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, a first bifurcated section is arranged at the end part of the first fine grid and / or a second bifurcated section is arranged at the end part of the second fine grid, and a second bifurcated section is arranged at the end part of the second fine grid. 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 sections, at least one welding strip covers or partially covers the second fine grids and the second branch sections, 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] This application belongs to the technical field of solar cells, and particularly relates to a solar cell, a battery module and a photovoltaic system. Background Art

[0002] At present, a solar cell is a semiconductor device that converts the energy of sunlight into electrical energy. The solar cell utilizes the photovoltaic effect to excite electrons by absorbing photons, and exports these electrons through a built-in electric field to generate current. At this time, the grid lines can collect and transmit the current, thereby realizing the conversion of light energy into electrical energy. However, in the related art, stress concentration is likely to occur at the connection position between the grid lines and the solder tapes. When setting the solder tapes or performing lamination processing, the problem that the solder tapes are disconnected from the grid lines often occurs. Summary of the Utility Model

[0003] This application provides a solar cell, a battery module and a photovoltaic system, aiming to solve the problem that the solder tapes are separated from the grid lines during the use of photovoltaic cells.

[0004] A solar cell provided by this application includes a battery string, a plurality of fine grid lines, a bifurcated structure and a plurality of solder tapes. The battery string includes a plurality of battery chips, and there is at least one first battery chip and one second battery chip among the plurality of battery chips. The first battery chip and the second battery chip are arranged along a first direction, and the first battery chip and the second battery chip are located at both ends of the battery string. The battery string includes a first edge and a second edge that are oppositely arranged along a second direction. A plurality of the fine grid lines are arranged on the battery chips. The fine grid lines include a plurality of first fine grid lines and a plurality of second fine grid lines. The first fine grid lines and the second fine grid lines extend along the first direction and are alternately arranged along the second direction. The first fine grid lines and the second fine grid lines have opposite polarities. The bifurcated structure is arranged on the battery chips. The bifurcated structure includes a first bifurcated segment and a second bifurcated segment. The first bifurcated segment is arranged at the end of the first fine grid line and / or the end of the second fine grid line of the first battery chip and inclines towards the direction close to the first edge. The second bifurcated segment is arranged at the end of the first fine grid line and / or the end of the second fine grid line of the second battery chip and inclines towards the direction close to the second edge. A plurality of the solder tapes are arranged on the battery chips. 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 grid lines and the second fine grid lines and are electrically connected to the first fine grid lines and the second fine grid lines. There is at least one solder tape that covers or partially covers the first bifurcated segment and is electrically connected to the first bifurcated segment. There is at least one solder tape that covers or partially covers the second bifurcated segment and is electrically connected to the second bifurcated segment. Wherein, the included 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 bifurcation structure, and a plurality of welding tapes. The battery string includes a plurality of battery chips. Among the plurality of battery chips, there is at least one first battery chip and one second battery chip. The first battery chip and the second battery chip are arranged along a first direction, and the first battery chip and the second battery chip are located at both ends of the battery string. The battery string includes a first edge and a second edge arranged opposite to each other along a second direction. A plurality of fine grids are arranged on the battery chips. 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 the second direction. The first fine grids and the second fine grids have opposite polarities. The bifurcation structure is arranged on the battery chips. The bifurcation structure includes a first bifurcation segment and a second bifurcation segment. The first bifurcation segment is arranged at the end of the first fine grid and / or the end of the second fine grid of the first battery chip and inclines towards the direction close to the first edge. The second bifurcation segment is arranged at the end of the first fine grid and / or the end of the second fine grid of the second battery chip and inclines towards the direction close to the second edge. A plurality of welding tapes are arranged on the battery chips. The welding tapes extend along a third direction and are arranged at intervals along the second direction. The welding 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 welding tape that covers or partially covers the first bifurcation segment and is electrically connected to the first bifurcation segment. There is at least one welding tape that covers or partially covers the second bifurcation segment and is electrically connected to the second bifurcation segment. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, the welding tape and the fine grid can be arranged at an acute angle to increase the connection force between the welding tape and the fine grid and ensure stable connection. At the same time, setting the bifurcation structure can increase the contact area with the welding tape, thereby alleviating the problem of stress concentration to ensure stable connection between the welding tape and the battery chip. The unilateral bifurcation structure can save fine grid materials and reduce costs on the premise of ensuring stable connection.

[0006] Further, the first fine grid of the battery chip and the second fine grid of the adjacent battery chip are arranged in one-to-one correspondence;

[0007] The welding tape includes a first welding tape and a second welding tape. The first welding tape connects the first fine grid and the first bifurcation segment of the first battery chip and the second fine grid and the second bifurcation segment of the second battery chip. The second welding tape connects the first fine grid and the second bifurcation segment of the second battery chip and the to-be-connected component.

[0008] Further, the to-be-connected component is the second fine grid or the bus bar of another adjacent battery chip.

[0009] Further, the bifurcation structure further includes a third bifurcation segment and a fourth bifurcation segment. The third bifurcation segment is arranged at the end of the first fine grid and / or the second fine grid of the first battery chip and inclines towards the direction close to the second edge;

[0010] The fourth forked segment is disposed at the end of the first fine grid and / or the second fine grid of the second solar cell and is inclined in a direction close to the first edge.

[0011] Furthermore, the forked structure further includes a straight segment, the straight segment is disposed at the end of the first fine grid and / or the second fine grid of the first solar cell, and the straight segment extends along the first direction with the connected fine grid; and / or

[0012] The straight segment is disposed at the end of the first fine grid and / or the second fine grid of the second solar cell, and the straight segment extends along the first direction with the connected fine grid.

[0013] Furthermore, the first fine grid and / or the second fine grid of the first solar cell connect at least one of the first forked segments and at least one of the third forked segments;

[0014] The first fine grid and / or the second fine grid of the second solar cell connect at least one of the second forked segments and at least one of the fourth forked segments.

[0015] Furthermore, in the second direction, the width of the first forked segment is greater than or equal to the width of the third forked segment;

[0016] In the second direction, the width of the second forked segment is greater than or equal to the width of the fourth forked segment.

[0017] Furthermore, the angle at which the first forked segment inclines towards the first edge relative to the connected fine grid is greater than the angle at which the third forked segment inclines towards the second edge relative to the connected fine grid; and / or

[0018] The angle at which the second forked segment inclines towards the second edge relative to the connected fine grid is greater than the angle at which the fourth forked segment inclines towards the first edge relative to the connected fine grid.

[0019] Furthermore, the number of the first forked segments connected to the end of the fine grid is more than the number of the third forked segments; and / or

[0020] The number of the second forked segments connected to the end of the fine grid is more than the number of the fourth forked segments.

[0021] Furthermore, the width D of the forked structure in the second direction satisfies the following relational expression: 0 < D ≤ (P + 2S) / 2;

[0022] wherein, P is the width of the solder strip in the second direction, and S is the spacing between two adjacent solder strips in the second direction.

