Solar cell, cell assembly and photovoltaic system

Abstract

The utility model is suitable for the technical field of solar cells, and provides a solar cell, a cell module and a photovoltaic system. The solar cell comprises a cell string, a plurality of fine grids, a bifurcated structure and a plurality of solder strips, a plurality of cell pieces are distributed along a first direction, a first fine grid and a second fine grid extend along the first direction, the bifurcated structure is arranged on the cell pieces, the first bifurcated structure is arranged at the end part of the first fine grid and / or the second bifurcated structure is arranged at the end part of the second fine grid, and the solder strips are arranged on the cell strings. The welding strips extend in the first direction and the second direction, the welding strips extend in the third direction and cover or partially cover the first fine grids and the second fine grids, at least one welding strip covers or partially covers the first fine grids and the first branch structures, at least one welding strip covers or partially covers the second fine grids and the second branch structures, and the included angle between the first direction and the third direction is acute. The welding strips and the fine grids are obliquely arranged at acute angles, so that the connection force between the welding strips and the fine grids is increased, and stable connection is ensured.

Description

Technical Field

[0001] The present application belongs to the technical field of solar cells, and in particular to a solar cell, a battery assembly and a photovoltaic system. Background Art

[0002] At present, solar cells are semiconductor devices that convert sunlight energy into electrical energy. Solar cells use the photovoltaic effect to excite electrons by absorbing photons, and then conduct these electrons to generate current through a built-in electric field. At this time, the grid line can collect and transmit current, thereby realizing the conversion of light energy into electrical energy. However, in the related art, stress concentration is prone to occur at the connection position between the grid line and the welding belt, and when the welding belt is set or laminated, the problem of disconnection between the welding belt and the grid line often occurs. Utility Model Content

[0003] The present application provides a solar cell, a battery assembly and a photovoltaic system, aiming to solve the problem of the welding ribbon and the grid line being separated during the use of the photovoltaic cell.

[0004] The present application provides a solar cell, the solar cell comprising a cell string, a plurality of fine grids, a bifurcated structure and a plurality of welding strips, the cell string comprising a plurality of cell sheets, the plurality of cell sheets being distributed and arranged along a first direction, the plurality of fine grids being arranged on the cell sheets, the fine grids comprising a plurality of first fine grids and a plurality of second fine grids, the first fine grids and the second fine grids extending along the first direction and alternately arranged along a second direction, the first fine grids and the second fine grids having opposite gate properties, the bifurcated structure being arranged on the cell sheets, the bifurcated structure comprising a first bifurcated structure and a second bifurcated structure, the first bifurcated structure being arranged at an end of the first fine grid and / or the second bifurcated structure being arranged at an end of the first fine grid At the end of the second fine grid, several welding strips are arranged on the battery cell, the welding strips extend along the third direction and are arranged at intervals along the second direction, the welding strips cover or partially cover the first fine grid and the second fine grid, and are conductively connected to the first fine grid and the second fine grid, there is at least one welding strip covering or partially covering the first fine grid and the first bifurcated structure, and is electrically connected to the first fine grid and the first bifurcated structure, there is at least one welding strip covering or partially covering the second fine grid and the second bifurcated structure, and is electrically connected to the second fine grid and the second bifurcated structure, wherein the angle between the first direction and the third direction is an acute angle.

[0005] In the solar cell according to the embodiment of the present application, the solar cell includes a battery string, a plurality of fine grids, a bifurcated structure, and a plurality of solder tapes. The battery string includes a plurality of battery cells, and the plurality of battery cells are arranged along a first direction. The plurality of fine grids are disposed on the battery cells. The fine grids include a plurality of first fine grids and a plurality of second fine grids. The first fine grids and the second fine grids extend along the first direction and are alternately arranged along a second direction. The first fine grids and the second fine grids have opposite polarities. The bifurcated structure is disposed on the battery cells. The bifurcated structure includes a first bifurcated structure and a second bifurcated structure. The first bifurcated structure is disposed at the end of the first fine grid and / or the second bifurcated structure is disposed at the end of the second fine grid. The plurality of solder tapes are disposed on the battery cells. The solder tapes extend along a third direction and are arranged at intervals along the second direction. The solder tapes cover or partially cover the first fine grids and the second fine grids and are electrically connected to the first fine grids and the second fine grids. There is at least one solder tape that covers or partially covers the first fine grid and the first bifurcated structure and is electrically connected to the first fine grid and the first bifurcated structure. There is at least one solder tape that covers or partially covers the second fine grid and the second bifurcated structure and is electrically connected to the second fine grid and the second bifurcated structure. Wherein, the included angle between the first direction and the third direction is acute. The solder tape and the fine grid can be arranged at an acute angle to increase the connection force between the solder tape and the fine grid and ensure stable connection. At the same time, setting the bifurcated structure can increase the contact area with the solder tape, thereby alleviating the problem of stress concentration to ensure stable connection between the solder tape and the battery cell.

[0006] Further, the battery cell includes a first battery cell and a second battery cell. The first fine grids of the first battery cell and the second fine grids of the second battery cell are arranged in one-to-one correspondence. The solder tapes include a first solder tape and a second solder tape. The first solder tape connects the first fine grids of the first battery cell and the first bifurcated structure and the second fine grids of the second battery cell and the second bifurcated structure. The second solder tape connects the first fine grids of the second battery cell and the first bifurcated structure and a connection member to be connected.

[0007] Further, the connection member to be connected is the second fine grid or the bus bar of another adjacent first battery cell.

[0008] Further, the bifurcated structure is in the shape of an open triangle, trapezoid, or rectangle.

[0009] Further, the bifurcated structure further includes a straight segment. The straight segment is connected to the end of the first fine grid and / or the second fine grid, and the straight segment extends along the first direction with the connected fine grid.

[0010] Further, the width D of the bifurcated structure along the second direction satisfies the following relational expression: 0 < D ≤ (P + 2S);

[0011] Wherein, P is the width of the solder strip along the second direction, and S is the spacing between two adjacent solder strips along the second direction.

[0012] Furthermore, the width D of the bifurcated structure along the second direction satisfies the following relationship: 0 < D ≤ (P + S);

[0013] Wherein, P is the width of the solder strip along the second direction, and S is the spacing between two adjacent solder strips along the second direction.

[0014] Furthermore, the included angle α between the first direction and the third direction satisfies the following relationship: 0 < tanα ≤ P / L;

[0015] Wherein, L is the total length of the outermost ends of the first cell and the last cell in the battery string along the first direction, and P is the width of the solder strip along the second direction.

[0016] Furthermore, the solar cell further includes a pad structure, and the pad structure is disposed within the bifurcated structure.

[0017] Furthermore, in the second direction, the center distances between two adjacent solder strips are equal;

[0018] The center distances between two adjacent grid lines are equal.

