Solar cells and photovoltaic modules

Abstract

The present invention discloses a solar cell and photovoltaic module. The cell comprises: a main grid line and a secondary grid line. The main grid lines are arranged parallel to each other on the front of the cell and extend along a first direction of the cell; the secondary grid lines are arranged parallel to each other and intersect perpendicularly with the main grid lines. The main grid line, which is arranged near a first edge of the cell, is arranged at a first distance of greater than or equal to 10 mm from the first edge, which is the edge of the cell extending along the first direction. The solar cell according to the present invention can reduce the risk of laminate cracking.

Description

Technical Field

[0001] The present invention relates to the technical field of photovoltaic cells, and in particular to a solar cell and a photovoltaic module. Background Art

[0002] With the development of photovoltaic cell module technology, multi-grid technology has become the current mainstream technology, and the size of cell modules is getting larger and larger. As the cell format becomes larger, it is more difficult to control the warping of the module backplane, such as the edge of double-glass glass. Therefore, cracking problems are prone to occur during lamination. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a solar cell that can reduce the risk of laminate cracking.

[0004] A second objective of the present invention is to provide a photovoltaic module.

[0005] In order to achieve the above-mentioned purpose, an embodiment of the first aspect of the present invention proposes a solar cell, which includes a main grid line, and there are multiple main grid lines, which are arranged parallel to each other on the front side of the cell and extend along the first direction of the cell; there are multiple secondary grid lines, which are arranged parallel to each other and intersect the main grid lines perpendicularly; wherein, the first distance between the main grid line arranged near the first edge of the cell and the first edge is greater than or equal to 10 mm, and the first edge is the edge of the cell extending along the first direction.

[0006] According to the solar cell of the embodiment of the present invention, by increasing the first distance between the main grid line arranged near the first edge of the cell and the first edge, that is, setting the first distance between the two to be greater than or equal to 10 mm, that is, increasing the distance between the cell and the warped portion of the backplane edge, the pressure applied to the cell by the warped portion of the backplane during lamination can be reduced, thereby reducing the risk of the cell cracking, and effectively improving the lamination cracking problem.

[0007] In some embodiments, the distances between adjacent busbars are equal. By setting the distances between the busbars to be equal, the current collection paths are balanced and the battery efficiency is improved.

[0008] In some embodiments, the distance between adjacent busbars is greater than the first distance, thereby making the distribution of the distance between adjacent busbars reasonable, facilitating current collection, and avoiding light blocking.

[0009] In some embodiments, each of the main grid lines includes: a main line portion extending along the first direction; a first harpoon portion provided at each end of the main line portion, wherein the fork end of the first harpoon portion has an opening; and a second harpoon portion provided in the middle of the main line portion, wherein the fork end of the second harpoon portion is connected to the secondary grid line. By providing openings at both ends of the main grid line, the soldering ribbon can be arranged at the openings when the soldering ribbon is installed, thereby preventing the soldering ribbon from forming an alloy with the secondary grid line and generating a bulge, thereby reducing the risk of cracks caused by the soldering bulge.

[0010] In some embodiments, the first harpoon portion includes: a first tine, a second tine located on both sides of the first tine, and a third tine; the length of the second tine and the length of the third tine are both greater than the length of the first tine, and the length of the second tine is equal to the length of the third tine; the first end of the first tine, the first end of the second tine, and the first end of the third tine are connected to the main line portion through a first electrode solder joint, and the secondary grid line between the second end of the second tine and the second end of the third tine is disconnected to form the opening. The secondary grid line between the second tine and the third tine is disconnected to form the opening, and during soldering, the tin on the soldering ribbon will not form a tin-lead alloy with the secondary grid line, reducing the risk of hidden cracks in the laminate.

