V along a second direction F2.
[0064] It is understandable that the first substructure 301 and the second substructure 401 mentioned above can be respectively set to half a solar cell. That is to say, the structure of the electrode structure 100 is symmetrically designed, so it can achieve compatibility between the whole solar cell 200 and the half solar cell 200, thereby improving the flexibility of the solar cell 200 for different assembly requirements of the photovoltaic module 300.
[0065] Please refer to it again. Figure 4 Optionally, extension portions 501 are provided at both ends of the first substructure 301 and the second substructure 401 along the first direction F1. The extension portions 501 are configured to connect the welding strip 310, that is, the extension portions 501 are welding areas for welding the welding strip 310. By providing extension portions 501 at both ends of the first substructure 301 and the second substructure 401 along the first direction F1, when the welding strip 310 is welded at both ends of the first substructure 301 and the second substructure 401, the problem of microcracks and fragmentation of the solar cell 200 due to welding can be avoided, thereby improving the photoelectric conversion efficiency of the solar cell 200 and thus improving the reliability of the photovoltaic module 300.
[0066] Optionally, the extension 501 is designed in the shape of a harpoon. The extension 501 is disposed at the edge and middle position corresponding to the electrode structure 100 and the solder strip 310, and is used to weld the solder strip 310, thereby forming an effective buffer zone for welding. This allows the solar cell 200 to be welded away from the edge, avoiding the problem of edge stress concentration causing the solar cell 200 to break.
[0067] Please see Figure 5 , Figure 5 This is a schematic diagram of the structure of a solar cell disclosed in an embodiment of this application. In a second aspect, this application also discloses a solar cell 200, which includes a cell body 210 and an electrode structure 100 as described in the first aspect above. The electrode structure 100 is disposed on the cell body 210. The solar cell 200 having the electrode structure 100 described in the first aspect can also achieve the following when a problem occurs during the welding of the solder strip 310: the current in the broken area of one sub-grid 101 can be transferred to another sub-grid 101 using the connecting grid line 201, and then the current is transferred to the solder strip 310 via the solder pad 111 on the sub-grid 101. Finally, the current is discharged by the solder strip 310, enabling the solar cell 200 to have good current transmission performance, thereby effectively improving the reliability of the solar cell 200. In addition, since the function of the connecting grid line 201 is only to transmit current and not to collect current, the width requirement is reduced compared to the main grid, which reduces the shading area of the cell body 210. This is beneficial to improving the photoelectric conversion efficiency of the solar cell 200 and reducing the production cost of the solar cell 200.
[0068] It is understood that the electrode structure 100 of this application can be disposed on the light-receiving surface of the battery body 210 or on the backlight surface of the battery body 210, and can be disposed according to actual needs. This application does not make any specific limitation on this.
[0069] Please see Figure 6Thirdly, this application also discloses a photovoltaic module 300, which includes a solder ribbon 310 and a solar cell 200 as described in the second aspect above. The solder ribbon 310 is configured to connect multiple solar cells 200 via solder pads 111. The photovoltaic module 300 with the solar cell 200 described in the second aspect can also achieve the following when a problem occurs during soldering of the solder ribbon 310: the current in the broken area of one sub-busbar 101 can be transferred to another sub-busbar 101 using the connecting grid line 201, and then the current is transferred to the solder ribbon 310 via the solder pads 111 on the sub-busbar 101. Finally, the current is discharged by the solder ribbon 310, enabling the solar cell 200 to have good current transmission performance, thereby effectively improving the reliability of the solar cell 200. In addition, since the function of the connecting grid line 201 is only to transmit current and not to collect current, the width requirement is reduced compared to the main grid, which reduces the shading area of the cell body 210. This is beneficial to improving the photoelectric conversion efficiency of the solar cell 200 and reducing the production cost of the solar cell 200.
[0070] Optionally, multiple solder strips 310 are spaced apart along the second direction F2 and extend along the first direction F1. The connecting grid line 201 is arranged parallel to the solder strips 310, so that the positions of the connecting grid line 201 and the solder strip 310 do not overlap. In this way, when soldering the solder strip 310, the connecting grid line 201 will not be broken by welding, ensuring that the function of the connecting grid line 201 in transmitting the current of one sub-grid 101 to another sub-grid 101 can be fully preserved. This effectively improves the connection reliability between the sub-grid 101 and the solder strip 310 in the solar cell 200, and thus improves the reliability of the photovoltaic module 300.
[0071] In some embodiments, the connecting grid lines 201 of the solar cell 200 are located between two adjacent solder ribbons 310. On the one hand, when a solder ribbon 310 breaks a sub-grid 101 to form a broken grid region, the current in the broken grid region can be transmitted to another sub-grid 101 via the connecting grid lines 201 located on both sides of the solder ribbon 310. This sub-grid 101 can be an adjacent sub-grid 101 or a sub-grid 101 at other locations. On the other hand, when the location of the pad 111 on the same sub-grid 101 is simultaneously broken by two adjacent solder ribbons 310, thereby causing the sub-grid 101 region between two adjacent solder ribbons 310 to lose its ability to transmit the collected current to the outside, the connecting grid lines 201 located between two adjacent solder ribbons 310 can still transmit the current in the sub-grid 101 region to other sub-grids 101, thereby effectively improving the photoelectric conversion efficiency of the solar cell 200 and the reliability of the photovoltaic module 300.