[0019] Furthermore, in the second direction, the width of the solder strip is greater than or equal to the width of the fine grid; or

[0020] In the second direction, the width of the solder strip is less than the width of the fine grid.

[0021] The battery module provided by the embodiment of the present application includes the solar cell according to any one of the above embodiments.

[0022] The photovoltaic system provided by the embodiment of the present application includes the battery module according to the above embodiment.

[0023] In the solar cell, cell module and photovoltaic system according to the embodiments of the present application, the solar cell includes a cell string, a plurality of fine grids, a bifurcated structure, and a plurality of solder tapes. The cell string includes a plurality of cells, which are arranged along a first direction. The plurality of fine grids are disposed on the cells. The fine grids include a plurality of first fine grids and a plurality of second fine grids. The first fine grids and the second fine grids extend along the first direction and are alternately arranged along a second direction. The first fine grids and the second fine grids have opposite polarities. The bifurcated structure is disposed on the cells and includes a first bifurcated structure and a second bifurcated structure. The first bifurcated structure is disposed at the end of the first fine grid and / or the second bifurcated structure is disposed at the end of the second fine grid. The plurality of solder tapes are disposed on the cells, extend along a third direction, and are spaced apart along the second direction. The solder tapes cover or partially cover the first fine grids and the second fine grids and are electrically connected to the first fine grids and the second fine grids. There is at least one solder tape that covers or partially covers the first fine grid and the first bifurcated structure and is electrically connected to the first fine grid and the first bifurcated structure. There is at least one solder tape that covers or partially covers the second fine grid and the second bifurcated structure and is electrically connected to the second fine grid and the second bifurcated structure. Wherein, the angle between the first direction and the third direction is acute. The solder tape and the fine grid can be arranged at an acute angle to increase the connection force between the solder tape and the fine grid and ensure stable connection. At the same time, the bifurcated structure is provided to increase the contact area with the solder tape, thereby alleviating the problem of stress concentration and ensuring stable connection between the solder tape and the cell. Description of the Drawings

[0024] Figure 1 is a partial plan view of a solar cell according to an embodiment of the present application;

[0025] Figure 2 is a partial plan view of a cell according to an embodiment of the present application;

[0026] Figure 3 is another partial plan view of a solar cell according to an embodiment of the present application;

[0027] Figure 4 is yet another partial plan view of a solar cell according to an embodiment of the present application;

[0028] Figure 5 is still another partial plan view of a solar cell according to an embodiment of the present application;

[0029] Figure 6 is a module structure diagram of a cell module according to an embodiment of the present application;

[0030] Figure 7 is a structure diagram of a photovoltaic system according to an embodiment of the present application.

[0031] Main Element Symbol Description:

[0032] Solar cell 100, cell 10, fine grid 11, first fine grid 111, second fine grid 112, first doping layer 123, second doping layer 124, bifurcation structure 13, first bifurcation structure 131, second bifurcation structure 132, straight segment 133, pad structure 14, first cell 101, second cell 102, solder ribbon 20, first solder ribbon 21, second solder ribbon 22, cell string 200, battery module 300, photovoltaic system 400. Detailed implementation manners

[0033] In order to make the objectives, technical solutions and advantages of the present application clearer and more understandable, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals represent the same or similar elements or elements with the same or similar functions from beginning to end. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present application, and should not be construed as a limitation to the present application. In addition, it should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0034] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the 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 therefore should not be construed as a limitation to the present application.

[0035] In addition, the terms "first", "second", "third", "fourth" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, the features defined with "first", "second", "third", "fourth" may explicitly or implicitly include one or more of the described features. In the description of the present application, the meaning of "a plurality" is two or more, unless otherwise specifically defined.

[0036] In the description of the present application, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected", "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection, an electrical connection or a communication with each other; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0037] In this application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the direct contact between the first and second features, or may also include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0038] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure of this application, the components and settings of specific examples are described hereinafter. Of course, they are merely examples and are not intended to limit this application. In addition, this application may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity, and in itself does not indicate the relationship between the various embodiments and / or settings discussed. In addition, this application provides examples of various specific processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use scenarios of other materials.

[0039] In the related art, a solar cell is a semiconductor device that directly converts the energy of sunlight into electrical energy. The solar cell utilizes the photovoltaic effect, absorbs photons to excite electrons, and exports these electrons through the built-in electric field to generate current. At this time, the fine grid can collect and transmit the current, thereby realizing the conversion of light energy into electrical energy. However, stress concentration is likely to occur at the connection position between the grid line and the solder ribbon. When setting the solder ribbon or during the lamination process, the problem that the solder ribbon is disconnected from the grid line often occurs. In the embodiment of this application, the solder ribbon and the fine grid are arranged at an acute angle to increase the connection force between the solder ribbon and the fine grid and ensure stable connection. At the same time, setting a bifurcated structure can further increase the contact area with the solder ribbon, thereby alleviating the problem of stress concentration to ensure stable connection between the solder ribbon and the battery chip.

[0040] Embodiment 1

[0041] Please refer to Figures 1 to 4, a solar cell 100 provided by the present application. The solar cell 100 includes a battery string 200, a plurality of fine grids 11, a bifurcation structure 13, and a plurality of solder tapes 20. The battery string 200 includes a plurality of battery cells 10, and the plurality of battery cells 10 are arranged along a first direction. The plurality of fine grids 11 are disposed on the battery cells 10. The fine grids 11 include a plurality of first fine grids 111 and a plurality of second fine grids 112. The first fine grids 111 and the second fine grids 112 extend along the first direction and are alternately arranged along a second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is disposed on the battery cells 10. The bifurcation structure 13 includes a first bifurcation structure 131 and a second bifurcation structure 132. The first bifurcation structure 131 is disposed at the end of the first fine grid 111 and / or the second bifurcation structure 132 is disposed at the end of the second fine grid 112. The plurality of solder tapes 20 are disposed on the battery cells 10. The solder tapes 20 extend along a third direction and are arranged at intervals along the second direction. The solder tapes 20 cover or partially cover the first fine grids 111 and the second fine grids 112 and are electrically connected to the first fine grids 111 and the second fine grids 112. There is at least one solder tape 20 that covers or partially covers the first fine grid 111 and the first bifurcation structure 131 and is electrically connected to the first fine grid 111 and the first bifurcation structure 131. There is at least one solder tape 20 that covers or partially covers the second fine grid 112 and the second bifurcation structure 132 and is electrically connected to the second fine grid 112 and the second bifurcation structure 132. Wherein, the included angle between the first direction and the third direction is an acute angle.

