Electrode structure, back-contact solar cell, battery module and photovoltaic power generation system

Abstract

The present application relates to the technical field of solar cells and provides an electrode structure, a back-contact solar cell, a battery module, and a solar power generation system, in which a plurality of first sub-gates of the electrode structure include a first collection gate line and a first merging gate line, the first main gate includes a first edge main gate disposed near a first edge of the back-contact solar cell, and the first merging gate line has one end connected to the first edge main gate and the other end passing through a first interrupted region of a second main gate adjacent to the first edge main gate to connect to the first main gate adjacent to the first edge main gate. In this way, current in the edge region collected by the first edge main gate can be directly merged with the first main gate adjacent to the first edge main gate via the first merging gate line, eliminating the need for welding on the first edge main gate to achieve the edge region merger and avoiding stress concentration problems during the welding process, improving module yield and reliability, and fully ensuring high photoelectric conversion efficiency.

Description

[Technical Field]

[0001] Priority information This application claims priority to and the benefit of patent application bearing application number 202211588511.0, filed with the State Intellectual Property Office of China on December 12, 2022, the entire contents of which are incorporated herein by reference.

[0002] Technical Field The present application relates to the technical field of solar cells, and in particular to electrode structures, back-contact solar cells, battery modules and photovoltaic power generation systems. [Background technology]

[0003] A back-contact solar cell is a cell in which the emitter electrode and base contact electrode are all located on the back surface (non-light-receiving surface) of the cell, and since the light-receiving surface of the cell is not shielded by a metal electrode, it effectively increases the short-circuit current of the battery cell. As shown in Figure 1, in related art, to achieve confluence of thin gates of the same polarity, an insulating layer is usually formed by printing an insulating adhesive 3 on thin gates of opposite polarity, exposing the thin gates of the same polarity, and then a welding portion 1 and a bus bar 2 are printed to bring the thin gates of the same polarity into contact with each other, thereby achieving confluence of thin gates of different polarities. However, in such a case, the insulating adhesive 3 cannot withstand high temperatures, and because the welds 1 and busbars 2 are formed by printing in a later process, only low-temperature paste can be used for the welds 1 and busbars 2, which not only increases costs but also raises reliability issues. Furthermore, the insulating adhesive 3 needs to be approximately 30 μm thick to ensure good insulation, and the welds 1 and busbars 2 need to be thicker than 30 μm to avoid breakage. This requires the use of a large amount of paste, further increasing costs and causing problems such as poor adhesion between the insulating adhesive 3 and some pastes.

[0004] To solve the problem shown in Figure 1, the electrode pattern of a back-contact solar cell can be designed as shown in Figures 2 and 3. In Figure 2, the thin gate 4 is cut at the location of the dissimilar material weld 5 and busbar 6, and the edge weld 5 and busbar 6 are located at the very edge of the silicon wafer. However, if the weld 5 and busbar 6 are located at the edge of the silicon wafer, the ribbon must also cover the edge of the silicon wafer during the module manufacturing process. Because a large number of microcracks exist at the edge of the silicon wafer, stress concentration is likely to occur during the ribbon welding process, causing cracks, which not only reduces module yield but also reduces module reliability.

[0005] In FIG. 3, the thin gate 7 is cut at the dissimilar material weld 8 and bus bar 9. The outer weld 8 and bus bar 9 are positioned a certain distance from the edge of the silicon wafer, and the outer periphery of the outer weld 8 and bus bar 9 are set to the same polarity. While the design in FIG. 3 solves the problem of the design in FIG. 2, photogenerated electron-hole pairs must diffuse to the opposite polarity region in order to be effectively collected. Specifically, in the structure in FIG. 3, photogenerated electron-hole pairs in the outer edge region must diffuse long distances, on the order of millimeters or even centimeters, to reach the opposite polarity region. Recombination losses during this long-distance diffusion process result in a decrease in short-circuit current, an increase in series resistance, and a loss of fill factor, resulting in significant degradation of photovoltaic conversion performance.

[0006] Therefore, designing the electrode structure of a back-contact solar cell to solve the above problems has been one of the priorities for those skilled in the art. Summary of the Invention [Problem to be solved by the invention]

[0007] The present application provides an electrode structure, a back-contact solar cell, a battery module and a solar power generation system to solve the technical problems of low reliability and low photoelectric conversion performance of conventional back-contact solar cells. [Means for solving the problem]

[0008] The present invention is realized as follows, and an electrode structure according to an embodiment of the present invention is used in a back-contact solar cell, the back-contact solar cell including first polarity regions and second polarity regions arranged alternately; the electrode structure includes a plurality of first sub-gates and a plurality of second sub-gates spaced apart from one another, the first sub-gates collecting current in the first polarity region and the second sub-gates collecting current in the second polarity region; the electrode structure further includes a plurality of first main gates and a plurality of second main gates alternately arranged at intervals, an arrangement direction of the first main gates and the second main gates is different from an arrangement direction of the first sub-gates and the second sub-gates, the first main gates are connected to the first sub-gates, and the second main gates are connected to the second sub-gates; the plurality of first sub-gates include a first collection gate line and a first merging gate line, the first collection gate line being disconnected at the position of the second main gate, the plurality of first main gates include a first edge main gate disposed near a first edge of the back-contact solar cell, a first interruption region is formed in the second main gate adjacent to the first edge main gate, and the first merging gate line has one end connected to the first edge main gate and the other end passing through the first interruption region and connected to the first main gate adjacent to the first edge main gate; The first edge main gate has no welds and / or is not used for welding; The first edge main gate is located at the first edge.

[0009] The present application further provides a back contact solar cell, which includes the electrode structure according to any one of the above claims, and the electrode structure is disposed on a back side of the back contact solar cell.

[0010] The present application further provides a battery module including the back contact solar cell.

[0011] The present application further provides a solar power generation system including the above battery module. [Effects of the Invention]

[0012] In the electrode structure, back-contact solar cell, battery module, and solar power generation system according to the embodiments of the present application, a first collection gate line of a first sub-gate is disconnected at the position of a second main gate, a first edge main gate of the first main gate is connected to a first collection gate line in the first sub-gate so as to collect current in a first polarity region near the first edge by the first collection gate line, a first merging gate line passes through a first interrupted region in the second main gate adjacent to the first edge main gate and is connected to the first edge main gate and the first main gate adjacent to the first edge main gate, and the current collected by the first edge main gate is transmitted to the first main gate adjacent to the first edge main gate by the first merging gate line to achieve merging, thereby completing the current collection. In this way, the first edge main gate is located near the first edge of the back-contact solar cell, and the current collected by the first edge main gate can directly merge with the first main gate adjacent to the first edge main gate via the first merge gate line, eliminating the need for welding on the first edge main gate to achieve edge merging. This avoids stress concentration during the welding process, improves module yield and reliability, and allows photo-generated electron-hole pairs located near the first edge to reach the opposite polarity region without long-distance diffusion, achieving current collection and fully guaranteeing high photoelectric conversion efficiency.

[0013] Additional aspects and advantages of the present application will be set forth in part in the description that follows, and in part will be obvious from the description, or may be learned by practice of the present application. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a schematic diagram of a first type of electrode pattern design in the prior art. [Figure 2] FIG. 1 is a schematic diagram of a second type of electrode pattern design in the prior art. [Figure 3] FIG. 1 is a schematic diagram of a third type of electrode pattern design in the prior art. [Figure 4] 1 is a schematic diagram of a module of a solar power generation system according to an embodiment of the present application. [Figure 5] 1 is a schematic diagram of a battery module according to an embodiment of the present application; [Figure 6] 1 is a schematic diagram of an electrode structure according to an embodiment of the present application; [Figure 7] FIG. 2 is another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 8] FIG. 10 is a schematic diagram illustrating yet another electrode structure according to an embodiment of the present invention. [Figure 9] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 10] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 11] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 12] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 13] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. [Figure 14] FIG. 10 is yet another schematic diagram of an electrode structure according to an embodiment of the present application. DETAILED DESCRIPTION OF THE INVENTION

[0015] To clarify the objectives, technical means, and advantages of the present application, the present application will be described in more detail below with reference to the drawings and examples. Examples of the embodiments are illustrated in the drawings, and the same or similar reference numerals throughout the drawings indicate the same or similar elements, or elements having the same or similar functions. The embodiments described below with reference to the drawings are illustrative and are intended to explain the present application only, and should not be understood as limiting the present application. It should also be understood that the specific examples described herein are intended to explain the present application only, and do not limit the present application.

[0016] In the description of this application, orientations or positional relationships indicated by terms such as "upper," "lower," "left," "right," "horizontal," and "vertical" are orientations or positional relationships shown in the drawings, and are used only to facilitate or simplify the description of this application, and should not be understood to represent or imply that the devices or components shown necessarily have a specific orientation or a specific oriented structure and operation, and therefore should not be construed as limiting this application.

[0017] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply a relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature qualified as "first" or "second" may explicitly or implicitly include one or more of said features. In the description of this application, unless otherwise expressly and specifically limited, "plurality" means two or more.

[0018] In this application, unless otherwise clearly specified or limited, a first feature being "above" or "below" a second feature may include direct contact between the first and second features, or contact between the first and second features via another feature between them without direct contact. Furthermore, a first feature being "above," "above," or "on the upper surface" of a second feature may include the first feature being directly above or diagonally above the second feature, or may simply mean that the horizontal height of the first feature is higher than that of the second feature. A first feature being "below," "below," or "on the lower surface" of a second feature may include the first feature being directly below or diagonally below the second feature, or may simply mean that the horizontal height of the first feature is lower than that of the second feature.

[0019] The following disclosure provides many different embodiments or examples that can be used to realize different configurations of the present application. To simplify the disclosure of the present application, specific example components and configurations are described below. Of course, these are merely examples and are not intended to limit the present application. Furthermore, the present application may repeat reference numerals and / or alphabets in different examples; this repetition is for purposes of brevity and clarity and does not in itself indicate a relationship between the various embodiments and / or configurations discussed. Additionally, while the present application provides examples of various specific processes and materials, those skilled in the art may recognize the application of other processes and / or the use of other materials.

