Battery string and photovoltaic module

Abstract

The utility model discloses a battery piece assembly, a battery string and a photovoltaic assembly. The battery piece assembly comprises battery pieces and a plurality of welding strips. A plurality of first grid lines and a plurality of second grid lines are arranged on the battery piece, the plurality of first grid lines and the plurality of second grid lines are arranged at intervals in a staggered manner along a first direction, the plurality of first grid lines and the plurality of second grid lines extend along a second direction, the first direction is perpendicular to the second direction, and the polarities of the first grid lines and the second grid lines are opposite; the plurality of welding strips comprise a plurality of first welding strips and a plurality of second welding strips, the plurality of first welding strips are electrically connected with the plurality of first grid lines respectively, the plurality of second welding strips are electrically connected with the plurality of second grid lines respectively, and one end of at least one of the first welding strips and the second welding strips extends out of the battery piece. The cost can be effectively reduced, the power of the battery piece is improved, and the structure of the battery piece assembly is simplified. And meanwhile, one end of at least one of the first welding strip and the second welding strip extends out of the battery piece, so that the current on the welding strip can be conveniently led out, and the adjacent battery piece can be conveniently connected.

Description

Technical Field

[0001] This utility model relates to the field of solar cell technology, and in particular to a battery string and a photovoltaic module. Background Technology

[0002] In the existing technology, the battery design has a fine grid and a main grid, and the solder strip is welded to the main grid. The current collection path is from the fine grid to the main grid and then to the solder strip. The current transmission path is long and the current loss is large. In addition, the presence of the main grid increases the cost of the slurry. Utility Model Content

[0003] The present invention aims to at least solve one of the technical problems existing in the prior art. Therefore, one objective of the present invention is to provide a battery string that can improve current collection efficiency and reduce production costs.

[0004] The second objective of this invention is to provide a photovoltaic module comprising a battery string as described in any of the above embodiments.

[0005] A battery string according to a first aspect of the present invention includes: a plurality of battery cell assemblies, each battery cell assembly including a battery cell and a plurality of solder strips; the battery cell having a plurality of first grid lines and a plurality of second grid lines arranged alternately along a first direction; the plurality of first grid lines and the plurality of second grid lines extending along a second direction; the first direction and the second direction being perpendicular; and the polarities of the first grid lines and the second grid lines being opposite; the plurality of solder strips including a plurality of first solder strips and a plurality of second solder strips; the plurality of first solder strips being electrically connected to the plurality of first grid lines respectively; the plurality of second solder strips being electrically connected to the plurality of second grid lines respectively; at least one end of the first solder strip and the second solder strip extending out of the battery cell; the battery cells of two adjacent battery cell assemblies being electrically connected by the plurality of solder strips of the adjacent battery cell assemblies; the plurality of solder strips of two adjacent battery cell assemblies being electrically connected by busbars; the busbars being provided on both sides of the battery cell along the arrangement direction of the plurality of battery cell assemblies; and the two busbars on the adjacent sides of two adjacent battery cells of two adjacent battery cell assemblies overlapping.

[0006] In some embodiments, both ends of the plurality of first solder strips are located between the two side edges of the battery cell along the second direction, and one end of the plurality of second solder strips extends out of the same side of the battery cell along the second direction.

[0007] In some embodiments, the other end of the plurality of second solder strips is located on the side of the corresponding side edge of the cell adjacent to the center of the cell.

[0008] In some embodiments, the busbar includes: a first busbar and a second busbar, the first busbar extending along the first direction, the first busbar being electrically connected to the other end of a plurality of first solder strips, and the first busbar being insulated from the other end of a plurality of second solder strips; the second busbar extending along the first direction, the second busbar being electrically connected to one end of a plurality of second solder strips.

[0009] In some embodiments, the device further includes a plurality of insulating elements, the plurality of insulating elements being disposed between the other end of the plurality of second solder strips and the first busbar.

[0010] In some embodiments, the device further includes: a plurality of soldering fluxes, wherein the plurality of soldering fluxes are respectively disposed between the same end of the plurality of first solder strips and the first busbar, and the plurality of soldering fluxes and the plurality of insulating members are located on the same side of the battery cell along the second direction.

[0011] In some embodiments, one end of the plurality of first solder strips and the plurality of second solder strips extends out of both sides of the battery cell along the second direction, and the other end of the plurality of first solder strips and the plurality of second solder strips is located between the two side edges of the battery cell along the second direction.

