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

A photovoltaic module

[0001] Cross-reference to related applications

[0002] This application claims priority to Chinese Patent Application No. 202410676883.1, filed on May 28, 2024, entitled "A Solar Cell, a Photovoltaic Module and a Method for Preparing a Photovoltaic Module", the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of photovoltaic cells, and in particular to a photovoltaic module. Background Technology

[0004] In the photovoltaic cell industry, when using interconnect strips to string two adjacent cells together, in order to ensure reliable insulation between the interconnect strips and the sub-grids with opposite polarity, insulating adhesive (commonly known as green adhesive) is usually printed on the surface of the cell body. The insulating adhesive is used to insulate and isolate the interconnect strips from the sub-grids.

[0005] However, the current design of the electrode structure on the surface of the solar cell requires a large amount of insulating adhesive to achieve insulation between the interconnect strips and the sub-grid with opposite polarity, which increases the material cost of photovoltaic modules and also increases the manufacturing process time. Summary of the Invention

[0006] The purpose of this application is to provide a photovoltaic module that addresses the problem of excessive consumption of insulating adhesive in traditional photovoltaic modules.

[0007] To solve the above-mentioned technical problems, this application is implemented as follows:

[0008] A photovoltaic module, comprising:

[0009] Multiple battery bodies, each battery body including a first side and a second side; each battery body is provided with an electrode structure, the electrode structure including multiple sub-grids, each sub-grid being at least partially parallel to the first side and extending along the second side, with two types of sub-grids of opposite polarity alternately arranged;

[0010] Along the extending direction of the first side, the sub-gate includes a plurality of second notches and a plurality of connecting portions, the second notches and the connecting portions being arranged adjacent to each other, the plurality of second notches dividing the sub-gate into multiple segments, wherein the second notch portion is a gap-off structure; along the extending direction of the first side and the second side, the second notches and the connecting portions are arranged adjacent to each other;

[0011] Multiple interconnecting bars are arranged along the extension direction of the second side, connecting adjacent battery bodies in series; any one of the interconnecting bars is electrically connected to the connection portion of the sub-gate of one polarity, and at least partially in contact with the surface of the battery body at the second notch of the sub-gate of another polarity.

[0012] In this embodiment, by designing a second notch in the sub-grid on the surface of the solar cell, a portion of the insulating adhesive can be omitted at this location. From the perspective of the entire solar cell and photovoltaic module, this results in significant savings in insulating adhesive, helping to reduce its cost. Simultaneously, eliminating the need for extensive adhesive application at the second notch saves processing time, shortening the manufacturing time of the photovoltaic module and increasing its shipment volume. Furthermore, removing some insulating adhesive at the second notch helps reduce the height difference between the top of the interconnect strip and the top of the sub-grid, reducing internal stress in the laminate and improving the overall quality of the photovoltaic module.

[0013] Furthermore, when stringing interconnects, the interconnects can be connected to the corresponding polarity sub-grids via the connecting portion. Compared to the connection design between the interconnects and the sub-grids, the connecting portion provides a larger welding area, offering greater adhesion for the interconnects and making the connection between the interconnects and the cells more reliable. The larger welding area also helps reduce welding resistance, thereby lowering the power loss of the cells.

[0014] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 shows a schematic diagram of the structure of the solar cell in an embodiment of this application;

[0017] Figure 2 shows a schematic diagram of the location of the connection portion of the solar cell in an embodiment of this application;

[0018] Figure 3 shows a schematic diagram of the connection between the solar cell and the interconnecting strip in an embodiment of this application;

[0019] Figure 4 shows a schematic diagram of the gap formed between the interconnecting strip and the insulating adhesive in an embodiment of this application;

[0020] Figure 5 shows a schematic diagram in which the interconnecting strip and the insulating adhesive do not form a gap in an embodiment of this application;

[0021] Figure 6 shows a schematic diagram of the interconnecting strip and insulating adhesive layer in an embodiment of this application;

[0022] Figure 7 shows a schematic diagram of a structure in which the sub-gate at the connecting part is continuously connected in an embodiment of this application;

[0023] Figure 8 shows a schematic diagram in which the width of the interconnecting strip at the connecting part is greater than the width of the interconnecting strip at the second notch in an embodiment of this application;

[0024] Figure 9 shows a partial structural schematic diagram of the solar cell in an embodiment of this application;

[0025] Figure 10 shows a partial structural schematic diagram of the solar cell in an embodiment of this application;

[0026] Figure 11 shows a partial structural schematic diagram of the solar cell in an embodiment of this application;

[0027] Figure 12 shows a complete schematic diagram of the electrode structure on the surface of a battery cell in an embodiment of this application;

[0028] Figure 13 is a partially enlarged schematic diagram of position I in Figure 12 in an embodiment of this application;

[0029] Figure 14 shows a second schematic diagram of the structure of the solar cell in an embodiment of this application;

[0030] Figure 15 shows a schematic diagram of the structure of the solar cell in an embodiment of this application;

[0031] Figure 16 shows a schematic diagram of the structure of the solar cell in an embodiment of this application;

[0032] Figure 17 shows a schematic diagram of the shape of the connecting part in an embodiment of this application;

[0033] Figure 18 shows a second schematic diagram of the shape of the connecting part in an embodiment of this application;

[0034] Figure 19 shows a schematic diagram of the shape of the connecting part in an embodiment of this application.

[0035] Reference numerals: Battery body - 10, First side - 10a, Second side - 10b, Electrode structure - 101, First notch - 102b, Second notch - 102a, Interconnecting strip - 103, Connecting part - 104, First unipolar unit - 105, Sub-grid - 1011, Positive electrode sub-grid - 1011a, Negative electrode sub-grid - 1011b, End main grid - 1012, Middle main grid - 1013, Edge main grid - 1014, Insulating adhesive - 1015, First connecting part - 1016, Second connecting part - 1017, Edge interconnecting strip on the left edge - 1031, Edge interconnecting strip on the right edge - 1032. Specific Implementation

[0036] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0037] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0038] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0039] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0040] The photovoltaic modules provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0041] In the photovoltaic module of this application embodiment, the electrode structure on the surface of the cells forming the cell string is optimized and improved. This eliminates the need for extensive application of insulating adhesive when the interconnecting strips pass over certain areas of the cell surface during string bonding, thus reducing adhesive consumption. Compared to traditional photovoltaic modules, since a large amount of insulating adhesive is no longer required on certain areas of the cell surface, the cost of the insulating adhesive is naturally reduced. Furthermore, the time spent on adhesive application is saved, contributing to improved manufacturing efficiency of the photovoltaic module.

[0042] Figure 1 shows a schematic diagram of the structure of a solar cell used in a photovoltaic module according to an embodiment of this application. The cell body 10 can be a silicon wafer made of monocrystalline silicon or polycrystalline silicon. The shape of the cell body 10 can be a rectangle with a first side 10a and a second side 10b. The first side 10a and the second side 10b can be two mutually perpendicular sides of the rectangular silicon wafer. For example, the first side 10a can be the long side of the rectangle, and the second side 10b can be the short side of the rectangle. The extension direction of the first side 10a is the X direction shown in the figure, and the extension direction of the second side 10b is the Y direction shown in the figure.

[0043] An electrode structure 101 is provided on the surface of the battery body 10. Exemplarily, the electrode structure 101 can be prepared by screen printing or electroplating. The electrode structure 101 includes multiple sub-grids 1011 distributed on the battery body 10. The sub-grids 1011 are typically thin and can also be referred to as fine grids. These sub-grids 1011 can include two types of sub-grids with opposite polarities: a positive sub-grid 1011a and a negative sub-grid 1011b. Referring to the illustration in Figure 1, all sub-grids 1011 can be partially or completely parallel to the first side 10a, and the positive sub-grid 1011a and negative sub-grid 1011b can be alternately arranged along the extending direction Y of the second side 10b.