[0020] In this application, the first edge main gate is located near the first edge of the back-contact solar cell, and the current collected by the first edge main gate in the edge region can be directly merged with the first main gate adjacent to the first edge main gate via the first merge gate line, eliminating the need for welding on the first edge main gate to achieve the edge region merger. This avoids the problem of stress concentration during the welding process, improves module yield and reliability, and simultaneously allows photo-generated electron-hole pairs located in the region near the first edge to reach the opposite polarity region without long-distance diffusion, realizing current collection and fully guaranteeing high photoelectric conversion efficiency.

[0021] Example 1 As shown in Figures 4 and 5, the solar power generation system 1000 in the embodiment of the present application may include a battery module 200 in the embodiment of the present application, and the battery module 200 in the embodiment of the present application may include a plurality of back-contact solar cells 100 in the embodiment of the present application.

[0022] As shown in FIG. 6, the back contact solar cell 100 of the present embodiment may include a substrate 20 and an electrode structure 10 of the present embodiment, where the substrate 20 may be a silicon wafer, and the back surface of the substrate 20 may have alternating first polarity regions and second polarity regions, with the polarities of the first polarity regions and the second polarity regions being opposite. For example, the first polarity regions may be P-type doped regions and the second polarity regions may be N-type doped regions, or the first polarity regions may be N-type doped regions and the second polarity regions may be P-type doped regions, but are not limited thereto.

[0023] As shown in FIG. 6, the electrode structure 10 in the embodiment of the present application may be installed on the back side of the back-contact solar cell 100, and the electrode structure 10 may include a plurality of first sub-gates 11 and a plurality of second sub-gates 12 arranged alternately at intervals, and a plurality of first main gates 13 and a plurality of second main gates 14 arranged alternately at intervals.

[0024] The first sub-gate 11 collects current in the first polarity region and the second sub-gate 12 collects current in the second polarity region, i.e., the first sub-gate 11 corresponds to the first polarity region and the second sub-gate 12 corresponds to the second polarity region.

[0025] The arrangement direction of the first main gate 13 and the second main gate 14 is different from the arrangement direction of the first sub-gate 11 and the second sub-gate 12, and the first main gate 13 is connected to the first sub-gate 11, and the second main gate 14 is connected to the second sub-gate 12, i.e., the first main gate 13 collects the current collected by the first sub-gate 11, and the second main gate 14 collects the current collected by the second sub-gate 12.

[0026] As shown in FIG. 6 , the plurality of first sub-gates 11 may include a first collection gate line 111 and a first merging gate line 112, and the first collection gate line 111 is cut at the position of the second main gate 14. The plurality of first main gates 13 include a first edge main gate 131 (i.e., the leftmost first main gate 13 in FIG. 6 ) located on the side closer to the first edge 101 of the back-contact solar cell 100, and a second main gate 14 (i.e., 6 ) is formed, one end of the first merging gate line 112 is connected to the first edge main gate 131, and the other end of the first merging gate line 112 passes through the first interruption region 140 to connect to the first main gate 13 adjacent to the first edge main gate 131 (i.e., the second first main gate 13 from left to right in FIG. 6 ), and the position of the first merging gate line 112 where it passes through the first interruption region 140 is insulated and isolated from the second main gate 14.

[0027] In the electrode structure 10, back-contact solar cell 100, battery module 200, and solar power generation system 1000 according to the embodiments of the present application, the first collection gate line 111 of the first sub-gate 11 is disconnected at the position of the second main gate 14, the first edge main gate 131 of the first main gate 13 is connected to the first collection gate line 111 in the first sub-gate 11 so as to collect current in the first polarity region near the first edge 101 by the first collection gate line 11, and the first merging gate line 112 passes through the first interrupted region 140 in the second main gate 14 adjacent to the first edge main gate 131 and is connected to the first edge main gate 131 and the first main gate 13 adjacent to the first edge main gate 131, and the current collected by the first edge main gate 131 is transmitted by the first merging gate line 112 to the first main gate 13 adjacent to the first edge main gate 131 to achieve merging, thereby completing the current collection. As a result, compared to the electrode pattern design of FIG. 2 in the background art, the first edge main gate 131 in the present application is located closer to the first edge 101 of the back-contact solar cell 100, and the current collected by the first edge main gate 131 in the edge region can directly merge with the first main gate 13 adjacent to the first edge main gate 131 via the first merging gate line 112. This eliminates the need for welding on the first edge main gate 131 to achieve edge region merging, avoiding stress concentration during the welding process and improving module yield and reliability. At the same time, compared to the electrode pattern design of FIG. 3 in the background art, the photo-generated electron-hole pairs located in the region near the first edge 101 in the present application can reach the opposite polarity region without long-distance diffusion, achieving current collection and fully ensuring high photoelectric conversion efficiency.

[0028] Specifically, in this embodiment, the polarities of the first polarity region and the second polarity region are opposite, and the polarities of the first sub-gate 11 and the second sub-gate 12 are also opposite. For example, the first sub-gate 11 is a positive sub-gate line that collects positive current from the positive polarity region, and the second sub-gate 12 is a negative sub-gate line that collects negative current from the negative polarity region. Alternatively, the first sub-gate 11 is a negative sub-gate line that collects negative current from the negative polarity region, and the second sub-gate 12 is a positive sub-gate line that collects positive current from the positive polarity region. The positive sub-gate line is located in a P-type doped region of the back-contact solar cell 100, and the negative sub-gate line is located in an N-type doped region of the back-contact solar cell 100.

[0029] As shown in Figure 6, in the embodiment shown in Figure 6, the first sub-gates 11 and the second sub-gates 12 are arranged alternately at intervals along the vertical direction, and the first sub-gates 11 and the second sub-gates 12 are both horizontal to the upper and lower edge lines of the back-contact solar cell 100, and correspondingly, the first polarity regions and the second polarity regions are also arranged alternately along the vertical direction.

[0030] The first main gate 13 and the second main gate 14 may be perpendicular to the first sub-gate 11 and the second sub-gate 12 and alternately arranged along the horizontal direction. For example, as shown in Figure 6, the first sub-gate 11 and the second sub-gate 12 are alternately arranged with a vertical gap between them, and both the first sub-gate 11 and the second sub-gate 12 are parallel to the top and bottom edge lines of the back-contact solar cell 100, while the first main gate 13 and the second main gate 14 are alternately arranged along the horizontal direction, and both the first main gate 13 and the second main gate 14 are parallel to the left and right edge lines of the back-contact solar cell 100.

[0031] In the present embodiment, the back contact solar cell 100 may be substantially rectangular. The substantially rectangular shape may be square, rectangular, or rectangular with standard corners, truncated corners, or rounded corners, depending on actual production needs and is not limited herein. The number of first sub-gates 11 and second sub-gates 12 is determined depending on the actual area of ​​the back contact solar cell 100 and the width and distance between the first sub-gates 11 and second sub-gates 12 and is not specifically limited herein.

[0032] In the embodiments of the present application, "the first interrupted region 130 is formed in the first edge main gate 131" means that the first edge main gate 131 has an interrupted structure and is divided at the position of the first interrupted region 130, i.e., the first interrupted region 130 divides the first edge main gate 131 into at least two parts.

[0033] In the embodiment shown in Figure 6, the "first edge 101" refers to the left edge in Figure 6, and "the first edge main gate 131 is located on the side closest to the first edge 101" means that the first edge main gate 131 is the leftmost first main gate 13 in Figure 6, i.e., the first first main gate 13 closest to the first edge 101, and may be at a certain distance from the first edge 101 of the back-contact solar cell 100, or may be located directly at the first edge 101 (i.e., the left edge in Figure 6) of the back-contact solar cell 100, and is not limited thereto.

[0034] As can be understood from FIG. 6 , in the embodiment of the present application, first sub-gates 11 and second sub-gates 12 are alternately arranged between a first edge main gate 131 and a second main gate 14 adjacent to the first edge main gate 131, and the first collection gate line 111 in the first sub-gate 11 between them is connected to the first edge main gate 131, the second sub-gate 12 is connected to the second main gate 14 adjacent to the first edge main gate 131, and the first merged gate line 112 passes through the first interrupted region 140 and is connected to the first main gate 13 adjacent to the first edge main gate 131.

[0035] The first edge main gate 131 can collect the current collected by the first collection gate line 111 between the first edge main gate 131 and the second main gate 14 adjacent to the first edge main gate 131, and then merge with the first main gate 13 adjacent to the first edge main gate 131 by the first merging gate line 112, thereby realizing the collection of the current generated in the first polarity region of the edge region near the first edge 101, and eliminating the need to weld on the first edge main gate 131 to achieve the merger, thereby avoiding the occurrence of cracks on the edge of the back-contact solar cell 100 during welding.

[0036] Furthermore, in the embodiment of the present application, the first sub-gate 11 and the second sub-gate 12 may be an aluminum gate line, a silver gate line, a copper gate line, or a silver-coated copper gate line, and are not limited here.

[0037] As will be appreciated, in the present embodiment, the first sub-gate 11 and the second sub-gate 12 can select gate lines of the same or different metal types, for example, the first sub-gate 11 and the second sub-gate 12 both select an aluminum gate line, or the first sub-gate 11 selects an aluminum gate line and the second sub-gate 12 selects a silver gate line.

[0038] If the first sub-gate 11 or the second sub-gate 12 is an aluminum gate line or a silver gate line, the aluminum gate line or the silver gate line can be printed in the doped region of the back-contact solar cell 100 by screen printing, and if the first sub-gate 11 or the second sub-gate 12 is a copper gate line, it is plated in the doped region of the back-contact solar cell 100 by electroplating, evaporation, etc.

[0039] Of course, in the embodiment of the present application, the first main gate 13 and the second main gate 14 may use gate lines of copper, silver, aluminum, silver-coated copper, etc., and are not limited thereto. As can be understood, when forming the first edge main gate 131, a screen printing plate may be used to cover the position corresponding to the first interrupted region 130, and then printing or electroplating and deposition may be performed to form the first edge main gate 131 having the first interrupted region 130.

