Battery sheet and photovoltaic module

Abstract

The application discloses a battery piece and a photovoltaic module, and belongs to the technical field of solar cells. The battery piece comprises a battery piece body, an electrode structure arranged on the surface of the battery piece body, the electrode structure comprising first grid lines and second grid lines, the first grid lines extending along a first direction, a plurality of the first grid lines being arranged at intervals along a second direction perpendicular to the first direction, the second grid lines extending along the second direction, a plurality of the second grid lines being arranged at intervals along the first direction, and the first grid lines and the second grid lines being connected in the same conductive polarity; and a welding pad arranged on the surface of the battery piece body, the welding pad being used for being connected with a welding strip, and the welding strip being used for leading out the current collected by the electrode structure; wherein the line width of the first grid lines is smaller than the line width of the second grid lines, and at least one welding pad is spaced apart from any second grid line. The battery piece can make the current transmission in the second grid lines not be affected by the resistivity variation of the welding pad, and can improve the battery performance and use stability.

Description

Technical Field

[0001] This application belongs to the field of solar cell technology, and particularly relates to a solar cell and a photovoltaic module. Background Technology

[0002] The welding ribbon can collect and conduct the current generated in the battery cell to the external circuit, and its welding quality has a direct impact on the battery's efficiency and reliability.

[0003] During the soldering process, solder paste is usually used as the solder. However, the metals (such as silver and gold) in the metal paste printed and sintered structure of the main grid and pads (also known as PADs) on the solar cell are prone to interact with the solder paste. For example, silver can partially dissolve or diffuse into the solder. This phenomenon is usually called the "silver eating" reaction, which will cause the resistance of the solder paste soldering area to increase and affect the current collection efficiency. Utility Model Content

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a solar cell and photovoltaic module that can improve cell performance and operational stability.

[0005] In a first aspect, this application provides a battery cell, comprising:

[0006] The battery cell itself;

[0007] An electrode structure is disposed on the surface of the battery cell body. The electrode structure includes a first grid line and a second grid line. The first grid line extends along a first direction. Multiple first grid lines are spaced apart along a second direction perpendicular to the first direction. The second grid line extends along the second direction. Multiple second grid lines are spaced apart along the first direction. The first grid line and the second grid line with the same conductive polarity are connected. The first direction and the second direction are parallel to the plane in which the battery cell body is located.

[0008] A solder pad is provided on the surface of the battery cell body. The solder pad is used to connect with a solder strip, which is used to conduct the current collected by the electrode structure.

[0009] Wherein, the line width of the first gate line is smaller than the line width of the second gate line, and at least one of the pads is spaced apart from any of the second gate lines.

[0010] According to the battery cell provided in the embodiments of this application, by separating the pads from the second grid lines, the battery cell can ensure that the current transmission in the second grid lines is not affected by the resistivity change of the pads, thereby improving battery performance and usage stability.

[0011] According to one embodiment of this application, any of the pads is spaced apart from any of the second gate lines.

[0012] According to one embodiment of this application, any of the pads is also spaced apart from any of the first gate lines.

[0013] According to one embodiment of this application, the battery cell body has two first sides disposed opposite to each other along the second direction;

[0014] The distance between the pad adjacent to the first side and the first side is 5mm-10mm.

[0015] According to one embodiment of this application, the battery cell body has two first sides disposed opposite to each other along the second direction, the battery cell body is provided with an edge region where the first sides are located and a central region located between the edge regions along the second direction, and the second grid line is located at least in the edge region where the first sides are located.

[0016] According to one embodiment of this application, the distance between the pad adjacent to the first side and the second gate line located in the edge region where the first side is located is 0.1mm-0.9mm.

[0017] According to one embodiment of this application, the pad adjacent to the first side is disposed between the first critical gate line and the second critical gate line, wherein the first critical gate line and the second critical gate line are first gate lines with the same conductivity.

[0018] Wherein, the first critical gate line is the first gate line that intersects with the second gate line located in the edge region and is the shortest distance from the center region along the second direction; the second critical gate line is located at the position of the first critical gate line along the second direction toward the center region, and the second critical gate line and the first critical gate line are separated by N first gate lines with the same conductivity, 0≤N≤5.

[0019] According to one embodiment of this application, N = 0.

[0020] According to one embodiment of this application, the edge region and the center region are provided with the second grid line, or the edge region is provided with the second grid line.

[0021] According to one embodiment of this application, the edge region and the center region are provided with the second grid line, or only the edge region is provided with the second grid line.

[0022] According to one embodiment of this application, the density of welding points in the central region of the solder strip is greater than the density of welding points in the edge region, and the welding points are used to connect the solder strip and the battery cell.

[0023] According to one embodiment of this application, the first gate line has a thickened section, and at least one pair of adjacent thickened sections along the second direction are not provided with pads.