[0042] In the solar cell 100 according to the embodiment of the present application, the solar cell 100 includes a battery string 200, a plurality of fine grids 11, a bifurcation structure 13, and a plurality of solder tapes 20. The battery string 200 includes a plurality of battery chips 10, and the plurality of battery chips 10 are arranged along a first direction. The plurality of fine grids 11 are disposed on the battery chips 10. The fine grids 11 include a plurality of first fine grids 111 and a plurality of second fine grids 112. The first fine grids 111 and the second fine grids 112 extend along the first direction and are alternately arranged along a second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is disposed on the battery chips 10. The bifurcation structure 13 includes a first bifurcation structure 131 and a second bifurcation structure 132. The first bifurcation structure 131 is disposed at the end of the first fine grid 111 and / or the second bifurcation structure 132 is disposed at the end of the second fine grid 112. The plurality of solder tapes 20 are disposed on the battery chips 10. The solder tapes 20 extend along a third direction and are spaced apart along the second direction. The solder tapes 20 cover or partially cover the first fine grids 111 and the second fine grids 112 and are electrically connected to the first fine grids 111 and the second fine grids 112. There is at least one solder tape 20 that covers or partially covers the first fine grid 111 and the first bifurcation structure 131 and is electrically connected to the first fine grid 111 and the first bifurcation structure 131. There is at least one solder tape 20 that covers or partially covers the second fine grid 112 and the second bifurcation structure 132 and is electrically connected to the second fine grid 112 and the second bifurcation structure 132. Wherein, the included angle between the first direction and the third direction is an acute angle. Thus, by arranging the solder tape 20 to be inclined at an acute angle with the fine grid 11, the connection force between the solder tape 20 and the fine grid 11 is increased to ensure stable connection. At the same time, the arrangement of the bifurcation structure 13 can further increase the contact area with the solder tape 20, and thus the problem of stress concentration can be alleviated to ensure stable connection between the solder tape 20 and the battery chip 10.

[0043] In the embodiment of the present application, the type of the solar cell 100 is not limited to meet different requirements. For example, in this embodiment, the solar cell 100 may be a back-contact cell. At this time, the front surface of the battery chip 10 is used to receive light, and the back surface of the battery chip 10 includes a plurality of alternately arranged first doping layers 123 and second doping layers 124. Both the first doping layer 123 and the second doping layer 124 extend along the first direction. In some embodiments, the first doping layer 123 and the second doping layer 124 are alternately arranged along the second direction. At the same time, the first fine grids 111 and the second fine grids 112 extend along the first direction, the first fine grids 111 and the second fine grids 112 have opposite polarities, the first fine grids 111 and the second fine grids 112 are alternately arranged along the second direction, and the first fine grid 111 and the first doping layer 123 are electrically connected together, and the second fine grid 112 and the second doping layer 124 are electrically connected together. Please refer to Figure 1 and Figure 2, the first fine grid 111 and the second fine grid 112 are shielded by the solder ribbon 20. Therefore, the first fine grid 111 and the second fine grid 112 are represented by dotted lines below the solder ribbon 20.

[0044] Specifically, two first bifurcated structures 131 can be respectively arranged at both ends of the first fine grid 111, and two second bifurcated structures 132 can be respectively arranged at both ends of the second fine grid 112. In this way, when the solder ribbon 20 is arranged on the battery string 200, the solder ribbon 20 can be stably connected to the bifurcated structures 13 at both ends of the fine grid 11, so as to improve the connection stability between the solder ribbon 20 and the fine grid 11 and optimize the current collection and conduction efficiency. At least one solder ribbon 20 covers or partially covers the first fine grid 111 and the first bifurcated structure 131 and is electrically connected to the first fine grid 111 and the first bifurcated structure 131; similarly, at least one solder ribbon 20 covers or partially covers the second fine grid 112 and the second bifurcated structure 132 and is electrically connected to the second fine grid 112 and the second bifurcated structure 132. The included angle formed between the first direction and the third direction is an acute angle, and this design can enhance the connection force between the solder ribbon 20 and the fine grid 11 and ensure the stability of the electrical connection. Through the arrangement of the bifurcated structure 13, not only the contact area between the solder ribbon 20 and the fine grid 11 is increased, but also the stress concentration problem during the welding process can be effectively alleviated, thereby further ensuring the connection stability between the solder ribbon 20 and the battery cell 10. Such a design not only improves the current collection efficiency of the solar cell 100, but also enhances the durability and reliability of the overall structure.

[0045] Furthermore, the solder ribbon 20 can be arranged at an acute angle with the fine grid 11 to increase the contact area between the solder ribbon 20 and the fine grid 11, thereby increasing the electrical contact area between the solder ribbon 20 and the fine grid 11 and improving the conduction efficiency from the doped layer to the solder ribbon 20. At the same time, the inclined arrangement of the solder ribbon 20 can alleviate the stress concentration problem to ensure the stable connection between the solder ribbon 20 and the battery cell 10 and improve the connection stability between the solder ribbon 20 and the battery cell 10.

[0046] Even further, the bifurcated structure 13 can be made of the same material as the fine grid 11. At this time, the bifurcated structure 13 and the fine grid 11 can be formed on the battery cell 10 simultaneously. The bifurcated structure 13 can be bent and extended relative to the fine grid 11 towards the other two edges of the battery cell 10. The angle at which the bifurcated structure 13 is bent relative to the fine grid 11 is not limited here to meet different requirements. For example, the bifurcated structure 13 can have two bifurcated segments, and the angles at which the two bifurcated segments are bent relative to the first direction are 45° and -45°. At this time, the two bifurcated segments can be symmetrically arranged relative to the connected fine grid 11. Of course, in other embodiments, the two bifurcated segments can be asymmetrically arranged relative to the connected fine grid 11, which is not specifically limited here.

[0047] In the embodiment of the present application, the solder ribbon 20 is actively arranged at an acute angle to the doped layer, which can reduce the process difficulty of the battery module 300, reduce the alignment requirements during the welding process, improve the welding tolerance and precision, and reduce the manufacturing complexity. The inclined arrangement is more conducive to the operation of automated equipment, improves production efficiency, reduces manual intervention, and lowers production costs. The design of the solder ribbon 20 with an acute angle inclination helps to disperse mechanical stress, reduce stress concentration at the welding point, and improve the reliability and durability of the welding point.

[0048] In addition, in the embodiment of the present application, the shape of the cell 10 is not limited to meet different requirements. For example, the cell 10 can be a rectangular or square whole cell 10. Then, the square whole cell 10 is designed to correspond to a single rectangular cell 10 or a single cell 10 segment (two segments, three segments, etc.) after cutting. The front side of the cell 10 has no any fine grids 11 and electrode structures, and the positive and negative fine grids 11 are alternately distributed on the back side of the cell 10 in sequence. In addition, in the embodiment of the present application, the number of the first fine grid 111 and the second fine grid 112, as well as the size ranges of each and the spacing between adjacent fine grids 11 are not limited, as long as the fine grids 11 can be covered or partially covered by the solder ribbon 20 to meet different requirements.