[0044] As shown in Figures 1 and 2, Figure 2 illustrates the surface structure of the battery cell after the connection portion 104 is fabricated based on Figure 1. In this embodiment, whether it is the positive electrode sub-gate 1011a or the negative electrode sub-gate 1011b, along the extension direction X of the first side 10a, the sub-gate 1011 includes multiple second notches 102a and multiple connection portions 104 (see Figure 2 for the connection portion 104). The second notches 102a are empty and disconnected structures. There is no conductive medium at the location of the second notches 102a, thus the sub-gate 1011 is broken into multiple segments. However, at the location of the connection portion 104, the sub-gate 1011 remains conductive. Exemplarily, the connection portion 104 can be a solder pad. The second notches 102a and the connection portions 104 are arranged adjacent to each other on the same sub-gate 1011 along the first side 10a, and the second notches 102a and the connection portions 104 can each be located at both ends of the same segment of the sub-gate 1011. Furthermore, along the extension direction of the second side 10b, the second notch 102a and the connecting portion 104 on the two adjacent sub-gates 1011 are arranged adjacent to each other.

[0045] In conjunction with the above embodiments, it should also be noted that, in the embodiments of this application, when counting the number of sub-gates 1011, gate lines that coincide along the X direction are considered as the same sub-gate 1011. The portions of the same sub-gate 1011 separated by the second notch 102a are different segments of the sub-gate 1011.

[0046] Referring to the illustration in Figure 2, it can be understood that along the X direction, the sub-grid 1011 forms a shape structure of "grid line - connector - grid line - second notch - grid line - connector - grid line - second notch - grid line - connector - grid line". In the actual processing and manufacturing of this type of battery cell, the connector 104 and the sub-grid 1011 can be printed in the same process or printed in separate steps in different processes.

[0047] Figure 3 also shows a schematic diagram of interconnecting strips 103 laid on the surface of one of the battery cells when multiple interconnecting strips 103 are used for string welding. The interconnecting strips 103 are all arranged along the extension direction of the second side 10b, connecting adjacent battery bodies 10 arranged in the Y direction together.

[0048] Referring to the illustration in Figure 3, when any interconnecting strip 103 is laid along the Y direction as shown, it electrically connects the connecting portions 104 of one polarity of the sub-gate 1011 together. When the interconnecting strip 103 passes through the second notch 102a of the sub-gate 1011 of another polarity, it remains insulated and disconnected from the sub-gate 1011 of the other polarity. Along the extension direction of the second side 10b (i.e., the Y direction), which is also the extension direction of the interconnecting strip 103, the connecting portions 104 on at least one sub-gate 1011 are alternately arranged with the second notch 102a on another sub-gate 1011. For example, in Figure 2, along the Y direction, the connecting portions 104 on the positive sub-gate 1011a are alternately arranged with the second notch 102a on the negative sub-gate 1011b. Thus, a shape characteristic of "connecting portion-second notch-connecting portion-second notch-connecting portion-second notch" is formed in the Y direction.

[0049] Because of the design of the second notch 102a, the interconnect strip 103 is insulated from the sub-gate 1011 of the other polarity. Therefore, at the second notch 102a, the interconnect strip 103 is at least partially in contact with the surface of the battery body 10. In other words, at the second notch 102a, it is not necessary to apply a large amount of insulating adhesive; the interconnect strip 103 can simply be in direct contact with the battery body 10 at least partially. The interconnect strip 103 may include a core material and an outer welding layer such as a tin alloy layer. At the second notch 102a, the interconnect strip 103 is in contact with the passivation layer (such as a silicon nitride layer, an aluminum oxide layer, etc.) and TCO layer of the battery body 10. There may be no electrode structure or insulating adhesive between the interconnect strip 103 and the battery body 10.

[0050] Therefore, by designing a second notch in the sub-grid on the surface of the solar cell in this embodiment, a portion of the insulating adhesive can be omitted at this location. From the perspective of the entire solar cell and photovoltaic module, this results in significant savings in insulating adhesive, helping to reduce its cost. Simultaneously, eliminating the need for extensive application of insulating adhesive at the second notch saves processing time, shortening the manufacturing time of the photovoltaic module and increasing its shipment volume. Furthermore, the removal of some insulating adhesive at the second notch helps reduce the height difference between the top of the interconnect strip and the top of the sub-grid, reducing internal stress in the laminate and improving the overall quality of the photovoltaic module.

[0051] Furthermore, when interconnecting strips are laid out along the Y direction for string welding, the interconnecting strips can be welded to the corresponding polarity sub-grids through the connecting parts. Compared to the welding design of interconnecting strips and sub-grids, the connecting parts can provide a larger welding area, providing greater adhesion for the interconnecting strips and making the connection between the interconnecting strips and the solar cells more reliable. Moreover, the larger welding area also helps to reduce welding resistance, thereby reducing the power loss of the solar cells.

[0052] Optionally, in one embodiment, when laying the interconnect strip 103, to prevent accidental short circuits caused by the interconnect strip 103 shifting with the sub-grid 1011 next to the second notch 102a, a small amount of insulating adhesive 1015 can be applied to the second notch 102a to further improve insulation reliability. Specifically, within the allowable range of process errors, when the degree of shift of the interconnect strip 103 is different, the interconnect strip 103 and the insulating adhesive 1015 in the photovoltaic module can form the following different positional relationships:

[0053] a) As shown in Figure 4, when the degree of offset of the interconnecting strip 103 is small along the extension direction of the first side 10a (i.e., the X direction in the figure), the interconnecting strip 103 can still maintain a certain gap with the insulating adhesive 1015. At this time, along the thickness direction Z of the battery body 10, there is no insulating adhesive 1015 between the interconnecting strip 103 and the battery body 10, and the interconnecting strip 103 is in direct contact with the battery body 10. At this time, the physical insulation distance between the interconnecting strip 103 and the sub-grid 1011 with opposite polarity is large, and it has better insulation performance.

[0054] (b) As shown in Figure 5, when the interconnecting strip 103 is significantly offset along the extension direction of the first side 10a (i.e., the X direction in the figure), the interconnecting strip 103 just touches the edge of the insulating adhesive 1015, and there is no gap between the interconnecting strip 103 and the insulating adhesive 1015 along the X direction. At this time, along the thickness direction Z of the battery body 10, there is still no insulating adhesive 1015 between the interconnecting strip 103 and the battery body 10, and the interconnecting strip 103 is in direct contact with the battery body 10. At this time, even if the interconnecting strip 103 is offset, under the insulation and isolation effect of the insulating adhesive 1015, the interconnecting strip 103 and the sub-grid 1011 with opposite polarity can still have good insulation performance.

[0055] It should be understood that certain process errors are inevitable in actual production. At this time, the main body of the interconnecting strip 103 is in direct contact with the battery body 10, and the edge of the interconnecting strip 103 will overlap with the insulating adhesive 1015 (as shown in Figure 6). It is understandable that this overlapping structure can still ensure insulation performance within the allowable range of process errors.

