Photovoltaic module

Abstract

The present application discloses a photovoltaic module, comprising: a plurality of cells, wherein each cell has a first side edge and a second side edge; the cell is provided with an electrode structure; the electrode structure comprises a plurality of fingers; the fingers are at least partially parallel to the first side edge; in an extension direction of the second side edge, two types of fingers having opposite polarities are alternately arranged; in an extension direction of the first side edge, each finger comprises a plurality of second notches and a plurality of connecting portions, the second notches and the connecting portions are arranged adjacent to each other, and the plurality of second notches divide the finger into a plurality of sections, wherein the second notches are of a discontinuous void structure; and a plurality of tabbing ribbons, wherein the tabbing ribbons are arranged in the extension direction of the second side edge and configured to connect adjacent cells in series, each tabbing ribbon is electrically connected to connecting portions of fingers having one polarity, and the tabbing ribbon is at least partially in contact with the surface of the cell at second notches of fingers having the other polarity. The present application can reduce the amount of insulating adhesive used, lower the insulating adhesive costs, and shorten processing time.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS The present application claims priority to the Chinese patent application filed with the China National Intellectual Property Administration on May 28, 2024, with application number 202410676883.1 and entitled "SOLAR CELL, PHOTOVOLTAIC MODULE, AND METHOD FOR MANUFACTURING PHOTOVOLTAIC MODULE", the entire contents of which are incorporated herein by reference. TECHNICAL FIELD The present application relates to the field of photovoltaic cells, and in particular, to a photovoltaic module. BACKGROUND In the photovoltaic cell industry, when interconnect ribbons are used to string two adjacent solar cells together, to ensure reliable insulation performance between the interconnect ribbons and the fingers of opposite polarity, an insulating adhesive is usually printed on a surface of the solar cell to insulate the interconnect ribbons from the fingers. However, the current design of the electrode structure on the surface of the solar cell requires a relatively large amount of insulating adhesive to achieve insulation between the interconnect ribbons and the fingers of opposite polarity, resulting in an increase in both the material cost of the photovoltaic module and the manufacturing process time. SUMMARY An object of embodiments of the present application is to provide a photovoltaic module, aiming to solve the problem that conventional photovoltaic modules consume a relatively large amount of insulating adhesive. To solve the above technical problem, the present application is implemented as follows: A photovoltaic module, including: a plurality of solar cells, each of the solar cells including a first side and a second side; the solar cell being provided with an electrode structure, the electrode structure including a plurality of fingers, the fingers being at least partially parallel to the first side, and along an extending direction of the second side, fingers of opposite polarities being alternately arranged; along an extending direction of the first side, each of the fingers including a plurality of second gaps and a plurality of connecting portions, the second gaps and the connecting portions being adjacently arranged, the plurality of second gaps dividing the finger into a plurality of segments, where each of the second gaps is an interrupted structure; and along the extending direction of the first side and the extending direction of the second side, the second gaps and the connecting portions being adjacently arranged; and a plurality of interconnect ribbons, each of the interconnect ribbons being arranged along the extending direction of the second side to connect adjacent solar cells in series; any one of the interconnect ribbons being electrically connected to the connecting portions of the fingers of one polarity, and at positions corresponding to the second gaps of the fingers of the other polarity, the interconnect ribbon being at least partially in contact with a surface of the solar cell. In the embodiments of the present application, by designing the second gaps in the fingers on the surface of the solar cell, some of the insulating adhesive at the second gaps can be omitted. From the perspective of the entire solar cell and the photovoltaic module, more insulating adhesive can be saved, which helps to reduce the cost of the insulating adhesive. Meanwhile, since a large amount of insulating adhesive is no longer applied at the second gaps, some process time can be saved, the manufacturing time of the photovoltaic module can be shortened, and the throughput of the photovoltaic module can be improved. Moreover, the removal of some of the insulating adhesive at the second gaps also helps to reduce the height difference between the top of the interconnect ribbon and the top of the finger, which is conducive to reducing the internal stress of the laminate and improving the product quality of the photovoltaic module. In addition, when the interconnect ribbons are arranged for string soldering, the interconnect ribbons can be soldered to the connecting portions of the fingers of the corresponding polarity. Compared with the soldering design between the interconnect ribbons and the fingers, the connecting portions can provide a larger soldering area than the fingers, providing a greater adhesion force for the interconnect ribbons, so that the connection between the interconnect ribbons and the solar cells is more reliable. Moreover, the larger soldering area is also conducive to reducing the soldering resistance, thereby reducing the power loss of the solar cells. The above description is only an overview of the technical solutions of the present application. To more clearly understand the technical means of the present application and to implement them in accordance with the contents of the description, and to make the above and other objects, features, and advantages of the present application more apparent and understandable, specific implementations of the present application are set forth below. BRIEF DESCRIPTION OF THE DRAWINGS To more clearly illustrate the technical solutions in the embodiments of the present application or in the related art, the following briefly introduces the accompanying drawings required for use in the description of the embodiments or the related art. Apparently, the accompanying drawings in the following description are some embodiments of the present application, and for a person of ordinary skill in the art, other accompanying drawings can be obtained based on these accompanying drawings without creative efforts. FIG. 1 is a first schematic structural diagram of a solar cell according to an embodiment of the present application. FIG. 2 is a schematic diagram showing positions of connecting portions of a solar cell according to an embodiment of the present application. FIG. 3 is a schematic diagram showing connection between a solar cell and an interconnect ribbon according to an embodiment of the present application. FIG. 4 is a schematic diagram showing a gap formed between an interconnect ribbon and an insulating adhesive according to an embodiment of the present application. FIG. 5 is a schematic diagram showing no gap formed between an interconnect ribbon and an insulating adhesive according to an embodiment of the present application. FIG. 6 is a schematic diagram showing overlapping of an interconnect ribbon and an insulating adhesive according to an embodiment of the present application. FIG. 7 is a schematic diagram showing a finger being continuously integral at a connecting portion according to an embodiment of the present application. FIG. 8 is a schematic diagram showing a width of an interconnect ribbon at a connecting portion being greater than a width of the interconnect ribbon at a second gap according to an embodiment of the present application. FIG. 9 is a first partial structural schematic diagram of a solar cell according to an embodiment of the present application. FIG. 10 is a second partial structural schematic diagram of a solar cell according to an embodiment of the present application. FIG. 11 is a third partial structural schematic diagram of a solar cell according to an embodiment of the present application. FIG. 12 is a schematic diagram showing a complete layout of an electrode structure on a surface of a solar cell according to an embodiment of the present application. FIG. 13 is a partial enlarged schematic view of position I in FIG. 12 according to an embodiment of the present application. FIG. 14 is a second schematic structural diagram of a solar cell according to an embodiment of the present application. FIG. 15 is a third schematic structural diagram of a solar cell according to an embodiment of the present application. FIG. 16 is a fourth schematic structural diagram of a solar cell according to an embodiment of the present application. FIG. 17 is a first schematic diagram of a shape of a connecting portion according to an embodiment of the present application. FIG. 18 is a second schematic diagram of a shape of a connecting portion according to an embodiment of the present application. FIG. 19 is a third schematic diagram of a shape of a connecting portion according to an embodiment of the present application. Description of Reference Numerals: solar cell - 10, first side - 10a, second side - 10b, electrode structure - 101, first gap - 102b, second gap - 102a, interconnect ribbon - 103, connecting portion - 104, first unipolar unit - 105, finger - 1011, positive finger - 1011a, negative finger - 1011b, end busbar - 1012, middle busbar - 1013, edge busbar - 1014, insulating adhesive - 1015, first connecting portion - 1016, second connecting portion - 1017, edge interconnect ribbon at left edge - 1031, and edge interconnect ribbon at right edge - 1032. DETAILED DESCRIPTION To make the objects, technical solutions, and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. Apparently, the described embodiments are some, rather than all, of the embodiments of the present application. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments of the present application without creative efforts shall fall within the protection scope of the present application. The terms "first", "second", and the like in the description and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. The data so used may be interchanged under appropriate circumstances so that the embodiments of the present application can be implemented in sequences other than those illustrated or described herein. In addition, in the description and the claims, "and / or" means at least one of the connected objects, and the character " / " generally indicates that the associated objects are in an "or" relationship. In the description of the present application, the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", and the like indicating orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings, and are used only for convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and should not be construed as limiting the present application. In the description of the present application, unless otherwise explicitly specified and defined, the terms such as "mount", "connect", and "connection" should be understood in a broad sense. For example, the connection may be a fixed connection, a detachable connection, or an integral connection; a mechanical connection or an electrical connection; or a direct connection, or an indirect connection through an intermediate medium, or an internal communication between two elements. For a person of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances. The photovoltaic module provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios thereof. In the photovoltaic module according to the embodiments of the present application, the electrode structure on the surfaces of the solar cells constituting the cell string is optimized and improved, so that during string soldering, when the interconnect ribbons pass through certain positions on the surfaces of the solar cells, a large amount of insulating adhesive is no longer applied for insulation, thereby reducing the consumption of the insulating adhesive. Compared with conventional photovoltaic modules, since a large amount of insulating adhesive is no longer required at certain positions on the surfaces of the solar cells, the cost of the insulating adhesive is naturally reduced, and the time originally required for adhesive application can also be saved, which helps to improve the manufacturing efficiency of the photovoltaic module. As shown in FIG. 1, which is a schematic structural diagram of a solar cell used in a photovoltaic module according to an embodiment of the present application, a solar cell 10 may be a silicon wafer made of monocrystalline silicon or polycrystalline silicon. The solar cell 10 may have a rectangular shape with a first side 10a and a second side 10b. The first side 10a and the second side 10b may be two sides of the rectangular silicon wafer perpendicular to each other. For example, the first side 10a may be a long side of the rectangle, and the second side 10b may be a short side of the rectangle. An extending direction of the first side 10a is the X direction as shown in the figure, and an extending direction of the second side 10b is the Y direction as shown in the figure. An electrode structure 101 is disposed on a surface of the solar cell 10. Exemplarily, the electrode structure 101 may be prepared by screen printing or electroplating. The electrode structure 101 includes a plurality of fingers 1011 distributed on the solar cell 10. The fingers 1011 are generally relatively thin and may also be referred to as fine grid lines. These fingers 1011 may include fingers of opposite polarities, one being positive fingers 1011a and the other being negative fingers 1011b. As shown in FIG. 1, all of the fingers 1011 may be partially or entirely parallel to the first side 10a, and along the extending direction Y of the second side 10b, the positive fingers 1011a and the negative fingers 1011b may be alternately arranged. As shown in FIG. 1 and FIG. 2, FIG. 2 shows a surface structure of the solar cell after the connecting portions 104 are formed based on FIG. 1. In the embodiments of the present application, for both the positive fingers 1011a and the negative fingers 1011b, along the extending direction X of the first side 10a, the finger 1011 includes a plurality of second gaps 102a and a plurality of connecting portions 104 (refer to FIG. 2 for the connecting portions 104). The second gap 102a is an interrupted structure. At the position of the second gap 102a, no conductive medium is present, so that the finger 1011 is interrupted and divided into a plurality of segments. At the position of the connecting portion 104, the finger 1011 remains electrically coupled. Exemplarily, the connecting portion 104 may be a pad. Along the first side 10a, the second gap 102a and the connecting portion 104 are adjacently arranged on the same finger 1011, and the second gap 102a and the connecting portion 104 may each be located at two ends of the same segment of the finger 1011. Further, along the extending direction of the second side 10b, the second gaps 102a and the connecting portions 104 on two adjacent fingers 1011 are adjacently arranged. In conjunction with the description of the above embodiments, in the embodiments of the present application, when counting the number of the fingers 1011, grid lines that overlap in the X direction are regarded as the same finger 1011. The portions of the same finger 1011 separated by the second gaps 102a are different segments of the finger 1011. As shown in FIG. 2, along the X direction, the finger 1011 forms a structural configuration of "grid line - connecting portion - grid line - second gap - grid line - connecting portion - grid line - second gap - grid line - connecting portion - grid line". In the actual processing and manufacturing of such a solar cell, the connecting portions 104 and the fingers 1011 may be formed by printing in the same process step, or may be formed by printing in different process steps in stages. FIG. 3 also shows a schematic diagram of interconnect ribbons 103 laid on a surface of one solar cell when a plurality of interconnect ribbons 103 are used for string soldering. The interconnect ribbons 103 are each arranged along the extending direction of the second side 10b to connect the solar cells 10 adjacently arranged in the Y direction in series. As shown in FIG. 3, when any one of the interconnect ribbons 103 is laid along the Y direction as shown in the figure, the connecting portions 104 of the fingers 1011 of one polarity are electrically connected together. When the interconnect ribbon 103 passes through the second gaps 102a of the fingers 1011 of the other polarity, the interconnect ribbon remains insulated from the fingers 1011 of the other polarity. Along the extending direction of the second side 10b (i.e., the Y direction), which is also the extending direction of the interconnect ribbons 103, the connecting portions 104 on at least one finger 1011 and the second gaps 102a on another finger 1011 are alternately arranged. For example, in FIG. 2, along the Y direction, the connecting portions 104 on the positive fingers 1011a and the second gaps 102a on the negative fingers 1011b are alternately arranged. Accordingly, along the Y direction, a structural feature of "connecting portion - second gap - connecting portion - second gap - connecting portion -second gap" is formed. Due to the design of the second gaps 102a, the interconnect ribbons 103 are already insulated from the fingers 1011 of the other polarity. Therefore, at the second gaps 102a, the interconnect ribbons 103 are at least partially in contact with the surface of the solar cell 10. That is to say, at the second gaps 102a, a large amount of insulating adhesive is no longer required to be applied, so that the interconnect ribbons 103 are at least partially in direct contact with the solar cell 10. The interconnect ribbon 103 may include a core material and a solder layer such as a tin alloy layer on the outer periphery. At the second gap 102a, the interconnect ribbon 103 is in contact with a passivation layer (e.g., a silicon nitride layer, an aluminum oxide layer, etc.) and a TCO layer of the solar cell 10. There may be no electrode structure and no insulating adhesive between the interconnect ribbon 103 and the solar cell 10. Therefore, in the embodiments of the present application, by designing the second gaps in the fingers on the surface of the solar cell, some of the insulating adhesive at the second gaps can be omitted. From the perspective of the entire solar cell and the photovoltaic module, more insulating adhesive can be saved, which helps to reduce the cost of the insulating adhesive. Meanwhile, since a large amount of insulating adhesive is no longer applied at the second gaps, some process time can be saved, the manufacturing time of the photovoltaic module can be shortened, and the throughput of the photovoltaic module can be improved. Moreover, the removal of some of the insulating adhesive at the second gaps also helps to reduce the height difference between the top of the interconnect ribbon and the top of the finger, which is conducive to reducing the internal stress of the laminate and improving the product quality of the photovoltaic module. In addition, when the interconnect ribbons are arranged along the Y direction for string soldering, the interconnect ribbons can be soldered to the connecting portions of the fingers of the corresponding polarity. Compared with the soldering design between the interconnect ribbons and the fingers, the connecting portions can provide a larger soldering area than the fingers, providing a greater adhesion force for the interconnect ribbons, so that the connection between the interconnect ribbons and the solar cells is more reliable. Moreover, the larger soldering area is also conducive to reducing the soldering resistance, thereby reducing the power loss of