[0049] Exemplarily, the first fine grid 111 can be the positive electrode, and the second fine grid 112 can be the negative electrode. Of course, in other embodiments, it can be the opposite, that is to say, the first fine grid 111 can be the negative electrode, and the second fine grid 112 can be the positive electrode, which is not specifically limited herein. The alternating distribution of the first fine grid 111 and the second fine grid 112 and their precise connection with the solder ribbon 20 enable the current to be collected and transmitted more effectively, reducing the electrical loss of the fine grids 11.

[0050] Specifically, the width of the solder ribbon 20 is less than the spacing between the first fine grid 111 and the second fine grid 112, ensuring that when arranging the solder ribbon 20, it will not simultaneously straddle and connect two adjacent fine grids 11. By controlling the width of the solder ribbon 20, it is possible to prevent a single solder ribbon 20 from simultaneously straddling two fine grids 11 of a single cell 10, thereby preventing short-circuit problems.

[0051] Furthermore, in the process of fabricating the battery string 200, the solder ribbon 20 can cover the fine grids 11 of multiple solar cells 10 on the same straight line along the third direction at one time, improving the welding efficiency, reducing the welding steps and time, and being suitable for large-scale production. The design that the solder ribbon 20 is attached to the fine grid 11 after being tilted at a certain angle facilitates the operation of automated equipment, improving the production precision and consistency. Then, the predetermined positions of different solar cells 10 are cut off by means of laser cutting or the like to form the battery string 200. In this way, the first doping layer 123 and the second doping layer 124 can conduct the current to the solder ribbon 20 through the first fine grid 111 and the second fine grid 112, so that the current can be further conducted to the bus bar through the solder ribbon 20.

[0052] In some embodiments, the distance between the first fine grid 111 and the second fine grid 112 is flexibly adjusted according to actual requirements. The first fine grid 111 and the second fine grid 112 can be arranged at equal intervals. The equal interval arrangement can ensure uniform current distribution and improve the overall efficiency of the battery module 300; the non-equal interval arrangement can optimize the current conduction path for specific application scenarios and reduce problems such as local overheating or excessive resistance. The combined arrangement of partial equal intervals and partial non-equal intervals can combine the advantages of both, be flexibly adjusted according to specific requirements, and optimize the performance of the battery module 300.

[0053] Furthermore, in some embodiments, the center distance between two adjacent fine grids 11 is equal; the center distance between two adjacent fine grids 11 is equal to the center distance between two adjacent solder ribbons 20. After the fine grids 11 are evenly distributed on the back of the solar cell 10, the solder ribbons 20 can also be evenly distributed on the back of the solar cell 10, and the center distance between adjacent solder ribbons 20 is equal to the center distance between adjacent fine grids 11, so that the solder ribbons 20 and the fine grids 11 can be accurately arranged in correspondence to ensure that each fine grid 11 can be effectively connected to the solder ribbon 20.

[0054] In addition, in the embodiments of the present application, "equal center distance" means that "the distance between the structural centers of two adjacent structures is equal to the distance between the structural centers of another two adjacent structures". The "equality" in the process of fabrication can allow the error ratio to be between 0.9 and 1.1. That is to say, when the rated center distance is 1, the maximum error distance can be 1.1 times the rated distance, and the minimum error distance can be 0.9 times the rated distance.

[0055] Further, in some embodiments, the plurality of solder tapes 20 are arranged in parallel; the first fine grid 111, the second fine grid 112, the first doping layer 123, and the second doping layer 124 are all arranged in parallel. In this way, the plurality of solder tapes 20 are arranged in parallel on the back surface of the cell 10 and are uniformly distributed in a direction perpendicular to the third direction, ensuring that the spacing between the solder tapes 20 is consistent and forming a regular layout. And it can make the solder tapes 20 can be correspondingly arranged with the fine grid 11 or the doping layer.

[0056] In the embodiments of the present application, the doping types of the first doping layer 123 and the second doping layer 124 are not limited. For example, the first doping layer 123 is a P-type doping layer and the second doping layer 124 is an N-type doping layer; it can also be that the first doping layer 123 is an N-type doping layer and the second doping layer 124 is a P-type doping layer, as long as the polarities of the two are opposite to meet different requirements. In some embodiments, the first doping layer 123 can be a P-type polysilicon layer, a P-type amorphous silicon layer, a P-type microcrystalline silicon layer, or an N-type polysilicon layer, an N-type amorphous silicon layer, an N-type microcrystalline silicon layer, which are not specifically limited herein. Similarly, the second doping layer 124 can be a P-type polysilicon layer, a P-type amorphous silicon layer, a P-type microcrystalline silicon layer, or an N-type polysilicon layer, an N-type amorphous silicon layer, an N-type microcrystalline silicon layer, which are not specifically limited herein, as long as the polarities of the two are opposite. When the first doping layer 123 is a P-type doping layer and the second doping layer 124 is an N-type doping layer, the first fine grid 111 on the first doping layer 123 is a P-type fine grid 11, and the second fine grid 112 on the second doping layer 124 is an N-type fine grid 11.

[0057] In some embodiments, P-type doping refers to doping group III elements, including elements such as boron, aluminum, gallium, indium, thallium, etc.; N-type doping refers to doping group V elements, including elements such as nitrogen, phosphorus, arsenic, antimony, bismuth, etc., which are not specifically limited herein. In addition, in some embodiments, the first doping layer 123 and the second doping layer 124 can also be composite doping. For example, N-type doping also includes a small amount of P-type doping elements. Among them, the content of N-type doping elements in the second doping layer 124 is higher than 20% of the content of P-type doping elements to ensure that the polarity is opposite to that of the first doping layer 123.

[0058] Embodiment Two

[0059] Please refer to Figure 1 and Figure 2, in some alternative embodiments, the solar cell 10 includes a first solar cell 101 and a second solar cell 102. The first fine grid 111 of the first solar cell 101 and the second fine grid 112 of the second solar cell 102 are arranged in one-to-one correspondence. The welding ribbon 20 includes a first welding ribbon 21 and a second welding ribbon 22. The first welding ribbon 21 connects the first fine grid 111 of the first solar cell 101 and the first bifurcation structure 131, and the second fine grid 112 of the second solar cell 102 and the second bifurcation structure 132. The second welding ribbon 22 connects the first fine grid 111 of the second solar cell 102 and the first bifurcation structure 131 to a component to be connected (not shown in the figure).

[0060] In this way, the first fine grid 111 of the first solar cell 101 and the second fine grid 112 of the second solar cell 102 are arranged in one-to-one correspondence along the same straight line; at the same time, the second fine grid 112 of the first solar cell 101 and the first fine grid 111 of the second solar cell 102 are arranged in one-to-one correspondence along the same straight line, so that the first welding ribbon 21 can connect the first solar cell 101 and the second solar cell 102 in series. The second welding ribbon 22 can connect the first fine grid 111 of the second solar cell 102 and other components to be connected together, and then multiple solar cells 10 can be connected in series to form a battery string 200.