[0056] Optionally, in one embodiment, as shown in Figures 1 and 2, in the battery cell of this application embodiment, along the extending direction X of the first side 10a, the sub-gate 1011 further includes a plurality of first notches 102b. Similar to the second notch 102a in the aforementioned embodiment, the sub-gate 1011 at the location of the first notch 102b can also be a discontinuous structure. However, since the interconnecting strip 103 needs to be electrically connected to the sub-gate 1011 of the same polarity when passing through the location of the first notch 102b, the aforementioned connecting portion 104 is provided at the location of the first notch 102b. The connecting portion 104 can connect and conduct the separated sub-gates 1011. Thus, when the interconnecting strip 103 is welded to the connecting portion 104, an electrical connection can be established with the sub-gate 1011 at that location.

[0057] In this type of battery cell, due to the design of the first notch 102b, the consumption of paste used for printing the sub-grid 1011 can be further reduced, thus saving the cost of the sub-grid 1011 paste.

[0058] Optionally, in one embodiment, as shown in FIG7, to prevent the sub-gate 1011 from failing to conduct effectively at the first notch 102b due to the presence of the first notch 102b and the subsequent printing of the connecting portion 104 at the location of the first notch 102b, the embodiment of this application may further design the sub-gate 1011 at the location of the connecting portion 104 as a continuous structure. That is, the gate line at this location is not separated by the first notch 102b, and the connecting portion 104 is directly printed and covers the continuous gate line. In this case, the electrical contact area between the connecting portion 104 and the sub-gate 1011 is larger, which is more conducive to the current transmission of the sub-gate 1011 to the connecting portion 104. It should be noted that the continuous structure of the sub-gate 1011 in the embodiment of this application refers to a design structure opposite to that with the first notch 102b. It means that the gate line of the sub-gate 1011 remains continuous at the location where the first notch 102b was originally, and does not mean that a complete sub-gate 1011 is continuously continuous along the X direction shown in the figure.

[0059] Optionally, in one embodiment, when the interconnect strip 103 is laid across the connecting portion 104, solder paste or other materials can be used to weld the interconnect strip 103 to the connecting portion 104, and the interconnect strip 103 and the connecting portion 104 can be directly contacted and electrically connected. The interconnect strip 103 includes a core material and a solder layer covering the surface of the core material. For example, when tin-plated copper solder strip is used as the interconnect strip 103, the tin plating layer on the surface of the interconnect strip 103 can be melted, so that the interconnect strip 103 and the connecting portion 104 are welded and fixed together. This photovoltaic module of the present application embodiment can reduce the consumption of solder paste and other soldering materials, and reduce the process cost of string soldering. It can be understood that the fixation between the interconnect strip 103 and the connecting portion 104 does not rely on other soldering materials. Of course, residual components of pretreatment such as surface cleaners are not considered as soldering materials between the interconnect strip 103 and the connecting portion 104. At this time, the interconnecting strip 103 directly contacts the battery body 10 at the connection part 104 and the second notch 102a, which can save insulating glue and welding materials at the same time, reduce the height of the interconnecting strip 103 relative to the battery body 10, and enhance the bonding strength between the interconnecting strip 103 and the battery body 10.

[0060] As can be seen from the above two embodiments, the sub-gate 1011 at the connection part 104 can be continuous or disconnected, and can be selected according to different functional requirements.

[0061] Optionally, in one embodiment, when the interconnecting strip 103 is laid along the extension direction of the second side 10b (i.e., the Y direction in the figure), the interconnecting strip 103 has a first bottom at the position of the connecting portion 104, a second bottom at the position of the second notch 102a, and a third bottom at the position of the interconnecting strip 103 outside the connecting portion 104 and the second notch 102a. The bottom of the interconnecting strip 103 refers to the portion adjacent to the battery body 10 along the thickness direction of the battery body 10. In the same interconnecting strip 103, along the thickness direction of the battery body 10, the height difference between any two bottoms among the first bottom, the second bottom, and the third bottom is less than or equal to 0.5 mm. For example, the height difference between any two bottoms can 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. Therefore, when the interconnecting strip 103 is laid along the Y direction as shown in the figure, all parts of the interconnecting strip 103 can be kept as close to the same horizontal plane as possible, preventing the interconnecting strip 103 from forming large bending deformations in the thickness direction of the battery body 10, and improving the resulting problem of poor soldering. In some embodiments, the above-mentioned height difference is less than or equal to 50μm, which can make the photovoltaic module have higher quality. For example, the height difference between any two bottoms can be 10μm, 15μm, 20μm, 25μm, 30μm, 35μm, 40μm, 45μm, or 50μm. Further, the height difference between the bottoms of adjacent interconnecting strips 103 is less than or equal to 90μm. This can make the welding height and welding performance differences between multiple interconnecting strips 103 smaller under the same process and the same technological conditions. For example, the height difference at the bottom of adjacent interconnecting strips 103 can be 10μm, 20μm, 30μm, 40μm, 50μm, 60μm, 70μm, 80μm or 90μm.

[0062] Optionally, in one embodiment, as shown in FIG8, within the same interconnecting strip 103, along the extending direction of the first side 10a (i.e., the X direction in the figure), the interconnecting strip 103 has a first width W1 at the position of the connecting portion 104, and a second width W2 at the position of the second notch 102a, wherein the first width W1 is greater than the second width W2. This design results in a larger contact area between the wider portion of the interconnecting strip 103 and the connecting portion 104, leading to better connection strength. In some embodiments, the first width W1 is at least 1.3 times the second width W2. The first and second widths here include the welding layer of the interconnecting strip 103. Furthermore, the first width located in the edge region of the battery body 10 is greater than the first width located in the central region of the battery body 10.

[0063] Optionally, in one embodiment, along the extension direction of the first side 10a (i.e., the X direction in the figure), the first notch 102b has a first length, and the second notch 102a has a second length, the second length being greater than the first length. This differentiated dimensional design helps ensure sufficient clearance between the interconnecting strip 103 and the grid lines on both sides of the second notch 102a, and that the distance between the electrically connected interconnecting strip 103, connecting portion 104, and sub-grid 1011 is small, resulting in less electrical loss. For example, on the battery body 10, each second length may be greater than the first length, or the second length in the end region of the battery cell may be greater than the first length, while the second length in other regions may be approximately equal to the first length.

[0064] Optionally, in one embodiment, the second notch 102a has a second length along the extending direction of the first side 10a (i.e., the X direction in the figure). When the interconnecting strip 103 used in the embodiments of this application is a circular wire interconnecting strip with a circular cross-section, the second length is at least twice the diameter of the circular wire interconnecting strip.

[0065] When the interconnecting strip 103 used in this embodiment is a flat wire interconnecting strip with a rectangular cross-section, the second length is at least 1.5 times the width of the flat wire interconnecting strip. Compared to flat wire interconnecting strips, round wire interconnecting strips typically have a smaller diameter and a smaller contact area with the battery body 10, making them prone to rolling and shifting. Therefore, when using round wire interconnecting strips, a larger gap can be designed between the round wire interconnecting strip and the sub-grid 1011 of the second notch 102a. Flat wire interconnecting strips typically have a relatively larger contact area with the battery body 10, and the rectangular interconnecting strip 103 has relatively smaller shift and is less prone to rolling. A relatively smaller gap can be designed between it and the adjacent sub-grid 1011 of opposite polarity to increase the current collection effect of the sub-grid 1011. In this case, dot-shaped or block-shaped insulating adhesive can be provided on both sides of the interconnecting strip 103 at the ends of the sub-grid 1011 of opposite polarity, or no insulating adhesive can be provided.

