Solar cell module and solar cell

Abstract

A solar cell module and a solar cell. The solar cell module comprises: a plurality of solar cells, each of the plurality of solar cells comprising a semiconductor substrate, first electrodes, and second electrodes; a plurality of first connecting electrodes disposed on a first surface of the semiconductor substrate, extending in a second direction, and distributed at intervals in a first direction; and a plurality of wires extending in the second direction, the plurality of wires being configured to electrically connect the first electrodes of a first solar cell to the second electrodes of a second solar cell adjacent to the first solar cell. Each of the plurality of first connecting electrodes at least partially overlaps with and is electrically connected to the plurality of wires; and the number of the first connecting electrodes is less than the number of the wires. A solar cell is divided into a left half region and a right half region by taking the center line of the solar cell in the first direction as a boundary; and the left half region and the right half region have the same number of first connecting electrodes, and / or a plurality of wires close to the center line are connected to the first connecting electrodes.

Description

Solar cell module and solar cell TECHNICAL FIELD

[0001] The present application relates to the technical field of solar cells, and in particular to a solar cell module and a solar cell. BACKGROUND

[0002] A solar cell is a clean energy device that directly converts solar energy into electrical energy, and the core part thereof is a solar cell piece. The main structure of the solar cell piece includes a silicon wafer, a PN junction, an anti-reflection layer, an electrode, and the like. Among them, the design and fabrication of the electrode have an important influence on the performance of the solar cell.

[0003] In order to reduce the shading area and save paste, a main grid-free (0BB) structure is currently adopted. However, due to the cancellation of the main grid, the welding quality is unstable, and problems such as false welding are prone to occur, and in the component stage (i.e., when the solar cell module is formed), it will cause the solar cell piece to warp, which will affect the normal work of the solar cell, and in turn affect the solar cell component efficiency. Secondly, in actual application, the efficiency improvement effect is not obvious, because the resistance loss of the 0BB design is still large. SUMMARY

[0004] In view of the above problems, the embodiments of the present application provide a solar cell module and a solar cell.

[0005] One aspect of the present application provides a solar cell module, comprising: a plurality of solar cells, each of the plurality of solar cells comprising a semiconductor substrate and a first electrode disposed on a first surface of the semiconductor substrate, extending along a first direction and spaced apart in a second direction; and a second electrode disposed on a second surface of the semiconductor substrate, extending along the first direction and spaced apart in the second direction; the first surface is opposite to the second surface; the first direction intersects the second direction;

[0006] a plurality of first connection electrodes disposed on the first surface of the semiconductor substrate, extending along the second direction and spaced apart along the first direction;

[0007] a plurality of wirings extending along the second direction, the plurality of wirings being configured to electrically connect the first electrode of a first solar cell in the plurality of solar cells to the second electrode of a second solar cell adjacent to the first solar cell;

[0008] The first connecting electrode is in contact with at least half of the first electrodes, or the extension length of the first connecting electrode in the second direction is greater than half of the length of the solar cell in the second direction; and at least part of each of the plurality of first connecting electrodes overlaps and is electrically connected with the plurality of wirings;

[0009] The number of the first connecting electrodes is less than the number of the wirings.

[0010] The solar cell is divided into a left half region and a right half region with the center line of the solar cell in the first direction as a boundary.

[0011] The left half region and the right half region have the same number of first connecting electrodes, and / or the plurality of wirings close to the center line are connected with the first connecting electrodes.

[0012] According to an embodiment of the present application, the number of the first connecting electrodes is twice the number of the wirings.

[0013] According to an embodiment of the present application, the number of the wirings is an even number, and / or the number of the first connecting electrodes is an even number greater than or equal to 6.

[0014] According to an embodiment of the present application, the difference between twice the number of the first connecting electrodes and the number of the wirings is 2 or 4 or 6.

[0015] According to an embodiment of the present application, the two wirings located at the outermost sides in the first direction at least partially cover the first connecting electrodes.

[0016] According to an embodiment of the present application, along the two ends in the first direction towards the center of the solar cell, the wirings alternately cover the first connecting electrodes, respectively.

[0017] According to an embodiment of the present application, further comprising:

[0018] A plurality of first short connecting electrodes are arranged on the first surface, the first short connecting electrodes extend in the second direction and are arranged at opposite end regions of the first surface in the second direction, the first short connecting electrodes connect 2-5 first electrodes in a cross manner with the first electrodes, and the first short connecting electrodes are in contact with wirings that are not connected with the first connecting electrodes.

[0019] According to embodiments of the present application, the first connection electrodes and the first short connection electrodes are arranged in an alternating manner from two ends of the first direction to the center, respectively; in the arrangement of the first connection electrodes and the first short connection electrodes, the two ends closest to the solar cell along the first direction are two of the first connection electrodes.

[0020] According to embodiments of the present application, further comprising:

[0021] a plurality of first fish-tail structures disposed on the first surface, extending along the second direction and spaced along the first direction; the plurality of first fish-tail structures are located in the end region along the second direction; the opening of the first fish-tail structure faces outward along the second direction; the first fish-tail structure is in contact with one end of the plurality of first connection electrodes.

[0022] According to embodiments of the present application, the first fish-tail structure further comprises a first tail pad, the first tail pad is disposed at the end of the first fish-tail structure close to the inside of the solar cell, and the first tail pad at least overlaps the wiring portion.

[0023] According to embodiments of the present application, further comprising:

[0024] a plurality of second connection electrodes disposed on the second surface of the semiconductor substrate, extending along the second direction and spaced along the first direction; the second connection electrodes are in contact with at least half of the second electrodes, or the extension length of the second connection electrodes along the second direction is greater than half of the length of the solar cell along the second direction; the wiring covered with the first connection electrodes of the first solar cell is also covered with the second connection electrodes of the second solar cell.

[0025] According to embodiments of the present application, the second connection electrodes and the first connection electrodes at least partially overlap in projection on the semiconductor substrate.

[0026] According to embodiments of the present application, further comprising:

[0027] a plurality of first tail pads disposed on the first surface, the plurality of first tail pads are located in the end region along the second direction and are spaced along the first direction; the first tail pads are connected with the wiring;

[0028] The solar cell has first and second edges extending along the second direction and opposite to each other;

[0029] The first edge tail pads and the second edge tail pads are arranged in the second direction.

[0030] A distance between the first edge tail pad and the middle tail pad adjacent to the first edge tail pad is D0, and a distance between the first edge tail pad and the first edge is D2; wherein 1 < D2 / D0 < 1.6, and / or, D0 and D2 are both less than 10 mm.

[0031] According to the embodiments of the present application, further comprising:

[0032] A plurality of first tail pads are arranged on the first surface, and the plurality of first tail pads are arranged at an end region in the second direction and are spaced apart in the first direction.

[0033] A plurality of third tail pads are arranged on the first surface and are adjacent to the end region, and the third tail pads are spaced apart from the first tail pads in the second direction.

[0034] At least one first sub-pad is arranged between the first tail pad and the third tail pad, and a width of the first sub-pad in the second direction is respectively less than a width of the first tail pad in the second direction, a width of the third tail pad in the second direction; and / or, a length of the first sub-pad in the first direction is respectively less than a length of the first tail pad in the first direction, a length of the third tail pad in the first direction.

[0035] The first tail pad, the third tail pad, and the sub-pad are respectively connected with the wiring.

[0036] According to the embodiments of the present application, a first spacing between adjacent first electrodes in the second direction is provided, and a second spacing between the first tail pad and the third tail pad in the second direction is greater than or equal to twice the first spacing and less than five times the first spacing; and / or, the second spacing between the first tail pad and the third tail pad is greater than or equal to 1.5 mm and less than or equal to 7 mm.

[0037] According to the embodiments of the present application, the first sub-pad includes a main body portion extending in the first direction and two overlapping portions formed at both ends of the main body portion, and an end portion of the main body portion is connected with a middle portion of the overlapping portion.

[0038] According to the embodiments of the present application, n wirings adjacent to the center line are connected with the first connection electrode, wherein n is an integer less than or equal to 6 and greater than or equal to 3.

[0039] According to embodiments of the present application, the number of the plurality of wirings is even, and the number n of the n wirings close to the center line is 4 or 6.

[0040] According to embodiments of the present application, the wirings are provided at the center line of the solar cell, and the wirings at and close to the center line are connected to the first connection electrodes.

[0041] According to embodiments of the present application, the first connection electrodes connected to the n wirings are symmetrically distributed with the center line as the center.

[0042] According to embodiments of the present application, the doped semiconductor layer of the solar cell includes doped regions and interval regions, the interval regions are provided between adjacent first electrodes, and the doped regions are provided at positions where the wirings are connected to the first connection electrodes, and the interval regions are formed at positions where the wirings are not connected to the first connection electrodes.