the solar cells. In some embodiments, when laying the interconnect ribbons 103, to prevent short circuits caused by accidental contact between the interconnect ribbons 103 and the fingers 1011 adjacent to the second gaps 102a due to deviation of the interconnect ribbons 103, a small amount of insulating adhesive 1015 may also be applied at the second gaps 102a to further improve insulation reliability. Specifically, within an allowable range of process tolerances, when the interconnect ribbons 103 deviate to different extents, the interconnect ribbons 103 and the insulating adhesive 1015 in the photovoltaic module may form the following different positional relationships: a) As shown in FIG. 4, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), when the interconnect ribbon 103 deviates to a relatively small extent, the interconnect ribbon 103 may still maintain a certain gap from the insulating adhesive 1015. In this case, along a thickness direction Z of the solar cell 10, there is no insulating adhesive 1015 between the interconnect ribbon 103 and the solar cell 10, and the interconnect ribbon 103 is completely in direct contact with the solar cell 10. In this case, the physical insulation distance between the interconnect ribbon 103 and the fingers 1011 of the opposite polarity is relatively large, providing good insulation performance. b) As shown in FIG. 5, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), when the interconnect ribbon 103 deviates to a relatively large extent, the interconnect ribbon 103 just contacts an edge of the insulating adhesive 1015, and along the X direction, there is no gap between the interconnect ribbon 103 and the insulating adhesive 1015. In this case, along the thickness direction Z of the solar cell 10, there is still no insulating adhesive 1015 between the interconnect ribbon 103 and the solar cell 10, and the interconnect ribbon 103 is in direct contact with the solar cell 10. In this case, even if the interconnect ribbon 103 deviates, under the insulating and isolating effect of the insulating adhesive 1015, the interconnect ribbon 103 and the fingers 1011 of the opposite polarity can still have good insulation performance. In actual production, certain process tolerances inevitably exist. In this case, a main body portion of the interconnect ribbon 103 is in direct contact with the solar cell 10, and an edge portion of the interconnect ribbon 103 partially overlaps with the insulating adhesive 1015 (as shown in FIG. 6). Such an overlapping configuration can still ensure insulation performance within the allowable range of process tolerances. In some embodiments, as shown in FIG. 1 and FIG. 2, in the solar cell according to the embodiments of the present application, along the extending direction X of the first side 10a, the finger 1011 further includes a plurality of first gaps 102b. Similar to the second gaps 102a in the foregoing embodiments, at the position of the first gap 102b, the finger 1011 may also be a disconnected and discontinuous structure. However, since the interconnect ribbon 103 needs to be electrically connected to the fingers 1011 of the same polarity at the position where the first gap 102b is located, the connecting portion 104 is provided at the position of the first gap 102b, and the connecting portion 104 can connect and electrically couple segments of the disconnected fingers 1011. Accordingly, when the interconnect ribbon 103 is soldered to the connecting portion 104, an electrical connection relationship with the fingers 1011 at that position can be established. On the solar cell having such a structural configuration, due to the design of the first gaps 102b, the consumption of the paste for printing the fingers 1011 can be further reduced, and the cost of the paste for the fingers 1011 can be saved. In some embodiments, as shown in FIG. 7, to prevent that providing the first gap 102b and then printing the connecting portion 104 at the position of the first gap 102b may fail to effectively and electrically couple segments of the finger 1011 at the first gap 102b, in the embodiments of the present application, the finger 1011 at the position of the connecting portion 104 may alternatively be designed as a continuously integral structure, that is, the grid line at that position is not separated and disconnected by the first gap 102b, and the connecting portion 104 is directly printed and covers above the continuous grid line. In this case, the electrical contact area between the connecting portion 104 and the finger 1011 is larger, which is more conducive to the transmission of current from the finger 1011 to the connecting portion 104. The continuously integral structure of the finger 1011 in the embodiments of the present application refers to a design structure opposite to that having the first gap 102b, indicating that the grid line of the finger 1011 at the position originally having the first gap 102b remains continuously integral, rather than that a complete finger 1011 is continuously integral along the X direction as shown in the figure. In some embodiments, when the interconnect ribbon 103 is laid over the connecting portion 104, the interconnect ribbon 103 may be soldered to the connecting portion 104 without using materials such as solder paste, and the interconnect ribbon 103 is in direct contact with and electrically connected to the connecting portion 104. The interconnect ribbon 103 includes a core material and a solder layer covering a surface of the core material. For example, when a tin-plated copper ribbon is used as the interconnect ribbon 103, the tin-plated layer on the surface of the interconnect ribbon 103 may be melted, so that the interconnect ribbon 103 is soldered and fixed to the connecting portion 104. In the photovoltaic module according to the embodiments of the present application, the consumption of soldering materials such as solder paste can be reduced, and the process cost of string soldering can be lowered. The fixing between the interconnect ribbon 103 and the connecting portion 104 does not rely on other soldering materials. Of course, residual components from pretreatment such as surface cleaners are not considered as soldering materials between the interconnect ribbon 103 and the connecting portion 104. In this case, the interconnect ribbon 103 is in direct contact with the connecting portion 104 and the solar cell 10 at the position of the second gap 102a, which can simultaneously save insulating adhesive and soldering materials, reduce the height of the interconnect ribbon 103 relative to the solar cell 10, and enhance the bonding strength between the interconnect ribbon 103 and the solar cell 10. It can be seen from the above two embodiments that the finger 1011 at the position of the connecting portion 104 may be continuous or disconnected, and may be selected according to different functional requirements. In some embodiments, when the interconnect ribbon 103 is laid along the extending direction of the second side 10b (i.e., the Y direction as shown in the figure), the interconnect ribbon 103 has a first bottom portion at a position corresponding to the connecting portion 104, a second bottom portion at a position corresponding to the second gap 102a, and a third bottom portion at a position corresponding to a portion other than the connecting portion 104 and the second gap 102a. The bottom portion of the interconnect ribbon 103 refers to a portion of the interconnect ribbon 103 adjacent to the solar cell 10 along the thickness direction of the solar cell 10. In the same interconnect ribbon 103, along the thickness direction of the solar cell 10, a height difference between any two of the first bottom portion, the second bottom portion, and the third bottom portion is less than or equal to 0.5 mm. Exemplarily, the height difference between any two bottom portions may be 0.1 mm, 0.15 mm, 0.2 mm, 0.25 mm, 0.3 mm, 0.35 mm, 0.4 mm, 0.45 mm, or 0.5 mm. Accordingly, when the interconnect ribbon 103 is laid along the Y direction as shown in the figure, various portions of the interconnect ribbon 103 can be kept in the same horizontal plane as much as possible, preventing the interconnect ribbon 103 from forming significant bending deformation in the thickness direction of the solar cell 10, and improving the problem of poor soldering caused thereby. In some embodiments, the above height difference is less than or equal to 50 pm, which can enable the photovoltaic module to have higher quality. Exemplarily, the height difference between any two bottom portions may be 10 pm, 15 pm, 20 pm, 25 pm, 30 pm, 35 pm, 40 pm, 45 pm, or 50 pm. Further, a height difference between bottom portions of adjacent interconnect ribbons 103 is less than or equal to 90 pm. This can make the soldering heights and soldering performance differences among the plurality of interconnect ribbons 103 relatively small under the same process step and the same process conditions. Exemplarily, the height difference between bottom portions of adjacent interconnect ribbons 103 may be 10 pm, 20 pm, 30 pm, 40 pm, 50 pm, 60 pm, 70 pm, 80 pm, or 90 pm. In some embodiments, as shown in FIG. 8, in the same interconnect ribbon 103, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the interconnect ribbon 103 has a first width W1 at a position corresponding to the connecting portion 104, and a second width W2 at a position corresponding to the second gap 102a, and the first width W1 is greater than the second width W2. With such a design, the portion of the interconnect ribbon 103 having a larger width has a larger contact area with the connecting portion 104, resulting in better connection strength. In some embodiments, the first width W1 is at least 1.3 times the second width W2. The first width and the second width herein include the solder layer of the interconnect ribbon 103. Further, a first width at an edge region of the solar cell 10 is greater than a first width at a middle region of the solar cell 10. In some embodiments, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the first gap 102b has a first length, and the second gap 102a has a second length, with the second length being greater than the first length. Such a differentiated