[0066] Optionally, in one embodiment, at the second notch 102a, along the extension direction of the first side 10a (i.e., the X direction in the figure), the spacing between the ends of the interconnecting strip 103 and the two side sub-gates 1011 can be the same or different, with the sum of the spacings on both sides ranging from 200μm to 600μm. For example, it can be 200μm, 300μm, 400μm, 500μm, or 600μm. Here, "two side sub-gates" can refer to sub-gates 1011 located on both sides of the interconnecting strip 103, with opposite polarity to the interconnecting strip 103, or requiring insulation. When the specific shape of the interconnecting strip 103 is uncertain, a certain safety distance can be reserved between the interconnecting strip 103 and the sub-gates 1011 to ensure insulation.

[0067] Optionally, in one embodiment, the second notch 102a has a second length along the extension direction of the first side 10a (i.e., the X direction in the figure). Along the extension direction of the second side 10b (i.e., the Y direction in the figure), the second length of the second notch 102a near the edge of the battery body 10 is greater than the second length of the second notch 102a located in the middle of the battery body 10. The offset at both ends of the interconnect strip 103 is often greater than that in its middle. The second notch 102a near the edge of the battery body 10 corresponds to the cut-off end portion of the interconnect strip 103. Designing the second length of the second notch 102a at this location to be greater than the second length of the second notch 102a in the middle region of the battery body 10 can improve the tolerance during the laying of the interconnect strip 103 end portion and reduce the likelihood of short circuits at the end of the interconnect strip 103.

[0068] Optionally, in one embodiment, as illustrated in FIG4, insulating adhesive 1015 is provided at the end of the sub-gate 1011 forming the second notch 102a. The minimum distance between the two insulating adhesives 1015 corresponding to the second notch 102a can be 1.8 mm, and the maximum distance can not exceed 5 mm. For example, the distance can be 1.8 mm, 1.9 mm, 2 mm, 3 mm, 4 mm, or 5 mm. The distance between the two insulating adhesives 1015 can be the shortest gap between the edges of the two insulating adhesives 1015. When the gap is 1.8 mm, the distance is small, and the second width corresponding to the second notch 102a is also narrow, that is, the ends of the sub-gate 1011 on both sides of the second notch 102a are closer together, which is beneficial to the collection of current by the sub-gate 1011. When the gap is 5mm, the spacing is relatively large, and the second width corresponding to the second notch 102a is also relatively wide. That is, the ends of the sub-grids 1011 on both sides of the second notch 102a are further apart, and there is enough space between the two insulating adhesives 1015 to place the interconnecting strip 103. The interconnecting strip 103 can be in complete direct contact with the battery body 10.

[0069] Optionally, in one embodiment of this application, the paste used when printing the sub-gate 1011 can be a burn-through type paste, and the paste used when printing the connecting portion 104 can be a non-burn-through type paste. The connecting portion 104 cannot penetrate the passivation layer on the surface of the battery body 10. Therefore, at the location of the first notch 102b, the end of the sub-gate 1011 overlaps and connects with the connecting portion 104, and the end of the sub-gate 1011 is at least partially located on the side of the connecting portion 104 facing away from the battery body 10. That is, the end of the sub-gate 1011 overlaps the upper layer of the connecting portion 104. On the one hand, this ensures sufficient contact between the sub-gate 1011 and the connecting portion 104, improving electrical connection performance. On the other hand, the protruding ends of the sub-gate 1011 can act as a limiting interlocking strip 103.

[0070] In some embodiments, at the connection portion 104, the sub-gate 1011 may press against the surface of the connection portion 104 and protrude from the surface of the connection portion 104, or the connection portion 104 may cover the sub-gate 1011, with a portion of the connection portion 104 being lifted up by the sub-gate 1011.

[0071] Optionally, in one embodiment, as illustrated in FIG3, along the extension direction of the first side 10a (i.e., the X direction in the figure), the interconnecting strip 103 includes a middle interconnecting strip 103, an edge interconnecting strip 1031 on the left edge, and an edge interconnecting strip 1032 on the right edge. At any point where an edge interconnecting strip passes, a sub-gate 1011 with the opposite polarity to the edge interconnecting strip continuously extends through it, and an insulating adhesive 1015 is provided between the edge interconnecting strip and the sub-gate 1011 with the opposite polarity.

[0072] Referring to the illustration in Figure 3, taking the edge interconnecting strip 1032 on the right edge as an example, the edge interconnecting strip 1032 on the right edge is laid along the Y direction shown in the figure, electrically connecting each positive electrode sub-gate 1011a together through corresponding multiple connecting parts 104. The negative electrode sub-gate 1011b between two adjacent positive electrode sub-gates 1011a has a continuous through-structure in the part where the edge interconnecting strip 1032 passes. To prevent these negative electrode sub-gates 1011b from short-circuiting with the edge interconnecting strip 1032, insulating adhesive 1015 is provided below the edge interconnecting strip 1032 and on the continuous through-structure of the negative electrode sub-gates 1011b. It should be understood that the battery body 10 can adopt the design shown in Figure 3 entirely, or it can adopt the design shown in Figure 3 partially.

[0073] Optionally, in one embodiment, when the edge interconnect strip is connected to the connecting part 104, a conductive layer such as solder paste can be applied to the upper layer of a portion of the connecting part 104. The welding effect of the conductive layer can make the fixed connection between the edge interconnect strip and the connecting part 104 more reliable.

[0074] Optionally, in one embodiment, as illustrated in FIG3, along the extension direction of the first side 10a (i.e., the X direction in the illustration), the interconnecting strip 103 includes a middle interconnecting strip 103, an edge interconnecting strip 1031 on the left edge, and an edge interconnecting strip 1032 on the right edge. Referring to FIG9, the electrode structure 101 also includes an edge main grid 1014 near the edge of the battery body 10; the edge main grid 1014 is closer to the edge of the battery body 10 than the edge interconnecting strips. Referring to FIG9, that is, the edge main grid 1014 is closer to the outer side of the battery body 10 than the edge interconnecting strips.

[0075] As shown in Figure 9, among the sub-gates 1011 connected to the edge main gate 1014, a portion of the sub-gates 1011 are continuously connected. These continuously connected sub-gates 1011 electrically connect the edge main gate 1014 to the connecting portion 104 of the same polarity located inside the edge main gate 1014. The current collected by the edge main gate 1014 can be transmitted to the left through the continuously connected sub-gates 1011 to another adjacent interconnecting strip 103 from right to left.

[0076] Meanwhile, the edge interconnecting strip 1031 on the left edge and the edge interconnecting strip 1032 on the right edge are each arranged along the extension direction of the second side 10b (i.e., the Y direction in the figure). Taking an edge interconnecting strip laid on the left side of the edge main grid 1014 as an example, the edge interconnecting strip in this part is electrically connected to the positive sub-grid 1011a, and the negative sub-grid 1011b is electrically connected to the edge main grid 1014. At this time, it can be understood that a continuous grid line structure can be designed on part of the negative sub-grid 1011b. In order to avoid short circuits when the edge interconnecting strip passes through the negative sub-grid 1011b and its continuous connection part, an insulating adhesive 1015 is provided between the continuously connected negative sub-grid 1011b and the edge interconnecting strip.