[0061] Specifically, the first direction and the second direction can be perpendicular directions. At this time, the solar cell 10 can be rectangular to maximize the utilization of the area of the solar cell 10. The welding ribbon 20 is arranged on at least two solar cells 10 in the third direction, and electrically connects the first fine grid 111 of the solar cell 10 and the second fine grid 112 of the adjacent second solar cell 102 respectively. Among them, the first welding ribbon 21 connects the first fine grid 111 of the first solar cell 101 and the second fine grid 112 of the second solar cell 102, and the second welding ribbon 22 connects the first fine grid 111 of the second solar cell 102 and the second fine grid 112 of another first solar cell 101, and so on. The first welding ribbon 21 and the second welding ribbon 22 are alternately distributed in the second direction to connect the hetero-doped layers of adjacent solar cells 10 to form a battery string 200.

[0062] Furthermore, the included angle between the first direction and the third direction is an acute angle. By arranging the welding ribbon 20 to be inclined at an acute angle with respect to the doped layer, the contact area between the welding ribbon 20 and the solar cell 10 is significantly increased, thereby increasing the electrical contact area between the welding ribbon 20 and the doped layer and enhancing the conduction efficiency. At the same time, the inclined design of the welding ribbon 20 can effectively relieve the stress concentration problem, ensure the stability of the connection between the welding ribbon 20 and the solar cell 10, and reduce the connection failure caused by mechanical stress or temperature change. The firm connection between the welding ribbon 20 and the doped layer ensures the stable electrical connection between the solar cells 10, improving the reliability and service life.

[0063] Further, the two first bifurcated structures 131 can be respectively disposed at two ends of the first fine grid 111, and the two second bifurcated structures 132 can be respectively disposed at two ends of the second fine grid 112. In this way, when the solder strip 20 is disposed on the battery string 200, the solder strip 20 can be stably connected to the bifurcated structures 13 at two ends of the fine grid 11, so as to improve the connection stability between the solder strip 20 and the fine grid 11 and optimize the current collection and conduction efficiency.

[0064] It can be understood that the battery string 200 may include two battery cells 10 connected in series, or three battery cells 10 connected in series, or other more battery cells 10. Specifically, the number of battery cells 10 to be connected in series can be determined according to actual usage conditions. In addition, in the embodiments of the present application, the size and type of the battery cells 10 are not limited either. The specifications and sizes of adjacent battery cells 10 can be the same or different to meet different requirements.

[0065] In the embodiments of the present application, the specific arrangement manner of adjacent battery cells 10 is not limited to meet different requirements. In one embodiment, at least a part of the edges of two adjacent battery cells 10 are stacked together; in another embodiment, two adjacent battery cells 10 can be arranged at intervals. The distance between two adjacent battery cells 10 is within a suitable range, which can avoid the small operation space and large welding difficulty caused by too small a distance, and can also avoid wasting the component space and increasing the cost caused by too large a distance.

[0066] Exemplarily, in one example, the first fine grid 111 of the first battery cell 101 and the second fine grid 112 of the second battery cell 102 are in one-to-one correspondence along the same straight line. At this time, the first solder strip 21 is used to connect the first fine grid 111 of the first battery cell 101 and the second fine grid 112 of the second battery cell 102. At this time, the first bifurcated structure 131 can be disposed at one end of the first fine grid 111 away from the second battery cell 102, and the second bifurcated structure 132 can be disposed at one end of the second fine grid 112 away from the first battery cell 101. In this way, the first solder strip 21 can be electrically connected to the first fine grid 111 and the second fine grid 112, and is electrically connected to the first solder strip 21 through the two bifurcated structures 13. Furthermore, the first solder strip 21 can be stably electrically connected to the first fine grid of the first battery cell 101 and the second fine grid of the second battery cell 102.

[0067] In another example, the first solder strip 21 is used to connect the first fine grid 111 of the first battery cell 101 and the second fine grid 112 of the second battery cell 102. At this time, the first bifurcated structure 131 can be disposed at one end of the first fine grid 111 away from the second battery cell 102, and the second bifurcated structure 132 can be disposed at one end of the second fine grid 112 close to the first battery cell 101.

[0068] In yet another example, the first solder strip 21 is used to connect the first fine grid 111 of the first solar cell 101 and the second fine grid 112 of the second solar cell 102. At this time, the first bifurcated structure 131 can be disposed at one end of the first fine grid 111 close to the second solar cell 102, and the second bifurcated structure 132 can be disposed at one end of the second fine grid 112 far from the first solar cell 101.

[0069] In still another example, the first solder strip 21 is used to connect the first fine grid 111 of the first solar cell 101 and the second fine grid 112 of the second solar cell 102. At this time, the first bifurcated structure 131 can be disposed at one end of the first fine grid 111 close to the second solar cell 102, and the second bifurcated structure 132 can be disposed at one end of the second fine grid 112 close to the first solar cell 101.

[0070] It can be understood that the "first" and "second" in the first solar cell 101 and the second solar cell 102 are relative concepts, indicating that the two solar cells 100 are different. For example, in Figure 1 the example, the labeled solar cell 10 on the left is the first solar cell 101, and the solar cell 10 on the right is the second solar cell 102.

[0071] In some alternative embodiments, the solder strip 20 is in a long strip shape, and the width of the solder strip 20 is less than the spacing between the first fine grid 111 and the second fine grid 112. In this way, when the solder strip 20 is disposed on the solar cell 10, the problem of short circuit caused by one solder strip 20 simultaneously straddling two fine grids 11 of one solar cell 10 is avoided.

[0072] Embodiment III

[0073] Please refer to Figure 1 and Figure 2 . In some alternative embodiments, the component to be connected is the second fine grid 112 or the bus bar of another adjacent first solar cell 101.

[0074] In this way, the second solar cell 102 and another adjacent first solar cell 101 can be connected together by the second solder strip 22, or the second solar cell 102 and the adjacent bus bar can be connected together by the second solder strip 22, thereby forming a battery string 200.

[0075] Exemplarily, the component to be connected may be the second fine grid 112 of another adjacent first solar cell 101. During the process preparation, a solder strip 20 may be disposed on the fine grids 11 in the same straight line of multiple solar cells 10 simultaneously, and then may be disconnected at a predetermined position to ensure that the solder strip 20 can connect the first fine grid 111 and the second fine grid 112 of adjacent solar cells 10. For example, the first solder strip 21 may connect the first fine grid 111 of the first solar cell 10 and the second fine grid 112 of the second solar cell 10, and then be disconnected at one end of the second fine grid 112 of the second solar cell 10 away from the first solar cell 10. Similarly, the second solder strip 22 may connect the first fine grid 111 of the second solar cell 10 and the second fine grid 112 of another first solar cell 10, and then be disconnected at one end of the second fine grid 112 of the another first solar cell 10 away from the second solar cell 10. By analogy, a continuous battery string 200 may be formed.