[0043] Another aspect of the present application provides a solar cell, comprising:

[0044] a semiconductor substrate;

[0045] first electrodes provided on a first surface of the semiconductor substrate, extending in a first direction, and spaced apart in a second direction; the first direction intersects the second direction;

[0046] a plurality of first connection electrodes provided on the first surface of the semiconductor substrate, extending in the second direction, and spaced apart in the first direction; the first connection electrodes are in contact with at least half of the number of the first electrodes, or the extension length of the first connection electrodes in the second direction is greater than half of the length of the solar cell in the second direction;

[0047] a plurality of first short connection electrodes provided on the first surface, extending in the second direction, and provided at opposite end regions of the first surface in the second direction, the first short connection electrodes connect 2-5 first electrodes in a manner intersecting the first electrodes;

[0048] the number of the first connection electrodes is an even number greater than or equal to 6; the first connection electrodes and the first short connection electrodes are arranged from both ends of the first direction to the center in an alternating manner; in the arrangement of the first connection electrodes and the first short connection electrodes, the two closest to the two ends of the solar cell in the first direction are the two of the plurality of first connection electrodes.

[0049] According to embodiments of the present application, the solar cell further comprises:

[0050] a plurality of second connection electrodes disposed on the second surface of the semiconductor substrate, extending in the second direction and spaced apart in the first direction; the second connection electrodes contact-connect at least half of the second electrodes, or the second connection electrodes have an extension length in the second direction greater than half of the length of the solar cell in the second direction;

[0051] a plurality of second short connection electrodes disposed on the second surface, extending in the second direction and disposed at opposite end regions of the second surface in the second direction, the second short connection electrodes contact 2-5 second electrodes in a crossing manner;

[0052] the projection of the second connection electrodes on the semiconductor substrate at least partially overlaps the projection of the first connection electrodes on the semiconductor substrate; and the projection of the second short connection electrodes on the semiconductor substrate at least partially overlaps the projection of the first short connection electrodes on the semiconductor substrate.

[0053] According to embodiments of the present application, in the arrangement of the first connection electrodes and the first short connection electrodes, the first connection electrodes close to the center line of the semiconductor substrate are n in number, where n is an integer less than or equal to 6 and greater than or equal to 3.

[0054] Yet another aspect of the present application provides a solar cell, comprising:

[0055] a semiconductor substrate;

[0056] a first electrode disposed on a first surface of the semiconductor substrate, extending in a first direction and spaced apart in a second direction; the first direction intersects the second direction;

[0057] a plurality of first connection electrodes disposed on the first surface, extending in the second direction and spaced apart in the first direction;

[0058] a plurality of first tail pads disposed on the first surface, located at end regions in the second direction and spaced apart in the first direction;

[0059] the first connection electrodes contact-connect at least half of the first electrodes, or the first connection electrodes have an extension length in the second direction greater than half of the length of the solar cell in the second direction;

[0060] the number of the plurality of first connection electrodes is less than the number of the first tail pads; and each of the first connection electrodes is connected to one of the first tail pads;

[0061] The semiconductor substrate has first and second edges extending along the second direction and opposite to each other, and each of the first tail pads closest to the first and second edges is connected with the first connecting electrode; and at least three of the first tail pads close to the center line of the semiconductor substrate are connected with the first connecting electrode.

[0062] According to the embodiments of the present application, under the double-sided cell frame, by arranging the first connecting electrodes distributed at intervals, the light-shielding area and the resistance loss of the solar cell surface can be balanced. Meanwhile, the partial wiring is connected with the connecting electrodes distributed at intervals to sequentially connect the front and back surfaces of different cell pieces, which also increases the bonding force between the welding wire and the cell piece, overcomes the unstable welding quality and large surface resistance loss, and meanwhile, by optimizing the connection form between the first connecting electrode and the wiring, the warping of the cell piece can be effectively inhibited, thereby achieving the technical effects of improving the solar cell efficiency and service life. BRIEF DESCRIPTION OF DRAWINGS

[0063] The above content and other purposes, features and advantages of the present application will be more apparent from the following description of the embodiments of the present application with reference to the accompanying drawings, in which:

[0064] Fig. 1 schematically shows the overall structure of a solar cell module according to an embodiment of the present application;

[0065] Fig. 2 schematically shows the structure of the front surface of a solar cell before slicing according to an embodiment of the present application;

[0066] Fig. 3 schematically shows the structure of the front surface of a solar cell after slicing according to an embodiment of the present application;

[0067] Fig. 4 schematically shows a partial enlarged structure of a solar cell according to an embodiment of the present application;

[0068] Fig. 5 schematically shows a partial structure of the back surface of a solar cell containing small pads according to an embodiment of the present application;

[0069] Fig. 6 schematically shows a partial structure of a solar cell containing an antenna according to an embodiment of the present application.

[0070] Fig. 7 schematically shows a structure of a solar cell including a doped region and an interval region according to an embodiment of the present application.

[0071] Fig. 8 schematically shows a structure of a solar cell including different pad structures according to an embodiment of the present application.

[0072] Fig. 9 schematically shows an enlarged structure of a small pad according to an embodiment of the present application.

[0073] FIG. 10 schematically shows a structure enlarged view of a tail pad with an auxiliary soldering portion.

[0074] FIG. 11 schematically shows a structure view of a solar cell with an odd number of first connection electrodes.

[0075] [Explanation of Reference Numerals] 1 - solar cell; 11 - semiconductor substrate; 12 - first electrode; 13 - second electrode; 14 - first connection electrode; 15 - wiring; 16 - second connection electrode; 17 - first short connection electrode; 18 - second short connection electrode; 19 - first fish structure; 20 - second fish structure; 21 - first tail pad; 211 - auxiliary soldering portion; 22 - second tail pad; 23 - small pad; 231 - first small pad; 21-1 - first edge tail pad; 21-3 - second edge tail pad; 21-5 - middle tail pad; 111 - first edge; 112 - second edge; 2310 - main portion; 2312 - lap portion; 232 - second small pad; 233 - third small pad; 24 - antenna; 25 - third tail pad; 26 - fourth tail pad; 28 - fifth tail pad; 101 - first solar cell; 102 - second solar cell. DETAILED DESCRIPTION

[0076] For the purpose of making the object, technical solutions and advantages of the present application clearer, further detailed description will be made to the present application with reference to the embodiments and the accompanying drawings.

[0077] It should be noted that similar or identical parts are denoted by the same reference numerals in the accompanying drawings or the description. The technical features in the embodiments shown in the description can be freely combined to form new solutions without conflict, and each claim can be used as an embodiment alone or the technical features in the claims can be combined to form new embodiments. In the accompanying drawings, the shape or thickness of the embodiments can be exaggerated and simplified for the purpose of convenience or clear illustration. Furthermore, elements or implementation manners not shown or described in the accompanying drawings are known to those skilled in the art. In addition, although examples can be provided herein with parameters containing specific values, it should be understood that the parameters do not need to be exactly equal to the corresponding values, but can be approximately equal to the corresponding values within an acceptable error range or design constraint.

[0078] Unless there is a technical obstacle or conflict, the above various embodiments of the present application can be freely combined to form additional embodiments, and these additional embodiments are within the protection scope of the present application.

[0079] Although the present application is illustrated with reference to the accompanying drawings, the embodiments disclosed in the drawings are intended to exemplify the preferred embodiments of the present application and should not be understood as a limitation to the present application. The dimensional proportions in the drawings are merely illustrative and should not be understood as a limitation to the present application.

[0080] Although some embodiments of the present general inventive concept have been described and shown, it is to be understood that those skilled in the art who fall within the scope of the present general inventive concept can make many alterations, modifications and additions thereto without departing from the spirit and scope of the present general inventive concept as set forth in the appended claims and their equivalents.

[0081] FIG. 1 schematically illustrates an overall structure of a solar cell module according to an embodiment of the present application. FIG. 2 schematically illustrates a structure of a front surface of a solar cell according to an embodiment of the present application. FIG. 3 schematically illustrates a structure of a front surface of a solar cell after being cut according to an embodiment of the present application.

[0082] According to an embodiment of the present application, as shown in FIG. 1, FIG. 2 and FIG. 3, the present application provides a solar cell module, for example, including a plurality of solar cells 1 each including a semiconductor substrate 11, and a first electrode 12 disposed on a first surface of the semiconductor substrate 11, extending in a first direction x, and spaced apart in a second direction y. And, a second electrode 13 disposed on a second surface of the semiconductor substrate 11, extending in the first direction x, and spaced apart in the second direction y (as shown in FIG. 5). The first surface is opposite to the second surface. The first direction x intersects the second direction y. A plurality of first connection electrodes 14 are disposed on the first surface of the semiconductor substrate 11, extending in the second direction y, and spaced apart in the first direction x. The solar cell module further includes a plurality of wirings 15 extending in the second direction y, the plurality of wirings 15 are configured to electrically connect the first electrode 12 of a first solar cell 101 among the plurality of solar cells 1 to the second electrode 13 of a second solar cell 102 adjacent to the first solar cell 101. The first connection electrode 14 is in contact with at least half of the number of the first electrode 12, or the first connection electrode 14 has an extension length in the second direction y greater than half of a length of the solar cell 1 in the second direction y. At least a portion of each of the plurality of first connection electrodes 14 overlaps with the plurality of wirings 15 to form an electrical connection therewith. The number of the first connection electrodes 14 is twice greater than the number of the wirings 15, and the number of the first connection electrodes 14 is less than the number of the wirings 15.