[0012] In some embodiments, the busbar includes two third busbars, which are respectively disposed on both sides of the battery cell along the second direction. Both third busbars extend along the first direction. The two third busbars are respectively connected to one end of a plurality of second solder strips and a plurality of first solder strips. The plurality of battery cells are overlapped by the third busbars.

[0013] In some embodiments, the cross-sectional shape of the solder strip is circular or polygonal.

[0014] In some embodiments, when the cross-sectional shape of the solder strip is circular, the diameter of the solder strip is d, and d satisfies: 0.05mm≤d≤0.2mm.

[0015] In some embodiments, the height of the first gate line and the second gate line is h, where h satisfies: 0.5μm≤h≤5μm.

[0016] In some embodiments, the width of the first busbar and the second busbar is L, and the overlap length of the first busbar and the second busbar along the arrangement direction of the plurality of battery cell assemblies is L1, wherein L and L1 satisfy: 1 / 2L≤L1≤L.

[0017] In some embodiments, the spacing between two adjacent battery cells is L2, wherein L2 satisfies: 1mm≤L2≤2mm.

[0018] A photovoltaic module according to a second aspect of the present invention includes a battery string as described in any of the above embodiments.

[0019] Additional aspects and advantages of this invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0020] The above and / or additional aspects and advantages of this utility model will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0021] Figure 1 This is a schematic diagram of the battery cell according to an embodiment of the present utility model;

[0022] Figure 2 This is a partial schematic diagram of a battery cell assembly according to an embodiment of the present utility model;

[0023] Figure 3 This is a schematic diagram of a battery cell assembly according to an embodiment of the present utility model;

[0024] Figure 4 This is a schematic diagram of a battery string according to an embodiment of the present invention.

[0025] Figure label:

[0026] 100. Solar cell assembly;

[0027] 10. Solar cell; 11. First grid line; 12. Second grid line; 13. First solar cell; 14. Second solar cell; 15. Third solar cell;

[0028] 20. Welding strip; 21. First welding strip; 22. Second welding strip;

[0029] 30. Busbar; 31. First busbar; 32. Second busbar; 33. Third busbar;

[0030] 40. Insulating components;

[0031] 50. Soldering aids;

[0032] 200, battery string;

[0033] A. First direction; B. Second direction. Detailed Implementation

[0034] The embodiments of this utility model are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Figures 1-4The present invention describes a battery cell assembly 100 according to an embodiment of the present invention. The battery cell assembly 100 includes: battery cells 10 and a plurality of solder strips 20.

[0035] Specifically, such as Figure 1 and Figure 2 As shown, the battery cell 10 is provided with a plurality of first grid lines 11 and a plurality of second grid lines 12. The plurality of first grid lines 11 and the plurality of second grid lines 12 are arranged alternately along a first direction A. The plurality of first grid lines 11 and the plurality of second grid lines 12 extend along a second direction B. The first direction A and the second direction B are perpendicular. The polarities of the first grid lines 11 and the second grid lines 12 are opposite. The plurality of solder ribbons 20 include a plurality of first solder ribbons 21 and a plurality of second solder ribbons 22. The plurality of first solder ribbons 21 are electrically connected to the plurality of first grid lines 11 respectively. The plurality of second solder ribbons 22 are electrically connected to the plurality of second grid lines 12 respectively. One end of at least one of the first solder ribbons 21 and the second solder ribbons 22 extends out of the battery cell 10.

[0036] In this embodiment, both the first grid line 11 and the second grid line 12 are sub-grid lines, and this application uses a battery cell 10 without a main grid line. The first grid line 11 and the second grid line 12, with opposite polarities, are spaced apart and alternately arranged on the battery cell 10 along a first direction A. The first grid line 11 and the second grid line 12 correspond to the first solder strip 21 and the second solder strip 22, respectively. That is, multiple first grid lines 11 are electrically connected to multiple first solder strips 21, and multiple second grid lines 12 are electrically connected to multiple second solder strips 22. The solder strip 20 extends in the same direction as the grid line and is opposite to it along the thickness direction of the battery cell 10. Each grid line can collect current on both sides of the grid line along the first direction A. At this time, for adjacent first grid lines 11 and second grid lines 12 along the first direction A, a portion of the current within the range of the battery cell 10 corresponding to the distance between the first grid line 11 and the second grid line 12 is collected by the first grid line 11, and the other portion is collected by the second grid line 12. The solder strip 20 is welded to the grid line. At least one of the first solder strips 21 and the second solder strips 22 extends from the edge of the cell 10 along the second direction B toward a direction away from the cell 10. For example, the extended first solder strip 21 or the second solder strip 22 can be used to connect two adjacent cells 10. The arrangement of the solder strips 20 parallel to the grid lines simplifies the structure of the cell assembly 100 and improves the installation efficiency of the cell assembly 100 compared to the existing arrangement of the solder strips 20 perpendicular to the grid lines.