[0023] Furthermore, the width D of the bifurcated structure in the second direction satisfies the following relational expression: 0 < D ≤ (P + S) / 2;

[0024] wherein, P is the width of the solder strip in the second direction, and S is the spacing between two adjacent solder strips in the second direction.

[0025] Furthermore, the included angle α between the first direction and the third direction satisfies the following relational expression: 0 < tanα ≤ P / L;

[0026] wherein, L is the total length of the outermost ends of the first cell and the last cell in the battery string in the first direction, and P is the width of the bifurcated structure in the second direction.

[0027] Furthermore, the solar cell further includes a pad structure, and the pad structure is disposed within the bifurcated structure.

[0028] Furthermore, in the second direction, the center distances between two adjacent solder strips are equal;

[0029] The center distances between two adjacent grid lines are equal.

[0030] Furthermore, in the second direction, the width of the solder strip is greater than or equal to the width of the fine grid; or

[0031] In the second direction, the width of the solder strip is less than the width of the fine grid.

[0032] Furthermore, the cell further includes a third cell, the third cell is disposed between the first cell and the second cell, and the first bifurcated segment is provided at one end of the first fine grid and / or the second fine grid of the third cell close to the first cell, and the second bifurcated segment is provided at one end of the first fine grid and / or the second fine grid of the third cell close to the second cell.

[0033] Furthermore, one end of the solder strip away from the second cell inclines towards the direction close to the first edge, and one end of the solder strip away from the first cell inclines towards the direction close to the second edge.

[0034] The battery module provided by the embodiment of the present application includes the solar cell described in any one of the above embodiments.

[0035] The photovoltaic system provided by the embodiment of the present application includes the battery module described in the above embodiment.

[0036] In the solar cell, battery module, and photovoltaic system according to the embodiments of the present application, the solar cell includes a battery string, a plurality of fine grids, a bifurcation structure, and a plurality of solder tapes. The battery string includes a plurality of cells. Among the plurality of cells, there is at least one first cell and one second cell. The first cell and the second cell are arranged along a first direction, and the first cell and the second cell are located at both ends of the battery string. The battery string includes a first edge and a second edge that are oppositely arranged along a second direction. A plurality of fine grids are arranged 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 the second direction. The first fine grids and the second fine grids have opposite polarities. The bifurcation structure is arranged on the cells. The bifurcation structure includes a first bifurcation segment and a second bifurcation segment. The first bifurcation segment is arranged at the end of the first fine grid and / or the end of the second fine grid of the first cell and inclines toward the direction close to the first edge. The second bifurcation segment is arranged at the end of the first fine grid and / or the end of the second fine grid of the second cell and inclines toward the direction close to the second edge. A plurality of solder tapes are arranged on the 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 bifurcation segment and is electrically connected to the first bifurcation segment. There is at least one solder tape that covers or partially covers the second bifurcation segment and is electrically connected to the second bifurcation segment. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, 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 bifurcation 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 cell. The unilateral bifurcation structure can save fine grid materials and reduce costs on the premise of ensuring stable connection. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 is a partial plan structure schematic diagram of a solar cell according to an embodiment of the present application;

[0038] Figure 2 is a partial plan structure schematic diagram of a battery string according to an embodiment of the present application;

[0039] Figure 3 is another partial plan structure schematic diagram of a battery string according to an embodiment of the present application;

[0040] Figure 4 is yet another partial plan structure schematic diagram of a battery string according to an embodiment of the present application;

[0041] Figure 5 is another partial plan structure schematic diagram of a solar cell according to an embodiment of the present application;

[0042] Figure 6It is a schematic diagram of another part of the planar structure of a solar cell according to an embodiment of the present application;

[0043] Figure 7 It is an embodiment of the present application Figure 6 The enlarged schematic diagram of A in;

[0044] Figure 8 It is an embodiment of the present application Figure 6 The enlarged schematic diagram of B in;

[0045] Figure 9 It is a schematic diagram of the module structure of a battery module according to an embodiment of the present application;

[0046] Figure 10 It is a schematic diagram of the structure of a photovoltaic system according to an embodiment of the present application.

[0047] Main element symbol description:

[0048] 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 segment 131, second bifurcation segment 132, third bifurcation segment 133, fourth bifurcation segment 134, straight segment 135, pad structure 14, first cell 101, second cell 102, third cell 103, solder ribbon 20, first solder ribbon 21, second solder ribbon 22, battery string 200, first edge 201, second edge 202, battery module 300, photovoltaic system 400. Detailed implementation manners

[0049] In order to make the objectives, technical solutions and advantages of the present application clearer, 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 indicate the same or similar elements or elements with the same or similar functions throughout. 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.

[0050] In the description of the present application, it should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and 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 operate in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0051] In addition, the terms "first", "second", "third", and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, features defined with "first", "second", "third", and "fourth" may explicitly or implicitly include one or more of the said features. In the description of this application, "a plurality of" means two or more unless otherwise specifically defined.

[0052] In the description of this application, it should be noted that unless otherwise clearly specified and defined, the terms "mounted", "connected", and "coupled" shall be construed broadly. 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 connection capable of mutual communication; it may be directly connected, or indirectly connected through an intermediate medium, and it may be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0053] In this application, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include the first and second features being in direct contact, or may include the first and second features not being in direct contact but being in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes the first feature being directly above and diagonally above the second feature, or merely indicating that the first feature has a higher level height than the second feature. The first feature being "under", "below" and "beneath" the second feature includes the first feature being directly below and diagonally below the second feature, or merely indicating that the first feature has a lower level height than the second feature.

[0054] 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 below. 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. This repetition is for the purpose of simplification and clarity and does not in itself 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 may be aware of the application of other processes and / or the use scenarios of other materials.

[0055] In the related art, a solar cell is a semiconductor device that directly converts the energy of sunlight 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 fine grid can collect and transmit current, thereby realizing the conversion of light energy into electrical energy. However, stress concentration is prone to occur at the connection position between the grid line and the welding strip, and when setting the welding strip or laminating, the problem of disconnection between the welding strip and the grid line often occurs. In the embodiment of the present application, the welding strip and the fine grid can be tilted at an acute angle to increase the connection force between the welding strip and the fine grid, thereby ensuring a stable connection. At the same time, setting a bifurcated structure can increase the contact area with the welding strip, thereby alleviating the problem of stress concentration, so as to ensure a stable connection between the welding strip and the battery cell. The unilateral bifurcated structure can save fine grid materials and reduce costs under the premise of ensuring a stable connection.