[0024] Secondly, this application provides a photovoltaic module, which includes:

[0025] At least one battery cell as described in the first aspect above.

[0026] According to the photovoltaic module provided in the embodiments of this application, by separating the pads from the second grid line, that is, the pads still provide connection points for the solder strips but are not electrically connected to the second grid line, the current transmission in the second grid line can be made unaffected by the resistivity change of the pads. In actual use, this can improve the performance and stability of the photovoltaic module.

[0027] Additional aspects and advantages of this application 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 this application. Attached Figure Description

[0028] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, in which:

[0029] Figure 1 This is a schematic diagram of the structure of the battery cell provided in the embodiments of this application;

[0030] Figure 2 This is one of the partial schematic diagrams of the battery cell provided in the embodiments of this application;

[0031] Figure 3 This is a second partial schematic diagram of the battery cell provided in the embodiments of this application;

[0032] Figure 4 This is a third partial schematic diagram of the battery cell provided in the embodiments of this application;

[0033] Figure 5 yes Figure 2 A magnified view of a section at point A1;

[0034] Figure 6 This is the fourth partial schematic diagram of the battery cell provided in the embodiments of this application.

[0035] Figure label:

[0036] The battery cell body is 100, the first side is 110, the edge area is 120, and the center area is 130.

[0037] First gate line 210, thickened section 211, second gate line 220, pad 230. Detailed Implementation

[0038] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0039] The solar cells and photovoltaic modules provided in this application are described below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0040] This application provides a battery cell that allows current transmission in the second grid line 220 to be unaffected by changes in the resistivity of the pad 230, thereby improving battery performance and operational stability.

[0041] like Figure 2 As shown, the solar cell includes: a solar cell body 100, an electrode structure, and a solder pad 230.

[0042] The solar cell body 100 may include a silicon substrate portion and can generate photocurrent.

[0043] The electrode structure is a conductive component on the cell body 100 used to collect and transmit current. It is usually made by printing metal paste such as silver paste or silver-aluminum paste onto the cell body 100 and then undergoing processes such as drying, sintering, photoinjection or electroinjection.

[0044] The solder pad 230 is disposed on the surface of the cell body 100. The solder pad 230 is used to solder with the solder strip, and a stable connection between the cell body 100 and the solder strip is achieved through the solder pad 230.

[0045] It is understandable that electrode structures and pads 230 can be provided on both sides of the cell body 100, or electrode structures and pads 230 can be provided on only one side of the cell body 100. The specific arrangement scheme is determined according to the type of cell.

[0046] For example, for emitter and back passivation (PERC) cells, oxide passivation contact (TOPCon) cells, and intrinsic thin-film heterojunction (HJT) cells, electrode structures and pads 230 are provided on both sides of the cell.

[0047] For example, for back contact (BC) cells, including but not limited to composite passivated back contact (HPBC) cells, heterojunction back contact (HBC) cells, and TOPCon back contact (TBC) cells, one side of the cell is provided with an electrode structure and a pad 230, while the other side is not provided with an electrode structure and a pad 230.

[0048] In this embodiment, the electrode structure is disposed on the surface of the battery cell body 100, including a first grid line 210 and a second grid line 220. The first grid line 210 extends along a first direction, and multiple first grid lines 210 are spaced apart along a second direction perpendicular to the first direction.

[0049] The second gate line 220 extends along the second direction, and multiple second gate lines 220 are spaced apart along the first direction. The first gate line 210 and the second gate line 220 with the same conductive polarity are connected.

[0050] In this embodiment, the linewidth of the first gate line 210 is smaller than the linewidth of the second gate line 220.

[0051] The first grid line 210 can be referred to as a fine grid. The cell body 100 is provided with multiple first grid lines 210, which uniformly cover the surface of the cell body 100. The first grid lines 210 extend along a first direction, and the multiple first grid lines 210 are arranged at intervals along a second direction to collect the photocurrent generated in the cell body 100.

[0052] The second grid line 220 can be referred to as the main grid. The cell body 100 is provided with multiple second grid lines 220, which are connected to the first grid line 210 with the same conductive polarity. The second grid lines 220 extend along the second direction, and multiple second grid lines 220 are arranged at intervals along the first direction to collect the photogenerated current collected in the fine grid.

[0053] Understandably, the second gate line 220 is used to collect the current in the first gate line 210. The line width of the second gate line 220 is greater than that of the first gate line 210, which can reduce the resistance loss when collecting current.

[0054] In this embodiment, the first direction and the second direction are parallel to the plane in which the battery cell body 100 is located.

[0055] In actual implementation, such as Figure 1 As shown, the first direction can be left and right, i.e., the R1 direction, and the second direction can be up and down, i.e., the R2 direction.

[0056] In this embodiment, the solder ribbon is used to draw out the current collected by the electrode structure, and the solder pad 230 is spaced apart from the second gate line 220.