[0011] In some embodiments, the second harpoon portion includes: a fourth tine, a fifth tine and a sixth tine located on both sides of the fourth tine; the length of the fifth tine and the length of the sixth tine are both greater than the length of the fourth tine, and the length of the fifth tine is equal to the length of the sixth tine; the first end of the fourth tine, the first end of the fifth tine, and the first end of the sixth tine are connected to the main line portion via a second electrode welding point, and the second end of the fifth tine and the second end of the sixth tine are connected via a secondary grid line. The fifth tine and the sixth tine are connected via the secondary grid line to facilitate current collection and avoid darkening during EL (electroluminescence) testing of the entire wafer.

[0012] In some embodiments, the number of second harpoon portions on each main line portion is two, the two second harpoon portions are arranged opposite each other, and the tine end of one of the two oppositely arranged second harpoon portions is connected to the first secondary grid line, and the tine end of the other second harpoon portion is connected to the second secondary grid line, wherein the first secondary grid line and the second secondary grid line are arranged adjacent to each other. Thus, a gap is formed between the two oppositely arranged harpoon portions, facilitating cutting between the two harpoon portions.

[0013] In some embodiments, the solar cell further comprises: a first auxiliary grid line extending along the first direction and connected to the first end of each auxiliary grid line, wherein the first auxiliary grid line has a first break between the first auxiliary grid line and the second auxiliary grid line; and a second auxiliary grid line extending along the first direction and connected to the second end of each auxiliary grid line, wherein the second auxiliary grid line has a second break between the first auxiliary grid line and the second auxiliary grid line. Thus, the whole cell can be cut along the extension direction of the auxiliary grid line at the break to cut the whole cell into half cells.

[0014] In some embodiments, the solar cell further comprises a back electrode, wherein the plurality of back electrodes are arranged parallel to each other on the back side of the cell and extend along the first direction. Each back electrode comprises a plurality of electrode segments, and each electrode segment overlaps with the projection of at least one electrode welding point on the main line portion on the back side of the cell. This ensures that the back electrode is pressed by the pressure pin during welding, thus avoiding welding defects such as cold solder joints.

[0015] In some embodiments, the size of the solar cell is 210 mm*210 mm, and the number of busbars is 12. Thus, for a cell of 210 mm*210 mm size, current collection can be ensured while avoiding large-area shading and ensuring light absorption rate.

[0016] In some embodiments, the first distance is set to 11.5 mm. Increasing the distance between the edge grid line and the edge of the cell can reduce the risk of cell cracking.

[0017] In some embodiments, the size of the solar cell is 182 mm*182 mm, and the number of busbars is 10. Thus, for a cell with a size of 182 mm*182 mm, current collection can be ensured while avoiding large-area shading and ensuring light absorption rate.

[0018] In some embodiments, the first distance is set to 11.8 mm. Increasing the distance between the edge grid line and the edge of the cell can reduce the risk of cell cracking.

[0019] In order to achieve the above-mentioned purpose, a photovoltaic module proposed in a second embodiment of the present invention includes: a cell array, wherein the cell array includes a plurality of half cells cut from the solar cell mentioned in the above embodiment.

[0020] According to an embodiment of the present invention, a photovoltaic module is constructed by using a half solar cell cut from the above embodiment. By increasing the first distance between the main grid line disposed near the first edge of the cell and the first edge, the pressure applied to the cell by the warped portion of the backsheet is reduced, thereby reducing the risk of cell cracking and effectively alleviating the problem of laminate cracking. Additional aspects and advantages of the present invention will be described in part in the following description and will become apparent from the following description or learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0022] Figure 1 is a schematic diagram of the front side of a solar cell according to one embodiment of the present invention;

[0023] Figure 2 is a schematic diagram of the front side of a solar cell according to one embodiment of the present invention;

[0024] Figure 3 is a schematic diagram of the front side of a solar cell according to one embodiment of the present invention;

[0025] Figure 4 is a schematic diagram of a first harpoon portion according to one embodiment of the present invention;

[0026] Figure 5 is a schematic diagram of a second harpoon portion according to one embodiment of the present invention;

[0027] Figure 6 is a schematic diagram of the back side of a solar cell according to one embodiment of the present invention;

[0028] Figure 7 is a schematic diagram of the back side of a solar cell according to one embodiment of the present invention;

[0029] Figure 8 FIG. 1 is a schematic diagram of the back side of a solar cell according to an embodiment of the present invention.