[0037] According to an embodiment of the present invention, the battery cell assembly 100, by arranging a plurality of first grid lines 11 and a plurality of second grid lines 12 alternately along a first direction A, allows the first solder ribbon 21 and the second solder ribbon 22 to form electrical connections with the first grid lines 11 and the second grid lines 12, respectively. This shortens the current collection path of the first grid lines 11 and the second grid lines 12, increases the speed at which current is transmitted from the battery cell 10 through the first grid lines 11 and the second grid lines 12 to the first solder ribbon 21 and the second solder ribbon 22, effectively reduces costs, increases the power of the battery cell 10, and simplifies the structure of the battery cell assembly 100. Simultaneously, at least one end of the first solder ribbon 21 and the second solder ribbon 22 extends out of the battery cell 10, facilitating the extraction of current from the solder ribbon 20 and its connection with adjacent battery cells 10.

[0038] According to some embodiments of this utility model, such as Figure 2 As shown, both ends of the plurality of first solder strips 21 are located between the two edges of the battery cell 10 along the second direction B, and one end of the plurality of second solder strips 22 extends out of the same side of the battery cell 10 along the second direction B.

[0039] In this embodiment, neither end of the plurality of first solder strips 21 extends out of the battery cell 10 along the second direction B, and one end of the plurality of second solder strips 22 adjacent to the edge of the battery cell 10 extends out of the same side of the battery cell 10 along the second direction B in a direction away from the battery cell 10.

[0040] Therefore, both ends of the plurality of first solder strips 21 are located between the two edges of the battery cell 10 along the second direction B, and one end of the plurality of second solder strips 22 extends out of the same side of the battery cell 10 along the second direction B. This facilitates the current on the second solder strips 22 to be discharged from the end of the second solder strips 22 extending out of the battery cell 10. At the same time, the plurality of second solder strips 22 extending out of the battery cell 10 facilitates the connection between the battery cells 10 and the battery cells 10, effectively improving the connection efficiency.

[0041] According to some embodiments of the present invention, the other end of a plurality of second welding strips 22 is located on the side of the corresponding side edge of the battery cell 10 adjacent to the center of the battery cell 10.

[0042] That is, multiple second solder ribbons 22 extend out of one end of the battery cell 10, while the other end opposite to one end of the battery cell 10 is located inside the battery cell 10, and only one end of the multiple second solder ribbons 22 extends out of the battery cell 10. In this embodiment, the other end of the second solder ribbon 22 that does not extend out of the battery cell 10 can be flush with the end of the first solder ribbon 21 adjacent to it along the first direction A.

[0043] Therefore, the other ends of the multiple second solder strips 22 are located on the side of the corresponding side edge of the cell 10 adjacent to the center of the cell 10, which can prevent the other ends of the multiple second solder strips 22 from being connected to the end of the first solder strip 21 extending out of the cell 10 on the corresponding cell 10, thus avoiding short circuits and improving the safety and reliability of the cell assembly 100.

[0044] According to some embodiments of this utility model, such as Figure 3 As shown, the battery cell 10 further includes: a first busbar 31 and a second busbar 32. The first busbar 31 extends along a first direction A and is electrically connected to the other end of the battery cell 10 of a plurality of first solder strips 21 away from the second solder strips 22. The first busbar 31 is insulated from the other end of the battery cell 10 of the plurality of second solder strips 22 that do not extend out of the battery cell 10. The second busbar 32 extends along the first direction A and is electrically connected to the end of the battery cell 10 of a plurality of second solder strips 22 that extends out of the battery cell 10.

[0045] That is, the first solder strip 21 has a first end and a second end opposite to each other along the second direction B, and both the first end and the second end are located inside the two side edges of the battery cell 10 along the second direction B. The second solder strip 22 has a first end and a second end opposite to each other along the second direction B, with the first end of the second solder strip 22 extending out of the battery cell 10 and the second end of the second solder strip 22 located inside the edge of the battery cell 10. The first busbar 31 is disposed along the second direction B on the edge of the battery cell 10 adjacent to the second end of the second solder strip 22 and forms an electrical connection with the second end of the first solder strip 21. At the same time, the first busbar 31 is insulated from the second end of the second solder strip 22. The second busbar 32 is disposed along the second direction B on the edge of the battery cell 10 adjacent to the first end of the second solder strip 22 and forms an electrical connection with the first end of the second solder strip 22, that is, the end that extends out of the battery cell 10.