size design helps to ensure that the interconnect ribbon 103 maintains a sufficient gap from the grid lines on two sides of the second gap 102a, and that the distance among the electrically connected interconnect ribbon 103, connecting portion 104, and finger 1011 is relatively small, resulting in less electrical loss. For example, on the solar cell 10, each second length may be greater than the first length, or the second length at an end region of the solar cell may be greater than the first length, while the second length in the remaining regions is substantially equal to the first length. In some embodiments, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the second gap 102a has a second length. When the interconnect ribbon 103 used in the embodiments of the present application is a round wire interconnect ribbon having a circular cross section, the second length is at least 2 times a diameter of the round wire interconnect ribbon. When the interconnect ribbon 103 used in the embodiments of the present application is a flat wire interconnect ribbon having a rectangular cross section, the second length is at least 1.5 times a width of the flat wire interconnect ribbon. Compared with the flat wire interconnect ribbon, the round wire interconnect ribbon generally has a smaller diameter and a smaller contact area with the solar cell 10, and is prone to rolling and deviation. Therefore, when the round wire interconnect ribbon is used, a relatively large gap can be designed between the round wire interconnect ribbon and the fingers 1011 at the second gap 102a. The flat wire interconnect ribbon generally has a relatively larger contact area with the solar cell 10, and the rectangular interconnect ribbon 103 is relatively less prone to deviation and not easy to roll. A relatively small gap can be designed between the flat wire interconnect ribbon and the adjacent fingers 1011 of the opposite polarity, which can enhance the current collection effect of the fingers 1011. In this case, on two sides of the interconnect ribbon 103, dot-shaped or block-shaped insulating adhesive may be provided at end portions of the fingers 1011 of the opposite polarity, or no insulating adhesive may be provided. In some embodiments, at the second gap 102a, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), distances between the interconnect ribbon 103 and end portions of the fingers 1011 on two sides thereof may be the same or different, and a sum of the distances on the two sides is in a range of 200 pm to 600 pm. For example, the sum may be 200 pm, 300 pm, 400 pm, 500 pm, or 600 pm. Here, the "fingers on two sides" may refer to the fingers 1011 on two sides of the interconnect ribbon 103 that have a polarity opposite to that of the interconnect ribbon 103 or need to be insulated therefrom. When the specific shape of the interconnect ribbon 103 is uncertain, a certain safety distance may be reserved between the interconnect ribbon 103 and the fingers 1011 to ensure insulation effect. In some embodiments, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the second gap 102a has a second length. Along the extending direction of the second side 10b (i.e., the Y direction as shown in the figure), the second length of the second gap 102a adjacent to an edge of the solar cell 10 is greater than the second length of the second gap 102a located in a middle portion of the solar cell 10. The deviation at the head and tail ends of the interconnect ribbon 103 is often greater than that at a middle portion thereof. The second gap 102a adjacent to the edge of the solar cell 10 corresponds to a cut end portion of the interconnect ribbon 103. Designing the second length of the second gap 102a at this portion to be greater than the second length of the second gap 102a in the middle region of the solar cell 10 can improve the tolerance during laying of the end portion of the interconnect ribbon 103, and is less likely to cause short circuits at the end portion of the interconnect ribbon 103. In some embodiments, as shown in FIG. 4, an insulating adhesive 1015 is provided at end portions of the finger 1011 forming the second gap 102a, and a distance between two insulating adhesive portions 1015 corresponding to the second gap 102a may be at least 1.8 mm and at most 5 mm. For example, the distance may be 1.8 mm, 1.9 mm, 2 mm, 3 mm, 4 mm, or 5 mm. The distance between the two insulating adhesive portions 1015 may be the shortest gap between edges of the two insulating adhesive portions 1015. When the gap is 1.8 mm, the distance is relatively small, and the second width corresponding to the second gap 102a is also relatively narrow, that is, the end portions of the fingers 1011 on two sides of the second gap 102a are closer to each other, which facilitates current collection by the fingers 1011. When the gap is 5 mm, the distance is relatively large, and the second width corresponding to the second gap 102a is also relatively wide, that is, the end portions of the fingers 1011 on two sides of the second gap 102a are farther apart, and there is sufficient space between the two insulating adhesive portions 1015 for placing the interconnect ribbon 103, so that the interconnect ribbon 103 can be completely in direct contact with the solar cell 10. In some embodiments, the paste used for printing the fingers 1011 may be a fire-through paste, and the paste used for printing the connecting portions 104 may be a non-fire-through paste. The connecting portion 104 cannot pass through the passivation layer on the surface of the solar cell 10. Therefore, at the position of the first gap 102b, an end portion of the finger 1011 overlaps and is electrically connected to the connecting portion 104, and the end portion of the finger 1011 is at least partially located on a side of the connecting portion 104 facing away from the solar cell 10. That is, the end portion of the finger 1011 overlaps on an upper layer of the connecting portion 104. On one hand, this can ensure sufficient contact between the finger 1011 and the connecting portion 104 to improve electrical connection performance; on the other hand, the protruding end portions of the finger 1011 on two sides can serve to limit the position of the interconnect ribbon 103. In some embodiments, at the position of the connecting portion 104, the finger 1011 may press on a surface of the connecting portion 104 and protrude from the surface of the connecting portion 104, or the connecting portion 104 may cover the finger 1011, with a portion of the connecting portion 104 being lifted up by the finger 1011. In some embodiments, as shown in FIG. 3, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the interconnect ribbons 103 include a middle interconnect ribbon 103, an edge interconnect ribbon 1031 at the left edge, and an edge interconnect ribbon 1032 at the right edge. At a position where any one of the edge interconnect ribbons passes, the fingers 1011 having a polarity opposite to that of the edge interconnect ribbon are of a continuously integral structure, and an insulating adhesive 1015 is provided between the edge interconnect ribbon and the fingers 1011 of the opposite polarity. Taking the edge interconnect ribbon 1032 at the right edge as an example with reference to FIG. 3, the edge interconnect ribbon 1032 at the right edge is laid along the Y direction as shown in the figure, and electrically connects the positive fingers 1011a through corresponding connecting portions 104. The negative fingers 1011b between two adjacent positive fingers 1011a are of a continuously integral structure at the position where the edge interconnect ribbon 1032 passes. To prevent short circuits between these negative fingers 1011b and the edge interconnect ribbon 1032, an insulating adhesive 1015 is provided below the edge interconnect ribbon 1032 on the continuously integral negative fingers 1011b. The solar cell 10 may adopt the design shown in FIG. 3 as a whole, or may locally adopt the design shown in FIG. 3. In some embodiments, when the edge interconnect ribbon is connected to the connecting portions 104, a conductive layer may be formed by applying solder paste or the like on an upper layer of some of the connecting portions 104. Through the fusing action of the conductive layer, the edge interconnect ribbon can be more reliably fixed and connected to the connecting portions 104. In some embodiments, as shown in FIG. 3, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), the interconnect ribbons 103 include a middle interconnect ribbon 103, an edge interconnect ribbon 1031 at the left edge, and an edge interconnect ribbon 1032 at the right edge. As shown in FIG. 9, the electrode structure 101 further includes an edge busbar 1014 adjacent to an edge of the solar cell 10. The edge busbar 1014 is closer to the edge of the solar cell 10 than the edge interconnect ribbon. As shown in FIG. 9, that is, the edge busbar 1014 is closer to an outer side of the solar cell 10 than the edge interconnect ribbon. As shown in FIG. 9, among the fingers 1011 connected to the edge busbar 1014, some of the fingers 1011 are continuously-integral fingers, and these continuously-integral fingers 1011 electrically connect the edge busbar 1014 to the connecting portions 104 of the same polarity located on an inner side of the edge busbar 1014. The current collected by the edge busbar 1014 can be transmitted leftward through the continuously-integral fingers 1011 to another adjacent interconnect ribbon 103 from right to left. Meanwhile, the edge interconnect ribbon 1031 at the left edge and the edge interconnect ribbon 1032 at the right edge are each arranged along the extending direction of the second side 10b (i.e., the Y direction as shown in the figure). Taking an edge interconnect ribbon laid on the left side of the edge busbar 1014 as an example, the edge interconnect ribbon at this position is electrically connected to the positive fingers 1011a, and the negative fingers 1011b are electrically connected to the edge busbar 1014. In this case, the continuously integral grid line structure may be designed on some of the negative fingers 1011b. To prevent short circuits when the edge interconnect ribbon passes through the negative fingers 1011b