[0083] It should be noted that Fig. 2 is the structure of two solar cells before being split. After the printing of the electrodes, the two solar cells can be split from the middle. The wires 15 are used to connect the multiple split solar cells in sequence to form a solar cell module. Fig. 1 only schematically shows the way of connecting the solar cells to form a solar cell module, and does not limit the form of the solar cells.

[0084] In some embodiments, the semiconductor substrate 11 can be a single crystal silicon wafer or a polycrystalline silicon wafer, and the thickness can be 100 microns, 110 microns, 120 microns, 130 microns, 140 microns, 160 microns, 180 microns, or 200 microns.

[0085] The first electrode 12 and the second electrode 13 can be in direct contact with the doped semiconductor layer of the solar cell to collect the photo-generated carriers, and can be realized by printing a conductive paste or by a deposition process such as electroplating, with a width ranging from 8 to 20 microns, commonly referred to as a fine grid or current collection layer.

[0086] The width of the first connecting electrode 14 ranges from 10 to 30 microns. The material of the first connecting electrode 14 can be the same as or different from that of the first electrode 12. The first electrode 12 needs to pass through the passivation film on the surface of the solar cell to collect electrons. The first connecting electrode 14 can pass through the passivation film on the surface of the solar cell to collect electrons, or can only be electrically connected to the first electrode 12 and the wire 15 to collect the current of the first electrode 12 and strengthen the welding.

[0087] On the first surface, in addition to the first electrode 12, there are a series of first connecting electrodes 14 with a width close to that of the first electrode 12, which are perpendicular to the first electrode (i.e., extend along the second direction) and are spaced apart in the first direction. The width and position of these first connecting electrodes are designed to enable them to contact at least half the number of wires 15 to ensure good current collection and distribution. Furthermore, by arranging each first connecting electrode 14 to contact at least half the number of first electrodes 12 or by arranging its length to be greater than half the length of the solar cell in the second direction y, the first connecting electrode 14 can more fully collect the current generated on the solar cell and ensure sufficient contact with the wire 15 to better transmit the current and ensure the power generation efficiency of the solar cell module.

[0088] The width of the first connecting electrode 14 of the embodiment of the present application is close to that of the first electrode 12, which increases the contact with the solder strip while minimizing the light-shielding area, reduces the resistance loss on the surface of the cell, and is beneficial to improving the efficiency and service life of the cell. In addition, the first connecting electrode 14 with a narrower width consumes less metal paste and has higher cost efficiency.

[0089] The wiring 15 is, for example, a metal ribbon, which is used to electrically connect the front and back of adjacent solar cells and ensure a certain structural strength.

[0090] As an implementation, the wiring 15 is a round metal ribbon, which includes a round metal wire as a core layer and a solder attached to the surface of the metal wire. The round metal ribbon extends along the second direction to connect the first electrode 12 on the front of one solar cell to the second electrode 13 on the back of an adjacent solar cell. In this case, a part of the round metal ribbon covers the first connecting electrode 14 and is electrically connected to the first connecting electrode 14 to increase the bonding force between the wiring 15 and the solar cell. At the same time, since the length of the first connecting electrode 14 along the second direction is less than the length of the semiconductor substrate, the metal ribbon does not form excessive solder adhesion at the end of the semiconductor substrate, which helps to reduce the pulling force of the metal ribbon on the edge of the solar cell, thereby reducing the risk of hidden cracks caused by edge stress concentration. The number of wirings 15 is less than twice the number of first connecting electrodes 14 and greater than the number of first connecting electrodes 14, so that each first connecting electrode is stably soldered to the metal ribbon to improve the overall soldering force and form an effective current transmission network.

[0091] A plurality of solar cells are connected in series by the above wiring method to form a module. Then, the entire module is encapsulated between a transparent front cover plate and a back plate to protect the cells from the environment and enhance their durability.

[0092] Figure 7 schematically shows a structural diagram of a solar cell including a doped region and a spacing region according to an embodiment of the present application. According to an embodiment of the present application, as shown in Figure 7, the doped semiconductor layer of the solar cell can include a doped region 113 and a spacing region 115. The spacing region 115 is arranged between adjacent first electrodes 12, and the doped region 113 is arranged at the position where the wiring 15 is connected to the first connecting electrode 14, and the spacing region 115 is formed at the position where the wiring 15 is not connected to the first connecting electrode 14. Specifically, the doped region 113 refers to a region in the semiconductor layer where there is doped polysilicon, and the spacing region refers to a region where there is no polysilicon. By forming a spacing region without polysilicon between the first electrodes 12, the parasitic absorption of light can be reduced, the reflectivity can be reduced, and the power generation capability of the cell can be improved. The doped region arranged at the position where the wiring 15 is connected to the first connecting electrode 14 has at least the following advantages: 1. Since the first connecting electrode 14 can burn through the passivation layer when it is arranged, resulting in the formation of a recombination center between the first connecting electrode 14 and the silicon substrate, affecting the power generation efficiency, therefore, the doped polysilicon is retained at the position corresponding to the first connecting electrode 14, which can reduce the risk caused by the burning of the first connecting electrode 14; 2. Since the spacing region 115 arranged on the semiconductor layer is usually formed by an etching process, if the spacing region 115 is formed at the position of the first connecting electrode 14, a pit will be formed on the semiconductor substrate of the solar cell, affecting the printing consistency of the first connecting electrode 14, increasing the transmission resistance, and affecting the current collection capability; at the same time, since the pit formed by the spacing region 115 affects the flatness of the cell surface, when the wiring 15 is connected to the first connecting electrode 14, it can also cause the contact area between the two to decrease, affecting the connection strength, increasing the resistance, and reducing the current transmission capability, thereby affecting the overall power generation efficiency of the solar cell module. Therefore, the doped region 113 arranged at the position where the wiring 15 is connected to the first connecting electrode 14 can reduce the above risks. At the position where the wiring 15 is not connected to the first connecting electrode 14, there is no combination problem between the wiring 15 and the connecting electrode, therefore, by forming the spacing region 115 at this position, the parasitic absorption of light can be further reduced without affecting the current transmission capability of the wiring, and the power generation capability of the cell can be improved.

[0093] According to the embodiment of the present application, as the solar cell after being diced, as shown in FIG. 3, the solar cell 1 includes a long side extending along a first direction x and a short side extending along a second direction y. The first connecting electrode 14 extends along the second direction y, and the length of the first connecting electrode 14 extending along the second direction y is greater than half of the length of the short side to ensure the welding stability between the first connecting electrode 14 and the wiring 15. In the embodiment, the number of the wiring 15 is even and greater than 10. The two wirings 15 located at the outermost sides along the first direction x at least partially cover the first connecting electrode 14. And along the two ends of the first direction x, the wirings 15 alternately cover the first connecting electrode 14 respectively towards the center of the solar cell 1.

[0094] As a preferred implementation, the solar cell is divided into two regions, for example, a left half region and a right half region, with the center line of the cell in the long side direction as the boundary. The left and right half regions respectively have the same number of first connecting electrodes 14, so that the stress in the long side direction of the cell can be balanced.

[0095] As a preferred implementation, the solar cell is divided into two regions, for example, a left half region and a right half region, with the center line of the cell in the long side direction as the boundary. The left and right half regions respectively have the same number of first connecting electrodes 14, so that the stress in the long side direction of the cell can be balanced.

[0096] As a preferred implementation, the solar cell is divided into two regions, for example, a left half region and a right half region, with the center line of the cell in the long side direction as the boundary. The left and right half regions respectively have the same number of first connecting electrodes 14, so that the stress in the long side direction of the cell can be balanced.

[0097] As a preferred implementation, the left half region and the right half region are provided with the same number of first connecting electrodes 14, and the number of wirings 15 in the left half region is odd, and the number of wirings 15 in the right half region is odd. The wirings 15 are connected to the first connecting electrodes 14 at intervals, that is, in each of the left and right half regions, the wirings and the first connecting electrodes are alternately arranged along the second direction, for example, the first, third, fifth and seventh wirings are connected to the first connecting electrodes, while the second, fourth and sixth wirings are not provided with the first connecting electrodes at the corresponding positions. This arrangement can more evenly balance the welding tension points and form a reinforced welding tension in the middle region of the cell, so that the warping of the cell can be more effectively suppressed.