[0046] Therefore, the first busbar 31 is electrically connected to the other end of the plurality of first solder strips 21 extending away from the second solder strips 22 of the cell 10, and the second busbar 32 is electrically connected to the other end of the plurality of second solder strips 22 extending away from the cell 10. This facilitates the discharge of current from the second solder strips 22 to the second busbar 32, and simultaneously facilitates the discharge of current from the first solder strips 21 to the first busbar 31, thereby achieving current output. Furthermore, the first busbar 31 is insulated from the other end of the plurality of second solder strips 22 that does not extend out of the cell 10, which can prevent the current from the second solder strips 22 from converging into the first busbar 31 and causing a short circuit, effectively improving the safety and reliability of the cell assembly 100. In addition, the arrangement of the first busbar 31 and the second busbar 32 facilitates the overlapping between two adjacent cells 10, improves the efficiency of the cells 10 forming the cell string 200, and facilitates the connection of the cells 10.

[0047] According to some embodiments of this utility model, such as Figure 2As shown, the battery cell assembly 100 also includes a plurality of insulating members 40, which are respectively disposed between the other end of the plurality of second welding strips 22 that do not extend out of the battery cell 10 and the first busbar 31.

[0048] That is, multiple insulating elements 40 are spaced apart along the first direction A between the other end of the multiple second welding strips 22 that do not extend out of the battery cell 10 and the first busbar 31, for insulating the second welding strips 22 and the first busbar 31.

[0049] Therefore, multiple insulating components 40 are respectively disposed between the other end of the multiple second solder strips 22 that do not extend out of the battery cell 10 and the first busbar 31, which can prevent the other end of the second solder strips 22 that extend out of the battery cell 10 from forming an electrical connection with the first busbar 31, thereby preventing the current on the other end of the second solder strips 22 that extend out of the battery cell 10 from being transmitted to the first busbar 31, and preventing interference with the current collected by the first solder strips 22 on the first busbar 31 to form a short circuit.

[0050] According to some embodiments of this utility model, such as Figure 2 As shown, the battery cell assembly 100 also includes: a plurality of soldering aids 50, which are respectively disposed between the same end of a plurality of first solder strips 21 and the first busbar 31, and the plurality of soldering aids 50 and a plurality of insulating members 40 are located on the same side of the battery cell 10 along the second direction B.

[0051] That is, one end of the second solder strip 22 extends out of the battery cell 10 along the second direction B, while neither end of the first solder strip 21 extends out of the battery cell 10 along the second direction B. Multiple soldering aids 50 are spaced apart along the first direction A between the other ends of the multiple first solder strips 21 adjacent to the non-extending ends of the multiple second solder strips 22 and the first busbar 31. In this embodiment, the multiple soldering aids 50 and multiple insulating members 40 are all spaced apart along the first direction A and are all located on the side of the battery cell 10 extending away from the second solder strip 22 along the second direction B. The soldering aids 50 are located between the first busbar 31 and the first solder strips 21 to facilitate the connection between the first busbar 31 and the first solder strips 21. The first busbar 31 connects the same end of the multiple first solder strips 21 along the first direction A.

[0052] Therefore, multiple welding fluxes 50 are respectively disposed between the same end of multiple first welding strips 21 and the first busbar 31. Multiple welding fluxes 50 and multiple insulating components 40 are located on the same side of the battery cell 10 along the second direction B, which facilitates the improvement of the connection strength between the first welding strip 21 and the first busbar 31 and is beneficial to the welding of the first welding strip 21 and the first busbar 31. At the same time, the welding fluxes 50 and insulating components 40 are disposed at the end of the welding strip 20 adjacent to the first busbar 31, which facilitates the insulation of the first busbar 31 and the second welding strip 22, and the welding of the first busbar 31 and the first welding strip 21, thus optimizing the layout of the battery cell assembly 100.

[0053] According to some embodiments of this utility model, such as Figure 4 As shown, one end of the plurality of first solder strips 21 and the plurality of second solder strips 22 extends out of both sides of the battery cell 10 along the second direction B, and the other end of the plurality of first solder strips 21 and the plurality of second solder strips 22 is located between the two edges of the battery cell 10 along the second direction B.