at the continuously integral portions thereof, an insulating adhesive 1015 is provided between the continuously integral negative fingers 1011b and the edge interconnect ribbon. In FIG. 9, arrows beside the fingers 1011 illustrate the path of current transmitted from the end portion adjacent to the second side 10b through the edge busbar 1014 and the continuously-integral fingers 1011. As shown in FIG. 9, the edge busbar 1014 may be electrically connected to a plurality of continuously-integral fingers 1011, and a plurality of parallel current transmission paths may be formed at different positions of the solar cell adjacent to the second side 10b. The direction of the current transmission paths is generally along the X direction. Current is transmitted between the edge interconnect ribbon 1032 at the right edge and another interconnect ribbon 103 adjacent to the edge interconnect ribbon 1032, with the current transmission direction flowing from the edge interconnect ribbon 1032 to the other interconnect ribbon 103 adjacent to the edge interconnect ribbon 1032. The current transmission paths may include one, two, or more than two paths, and each current transmission path is independent of one another, so that currents in different regions at the edge of the solar cell can be comprehensively and completely collected, reducing power loss. In this case, at the edge interconnect ribbon, some of the fingers 1011 are disconnected, and some of the fingers 1011 are continuously integral. This can further reduce the material loss of the insulating adhesive and the conductive layer in the edge region. Further, the fewer the continuously-integral fingers 1011 used for current transmission of the edge busbar 1014, the more insulating adhesive and conductive layer material are saved. In some embodiments, one or two continuously-integral fingers 1011 are provided at two ends of the edge busbar 1014. In some embodiments, as shown in FIG. 10, an insulating adhesive 1015 is provided between the continuously-integral fingers 1011 and the edge interconnect ribbon. When the edge interconnect ribbon extends along the Y direction as shown in the figure and is electrically connected to at least one finger 1011 adjacent to the continuously-integral fingers 1011, poor contact is more likely to occur due to a height difference. Therefore, in the embodiments of the present application, the electrode structure 101 further includes a first connecting portion 1016. The function of the first connecting portion 1016 is similar to that of a busbar in a conventional solar cell. At least one finger 1011 adjacent to the continuously-integral fingers 1011 is electrically connected to an adjacent connecting portion 104 through the first connecting portion 1016, forming a first unipolar unit 105. The provision of the first connecting portion 1016 can ensure that, in the case where the soldering reliability between the fingers 1011 adjacent to the continuously-integral fingers 1011 and the interconnect ribbon 103 is poor, the current can be transmitted through the first connecting portion 1016 to the adjacent connecting portion 104, and then electrically coupled to the corresponding edge interconnect ribbon. Further, when the edge interconnect ribbon is electrically connected to at least one finger 1011 adjacent to the continuously-integral fingers 1011, the other fingers 1011 adjacent to the continuously-integral fingers 1011 may be of a continuously integral structure without the connecting portions 104, or may be provided with the connecting portions 104, and the connecting portions 104 may be in direct contact with the edge interconnect ribbon without a conductive layer. For example, taking FIG. 10 as an example, the continuously-integral fingers 1011 may be the negative fingers 1011b as shown in FIG. 10, and the fingers 1011 adjacent thereto may be the positive fingers 1011a as shown in FIG. 10. When the positive fingers 1011a are of a continuously integral structure, they may be provided without the connecting portions 104, or may be provided with the connecting portions 104. When the connecting portions 104 are provided, the edge interconnect ribbon is in direct contact with the connecting portions 104 on the positive fingers 1011a without a conductive layer. As shown in FIG. 10, when the first connecting portion 1016 is relatively long, it can connect a plurality of fingers 1011. At two ends of the first connecting portion 1016 in a length direction, one continuously integral negative finger 1011b is provided at each end, and a plurality of positive fingers 1011a are distributed between the two continuously integral negative fingers 1011b. The first connecting portion 1016 can connect these positive fingers 1011a together to form the first unipolar unit 105. When the continuously-integral fingers 1011 are the positive fingers 1011a, the fingers of the opposite polarity may be the negative fingers 1011b, and vice versa. In this case, the first connecting portion 1016 connects a plurality of fingers of the opposite polarity together to form the first unipolar unit 105. The first unipolar unit 105 may be entirely of positive electrodes or entirely of negative electrodes, collecting current through the plurality of fingers 1011 extending in the X direction, and then the current can be collected to the interconnect ribbon at that position through the first connecting portion 1016. Accordingly, the risk of damage to the fingers 1011 caused by directly soldering the interconnect ribbon to the fingers 1011 can be avoided. At the same time, the first connecting portion 1016 and the interconnect ribbon can form a redundant backup protection structure with each other, avoiding local failure of current collection by the interconnect ribbon when the interconnect ribbon is used alone for connection, which helps to improve the working stability and reliability of the solar cell. In some embodiments, as shown in FIG. 10, among the fingers 1011 electrically connected to the edge interconnect ribbon, at least one connecting portion 104 is provided, and the edge interconnect ribbon is electrically connected to the fingers 1011 via the connecting portion 104. As shown in FIG. 10, in the aforementioned first unipolar unit 105, at least one connecting portion 104 is provided to maintain electrical coupling of the corresponding fingers 1011, and to achieve reliable connection between the corresponding fingers 1011 and the edge interconnect ribbon. As shown in FIG. 11, the embodiments of the present application further illustrate a schematic diagram in which three connecting portions 104 are provided in the first unipolar unit 105. With the increase in the number of the connecting portions 104, it is more conducive to improving the connection reliability between the edge interconnect ribbon and the corresponding fingers 1011 in the first unipolar unit 105. In addition, to more intuitively illustrate a solar cell used in the embodiments of the present application, FIG. 12 further shows a schematic diagram of a complete layout of the electrode structure 101 on the surface of the solar cell according to the embodiments of the present application. FIG. 13 is a partial enlarged schematic view of position I in FIG. 12. It can be seen that FIG. 13 at least illustrates the second side 10b, the second gaps 102a, the connecting portions 104, the positive fingers 1011a, the negative fingers 1011b, the first connecting portion 1016, and the second connecting portion 1017 in the embodiments of the present application, as well as the positions and connection relationships of these structures as described in the foregoing embodiments. In some embodiments, for any one of the edge interconnect ribbon 1031 at the left edge and the edge interconnect ribbon 1032 at the right edge, when it is connected to the connecting portions 104, the interconnect ribbon 103 may be soldered to the connecting portions 104 without using materials such as solder paste, so that the interconnect ribbon 103 is in direct contact with and electrically connected to the connecting portions 104. In this case, the conductive layer material in the edge region can be further saved. Further, at end portions of the fingers 1011 of opposite polarity on two sides of the edge interconnect ribbon, dot-shaped or block-shaped insulating adhesive may be provided, or no insulating adhesive may be provided at all, and the edge interconnect ribbon is insulated from the end portions of the fingers 1011 through gaps. In some embodiments, along the extending direction of the first side 10a (i.e., the X direction as shown in the figure), a distance between a group of edge interconnect ribbons adjacent to a same side of the solar cell and the edge busbar 1014 is in a range of 2 mm to 6 mm. For example, as shown in FIGS. 3 and 9, the distance between the edge interconnect ribbon 1032 at the right edge and the edge busbar 1014 may be 2 mm, 2.5 mm, 3 mm, 3.5 mm, 4 mm, 4.5 mm, 5 mm, 5.5 mm, or 6 mm. When the distance is too small, it is not conducive to the laying and arrangement of the edge interconnect ribbon 1032 at the right edge, and it is easy to contact and abut against the edge busbar 1014. When the distance is too large, it is easy to affect the overall arrangement density of the interconnect ribbons 103 in the cell string. Therefore, the specific value of the above distance can be determined according to the specification and size of the solar cell and the arrangement density of the interconnect ribbons 103 in the cell string. In some embodiments, as shown in FIG. 9, among the fingers 1011 insulated from the edge interconnect ribbon, some of the fingers 1011 are provided with the second gaps 102a, and others of the fingers 1011 are continuously-integral fingers. Taking FIG. 3 and FIG. 9 as an example, the edge interconnect ribbon 1032 at the right edge is insulated from the negative fingers 1011b. Specifically, when achieving insulation, two different ways may be adopted according to the positions of the negative fingers 1011b. Some of these negative fingers 1011b are provided with the second gaps 102a, and maintain insulation from the edge interconnect ribbon 1032 at the right edge through the second gaps 102a. Others of the negative