[0077] In Figure 9, the arrow next to the sub-gate 1011 shows the current transmission path near the end of the second side 10b through the edge main gate 1014 and the continuously connected sub-gate 1011. Referring to the illustration in Figure 9, it is easy to understand that the edge main gate 1014 can be electrically connected to multiple continuously connected sub-gates 1011, forming multiple parallel current transmission paths at different locations near the second side 10b of the cell. The current transmission path direction is generally along the X direction. Current is transmitted between the edge interconnect 1032 on the right edge and another interconnect 103 adjacent to the edge interconnect 1032. The current transmission direction is from the edge interconnect 1032 to the other interconnect 103 adjacent to the edge interconnect 1032. The current transmission path direction can include one, two, or more, and each current transmission path is independent of the others, thereby enabling comprehensive and complete current collection in different areas of the cell edge, reducing power loss. At this point, at the edge interconnection strip, some sub-gates 1011 are disconnected while others are continuously connected, which can further reduce the material loss of the insulating adhesive and conductive layer in the edge region. Furthermore, the fewer continuously connected sub-gates 1011 used for current transmission in the edge main gate 1014, the more insulating adhesive and conductive layer material is saved. Preferably, one or two continuously connected sub-gates 1011 are provided at both ends of the edge main gate 1014.

[0078] Optionally, in one embodiment, as shown in FIG10, an insulating adhesive 1015 is provided between the continuously connected sub-gate 1011 and the edge interconnecting strip. When the edge interconnecting strip extends along the Y direction shown in the figure and is electrically connected to at least one sub-gate 1011 near the continuously connected sub-gate 1011, poor contact is more likely to occur due to the height difference. Therefore, in this embodiment, the electrode structure 101 further includes a first connecting portion 1016. The function of the first connecting portion 1016 is similar to the grid line of the main grid in a conventional battery cell. At least one sub-gate 1011 near the continuously connected sub-gate 1011 is electrically connected to the adjacent connecting portion 104 through the first connecting portion 1016 to form a first unipolar unit 105. The provision of the first connecting portion 1016 can ensure that when the welding reliability between the sub-gate 1011 near the continuously connected sub-gate 1011 and the interconnecting strip 103 is weak, the current can be transmitted through the first connecting portion 1016 to the adjacent connecting portion 104, and then conducted to the corresponding edge interconnecting strip.

[0079] Furthermore, when the edge interconnect strip is electrically connected to at least one sub-gate 1011 adjacent to the continuously connected sub-gate 1011, the other sub-gate 1011 adjacent to the continuously connected sub-gate 1011 can be continuously connected without a connecting portion 104, or a connecting portion 104 can be provided and the connecting portion 104 directly contacts the edge interconnect strip without a conductive layer. For example, taking FIG10 as an example, the continuously connected sub-gate 1011 can be the negative electrode sub-gate 1011b shown in FIG10, and the sub-gate 1011 adjacent to it can be the positive electrode sub-gate 1011a shown in FIG10. When the positive electrode sub-gate 1011a is continuously connected, it can be without a connecting portion 104, or it can be provided with a connecting portion 104. When a connecting portion 104 is provided, the edge interconnect strip directly contacts the connecting portion 104 on the positive electrode sub-gate 1011a without a conductive layer. As shown in Figure 10, when the first connecting part 1016 is long, multiple sub-gates 1011 can be connected. At both ends of the length direction of the first connecting part 1016, a continuous negative sub-gate 1011b is provided. Multiple positive sub-gates 1011a are distributed between the two continuous negative sub-gates 1011b. The first connecting part 1016 can connect these positive sub-gates 1011a to some units forming the first unipolar unit 105.

[0080] It is understandable that when the continuously connected sub-gate 1011 is a positive sub-gate 1011a, then the non-polar sub-gate can be a negative sub-gate 1011b, and vice versa. In this case, the first connecting portion 1016 connects multiple non-polar sub-gates together to form a first unipolar unit 105. This first unipolar unit 105 can be either a positive or negative electrode. Current is collected by the multiple sub-gates 1011 extending in the X direction, and then collected again through the first connecting portion 1016 onto the interconnecting strip at that location. This avoids the risk of damage to the sub-gates 1011 when the interconnecting strip is directly welded to each sub-gate. Simultaneously, the first connecting portion 1016 and the interconnecting strip can form a redundant backup protection structure, preventing localized failure of the interconnecting strip's current collection when used alone, thus helping to improve the working stability and reliability of the solar cell.

[0081] Optionally, in one embodiment, as shown in FIG10, at least one connecting portion 104 is provided in the sub-gate 1011 electrically connected to the edge interconnecting strip, and the edge interconnecting strip is electrically connected to the sub-gate 1011 through the connecting portion 104. Referring to the illustration in FIG10, it can be understood that in the aforementioned first single-pole unit 105, at least one connecting portion 104 is provided to maintain the conduction of the corresponding sub-gate 1011, and a reliable connection between the corresponding sub-gate 1011 and the edge interconnecting strip can be achieved. As shown in FIG11, this embodiment further illustrates a schematic diagram of the first single-pole unit 105 having three connecting portions 104. With an increase in the number of connecting portions 104, it is more beneficial to improve the connection reliability between the edge interconnecting strip and the corresponding sub-gate 1011 in the first single-pole unit 105. In addition, to more intuitively illustrate a battery cell used in the embodiments of this application, Figure 12 also shows a complete arrangement diagram of the electrode structure 101 on the surface of the battery cell in the embodiments of this application, and Figure 13 is a partial enlarged diagram of position I in Figure 12. As can be seen, Figure 13 at least shows the second side 10b, the second notch 102a, the connecting part 104, the positive electrode sub-gate 1011a, the negative electrode sub-gate 1011b, the first connecting part 1016 and the second connecting part 1017 in the embodiments of this application, as well as the position and connection relationship of these structures described in the foregoing embodiments.

[0082] Optionally, in one embodiment, for any of the edge interconnecting strips 1031 on the left edge and 1032 on the right edge, when connecting to the connecting portion 104, solder paste or similar materials can be omitted to directly contact and electrically connect the interconnecting strip 103 and the connecting portion 104. This further saves on conductive layer material in the edge region. Furthermore, the ends of the sub-gates 1011 with opposite polarities on both sides of the edge interconnecting strip can be provided with dot-shaped or block-shaped insulating adhesive, or no insulating adhesive can be provided at all, with gap insulation between the ends of the edge interconnecting strip and the sub-gate 1011.

[0083] Optionally, in one embodiment, the spacing between a set of edge interconnect strips and the edge main grid 1014 on the same side of the cell, along the extending direction of the first side 10a (i.e., the X direction in the figure), is 2mm to 6mm. For example, referring to the illustrations in Figures 3 and 9, the spacing between the edge interconnect strip 1032 on the right edge and the edge main grid 1014 can be 2mm, 2.5mm, 3mm, 3.5mm, 4mm, 4.5mm, 5mm, 5.5mm, or 6mm. It is understood that if the spacing is too small, it is not conducive to the laying and arrangement of the edge interconnect strip 1032 on the right edge, and it is easy for it to come into contact with the edge main grid 1014. If the spacing is too large, it is easy to affect the overall arrangement density of the interconnect strips 103 in the battery string. Therefore, the specific value of the above spacing can be determined according to the specifications and dimensions of the cell and the arrangement density of the interconnect strips 103 in the battery string.

[0084] Optionally, in one embodiment, as shown in FIG9, in the sub-gate 1011 which is insulated from the edge interconnection strip, a portion of the sub-gate 1011 is provided with a second notch 102a, and another portion of the sub-gate 1011 is a continuous sub-gate.