[0098] It should be noted that the line layout features shown in FIG. 3 are also applicable to the back surface of the solar cell, which will not be described here again.

[0099] According to embodiments of the present application, as shown in FIG. 2 and FIG. 3, the solar cell 1 can further include a plurality of first fish-tail structures 19 disposed on the first surface, extending along the second direction y and spaced apart along the first direction x. The plurality of first fish-tail structures 19 are located at the end region in the second direction y. The openings of the first fish-tail structures 19 face outwardly of the cell along the second direction y. The first fish-tail structures 19 are in contact with one end of the plurality of first connecting electrodes 14 and the plurality of first short connecting electrodes 17. The first fish-tail structures 19 are arranged in pairs, the number of which is twice the number of wires connected thereto, and are arranged one-to-one with the wires at the end, the first connecting electrodes 14 continuously extend in the second direction, and the two ends are respectively electrically connected to the first fish-tail structures 19. Of course, the first fish-tail structures 19 on one side can be omitted, for example, only the first fish-tail structures 19 are arranged on one long side of the solar cell. The arrangement of the first fish-tail structures 19 can avoid the adverse effects caused by the offset of the wires 15 at the end of the cell.

[0100] FIG. 4 schematically shows a partial enlarged structural view of a solar cell according to embodiments of the present application.

[0101] According to embodiments of the present application, as shown in FIG. 3 and FIG. 4, the first fish-tail structure 19 further includes a first tail pad 21, the first tail pad 21 is disposed at the end of the first fish-tail structure 19 close to the inside of the solar cell 1, and the first tail pad 21 at least partially overlaps the wire 15.

[0102] In some embodiments, the first tail pad 21 is added to the first fish-tail structure 19 to further enhance the transmission of current and the stability of the connection of the wire.

[0103] In some embodiments, it can be understood that the first fish-tail structure 19 can not be arranged on the solar cell, and only the first tail pad 21 is arranged. The plurality of first tail pads 21 are located at the end region of the first surface in the second direction and are spaced apart along the first direction, and the first tail pads 21 are connected with the wires 15. As shown in FIG. 3, the solar cell 1 has a first edge 111 and a second edge 112 extending along the second direction and opposite to each other. The plurality of first tail pads 21 include a first edge tail pad 21-1 close to the first edge 111, a second edge tail pad 21-3 close to the second edge 112, and an intermediate tail pad 21-5 located between the first edge tail pad 21-1 and the second edge tail pad 21-3.

[0104] The distance D0 between the first edge tail pad 21-1 and the middle tail pad 21-5 adjacent to the first edge tail pad 21-1 is less than the distance D2 between the first edge tail pad 21-1 and the first edge 111 of the solar cell, and the ratio D2 / D0 of D2 to D0 is less than 1.6. Specifically, D0 refers to the distance between the first edge tail pad 21-1 and the center line of the middle tail pad 21-5 in the second direction; D2 refers to the distance between the center line of the first edge tail pad 21-1 in the second direction and the first edge 111 of the solar cell.

[0105] According to the above embodiment, the distance between the edge tail pad closest to the edge of the solar cell and the edge of the solar cell is set to be greater than the distance between the edge tail pad and the adjacent middle tail pad, and the ratio is less than 1.6, which can maximize the current collected from the solar cell area and improve the overall current output performance of the solar cell module.

[0106] Preferably, the values of D0 and D2 are both set to be less than 10 mm to maximize the current generated by each area of the solar cell. Further preferably, the distances between the wires are equal to ensure the stability of the current output.

[0107] It can be understood that the fish-tail structure or the tail pad structure can also be arranged on the second surface of the solar cell semiconductor substrate 11 in the above manner.

[0108] According to the embodiment of the present application, as shown in FIGS. 3 and 4, the solar cell module further comprises a plurality of first short connection electrodes 17 arranged on the first surface, the first short connection electrodes 17 extending along the second direction y and arranged at the opposite end regions of the first surface along the second direction y, the first short connection electrodes 17 being connected to 2-5 first electrodes 12 in a crossing manner with the first electrodes 12 (wherein the first short connection electrodes 14 extend along the second direction y and the first electrodes 12 extend along the first direction x, so that the connection between them is formed in a crossing manner in the extension direction), and the first short connection electrodes 17 being in contact with the wires 15 that are not connected to the first connection electrodes 14. The first connection electrodes 14 and the first short connection electrodes 17 are arranged in an alternating manner from the two ends of the first direction x to the center, respectively. In the arrangement of the first connection electrodes 14 and the first short connection electrodes 17, the two closest to the two ends of the solar cell along the first direction x are two of the plurality of first connection electrodes 14.

[0109] In some embodiments, the plurality of first short connection electrodes 17 are in contact with at least one of the plurality of wirings 15 that is not in direct contact with the first connection electrode 14. As shown in FIG. 4, the first short connection electrode 17 is disposed at the tail of the first fishhook structure 19 that is not connected with the first connection electrode 14, and is connected with the first tail pad 21 of the first fishhook structure 19. Meanwhile, the first short connection electrode 17 is in cross connection with a certain number of the first electrodes 12, and the number of the first electrodes in cross connection with the first short connection electrode 17 is no more than 5, so as to control the cost on the basis of ensuring stable connection with the wirings 15. The difference between the first connection electrode 14 and the first short connection electrode 17 is that the first connection electrode 14 is more concerned about the overall enhancement of the welding stability with the wirings 15 in the second direction of the battery, while the first short connection electrode 17 only needs to consider the supplementary enhancement of the connection of the wirings at a specific position, such as the position of the end of the solar cell, so as to avoid the deviation of the wirings. In combination with the reasonable layout of the first connection electrode 14 and the first short connection electrode 17, the cost and the welding stability can be balanced as a whole.

[0110] FIG. 5 schematically shows a partial structure diagram of the back surface of a solar cell containing small pads according to an embodiment of the present application.

[0111] According to an embodiment of the present application, as shown in FIG. 5, the solar cell module further comprises a plurality of second connection electrodes 16 disposed on the second surface of the semiconductor substrate 11 and extending along the second direction y, and spaced apart along the first direction x. The second connection electrode 16 is in contact with at least half the number of the second electrodes 13, or the extension length of the second connection electrode 16 in the second direction y is greater than half the length of the solar cell 1 in the second direction y. The wiring 15 in covering connection with the first connection electrode 14 of the first solar cell 101 is also in covering connection with the second connection electrode 16 of the second solar cell 102. The solar cell module further comprises a plurality of second short connection electrodes 18 disposed on the second surface, the second short connection electrodes 18 extending along the second direction y and being disposed at the opposite end regions of the second surface along the second direction y, and the second short connection electrodes 18 are in cross connection with 2-5 second electrodes 13 in a cross manner. The projection of the second connection electrode 16 and the first connection electrode 14 on the semiconductor substrate at least partially overlaps. The projection of the second short connection electrode 18 and the first short connection electrode 17 on the semiconductor substrate 11 at least partially overlaps.

[0112] In some embodiments, the second surface of the solar cell 1 comprises a second surface electrode structure, which can have the same or similar design as the above-mentioned first surface electrode structure, for example, can comprise a second electrode 13, a second connecting electrode 16, a second fish-tail structure 20, a second short connecting electrode 18, and a second tail pad 22. In a preferred solution, the number of the second electrodes 13 is greater than the first electrodes 12. The number and distribution of the second connecting electrodes 16 are the same as the first connecting electrodes 14, but the end positions of the first connecting electrodes 14 and the second connecting electrodes 16 can be staggered in the second direction, because the first tail pad 21 and the second tail pad 22 of the front and back surfaces are generally staggered in the second direction to avoid the problem of stress concentration of the front and back surfaces. The number and distribution of the second connecting electrodes 16 are the same as the first connecting electrodes 14, which is conducive to the balance of the overall tension of the front and back surfaces, and avoids the warping and hidden cracking of the solar cell. In addition, the first connecting electrodes 14 and the second connecting electrodes 16 are arranged to at least partially overlap in projection on the semiconductor substrate, and when the solar cells are connected to form a solar cell module, the wiring can be connected to the first connecting electrodes 14 and the second connecting electrodes 16 of adjacent solar cells at the same time, forming a stable and consistent current transmission path on the entire wiring, increasing the electrical contact area of the wiring, reducing the current transmission resistance, and more conducive to the export and transmission of current on the solar cell; at the same time, it is conducive to the balance of the tension between adjacent solar cell pieces, and ensures the overall reliability of the solar cell module.

[0113] As an implementation manner of the present application, as shown in FIG. 5, a small pad 23 can also be added at the intersection of the first electrode 12 and the wiring 15 to enhance the welding. The shape of the small pad 23 can be rectangular or gradually changing in width. When the small pad is rectangular, the length ranges from 0.8 mm to 2 mm, and the width ranges from 0.2 mm to 1 mm.