[0030] Reference numerals:

[0031] Solar cell 1; main grid line 10; auxiliary grid line 11; main line portion 110;

[0032] First harpoon portion 12; opening 120; first electrode solder joint 121; second electrode solder joint 122; first auxiliary gate line 123; second auxiliary gate line 124; first auxiliary gate loop 125; second auxiliary gate loop 126; first break 127; second break 128; second harpoon portion 13; first tine 14; second tine 15; third tine 16; fourth tine 17; fifth tine 18; sixth tine 19; back electrode 20; back electrode segment 21. DETAILED DESCRIPTION

[0033] The embodiments of the present invention will be described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. The embodiments of the present invention will be described in detail below.

[0034] In the embodiment, the photovoltaic module is composed of a solar cell array, a front panel, a back panel, etc. During the production and preparation process of the photovoltaic module, the module may be reworked due to some abnormality or defect in the module. For example, when the main grid line of the outermost layer of the cell is too close to the edge, the edge warping of the back panel such as double-glass glass is inevitable. During lamination, the edge of the double-glass glass is subjected to relatively large force due to the warping, and the problem of lamination cracking is prone to occur.

[0035] In order to solve the above problems, the solar cell of the embodiment of the present invention improves the main grid line 10 and the auxiliary grid line 11. Figures 1-8 A solar cell sheet according to an embodiment of the present invention is described.

[0036] like Figure 1 As shown, the solar cell 1 according to the embodiment of the present invention includes a main grid line 10 and a secondary grid line 11 .

[0037] There are multiple main grid lines 10, which are arranged parallel to each other on the front of the battery cell 1 and extend along the first direction of the battery cell 1; there are multiple auxiliary grid lines 11, which are arranged parallel to each other and intersect the main grid lines 10 perpendicularly; wherein the first distance between the main grid line 10 arranged near the first edge of the battery cell 1 and the first edge is greater than or equal to a preset length threshold, such as 10 mm, to reduce the risk of chipping, wherein the first distance is such as Figure 1 The distance shown in b in the figure; the first edge is the edge of the cell 1 extending along the first direction. If the distance between the outermost busbar 10 of the solar cell 1 and the edge is close, for example, less than 10mm, especially for double-glass modules, when the edge of the back glass is greatly warped, the pressure applied by the warped edge of the back glass to the cell 1 is relatively large during lamination, which can easily cause cracks. Therefore, in the embodiment of the present invention, the distance between the busbar 10 at the edge of the cell 1 and the edge of the cell is set to be, for example, Figure 1The distance b in the image is increased, for example, greater than or equal to 10 mm, so that the main grid line 10 at the edge is away from the warped part of the back panel edge. During lamination, the pressure applied to the cell 1 by the warped part of the back panel, such as glass, can be reduced, thereby reducing the risk of lamination cracking.

[0038] In some embodiments, the first distance is greater than or equal to 10 mm, that is, the first distance between the main grid line 10 arranged near the first edge of the battery cell 1 and the first edge is controlled to be above 10 mm, for example, the first distance is 12 mm or 14 mm or 15 mm, etc. When the glass edge is severely warped, the risk of laminate cracking can be reduced by increasing the distance between the main grid line 10 and the first edge.

[0039] According to the solar cell 1 of the embodiment of the present invention, the first distance between the main grid line 10 arranged near the first edge of the cell 1 and the first edge of the cell 1 is increased, that is, the first distance between the two is set to be greater than or equal to 10 mm, that is, the distance between the cell 1 and the warped portion of the back panel edge is increased. During lamination, the pressure applied to the edge of the cell by the warped portion of the back panel, such as glass, can be reduced, thereby reducing the risk of the cell 1 cracking, and effectively improving the lamination cracking problem.