[0085] Taking Figures 3 and 9 as examples, the edge interconnecting strip 1032 on the right edge is insulated from the negative electrode sub-gate 1011b. Specifically, insulation can be achieved in two different ways depending on the location of the negative electrode sub-gate 1011b. Some of these negative electrode sub-gates 1011b have a second notch 102a, which maintains insulation from the edge interconnecting strip 1032 on the right edge. Other negative electrode sub-gates 1011b are continuous structures. In this case, insulating adhesive 1015 can be applied at the intersection of the continuous negative electrode sub-gate 1011b and the interconnecting strip 103. Preferably, insulating adhesive 1015 is only applied to the continuous sub-gate 1011, that is, the sub-gate 1011 that generates current for the edge main gate 1014, so that the continuous sub-gate 1011 is not interrupted. For example, in Figure 9, the continuous sub-gate 1011 is the negative electrode sub-gate 1011b. It is understood that in some other embodiments, the continuously extending sub-gate 1011 may also be a positive sub-gate 1011a.

[0086] Optionally, in one embodiment, the more continuously connected sub-gates 1011 insulated from the edge interconnecting strip, the more insulating adhesive is required; conversely, fewer continuously connected sub-gates 1011 are detrimental to current collection. Therefore, in the embodiments of this application, the number of continuously connected sub-gates 1011 can be from 1 to 10, for example, 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In some embodiments, the number of continuously connected sub-gates 1011 can be from 1 to 3. It should be understood that the number of continuously connected sub-gates 1011 here refers to the number of continuously connected sub-gates 1011 insulated from the edge interconnecting strip within the edge region of the cell adjacent to a second side 10b, that is, the number of continuously connected sub-gates 1011 connected to an edge main gate 1014.

[0087] Optionally, in one embodiment, as illustrated in Figures 3 and 9, in the sub-gate 1011 insulated from the edge interconnecting strip, the through sub-gate 1011 is connected to another interconnecting strip. Therefore, the width of the through sub-gate 1011 is greater than the width of the other sub-gates 1011, which can ensure that the through sub-gate 1011 has stronger overcurrent performance and reduce the risk of gate line burn-out when transmitting large current.

[0088] Optionally, in one embodiment, the aforementioned through-type sub-gate 1011 with a larger width can consist of two layers of gate lines: a bottom layer of gate lines printed on the surface of the battery body 10, and a top layer of gate lines printed on the side of the bottom gate lines away from the battery body 10, i.e., the top layer of gate lines is stacked and printed over the bottom layer of gate lines. The width of the top layer of gate lines is greater than the width of the bottom layer of gate lines or the other sub-gates, thereby enabling the through-type sub-gate 1011 to have a larger width.

[0089] It should also be noted that the paste used when printing the bottom grid lines and the top grid lines can be the same or different. For example, when printing the bottom grid lines of a normal width, the paste of the sub-grid is used and printed with the same width and synchronously as the sub-grid 1011. Then, when printing the wider top grid lines, the paste of the connecting part 104 can be replaced and printed synchronously with the connecting part 104.

[0090] Optionally, in one embodiment, as shown in FIG10, the electrode structure 101 in this application embodiment further includes a second connecting portion 1017. The second connecting portion 1017 can be connected to the interconnecting strip 103 in the middle of the battery cell. The second connecting portion 1017 can be located between two adjacent middle interconnecting strips 103. The function of the second connecting portion 1017 is similar to the grid line of the main grid in a conventional battery cell. The second connecting portion 1017 extends along the Y direction and can electrically connect multiple sub-grids with the same polarity to form multiple second monopole units.

[0091] Taking the structure shown in Figure 10 as an example, the second connecting portion 1017 is provided along the extending direction of the second side 10b. The second connecting portion 1017 electrically connects the through sub-gate 1011 to the connecting portion 104 of the same polarity to form a second unipolar unit. It should be noted that the through sub-gate 1011 comes from the sub-gate 1011 that is insulated from the edge interconnect strip, that is, from the sub-gate 1011 that is electrically connected to the edge main gate 1014. In some other embodiments, the second connecting portion 1017 has a similar function to the first connecting portion 1016, and the second unipolar unit and the first unipolar unit 105 can be the same. In this application, the second connecting portion 1017 can avoid the risk of damage to the sub-gate 1011 when the interconnect strip is directly welded to each sub-gate 1011. At the same time, the second connecting portion 1017 can also form a redundant backup protection structure with the interconnect strip, avoiding the partial failure of the interconnect strip when it is used alone, which helps to improve the working stability and reliability of the battery cell.

[0092] Optionally, in one embodiment, a gap region is provided between two adjacent sub-grids 1011 with opposite polarities. This gap region is commonly referred to as a gap area, which is also the isolation area between the PN regions on the battery. Along the thickness direction of the battery body 10, an insulating adhesive 1015 is provided between the edge interconnect strip and the through sub-grid 1011, and the insulating adhesive 1015 at least partially covers the aforementioned gap region. In this structure, when using the same amount of insulating adhesive 1015, the area covered by the insulating adhesive 1015 is larger, and its thickness is reduced. This helps to reduce the height difference between the insulating adhesive 1015 and the connection portions 104 on both sides, which can improve the welding effect between the interconnect strip 103 and the connection portions 104 on both sides of the insulating adhesive 1015.

[0093] Optionally, referring to Figures 14 and 15, the electrode structure 101 further includes multiple end main grids 1012; along the extension direction of the second side 10b, the end main grids 1012 of a predetermined length are provided near the first side 10a of the solar cell, and the end main grids 1012 are connected to at least two of the connecting portions 104.

[0094] Specifically, as shown in Figures 14 and 15, to ensure accurate and reliable electrical connections between adjacent cells during string bonding, the electrode structure 1011 in the cell of this embodiment further includes multiple end main grids 1012. An end main grid 1012 can at least mean a grid line located near the first side 10a of the cell, extending in the Y direction from the first side 10a towards the inside of the cell, and connecting with a portion of the sub-grids 1011. The end main grid 1012 can be relatively short, but slightly thicker than the sub-grids 1011.

[0095] Referring to the illustration in Figure 14, end main grids 1012 are provided on both sides (i.e., the upper and lower first sides 10a) near the two sides of the battery cell along the extension direction Y of the second side 10b. The end main grids 1012 at the top of Figure 14 can extend downward through the connecting portions 104 on multiple sub-grids 1011 of the same polarity. For example, when the end main grid 1012 is short, it can be connected to two connecting portions 104; when the end main grid 1012 is long, it can be connected to more than two connecting portions 104.

[0096] Therefore, by providing an end main grid 1012 near the first side 10a of the solar cell, accurate and reliable welding of the interconnecting strip to the solar cell can be ensured, and local failure of the interconnecting strip collecting current when using the interconnecting strip alone can be avoided, which helps to improve the working stability and reliability of the cell. In addition, the end main grid 1012 can be welded to two or more small-sized connecting parts 104. Compared with the larger area connecting part structure in traditional cells, the connecting part paste can also be appropriately saved, and the electrode structure cost is lower.

[0097] Referring to the illustration in Figure 13, an end main grid 1012 is provided at one end of the first side 10a of the battery cell, extending along the Y direction of the second side 10b. During string bonding, one end of the interconnecting strip used to connect two battery cells (e.g., the first and second battery cells) is connected to the end main grid 1012 on the first battery cell, and then extends along the Y direction, passing through the battery body 10 and the other end of the first battery cell, then across the gap between the first and second battery cells, until it reaches the end main grid 1012 of the second battery cell. Therefore, based on Figure 14, the interconnecting strip is not cut when it passes through the gap between the first and second battery cells, reducing the risk of welding deviations in the interconnecting strip arrangement. Furthermore, the end main grid 1012 near the gap can be omitted, further saving electrode paste for the end main grid 1012 and further reducing paste costs.