[0114] FIG. 8 schematically shows a structural diagram of a solar cell comprising different pad structures according to an embodiment of the present application. As shown in FIG. 8, according to any one of the embodiments of the present application, the solar cell module can further comprise a third tail pad 25 arranged on the first surface of the semiconductor substrate 11 in the region close to the end, the third tail pad 25 is arranged spaced apart from the first tail pad 21 along the second direction, and at least one first small pad 231 is arranged between the first tail pad 21 and the third tail pad 25. The size of the first small pad 231 can be one of the following three cases: one, the width of the first small pad 231 along the second direction is smaller than the width of the first tail pad 21 along the second direction and the width of the third tail pad 25 along the second direction, respectively; two, the length of the first small pad 231 along the first direction is smaller than the length of the first tail pad 21 along the first direction and the length of the third tail pad 25 along the first direction, respectively; three, the size of the first small pad 231 meets the above conditions at the same time.

[0115] Specifically, the first tail pad 21, the first small pad 231 and the third tail pad 25 are arranged on the first electrode 12 and connected with the first electrode 12 and the wiring 15.

[0116] The first tail pad 21 and the third tail pad 25 have a second interval in the second direction, which is greater than or equal to twice the first interval and less than or equal to five times the first interval. Alternatively, the second interval between the first tail pad 21 and the third tail pad 25 is greater than or equal to 1.5 mm and less than or equal to 7 mm. Specifically, the second interval refers to the distance between the center lines of the first tail pad 21 and the third tail pad 25 in the first direction.

[0117] The length of the first tail pad 21 in the first direction is L1, the length of the third tail pad 25 in the first direction is L2 (not shown in the figure), and the length of the first small pad 231 in the first direction is L3 (not shown in the figure), wherein the ratio of L1 or L2 to L3 is less than 1 and greater than or equal to 0.5, specifically, 0.7 mm≤L1 or L2≤1.5 mm, for example, preferably 0.8 mm or 1.0 mm, 1.2 mm; 0.5 mm≤L3≤1 mm, preferably 0.6 mm or 0.7 mm.

[0118] The width of the first tail pad 21 in the second direction is D1 (shown in FIG. 10), the width of the third tail pad 25 in the second direction is D3 (not shown in the figure), and the width of the first small pad 231 in the second direction is D4 (not shown in the figure), wherein the ratio of D1 or D3 to D4 is less than or equal to 0.6 and greater than or equal to 0.1, specifically, 0.2 mm≤D1 or D3≤0.5 mm, for example, preferably 0.3 mm or 0.4 mm; 0.03 mm≤D4≤0.2 mm, preferably 0.04 mm or 0.15 mm.

[0119] Further preferably, the lengths L1 and L2 of the first tail pad 21 and the third tail pad 25 can be the same, for example, L1=L2=1.2 mm, to ensure the balance of the end region welding stress.

[0120] By arranging the first tail pad 21 and the third tail pad 25 with a larger length at the end region of the solar cell and arranging the first small pad 231 with a shorter length between the first tail pad 21 and the third tail pad 25, the welding stability of the end region can be improved, while minimizing the current loss caused by the shading of the pads to the solar cell.

[0121] According to the above embodiment, the solar cell can further be provided with a plurality of third fish-tail structures opposite to the first fish-tail structures 19 at the other end region of the first surface, the plurality of third fish-tail structures extending along the second direction and being spaced apart along the first direction, the openings of the third fish-tail structures being directed out of the cell along the second direction; and a plurality of second small pads 232 being provided between the first fish-tail structures 19 and the third fish-tail structures, the wiring being connected to the first fish-tail structures, the third fish-tail structures and the plurality of second small pads 232.

[0122] The solar cell can further be provided with a fourth tail pad 26, a third small pad 233 and a fifth tail pad 28 being sequentially and spaced apart from each other along the second direction from the end region towards the middle region at the other end region of the first surface, a plurality of second small pads 232 being provided between the third tail pad 25 and the fifth tail pad 28 which are relatively close to the middle region, and the wiring 15 being connected to the first tail pad 21, the first small pad 231, the third tail pad 25, the second small pads 232, the fifth tail pad 28, the third small pad 233 and the fourth tail pad 26.

[0123] It can be understood that in the above embodiments, the fish-tail structures connected to the tail pads of the end region can be provided or not provided.

[0124] FIG. 9 schematically shows a structure enlarged view of a small pad according to an embodiment of the present application. Referring to FIG. 9, in some embodiments, each small pad can include a main body portion extending along the first direction and two overlapping portions formed at both ends of the main body portion, and the end of the main body portion is connected to the middle of the overlapping portion. For example, taking the first small pad 231 as an example, the first small pad 231 includes a main body portion 2310 and two overlapping portions 2312, and the main body portion 2310 and the overlapping portions 2312 together form an H shape. The size of the overlapping portion 2312 in the second direction is greater than the size in the first direction. The main body portion 2310 partially overlaps or is parallel to the first electrode 12, and the overlapping portion 2312 intersects the first electrode 12. Specifically, the length of the main body portion 2310 in the first direction ranges from 0.4 mm to 1.0 mm, and is preferably 0.6 mm; and the width of the main body portion 2310 in the second direction ranges from 0.02 mm to 0.06 mm, and is preferably 0.04 mm. The length of the overlapping portion 2312 in the second direction ranges from 0.1 mm to 0.2 mm, and is preferably 0.15 mm; and the width of the overlapping portion 2312 in the first direction ranges from 0.03 mm to 0.08 mm, and is preferably 0.05 mm.

[0125] By setting the small pads with the body part and the overlapping part at the first electrode 12, on the one hand, the first electrode can be prevented from being disconnected from the wiring, the overlapping part is overlapped with the wiring, the fault tolerance is improved, and the current collection and output are ensured; on the other hand, by setting the overlapping part, the wiring can be prevented from being offset to form a disconnected welding, and the reliability of the welding is improved.

[0126] It should be noted that the small pads are collectively referred to as the first small pad 231, the second small pad 232, and the third small pad 233, and the tail pads are collectively referred to as the first tail pad to the fifth tail pad. The first small pad 231, the second small pad 232, and the third small pad 233 can be multiple. The size (length or width) of the small pad is smaller than the size of the tail pad. The size of each small pad can be equal or not equal, and no limitation is made thereto.

[0127] FIG. 10 schematically shows an enlarged view of the structure of the tail pad with the auxiliary welding part. Referring to FIG. 10, according to any of the above embodiments, an auxiliary welding part (as shown by 211 in FIG. 10) can also be provided at both ends of each tail pad in the first direction. The length of the auxiliary welding part in the first direction is L6, and 0.02mm≤L6≤0.06mm. Optionally, the length ratio of the tail pad to the auxiliary welding part satisfies 1.5≤(L1 or L2) / L6≤3.5. The width of the auxiliary welding part in the second direction is 0.02mm≤width≤0.08mm. Optionally, the width of the auxiliary welding part can gradually decrease outward from the end of the tail pad. By setting the auxiliary welding part, the first electrode 12 is overlapped with the auxiliary welding part to achieve the electrical connection between the first electrode 12 and the tail pad. The height difference caused by the first electrode under the tail pad can be avoided, and the tensile stress generated when the wiring is welded with the tail pad is increased.

[0128] As an implementation manner of the present application, the end region of the solar cell can also be provided with a plurality of tail pads with different sizes, and the lengths of the plurality of tail pads gradually decrease along the arrangement direction of the end region to the central region of the solar cell. For example, four tail pads can be provided in the end region, and the lengths of the four tail pads in the first direction are 1.2mm, 1.0mm, 0.8mm, and 0.7mm in sequence. Since the stress on the end region of the solar cell is the largest after the solar cell module is formed, by the setting, the tail pad with a larger size is provided closest to the end region of the solar cell, and the size of the tail pad gradually decreases close to the central region of the solar cell. The reliability of the welding is improved, and the influence of the tail pad on the current output efficiency of the solar cell is minimized as much as possible. It should be noted that the line layout features shown in FIG. 5 are also applicable to the front surface of the solar cell, and will not be described herein.

[0129] Figure 6 schematically shows a partial structure diagram of a solar cell containing a feeler according to an embodiment of the present application.