[0040] In some embodiments, the length of the solar cell 1 is, for example, denoted as a, the first distance between the main grid line 10 close to the first edge and the first edge is b, the number of the main grid lines 10 is, for example, denoted as N, and the distance between the remaining main grid lines 10 is (a-2b) / (N-1). By evenly distributing multiple main grid lines 10, the current collection path can be balanced, thereby improving the working efficiency of the solar cell 1.

[0041] In some embodiments, as Figure 1 As shown, the first distance b is greater than or equal to 10 mm, and the distance between adjacent main grid lines 10 is greater than the first distance b. Setting the distance between adjacent main grid lines 10 to be greater than the first distance b not only facilitates current collection, but also avoids large-area shading that affects light absorption, making the distribution of the main grid lines 10 on the battery cell 1 more reasonable.

[0042] For example, Figure 2 Figure 2 is a schematic diagram of the front of a solar cell according to an embodiment of the present invention. The solar cell 1 has a size of 210 mm by 210 mm, and the number N of busbars 10 is 12. The first distance between the busbars 10 near the first edge of the cell 1 and the first edge is greater than or equal to 11.5 mm. For example, the first distance is 12 mm, 13 mm, or 14 mm. This distance keeps the edge busbars 10 away from the warped portion of the backplane edge. This reduces the pressure applied to the cell 1 by the warped portion of the glass during lamination, thereby lowering the risk of lamination cracking.

[0043] Furthermore, the distances between adjacent main grid lines 10 are set to (210-2*11.5) / (12-1), that is, the distances between adjacent main grid lines 10 are equal, and the distances between adjacent main grid lines 10 are greater than or equal to the first distance. By evenly distributing multiple main grid lines 10, the current collection path can be balanced, and the working efficiency of the solar cell 1 can be improved. The distances between the main grid lines 10 are greater than or equal to the first distance. For a cell with a size of 210mm*210mm, by setting the distances between the main grid lines 10, the layout of the main grid lines 10 on the cell 1 is more reasonable, which is convenient for collecting current and can avoid unreasonable light blocking caused by the grid lines.

[0044] For example, Figure 3 Figure 2 is a schematic diagram of the front of a solar cell according to an embodiment of the present invention. The solar cell has a size of 182 mm by 182 mm, and the number of busbars 10 is 10. A first distance between the busbars 10 near the first edge of the cell 1 and the first edge is greater than or equal to 11.8 mm, such as 12 mm, 13 mm, or 14 mm. This distance allows the edge busbars 10 to be away from the warped portion of the backplane edge. This reduces the pressure applied to the cell 1 by the warped portion of the glass during lamination, thereby lowering the risk of cracking during lamination.

[0045] The distances between the remaining main grid lines 10 are all set to (182-2*11.8) / (10-1), the distances between adjacent main grid lines 10 are equal, and the distances between the main grid lines 10 are greater than or equal to the first distance. For a battery cell with a size of 182mm*182mm, by setting the distances between the main grid lines 10, the layout of the main grid lines 10 on the battery cell 1 is more reasonable, which is convenient for collecting current and can avoid unreasonable light blocking caused by the grid lines.

[0046] In general, for solar cells 1 of different sizes, by setting the number N of main grid lines 10 and the value of the first distance between the main grid line 10 near the first edge of the cell 1 and the first edge, the design of the cell 1 is made more reasonable and the working efficiency of the cell 1 is improved.

[0047] Furthermore, in some embodiments, the structure of the main grid line 10 is improved, such as Figure 1As shown, each main grid line 10 includes a main line portion 110 extending along a first direction, and a first harpoon portion 12 is provided at both ends of the main line portion 110. The fork end of the first harpoon portion 12 has an opening 120, that is, the fork end of the first harpoon portion 12 is not connected to the auxiliary grid line 11. Therefore, when the cell 1 is welded, when a welding ribbon passes through the fork end, the welding ribbon will not form a tin-lead alloy with the auxiliary grid line 11 and bulge, thereby avoiding the risk of hidden cracks during lamination; a second harpoon portion 13 is provided in the middle of the main line portion 110, and the fork end of the second harpoon portion 13 is connected to the auxiliary grid line 11. There is no need to weld in the middle of the main line portion 110, and the fork end of the second harpoon portion 13 is connected to the auxiliary grid line 11, which facilitates current collection, avoids the darkening phenomenon during EL testing, and improves the efficiency of cell testing. Among them, by performing EL testing on the cell 1, it is possible to reasonably control the defects of photovoltaic modules caused by process parameter settings and human factors.