[0056] Embodiment 1

[0057] See also 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 chips 10. Among the plurality of battery chips 10, there is at least one first battery chip 101 and one second battery chip 102. The first battery chip 101 and the second battery chip 102 are arranged along a first direction, and the first battery chip 101 and the second battery chip 102 are located at both ends of the battery string 200. The battery string 200 includes a first edge 201 and a second edge 202 that are oppositely arranged along a second direction. A plurality of fine grids 11 are arranged on the battery chip 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 the second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is arranged on the battery chip 10. The bifurcation structure 13 includes a first bifurcation segment 131 and a second bifurcation segment 132. The first bifurcation segment 131 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the first battery chip 101 and is inclined in the direction close to the first edge 201. The second bifurcation segment 132 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the second battery chip 102 and is inclined in the direction close to the second edge 202. A plurality of solder tapes 20 are arranged on the battery chip 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 bifurcation segment 131 and is electrically connected to the first bifurcation segment 131. There is at least one solder tape 20 that covers or partially covers the second bifurcation segment 132 and is electrically connected to the second bifurcation segment 132. Among them, the included angle between the first direction and the third direction is an acute angle.

[0058] 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 bifurcated structure 13, and a plurality of solder tapes 20. The battery string 200 includes a plurality of battery cells 10. Among the plurality of battery cells 10, there is at least one first battery cell 101 and one second battery cell 102. The first battery cell 101 and the second battery cell 102 are arranged along a first direction, and the first battery cell 101 and the second battery cell 102 are located at both ends of the battery string 200. The battery string 200 includes a first edge 201 and a second edge 202 that are oppositely arranged along a second direction. A plurality of fine grids 11 are arranged on the battery cell 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 the second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcated structure 13 is arranged on the battery cell 10. The bifurcated structure 13 includes a first bifurcated segment 131 and a second bifurcated segment 132. The first bifurcated segment 131 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the first battery cell 101 and is inclined towards the direction close to the first edge 201. The second bifurcated segment 132 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the second battery cell 102 and is inclined towards the direction close to the second edge 202. A plurality of solder tapes 20 are arranged on the battery cell 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 bifurcated segment 131 and is electrically connected to the first bifurcated segment 131. There is at least one solder tape 20 that covers or partially covers the second bifurcated segment 132 and is electrically connected to the second bifurcated segment 132. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, the solder tape 20 and the fine grid 11 can be arranged at an acute angle to increase the connection force between the solder tape 20 and the fine grid 11 and ensure stable connection. At the same time, the arrangement of the bifurcated structure 13 can increase the contact area with the solder tape 20, thereby alleviating the problem of stress concentration to ensure the stable connection between the solder tape 20 and the battery cell 10. The bifurcated structure 13 on one side can save the material of the fine grid 11 and reduce the cost on the premise of ensuring stable connection.

[0059] In the embodiments 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 cell 10 is used to receive light, and the back surface of the cell 10 includes a plurality of alternately arranged first doping layers 123 and second doping layers 124, and 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 grid 111 and the second fine grid 112 extend along the first direction, the first fine grid 111 and the second fine grid 112 have opposite polarities, the first fine grid 111 and the second fine grid 112 are alternately arranged along the second direction, the first fine grid 111 is electrically connected to the first doping layer 123, and the second fine grid 112 is electrically connected to the second doping layer 124. Please refer to Figure 1 , 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 shown in dotted lines below the solder ribbon 20.

[0060] Specifically, two first bifurcated segments 131 can be respectively arranged at both ends of the first fine grid 111, and two second bifurcated segments 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 structure 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 segment 131 and is electrically connected to the first fine grid 111 and the first bifurcated segment 131; similarly, at least one solder ribbon 20 covers or partially covers the second fine grid 112 and the second bifurcated segment 132 and is electrically connected to the second fine grid 112 and the second bifurcated segment 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 setting 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 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.

[0061] Exemplarily, a plurality of first cells 101 can be arranged at the front end of the battery string 200, and a plurality of second cells 102 can be arranged at the rear end of the battery string 200. First bifurcated segments 131 are arranged at both ends of the fine grid 11 of the first cell 101, and second bifurcated segments 132 are arranged at both ends of the fine grid 11 of the second cell 102.

[0062] Please refer toFigure 1 , in some alternative embodiments, the solder ribbon 20 inclines towards the first edge 201 at one end away from the second cell 102, and the solder ribbon 20 inclines towards the second edge 202 at one end away from the first cell 101.

[0063] In this way, the solder ribbon 20 extends along the third direction, which is consistent with the inclination directions of the first bifurcated segment 131 of the first cell 101 and the second bifurcated segment 132 of the second cell 102, ensuring that the solder ribbon 20 covers the bifurcated structure 13 as much as possible and improving the connection stability between the solder ribbon 20 and the fine grid 11.

[0064] Furthermore, the solder ribbon 20 and the fine grid 11 can be arranged to be acutely inclined 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 relieve the problem of stress concentration, ensuring the stable connection between the solder ribbon 20 and the cell 10 and improving the connection stability between the solder ribbon 20 and the cell 10.

[0065] 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 cell 10 simultaneously. The bifurcated structure 13 can extend after inclining towards the other two edges of the cell 10 relative to the fine grid 11. The angle at which the bifurcated structure 13 inclines relative to the fine grid 11 is not limited herein to meet different requirements. For example, the bifurcated structure 13 can have two bifurcated segments, and the angles of the two bifurcated segments inclined 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 herein.

[0066] In the embodiments of the present application, actively arranging the solder ribbon 20 to be acutely inclined to the doped layer can reduce the process difficulty of the battery module 300, reduce the alignment requirements during the welding process, improve the welding error tolerance and accuracy, and reduce the manufacturing complexity. The inclined arrangement is more conducive to the operation of automated equipment, improves the production efficiency, reduces manual intervention, and reduces the production cost. The design of the acutely inclined solder ribbon 20 helps to disperse mechanical stress, reduce stress concentration at the welding point, and improve the reliability and durability of the welding point.

[0067] In addition, in the embodiments of the present application, the shape of the battery cell 10 is not limited to meet different requirements. For example, the battery cell 10 can be a rectangular or square whole battery cell 10. Then, the square whole battery cell 10 is designed to correspond to a single rectangular battery cell 10 or a single battery cell 10 segment (two segments, three segments, etc.) after cutting. The front side of the battery 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 battery cell 10 in sequence. In addition, in the embodiments of the present application, the number of the first fine grid 111 and the second fine grid 112, the size ranges of each, and the spacing between adjacent fine grids 11 are not limited either, as long as the fine grids 11 can be covered or partially covered by the welding tape 20 to meet different requirements.

[0068] 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 welding tape 20 enable the current to be collected and transmitted more effectively, reducing the electrical loss of the fine grids 11.

[0069] Specifically, the width of the welding tape 20 is less than the spacing between the first fine grid 111 and the second fine grid 112, ensuring that when arranging the welding tape 20, it will not straddle and connect two adjacent fine grids 11 at the same time. By controlling the width of the welding tape 20, it is avoided that one welding tape 20 straddles two fine grids 11 of a battery cell 10 at the same time, thereby preventing the short - circuit problem.