[0076] In another example, the component to be connected may be a busbar structure (not shown in the figure). The busbar structure may connect the solder strips 20 of the same polarity to form a loop with the battery string 200 to export the current. The second solder strip 22 at the end of the battery string 200 may connect only the fine grid 11 on one solar cell 10 and extend relative to the solar cell 10 to connect the component to be connected such as the busbar structure. In the embodiments of the present application, the form of the busbar structure is not limited to meet different requirements. For example, the busbar structure may be a conductive material such as a wire, a busbar, or a conductive tape.

[0077] Embodiment 4

[0078] Please refer to Figure 1 、 Figure 2 and Figure 3 In some alternative embodiments, the bifurcation structure 13 is in the shape of an open triangle, trapezoid, or rectangle.

[0079] In this way, the bifurcation structure 13 may be any one of an open triangle, trapezoid, and rectangle, or may be a mixture of multiple figures to meet different connection requirements.

[0080] Specifically, by flexibly using these geometric shapes, it is possible to better adapt to different connection requirements and improve the overall performance of the solar cell 100. In this way, not only the connection stability of the solar cell 100 is improved, but also more choices are provided for the manufacturing process, further enhancing the adaptability and reliability of the product.

[0081] Embodiment 5

[0082] Please refer to Figures 3 to 5In some optional embodiments, the bifurcated structure 13 further includes a straight line segment 133, the straight line segment 133 is connected to the end of the first fine gate 111 and / or the second fine gate 112, and the straight line segment 133 and the connected fine gate 11 extend along the first direction.

[0083] In this way, the straight segment 133 can assist the bifurcated segment in connecting the welding ribbon and simplify the manufacturing process.

[0084] Embodiment 6

[0085] See also Figures 3 to 5 In some optional embodiments, the width D of the bifurcated structure 13 along the second direction satisfies the following relationship: 0<D≤(P+2S);

[0086] Wherein, P is the width of the soldering strip 20 along the second direction, and S is the interval between two adjacent soldering strips 20 along the second direction.

[0087] Thus, in such an embodiment, the bifurcated structures 13 may be arranged at intervals along the second direction at the ends of the first fine grid 111 or the second fine grid 112, that is, on a battery cell 10, the first bifurcated structure 131 may be arranged only on the first fine grid 111, and the bifurcated structure 13 may not be arranged on the second fine grid 112; or, on a battery cell 10, the second bifurcated structure 132 may be arranged only on the second fine grid 112, and the bifurcated structure 13 may not be arranged on the first fine grid 111. In this way, the material usage of the bifurcated structure 13 can be reduced while ensuring stable connection.

[0088] Exemplarily, a first bifurcated structure 131 may be provided on the first fine grid 111 of the first battery cell 101, and a first bifurcated structure 131 may be provided on the first fine grid 111 of the adjacent second battery cell 102. Thus, when the first welding strip 21 and the second welding strip 22 are alternately provided and connected to the battery cell 10, it can be ensured that at least one bifurcated structure 13 is connected to the welding strip 20, thereby ensuring that all battery cells 10 of the entire battery string 200 are stably connected to the welding strip 20.

[0089] In one example, the first fine grid 111 on the battery cell 10 is provided with the first bifurcated structure 131, and the second fine grid 112 is not provided with the bifurcated structure 13. In another example, the second bifurcated structure 132 is provided on the second fine grid 112 on the battery cell 10, and the first bifurcated structure 13 is not provided on the first fine grid 111. The width D of the bifurcated structure 13 along the second direction satisfies the following relationship: 0<D≤(P+2S).

[0090] Embodiment 7

[0091] See also Figures 3 to 5, in some alternative embodiments, the width D of the bifurcation structure 13 in the second direction satisfies the following relationship: 0 < D ≤ (P + S);

[0092] wherein, P is the width of the solder strip 20 in the second direction, and S is the spacing between two adjacent solder strips 20 in the second direction.

[0093] In this way, in such an embodiment, the bifurcation structure 13 needs to be disposed at the end of the first fine grid 111 and the end of the second fine grid 112 at the same time, so as to ensure the stable connection between each solder strip 20 and the fine grid 11.

[0094] Specifically, in such an embodiment, the solder strip 20 can cover or partially cover the bifurcation structure 13, so as to ensure that within the limited width range, the solder strip 20 can be in contact connection with at least a part of the area of the bifurcation structure 13, and ensure the stable electrical connection between the solder strip 20 and the fine grid 11.

[0095] In one example, a first bifurcation structure 131 is disposed on the first fine grid 111 of the battery cell 10, and a second bifurcation structure 132 is disposed on the second fine grid 112 at the same time. So that the width D of the bifurcation structure 13 in the second direction satisfies the following relationship: 0 < D ≤ (P + S).

[0096] Embodiment Eight

[0097] Please refer to Figures 1 to 3 , in some alternative embodiments, the included angle α between the first direction and the third direction satisfies the following relationship: 0 < tanα ≤ P / L;

[0098] wherein, L is the total length of the outermost ends of the first battery cell 10 and the last battery cell 10 in the battery string 200 in the first direction, and P is the width of the solder strip 20 in the second direction.

[0099] In this way, the inclination angle of the solder strip 20 can be obtained according to the length of the battery string 200, and the angle can be adjusted for different lengths and different types of battery strings 200, so that one solder strip 20 can first completely cover the doping layers on the same straight line of multiple battery cells 10. In this way, it is convenient for the process preparation. After the solder strip 20 is connected in series with multiple battery cells 10, laser selective shearing is performed to form battery strings 200 in pairs. This method can effectively ensure the uniform coverage of the solder strip 20 in the entire battery string 200, and at the same time provides convenience for subsequent processing and assembly of the battery cells 10. By optimizing the angle and coverage mode of the solder strip 20, the production efficiency can be improved, and the electrical performance and manufacturing quality of the battery cells 10 can be ensured.

[0100] Specifically, the inclination angle α of the solder strip 20 can be determined according to the total length L of the battery string 200. In this way, for battery strings 200 of different lengths and types, the angle can be adjusted so that a solder strip 20 can completely cover the doped layers on the same straight line of multiple solar cells 10. This design not only improves the covering efficiency of the solder strip 20, but also simplifies the process preparation process.

[0101] Furthermore, according to the length of the battery string 200 and the spacing width between the fine grids 11, the inclination angle of the solder strip 20 is flexibly adjusted to meet the specific requirements of different battery strings 200, ensuring that the solder strip 20 can completely cover the fine grids 11. Then, by accurately calculating the included angle α, the solder strip 20 can extend in a straight line when covering the doped layer, improving the welding efficiency and consistency. One solder strip can completely cover the fine grids 11 of multiple solar cells 10 on the production line, simplifying the welding process, reducing the welding steps, and improving the production efficiency. After the solder strip 20 connects multiple solar cells 10 in series, the battery string 200 is formed into groups of two by laser selective shearing. This method is efficient and accurate, reducing the complexity in the production process.