[0098] Optionally, referring to FIG14, the electrode structure 101 includes a plurality of intermediate main gates 1013; along the extending direction Y of the second side 10b, the intermediate main gates 1013 are electrically connected to a plurality of the connecting portions 104.

[0099] Specifically, in this application, the intermediate main grid 1013 at least means: a grid line between the edge interconnects 1031 and 1032 that connects at least two connection portions 104. Accordingly, when preparing the battery cell of the embodiment of this application, the aforementioned sub-grid 1011, second notch 102b, intermediate main grid 1013, and connection portion 104 can be formed by screen printing. The width of the intermediate main grid 1013 can be slightly thicker than the sub-grid 1011, while being thinner than the conventional main grid. Pre-printing the intermediate main grid 1013 and electrically connecting it to the connection portion 104 of the sub-grid 1011 of the same polarity can avoid the local failure of the interconnects collecting current when using interconnects alone, which helps to improve the working stability and reliability of the battery cell. It can also avoid the melting defect of the sub-grid 1011 caused by the small size of the connection portion 104 in the completely gridless scheme, and can appropriately improve the string soldering yield.

[0100] 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 that are not connected to the grid lines. Specifically, when preparing the solar cell of the embodiments of this application, the aforementioned sub-grid 1011, second notch 102a, and connecting portions 104 can be formed by screen printing. When string bonding is performed, the interconnecting strip is connected to the sub-grid 1011 of the same polarity through the connecting portions 104. The solar cell may include at least two connecting portions 104 that are not connected to the grid lines, that is, the aforementioned end grids and / or intermediate grids are not required. In this way, the interconnecting strip can be used to replace the grids, which can collect the current from the sub-grid 1011 and aggregate the current for output. Thus, this solar cell is a type of low-grid or gridless solar cell that can reduce the cost of grid paste.

[0101] Optionally, referring to Figures 14 to 16, the electrode structure 101 further includes a main grid, which includes an end main grid 1012 and / or an intermediate main grid 1013, and an insulating adhesive 1015 is provided at the intersection of the sub-grid 1011 with the interconnecting strip of opposite polarity or the main grid.

[0102] Specifically, referring to the schematic diagrams in Figures 14 and 15, the main grid includes an end main grid 1012. The polarity of the sub-grid 1011 connected to the end main grid 1012 or the interconnecting strip is opposite to the polarity of the other sub-grids 1011. Therefore, in order to avoid short circuits caused by contact at the intersection of the interconnecting strip 103 or the end main grid 1012 and the sub-grid 1011 when the interconnecting strip 103 or the end main grid 1012 is laid, insulating adhesive 1015 is provided at the intersection of the sub-grid 1011 of the battery cell and the interconnecting strip or the end main grid 1012 with opposite polarity.

[0103] Referring to the schematic diagram of Figure 16, the main grid includes an intermediate main grid 1013. The continuous through portion of the sub-grid 1011 can be printed and molded as a single unit with other portions of the sub-grid 1011 using the same paste. The polarity of the sub-grid 1011 connected to the interconnecting strip connected to the connecting portion 104 is opposite to the polarity of the continuous through sub-grid 1011. Therefore, to prevent short circuits caused by contact between the interconnecting strip and the intersection of the continuous through sub-grid 1011 during the installation of the interconnecting strip, as shown in Figure 16, an insulating adhesive 1015 is provided at the intersection of the intermediate main grid 1013 and the continuous through sub-grid 1011.

[0104] Optionally, referring to Figures 17 to 19, the battery cell in this embodiment is a back-contact battery cell; and / or, along the extending direction of the first side 10a, the maximum size of the connecting portion 104 is a, and a is not less than the width of the first notch 102b; along the extending direction of the second side 10b, the maximum size of the connecting portion 104 is b, and b is less than the spacing between two adjacent sub-gates 1011 with the same polarity.

[0105] Specifically, in this embodiment, the battery cell is a back-contact battery cell; simultaneously, for the various shapes of the connecting portion 104, 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' satisfy the following conditions: 'a' is not less than the width of the first notch 102b, thereby reliably connecting the two segments of the same polarity of the sub-gates 1011 on both sides of the first notch 102b together. Along the Y direction as shown in the figure, 'b' is less than the spacing between two adjacent sub-gates 1011 of the same polarity, thereby preventing short circuits between the sub-gate 1011 connected to the connecting portion 104 and another sub-gate 1011 of the opposite polarity adjacent in the Y direction. For example, 0.5mm ≤ a ≤ 6mm, 0.05mm ≤ b < 1mm.

[0106] In some embodiments, the connecting portion 104 may be symmetrical about the extension direction (which may be the X direction) of the sub-gate 1011. For example, when the connecting portion 104 is a rectangle as shown in FIG. 17, the maximum dimension 'a' of the connecting portion 104 along the X direction is the length of the rectangle, and the maximum dimension 'b' of the connecting portion 104 along the Y direction is the width of the rectangle, where 0.5mm ≤ a ≤ 6mm and 0.05mm ≤ b ≤ 1mm. When the connecting portion 104 is a similar rhombus as shown in FIG. 18, the maximum dimension 'a' of the connecting portion 104 along the X direction is the distance between the two short sides of the similar rhombus, where 0.5mm ≤ a ≤ 6mm, and the maximum dimension 'b' of the connecting portion 104 along the Y direction is the distance between the highest and lowest points of the similar rhombus, with the middle width of the rhombus being b, where 0.05mm ≤ b ≤ 1mm, preferably 0.1mm ≤ b ≤ 0.5mm. When the connecting part 104 is a combination of a rectangle and a trapezoid as shown in Figure 19, it also satisfies: 0.5mm≤a≤6mm, 0.05mm≤b≤1mm, and preferably, 0.1mm≤b≤0.5mm.

[0107] The shape and size of the connection portion 104 in this embodiment of the application can provide a larger welding contact area compared to the width of the sub-gate 1011. Compared to the conventional connection portion (pad), the welding contact area is relatively small, which can avoid the problem of low open circuit voltage caused by the large composite area of ​​the large connection portion and the silicon substrate of the battery cell, and can reduce current transmission power consumption.

[0108] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0109] The terms "an embodiment," "embodiment," or "one or more embodiments" as used herein mean that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment of this application. Furthermore, please note that the examples of the phrase "in one embodiment" do not necessarily all refer to the same embodiment.

[0110] Numerous specific details are set forth in the specification provided herein. However, it will be understood that embodiments of this application may be practiced without these specific details. In some instances, well-known methods, structures, and techniques have not been shown in detail so as not to obscure the understanding of this specification.

[0111] In the claims, any reference signs placed between parentheses should not be construed as limiting the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. The use of the words first, second, and third, etc., does not indicate any order. These words may be interpreted as names.

[0112] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A photovoltaic module, characterized by, include: Multiple battery bodies, each battery body including a first side and a second side; each battery body is provided with an electrode structure, the electrode structure including multiple sub-grids, each sub-grid being at least partially parallel to the first side and extending along the second side, with two types of sub-grids of opposite polarity alternately arranged; Along the extending direction of the first side, the sub-gate includes a plurality of second notches and a plurality of connecting portions; the plurality of second notches divide the sub-gate into multiple segments, wherein the second notch portion is a gap-off structure; along the extending direction of the first side and the second side, the second notches and the connecting portions are arranged adjacent to each other; Multiple interconnecting bars are arranged along the extension direction of the second side, connecting adjacent battery bodies in series; any one of the interconnecting bars is electrically connected to the connection portion of the sub-gate of one polarity, and at least partially in contact with the surface of the battery body at the second notch of the sub-gate of another polarity.