[0070] Furthermore, in the process preparation of the battery string 200, the welding tape 20 can cover the fine grids 11 of multiple battery 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 welding tape 20 is attached to the fine grid 11 after being inclined at a certain angle is convenient for the operation of automated equipment, improving the production precision and consistency. Then, different battery cells 10 are cut off at the predetermined positions 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 welding tape 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 welding tape 20.

[0071] In some embodiments, the spacing 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 set with equal spacing, and the equal spacing setting can ensure uniform current distribution and improve the overall efficiency of the battery module 300; the non-equal spacing setting can optimize the current conduction path for specific application scenarios and reduce problems such as local overheating or excessive resistance. The combined setting of partial equal spacing and partial non-equal spacing can combine the advantages of both, be flexibly adjusted according to specific requirements, and optimize the performance of the battery module 300.

[0072] Furthermore, in some embodiments, the center distances between adjacent fine grids 11 are equal; the center distance between adjacent fine grids 11 is equal to the center distance between adjacent solder tapes 20. After the fine grids 11 are evenly distributed on the back surface of the battery chip 10, the solder tapes 20 can also be evenly distributed on the back surface of the battery chip 10, and the center distance between adjacent solder tapes 20 is equal to the center distance between adjacent fine grids 11, so that the solder tapes 20 and the fine grids 11 can be accurately correspondingly arranged to ensure that each fine grid 11 can effectively connect to the solder tape 20.

[0073] 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 preparation 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.

[0074] Furthermore, in some embodiments, the multiple 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 multiple solder tapes 20 are arranged in parallel on the back surface of the battery chip 10 and are evenly distributed along the 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 grids 11 or the doping layers.

[0075] 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 is also possible 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, and specific limitations are not made here. 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, and specific limitations are not made here, 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 corresponding 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.

[0076] 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., and specific limitations are not made here. In addition, in some embodiments, the first doping layer 123 and the second doping layer 124 can also be of 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 the opposite polarity to the first doping layer 123.

[0077] Embodiment 2

[0078] Please refer to Figure 1 and Figure 2 , in some alternative embodiments, the first fine grids 111 of the cell 10 and the second fine grids 112 of the adjacent cell 10 are arranged in one-to-one correspondence;

[0079] The solder ribbon 20 includes a first solder ribbon 21 and a second solder ribbon 22. The first solder ribbon 21 connects the first fine grid 111 of the first cell 101 and the first bifurcation section 131, and the second fine grid 112 of the second cell 102 and the second bifurcation section 132. The second solder ribbon 22 connects the first fine grid 111 of the second cell 102 and the second bifurcation section 132 to a connection member (not shown in the figure).

[0080] 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 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 in one-to-one correspondence along the same straight line, so that the first solder strip 21 can connect the first solar cell 101 and the second solar cell 102 in series. The second solder strip 22 can connect the first fine grid 111 of the second solar cell 102 and other components to be connected, and then the series connection of multiple solar cells 10 can be realized to form a battery string 200.

[0081] Specifically, the first direction and the second direction can be the vertical direction. At this time, the solar cell 10 can be rectangular to maximize the utilization of the area of the solar cell 10. The solder strip 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 solder strip 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 solder strip 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 solder strip 21 and the second solder strip 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.

[0082] Furthermore, the included angle between the first direction and the third direction is an acute angle. By arranging the solder strip 20 to be inclined at an acute angle with the doped layer, the contact area between the solder strip 20 and the solar cell 10 is significantly increased, thereby increasing the electrical contact area between the solder strip 20 and the doped layer and enhancing the conduction efficiency. At the same time, the inclined design of the solder strip 20 can effectively relieve the stress concentration problem, ensure the stability of the connection between the solder strip 20 and the solar cell 10, and reduce the connection failure caused by mechanical stress or temperature change. The firm connection between the solder strip 20 and the doped layer ensures the stable electrical connection between the solar cells 10, improving the reliability and service life.

[0083] Even further, two first bifurcated segments 131 can be respectively arranged at both ends of the fine grid 11 of the first solar cell 101, and two second bifurcated segments 132 can be respectively arranged at both ends of the fine grid 11 of the second solar cell 102. In this way, when the solder strip 20 is arranged on the battery string 200, the solder strip 20 can be stably connected to the bifurcated structure 13 at both 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.

[0084] 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 more battery cells 10. Specifically, the number of battery cells 10 to be connected in series can be determined according to actual usage. 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.

[0085] 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 component space and increasing costs caused by too large a distance.

[0086] In one embodiment, the battery string 200 has ten battery cells 10. The first five battery cells 10 along the first direction are all the first battery cells 101, and the last five battery cells 10 along the first direction are all the second battery cells 102. The grid lines of all the first battery cells 101 are provided with first bifurcation segments 131, and the grid lines of all the second battery cells 102 are provided with second bifurcation segments 132.

[0087] Exemplarily, in an example, the first battery cell 101 and the second battery cell 102 are arranged adjacent to each other, and the first fine grid 111 of the first battery cell 101 and the second fine grid 112 of the second battery cell 102 correspond one by one 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 bifurcation segment 131 can be arranged at one end of the first fine grid 111 away from the second battery cell 102, and the second bifurcation segment 132 can be arranged 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 bifurcation structures 13, so that the electrical connection between the first solder strip 21 and the first fine grid of the first battery cell 101 and the second fine grid of the second battery cell 102 can be stabilized.

[0088] In another example, the first battery cell 101 and the second battery cell 102 are arranged adjacent to each other, and 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 bifurcation segment 131 can be arranged at one end of the first fine grid 111 away from the second battery cell 102, and the second bifurcation segment 132 can be arranged at one end of the second fine grid 112 close to the first battery cell 101.

[0089] In yet another example, the first cell 101 and the second cell 102 are arranged adjacent to each other. The first solder ribbon 21 is used to connect the first fine grid 111 of the first cell 101 and the second fine grid 112 of the second cell 102. At this time, the first bifurcated segment 131 can be arranged at one end of the first fine grid 111 close to the second cell 102, and the second bifurcated segment 132 can be arranged at one end of the second fine grid 112 away from the first cell 101.

[0090] In still another example, the first cell 101 and the second cell 102 are arranged adjacent to each other. The first solder ribbon 21 is used to connect the first fine grid 111 of the first cell 101 and the second fine grid 112 of the second cell 102. At this time, the first bifurcated segment 131 can be arranged at one end of the first fine grid 111 close to the second cell 102, and the second bifurcated segment 132 can be arranged at one end of the second fine grid 112 close to the first cell 101.

[0091] It can be understood that the "first" and "second" in the first cell 101 and the second cell 102 are relative concepts, indicating that the two solar cells 100 are different. For example, in Figure 1 the example, the labeled cell 10 on the left is the first cell 101, and the cell 10 on the right is the second cell 102.

[0092] In another embodiment, the battery string 200 has ten cells 10. Along the first direction, only the first cell 10 is the first cell 101, and at the same time, the last cell 10 along the first direction is the second cell 102. The middle eight cells 10 are not provided with the bifurcated structure 13.