[0102] Exemplarily, the battery string 200 can be composed of 9 solar cells 10 evenly distributed in the first direction, and L is the distance between the outermost ends of the 9 solar cells 10. According to this length and the width of the doped layer in the second direction, the inclination angle α is calculated so that the solder strip 20 can be inclined at an angle of α.

[0103] In the embodiment of the present application, the included angle range between the first direction and the third direction is not limited to meet different requirements. In this way, it can be adjusted according to the length of different battery strings 200 and the width of the doped layer in the second direction.

[0104] In the embodiment of the present application, the center distance between two adjacent solder strips 20 is not limited to meet different requirements. For example, the center distance between two adjacent solder strips 20 can be greater than or equal to 100 μm, and preferably, the center distance between two adjacent solder strips 20 can be 300 μm.

[0105] Embodiment Nine

[0106] Please refer to Figure 1 and Figure 5 , in some alternative embodiments, the solar cell 100 further includes a pad structure 14, and the pad structure 14 is disposed within the bifurcated structure 13.

[0107] In this way, the pad structure 14 can assist the connection between the bifurcated structure 13 and the solder strip 20, ensuring a tighter connection between the end of the fine grid 11 and the solder strip 20.

[0108] Specifically, the pad structure 14, the straight segment 133, and the bifurcated structure 13 can be used in combination. For example, one end of the fine grid 11 is provided with the bifurcated structure 13 and the straight segment 133, and the other end can be provided with the pad structure 14; alternatively, the pad structure 14 can be provided for one grid line 11, and the bifurcated structure 13 and the straight segment 133 can be provided for another grid line, and the specific details are not limited herein.

[0109] Embodiment Ten

[0110] Please refer to Figures 1 to 3 , in some alternative embodiments, in the second direction, the width of the solder strip 20 is greater than or equal to the width of the fine grid 11; or

[0111] in the second direction, the width of the solder strip 20 is less than the width of the fine grid 11.

[0112] In this way, the width of the solder strip 20 can be larger than that of the fine grid 11 or smaller than that of the fine grid 11, and can be adjusted by itself to meet different requirements.

[0113] Specifically, when the width of the solder strip 20 is greater than or equal to the width of the fine grid 11, it can ensure that the solder strip 20 completely covers the width of the fine grid 11, providing a larger contact area, thereby enhancing the electrical connection between the solder strip 20 and the fine grid 11. This setting helps to improve the connection strength and stability of the solder strip 20 and ensure efficient current conduction. When the width of the solder strip 20 is less than the width of the fine grid 11, the width of the solder strip 20 is smaller, which can reduce the use of materials while still achieving effective current conduction. This flexible width adjustment ability enables the solder strip 20 to meet the design and manufacturing requirements of different solar cells 10. Whether the width of the solder strip 20 is selected to be greater or less than the width of the fine grid 11, it can optimize the production cost and process while ensuring electrical performance.

[0114] Embodiment Eleven

[0115] Please refer to Figure 6 , the battery module 300 provided by the implementation manner of the present application includes the solar cell 100 of any one of the above implementation manners.

[0116] In the solar cell 100 and the battery module 300 according to the embodiments of the present application, the solar cell 100 includes a battery string 200, a plurality of fine grids 11, a bifurcated structure 13, and a plurality of solder tapes 20. The battery string 200 includes a plurality of battery chips 10, and the plurality of battery chips 10 are arranged along a first direction. The plurality of fine grids 11 are disposed on the battery chips 10. The fine grids 11 include a plurality of first fine grids 111 and a plurality of second fine grids 112. The first fine grids 111 and the second fine grids 112 extend along the first direction and are alternately arranged along a second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcated structure 13 is disposed on the battery chips 10. The bifurcated structure 13 includes a first bifurcated structure 131 and a second bifurcated structure 132. The first bifurcated structure 131 is disposed at the end of the first fine grid 111 and / or the second bifurcated structure 132 is disposed at the end of the second fine grid 112. The plurality of solder tapes 20 are disposed on the battery chips 10. The solder tapes 20 extend along a third direction and are arranged at intervals along the second direction. The solder tapes 20 cover or partially cover the first fine grids 111 and the second fine grids 112 and are electrically connected to the first fine grids 111 and the second fine grids 112. There is at least one solder tape 20 that covers or partially covers the first fine grid 111 and the first bifurcated structure 131 and is electrically connected to the first fine grid 111 and the first bifurcated structure 131. There is at least one solder tape 20 that covers or partially covers the second fine grid 112 and the second bifurcated structure 132 and is electrically connected to the second fine grid 112 and the second bifurcated structure 132. Wherein, the included angle between the first direction and the third direction is an acute angle. Thus, by arranging the solder tape 20 to be inclined at an acute angle with the fine grid 11, the connection force between the solder tape 20 and the fine grid 11 is increased to ensure stable connection. At the same time, the bifurcated structure 13 is provided to further increase the contact area with the solder tape 20, thereby alleviating the problem of stress concentration to ensure stable connection between the solder tape 20 and the battery chip 10.

[0117] It can be understood that in such an embodiment, the battery module 300 may further include a frame, a backsheet, a photovoltaic glass, and an encapsulant film. The encapsulant film may be filled between the front and back surfaces of the battery chip 10, the photovoltaic glass, adjacent battery chips 10, etc. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulant film may be an EVA encapsulant film or a POE encapsulant film, which can be specifically selected according to actual situations and is not limited herein.

[0118] The photovoltaic glass may cover the encapsulant film on the front surface of the battery chip 10. The photovoltaic glass may be ultra-white glass, which has a high light transmittance, high transparency, and excellent physical, mechanical, and optical properties. For example, the light transmittance of the ultra-white glass can reach more than 92%, and it can protect the battery chip 10 without significantly affecting the efficiency of the battery chip 10. At the same time, the encapsulant film can bond the photovoltaic glass and the battery chip 10 together, and the presence of the encapsulant film can seal and insulate the battery chip 10 and prevent water and moisture.

[0119] The backsheet can be attached to the adhesive film on the back of the solar cell 10. The backsheet can protect and support the solar cell 10, and has reliable insulation, water resistance and aging resistance. There are multiple choices for the backsheet, which can usually be tempered glass, plexiglass, aluminum alloy TPT composite film, etc., and its specific settings can be determined according to specific situations and are not limited here. The whole composed of the backsheet, the solar cell 10, the adhesive film and the photovoltaic glass can be arranged on the frame. The frame serves as the main external support structure of the entire battery module 300, and can stably support and install the battery module 300. For example, the battery module 300 can be installed at the required installation position through the frame.