[0054] That is, both the first solder strip 21 and the second solder strip 22 extend along the second direction B. The ends of the first solder strip 21 and the second solder strip 22 that are far apart from each other extend out of the corresponding side edge of the battery cell 10, while the two ends that are adjacent to each other are located inside the battery cell 10, that is, they do not extend out of the corresponding edge of the battery cell 10. In this embodiment, the second end of the first solder strip 21 extends out of the corresponding edge of the battery cell 10, and the first end of the second solder strip 22 extends out of the corresponding edge of the battery cell 10. The first end of the first solder strip 21 and the second end of the second solder strip 22 are respectively located inside the battery cell 10 and do not extend out of the corresponding edge of the battery cell 10 along the second direction B. The extended first and second ends can be used to overlap the busbar 30 provided on the adjacent battery cell 10 to realize the series connection between multiple battery cells 10.

[0055] Thus, one end of each of the first solder strips 21 and the second solder strips 22 extends out of both sides of the battery cell 10 along the second direction B, and the other end of each of the first solder strips 21 and the second solder strips 22 is located between the two edges of the battery cell 10 along the second direction B. There is no need to set up the welding flux 50 and the insulating component 40, which can reduce the processing cost and facilitate the connection between the multiple battery cells 10.

[0056] According to some embodiments of this utility model, such as Figure 4 As shown, the battery cell assembly 100 further includes two third busbars 33, which are respectively disposed on both sides of the battery cell 10 along the second direction B. Both third busbars 33 extend along the first direction A. The two third busbars 33 are respectively connected to one end of a plurality of second solder strips 22 extending out of the battery cell 10 and one end of a plurality of first solder strips 21 extending out of the battery cell 10.

[0057] That is, when one end of the plurality of first solder strips 21 and the plurality of second solder strips 22 extend out of the two sides of the battery cell 10 along the second direction B, the two third busbars 33 extend along the first direction A and form electrical connections with the ends of the plurality of second solder strips 22 and the ends of the plurality of first solder strips 21 extending out of the battery cell 10, respectively. When the plurality of battery cells 10 are connected in series to form a battery string 200, the grid lines on two adjacent battery cells 10 are arranged opposite to each other along the second direction B with opposite polarities and spaced apart from each other. The first end of the second solder strip 22 on one battery cell 10 overlaps with the busbar 30 on another battery cell 10 that connects the plurality of first solder strips 21. The current collected on the solder strips 20 that overlap the same busbar 30 has the same polarity.

[0058] Therefore, the two third busbars 33 are respectively connected to one end of the second solder strips 22 and the first solder strips 21 extending from the end of the cell 10. This facilitates the collection of current from the ends of the second solder strips 22 and the first solder strips 21 extending from the end of the cell 10 onto the two third busbars 33, thereby facilitating the collection of current from the cell 10. At the same time, it facilitates the connection between multiple cells 10 through the third busbars 33, thereby achieving series connection between multiple cells 10, effectively improving the working efficiency of the cell module 100 and optimizing the structure of the cell 10.

[0059] According to some embodiments of the present invention, the cross-sectional shape of the welding strip 20 is circular or polygonal.

[0060] That is, the cross-sectional shape of the first solder strip 21 that forms an electrical connection with the first grid line 11 and the second solder strip 22 that forms an electrical connection with the second grid line 12 can be circular or triangular, or the cross-sectional shape of the solder strip 20 can be partially circular and partially triangular, and can be freely selected according to the application scenario.

[0061] According to some embodiments of the present invention, when the cross-sectional shape of the welding strip 20 is circular, the diameter of the welding strip 20 is d, and d satisfies: 0.05mm≤d≤0.2mm.

[0062] When the diameter of the solder ribbon 20 is less than 0.05 mm, the small diameter may reduce the structural strength of the solder ribbon 20. Simultaneously, the contact area between the solder ribbon 20 and the first grid line 11 and the second grid line 12 is small, resulting in lower output power. When the diameter of the solder ribbon 20 is greater than 0.2 mm, the large diameter may make welding the solder ribbon 20 to the first grid line 11 and the second grid line 12 more difficult, increasing the cost of the solder ribbon 20 and potentially obstructing the surface of the solar cell 10, thus reducing the power of the solar cell 10. For example, d = 0.1 mm.

[0063] Therefore, limiting the diameter range of the solder ribbon 20 can ensure the structural strength of the solder ribbon 20, improve the output power of the solder ribbon 20, and at the same time reduce the processing difficulty between the solder ribbon 20 and the first grid line 11 and the second grid line 12, reduce the cost of the solder ribbon 20, and thus reduce the processing cost of the battery cell assembly 100.