[0093] In another embodiment, the battery string 200 has nine cells 10. Along the first direction, the first four cells 10 are all the first cells 101, and along the first direction, the last four cells 10 are all the second cells 102. The grid lines of all the first cells 101 are provided with the first bifurcated segments 131, and the grid lines of all the second cells 102 are provided with the second bifurcated segments 132. Along the first direction, the fifth cell 10 is the third cell 103. The third cell 103 is provided with both the first bifurcated segment 131 and the second bifurcated segment 132. The fine grid of the third cell 103 is provided with the first bifurcated segment 131 at one end close to the first cell 101, and the fine grid of the third cell 103 is provided with the second bifurcated segment 132 at one end close to the second cell 102. In the embodiment of the present application, the numbers of the first cell 101, the second cell 102, and the third cell 103 are not limited to meet different requirements.

[0094] In some alternative embodiments, the solder ribbon 20 is in a long strip shape, and the width of the solder ribbon 20 is less than the spacing between the first fine grid 111 and the second fine grid 112. In this way, when the solder ribbon 20 is disposed on the cell 10, the problem of short circuit caused by one solder ribbon 20 straddling two fine grids 11 of one cell 10 at the same time is avoided.

[0095] Embodiment III

[0096] Please refer to Figures 1 to 3 , in some alternative embodiments, the component to be connected is the second fine grid 112 or the bus bar of another adjacent first cell 101.

[0097] In this way, the second cell 102 and another adjacent first cell 101 can be connected together by the second solder ribbon 22, or the second cell 102 and the adjacent bus bar can be connected together by the second solder ribbon 22, thereby forming a battery string 200.

[0098] Exemplarily, the component to be connected can be the second fine grid 112 of another adjacent first cell 101. During the process preparation, one solder ribbon 20 can be disposed on the fine grids 11 of the same straight line of multiple cells 10 at the same time, and then can be disconnected at a predetermined position to ensure that the solder ribbon 20 can connect the first fine grid 111 and the second fine grid 112 of adjacent cells 10. For example, the first solder ribbon 21 can connect the first fine grid 111 of the first cell 10 and the second fine grid 112 of the second cell 10, and then is disconnected at the end of the second fine grid 112 of the second cell 10 far from the first cell 10. Similarly, the second solder ribbon 22 can connect the first fine grid 111 of the second cell 10 and the second fine grid 112 of another first cell 10, and then is disconnected at the end of the second fine grid 112 of another first cell 10 far from the second cell 10. By analogy, a continuous battery string 200 can be formed.

[0099] In another example, the component to be connected can be a bus bar structure (not shown in the figure), and the bus bar structure can connect the solder ribbons 20 of the same polarity to form a loop with the battery string 200 to export the current. The second solder ribbon 22 at the end of the battery string 200 can only connect the fine grid 11 on one cell 10 and extend out relative to the cell 10 to connect the component to be connected such as the bus bar structure. In the embodiments of the present application, the form of the bus bar structure is not limited to meet different requirements. For example, the bus bar structure can be a conductive material such as a wire, a bus bar, or a conductive tape.

[0100] Embodiment IV

[0101] Please refer to Figures 3 to 5, in some alternative embodiments, the bifurcated structure 13 further includes a third bifurcated segment 133 and a fourth bifurcated segment 134. The third bifurcated segment 133 is disposed at the end of the first fine grid 111 and / or the second fine grid 112 of the first solar cell 101 and is inclined in a direction close to the second edge 202;

[0102] The fourth bifurcated segment 134 is disposed at the end of the first fine grid 111 and / or the second fine grid 112 of the second solar cell 102 and is inclined in a direction close to the first edge 201.

[0103] In this way, the third bifurcated segment 133 and the fourth bifurcated segment 134 can assist the fine grid 11 in connecting to the welding tape 20.

[0104] Specifically, the third bifurcated segment 133 and the first bifurcated segment 131 can be symmetrically or asymmetrically arranged relative to the fine grid 11; the fourth bifurcated segment 134 and the second bifurcated segment 132 can be symmetrically or asymmetrically arranged relative to the fine grid 11, and no specific limitation is made here.

[0105] In some alternative embodiments, the bifurcated structure 13 is in the shape of an open triangle or trapezoid or rectangle.

[0106] In this way, the bifurcated structure 13 can be any one of an open triangle, a trapezoid, and a rectangle, or a mixture of multiple figures to meet different connection requirements.

[0107] 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.

[0108] Embodiment Five

[0109] Please refer to Figures 3 to 5 , in some alternative embodiments, the bifurcated structure 13 further includes a straight segment 135. The straight segment 135 is connected to the end of the first fine grid 111 and / or the second fine grid 112 of the first solar cell 101, and the straight segment 135 extends along the first direction with the connected fine grid 11; and / or

[0110] The straight segment 135 is disposed at the end of the first fine grid 111 and / or the second fine grid 112 of the second solar cell 102, and the straight segment 135 extends along the first direction with the connected fine grid 11.

[0111] In this way, the straight segment 135 can assist the bifurcated segment in connecting the welding tape and can simplify the preparation process.

[0112] Embodiment Six

[0113] Please refer toFigures 6 to 8 , in some alternative embodiments, the first fine grid 111 and / or the second fine grid 112 of the first solar cell 101 connect at least one first bifurcated segment 131 and at least one third bifurcated segment 133;

[0114] The first fine grid 111 and / or the second fine grid 112 of the second solar cell 102 connect at least one second bifurcated segment 112 and at least one fourth bifurcated segment 134.

[0115] In this way, the number of the first bifurcated segment 131, the third bifurcated segment 133, the second bifurcated segment 112 and the fourth bifurcated segment 134 can be multiple, and the multiple bifurcated segments further increase the connection area with the welding strip 20, ensuring stable connection.

[0116] Embodiment Seven

[0117] Please refer to Figures 6 to 8 , in some alternative embodiments, in the second direction, the width of the first bifurcated segment 131 is greater than or equal to the width of the third bifurcated segment 133;

[0118] In the second direction, the width of the second bifurcated segment 132 is greater than or equal to the width of the fourth bifurcated segment 134.

[0119] Embodiment Eight

[0120] Please refer to Figures 6 to 8 , in some alternative embodiments, the angle at which the first bifurcated segment 131 inclines relative to the connected fine grid 11 towards the first edge 201 is greater than the angle at which the third bifurcated segment 133 inclines relative to the connected fine grid 11 towards the second edge 202; and / or

[0121] The angle at which the second bifurcated segment 132 inclines relative to the connected fine grid 11 towards the second edge 202 is greater than the angle at which the fourth bifurcated segment 134 inclines relative to the connected fine grid 11 towards the first edge 201.

[0122] In the embodiment of the present application, the angle at which the third bifurcated segment 133 inclines relative to the fine grid 11 towards the edge is smaller than the angle at which the first bifurcated segment 131 inclines relative to the fine grid 11 towards the edge. Similarly, the angle at which the fourth bifurcated segment 134 inclines relative to the fine grid 11 towards the edge is smaller than the angle at which the second bifurcated segment 132 inclines relative to the fine grid 11 towards the edge.