[0040] In addition, in one preferred embodiment, the first merging gate line 112 is connected to the first edge main gate 131 and the first main gate 13 adjacent to the first edge main gate 131 to realize merging for the first edge main gate 131 and the adjacent first main gate 13. In order to reduce loss in the merging process, the first merging gate line 112 is preferably a copper gate line with low current loss, and other gate lines are not limited herein.

[0041] In an embodiment of the present application, a plurality of back-contact solar cells 100 in a battery module 200 can be sequentially connected in series to form a battery string, and each battery string can be connected in series, in parallel, or in a series-parallel combination to realize a combined current output. For example, a welding bar can be installed to realize a connection between each battery cell, and a bus bar can realize a connection between each battery string. For example, in the present application, a welding bar can be welded to all main gates other than the first edge main gate 131 and the second edge main gate 141 described later to realize a connection between each battery cell.

[0042] As will be appreciated, in the present embodiment, the battery module 200 may further include a metal frame, a back plate, a photovoltaic glass, and an adhesive film (none of which are shown). The adhesive film may be filled between the front surface of the back-contact solar cell 100 and the photovoltaic glass, between the back surface and the back plate, and between adjacent battery cells, etc. The filler may be a transparent adhesive with good light transmittance and degradation resistance. For example, the adhesive film may be an EVA adhesive film or a POE adhesive film. The specific adhesive film may be selected according to actual circumstances and is not limited herein.

[0043] The photovoltaic glass can cover an adhesive film on the front of the back-contact solar cell 100. The photovoltaic glass can be white plate glass, which has high light transmittance, high transparency, and excellent physical, mechanical, and optical properties. For example, the light transmittance of white plate glass can reach 92% or more, and can protect the back-contact solar cell 100 while minimizing its impact on the efficiency of the back-contact solar cell 100. At the same time, the adhesive film can bond the photovoltaic glass and the back-contact solar cell 100, and the adhesive film can provide sealing, insulation, and waterproofing and moisture protection for the back-contact solar cell 100.

[0044] A backplate may be attached to the adhesive film on the back of the back-contact solar cell 100, providing protection and support for the back-contact solar cell 100 and providing reliable insulation, water resistance, and degradation resistance. The backplate can be made of a variety of materials, including tempered glass, organic glass, and aluminum alloy TPT composite adhesive film. The specific backplate may be installed according to specific circumstances and is not limited thereto. The entire assembly consisting of the backplate, back-contact solar cell 100, adhesive film, and photovoltaic glass may be mounted on a metal frame, which serves as the main external support structure for the entire battery module 200 and provides stable support and mounting for the battery module 200. For example, the battery module 200 may be mounted in a predetermined position using the metal frame.

[0045] Furthermore, in this embodiment, the solar power generation system 1000 can be applied to solar power plants such as ground power plants, rooftop power plants, and water-based power plants, and can also be applied to facilities or devices that generate electricity using solar power, such as user solar power sources, solar street lights, solar cars, and solar buildings. Of course, it should be understood that the application scenarios of the solar power generation system 1000 are not limited thereto. That is, the solar power generation system 1000 can be applied to any field requiring solar power generation. Taking a solar power generation system network as an example, the solar power generation system 1000 may include a solar power generation array, a junction box, and an inverter. The solar power generation array may be a combination of an array of multiple battery modules 200. For example, the multiple battery modules 200 may constitute multiple solar power generation arrays. The solar power generation arrays are connected to the junction box, which can combine currents generated by the solar power generation arrays. The combined current is converted to AC required by the utility grid via an inverter and then connected to the utility grid, thereby realizing solar power supply.

[0046] In some embodiments, the first edge main gate 131 may be located at the first edge 101 of the back contact solar cell 100. Specifically, "the first edge main gate 131 is located at the first edge 101" is understood to mean that the first edge main gate 131 is installed at the edge line of the first edge 101 of the back contact solar cell 100, or that no separate sub-gate is installed between the first edge main gate 131 and the edge line of the back contact solar cell 100.

[0047] Example 2 6, in some embodiments, no weld is provided on the first edge main gate 131. In this way, welding can be performed without providing a weld on the first edge main gate 131, thereby saving material for the weld and reducing costs, and avoiding cracks on the edge during welding.

[0048] In some embodiments, the first edge main gate 131 is not used for welding, which can avoid cracks caused by welding at the edge.

[0049] As will be understood, in such a case, the first edge main gate 131 may not have a weld and may not be used for welding, or the first edge main gate 131 may have a weld but not be used for welding, and preferably the first edge main gate 131 may not have a weld and may not be used for welding.

[0050] Example 3 In some embodiments, the number of first merging gate lines 112 may be multiple, the number of first interruption regions 140 may be multiple, and each first interruption region 140 corresponds to at least one first merging gate line 112.

[0051] In this way, the first edge main gate 131 and the first main gate 13 adjacent to the first edge main gate 131 are connected by the multiple first merging gate lines 112, thereby improving merging efficiency.

[0052] Specifically, in this embodiment, preferably, one first interrupted region 140 corresponds to one first merging gate line 112. In this way, the width of the first interrupted region 140 is too large, which can prevent welding defects (e.g., soldering defects) from occurring when welding the first edge main gate 131 on the second main gate 14 in a subsequent process, thereby ensuring the reliability of the welding.

[0053] 6 shows only one first merging gate line 112 and some sub-gates and main gates of the electrode structure, but this is merely an example for explanatory purposes. It should be understood that in some embodiments, a plurality of first sub-gates 11, second sub-gates 12, and a plurality of first merging gate lines 112 may be further installed below the first merging gate line 112 in FIG. 6, and the specific number thereof may be determined according to the size of the back-contact solar cell 100 and is not limited here.

[0054] Example 4 In some embodiments, the number of first merging gate lines 112 may be multiple, and the multiple first merging gate lines 112 are arranged symmetrically along the center line of the back-contact solar cell 100 in the arrangement direction of the first sub-gates 11 and the second sub-gates 12.

[0055] In this way, by symmetrically arranging the multiple first merging gate lines 112, the merging paths of each first merging gate line 112 when collecting current from the first edge main gate 131 can be made approximately the same, and it is possible to avoid a situation where a large difference in the merging paths causes different losses in different paths, which affects the merging effect and increases the overall loss.

[0056] Specifically, in this embodiment, the multiple first merging gate lines 112 are arranged symmetrically along the center line of the back-contact solar cell 100 in the arrangement direction of the first sub-gates 11 and the second sub-gates 12. That is, the first merging gate lines 112 arranged in the two symmetrical regions above and below the back-contact solar cell 100 are symmetrical, and the distance between the connection points of each first merging gate line 112 and the first edge main gate 131 is the same. In this way, when merging, the merging paths that merge with each first merging gate line 112 through the first edge main gate 131 are approximately the same, and the losses are the same, which ensures the merging effect and improves the merging efficiency.

[0057] Of course, it should be understood that in some embodiments, the number of first merging gate lines 112 may be one, and the one first merging gate line 112 may be located at the center position of the back-contact solar cell 100, i.e., the connection point between the one first merging gate line 112 and the first edge main gate 131 is located at the midpoint position of the first edge main gate 131.

[0058] In this way, by using one first merging gate line 112 installed at the center, the merging paths of the currents collected by the first collecting gate lines 111 can be made almost the same, which avoids large overall losses due to large differences in the merging paths and ensures the merging effect.

[0059] Specifically, in this embodiment, one first merging gate line 112 is connected to the midpoint of the first edge main gate 131, so that the back-contact solar cell 100 can be divided into two symmetrical regions, one above the other. In this way, the merging paths of the currents collected by the first collecting gate lines 111 in the two upper and lower regions at the first edge main gate 131 are basically the same, ensuring the merging effect.

[0060] Example 5 In some embodiments, the width of the first merging gate line 112 may be 80 μm to 1.5 mm.

[0061] In this way, by setting the width of the first merging gate line 112 within a reasonable range of 80 μm to 1.5 mm, the merging effect of the first merging gate line 112 can be ensured, and it is possible to avoid the first merging gate line 112 being unable to withstand the current merged from the first edge main gate 131 due to the width of the first merging gate line 112 being too small, which could result in the first merging gate line 112 overheating and even melting, and it is also possible to avoid the waste of slurry due to the width of the first merging gate line 112 being too wide.

[0062] Specifically, in such an embodiment, the width of the first merging gate line 112 may be 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, or any value between 80 μm and 1.5 mm, and is not limited here.

[0063] Furthermore, in some embodiments, the width of the first merging gate line 112 is preferably greater than 1.5 times the width of the first collecting gate line 111 .

[0064] In this way, by setting the width of the first merging gate line 112 to be 1.5 times larger than the width of the first collection gate line 111, the merging effect and reliability can be guaranteed.

[0065] Specifically, as can be understood, in the embodiment of the present application, the current flowing through the first merging gate line 112 is the current after being merged by the first edge main gate 131, so the width of the first merging gate line 112 is preferably greater than 1.5 times the width of the first collection gate line 111, to ensure that the first merging gate line 112 has a wide width and thereby ensure the reliability of the merging.

[0066] In some embodiments, the spacing between two second sub-gates 12 adjacent to the first merging gate line 112 is larger than the spacing between other adjacent second sub-gates 12 .

[0067] In this way, by setting the distance between the two second sub-gates 12 adjacent to the first merging gate line 112 large, the width of the first merging gate line 112 can be set wide, thereby ensuring the merging effect and reliability.

[0068] Example 6 As shown in FIG. 6 , in some embodiments, a plurality of first welds 142 are spaced apart on the second main gate 14 adjacent to the first edge main gate 131; The first interrupted region 140 is located between two adjacent first welds 142 .

[0069] In this way, by installing the first interrupted region 140 at two adjacent first welding portions 142, a merging function can be realized and the integrity of the first welding portion 142 can be guaranteed, thereby ensuring the welding function of the second main gate 14 adjacent to the first edge main gate 131.