[0072] Furthermore, along the second direction F2, the distances between the connecting grid line 201 and the two adjacent solder strips 310 are equal, meaning the connecting grid line 201 is located in the middle of the two adjacent solder strips 310. This makes the overall current transmission path more even and efficient, and the path length for transmitting current from one broken grid area to another sub-grid 101 is utilized more effectively. In addition, the fact that the connecting grid line 201 is located in the middle of the two adjacent solder strips 310 makes the solar cell 200 have a simpler and more aesthetically pleasing appearance.
[0073] Optionally, the number N of connecting grid lines 201 satisfies: N = M - 1, where M is the number of solder ribbons 310. Since the connecting grid lines 201 are arranged between two adjacent solder ribbons 310, the number of connecting grid lines 201 can be one less than the number of solder ribbons 310, thereby further reducing the shading area of the cell body 210 and the amount of silver paste used, thus effectively improving the photoelectric conversion efficiency of the solar cell 200 and reducing the production cost of the photovoltaic module 300.
[0074] The following is a brief explanation of the current transfer process of the connecting grid line 201 in the solar cell 200:
[0075] First, the solder ribbon 310 extends along the first direction F1 and connects to the extension portion 501 at both ends of the first substructure 301. The connecting grid line 201 is disposed between two adjacent solder ribbons 310. During the soldering process, the solder ribbon 310 may experience a certain positional shift, causing the solder ribbon 310 to break the sub-grid 101, resulting in an open circuit in the sub-grid 101. Consequently, some current on the sub-grid 101 cannot be transmitted to the solder ribbon 310 via the solder pad 111, thus preventing some current from flowing out and reducing the photoelectric conversion efficiency of the solar cell 200. This application, without altering the existing electrode structure 100 for material preparation, eliminates the main grid design and adds a connecting grid line 201 between two adjacent solder strips 310. The connecting grid line 201 transfers current from one sub-grid 101 to the other sub-grid 101, and the connecting grid line 201 is not connected to the solder strip 310, thus avoiding the problem of the connecting grid line 201 being broken during soldering of the solder strip 310. Combined with... Figure 2When a sub-grid 101 at a location of a solder strip 310 is broken, the current at that location needs to be transferred to an adjacent solder strip 310 before being discharged. If the sub-grid 101 of an adjacent solder strip 310 is also broken, the sub-grid 101 located between these two adjacent solder strips 310 cannot discharge the current in the broken grid area. By adding a connecting grid line 201 between two adjacent solder strips 310, and connecting the connecting grid line 201 to the sub-grid 101, if the connection points of two adjacent solder strips 310 and the sub-grid 101 are broken together, the current in the broken grid area can be transferred to other sub-grids 101 via the connecting grid line 201 because it is located between the two adjacent solder strips 310. This improves the connection reliability between the sub-grid 101 and the solder strips 310, thereby improving the photoelectric conversion efficiency and production yield of the solar cell 200, and achieving reliable use of the photovoltaic module 300.
[0076] 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. An electrode structure, characterized by, The electrode structure comprises: a plurality of sub-gates, the plurality of sub-gates are arranged at intervals along a first direction, and the sub-gates extend along a second direction, at least one of the sub-gates is provided with a pad, and the pad is configured to be connected to a solder ribbon; and a connection gate line, the connection gate line extends along the second direction, and the connection gate line is connected to the plurality of sub-gates, and the connection gate line is configured to transmit current of one of the sub-gates to another of the sub-gates. The first direction intersects the second direction.
2. The electrode structure of claim 1, wherein The connection position of the connection gate line and the sub-gate is staggered with the position of the pad on the sub-gate.
3. The electrode structure of claim 1, wherein The width of the connection gate line is 7-30 um.
4. The electrode structure of claim 1, wherein Among the plurality of sub-gates, the width of the sub-gate provided with the pad is greater than the width of the sub-gate not provided with the pad.
5. The electrode structure of claim 4, wherein The width of the pad along the first direction is 0.8-1.2 mm; and / or, the length of the pad along the second direction is 1.2-1.8 mm.
6. The electrode structure according to any one of claims 1 to 5, characterized in that The electrode structure further comprises a first sub-structure and a second sub-structure connected to the first sub-structure, the first sub-structure and the second sub-structure each comprise the sub-gates and the connection gate line, and the first sub-structure and the second sub-structure are symmetrically arranged relative to a symmetry axis along the second direction. The first sub-structure and the second sub-structure are provided with an extension at the two end edges along the first direction, and the extension is configured to connect the solder ribbon.
7. A solar cell, characterized by The solar cell comprises: a cell body; and The electrode structure according to any one of claims 1-6 is arranged on the cell body.
8. A photovoltaic module, characterized by, The solar cell according to claim 7, wherein the electrode structure comprises:
9. The photovoltaic module of claim 8, wherein, The connection gate line of the solar cell is located between two adjacent solder ribbons, and along the second direction, the distance between the connection gate line and the two adjacent solder ribbons is equal.
10. The photovoltaic module of claim 9, wherein, The number N of the connection gate lines satisfies: N=M-1, wherein M is the number of the solder ribbons.