[0120] Example Twelve

[0121] Please refer to Figure 7 , the photovoltaic system 400 provided by the implementation mode of this application includes the battery module 300 of the above implementation mode.

[0122] In the solar cell 100, the battery module 300 and the photovoltaic system 400 of the implementation mode of this application, the solar cell 100 includes a battery string 200, a plurality of fine grids 11, a bifurcation structure 13 and a plurality of solder tapes 20. The battery string 200 includes a plurality of solar cells 10, and the plurality of solar cells 10 are arranged along a first direction. A plurality of fine grids 11 are arranged on the solar cells 10. The fine grids 11 include a plurality of first fine grids 111 and a plurality of second fine grids 112. The first fine grids 111 and the second fine grids 112 extend along the first direction and are alternately arranged along a second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is arranged on the solar cells 10. The bifurcation structure 13 includes a first bifurcation structure 131 and a second bifurcation structure 132. The first bifurcation structure 131 is arranged at the end of the first fine grid 111 and / or the second bifurcation structure 132 is arranged at the end of the second fine grid 112. A plurality of solder tapes 20 are arranged on the solar cells 10. The solder tapes 20 extend along a third direction and are arranged at intervals along the second direction. The solder tapes 20 cover or partially cover the first fine grids 111 and the second fine grids 112 and are electrically connected to the first fine grids 111 and the second fine grids 112. There is at least one solder tape 20 that covers or partially covers the first fine grid 111 and the first bifurcation structure 131 and is electrically connected to the first fine grid 111 and the first bifurcation structure 131. There is at least one solder tape 20 that covers or partially covers the second fine grid 112 and the second bifurcation structure 132 and is electrically connected to the second fine grid 112 and the second bifurcation structure 132. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, by arranging the solder tape 20 to be inclined at an acute angle with the fine grid 11, the connection force between the solder tape 20 and the fine grid 11 is increased to ensure stable connection. At the same time, setting the bifurcation structure 13 can further increase the contact area with the solder tape 20, and thus can relieve the problem of stress concentration to ensure the stable connection between the solder tape 20 and the solar cell 10.

[0123] In this embodiment, the photovoltaic system 400 can be applied in a photovoltaic power station, such as a ground power station, a rooftop power station, a water surface power station, etc., and can also be applied to devices or apparatuses that use solar energy for power generation, such as a user solar power supply, a solar street lamp, a solar car, a solar building, and so on. Of course, it can be understood that the application scenarios of the photovoltaic system 400 are not limited to this, that is to say, the photovoltaic system 400 can be applied in all fields that require solar power generation. Taking the photovoltaic power generation system network as an example, the photovoltaic system 400 can include a photovoltaic array, a busbar box, and an inverter. The photovoltaic array can be an array combination of multiple battery modules 300. For example, multiple battery modules 300 can form multiple photovoltaic arrays. The photovoltaic arrays are connected to the busbar box, and the busbar box can collect the current generated by the photovoltaic arrays. After the collected current flows through the inverter and is converted into alternating current required by the mains power grid, it is connected to the mains network to achieve solar power supply.

[0124] In the description of this specification, the description with reference to terms such as "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0125] In addition, the above are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, and improvements made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A solar cell, characterized in that, Comprising: A battery string, including a plurality of battery cells, and the plurality of battery cells are arranged along a first direction; A plurality of fine grids disposed on the battery cells, the fine grids including a plurality of first fine grids and a plurality of second fine grids, the first fine grids and the second fine grids extending along the first direction and being alternately arranged along a second direction, and the first fine grids and the second fine grids having opposite polarities; A bifurcated structure disposed on the battery cells, the bifurcated structure including a first bifurcated structure and a second bifurcated structure, the first bifurcated structure being disposed at an end of the first fine grid and / or the second bifurcated structure being disposed at an end of the second fine grid; A plurality of solder tapes disposed on the battery cells, the solder tapes extending along a third direction and being spaced apart along the second direction, the solder tapes covering or partially covering the first fine grids and the second fine grids and being electrically connected to the first fine grids and the second fine grids; There is at least one solder tape that covers or partially covers the first fine grid and the first bifurcated structure and is electrically connected to the first fine grid and the first bifurcated structure, and there is at least one solder tape that covers or partially covers the second fine grid and the second bifurcated structure and is electrically connected to the second fine grid and the second bifurcated structure; Wherein, the included angle between the first direction and the third direction is an acute angle.

2. The solar cell according to claim 1, characterized in that, The battery cell includes a first battery cell and a second battery cell, the first fine grids of the first battery cell and the second fine grids of the second battery cell are arranged in one-to-one correspondence, the solder tapes include a first solder tape and a second solder tape, the first solder tape connects the first fine grid of the first battery cell and the first bifurcated structure and the second fine grid of the second battery cell and the second bifurcated structure, and the second solder tape connects the first fine grid of the second battery cell and the first bifurcated structure to a connection member.

3. The solar cell according to claim 2, characterized in that, The connection member is the second fine grid or a bus bar of another adjacent first battery cell.

4. The solar cell according to claim 1, characterized in that, The bifurcated structure is in the shape of an open triangle or trapezoid or rectangle.

5. The solar cell according to claim 1, characterized in that, The bifurcated structure further includes a straight segment, the straight segment being connected to an end of the first fine grid and / or the second fine grid, and the straight segment extending along the first direction with the connected fine grid.

6. The solar cell according to claim 1, characterized in that, The width D of the bifurcated structure along the second direction satisfies the following relationship: 0 < D ≤ (P + 2S); Wherein, P is the width of the solder tape along the second direction, and S is the spacing between two adjacent solder tapes along the second direction.

7. The solar cell according to claim 6, characterized in that, The width D of the bifurcated structure along the second direction satisfies the following relationship: 0 < D ≤ (P + S); Wherein, P is the width of the solder tape along the second direction, and S is the spacing between two adjacent solder tapes along the second direction.

8. The solar cell according to claim 1, wherein, The included angle α between the first direction and the third direction satisfies the following relationship: 0 < tanα ≤ P / L; Wherein, L is the total length along the first direction of the outermost ends of the first battery cell and the last battery cell in the battery string, and P is the width of the solder tape along the second direction.

9. The solar cell according to claim 1, characterized in that, The solar cell further includes a pad structure, and the pad structure is disposed within the bifurcated structure.

10. The solar cell according to claim 1, characterized in that, In the second direction, the center distances between two adjacent ones of the solder tapes are equal; The center distances between two adjacent grid lines are equal.

11. The solar cell according to claim 1, characterized in that, In the second direction, the width of the solder tape is greater than or equal to the width of the fine grid; or In the second direction, the width of the solder tape is less than the width of the fine grid.

12. A battery assembly, characterized in that, Comprising a solar cell according to any one of claims 1-11.

13. A photovoltaic system, characterized in that, Comprising a battery module according to claim 12.

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