[0070] Specifically, in such an embodiment, the plurality of first welds 142 may be uniformly distributed at intervals on the second main gate 14 adjacent to the first edge main gate 131 (FIG. 6 shows only two first welds 142 for illustrative purposes), the number of first interrupted regions 140 between two adjacent first welds 142 is preferably one, and the number of first merging gate lines 112 corresponding to the first interrupted regions 140 is preferably one. In this way, by having at least one first merging gate line 112 between every two first welds 142, the number and width of the first interrupted regions 140 between two adjacent first welds 142 can be reduced, and the welding of the second main gate 14 adjacent to the first edge main gate 131 can be avoided.

[0071] In such an embodiment, the distance between two adjacent first welds 142 in the second main gate 14 adjacent to the first edge main gate 131 may be greater than 5 mm, and preferably greater than 9 mm. In some embodiments, in order to reduce the amount of slurry used for the first welds 142 of the same size, the distance between two adjacent first welds 142 may be set to greater than 11 mm and equal to or less than 45 mm.

[0072] Furthermore, in such an embodiment, the distance between two adjacent first welds 142 is more preferably greater than 11 mm and equal to or less than 30 mm. By setting the distance between the first welds 142 within this optimum range, the number of first welds 142 can be guaranteed, which prevents welding defects from occurring during welding, ensures welding reliability, and prevents high costs due to an excessive number of first welds 142.

[0073] Of course, as shown in FIG. 7, in some embodiments, the first interrupted region 140 may be formed at the first weld 142, i.e., the first interrupted region 140 is formed at the first weld 142.

[0074] In this way, one first interrupted region 140 is formed in each first welded portion 142, and the first interrupted region 140 is uniformly arranged, and the first merging gate line 112 is also uniformly arranged, thereby ensuring the merging effect.

[0075] Specifically, as shown in FIG. 7 , in such a case, the first weld 142 may be divided into two spaced apart opposing portions by a first interrupted region 140, the first interrupted region 140 being preferably located at the center of the first weld 142, and the first merging gate line 112 passing through the center of the first weld 142 to connect the first edge main gate 131 and the first main gate 13 adjacent to the first edge main gate 131, thereby realizing merging with the first edge main gate 131.

[0076] In such a case, in order to avoid the effect of the first intermittent region 140 formed in the first welded portion 142 affecting the subsequent welding effect, the length of the first welded portion 142 can be set to be long or the width of the first welded portion 142 can be set to be wide, thereby ensuring the reliability of the subsequent welding.

[0077] Example 7 Furthermore, as shown in FIG. 6 , in some embodiments, the first interrupted region 140 may be located between two adjacent first welds 142, and the distance between the first merging gate line 112 passing through the first interrupted region 140 and the center line between the two adjacent first welds 142 is 20 mm or less, i.e., the distance between the first merging gate line 112 and the midpoint between the two adjacent first welds 142 is 20 mm or less.

[0078] In this way, the first merging gate line 112 can be kept at an appropriate distance from the first welding portion 142, which avoids the problem of poor soldering when welding the first welding portion 142 due to the presence of the first merging gate line 112.In addition, the first merging gate line 112 can be kept at an appropriate distance from the center between the two first welding portions 142, which prevents the merging paths of the currents merging at the first collection gate lines 111 on both the upper and lower sides of the first merging gate line 112 from differing significantly, which does not affect the merging effect.

[0079] As can be seen, in some embodiments, during printing, the height of the first merging gate line 112 is the same as the height of the first welding portion 142, or even slightly higher than the height of the first welding portion 142. The distance between the first merging gate line 112 and the first welding portion 142 should not be too small; if it is too small, there will be a certain height difference between the first merging gate line 112 and the first welding portion 142, which will easily cause soldering defects during welding. Therefore, the distance between the first merging gate line 112 and the center line between two adjacent first welding portions 142 is 20 mm or less, which can effectively prevent soldering defects and an increase in the defect rate caused by a too small distance between the first welding portion 142 and the first merging gate line 112.

[0080] At the same time, if the distance between the first merging gate line 112 and the center line between the two first welds 142 is too large, there will be a large difference in the merging path when the first merging gate line 112 merges from both the upper and lower sides, and the corresponding loss will also be large, which will affect the merging effect. Therefore, if the distance between the first merging gate line 112 and the center line between two adjacent first welds 142 is 20 mm or less, the merging effect of the first merging gate line 112 can be effectively guaranteed.

[0081] Furthermore, in this embodiment, the distance between the first merging gate line 112 passing through the first interrupted region 140 and the center line between two adjacent first welds 142 may be 10 mm or less. In this manner, by setting the distance between the first merging gate line 112 and the centers between the two first welds 142 within this preferred range, the merging effect can be effectively ensured.

[0082] In this embodiment, the first interrupted region 140 is located between two adjacent first welds 142, and the distance between the first merging gate line 112 passing through the first interrupted region 140 and the center line between the two adjacent first welds 142 is preferably 5 mm or less, more preferably 3 mm or less, and most preferably 1 mm. In this way, the position of the first merging gate line 112 can be aligned as closely as possible with the center line between the two first welds 142, ensuring that the merging paths from the top and bottom directions are approximately the same, thereby ensuring the merging effect.

[0083] Specifically, in this embodiment, ideally, the first merging gate line 112 can be disposed on the center line between two adjacent first welds 142. That is, the first merging gate line 112 overlaps the center line between two adjacent first welds 142, with the distance between them being zero. In this way, the paths in each direction are completely the same, and the merging effect is optimal. Of course, in some embodiments, the distance between the first merging gate line 112 passing through the first interrupted region 140 and the center line between two adjacent first welds 142 may be a value such as 1 mm, 0.8 mm, 0.6 mm, 0.4 mm, 0.2 mm, or 0.1 mm. Specifically, the distance is not limited here, and is most preferably zero.

[0084] Example 8 As shown in FIG. 8, in some embodiments, the first interrupted region 140 may be coated with a first insulating layer 15.

[0085] In this way, by covering the first interrupted region 140 with the first insulating layer 15, it is possible to prevent the welding bar from coming into contact with the first merging gate line 112 when welding the first welding portion 142, thereby preventing leakage of electricity.

[0086] Specifically, to achieve insulation, the size of the first insulating layer 15 may be equal to or slightly larger than the size of the first interruption region 140, that is, only the region of the second main gate 14 corresponding to the first interruption region 140 is covered with the first insulating layer 15, and the other regions are not covered with the first insulating layer 15. The first insulating layer 15 may be an insulating adhesive.

[0087] Example 9 9 and 10 , in some embodiments, the second sub-gate 12 may include a first interrupted gate line 123 adjacent to the first merging gate line 112 and a first curved gate line 124 adjacent to the first interrupted gate line 123, and the first interrupted gate line 123 includes a first connecting section 1231 and a second connecting section 1232 spaced apart, and a first gap is formed between the first connecting section 1231 and the second connecting section 1232; The first connection section 1231 is connected to the second main gate 14 adjacent to the first edge main gate 131, the second connection section 1232 is connected to the first curved gate line 124 and surrounds the end of the first collection gate line 111 between the first interrupted gate line 123 and the first curved gate line 124, and the first collection gate line 111 located between the first interrupted gate line 123 and the first curved gate line 124 is not connected to the first edge main gate 131 and is connected to the first merging gate line 112 via the first through gate line 125 that penetrates the first gap.

[0088] In this way, by connecting the first curved gate line 124 and the first connection section 1231, the first collection gate line 111 between the first interrupted gate line 123 and the first curved gate line 124 can be surrounded, and the first through gate line passes through the first gap to connect the first merging gate line 112 and the surrounded first collection gate line 111, thereby realizing merging for the first collection gate line 111 that is not connected to the first edge main gate 131.

[0089] Specifically, as shown in FIG. 9 , in the embodiment shown in FIG. 9 , the first interrupted gate line 123 is adjacent to the first merging gate line 112, and the first curved gate line 124 may be located at the upper left corner of the back-contact solar cell 100. The first merging gate line 112 may pass through the first weld 142, i.e., the first interrupted region 140 is located at the first weld 142, and the end of the first curved gate line 124 is curved toward the first merging gate line 112. The first curved gate line 124 is connected to the second connecting section 1232 of the first interrupted gate line 123, and the first curved gate line 124 and the second connecting section 1232 surround the first collection gate line 111 adjacent to the first curved gate line 124, and the first collection gate line 111 surrounded by the first curved gate line 124 is not connected to the first edge main gate 131 but is connected to the first merging gate line 112 via the first through gate line 125 penetrating the first gap, thereby realizing merging. It should be understood that in this embodiment, the shape of the second polarity region corresponding to the first curved gate line 124 can match the shape of the first curved gate line 124.

[0090] Also, as shown in FIG. 10, in the embodiment shown in FIG. 10, the first curved gate line 124 may be located at the middle position of the back-contact solar cell 100, and the first interrupted region 140 is located between two adjacent first welds 142, and the specifics are not limited here. Of course, in other embodiments, the first curved gate line 124 may be located at any other position of the back-contact solar cell 100, and the number of the first curved gate line 124 and the first interrupted gate line 123 may be one or more, and the specifics are not limited here.

[0091] Example 10 As shown in FIG. 11 , in some embodiments, the electrode structure 10 may further include a first merging electrode 16 located adjacent to the first edge main gate 131, where no welding portion is provided on the first merging electrode 16, the first merging electrode 16 is closer to the first edge 101 than the first edge main gate 131, and the first merging electrode 16 is connected to the second sub-gate 12 located between the first edge main gate 131 and the first merging electrode 16, i.e., the polarity of the first merging electrode 16 is the same as the polarity of the second sub-gate 12 and the second main gate 14.

[0092] The electrode structure 10 further includes a first connecting gate line 17 located at the ends of the first main gate 13 and the second main gate 14, and the first connecting gate line 17 is not cut at the position of the first edge main gate 131, and the first connecting gate line 17 is connected to the first merging electrode 16 and the second main gate 14 adjacent to the first edge main gate 131.