[0123] In one embodiment, the angle at which the first bifurcated segment 131 inclines relative to the connected fine grid 11 towards the first edge 201 is β1, and the angle at which the third bifurcated segment 133 inclines relative to the connected fine grid 11 towards the second edge 202 is β2. Since β1 is greater than β2, the width of the first bifurcated segment 131 along the second direction is greater than the width of the third bifurcated segment 133 along the second direction.

[0124] In another embodiment, the angle β3 of the second bifurcated segment 132 inclined relative to the connected thin grid 11 towards the second edge 202, and the angle β4 of the fourth bifurcated segment 134 inclined relative to the connected thin grid 11 towards the first edge 201, β3 is greater than β4. Therefore, the width of the second bifurcated segment 132 along the second direction is greater than the width of the fourth bifurcated segment 134 along the second direction.

[0125] Embodiment Nine

[0126] Please refer to Figures 6 to 8 , in some alternative embodiments, the number of the first bifurcated segments 131 connected to the end of the thin grid 11 is more than the number of the third bifurcated segments 133; and / or

[0127] the number of the second bifurcated segments 132 connected to the end of the thin grid 11 is more than the number of the fourth bifurcated segments 134.

[0128] Exemplarily, the number of the first bifurcated segments 131 can be three, and the angles of the three first bifurcated segments 131 inclined relative to the thin grid 11 are different. The number of the third bifurcated segments 133 can be two, and the angles of the two third bifurcated segments 133 inclined relative to the thin grid 11 are different. The number of the second bifurcated segments 132 can be three, and the angles of the three second bifurcated segments 132 inclined relative to the thin grid 11 are different. The number of the fourth bifurcated segments 134 can be two, and the angles of the two fourth bifurcated segments 134 inclined relative to the thin grid 11 are different.

[0129] Specifically, both the angle and the number of the first bifurcated segments 131 are greater than those of the third bifurcated segments 133, and both the angle and the number of the second bifurcated segments 132 are greater than those of the fourth bifurcated segments 134 to ensure a larger contact area with the welding tape 20.

[0130] Embodiment Ten

[0131] Please refer to Figures 1 to 3 and Figure 7 , in some alternative embodiments, the width D of the bifurcated structure 13 along the second direction satisfies the following relational expression: 0 < D ≤ (P + 2S) / 2;

[0132] wherein, P is the width of the welding tape 20 along the second direction, and S is the spacing between two adjacent welding tapes 20 along the second direction.

[0133] Thus, in such an embodiment, the bifurcated structure 13 can be arranged at intervals along the second direction at the end of the first fine grid 111 or the second fine grid 112. That is to say, on one first cell 101, the first bifurcated segment 131 can be arranged only on the first fine grid 111, and the bifurcated structure 13 is not arranged on the second fine grid 112; or, on one first cell 101, the second bifurcated segment 132 can be arranged only on the second fine grid 112, and the bifurcated structure 13 is not arranged on the first fine grid 111. In this way, while ensuring stable connection, the material usage of the bifurcated structure 13 can be reduced. The same applies to the second cell 102.

[0134] Exemplarily, the first bifurcated segment 131 can be arranged on the first fine grid 111 of the first cell 101, and at the same time, the first bifurcated segment 131 can be arranged on the first fine grid 111 of the adjacent second cell 102. In this way, when the first solder strip 21 and the second solder strip 22 are arranged alternately and connected to the cell 10, it can be ensured that at least one bifurcated structure 13 is connected to the solder strip 20, thereby ensuring stable connection between all the cells 10 of the entire cell string 200 and the solder strip 20.

[0135] In one example, the first bifurcated segment 131 is arranged on the first fine grid 111 of the cell 10, and the bifurcated structure 13 is not arranged on the second fine grid 112. In another example, the second bifurcated segment 132 is arranged on the second fine grid 112 of the cell 10, and the bifurcated structure 13 is not arranged on the first fine grid 111. So that the width D of the bifurcated structure 13 along the second direction satisfies the following relational expression: 0 < D ≤ (P + 2S) / 2.

[0136] Example XI

[0137] Please refer to Figures 1 to 3 and Figure 7 , in some alternative embodiments, the width D of the bifurcated structure 13 along the second direction satisfies the following relational expression: 0 < D ≤ (P + S) / 2;

[0138] wherein, P is the width of the solder strip 20 along the second direction, and S is the spacing between two adjacent solder strips 20 along the second direction.

[0139] Thus, in such an embodiment, the bifurcated structure 13 needs to be arranged at the ends of both the first fine grid 111 and the second fine grid 112 at the same time. In this way, the connection stability between each solder strip 20 and the fine grid 11 can be ensured.

[0140] Specifically, in such an embodiment, the solder strip 20 can cover or partially cover the bifurcated structure 13 to ensure that within the limited width range, the solder strip 20 can be in contact connection with at least a partial area of the bifurcated structure 13, ensuring stable electrical connection between the solder strip 20 and the fine grid 11.

[0141] In one example, a first bifurcation segment 131 is provided on the first fine grid 111 on the cell 10, and a second bifurcation segment 132 is provided 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 relational expression: 0 < D ≤ (P + S) / 2.

[0142] Example 12

[0143] Please refer to Figures 1 to 3 and Figure 7 , in some alternative embodiments, the included angle α between the first direction and the third direction satisfies the following relational expression: 0 < tanα ≤ P / L;

[0144] Wherein, L is the total length of the outermost ends of the first cell 10 and the last cell 10 in the battery string 200 in the first direction, and P is the width of the welding tape 20 in the second direction.

[0145] In this way, the inclination angle of the welding tape 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 a welding tape 20 can first completely cover the doping layers on the same straight line of multiple cells 10. In this way, the process preparation can be facilitated. After the welding tape 20 is connected in series with multiple cells 10, laser selective shearing is performed to form battery strings 200 in pairs. This method can effectively ensure the uniform coverage of the welding tape 20 in the entire battery string 200, and at the same time provides convenience for subsequent processing and assembly of the cells 10. By optimizing the angle and coverage mode of the welding tape 20, the production efficiency can be improved, and the electrical performance and manufacturing quality of the cells 10 can be ensured.

[0146] Specifically, the inclination angle α of the welding tape 20 can be determined according to the total length L of the battery string 200. In this way, for different lengths and types of battery strings 200, the angle can be adjusted, so that a welding tape 20 can completely cover the doping layers on the same straight line of multiple cells 10. This design not only improves the coverage efficiency of the welding tape 20, but also simplifies the process preparation process.