[0130] As an implementation manner of the present application, as shown in Figure 6, a feeler 24 can also be used instead of a small pad 23 at the intersection of the first electrode 12 and the wiring 15. The size parameters of the feeler 24 are, for example, 0.02 mm (edge width) * 0.04 mm (widest width) * 1.2 mm (length). The benefits of such design are: first, to improve the fault tolerance rate of the fuse of the thin grid at the lap joint of the solder strip during soldering. For the 0BB scheme of soldering first and then dispensing, when the solder melts at high temperature, the thin grid is more likely to be fused due to its thinness, causing the EL of the assembly to be black, and the design of the feeler can better avoid such phenomenon. Second, the thin grid has a narrow line width, and the contact with the solder strip is in point contact, which on the one hand causes a large line resistance of current conduction, causing the assembly to heat, and on the other hand, point contact greatly increases the risk of local tensile force unqualification, and the design of the feeler increases the contact points of the thin grid and the solder strip, which can effectively complete the transmission of photo-generated carriers while avoiding the risk of tensile force. At the same time, high temperature during series soldering will introduce flux and other organic matter into the contact point of the solder strip and the thin grid, and the feeler widens the contact point, reduces the resistance, and promotes current transmission. The feelers are uniformly distributed along the thin grid, and each feeler can form a good contact point with the solder strip during soldering. Uniform and large number of contact points can provide good tensile force effect for the battery string, and the role of the end solder in terms of tensile force can be relatively weakened, thereby reducing the solder to meet the cost reduction and efficiency increase.

[0131] According to the embodiments of the present application, it can be understood that each tail pad, small pad, feeler, etc. are different forms of electrical connection structures made of materials with soldering characteristics, which can provide a binding force between the wiring and the first electrode, the second electrode, the first connecting electrode, and the second connecting electrode, and form an electrical connection, for transmitting the current generated on the solar cell through the wiring.

[0132] The following takes 10 first connecting electrodes and 10 second connecting electrodes as an example to specifically introduce an embodiment of the present application:

[0133] Each cell has 10 first connecting electrodes and 10 second connecting electrodes. The number of wirings is 18, which meets the connection requirements of all connecting electrodes.

[0134] The first fishhook structure is arranged at both ends of the first surface (for example, the front surface), extends along the second direction, and is distributed at intervals along the first direction. The opening of the first fishhook structure is outward of the cell along the second direction, ensuring contact connection with one end of the first connecting electrode and the first short connecting electrode. These fishhook structures provide additional current collection paths, especially in the edge area of the cell, improving the transverse collection efficiency of the current.

[0135] The second fishhook structures are arranged at both ends of the second surface (e.g. the back surface), extend in the second direction, and are spaced apart in the first direction. The openings of the second fishhook structures also face outward in the second direction, ensuring contact with one end of the second connection electrodes and the second short connection electrodes. The second fishhook structures have a similar effect to the first fishhook structures, and are designed to optimize current collection in the edge region.

[0136] At both ends of the front surface of the cell sheet, the first fishhook structures will contact the first connection electrodes or the first short connection electrodes, ensuring effective collection and transmission of current in the edge region. The design of the fishhook structures can be multiple elongated metal wire segments, with one end of each metal wire segment bent or broken into a fishhook shape to contact the connection electrodes. For example, the width of the metal wire segments of the first fishhook structures is 40-50 μm, which is wider than the first connection electrodes and the first electrodes, facilitating the collection of current and improving the welding strength of the edges of the cell sheet.

[0137] At both ends of the back surface of the cell sheet, the second fishhook structures will contact the second connection electrodes or the second short connection electrodes, and have a similar effect of optimizing current collection and transmission in the edge region.

[0138] At both ends of the front surface of the cell sheet, there are 18 first fishhook structures corresponding to the wires one by one. Similarly, at both ends of the back surface of the cell sheet, there are 18 second fishhook structures corresponding to the wires one by one.

[0139] By introducing fishhook structures at both ends of the front and back surfaces of the cell sheet, the current collection in the edge region can be further enhanced, which is crucial for improving the overall performance and reliability of the module. The design of the fishhook structures not only increases the current collection points, but also improves the transverse transmission efficiency of the current and reduces the resistance loss through its unique shape and layout. In addition, the design of the fishhook combined with the short connection electrode can better solve the risk of hidden cracks in the string welding of the assembly. The solder strip is connected only to the top of the fishhook and passes through the middle of the fishhook, which better solves the risk of cell sheet fragmentation, hidden cracks, etc. caused by the edge of the solder strip being welded dead, and increases the yield of the assembly.

[0140] The end of the first fish-tail structure close to the interior of the solar cell is provided with a first tail pad, which has a large enough area to ensure overlap with the wiring portion, providing a stable soldering point. The presence of the first tail pad strengthens the electrical connection between the first fish-tail structure and the wiring, reduces the contact resistance, and improves the efficiency and reliability of current transmission. The length of the first tail pad ranges from 1.2 mm to 2 mm, and is preferably 1.63 mm. The width of the first tail pad ranges from 0.1 mm to 0.5 mm, and is preferably 0.3 mm. The ratio of the size of the first tail pad along the direction of the first short connecting electrode to the length of the first short connecting electrode is 1 / 5 to 1 / 10. Within this range, the electrode material can be minimized while ensuring the stability of the solder ribbon welding. A small size pad is also beneficial for reducing optical shading and improving cell efficiency.

[0141] The second fish-tail structure is also provided with a second tail pad at its end close to the interior of the solar cell. Similar to the first tail pad, the second tail pad ensures overlap with the wiring portion, providing an additional soldering point and optimizing the electrical connection between the second fish-tail structure and the wiring. For example, the projection of the second tail pad on the solar cell does not completely coincide with that of the first tail pad, in order to distribute the tensile stress of the solder ribbon on the edge of the solar cell and reduce the risk of hidden cracks.

[0142] At both ends of the front side of the cell, the first tail pad of the first fish-tail structure will overlap with the wiring portion, ensuring a stable electrical connection. This design allows current to pass through the direct connection of the tail pad and the wiring, reducing resistance loss and improving the efficiency of current transmission.

[0143] At both ends of the back side of the cell, the second tail pad of the second fish-tail structure also overlaps with the wiring portion, providing a reliable electrical connection and ensuring efficient transmission of current.

[0144] Preferably, the first connecting electrodes and the second connecting electrodes on the front and back sides correspond one-to-one, and are arranged at intervals in the first direction with respect to the first fish-tail structure and the second fish-tail structure. That is, the same wiring is connected to both the first connecting electrodes of the first solar cell and the second connecting electrodes of the second solar cell, which ensures stress balance of the same wiring between adjacent solar cells. According to the embodiments of the present application, the difference between twice the number of first connecting electrodes and the number of wirings is 2 or 4 or 6, and the number of first connecting electrodes is an even number greater than or equal to 6.

[0145] In some embodiments, the number of wirings is preferably set to a specific even number, such as 10, 14, 18, 22, 26, or 30, to meet specific symmetry requirements in conjunction with the electrode pattern. As shown in Figures 2 and 3, for the symmetry requirement of the first connecting electrode, the number of wirings must satisfy: number of wirings = (2 × number of first connecting electrodes) - 2, i.e., (2 × number of first connecting electrodes) - number of wirings = 2, and the number of first connecting electrodes is an even number. For example, when the number of first connecting electrodes is 6, the number of wirings is 10; when the number of first connecting electrodes is 8, the number of wirings is 14; when the number of first connecting electrodes is 10, the number of wirings is 18; when the number of first connecting electrodes is 12, the number of wirings is 22; when the number of first connecting electrodes is 14, the number of wirings is 26; and when the number of first connecting electrodes is 16, the number of wirings is 30. This arrangement ensures stress and tension in the edge and central regions and enhances the stability of the central region, thereby making the suppression of cell warping more significant.

[0146] Based on any of the above embodiments, according to one embodiment of this application, n wirings 15 near the center line of the solar cell are connected to the first connecting electrode 14. The number of wirings 15 can be an integer less than or equal to 6 and greater than or equal to 3. When wiring is arranged at the center line position, the n wirings near the center line include wirings located at the center line and wirings on both sides of the center line. When no wiring is arranged at the center line position, the n wirings near the center line include wirings on both sides of the center line. Compared with other wirings on the solar cell, the n wirings near the center line are closer to the center line in the first direction. By setting a specific number of wirings near the center line of the cell and connecting them to the first connecting electrode, stable welding in the central region of the cell can be ensured, cell warping can be prevented, and the assembly quality and output characteristics of the solar cell module can be guaranteed. In a preferred embodiment, the first connecting electrode connected to the n wirings near the center line is symmetrically distributed around the center line of the cell to further ensure balanced welding tension of the solar cell.

[0147] Specifically, the number of wires on a solar cell module can be either odd or even. The number of wires is equal in the left and right halves of the cell, with the center line of the cell as the boundary.

[0148] When the number of wirings is odd, the center line of the solar cell can be located on a single wiring. The wiring at the center line, along with the two wirings immediately adjacent to it, are all connected to the first connecting electrode. For example, three or five wirings 15, all connected to the first connecting electrode 14, can be provided in the central region of the solar cell 1. The center line of the cell and the centrally located wiring at least partially overlap, and the number of wirings in the left and right halves of the cell is equal. By providing wirings connected to the first connecting electrode at and immediately adjacent to the center line, the symmetry of the welding between the wirings and the first connecting electrode within the central region of the cell is ensured, thereby guaranteeing balanced welding tension.