[0093] In this way, by placing the first merging electrode 16 at a position closer to the first edge 101 than the first edge main gate 131, the current collected by the second sub-gate 12 located in the vicinity of the first edge 101 can be collected and merged into the second main gate 14 adjacent to the first edge main gate 131 via the first connecting gate line 17. This eliminates the need to perform welding on the first merging electrode 16 to achieve merging, thereby preventing cracks from occurring due to stress concentration when welding at the edge. It also eliminates the need to set the sub-gates in the edge region to the same polarity as in Figure 3 in the background art, thereby avoiding a decrease in photoelectric conversion performance.

[0094] Specifically, as shown in FIG. 11, the first merging electrode 16 and the second main gate 14 have the same polarity, and a second sub-gate 12 (i.e., a second sub-gate 12 located in the vicinity of the first edge 101) cut at the position of the first edge main gate 131 is installed between the second merging electrode 19 and the first edge main gate 131, and the second merging electrode 19 can merge the current collected by the second sub-gate 12 located in the edge region into the adjacent second main gate 14 via the first connecting gate line 17.

[0095] Furthermore, as shown in FIG. 11, in some embodiments, the number of first connecting gate lines 17 is two, and the two first connecting gate lines 17 are located at both ends of the first main gate 13 and the second main gate 14, respectively.

[0096] In this way, the two first connecting gate lines 17 realize uniform merging with the second sub-gate 12 in the edge region close to the first edge 101, and it is possible to avoid a decrease in efficiency due to the merging path being too long.

[0097] Specifically, as shown in FIG. 11 , two first connection gate lines 17 may be respectively connected to both ends of the first merging electrode 16 and to both ends of the adjacent second main gate 14, that is, the first connection gate line 17, the first merging electrode 16 and the adjacent second main gate 14 together surround the first edge main gate 131 and the sub-gate between the first edge main gate 131 and the first merging electrode 16.

[0098] 11 , in some embodiments, the distance between a first edge main gate 131 and a second main gate 14 adjacent to the first edge main gate 131 may be smaller than the distance between other adjacent first main gates 13 and second main gates 14. That is, in such cases, the first main gates 13 and second main gates 14 do not have to be arranged at uniform intervals, the distance between the first edge main gate 131 and the adjacent second main gate 14 may be set small, and a sub-gate may or may not be provided between them, and this is not limited here.

[0099] In some embodiments, the first merging electrode 16 is located at the first edge 101. Specifically, "the first merging electrode 16 is located at the first edge 101" is understood to mean that the first merging electrode 16 is located at the edge line of the back-contact solar cell 100, or that no separate sub-gate is located between the first merging electrode 16 and the edge line of the back-contact solar cell 100.

[0100] Example 11 In some embodiments, the width of the first connecting gate line 17 is between 80 μm and 1.5 mm.

[0101] In this way, by setting the width of the first connecting gate line 17 within a reasonable range of 80 μm to 1.5 mm, the merging effect of the first connecting gate line 17 can be ensured, and it is possible to avoid the first connecting gate line 17 being unable to withstand the current merged from the first merging electrode 16 due to the width of the first connecting gate line 17 being too small, which could result in the first connecting gate line 17 overheating and even melting, and it is also possible to avoid the waste of slurry due to the width of the first connecting gate line 17 being too wide.

[0102] Specifically, in such an embodiment, the width of the first connection gate line 17 may be 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, or any value between 80 μm and 1.5 mm, and is not limited here.

[0103] Furthermore, in some embodiments, the width of the first connecting gate line 17 is preferably greater than 1.5 times the width of the second sub-gate 12 .

[0104] In this way, by setting the width of the first connection gate line 17 to be greater than 1.5 times the width of the second sub-gate 12, it is possible to ensure the merging effect and reliability of the merging.

[0105] Specifically, as can be understood, in the embodiment of the present application, the current flowing through the first connecting gate line 17 is the current after being merged by the first merging gate line 112, so the width of the first connecting gate line 17 is preferably greater than 1.5 times the width of the second gate 11, which can ensure that the first connecting gate line 17 has a wide width to ensure the reliability of the merging.

[0106] Example 12 Further, as shown in FIG. 6 , in some embodiments, the second main gate 14 may include a second edge main gate 141 (i.e., the rightmost second main gate 14 in FIG. 6 ) located closer to the second edge 102 (i.e., the right edge in FIG. 6 ) of the back contact solar cell 100, where the second edge 102 and the first edge 101 face each other, The plurality of second sub-gates 12 may include a second collection gate line 121 and a second merging gate line 122, the second collection gate line 121 being cut at the position of the first main gate 13, a second interrupted region 130 being formed in the first main gate 13 adjacent to the second edge main gate 141 (i.e., the first first main gate 13 from right to left in FIG. 6 ), and the second merging gate line 122 having one end connected to the second edge main gate 141 and the other end passing through the second interrupted region 130 and connected to the second main gate 14 adjacent to the second edge main gate 141 (i.e., the second second main gate 14 from right to left in FIG. 6 ).

[0107] In this way, the second collection gate line 121 of the second sub-gate 12 is disconnected at the position of the first main gate 13, the second edge main gate 141 of the second main gate 14 is connected to the second collection gate line 121 in the second sub-gate 12 to collect current in the second polarity region near the second edge 102, and the second merging gate line 122 passes through the second interruption region 130 of the first main gate 13 adjacent to the second edge main gate 141 and is connected to the second edge main gate 141 and the second main gate 14 adjacent to the second edge main gate 141, and the current collected by the second edge main gate 141 is transmitted to the second main gate 14 adjacent to the second edge main gate 141 via the second merging gate line 122 to achieve merging and complete the current collection. In this way, the second edge main gate 141 is located closer to the first edge 101 of the back-contact solar cell 100, and the first edge main gate 131 can be directly connected and merged with the adjacent first main gate 13 via the first merging gate line 112. Compared to the electrode pattern design in Figure 2 of the background art, there is no need to weld on the first edge main gate 131 to achieve merging in the edge region near the second edge 102, which avoids the problem of stress concentration during the welding process and improves module yield and reliability. Furthermore, compared to the third type of electrode pattern design in the background art, photo-generated electron-hole pairs can reach the opposite polarity region without long-distance diffusion, realizing current collection and fully ensuring high photoelectric conversion efficiency.

[0108] In the illustrated embodiment, "second edge 102" refers to the right edge in FIG. 6, and "the second edge main gate 141 is located closer to the second edge 102" means that the second edge main gate 141 is the rightmost second main gate 14 in FIG. 6, i.e., the first second main gate 141 closest to the second edge 102, and may be at a certain distance from the second edge 102 of the back-contact solar cell 100, or may be located directly at the second edge 102 (i.e., the right edge in FIG. 6) of the back-contact solar cell 100, and is not limited thereto.

[0109] In the embodiments of the present application, "the second interrupted region 140 is formed in the second edge main gate 141" means that the second edge main gate 141 has an interrupted structure and is divided at the position of the second interrupted region 140, i.e., the second interrupted region 140 divides the second edge main gate 141 into at least two parts.

[0110] Similarly, as will be understood, when forming the second edge main gate 141, a screen plate can be used to cover the position corresponding to the second interrupted region 140, and then printing or electroplating and deposition can be performed to form the second edge main gate 141 having the second interrupted region 140.

[0111] Also, as shown in FIG. 6 , as can be understood, in the embodiment of the present application, first sub-gates 11 and second sub-gates 12 are alternately installed between the second edge main gate 141 and the first main gate 13 adjacent to the second edge main gate 141, the second collection gate line 121 in the second sub-gate 12 is connected to the second edge main gate 141, the first sub-gate 11 is connected to the first main gate 13 adjacent to the second edge main gate 141, and the second merging gate line 122 passes through the second interrupted region 130 in the first main gate 13 adjacent to the second edge main gate 141 and is connected to the first main gate 13 adjacent to the second edge main gate 141.

[0112] The second edge main gate 141 can collect the current collected by the second collection gate line 121 between the second edge main gate 141 and the first main gate 13 adjacent to the second edge main gate 141, and then merge with the second main gate 14 adjacent to the second edge main gate 141 by the second merging gate line 122, thereby realizing the collection of the current generated in the second polarity region in the vicinity of the second edge 10, and eliminating the need to weld on the second edge main gate 141 to achieve the merger, thereby avoiding the occurrence of cracks at the edge of the back-contact solar cell 100 during welding.

[0113] Similarly, similar to the first merging gate line 112, in some embodiments, the second merging gate line 122 is connected to the second edge main gate 141 and the second main gate 14 adjacent to the second edge main gate 141 to realize merging with the second edge main gate 141 and the adjacent first main gate 13, so preferably the second merging gate line 122 uses a copper gate line with low current loss.

[0114] In some embodiments, the second edge main gate 141 may be located at the second edge 102 of the back contact solar cell 100. Specifically, "the second edge main gate 141 is located at the second edge 102" is understood to mean that the second edge main gate 141 is located at the edge line of the back contact solar cell 100, or that no separate sub-gate is located between the second edge main gate 141 and the edge line of the back contact solar cell 100.

[0115] Example 13 Furthermore, similar to the first edge main gate 131, in some embodiments, the second edge main gate 141 may not require a weld. In this manner, welding can be performed without requiring a weld on the second edge main gate 141, thereby saving material for the weld, reducing costs, and avoiding cracks on the edge during welding.

[0116] In some embodiments, the second edge main gate 141 is not used for welding, which can prevent cracks from occurring due to welding at the edge.

[0117] As will be understood, in such a case, the second edge main gate 141 may not have a weld and may not be used for welding, or the second edge main gate 141 may have a weld but not be used for welding, and preferably the second edge main gate 141 may not have a weld and may not be used for welding.

[0118] Example 14 In some embodiments, like the first merging gate lines 112, the number of second merging gate lines 122 may be multiple, the number of second interruption regions 130 may be multiple, and each second interruption region 130 corresponds to at least one second merging gate line 122.

[0119] In this way, the second edge main gate 141 and the second main gate 14 adjacent to the second edge main gate 141 are connected by the plurality of second merging gate lines 122, thereby improving merging efficiency.