[0147] Furthermore, according to the length of the battery string 200 and the spacing width between the fine grids 11, the inclination angle of the welding tape 20 is flexibly adjusted to meet the specific requirements of different battery strings 200, ensuring that the welding tape 20 can completely cover the fine grids 11. Then, by accurately calculating the included angle α, the welding tape 20 can extend along a straight line when covering the doping layer, improving the welding efficiency and consistency. A welding tape can completely cover the fine grids 11 of multiple cells 10 on the production line, simplifying the welding process, reducing the welding steps, and improving the production efficiency. After the welding tape 20 is connected in series with multiple cells 10, laser selective shearing is performed to form battery strings 200 in pairs. This method is efficient and accurate, reducing the complexity in the production process.

[0148] Exemplarily, the battery string 200 may have 9 battery cells 10 evenly distributed in the first direction, and L is the distance between the outermost ends of the 9 battery cells 10. According to this length and the width of the doping layer in the second direction, the inclination angle α is calculated so that the solder ribbon 20 can be inclined at an angle of α.

[0149] In the embodiments 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 lengths of different battery strings 200 and the width of the doping layer in the second direction.

[0150] In the embodiments of the present application, the center distance between two adjacent solder ribbons 20 is not limited to meet different requirements. For example, the center distance between two adjacent solder ribbons 20 may be greater than or equal to 100 μm. Preferably, the center distance between two adjacent solder ribbons 20 may be 300 μm.

[0151] Example Thirteen

[0152] 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.

[0153] In this way, the pad structure 14 can assist in connecting the bifurcated structure 13 to the solder ribbon 20, ensuring a tighter connection between the end of the fine grid 11 and the solder ribbon 20.

[0154] Specifically, the pad structure 14, the straight segment 135, and the bifurcated structure 13 can be used in combination. For example, one end of the fine grid 11 is provided with a bifurcated structure 13 and a straight segment 135, and the other end can be provided with a pad structure 14; alternatively, a pad structure 14 can be provided for one grid line 11, and a bifurcated structure 13 and a straight segment 135 can be provided for another grid line, and the specific details are not limited herein.

[0155] Example Fourteen

[0156] Please refer to Figures 6 to 8 , in some alternative embodiments, in the second direction, the width of the solder ribbon 20 is greater than or equal to the width of the fine grid 11; or

[0157] in the second direction, the width of the solder ribbon 20 is less than the width of the fine grid 11.

[0158] In this way, the width of the solder ribbon 20 can be larger or smaller than that of the fine grid 11, and can be adjusted by itself to meet different requirements.

[0159] 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 and thus 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 smaller width of the solder strip 20 can reduce the material usage 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.

[0160] Example Fifteen

[0161] Please refer to Figures 4 to 6 , in some alternative embodiments, the solar cell 10 further includes a third solar cell 103 disposed between the first solar cell 101 and the second solar cell 102. A first bifurcated segment 131 is provided at one end of the first fine grid 111 and / or the second fine grid 112 of the third solar cell 103 close to the first solar cell 101, and a second bifurcated segment 132 is provided at one end of the first fine grid 111 and / or the second fine grid 112 of the third solar cell 103 close to the second solar cell 102.

[0162] In this way, a first bifurcated segment 131 is provided at one end of the first fine grid 111 and / or the second fine grid 112 of the third solar cell 103 close to the first solar cell 101, and a second bifurcated segment 132 is provided at one end of the first fine grid 111 and / or the second fine grid 112 of the third solar cell 103 close to the second solar cell 102. In this way, the coverage contact area of the solder strip 20 on the fine grid 11 can be increased.

[0163] Example Sixteen

[0164] Please refer to Figure 9 , the battery module 300 provided by the embodiment of the present application includes the solar cell 100 of any one of the above embodiments.

[0165] 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 bifurcation structure 13, and a plurality of solder tapes 20. The battery string 200 includes a plurality of battery chips 10. Among the plurality of battery chips 10, there is at least one first battery chip 101 and one second battery chip 102. The first battery chip 101 and the second battery chip 102 are arranged along a first direction, and the first battery chip 101 and the second battery chip 102 are located at both ends of the battery string 200. The battery string 200 includes a first edge 201 and a second edge 202 that are oppositely arranged along a second direction. A plurality of fine grids 11 are arranged on the battery chip 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 the second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is arranged on the battery chip 10. The bifurcation structure 13 includes a first bifurcation segment 131 and a second bifurcation segment 132. The first bifurcation segment 131 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the first battery chip 101 and is inclined in a direction close to the first edge 201. The second bifurcation segment 132 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the second battery chip 102 and is inclined in a direction close to the second edge 202. A plurality of solder tapes 20 are arranged on the battery chip 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 bifurcation segment 131 and is electrically connected to the first bifurcation segment 131. There is at least one solder tape 20 that covers or partially covers the second bifurcation segment 132 and is electrically connected to the second bifurcation segment 132. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, the solder tape 20 and the fine grid 11 can be arranged at an acute angle to increase the connection force between the solder tape 20 and the fine grid 11 and ensure stable connection. At the same time, setting the bifurcation structure 13 can increase the contact area with the solder tape 20, and thus can relieve the problem of stress concentration to ensure stable connection between the solder tape 20 and the battery chip 10. The unilateral bifurcation structure 13 can save the material of the fine grid 11 and reduce the cost on the premise of ensuring stable connection.

[0166] It can be understood that in such an embodiment, the battery module 300 may further include a frame, a backplane, a photovoltaic glass, and an encapsulant film. The encapsulant film can be filled between the front and back of the battery chip 10, between the photovoltaic glass, adjacent battery chips 10, etc. As a filler, it can be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulant film can adopt an EVA encapsulant film or a POE encapsulant film, and specific selection can be made according to actual situations, which is not limited herein.

[0167] The photovoltaic glass can be covered on the adhesive film on the front side of the battery cell 10. The photovoltaic glass can be ultra-white glass, which has 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 cell 10 without significantly affecting the efficiency of the battery cell 10. At the same time, the adhesive film can bond the photovoltaic glass and the battery cell 10 together, and the presence of the adhesive film can seal and insulate the battery cell 10 and prevent water and moisture.

[0168] The backsheet can be attached to the adhesive film on the back side of the battery cell 10. The backsheet can protect and support the battery 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 adhesive film, etc., and its specific settings can be determined according to specific circumstances and are not limited here. The overall structure composed of the backsheet, the battery cell 10, the adhesive film, and the photovoltaic glass can be arranged on the frame. The frame is 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 location through the frame.

[0169] Embodiment XVII

[0170] Please refer to Figure 10 , the photovoltaic system 400 provided by the embodiment of the present application includes the battery module 300 of the above embodiment.