[0149] When the number of wirings is even, no wiring is provided at the center line of the solar cell 1, and 4 or 6 wirings 15 close to the center line of the solar cell are connected to the first connecting electrode 14. The number of wirings can be set to a specific even number, such as a multiple of 4, like 8, 12, 16, 20, 24, 28, 32, and so on. In a preferred embodiment, the number of wirings is set to a multiple of 4 and greater than or equal to 20. The first connecting electrode is provided at the positions of 4 or 6 wirings close to the center line in both the left and right halves, that is, a total of 4 or 6 wirings in the central area of ​​the solar cell are connected to the first connecting electrode. With this setting, when the number of wirings is greater than 20, multiple wirings at the very center of the solar cell can form a stable weld with the first connecting electrode, effectively suppressing the warping of the central area of ​​the cell; at the same time, in conjunction with the aforementioned embodiment, the first connecting electrode is also provided at the wiring positions closest to the first and second edges of the solar cell, which can effectively suppress the warping of the edge area of ​​the cell. By simultaneously strengthening the welding pull of the central and edge areas of the solar cell, the reliability and current output performance of the solar cell module can be more effectively guaranteed.

[0150] According to embodiments of this application, this application also provides a solar cell, comprising:

[0151] Semiconductor substrate 11;

[0152] First electrodes 12 are disposed on the first surface of the semiconductor substrate 11, extending along a first direction and spaced apart in a second direction; the first direction intersects the second direction.

[0153] A plurality of first connecting electrodes 14 are disposed on the first surface of the semiconductor substrate, extending along the second direction and spaced apart along the first direction; the first connecting electrodes 14 are in contact with at least half of the number of first electrodes 12, or the extension length of the first connecting electrodes 14 in the second direction is greater than half the length of the solar cell in the second direction.

[0154] A plurality of first short connection electrodes 17 are disposed on the first surface, the first short connection electrodes 17 extend along the second direction and are disposed at opposite end regions of the first surface along the second direction, and the first short connection electrodes 17 connect 2-5 first electrodes 12 in a manner that intersects with the first electrodes 12.

[0155] The number of first connecting electrodes 14 is an even number greater than or equal to 6; the first connecting electrodes 14 and the first short connecting electrodes 17 are arranged alternately from the two ends of the first direction toward the center; in the arrangement of the first connecting electrodes 14 and the first short connecting electrodes 17, the two closest to the two ends of the solar cell along the first direction are two of the plurality of first connecting electrodes 14.

[0156] According to an embodiment of this application, the solar cell further includes:

[0157] A plurality of second connecting electrodes 16 are disposed on the second surface of the semiconductor substrate 11 and extend along the second direction and are spaced apart along the first direction; the second connecting electrodes 16 are in contact with at least half of the number of second electrodes 13, or the extension length of the second connecting electrodes 16 in the second direction is greater than half the length of the solar cell in the second direction.

[0158] Multiple second short connection electrodes 18 are disposed on the second surface, the second short connection electrodes 18 extend along the second direction and are disposed at opposite end regions of the second surface along the second direction, and the second short connection electrodes 18 are connected to 2-5 second electrodes 13 in a manner that intersects with the second electrodes.

[0159] The projections of the second connecting electrode 16 and the first connecting electrode 14 on the semiconductor substrate 11 at least partially overlap; the projections of the second short connecting electrode 18 and the first short connecting electrode 14 on the semiconductor substrate at least partially overlap.

[0160] According to an embodiment of this application, in the arrangement of the first connecting electrode 14 and the first short connecting electrode 17, there are n first connecting electrodes 14 near the center line of the semiconductor substrate 11, where n is an integer less than or equal to 6 and greater than or equal to 3.

[0161] According to an embodiment of this application, optionally, n first connection electrodes near the center line of the semiconductor substrate are symmetrically distributed with the center line as the center; or, all the first connection electrodes 14 on the first surface are symmetrically distributed with the center line as the center.

[0162] According to embodiments of this application, this application also provides a solar cell, comprising:

[0163] Semiconductor substrate 11;

[0164] First electrodes 12 are disposed on the first surface of the semiconductor substrate 11, extending along a first direction and spaced apart in a second direction; the first direction intersects the second direction.

[0165] A plurality of first connecting electrodes 14 are disposed on the first surface and extend along the second direction, and are spaced apart along the first direction;

[0166] A plurality of first tail pads 21 are disposed on the first surface, the plurality of first tail pads 21 being located in the end region in the second direction and arranged at intervals along the first direction;

[0167] The first connecting electrode 14 is in contact with at least half of the first electrodes 12, or the extension length of the first connecting electrode 14 in the second direction is greater than half the length of the solar cell in the second direction;

[0168] The number of the plurality of first connecting electrodes 14 is less than the number of the first tail pads 21; and each first connecting electrode 14 is connected to one first tail pad 21;

[0169] The semiconductor substrate 11 has a first edge 111 and a second edge 112 extending along the first direction and opposite to each other. The first tail pads 21 closest to the first edge 111 and the second edge 112 are all connected to the first connecting electrode 14. Furthermore, at least three of the first tail pads 21 near the center line of the semiconductor substrate are all connected to the first connecting electrode 14.

[0170] Preferably, all n first tail pads near the center line of the semiconductor substrate are connected to the first connecting electrode, where n is an integer less than or equal to 6 and greater than or equal to 3.

[0171] Figure 11 schematically illustrates the structure of a solar cell with an odd number of first connecting electrodes. Referring to Figure 11, when an odd number of wirings are provided on the solar cell in the solar cell module of this application embodiment, the corresponding number of first connecting electrodes on the solar cell can also be odd. For example, as shown in Figure 11, the three adjacent tail pads 21 in the central region of this solar cell are all connected to the first connecting electrode 14.

[0172] It is understood that the solar cell according to the embodiments of this application is used to prepare the solar cell module in the embodiments of this application. The features corresponding to the solar cell in the above-mentioned solar cell module embodiments can all be set in the solar cell embodiments. The technical effects of the corresponding embodiments are the same as or similar to the technical effects described in the solar cell module embodiments, and will not be repeated here.

[0173] It should be noted that the directional terms mentioned in the embodiments, such as "up," "down," "front," "back," "left," and "right," are only for reference to the directions in the accompanying drawings and are not intended to limit the scope of protection of this application. Throughout the drawings, the same elements are represented by the same or similar reference numerals. Conventional structures or constructions will be omitted when they may cause confusion in understanding this application. Furthermore, the shapes, sizes, and positional relationships of the components in the drawings do not reflect their actual size, scale, or actual positional relationships.

[0174] In the above detailed description, various features are combined together in a single embodiment to simplify this application. This approach of disclosure should not be construed as reflecting an intention that embodiments of the claimed subject matter require more features than are explicitly stated in each claim. Rather, as reflected in the appended claims, this application is in a state with fewer features than all of the disclosed individual embodiments. Therefore, the appended claims are hereby explicitly incorporated into the detailed description, with each claim representing a separate preferred embodiment of this application.

[0175] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified. The term "comprising" as used in the specification or claims is interpreted in a manner similar to the term "including," as "including" is interpreted as a conjunction in the claims. The use of any term "or" in the specification or claims is intended to mean "non-exclusive or."

[0176] The above specific embodiments further illustrate the purpose, technical solution and beneficial effects of this application. It should be understood that the above are only specific embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A solar cell module characterized by comprising: Comprising: a plurality of solar cells each including a semiconductor substrate and a first electrode provided on a first surface of the semiconductor substrate, extending in a first direction and spaced apart in a second direction; and a second electrode provided on a second surface of the semiconductor substrate, extending in the first direction and spaced apart in the second direction; the first surface being opposite to the second surface; the first direction being crossed with the second direction; a plurality of first connection electrodes provided on the first surface of the semiconductor substrate, extending in the second direction and spaced apart in the first direction; a plurality of wirings extending in the second direction, the plurality of wirings being provided to electrically connect the first electrode of a first solar cell among the plurality of solar cells to the second electrode of a second solar cell adjacent to the first solar cell; the first connection electrode being in contact with at least half the number of the first electrodes, or the first connection electrode having an extension length in the second direction greater than half the length of the solar cell in the second direction; and at least part of each of the plurality of first connection electrodes overlapping and being electrically connected with the plurality of wirings; wherein the number of the first connection electrodes is less than the number of the wirings; with the center line of the solar cell in the first direction as a boundary, the solar cell is divided into a left half region and a right half region; the left half region and the right half region have the same number of first connection electrodes, and / or the wirings close to the center line are connected with the first connection electrodes.

2. The solar cell module according to claim 1, characterized by The number of the first connection electrodes is twice greater than the number of the wirings.