[0048] In some embodiments, as Figure 4 The figure shows a schematic diagram of the first harpoon portion of an embodiment of the present invention. The first harpoon portion 12 includes a first tine 14, a second tine 15 and a third tine 16 located on both sides of the first tine 14; the length of the second tine 15 and the length of the third tine 16 are both greater than the length of the first tine 14, and the length of the second tine 15 is equal to the length of the third tine 16; the first end of the first tine 14, the first end of the second tine 15 and the first end of the third tine 16 are connected to the main line portion 110 through a first electrode welding point 121, and the secondary grid line 11 between the second end of the second tine 15 and the second end of the third tine 16 is disconnected to form an opening 120. By setting the opening 120, the secondary grid line 11 is disconnected at the position of the opening 120. When the battery cell 1 is welded, a small amount of tin-lead alloy is avoided from forming between the welding strip and the position of the opening 120, and no bulge appears on the battery cell 1, reducing the risk of hidden cracks during lamination.

[0049] In some embodiments, as Figure 5 The figure shows a schematic diagram of the second harpoon portion of an embodiment of the present invention. The second harpoon portion 13 includes a fourth tine 17, a fifth tine 18 and a sixth tine 19 located on both sides of the fourth tine 17; the length of the fifth tine 18 and the length of the sixth tine 19 are both greater than the length of the fourth tine 17, and the length of the fifth tine 18 is equal to the length of the sixth tine 19; the first end of the fourth tine 17, the first end of the fifth tine 18 and the first end of the sixth tine 19 are connected to the main line portion 110 through the second electrode welding point 122, and the second end of the fifth tine 18 and the second end of the sixth tine 19 are connected through the auxiliary grid line 11. Connecting the second ends of the fifth tine 18 and the sixth tine 19 through the auxiliary grid line 11 facilitates current collection, avoids the darkening phenomenon when the battery cell 1 is tested for EL, and improves the detection efficiency of the battery cell 1.

[0050] In some embodiments, as Figure 1 and Figure 5 As shown, there are two second harpoon portions 13 on each main line portion 110, and the two second harpoon portions 13 are arranged opposite each other. The fork end of one of the two oppositely arranged second harpoon portions 13 is connected to the first secondary grid line 123, and the fork end of the other second harpoon portion 13 is connected to the second secondary grid line 124, wherein the first secondary grid line 123 and the second secondary grid line 124 are arranged adjacent to each other. This facilitates current collection and avoids the darkening phenomenon during EL testing, thereby improving the test efficiency of the battery cell 1. In addition, a gap is formed between the two oppositely arranged harpoon portions, making it easier to cut between the two harpoon portions.

[0051] In some embodiments, as Figure 1 and Figure 5 As shown, the solar cell 1 further includes a first auxiliary grid line 125 and a second auxiliary grid line 126. The first auxiliary grid line 125 extends along a first direction and is connected to the first end of each auxiliary grid line 11, wherein the first auxiliary grid line 125 has a first break 127 between the first auxiliary grid line 123 and the second auxiliary grid line 124; the second auxiliary grid line 126 extends along the first direction and is connected to the second end of each auxiliary grid line 11, wherein the second auxiliary grid line 126 has a second break 128 between the first auxiliary grid line 123 and the second auxiliary grid line 124. The first auxiliary grid line 125 is connected to the first end of the auxiliary grid line 11, and the second auxiliary grid line 126 is connected to the second end of the auxiliary grid line 11, forming a loop to facilitate current collection. In addition, a first break 127 and a second break 128 are formed between the first auxiliary grid line 123 and the second auxiliary grid line 124, and a gap is provided between the two second harpoon portions 13 arranged opposite to each other, so that cutting can be performed along the extension direction of the auxiliary grid line at the break to cut the whole component into half components.