[0120] Specifically, in this embodiment, preferably, one second interrupted region 130 corresponds to one second merging gate line 122, and thus, the width of the second interrupted region 130 is too large, which can prevent welding defects (e.g., soldering defects) from occurring when welding on the second main gate 14 adjacent to the second edge main gate 141 in a subsequent process, thereby ensuring the reliability of the welding.

[0121] 6 shows only one second merging gate line 122 and some sub-gates and main gates of the electrode structure, but this is merely an example for explanatory purposes. It should be understood that in some embodiments, a plurality of first sub-gates 11, second sub-gates 12, and a plurality of second merging gate lines 122 may be further installed below the second merging gate line 122 in FIG. 6, and the specific number thereof may be determined according to the size of the back-contact solar cell 100 and is not limited here.

[0122] Example 15 In some embodiments, the number of second merging gate lines 122 may be multiple, and the multiple second merging gate lines 122 are arranged symmetrically along the center line of the back-contact solar cell 100 in the arrangement direction of the first sub-gates 11 and the second sub-gates 12.

[0123] In this way, by symmetrically arranging the multiple second merging gate lines 122, the merging paths through which each second merging gate line 122 collects current from the second edge main gate 141 can be made approximately the same, which avoids a situation where the losses in different paths are different due to large differences in the merging paths, resulting in an increase in overall loss, and ensures the merging effect.

[0124] Specifically, in this embodiment, the second merging gate lines 122 are arranged symmetrically along the center line of the back-contact solar cell 100 in the arrangement direction of the first sub-gates 11 and the second sub-gates 12. That is, the second merging gate lines 122 arranged in the two symmetrical regions above and below the back-contact solar cell 100 are symmetrical, and the distance between the connection points of each second merging gate line 122 and the second edge main gate 141 is the same. In this way, when merging, the merging paths that merge with each second merging gate line 122 through the second edge main gate 141 are approximately the same, and the losses are the same, which ensures the merging effect and improves the merging efficiency.

[0125] Of course, it should be understood that in some embodiments, the number of second merging gate lines 122 may be one, and the single second merging gate line 122 may be located at the center position of the back-contact solar cell 100, i.e., the connection point between the single second merging gate line 122 and the second edge main gate 141 is located at the midpoint position of the second edge main gate 141.

[0126] In this way, by using one second merging gate line 122 installed at the center, the merging paths of the currents collected by the second collecting gate lines 121 can be made almost the same, which avoids large overall losses due to large differences in the merging paths and ensures the merging effect.

[0127] Specifically, in this embodiment, one second merging gate line 122 is connected to the midpoint of the second edge main gate 141, so that the back-contact solar cell 100 can be divided into two symmetrical regions, one above the other. In this way, the merging paths of the currents collected by the second collecting gate lines 121 in the two upper and lower regions at the second edge main gate 141 are basically the same, ensuring the merging effect.

[0128] Example 16 In some embodiments, the width of the second merging gate line 122 may be 80 μm to 1.5 mm.

[0129] In this way, by setting the width of the second merging gate line 122 within a reasonable range of 80 μm to 1.5 mm, the merging effect of the second merging gate line 122 can be ensured, and it is possible to avoid the second merging gate line 122 being unable to withstand the current merged from the second edge main gate 141 due to the width of the second merging gate line 122 being too small, which could result in the second merging gate line 122 overheating and even melting, and it is also possible to avoid the second merging gate line 122 being too wide, which would result in wasting slurry.

[0130] Specifically, in such an embodiment, the width of the second merging gate line 122 may be 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, or any value between 80 μm and 1.5 mm, and is not limited thereto.

[0131] Furthermore, in some embodiments, the width of the second merging gate line 122 is preferably greater than 1.5 times the width of the second collecting gate line 121 .

[0132] In this way, by setting the width of the second merging gate line 122 to be 1.5 times larger than the width of the second collection gate line 121, the merging effect and reliability can be guaranteed.

[0133] Specifically, as can be understood, in the embodiment of the present application, the current flowing through the second merging gate line 122 is the current after being merged by the second edge main gate 141, so the width of the second merging gate line 122 is preferably greater than 1.5 times the width of the first collection gate line 111, to ensure that the second merging gate line 122 has a wide width and thereby ensure the reliability of the merging.

[0134] In some embodiments, the distance between two first sub-gates 11 adjacent to the second merging gate line 122 is larger than the distance between other adjacent first sub-gates 11.

[0135] In this way, by setting the distance between the two first sub-gates 11 adjacent to the second merging gate line 122 large, the width of the second merging gate line 122 can be set wide, thereby ensuring the merging effect and reliability of the merging.

[0136] Example 17 As shown in FIG. 6 , in some embodiments, a plurality of second welds 132 are spaced apart on the first main gate 13 adjacent to the second edge main gate 141; The second interrupted region 130 is located between two adjacent second welds 132 .

[0137] In this way, by installing the second interrupted region 130 at two adjacent second welding portions 132, a merging function can be realized and the integrity of the second welding portion 132 can be guaranteed, thereby ensuring the welding function of the first main gate 13 adjacent to the second edge main gate 141.

[0138] Specifically, in this embodiment, the plurality of second welds 132 may be uniformly distributed at intervals on the first main gate 13 adjacent to the second edge main gate 141, the number of second interrupted regions 130 between two adjacent second welds 132 is preferably one ( FIG. 6 exemplarily shows only two first welds 142), and the number of second merging gate lines 122 corresponding to the second interrupted regions 130 is preferably one. In this way, by having at least one second merging gate line 122 between every two second welds 132, the number and width of the second interrupted regions 130 between two adjacent second welds 132 can be reduced, and the welding of the first main gate 13 adjacent to the second edge main gate 141 can be avoided.

[0139] In such an embodiment, the distance between two adjacent second welds 132 in the first main gate 13 adjacent to the second edge main gate 141 may be greater than 5 mm, and preferably greater than 9 mm. In some embodiments, in order to reduce the amount of slurry used for the second welds 132 of the same size, the distance between two adjacent second welds 132 may be set to greater than 11 mm and equal to or less than 45 mm.

[0140] Furthermore, in such an embodiment, the distance between two adjacent second welds 132 is more preferably greater than 11 mm and equal to or less than 30 mm. By setting the distance between the second welds 132 within this optimum range, the number of second welds 132 can be guaranteed, which prevents welding defects from occurring during welding, ensures welding reliability, and prevents high costs due to an excessive number of second welds 132.

[0141] Of course, as shown in FIG. 12, in some embodiments, the second interrupted region 130 may be formed at the second weld 132, i.e., the second interrupted region 130 is formed at the second weld 132.

[0142] In this way, one second interrupted region 130 is formed in each second weld 132, and the second interrupted region 130 is uniformly arranged, and the second merging gate line 122 is also uniformly arranged, which similarly ensures the merging effect.

[0143] Specifically, as shown in FIG. 12, in such a case, the second weld 132 may be divided into two spaced apart opposing portions by the second interrupted region 130, and the second interrupted region 130 is preferably located at the center of the second weld 132, and the second merging gate line 122 passes through the center of the second weld 132 to connect the second edge main gate 141 and the second main gate 14 adjacent to the second edge main gate 141 to realize the merging.

[0144] In such a case, in order to avoid the effect of the second intermittent region 130 being formed in the second welded portion 132 affecting the subsequent welding effect, the length of the second welded portion 132 can be set to be long or the width of the second welded portion 132 can be set to be wide, thereby ensuring the reliability of the subsequent welding.

[0145] Example 18 Furthermore, as shown in FIG. 6 , in some embodiments, the second interrupted region 130 may be located between two adjacent second welds 132, and the distance between the second merging gate line 122 passing through the second interrupted region 130 and the center line between the two adjacent second welds 132 is 20 mm or less, i.e., the distance between the second merging gate line 122 and the midpoint between the two adjacent second welds 132 is 20 mm or less.

[0146] In this way, the second merging gate line 122 can be kept at an appropriate distance from the second welding portion 132, which avoids the problem of poor soldering when welding the second welding portion 132 due to the presence of the second merging gate line 122. At the same time, the second merging gate line 122 can be kept at an appropriate distance from the center between the two second welding portions 132, which prevents the merging paths of the currents merging at the first collection gate lines 111 on both the upper and lower sides of the second merging gate line 122 from differing significantly, thereby not affecting the merging effect.

[0147] As can be seen, in some embodiments, during printing, the height of the second merging gate line 122 is the same as the height of the second welding portion 132, or even slightly higher than the height of the second welding portion 132. The distance between the second merging gate line 122 and the second welding portion 132 should not be too small; otherwise, there will be a certain height difference between the second merging gate line 122 and the second welding portion 132, which will easily cause soldering defects during welding. Therefore, the distance between the second merging gate line 122 and the center line between two adjacent second welding portions 132 is set to 20 mm or less, which can effectively prevent soldering defects and an increase in the defect rate caused by a too small distance between the second welding portion 132 and the second merging gate line 122.

[0148] At the same time, if the distance between the second merging gate line 122 and the center line between two adjacent second welds 132 is too large, there will be a large difference in the merging path when the second merging gate line 122 merges from both the upper and lower sides, and the corresponding loss will also be large, which will affect the merging effect. Therefore, if the distance between the second merging gate line 122 and the center line between two adjacent second welds 132 is 20 mm or less, the merging effect of the second merging gate line 122 can be effectively guaranteed.

[0149] Furthermore, in this embodiment, the distance between the second merging gate line 122 passing through the second interrupted region 130 and the center line between two adjacent second welds 132 is 10 mm or less. Thus, by setting the distance between the second merging gate line 122 and the centers between the two second welds 132 within this preferred range, the merging effect can be effectively ensured.

[0150] In this embodiment, the second interrupted region 130 is located between two adjacent second welds 132, and the distance between the second merging gate line 122 passing through the second interrupted region 130 and the center line between the two adjacent second welds 132 is preferably 5 mm or less, more preferably 3 mm or less, and most preferably 1 mm. In this way, the position of the second merging gate line 122 can be aligned as closely as possible with the center line between the two second welds 132, ensuring that the merging paths from each direction are approximately the same and ensuring the merging effect.