fingers 1011b are of a continuously integral structure. In this case, an insulating adhesive 1015 may be applied at intersections of the continuously integral negative fingers 1011b and the interconnect ribbon 103. In some embodiments, the insulating adhesive 1015 is provided only on the continuously-integral fingers 1011, that is, on the fingers 1011 that generate current for the edge busbar 1014, so that the continuously-integral fingers 1011 are not interrupted. For example, in FIG. 9, the continuously-integral fingers 1011 are negative fingers 1011b. In other embodiments, the continuously-integral fingers 1011 may also be positive fingers 1011a. In some embodiments, among the fingers 1011 insulated from the edge interconnect ribbon, the more the continuously-integral fingers 1011, the more insulating adhesive is correspondingly consumed; the fewer the continuously-integral fingers 1011, the less conducive it is to collecting current. Therefore, in the embodiments of the present application, the number of the continuously-integral fingers 1011 may be 1 to 10. For example, the number of the continuously-integral fingers 1011 may be 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In some embodiments, the number of the continuously-integral fingers 1011 may be 1 to 3. The number of the continuously-integral fingers 1011 here refers to the number of the continuously-integral fingers 1011 among the fingers 1011 insulated from the edge interconnect ribbon in an edge region of the solar cell adjacent to one second side 10b, that is, the number of the continuously-integral fingers 1011 connected to one edge busbar 1014. In some embodiments, as shown in FIG. 3 and FIG. 9, among the fingers 1011 insulated from the edge interconnect ribbon, the continuously-integral fingers 1011 are connected to another interconnect ribbon. Therefore, a width of the continuously-integral fingers 1011 is greater than widths of the remaining fingers 1011, which can ensure that the continuously-integral fingers 1011 have stronger overcurrent performance and can reduce the risk of finger ablation and disconnection when transmitting large currents. In some embodiments, for the aforementioned continuously-integral fingers 1011 having a larger width, they may be composed of two layers of finger lines: one layer is a bottom-layer finger line printed and disposed on the surface of the solar cell 10, and the other layer is a toplayer finger line printed and disposed on a side of the bottom-layer finger line facing away from the solar cell 10, that is, the top-layer finger line is laminated and printed to cover above the bottom-layer finger line. A width of the top-layer finger line is greater than a width of the bottom-layer finger line or widths of the remaining fingers, so that the continuously-integral fingers 1011 can have a larger width. Moreover, when printing the bottom-layer finger line and the top-layer finger line respectively, the pastes used may be the same or different. For example, when printing the bottom-layer finger line of a conventional width, the paste for the fingers may be used, and the printing is performed at the same width and simultaneously with the fingers 1011. Then, when printing the wider top-layer finger line, the paste for the connecting portions 104 may be used instead, and the printing is performed simultaneously with the connecting portions 104. In some embodiments, as shown in FIG. 10, the electrode structure 101 in the embodiments of the present application further includes a second connecting portion 1017. The second connecting portion 1017 may be connected to the interconnect ribbon 103 in the middle of the solar cell, and the second connecting portion 1017 may be located between two adjacent middle interconnect ribbons 103. The function of the second connecting portion 1017 is similar to that of a busbar in a conventional solar cell. The second connecting portion 1017 extends along the Y direction and can electrically connect a plurality of fingers of the same polarity together to form a plurality of second unipolar units. Taking the configuration shown in FIG. 10 as an example, the second connecting portion 1017 is arranged along the extending direction of the second side 10b, and the second connecting portion 1017 electrically connects the continuously-integral fingers 1011 with the connecting portions 104 of the same polarity, forming a second unipolar unit. The continuously-integral fingers 1011 are derived from the fingers 1011 insulated from the edge interconnect ribbon, that is, derived from the fingers 1011 electrically connected to the edge busbar 1014. In other embodiments, the second connecting portion 1017 has a function similar to that of the first connecting portion 1016, and the second unipolar unit and the first unipolar unit 105 may be the same. In the present application, the second connecting portion 1017 can avoid the risk of damage to the fingers 1011 caused by directly soldering the interconnect ribbon to the fingers 1011. At the same time, the second connecting portion 1017 and the interconnect ribbon can form a redundant backup protection structure with each other, avoiding local failure of the interconnect ribbon when the interconnect ribbon is used alone for connection, which helps to improve the working stability and reliability of the solar cell. In some embodiments, a gap region is provided between two adjacent fingers 1011 of opposite polarities. The gap region is commonly referred to as a "gap" region, that is, an isolation region between PN regions on the cell. Along a thickness direction of the solar cell 10, an insulating adhesive 1015 is provided between the edge interconnect ribbon and the continuously-integral fingers 1011, and the insulating adhesive 1015 at least partially covers the aforementioned gap region. In such a configuration, when the same amount of the insulating adhesive 1015 is used, the area covered by the insulating adhesive 1015 is larger, and its thickness is reduced, which helps to reduce the height difference between the insulating adhesive 1015 and the connecting portions 104 on two sides thereof, and can improve the soldering effect between the interconnect ribbon 103 and the connecting portions 104 on two sides of the insulating adhesive 1015. In some embodiments, referring to FIG. 14 and FIG. 15, the electrode structure 101 further includes a plurality of end busbars 1012. Along the extending direction of the second side 10b, the end busbars 1012 of a preset length are provided adjacent to the first side 10a of the solar cell, and the end busbars 1012 are connected to at least two of the connecting portions 104. Specifically, as shown in FIG. 14 and FIG. 15, to ensure accurate and reliable electrical connection between adjacent solar cells during string soldering, in the solar cell according to the embodiments of the present application, the electrode structure 101 further includes a plurality of end busbars 1012. The end busbars 1012 may at least mean: grid lines located adjacent to the first side 10a of the solar cell, extending from the first side 10a inward along the Y direction, and connected to some of the fingers 1011. The end busbars 1012 may be relatively short in length, but are slightly thicker compared to the fingers 1011. As shown in FIG. 14, along the extending direction Y of the second side 10b, the end busbars 1012 are provided adjacent to both sides of the solar cell (i.e., the upper and lower first sides 10a). The end busbar 1012 at the upper side in FIG. 14 may extend downward through the connecting portions 104 on a plurality of fingers 1011 of the same polarity. For example, when the end busbar 1012 is relatively short, it may be connected to two connecting portions 104. When the end busbar 1012 is relatively long, it may be connected to more than two connecting portions 104. Therefore, by providing the end busbars 1012 adjacent to the first side 10a of the solar cell, accurate and reliable soldering between the interconnect ribbon and the solar cell can be ensured, and local failure of current collection by the interconnect ribbon when the interconnect ribbon is used alone for connection can be avoided, which helps to improve the working stability and reliability of the solar cell. In addition, the end busbars 1012 can be soldered to two or more small-sized connecting portions 104. Compared with the connecting portion structure having a larger area in conventional solar cells, the paste for the connecting portions can also be appropriately saved, and the cost of the electrode structure is lower. As shown in FIG. 13, along the extending direction Y of the second side 10b, an end busbar 1012 is provided at an end adjacent to the first side 10a of the solar cell. During string soldering, one end of the interconnect ribbon for connecting two solar cells (for example, a first solar cell and a second solar cell) in series is connected to the end busbar 1012 on the first solar cell, then extends along the Y direction through the solar cell 10 and the other end of the first solar cell, then crosses the inter-cell gap between the first solar cell and the second solar cell, until extending to the position of the end busbar 1012 of the second solar cell. Therefore, based on FIG. 14, when the interconnect ribbon passes through the inter-cell gap between the first solar cell and the second solar cell, it is not cut off, and the risk of deviation in the arrangement and soldering of the interconnect ribbon is relatively small. Moreover, the end busbar 1012 adjacent to the inter-cell gap can be omitted, which can further save the electrode paste for the end busbars 1012, and further reduce the paste cost. In some embodiments, referring to FIG. 14, the electrode structure 101 includes a plurality of middle busbars 1013. Along the extending direction Y of the second side 10b, the middle busbars 1013 are electrically connected to a plurality of the connecting portions 104. Specifically, in the present application, the middle busbars 1013 at least mean: grid lines between the edge interconnect ribbons 1031, 1032 and connected to at least two connecting portions 104. Correspondingly, when preparing the solar cell according to the embodiments of the