[0064] According to some embodiments of this utility model, the height of the grid line is h, and h satisfies: 0.5μm≤h≤5μm.

[0065] When the height of the gate line is less than 0.5 μm, the gate line height is small, the cross-sectional area of ​​the gate line is small, the resistance of the gate line is large, and the output power of the gate line is low. When the height of the gate line is greater than 5 μm, the gate line height is large. Although the resistance of the gate line is small, the contact area between the gate line and the solder ribbon 20 is small, resulting in a lower output power of the solder ribbon 20. For example, h = 2 μm.

[0066] Therefore, limiting the range of grid line height can prevent excessive grid line resistance, increase grid line output power, and increase the contact area between grid line and solder ribbon 20, thereby increasing solder ribbon 20 output power and further increasing the output power of the cell module 100. This also avoids reducing the amount of paste used for setting grid lines and reduces costs.

[0067] In this application, the solder ribbon 20 is parallel to and electrically connected to the grid line, which allows for battery efficiency testing. Since this application does not have a main grid and the grid line is relatively low, testing is performed after the solder ribbon 20 is soldered to the grid line to facilitate the accuracy of the test results. This makes it easier to test the efficiency of the cell 10 structure, reduces the test resistance, and improves the accuracy of the cell 10 structure. This allows for reasonable and accurate differentiation of the cell 10, and the cell 10 is graded so that the cell 10 with smaller efficiency errors can form a cell string 200. This avoids the reduction in efficiency due to power differences between the cell 10s within the cell string 200, and helps to improve the output power of the cell 10.

[0068] According to the battery string 200 of the second aspect embodiment of the present utility model, such as Figure 4 As shown, it includes: a plurality of cell assemblies 100, wherein the cell assembly 100 is any of the cell assembly 100 in the first aspect embodiment described above, and the cells 10 of two adjacent cell assemblies 100 are electrically connected by a plurality of solder strips 20 of the two adjacent cell assemblies 100.

[0069] That is, two adjacent battery cells 10 are arranged in a corresponding manner along the second direction B, and multiple first solder strips 21 and multiple second solder strips 22 arranged in a corresponding manner along the second direction B on two adjacent battery cell assemblies 100 are electrically connected, and multiple second solder strips 22 arranged in a corresponding manner along the second direction B are electrically connected to multiple first solder strips 21.

[0070] Therefore, the cells 10 of two adjacent cell modules 100 are electrically connected through multiple solder strips 20 of the two adjacent cell modules 100, and multiple cell modules 100 can be connected in series to form a cell string 200. The connection structure of multiple cells 10 is relatively simple and the connection efficiency is high.

[0071] According to some embodiments of this utility model, such as Figure 4 As shown, multiple solder strips 20 of two adjacent battery cell modules 100 are electrically connected by busbars 30.

[0072] That is, multiple solder strips 20 extending along the second direction B of two adjacent battery cell modules 100 are electrically connected by a busbar 30 extending along the first direction A.

[0073] Therefore, the multiple solder strips 20 of two adjacent cell modules 100 are electrically connected through the busbar 30, which can improve the connection strength and reliability of the multiple solder strips 20 of two adjacent cell modules 100. At the same time, it is convenient to test the working efficiency of the battery string 200 and to classify the battery string 200.

[0074] According to some embodiments of this utility model, such as Figure 4 As shown, busbars 30 are provided on both sides of the battery cell 10 along the arrangement direction of the plurality of battery cell assemblies 100, and the two busbars 30 on the adjacent side of the two adjacent battery cells 10 of the two adjacent battery cell assemblies 100 overlap.

[0075] That is, two adjacent battery cell assemblies 100 are arranged in the second direction B, and two busbars 30 extending along the first direction A of the two adjacent battery cells 10 overlap each other to connect the two adjacent battery cell assemblies 100 in series. Thus, the overlap of the two busbars 30 on the adjacent side of the two adjacent battery cells 10 of the two adjacent battery cell assemblies 100 can optimize the overlap method of the busbars 30 of the battery string 200, reduce the series connection accuracy of the battery string 200, improve the series connection efficiency of the battery string 200, and improve the working efficiency of the battery string 200.

[0076] The current collected on the first solder strip 21 and the second solder strip 22 on two adjacent battery cells 10 has opposite polarities. In this embodiment, the plurality of battery cells 10 includes a first battery cell 13, a second battery cell 14 and a third battery cell 15 arranged along the second direction B. The first solder strip 21 and the second solder strip 22 arranged on the first battery cell 13, the second battery cell 14 and the third battery cell 15 are opposite to each other along the second direction B.