2. The photovoltaic module of claim 1, wherein, An insulating adhesive is provided at the second notch, and the interconnecting strip is in contact with the insulating adhesive along the extension direction of the first side.

3. The photovoltaic module of claim 1, wherein, An insulating adhesive is provided at the second notch, and there is a gap between the interconnecting strip and the insulating adhesive along the extension direction of the first side.

4. The photovoltaic module of claim 1, wherein, Along the extending direction of the first side, the sub-gate also includes a plurality of first notches, and the connecting portion is disposed at the positions of the plurality of first notches, the connecting portion connecting the sub-gate to the first notch portion.

5. The photovoltaic module of claim 1, wherein, The sub-gate is designed to be continuously connected at the connection point.

6. The photovoltaic module of claim 1, wherein, The interconnecting strip is in direct electrical contact with the connecting part.

7. The photovoltaic module of claim 1, wherein, The interconnecting strip has a first bottom at the location of the connecting portion, a second bottom at the location of the second notch, and a third bottom at the location of the interconnecting strip outside the connecting portion and the second notch; In the same interconnecting strip, along the thickness direction of the battery body, the height difference between any two of the first bottom, the second bottom, and the third bottom is less than or equal to 0.5 mm.

8. The photovoltaic module of claim 7, wherein, In the same interconnecting strip, along the thickness direction of the battery body, the height difference between any two of the first bottom, the second bottom, and the third bottom is less than or equal to 50 μm.

9. The photovoltaic module of claim 1, wherein, In the same interconnecting strip, along the extension direction of the first side, the interconnecting strip has a first width at the position of the connecting portion, and the interconnecting strip has a second width at the position of the second notch, wherein the first width is at least 1.3 times the second width.

10. The photovoltaic module of claim 4, wherein, Along the extension direction of the first side, the first notch has a first length, and the second notch has a second length, the second length being greater than the first length.

11. The photovoltaic module of claim 1, wherein, Along the extending direction of the first side, the second notch has a second length, and the interconnecting strip includes a circular wire interconnecting strip with a circular cross-section, the second length being at least twice the diameter of the circular wire interconnecting strip; or, the interconnecting strip includes a flat wire interconnecting strip with a rectangular cross-section, the second length being at least 1.5 times the width of the flat wire interconnecting strip.

12. The photovoltaic module of claim 1, wherein, At the second notch location, along the extension direction of the first side, the sum of the distances between the interconnecting strip and the ends of the sub-gates on both sides is 200μm-600μm.

13. The photovoltaic module of claim 1, wherein, Along the extending direction of the first side, the second notch has a second length; Along the extension direction of the second side, the second length of the second notch near the edge of the battery body is greater than the second length of the second notch located in the middle of the battery body.

14. The photovoltaic module according to claim 1, characterized in that, An insulating adhesive is provided at the end of the sub-gate that forms the second notch, and the spacing between the two insulating adhesives corresponding to the second notch is 1.8mm-5mm.

15. The photovoltaic module according to claim 4, characterized in that, At the location of the first notch, the end of the sub-gate overlaps and communicates with the connecting portion, and the end of the sub-gate is at least partially located on the side of the connecting portion away from the battery body.

16. The photovoltaic module according to any one of claims 1-15, characterized in that, Along the extending direction of the first side, the interconnecting strip includes an edge interconnecting strip close to the edge of the battery body; At the location traversed by the edge interconnecting strip, the sub-gate with the opposite polarity to the edge interconnecting strip is continuously penetrated, and an insulating adhesive is provided between the edge interconnecting strip and the sub-gate with the opposite polarity.

17. The photovoltaic module according to claim 16, characterized in that, The edge interconnect strip is fixed and electrically connected to at least a portion of the connecting portion via a conductive layer.

18. The photovoltaic module according to any one of claims 1-15, characterized in that, Along the extending direction of the first side, the interconnecting strip includes an edge interconnecting strip near the edge of the battery body, and the electrode structure also includes an edge main grid near the edge of the battery body; the edge main grid is closer to the edge of the battery body than the edge interconnecting strip; The edge interconnecting strip is arranged along the extension direction of the second side. The edge interconnecting strip is electrically connected to the sub-gate of one polarity, and the sub-gate of the other polarity is electrically connected to the edge main gate. The edge main gate is electrically connected to the connecting part of the same polarity located inside the edge main gate through the continuously penetrating sub-gate. Insulating adhesive is provided between the edge interconnecting strip and the continuously penetrating sub-gate.

19. The photovoltaic module according to claim 18, characterized in that, The electrode structure further includes a first connecting portion, which is disposed along the extending direction of the second side; In the sub-gate electrically connected to the edge interconnection strip, along the extension direction of the second side, at least one sub-gate close to the continuously penetrating sub-gate is electrically connected to the adjacent connection portion through the first connection portion to form a first unipolar unit.

20. The photovoltaic module according to claim 18, characterized in that, In the sub-gate that is electrically connected to the edge interconnecting strip, at least one of the connecting portions is provided, and the edge interconnecting strip is electrically connected to the sub-gate through the connecting portion.

21. The photovoltaic module according to claim 20, characterized in that, The edge interconnect strip is in direct electrical contact with the connecting part.

22. The photovoltaic module according to claim 18, characterized in that, Along the extending direction of the first side, the spacing between the edge interconnect strip and the edge main grid is 2mm to 6mm.

23. The photovoltaic module according to claim 18, characterized in that, In the sub-gates that are insulated from the edge interconnection strip, a portion of the sub-gates are provided with the second notch, and another portion of the sub-gates are continuous.

24. The photovoltaic module according to claim 18, characterized in that, In the sub-gates that are insulated from the edge interconnecting strips, there are 1 to 10 continuously connected sub-gates.

25. The photovoltaic module according to claim 18, characterized in that, In the sub-gates that are insulated from the edge interconnecting strips, there are 1 to 3 continuously connected sub-gates.

26. The photovoltaic module according to claim 18, characterized in that, The width of the continuously connected sub-gate is greater than the width of the remaining sub-gates.

27. The photovoltaic module according to claim 26, characterized in that, The continuously connected sub-gate includes a bottom grid line and a top grid line arranged in layers. The bottom grid line is disposed on the surface of the battery body, and the top grid line is disposed on the side of the bottom grid line away from the battery body. The width of the top grid line is greater than the width of the bottom grid line or the other sub-gates.

28. The photovoltaic module according to claim 18, characterized in that, The electrode structure further includes a second connecting portion, which is disposed along the extending direction of the second side. The second connecting portion electrically connects the continuously penetrating sub-gate to the connecting portion of the same polarity to form a second unipolar unit.

29. The photovoltaic module according to claim 18, characterized in that, An interval region is provided between two adjacent sub-gates with opposite polarities; Along the thickness direction of the battery body, an insulating adhesive is provided between the edge interconnecting strip and the continuously extending sub-grid, and the insulating adhesive at least partially covers the spacing area.

30. The photovoltaic module according to claim 1, characterized in that, The electrode structure further includes multiple end main grids; along the extension direction of the second side, an end main grid of a predetermined length is provided near the first side of the battery body, and the end main grid is connected to at least two of the connecting portions; and / or, the electrode structure further includes multiple intermediate main grids; along the extension direction of the second side, the intermediate main grids are electrically connected to multiple of the connecting portions.

31. The photovoltaic module according to claim 30, characterized in that, The electrode structure includes a main grid, which includes the end main grid and / or the intermediate main grid, and insulating adhesive is provided at the intersection of the sub-grid with the interconnecting strip of opposite polarity or the main grid.

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