present application, the fingers 1011, the second gaps 102b, the middle busbars 1013, and the connecting portions 104 may be formed by screen printing. The width of the middle busbars 1013 may be slightly thicker than the fingers 1011, but thinner than conventional busbars. By pre-printing the middle busbars 1013 and electrically connecting them to the connecting portions 104 of the fingers 1011 of the same polarity, local failure of current collection by the interconnect ribbon when the interconnect ribbon is used alone for connection can be avoided, which helps to improve the working stability and reliability of the solar cell. It can also avoid the defect of finger 1011 fusing caused by the small size of the connecting portions 104 in a completely busbar-free solution, and can appropriately improve the yield of string soldering. Of course, in some embodiments, along the extending direction Y of the second side 10b, the solar cell may include at least two connecting portions 104 not connected to grid lines. Specifically, when preparing the solar cell according to the embodiments of the present application, the fingers 1011, the second gaps 102a, and the connecting portions 104 may be formed by screen printing. During string soldering, the interconnect ribbon is connected to the fingers 1011 of the same polarity via the connecting portions 104. The solar cell may include at least two connecting portions 104 not connected to grid lines, that is, the above-mentioned end busbars and / or middle busbars may not be required. In this way, the interconnect ribbon can be used to replace the busbars to collect current from the fingers 1011 and collect and output the current. Accordingly, such a solar cell is a solar cell with reduced busbars or no busbars, which can reduce the cost of busbar paste. In some embodiments, referring to FIG. 14 to FIG. 16, the electrode structure 101 further includes busbars, and the busbars include end busbars 1012 and / or middle busbars 1013. An insulating adhesive 1015 is provided at intersections of the fingers 1011 with the interconnect ribbons or the busbars of the opposite polarity. Specifically, as shown in FIG. 14 and FIG. 15, the busbars include the end busbars 1012. The polarity of the fingers 1011 connected to the end busbars 1012 or the interconnect ribbons is opposite to that of the other fingers 1011. Therefore, to avoid short circuits caused by contact and electrical coupling at intersections of the interconnect ribbons 103 or the end busbars 1012 with the fingers 1011 when laying the interconnect ribbons 103 or the end busbars 1012, an insulating adhesive 1015 is provided at intersections of the fingers 1011 of the solar cell with the interconnect ribbons or the end busbars 1012 of the opposite polarity. Referring to FIG. 16, the busbars include the middle busbars 1013. The continuously integral portions of the fingers 1011 may be integrally formed with other portions of the fingers 1011 by one-time printing using the same paste. The polarity of the fingers 1011 connected to the interconnect ribbon via the connecting portions 104 is opposite to that of the continuously-integral fingers 1011. Therefore, to avoid short circuits caused by contact and electrical coupling at intersections of the interconnect ribbon with the continuously-integral fingers 1011 when laying the interconnect ribbon, as shown in FIG. 16, when the middle busbar 1013 passes through the continuously-integral fingers 1011, an insulating adhesive 1015 is provided at the intersections thereof. In some embodiments, referring to FIG. 17 to FIG. 19, the solar cell according to the embodiments of the present application is a back-contact solar cell; and / or, along the extending direction of the first side 10a, a maximum dimension of the connecting portion 104 is a, and a is not less than a width of the first gap 102b; along the extending direction of the second side 10b, a maximum dimension of the connecting portion 104 is b, and b is smaller than a distance between two adjacent fingers 1011 of the same polarity. Specifically, in the embodiments of the present application, the solar cell is a back-contact solar cell. Meanwhile, for connecting portions 104 of various shapes, the maximum dimension of the connecting portion 104 along the X direction is a, and the maximum dimension of the connecting portion 104 along the Y direction is b. a and b respectively satisfy the following conditions: a is not less than the width of the first gap 102b, so that the two segments of the fingers 1011 of the same polarity on two sides of the first gap 102b can be reliably connected together. Along the Y direction as shown in the figure, b is smaller than the distance between two adjacent fingers 1011 of the same polarity, so that short circuit between the finger 1011 connected to the connecting portion 104 and another finger 1011 of opposite polarity adjacent in the Y direction can be avoided. Exemplarily, 0.5 mm < a < 6 mm, and 0.05 mm < b < 1 mm. In some embodiments, the connecting portion 104 may be symmetric with respect to the extending direction of the fingers 1011 (which may be the X direction). For example, when the connecting portion 104 is a rectangle as shown in FIG. 17, along the X direction, the maximum dimension a of the connecting portion 104 is the length of the rectangle, and along the Y direction, the maximum dimension b of the connecting portion 104 is the width of the rectangle, with 0.5 mm < a < 6 mm and 0.05 mm < b < 1 mm. When the connecting portion 104 is a diamond-like shape as shown in FIG. 18, along the X direction, the maximum dimension a of the connecting portion 104 is a distance between two short sides of the diamond-like shape, with 0.5 mm < a < 6 mm. Along the Y direction, the maximum dimension b of the connecting portion 104 is a distance from a highest point to a lowest point of the diamond-like shape, and a middle width of the diamond is b, with 0.05 mm < b < 1 mm. In some embodiments, 0.1 mm < b < 0.5 mm. When the connecting portion 104 is a combined shape of a rectangle and a trapezoid as shown in FIG. 19, it also satisfies: 0.5 mm < a < 6 mm, and 0.05 mm < b < 1 mm. In some embodiments, 0.1 mm < b < 0.5 mm. The shape and size of the connecting portion 104 according to the embodiments of the present application can provide a larger soldering contact area compared to the width of the finger 1011, while the soldering contact area is relatively small compared to conventional connecting portions (pads). This can avoid the problem of low open-circuit voltage caused by a large composite area between a large connecting portion and the silicon substrate of the solar cell, and can reduce current transmission power consumption. Herein, the terms "comprise", "include", or any other variants thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or device that includes a series of elements includes not only those elements but also other elements not expressly listed, or also includes elements inherent to such process, method, article, or device. Without further limitation, an element defined by the phrase "including a ..." does not exclude the presence of additional identical elements in the process, method, article, or device that includes the element. In addition, the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in a reverse order depending on the functions involved. For example, the described methods may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described in some examples may be combined in other examples. Reference herein to "one embodiment," "an embodiment," or "one or more embodiments" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. In addition, the examples of the phrase "in one embodiment" herein do not necessarily all refer to the same embodiment. In the description provided herein, numerous specific details are set forth. However, the embodiments of the present application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques are not described in detail so as not to obscure the understanding of this description. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "including" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The use of words such as first, second, and third does not imply any order. These words may be construed as names. Finally, the above embodiments are only used to describe the technical solutions of the 5 present application, and are not intended to limit the same. Although the present application has been described in detail with reference to the foregoing embodiments, a person of ordinary skill in the art should understand that the technical solutions described in the foregoing embodiments may still be modified, or some of the technical features thereof may be equivalently replaced. Such modifications or replacements do not cause the essence of the corresponding technical 10 solutions to depart from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A photovoltaic module, comprising:a plurality of solar cells, the solar cells comprising a first side and a second side; the solar cell being provided with an electrode structure, the electrode structure comprising a plurality of fingers, the fingers being at least partially parallel to the first side, and along an extending direction of the second side, fingers of opposite polarities being alternately arranged;along an extending direction of the first side, the finger comprising a plurality of second gaps and a plurality of connecting portions; the plurality of second gaps dividing the finger into a plurality of segments, wherein the second gape is an interrupted structure; along the extending direction of the first side and the extending direction of the second side, the second gaps and the connecting portions being adjacently arranged; anda plurality of interconnect ribbons, the interconnect ribbons being arranged along the extending direction of the second side to connect adjacent solar cells in series; any one of the interconnect ribbons being electrically connected to the connecting portions of the fingers of one polarity, and at positions corresponding to the second gaps of the fingers of the other polarity, the interconnect ribbon being at least partially in contact with a surface of the solar cell.