[0077] Specifically, when one end of the second solder strip 22 on each battery cell 10 extends out of the battery cell 10, the second ends of the multiple first solder strips 21 on the first battery cell 13 are connected by a first busbar 31, and the first ends of the multiple second solder strips 22 are connected by a second busbar 32. Similarly, the second ends of the multiple first solder strips 21 on the second battery cell 14 are connected by a first busbar 31, and the first ends of the multiple second solder strips 22 extending from the first battery cell 13 overlap with the first busbar 31 on the second battery cell 14. The second solder strips 22 on the first battery cell 13 and the first solder strips 21 on the second battery cell 14 are staggered and spaced apart along the second direction B. Likewise, the first ends of the multiple second solder strips 22 on the second battery cell 14 overlap with the first busbar 31 on the third battery cell 15 that connects the multiple first solder strips 21. When multiple battery cells 10 are connected, the second welding strip 22 on the first battery cell 13 and the first welding strip 21 on the second battery cell 14 are connected by a busbar 30. The first ends of the multiple second welding strips 22 on the third battery cell 15 are connected by a second busbar 32 to achieve collection and outflow.

[0078] When the ends of the first solder strip 21 and the second solder strip 22 on each battery cell 10 are far apart from each other and extend out of the edge of the battery cell 10, the second ends of the multiple first solder strips 21 provided on the first battery cell 13 are connected by the third busbar 33, the first ends of the multiple second solder strips 22 on the first battery cell 13 are connected to the second ends of the multiple first solder strips 21 provided on the second battery cell 14 by the same third busbar 33, the first ends of the multiple second solder strips 22 on the second battery cell 14 are connected to the second ends of the multiple first solder strips 21 on the third battery cell 15 by the same third busbar 33, and the first ends of the multiple second solder strips 22 provided on the third battery cell 15 are connected by the third busbar 33.

[0079] According to some embodiments of the present invention, the width of the first busbar 31 and the second busbar 32 is L, and the overlap length of the two busbars 30 along the arrangement direction of the multiple battery cell assemblies 100 is L1. L and L1 satisfy: 1 / 2L≤L1≤L.

[0080] When the overlap length of two busbars 30 along the arrangement direction of the multiple cell modules 100 is less than half the width of the first busbar 31 and the second busbar 32, the overlap length is too small, resulting in a small overlap area. This may prevent the solder ribbons 20 of adjacent cell modules 100 from being effectively electrically connected. Conversely, when the overlap length of two busbars 30 along the arrangement direction of the multiple cell modules 100 is greater than the width of the first busbar 31 and the second busbar 32, the overlap length is too large. This may cause the solder ribbons 20 of adjacent cell modules 100 to overlap, potentially leading to a short circuit. For example, L1 = 1 / 2L.

[0081] Therefore, by limiting the range of overlap lengths of the two busbars 30 along the arrangement direction of the multiple cell modules 100, the solder strips 20 of the two adjacent cell modules 100 are effectively electrically connected, while avoiding short circuits in the cell modules 100, thus improving the safety and reliability of the cell string 200.

[0082] According to some embodiments of the present invention, the distance between two adjacent battery cells 10 is L2, and L2 satisfies: 1mm≤L2≤2mm.

[0083] When the spacing between two adjacent solar cells 10 is less than 1mm, the spacing is too small, causing mutual shading between the two cells, reducing the amount of light entering and decreasing the efficiency of the solar cell string 200. When the spacing between two adjacent solar cells 10 is greater than 2mm, the spacing is too large, resulting in an excessively long current transmission path, increased resistance, and further reduced efficiency of the solar cell string 200. For example, L2 = 1.5mm.

[0084] Therefore, limiting the spacing between two adjacent solar cells 10 can prevent the shadows of two adjacent solar cells 10 from blocking each other, avoid excessively long current transmission paths, reduce current transmission losses, maximize the photoelectric conversion efficiency of the solar cell string 200, and at the same time increase the number of solar cells 10 assembled to increase power.

[0085] A photovoltaic module according to a third aspect embodiment of the present invention includes a cell assembly 100 of any one of the first aspect embodiments described above, or a cell string 200 of any one of the second aspect embodiments described above.