[0171] In the solar cell 100, the battery module 300, and the photovoltaic system 400 according to the embodiments 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. Among the plurality of battery chips 10, there is at least one first battery chip 101 and one second battery chip 102. The first battery chip 101 and the second battery chip 102 are arranged along a first direction, and the first battery chip 101 and the second battery chip 102 are located at both ends of the battery string 200. The battery string 200 includes a first edge 201 and a second edge 202 that are oppositely arranged along a second direction. The plurality of fine grids 11 are arranged on the battery chip 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 the second direction. The first fine grids 111 and the second fine grids 112 have opposite polarities. The bifurcation structure 13 is arranged on the battery chip 10. The bifurcation structure 13 includes a first bifurcation segment 131 and a second bifurcation segment 132. The first bifurcation segment 131 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the first battery chip 101 and inclines toward the direction close to the first edge 201. The second bifurcation segment 132 is arranged at the end of the first fine grid 111 and / or the end of the second fine grid 112 of the second battery chip 102 and inclines toward the direction close to the second edge 202. The plurality of solder tapes 20 are arranged on the battery chip 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 bifurcation segment 131 and is electrically connected to the first bifurcation segment 131. There is at least one solder tape 20 that covers or partially covers the second bifurcation segment 132 and is electrically connected to the second bifurcation segment 132. Among them, the included angle between the first direction and the third direction is an acute angle. In this way, the solder tape 20 and the fine grid 11 are arranged at an acute angle to increase the connection force between the solder tape 20 and the fine grid 11 and ensure stable connection. At the same time, setting the bifurcation structure 13 can increase the contact area with the solder tape 20, and further alleviate the problem of stress concentration to ensure stable connection between the solder tape 20 and the battery chip 10. The unilateral bifurcation structure 13 can save the material of the fine grid 11 and reduce the cost on the premise of ensuring stable connection.

[0172] 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., or 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 vehicle, a solar building, and so on. Of course, it can be understood that the application scenarios of the photovoltaic system 400 are not limited thereto, 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 components 300. For example, multiple battery components 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. The collected current flows through the inverter and is converted into alternating current required by the commercial power grid and then connected to the commercial power grid to achieve solar power supply.

[0173] In the description of this specification, the descriptions with reference to the terms "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiments or examples are included in at least one embodiment or example of the present application. 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.

[0174] 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: include: A battery string, comprising a plurality of battery cells, wherein there is at least one first battery cell and one second battery cell among the plurality of battery cells, the first battery cell and the second battery cell are distributed along a first direction, and the first battery cell and the second battery cell are located at two ends of the battery string, and the battery string comprises a first edge and a second edge arranged opposite to each other along a second direction; A plurality of fine grids are arranged on the battery sheet, 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 the second direction, and the first fine grids and the second fine grids have opposite properties; a bifurcated structure disposed on the battery cell, the bifurcated structure comprising a first bifurcated segment and a second bifurcated segment, the first bifurcated segment being disposed at the first fine grid end and / or the second fine grid end of the first battery cell and being inclined toward the first edge, and the second bifurcated segment being disposed at the first fine grid end and / or the second fine grid end of the second battery cell and being inclined toward the second edge; A plurality of 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 bifurcated segment and being electrically connected to the first bifurcated segment, and there is at least one welding strip covering or partially covering the second bifurcated segment and being electrically connected to the second bifurcated segment; Wherein, the 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 first fine grid of the battery cell and the second fine grid of the adjacent battery cell are arranged in one-to-one correspondence; The welding strip includes a first welding strip and a second welding strip, the first welding strip connects the first fine grid and the first forked segment of the first battery cell and the second fine grid and the second forked segment of the second battery cell, and the second welding strip connects the first fine grid and the second forked segment of the second battery cell and the part to be connected.

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

4. The solar cell according to claim 1, characterized in that The bifurcated structure further includes a third bifurcated segment and a fourth bifurcated segment, wherein the third bifurcated segment is arranged at the end of the first fine grid and / or the second fine grid of the first battery cell and is inclined toward the direction close to the second edge; The fourth bifurcated segment is disposed at an end of the first fine grid and / or the second fine grid of the second battery cell and is inclined toward a direction close to the first edge.

5. The solar cell according to claim 1 or 4, characterized in that: The bifurcated structure further includes a straight line segment, which is arranged at an end of the first fine grid and / or the second fine grid of the first battery cell, and the straight line segment and the connected fine grid extend along the first direction; and / or The straight line segment is arranged at an end of the first fine grid and / or the second fine grid of the second battery cell, and the straight line segment and the connected fine grid extend along the first direction.

6. The solar cell according to claim 4, characterized in that: The first fine grid and / or the second fine grid of the first battery cell connect at least one of the first forked segments and at least one of the third forked segments; The first fine grid and / or the second fine grid of the second battery cell connects at least one of the second forked segments and at least one of the fourth forked segments.

7. The solar cell according to claim 6, characterized in that: In the second direction, the width of the first bifurcated segment is greater than or equal to the width of the third bifurcated segment; In the second direction, the width of the second bifurcated segment is greater than or equal to the width of the fourth bifurcated segment.

8. The solar cell according to claim 7, characterized in that: The angle at which the first bifurcated segment is inclined toward the first edge relative to the connected fine grid is greater than the angle at which the third bifurcated segment is inclined toward the second edge relative to the connected fine grid; and / or The angle at which the second bifurcated segment is inclined toward the second edge relative to the connected fine grid is greater than the angle at which the fourth bifurcated segment is inclined toward the first edge relative to the connected fine grid.

9. The solar cell according to claim 6, characterized in that: The number of the first bifurcated segments connected to the ends of the fine grid is greater than the number of the third bifurcated segments; and / or The number of the second branched segments connected to the ends of the fine grid is greater than the number of the fourth branched segments.

10. 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) / 2; Wherein, P is the width of the welding strip along the second direction, and S is the distance between two adjacent welding strips along the second direction.

11. The solar cell according to claim 10, characterized in that The width D of the bifurcated structure along the second direction satisfies the following relationship: 0<D≤(P+S) / 2; Wherein, P is the width of the welding strip along the second direction, and S is the distance between two adjacent welding strips along the second direction.

12. The solar cell according to claim 1, characterized in that The angle α between the first direction and the third direction satisfies the following relationship: 0<tanα≤P / L; Wherein, L is the total length of the farthest ends of the first battery cell and the last battery cell in the battery string along the first direction, and P is the width of the welding strip along the second direction.

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

14. The solar cell according to claim 1, characterized in that In the second direction, the width of the welding strip is greater than or equal to the width of the fine grid; or In the second direction, the width of the welding strip is smaller than the width of the fine grid.

15. The solar cell according to claim 1, characterized in that The battery cell also includes a third battery cell, which is arranged between the first battery cell and the second battery cell, and the first fine grid and / or the second fine grid of the third battery cell are provided with the first forked segment at one end close to the first battery cell, and the first fine grid and / or the second fine grid of the third battery cell are provided with the second forked segment at one end close to the second battery cell.

16. The solar cell according to claim 1, characterized in that The soldering ribbon is inclined at one end away from the second battery cell toward the first edge, and the soldering ribbon is inclined at one end away from the first battery cell toward the second edge.

17. A battery assembly, characterized in that: Comprising the solar cell according to any one of claims 1 to 16.

18. A photovoltaic system, characterized in that: Comprising the battery assembly as claimed in claim 17.

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