[0151] Specifically, in this embodiment, ideally, the second merging gate line 122 can be disposed on the center line between two adjacent second welds 132. That is, the second merging gate line 122 overlaps the center line between two adjacent second welds 132, with the distance between them being zero. In this way, the paths in each direction are completely the same, and the merging effect is optimal. Of course, in some embodiments, the distance between the second merging gate line 122 passing through the second interrupted region 130 and the center line between two adjacent second welds 132 may be 1 mm, 0.8 mm, 0.6 mm, 0.4 mm, 0.2 mm, 0.1 mm, etc., and is not particularly limited thereto. Most preferably, the distance is zero.

[0152] Example 19 As shown in FIG. 8, in some embodiments, the second interrupted region 130 may be coated with a second insulating layer 18.

[0153] In this way, by covering the second interrupted region 130 with the second insulating layer 18, it is possible to prevent the welding bar from coming into contact with the second merging gate line 122 when welding the second welding portion 132, thereby preventing leakage of electricity.

[0154] Specifically, to achieve insulation, the size of the second insulating layer 18 may be equal to or slightly larger than the size of the second interruption region 130, that is, only the region of the first main gate 13 corresponding to the second interruption region 130 is covered with the second insulating layer 18, and the other regions are not covered with the second insulating layer 18. The second insulating layer 18 may be an insulating adhesive.

[0155] Example 20 13 , in some embodiments, the second sub-gate 12 may include a second interrupted gate line 113 adjacent to the second merging gate line 122 and a second curved gate line 114 adjacent to the second interrupted gate line 113, and the second interrupted gate line 113 includes a third connecting section 1131 and a fourth connecting section 1132 spaced apart, and a second gap is formed between the third connecting section 1131 and the fourth connecting section 1132; The third connection section 1131 is connected to the first main gate 13 adjacent to the second edge main gate 141, the fourth connection section 1132 is connected to the second curved gate line 114 and surrounds the end of the second collection gate line 121 between the second interrupted gate line 113 and the second curved gate line 114, and the second collection gate line 121 located between the second interrupted gate line 113 and the second curved gate line 114 is not connected to the second edge main gate 141 and is connected to the second merging gate line 122 via the second through gate line 115 that penetrates the second gap.

[0156] In this way, by connecting the second curved gate line 114 and the third connection section 1131, the second collection gate line 121 between the second interrupted gate line 113 and the second curved gate line 114 can be surrounded, and the second through gate line 115 passes through the second gap to connect the second merging gate line 122 and the surrounded second collection gate line 121, thereby realizing merging with the second collection gate line 121 that is not connected to the second edge main gate 141.

[0157] 13 , the second interrupted gate line 113 may be adjacent to the second merging gate line 122, and the second curved gate line 114 may be located at the middle of the back-contact solar cell 100. The end of the second curved gate line 114 may be curved toward the second merging gate line 122 and connected to the fourth connecting section 1132 of the second interrupted gate line 113. The second curved gate line 114 and the fourth connecting section 1132 surround the second collection gate line 121 adjacent to the second curved gate line 114. The second collection gate line 121 surrounded by the second curved gate line 114 is not connected to the second edge main gate 141 but is connected to the second merging gate line 122 via the second through gate line 115 that penetrates the second gap, thereby achieving merging. As will be understood, in such an embodiment, the shape of the first polarity region corresponding to the second curved gate line 114 may match the shape of the second curved gate line 114.

[0158] In addition, in some embodiments, the second curved gate line 114 may be located at any other position of the back contact solar cell 100, and the number of the second curved gate line 114 and the second interrupted gate line 113 may be one or more, and is not limited here.

[0159] Example 21 As shown in FIG. 14 , in some embodiments, the electrode structure 10 may further include a second merging electrode 19 located adjacent to the second edge main gate 141, where no welding portion is located on the second merging electrode 19, the second merging electrode 19 is closer to the second edge 102 than the second edge main gate 141, and the second merging electrode 19 is connected to the first sub-gate 11 located between the second edge main gate 141 and the second merging electrode 19, i.e., the polarity of the second merging electrode 19 is the same as the polarity of the first sub-gate 11 and the first main gate 13.

[0160] The electrode structure 10 further includes a second connecting gate line 21 located at the ends of the first main gate 13 and the second main gate 14, and the second connecting gate line 21 is not cut at the position of the second edge main gate 141, and the second connecting gate line 21 is connected to the second merging electrode 19 and the first main gate 13 adjacent to the second edge main gate 141.

[0161] In this way, by placing the second merging electrode 19 at a position closer to the second edge 102 than the second edge main gate 141, the current collected by the first sub-gate 11 located in the vicinity of the second edge 102 can be collected and merged into the first main gate 13 adjacent to the second edge main gate 141 via the second connecting gate line 21. This eliminates the need to perform welding on the second merging electrode 19 to achieve merging, thereby preventing cracks from occurring due to stress concentration when welding at the edge. It also eliminates the need to set the sub-gates in the edge region to the same polarity as in Figure 3 in the background art, thereby avoiding a decrease in photoelectric conversion performance.

[0162] Specifically, as shown in FIG. 14, the second merging electrode 19 and the first main gate 13 have the same polarity, and a first sub-gate 11 (i.e., a first sub-gate 11 located in the vicinity of the second edge 102) cut at the position of the second edge main gate 141 is installed between the second merging electrode 19 and the second edge main gate 141, and the second merging electrode 19 can merge the current collected by the first sub-gate 11 located in the edge region into the adjacent first main gate 13 via the second connecting gate line 21.

[0163] Furthermore, as shown in FIG. 14, in some embodiments, the number of second connecting gate lines 21 is two, and the two second connecting gate lines 21 are located at both ends of the first main gate 13 and the second main gate 14, respectively.

[0164] In this way, the two second connection gate lines 21 can realize uniform merging with the first sub-gate 11 in the edge region, and it is possible to avoid a decrease in efficiency due to the merging path being too long.

[0165] Specifically, as shown in FIG. 14, two second connection gate lines 21 may be respectively connected to both ends of the second merging electrode 19 and to both ends of the adjacent first main gate 13, that is, the second connection gate line 21, the second merging electrode 19 and the adjacent first main gate 13 together surround the second edge main gate 141 and the sub-gate between the second edge main gate 141 and the second merging electrode 19.

[0166] 14, in some embodiments, the distance between a second edge main gate 141 and a first main gate 13 adjacent to the second edge main gate 141 is smaller than the distance between another adjacent second main gate 14 and the first main gate 13. In other words, in such cases, the first main gate 13 and the second main gate 14 do not have to be arranged at uniform intervals, the distance between the second edge main gate 141 and the adjacent first main gate 13 may be set small, and a sub-gate may or may not be provided between them, and this is not limited here.

[0167] In some embodiments, the second merging electrode 19 is located at the second edge 102. Specifically, "the second merging electrode 19 is located at the second edge 102" is understood to mean that the second merging electrode 19 is located at the edge line of the back-contact solar cell 100, or that no separate sub-gate is located between the second merging electrode 19 and the edge line of the back-contact solar cell 100.

[0168] Example 22 In some embodiments, the width of the second connecting gate line 21 is between 80 μm and 1.5 mm.

[0169] In this way, by setting the width of the second connection gate line 21 within a reasonable range of 80 μm to 1.5 mm, the merging effect of the second connection gate line 21 can be guaranteed, and it is possible to avoid the second connection gate line 21 being unable to withstand the current merged from the second merging electrode 19 due to the second connection gate line 21 being too small, which could result in the second connection gate line 21 overheating and even melting, and it is also possible to avoid the second connection gate line 21 being too wide, which could result in wasting slurry.

[0170] Specifically, in such an embodiment, the width of the second connection gate line 21 may be 80 μm, 100 μm, 200 μm, 300 μm, 400 μm, 500 μm, 600 μm, 700 μm, 800 μm, 900 μm, 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, or any value between 80 μm and 1.5 mm, and is not limited here.

[0171] Furthermore, in some embodiments, the width of the second connecting gate line 21 is preferably greater than 1.5 times the width of the first sub-gate 11 .

[0172] In this way, by setting the width of the second connection gate line 21 to be greater than 1.5 times the width of the first sub-gate 11 (for example, the first collection gate line 111), it is possible to ensure the merging effect and the reliability of the merging.

[0173] Specifically, as can be understood, in the embodiment of the present application, the current flowing through the second connecting gate line 21 is the current after being merged by the second merging gate line 122, so the width of the second connecting gate line 21 is preferably greater than 1.5 times the width of the first sub-gate 11, which can ensure that the second connecting gate line 21 has a wide width to ensure the reliability of the merging.

[0174] Table 1 below compares the measured performance of a back-contact solar cell using the electrode patterns in FIGS. 2 and 3 with that of a back-contact solar cell using the electrode structure of the present invention.

[0175] [Table 1]

[0176] Comparative Example 1 in Table 1 uses the electrode pattern shown in Figure 2, and Comparative Example 2 uses the electrode pattern shown in Figure 3. As is well known, cell conversion efficiency is an important performance evaluation index for back-contact solar cells, with higher values ​​indicating better performance. Even a 0.1% improvement is considered a breakthrough in the industry. As can be seen from Table 1, the technique shown in Figure 2 achieves high efficiency but suffers from reliability issues with its edge welding, resulting in reduced yield. On the other hand, the technique shown in Figure 3 solves the module yield and reliability issues, but significantly reduces performance, with an overall conversion efficiency of only 18.3% and a loss in efficiency due to the edge region of 0.788%. By using the technical means of the present application, the overall conversion efficiency can reach 25.95%, which is much higher than the conversion efficiency in Comparative Example 2, while balancing module yield and reliability. At the same time, the technical means of the present application can reduce the efficiency loss due to the presence of the edge region to 0.023%. However, since the reproducibility of conversion efficiency measurements for current back contact solar cells is approximately ±0.05%, this efficiency loss is virtually undetectable and can be ignored.