[0086] According to the photovoltaic module of this utility model, by adopting a cell assembly 100 with the first solder strip 21 electrically connected to the first grid line 11 and the second solder strip 22 electrically connected to the second grid line 12, and the solder strips 20 of two adjacent cell assemblies 100 electrically connected by a bus bar 30 to form a cell string 200, the structure of the photovoltaic module can be simplified, the assembly efficiency can be improved, the production cost can be reduced, and at the same time, the photoelectric conversion efficiency and reliability of the photovoltaic module can be improved.

[0087] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0088] In the description of this utility model, "first feature" and "second feature" may include one or more of the features. In the description of this utility model, "multiple" means two or more. In the description of this utility model, "above" or "below" the second feature may include direct contact between the first and second features, or contact between the first and second features through another feature between them. In the description of this utility model, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature.

[0089] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example.

[0090] Although embodiments of the present invention have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A battery string, characterized in that, include: A plurality of battery cell assemblies, each battery cell assembly comprising a battery cell and a plurality of solder strips, wherein the battery cell is provided with a plurality of first grid lines and a plurality of second grid lines, the plurality of first grid lines and the plurality of second grid lines being arranged alternately along a first direction, the plurality of first grid lines and the plurality of second grid lines extending along a second direction, the first direction and the second direction being perpendicular, and the polarities of the first grid lines and the second grid lines being opposite; the plurality of solder strips comprising a plurality of first solder strips and a plurality of second solder strips being electrically connected to a plurality of first grid lines, the plurality of second solder strips being electrically connected to a plurality of second grid lines, at least one end of the first solder strip and the second solder strip extending out of the battery cell, the battery cells of two adjacent battery cell assemblies being electrically connected by a plurality of solder strips of the two adjacent battery cell assemblies, the plurality of solder strips of the two adjacent battery cell assemblies being electrically connected by a bus bar, the battery cell being provided with a bus bar on both sides along the arrangement direction of the plurality of battery cell assemblies, and the two bus bars on the adjacent side of two adjacent battery cells of two adjacent battery cell assemblies overlapping.

2. The battery string according to claim 1, characterized in that, Both ends of the plurality of first solder strips are located between the two side edges of the battery cell along the second direction, and one end of the plurality of second solder strips extends out of the same side of the battery cell along the second direction.

3. The battery string according to claim 2, characterized in that, The other end of the plurality of second solder strips is located on the side of the corresponding side edge of the cell, near the center of the cell.

4. The battery string according to claim 3, characterized in that, The busbar includes: A first busbar extends along the first direction, is electrically connected to the other end of a plurality of first solder strips, and is insulated from the other end of a plurality of second solder strips; A second busbar extends along the first direction and is electrically connected to one end of a plurality of second solder strips.

5. The battery string according to claim 4, characterized in that, Also includes: Multiple insulating elements are respectively disposed between the other end of the multiple second welding strips and the first busbar.

6. The battery string according to claim 5, characterized in that, Also includes: Multiple soldering aids are provided, each disposed between the same end of the multiple first solder strips and the first busbar, and the multiple soldering aids and the multiple insulating components are located on the same side of the battery cell along the second direction.

7. The battery string according to claim 1, characterized in that, One end of each of the first solder strips and the second solder strips extends out of both sides of the battery cell along the second direction, and the other end of each of the first solder strips and the second solder strips is located between the two edges of the battery cell along the second direction.

8. The battery string according to claim 7, characterized in that, The busbar includes: Two third busbars are respectively disposed on both sides of the battery cell along the second direction. Both third busbars extend along the first direction. The two third busbars respectively connect one end of multiple second solder strips and multiple first solder strips. Multiple battery cells are connected to each other through the third busbars.

9. The battery string according to claim 1, characterized in that, The cross-sectional shape of the welding strip is circular or polygonal.

10. The battery string according to claim 1, characterized in that, When the cross-sectional shape of the welding strip is circular, the diameter of the welding strip is d, and d satisfies: 0.05mm≤d≤0.2mm.

11. The battery string according to any one of claims 1-10, characterized in that, The height of the first gate line and the second gate line is h, where h satisfies: 0.5μm≤h≤5μm.

12. The battery string according to claim 4, characterized in that, The width of the first busbar and the second busbar is L, and the overlap length of the first busbar and the second busbar along the arrangement direction of the plurality of battery cell assemblies is L1. The L and L1 satisfy: 1 / 2L≤L1≤L.

13. The battery string according to claim 1, characterized in that, The spacing between two adjacent battery cells is L2, and L2 satisfies: 1mm≤L2≤2mm.

14. A photovoltaic module, characterized in that, Includes the battery string according to any one of claims 1-13.

Images