3. The solar cell module according to claim 1 or 2, characterized by, The number of the wirings is an even number, and / or the number of the first connection electrodes is an even number greater than or equal to 6.

4. Solar cell module according to any of claims 1 to 3, characterized in that The difference between twice the number of the first connection electrodes and the number of the wirings is 2 or 4 or 6.

5. Solar cell module according to any of claims 1 to 4, characterized in that The two outermost wirings in the first direction at least partially cover the connection of the first connection electrodes.

6. The solar cell module according to claim 5, characterized by Along the two ends in the first direction, the wirings respectively alternately cover the connection of the first connection electrodes towards the center of the solar cell.

7. Solar cell module according to any of claims 1 to 6, characterized in that Further comprising: a plurality of first short connection electrodes provided on the first surface, the first short connection electrodes extending in the second direction and being provided at opposite end regions of the first surface in the second direction, the first short connection electrodes connecting 2-5 of the first electrodes in a manner crossed with the first electrodes, the first short connection electrodes being in contact with the wirings that are not connected with the first connection electrodes.

8. The solar cell module according to claim 7, characterized by The first connection electrodes and the first short connection electrodes are arranged in an alternating manner from the two ends of the first direction to the center respectively; among the arrangement of the first connection electrodes and the first short connection electrodes, the two closest to the two ends of the solar cell in the first direction are the two of the plurality of first connection electrodes.

9. Solar cell module according to any of claims 1 to 8, characterized in that Further comprising: A plurality of first-fish-tail structures are disposed on the first surface, extend along the second direction, and are spaced apart along the first direction; the plurality of first-fish-tail structures are located at end regions in the second direction; openings of the first-fish-tail structures face outward from the battery along the second direction; and the first-fish-tail structures are in contact with one end of the plurality of first connection electrodes.

10. The solar cell module according to claim 9, characterized by The first-fish-tail structure further comprises a first tail pad, which is disposed at an end of the first-fish-tail structure close to the inside of the solar cell, and which at least overlaps the wiring portion.

11. Solar cell module according to any of claims 1 to 10, characterized in that Further comprising: A plurality of second connection electrodes are disposed on the second surface of the semiconductor substrate, extend along the second direction, and are spaced apart along the first direction; The second connection electrodes are in contact with at least half the number of the second electrodes, or the extension length of the second connection electrodes in the second direction is greater than half the length of the solar cell in the second direction; and the wiring that is in contact with the first connection electrodes of the first solar cell is also in contact with the second connection electrodes of the second solar cell.

12. The solar cell module according to claim 11, characterized by The projection of the second connection electrodes on the semiconductor substrate at least partially overlaps the first connection electrodes.

13. The solar cell module according to any one of claims 1 to 8, characterized by, Further comprising A plurality of first tail pads are disposed on the first surface, are located at end regions in the second direction, and are spaced apart along the first direction; and the first tail pads are in contact with the wiring. The solar cell has first and second edges that extend along the second direction and are opposite to each other; The plurality of first tail pads comprise a first edge tail pad close to the first edge, a second edge tail pad close to the second edge, and intermediate tail pads between the first edge tail pad and the second edge tail pad; The distance between the first edge tail pad and the intermediate tail pad closest to the first edge tail pad is D0, and the distance between the first edge tail pad and the first edge is D2; wherein 1 < D2 / D0 < 1.6, and / or D0 and D2 are both less than 10 mm.

14. Solar cell module according to any of claims 1 to 8, characterized in that, characterized in that, Further comprising A plurality of first tail pads are disposed on the first surface, are located at end regions in the second direction, and are spaced apart along the first direction; A plurality of third tail pads are disposed on the first surface close to the end regions, and are spaced apart from the first tail pads along the second direction; At least one first small pad is disposed between the first tail pad and the third tail pad, and the width of the first small pad along the second direction is respectively less than the width of the first tail pad along the second direction, the width of the third tail pad along the second direction; and / or the length of the first small pad along the first direction is respectively less than the length of the first tail pad along the first direction, the length of the third tail pad along the first direction; The first tail pad, the third tail pad, and the small pad are respectively in contact with the wiring.

15. The solar cell module according to claim 14, characterized by The first tail pad and the third tail pad are spaced apart in the second direction by a second spacing that is greater than or equal to twice the first spacing and less than five times the first spacing; and / or, the second spacing between the first tail pad and the third tail pad is greater than or equal to 1.5 mm and less than or equal to 7 mm.

16. The solar cell module according to claim 14 or 15, characterized in that, The first small pad includes a main portion extending in the first direction and two overlapping portions formed at both ends of the main portion, and an end portion of the main portion is connected to a middle portion of the overlapping portion.

17. The solar cell module according to any one of claims 1 to 16, characterized by, The n wirings close to the center line are connected to the first connection electrode, where n is an integer less than or equal to 6 and greater than or equal to 3.

18. The solar cell module according to claim 17, characterized by The number of the plurality of wirings is an even number, and the number n of the n wirings close to the center line is 4 or 6.

19. The solar cell module of claim 17, wherein, The center line of the solar cell is provided with the wirings, and the wirings at the center line and immediately adjacent to the center line are connected to the first connection electrode.

20. The solar cell module according to any one of claims 17 to 19, characterized by, The first connection electrode connected to the n wirings is symmetrically distributed about the center line.

21. The solar cell module according to any one of claims 1 to 20, characterized by, The doped semiconductor layer of the solar cell includes a doped region and a spacing region, the spacing region is arranged between adjacent first electrodes, and the doped region is provided at the position where the wiring is connected to the first connection electrode, and the spacing region is formed at the position where the wiring is not connected to the first connection electrode.

22. A solar cell, characterized by, Comprise: a semiconductor substrate; a first electrode arranged on a first surface of the semiconductor substrate, extending in a first direction, and spaced apart in a second direction; the first direction intersects the second direction; a plurality of first connection electrodes arranged on the first surface of the semiconductor substrate, extending in the second direction, and spaced apart in the first direction; the first connection electrode is in contact with at least half the number of the first electrode, or the extension length of the first connection electrode in the second direction is greater than half the length of the solar cell in the second direction; a plurality of first short connection electrodes arranged on the first surface, the first short connection electrodes extending in the second direction, and arranged at opposite end regions of the first surface in the second direction, the first short connection electrodes connecting 2-5 first electrodes in a manner intersecting the first electrodes; the number of the first connection electrodes is an even number greater than or equal to 6; the first connection electrodes and the first short connection electrodes are arranged alternately from both ends of the first direction to the center; in the arrangement of the first connection electrodes and the first short connection electrodes, the two closest to the two ends of the semiconductor substrate in the first direction are the two of the plurality of first connection electrodes.

23. The solar cell of claim 22, wherein, Further comprise: a plurality of second connection electrodes arranged on a second surface of the semiconductor substrate, extending in the second direction, and spaced apart in the first direction; the second connection electrode is in contact with at least half the number of the second electrode, or the extension length of the second connection electrode in the second direction is greater than half the length of the solar cell in the second direction; a plurality of second short connection electrodes disposed on the second surface, the second short connection electrodes extending in the second direction and disposed at opposite end regions of the second surface in the second direction, the second short connection electrodes connecting 2-5 of the second electrodes in a manner crossing the second electrodes; a projection of the second connection electrode and the first connection electrode on the semiconductor substrate at least partially overlaps; and a projection of the second short connection electrode and the first short connection electrode on the semiconductor substrate at least partially overlaps.

24. The solar cell according to claim 22 or 23, characterized in that, In the arrangement of the first connection electrodes and the first short connection electrodes, n of the first connection electrodes are located close to a center line of the semiconductor substrate, where n is an integer less than or equal to 6 and greater than or equal to 3.

25. A solar cell, characterized by, comprising: a semiconductor substrate; first electrodes disposed on a first surface of the semiconductor substrate, extending in a first direction, and spaced apart in a second direction; the first direction intersects the second direction; a plurality of first connection electrodes disposed on the first surface, extending in the second direction, and spaced apart in the first direction; a plurality of first tail pads disposed on the first surface, the plurality of first tail pads located at end regions in the second direction and spaced apart in the first direction; the first connection electrodes are in contact with at least half of the first electrodes, or the first connection electrodes have an extension length in the second direction greater than half of a length of the solar cell in the second direction; a number of the plurality of first connection electrodes is less than a number of the first tail pads; and each of the first connection electrodes is connected to one of the first tail pads; the semiconductor substrate has a first edge and a second edge extending in the second direction and opposite to each other, the first tail pads closest to the first edge and the second edge are connected to the first connection electrodes; and at least three of the first tail pads close to a center line of the semiconductor substrate are connected to the first connection electrodes.

26. The solar cell of claim 25, wherein, n of the first tail pads close to the center line of the semiconductor substrate are connected to the first connection electrodes, where n is an integer less than or equal to 6 and greater than or equal to 3.

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