[0177] As can be seen, the technical solutions of the present application can solve the problems of module yield and reliability, ensure the overall efficiency of the back contact solar cell, and at the same time reduce the efficiency loss in the edge region.

[0178] In the description herein, references to terms such as "some embodiments," "exemplary embodiments," "examples," "specific examples," or "some examples" mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. General references to such terms in the description herein do not necessarily refer to the same embodiment or example. Furthermore, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.

[0179] Furthermore, the above description is merely a preferred embodiment of the present application and does not limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should be included within the protection scope of the present application.

Claims

1. 1. An electrode structure for use in a back-contact solar cell, the back-contact solar cell including alternating first and second polarity regions; the electrode structure includes a plurality of first sub-gates and a plurality of second sub-gates spaced apart from one another, the first sub-gates collecting current in the first polarity region and the second sub-gates collecting current in the second polarity region; the electrode structure further includes a plurality of first main gates and a plurality of second main gates alternately arranged at intervals, an arrangement direction of the first main gates and the second main gates is different from an arrangement direction of the first sub-gates and the second sub-gates, the first main gates are connected to the first sub-gates, and the second main gates are connected to the second sub-gates; the plurality of first sub-gates include a first collection gate line and a first merging gate line, the first collection gate line being disconnected at the position of the second main gate, the plurality of first main gates include a first edge main gate disposed near a first edge of the back-contact solar cell, a first interruption region is formed in the second main gate adjacent to the first edge main gate, and the first merging gate line has one end connected to the first edge main gate and the other end passing through the first interruption region and connected to the first main gate adjacent to the first edge main gate; The first edge main gate has no welds and / or is not used for welding; The first edge main gate is located at the first edge.

2. 2. The electrode structure of claim 1, wherein the number of the first merging gate lines is plural, the number of the first interruption regions is plural, and each of the first interruption regions corresponds to at least one of the first merging gate lines.

3. The number of the first merging gate lines is plural, and the first merging gate lines are arranged symmetrically along the center line of the back-contact solar cell in the arrangement direction of the first sub-gates and the second sub-gates, or 2. The electrode structure according to claim 1, wherein the number of the first merging gate lines is one, and the one first merging gate line is located at a center position of the back-contact solar cell.

4. The width of the first merging gate line is 80 μm to 1.5 mm; and / or The electrode structure of claim 1 , wherein the width of the first merging gate line is greater than 1.5 times the width of the first collection gate line.

5. a plurality of first welds are provided at intervals on the second main gate adjacent to the first edge main gate; 2. The electrode structure according to claim 1, wherein the first interrupted region is located between two adjacent first welded portions, or the first interrupted region is formed in the first welded portion.

6. 6. The electrode structure according to claim 5, wherein the first interrupted region is located between two adjacent first welds, and the number of the first interrupted regions between two adjacent first welds is one.

7. 6. The electrode structure according to claim 5, wherein the first interruption region is located between two adjacent first welds, and a distance between the first merging gate line passing through the first interruption region and a center line between the two adjacent first welds is 20 mm or less.

8. 8. The electrode structure according to claim 7, wherein a distance between the first merging gate line passing through the first interrupted region and a center line between two adjacent first welds is 10 mm or less.

9. 9. The electrode structure according to claim 8, wherein a distance between the first merging gate line passing through the first interrupted region and a center line between two adjacent first welds is 5 mm or less.

10. 10. The electrode structure according to claim 9, wherein a distance between the first merging gate line passing through the first interrupted region and a center line between two adjacent first welds is 3 mm or less.

11. a first insulating layer is coated on the first interrupted region; and / or 2. The electrode structure according to claim 1, wherein a distance between two of the second sub-gates adjacent to the first merging gate line is larger than a distance between other adjacent second sub-gates.

12. the second sub-gate includes a first interrupted gate line adjacent to the first merging gate line and a first curved gate line adjacent to the first interrupted gate line, the first interrupted gate line includes a first connection section and a second connection section spaced apart, and a first gap is formed between the first connection section and the second connection section; 2. The electrode structure of claim 1, wherein the first connection section is connected to the second main gate adjacent to the first edge main gate, the second connection section is connected to the first curved gate line and surrounds an end of the first collection gate line between the first interrupted gate line and the first curved gate line, and the first collection gate line located between the first interrupted gate line and the first curved gate line is not connected to the first edge main gate and is connected to the first merging gate line via a first through gate line passing through the first gap.

13. the electrode structure further includes a first merging electrode disposed adjacent to the first edge main gate, the first merging electrode having no weld, the first merging electrode being closer to the first edge than the first edge main gate, and the first merging electrode being connected to the second sub-gate located between the first edge main gate and the first merging electrode; 2. The electrode structure of claim 1, further comprising a first connection gate line located at an end of the first main gate and the second main gate, the first connection gate line not being cut at the position of the first edge main gate, and the first connection gate line being connected to the first merging electrode and the second main gate adjacent to the first edge main gate.

14. the number of the first connection gate lines is two, and the two first connection gate lines are located at both ends of the first main gate and the second main gate, respectively; and / or 14. The electrode structure of claim 13, wherein a distance between the first edge main gate and the second main gate adjacent to the first edge main gate is smaller than a distance between another adjacent first main gate and the second main gate.

15. The electrode structure according to claim 13 , wherein the first joining electrode is located at the first edge.

16. the width of the first connecting gate line is between 80 μm and 1.5 mm; and / or The electrode structure of claim 13 , wherein the width of the first connecting gate line is greater than 1.5 times the width of the second sub-gate.

17. the second main gate includes a second edge main gate disposed near a second edge of the back contact solar cell, the second edge and the first edge facing each other; 2. The electrode structure of claim 1, wherein the plurality of second sub-gates include a second collection gate line and a second merging gate line, the second collection gate line being cut at the position of the first main gate, a second interruption region being formed in the first main gate adjacent to the second edge main gate, and one end of the second merging gate line being connected to the second edge main gate and the other end being connected to the second main gate adjacent to the second edge main gate through the second interruption region.

18. The second edge main gate has no welds and / or is not used for welding; 20. The electrode structure of claim 17, wherein the second edge main gate is located at a second edge of the back contact solar cell.

19. 18. The electrode structure of claim 17, wherein the number of the second merging gate lines is plural, the number of the second interruption regions is plural, and each of the second interruption regions corresponds to at least one of the second merging gate lines.

20. The number of the second merging gate lines is plural, and the second merging gate lines are arranged symmetrically along the center line of the back-contact solar cell in the arrangement direction of the first sub-gates and the second sub-gates; or 18. The electrode structure according to claim 17, wherein the number of the second merging gate lines is one, and the one second merging gate line is located at a center position of the back-contact solar cell.

21. The width of the second merging gate line is 80 μm to 1.5 mm; and / or 18. The electrode structure of claim 17, wherein the width of the second merging gate line is greater than 1.5 times the width of the second collection gate line.

22. a plurality of second welds are provided at intervals on the first main gate adjacent to the second edge main gate; 18. The electrode structure according to claim 17, wherein the second interrupted region is located between two adjacent second welds, or the second welds have the second interrupted region formed therein.

23. 23. The electrode structure according to claim 22, wherein the second interrupted region is located between two adjacent second welds, and the number of the second interrupted regions between two adjacent second welds is one.

24. 23. The electrode structure of claim 22, wherein the second interruption region is located between two adjacent second welds, and a distance between the second merging gate line passing through the second interruption region and a center line between the two adjacent second welds is 20 mm or less.

25. 25. The electrode structure according to claim 24, wherein a distance between the second merging gate line passing through the second interrupted region and a center line between two adjacent second welds is 10 mm or less.

26. 26. The electrode structure of claim 25, wherein a distance between the second merging gate line passing through the second interrupted region and a center line between two adjacent second welds is 5 mm or less.

27. The second interrupted region is coated with a second insulating layer; and / or The electrode structure according to claim 17 , wherein a distance between two of the first sub-gates adjacent to the second merging gate line is larger than a distance between other adjacent first sub-gates.

28. the first sub-gate includes a second interrupted gate line adjacent to the second merging gate line and a second curved gate line adjacent to the second interrupted gate line, the second interrupted gate line includes a third connection section and a fourth connection section spaced apart from each other, and a second gap is formed between the third connection section and the fourth connection section; 18. The electrode structure of claim 17, wherein the third connection section is connected to the first main gate adjacent to the second edge main gate, the fourth connection section is connected to the second curved gate line and surrounds an end of the second collection gate line between the second interrupted gate line and the second curved gate line, and the second collection gate line located between the second interrupted gate line and the second curved gate line is not connected to the second edge main gate and is connected to the second merging gate line via a second through gate line passing through the second gap.

29. the electrode structure further includes a second merging electrode disposed adjacent to the second edge main gate, the second merging electrode having no weld, the second merging electrode being closer to the second edge than the second edge main gate, and the second merging electrode being connected to the first sub-gate located between the second edge main gate and the second merging electrode; 18. The electrode structure of claim 17, further comprising a second connection gate line located at an end of the first main gate and the second main gate, the second connection gate line not being cut at the position of the second edge main gate, and the second connection gate line being connected to the second merging electrode and the first main gate adjacent to the second edge main gate.

30. the number of the second connection gate lines is two, and the two second connection gate lines are located at both ends of the first main gate and the second main gate, respectively; and / or 30. The electrode structure of claim 29, wherein a distance between the second edge main gate and the first main gate adjacent to the second edge main gate is smaller than a distance between another adjacent second main gate and the first main gate.

31. The electrode structure of claim 29 , wherein the second confluence electrode is located at the second edge.

32. the width of the second connecting gate line is between 80 μm and 1.5 mm; and / or 30. The electrode structure of claim 29, wherein the width of the second connecting gate line is greater than 1.5 times the width of the first sub-gate.

33. 33. A back contact solar cell comprising the electrode structure of any one of claims 1 to 32, wherein the electrode structure is disposed on a back side of the back contact solar cell.

34. 34. A battery module comprising the back contact solar cell of claim 33.

35. A solar power generation system comprising the battery module according to claim 34.

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