[0052] In some embodiments, as Figure 6 , which is a schematic diagram of the back side of a solar cell according to an embodiment of the present invention. The solar cell 1 further comprises a back electrode 20, which is a plurality of back electrodes 20. The plurality of back electrodes 20 are arranged parallel to each other on the back side of the cell 1 and extend along a first direction. Each back electrode 20 comprises a plurality of electrode segments 21, and each electrode segment 21 overlaps with the projection of at least one electrode soldering point 111 on the main line portion 110 on the back side of the cell 1. For example, one electrode soldering point 111 overlaps with the projection of the back electrode segment 21 on the back side of the cell 1. Figure 1 and Figure 6As shown, one of the two electrode solder joints 111 overlaps with a back electrode segment 21. The position of the pressure needle of the welding machine is mainly designed according to the position of the electrode solder joint 111, and the position of the back electrode segment 21 is set according to the position of the front electrode solder joint 111 of the battery cell. By matching the positions of the electrode solder joint 111 and the back electrode segment 21, it is ensured that the back electrode segment 21 can be pressed by the pressure needle during the welding process, thereby avoiding the problem of cold welding during the welding process and improving the welding quality of the battery cell 1.

[0053] In some embodiments, as Figure 7 As shown, the size of the solar cell is 210mm*210mm, that is, a=210mm, and it is provided with 12 main grid lines, and the arrangement of the back electrode 20 and the back electrode segment 21 is as follows Figure 7 As shown, and Figure 8 As shown, the size of the solar cell is 182mm*182mm, that is, a=182mm, and it is provided with 10 main grid lines, and the arrangement of the back electrode 20 and the back electrode segment 21 is as follows Figure 8 shown.

[0054] In summary, according to the solar cell 1 of the embodiment of the present invention, by increasing the distance between the main grid line 10 near the edge of the cell 1 and the edge, for example, greater than or equal to a preset length threshold, the pressure applied by the edge of the back plate to the edge of the cell 1 can be reduced during lamination. In particular, for double-glass, the edge is warped. The edge main grid line 10 is set away from the edge, and the pressure applied by the warped part of the double-glass to the edge of the cell can be reduced during lamination, thereby reducing the risk of lamination cracks and effectively improving the problem of double-glass lamination cracks. In addition, the end of each main grid line 10 is set The first harpoon portion 12, the auxiliary grid line 11 at the fork end of the first harpoon portion 12 is disconnected to form an opening 120, which can avoid the welding strip and the auxiliary grid line 11 from forming an alloy and bulging when welding the welding strip, thereby reducing the phenomenon of cracks caused by welding bulges; and the fork end of the second harpoon portion 13 in the middle position of the main grid line 10 is connected through the auxiliary grid line 11, thereby avoiding the darkening phenomenon when the battery cell 1 is tested for EL; and, each electrode segment 21 of the back electrode 20 is arranged to overlap with the projection of at least one connection point 111, i.e., the welding pad, on the front side of the battery cell 1, which can reduce problems such as cold soldering.

[0055] In addition, according to the photovoltaic module of the embodiment of the present invention, the solar cell 1 of the above embodiment is adopted. By increasing the first distance between the main grid line 10 set near the first edge and the first edge, the risk of lamination cracking can be reduced and the lamination cracking problem can be improved.

[0056] Throughout this specification, reference to terms such as "one embodiment," "some embodiments," "illustrative embodiments," "example," "specific example," or "some examples" means that a specific feature, structure, material, or characteristic described in conjunction with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0057] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to the embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the claims and their equivalents.