2. The photovoltaic module according to claim 1, wherein an insulating adhesive is provided at the second gap, and along the extending direction of the first side, the interconnect ribbon is in contact with the insulating adhesive.

3. The photovoltaic module according to claim 1, wherein an insulating adhesive is provided at the second gap, and along the extending direction of the first side, a gap exists between the interconnect ribbon and the insulating adhesive.

4. The photovoltaic module according to claim 1, wherein along the extending direction of the first side, the finger further comprises a plurality of first gaps, the connecting portions are provided at the plurality of first gaps, and the connecting portions electrically couple segments of the finger at the first gaps.

5. The photovoltaic module according to claim 1, wherein the finger is continuously integral at each of the connecting portions.

6. The photovoltaic module according to claim 1, wherein the interconnect ribbon is in direct contact with and electrically connected to each of the connecting portions.

7. The photovoltaic module according to claim 1, wherein the interconnect ribbon has a first bottom portion at a position corresponding to each of the connecting portion, a second bottom portion at a position corresponding to the second gap, and a third bottom portion at a position corresponding to a portion other than the connecting portion and the second gap; andin the same interconnect ribbon, along a thickness direction of the solar cell, a height difference between any two of the first bottom portion, the second bottom portion, and the third bottom portion is less than or equal to 0.5 mm.

8. The photovoltaic module according to claim 7, wherein in the same interconnect ribbon, along the thickness direction of the solar cell, the height difference between any two of the first bottom portion, the second bottom portion, and the third bottom portion is less than or equal to 50 gm.

9. The photovoltaic module according to claim 1, wherein in the same interconnect ribbon, along the extending direction of the first side, the interconnect ribbon has a first width at a position corresponding to each of the connecting portions and a second width at a position corresponding to the second gap, the first width being at least 1.3 times the second width.

10. The photovoltaic module according to claim 4, wherein along the extending direction of the first side, each of the first gaps has a first length, and the second gap has a second length, the second length being greater than the first length.

11. The photovoltaic module according to claim 1, wherein along the extending direction of the first side, the second gap has a second length, the interconnect ribbon comprises a round wire interconnect ribbon having a circular cross section, and the second length is at least 2 times a diameter of the round wire interconnect ribbon; or the interconnect ribbon comprises a flat wire interconnect ribbon having a rectangular cross section, and the second length is at least 1.5 times a width of the flat wire interconnect ribbon.

12. The photovoltaic module according to claim 1, wherein at the second gap, along the extending direction of the first side, a sum of distances between the interconnect ribbon and end portions of the fingers on two sides thereof is in a range of 200 gm to 600 gm.

13. The photovoltaic module according to claim 1, wherein along the extending direction of the first side, the second gap has a second length; andalong the extending direction of the second side, the second length of the second gap adjacent to an edge of the solar cell is greater than the second length of the second gap located in a middle portion of the solar cell.

14. The photovoltaic module according to claim 1, wherein an insulating adhesive is provided at end portions of the finger forming the second gap, and a distance between two insulating adhesive portions corresponding to the second gap is in a range of 1.8 mm to 5 mm.

15. The photovoltaic module according to claim 4, wherein at each of the first gaps, an end portion of the finger overlaps and is electrically connected to each of the connecting portions, and the end portion of the finger is at least partially located on a side of the connecting portion facing away from the solar cell.

16. The photovoltaic module according to any one of claims 1 to 15, wherein along the extending direction of the first side, the interconnect ribbons comprise an edge interconnect ribbon adjacent to an edge of the solar cell; andat a position through which the edge interconnect ribbon passes, the finger having a polarity opposite to a polarity of the edge interconnect ribbon is continuously integral at each of the connecting portions, and an insulating adhesive is provided between the edge interconnect ribbon and the finger of the opposite polarity.

17. The photovoltaic module according to claim 16, wherein the edge interconnect ribbon is fixed to and electrically connected to at least some of the connecting portions through a conductive layer.

18. The photovoltaic module according to any one of claims 1 to 15, wherein along the extending direction of the first side, the interconnect ribbons comprise an edge interconnect ribbon adjacent to an edge of the solar cell, and the electrode structure further comprises an edge busbar adjacent to the edge of the solar cell; the edge busbar is closer to the edge of the solar cell than the edge interconnect ribbon;the edge interconnect ribbon is arranged along the extending direction of the second side, the edge interconnect ribbon is electrically connected to the fingers of one polarity, the fingers of the other polarity are electrically connected to the edge busbar, and the edge busbar is electrically connected, through the continuously-integral fingers, to the connecting portions of the same polarity located on an inner side of the edge busbar; and an insulating adhesive is provided between the edge interconnect ribbon and the continuously-integral fingers.

19. The photovoltaic module according to claim 18, wherein the electrode structure further comprises a first connecting portion, the first connecting portion being arranged along the extending direction of the second side;among the fingers electrically connected to the edge interconnect ribbon, at least one finger adjacent to the continuously-integral finger along the extending direction of the second side iselectrically connected to an adjacent connecting portion through the first connecting portion, to form a first unipolar unit.

20. The photovoltaic module according to claim 18, wherein among the fingers electrically connected to the edge interconnect ribbon, at least one of the connecting portions is provided, and the edge interconnect ribbon is electrically connected to the fingers via the connecting portion.

21. The photovoltaic module according to claim 20, wherein the edge interconnect ribbon is in direct contact with and electrically connected to the connecting portion.

22. The photovoltaic module according to claim 18, wherein along the extending direction of the first side, a distance between the edge interconnect ribbon and the edge busbar is in a range of 2 mm to 6 mm.

23. The photovoltaic module according to claim 18, wherein among the fingers insulated from the edge interconnect ribbon, some of the fingers are provided with the second gaps, and others of the fingers are the continuously-integral fingers.

24. The photovoltaic module according to claim 18, wherein among the fingers insulated from the edge interconnect ribbon, the number of the continuously-integral fingers is 1 to 10.

25. The photovoltaic module according to claim 18, wherein among the fingers insulated from the edge interconnect ribbon, the number of the continuously-integral fingers is 1 to 3.

26. The photovoltaic module according to claim 18, wherein a width of the continuously-integral finger is greater than widths of the remaining fingers.

27. The photovoltaic module according to claim 26, wherein the continuously-integral finger comprises a bottom-layer finger line and a top-layer finger line arranged in layers, the bottomlayer finger line being disposed on a surface of the solar cell, the top-layer finger line being disposed on a side of the bottom-layer finger line facing away from the solar cell, and a width of the top-layer finger line being greater than a width of the bottom-layer finger line or widths of the remaining fingers.

28. The photovoltaic module according to claim 18, wherein the electrode structure further comprises a second connecting portion, the second connecting portion being arranged along the extending direction of the second side; andthe second connecting portion electrically connects the continuously-integral fingers with the connecting portions of the same polarity, to form a second unipolar unit.

29. The photovoltaic module according to claim 18, wherein a gap region is provided between two adjacent fingers of opposite polarities; andalong a thickness direction of the solar cell, an insulating adhesive is provided between the edge interconnect ribbon and the continuously-integral fingers, and the insulating adhesive at least partially covers the gap region.

30. The photovoltaic module according to claim 1, wherein the electrode structure further comprises a plurality of end busbars; along the extending direction of the second side, the end busbars of a preset length are provided adjacent to the first side of the solar cell, and the end busbars are connected to at least two of the connecting portions; and / or the electrode structure further comprises a plurality of middle busbars; along the extending direction of the second side, the middle busbars are electrically connected to a plurality of the connecting portions.

31. The photovoltaic module according to claim 30, wherein the electrode structure comprises busbars, the busbars comprise the end busbars and / or the middle busbars, and an insulating adhesive is provided at intersections of the fingers with the interconnect ribbons or the busbars of the opposite polarity.

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