Claims

1. A solar cell, characterized in that: The size of one side of the solar cell is 182 mm or 210 mm, and the solar cell comprises: A main grid line, wherein the main grid lines are multiple, and the multiple main grid lines are arranged parallel to each other on the front of the battery cell and extend along the first direction of the battery cell, and each main grid line includes: a main line portion extending along the first direction; a first harpoon portion is respectively provided at both ends of the main line portion, the fork end of the first harpoon portion has an opening, and the fork end of the first harpoon portion is not connected to the auxiliary grid line; a second harpoon portion is provided in the middle of the main line portion, and the fork end of the second harpoon portion is connected to the auxiliary grid line; Auxiliary grid lines, there are multiple auxiliary grid lines, and the multiple auxiliary grid lines are arranged parallel to each other and intersect the main grid lines perpendicularly; wherein, the first distance between the main grid line arranged near the first edge of the solar cell and the first edge is greater than or equal to 10 mm and less than or equal to 15 mm, the first edge is the edge of the solar cell extending along the first direction, and the distance between the remaining main grid lines is (a-2b) / (N-1), where a is the length of the solar cell, b is the first distance between the main grid line 10 near the first edge and the first edge, and N is the number of the main grid lines.

2. The solar cell according to claim 1, characterized in that: The distances between adjacent main grid lines are equal.

3. The solar cell according to claim 1, wherein: The distance between adjacent main grid lines is greater than the first distance.

4. The solar cell according to claim 1, wherein: The first harpoon portion comprises: a first tine, a second tine and a third tine located on either side of the first tine; The length of the second tine and the length of the third tine are both greater than the length of the first tine, and the length of the second tine is equal to the length of the third tine; The first end of the first fork tine, the first end of the second fork tine and the first end of the third fork tine are connected to the main line portion through a first electrode welding point, and the secondary grid line between the second end of the second fork tine and the second end of the third fork tine is disconnected to form the opening.

5. The solar cell according to claim 1, wherein: The second harpoon portion comprises: a fourth tine, a fifth tine and a sixth tine located on both sides of the fourth tine; The length of the fifth tine and the length of the sixth tine are both greater than the length of the fourth tine, and the length of the fifth tine is equal to the length of the sixth tine; The first end of the fourth tine, the first end of the fifth tine and the first end of the sixth tine are connected to the main line portion through a second electrode welding point, and the second end of the fifth tine and the second end of the sixth tine are connected through a secondary gate line.

6. The solar cell according to claim 5, characterized in that: The number of the second harpoon parts on each of the main line parts is two, and the two second harpoon parts are arranged opposite to each other, and the fork end of one of the two oppositely arranged second harpoon parts is connected to the first secondary grid line, and the fork end of the other second harpoon part is connected to the second secondary grid line, wherein the first secondary grid line and the second secondary grid line are arranged adjacent to each other.

7. The solar cell according to claim 6, characterized in that: The solar cell further comprises: a first auxiliary gate loop extending along the first direction and connected to the first end of each auxiliary gate line, wherein the first auxiliary gate loop has a first break between the first auxiliary gate line and the second auxiliary gate line; A second auxiliary gate loop extends along the first direction and is connected to the second end of each auxiliary gate line, wherein the second auxiliary gate loop has a second break between the first auxiliary gate line and the second auxiliary gate line.

8. The solar cell according to claim 1, wherein: The solar cell further comprises: a back electrode, wherein the back electrodes are multiple and are arranged parallel to each other on the back side of the battery cell and extend along the first direction; Each of the back electrodes includes a plurality of electrode segments, and each of the electrode segments overlaps with a projection of at least one electrode welding point on the main line portion on the back side of the battery cell.

9. The solar cell according to any one of claims 1 to 8, characterized in that: The size of the solar cell is 210 mm*210 mm, and the number of main grid lines is 12.

10. The solar cell according to claim 9, characterized in that: The value of the first distance is 11.5 mm.

11. The solar cell according to any one of claims 1 to 8, characterized in that: The size of the solar cell is 182mm*182mm, and the number of main grid lines is 10.

12. The solar cell according to claim 11, wherein: The value of the first distance is 11.8 mm.

13. A photovoltaic module, characterized in that: The solar cell array comprises a plurality of half cells cut from the solar cell according to any one of claims 1 to 12.

Images