[0057] Understandably, the solder ribbon is a key conductive material in photovoltaic modules that connects multiple solar cells, collects and leads out the current from the cells, and can be made of metal.

[0058] For example, solder strips can be made of tin-plated copper strips, which have good electrical conductivity and corrosion resistance.

[0059] The solder ribbon can be connected to the electrode structure and solder pad 230 in the solar cell to connect the solar cells in series or in parallel to form a photovoltaic module.

[0060] In practice, solder can be used to firmly solder the solder strip to the cell, or solder paste can be used as solder. The solder paste is applied to the pad 230 and part of the grid lines to achieve the connection between the cell body 100 and the solder strip.

[0061] In this embodiment, such as Figure 2 As shown, by separating at least one pad 230 from any second gate line 220, i.e., the pad 230 is not electrically connected to the second gate line 220, and when a "silver-eating" reaction occurs at the pad 230, causing its resistivity to increase, the impact of the increase in the resistivity of the pad 230 on the conductivity of the second gate line 220 can be reduced, thereby making the battery performance and efficiency more stable.

[0062] In this embodiment, the inventors discovered that compared to electrode structures such as the first gate line 210 and the second gate line 220, the amount of solder paste and silver paste used at the pad 230 is greater. During the soldering process, when the solder paste is misaligned, excessive, or the area of ​​the pad 230 is too small, the solder paste and silver paste at the pad 230 are more prone to interfacial reaction, i.e., "silver-eating" reaction. This reaction causes the silver element on the surface of the pad 230 to be gradually eroded, resulting in a significant increase in the resistivity of the pad 230 and affecting its conductivity. The pad 230 is usually electrically connected to the gate line. Among the gate lines connected to the pad 230, the second gate line 220 is responsible for collecting the current in the first gate line 210 and conducting it to the solder ribbon. The conductivity of the second gate line 220 affects the current collection in the surrounding area, which is crucial to battery performance. The reduction in the conductivity of the pad 230 will adversely affect the process of the second gate line 220 collecting and conducting current, thereby affecting battery performance and stability.

[0063] In this embodiment, the battery cell separates the pad 230 from the second grid line 220. That is, the pad 230 is still soldered to the solder ribbon, but is not electrically connected to the second grid line 220. This ensures that the increase in resistivity of the pad 230 will not affect the current transmission in the second grid line 220. This can provide a stable connection between the solder ribbon and the battery cell while reducing the impact of the "silver-eating" reaction that is prone to occur at the pad 230 on the conductivity of the second grid line 220, thereby improving battery performance and stability.

[0064] According to the battery cell provided in the embodiments of this application, by separating the pad 230 from the second grid line 220, that is, the pad 230 still provides connection points for the solder ribbon, but is not electrically connected to the second grid line 220, the current transmission in the second grid line 220 can be prevented from being affected by the resistivity change of the pad 230. In actual use, this can improve battery performance and stability.

[0065] In some embodiments, any pad 230 is spaced apart from any second gate line 220.

[0066] In this embodiment, all pads 230 in the cell 100 are spaced apart from the second gate line 220, which can further reduce the impact of resistivity changes of the pads 230 on the current transmission of the second gate line 220.

[0067] In some embodiments, such as Figure 2 As shown, any pad 230 is also spaced apart from any first gate line 210.

[0068] It is understandable that a "silver-eating" reaction is likely to occur at pad 230. Although the current in the first gate line 210 is less than that in the second gate line 220, and the impact on the "silver-eating" reaction is correspondingly smaller, the electrical connection between the first gate line 210 and the pad 230 will still have a certain adverse effect on battery performance and usage stability.

[0069] In this embodiment, in addition to separating the pad 230 from the second grid line 220, the pad 230 can also be separated from the first grid line 210. That is, the pad 230 does not participate in the current collection and output in the cell, but only provides the welding point between the solder ribbon and the cell. This can further reduce the adverse effects of the "silver-eating" reaction that is prone to occur at the pad 230 on the battery performance and stability.

[0070] It should be noted that if the first grid line 210 is too long, it will increase the abnormalities in the grid line printing process, such as false printing and broken grids. Moreover, when the first grid line 210 is abnormal, the affected area is too large, which is not conducive to improving the photoelectric performance of the solar cell.

[0071] In some embodiments, the first gate line 210 has a break, that is, a long first gate line 210 is optimized into multiple shorter first gate lines 210, which can reduce the impact range when the first gate line 210 malfunctions.

[0072] Furthermore, the break point of the first grid line 210 can also accommodate the solder pad 230 that is not electrically connected to the grid line, thereby improving the space utilization of the solar cell.

[0073] In some embodiments, the spacing of the first gate line 210 breaks is d1. When the first gate line 210 breaks and a pad 230 is provided at the break point of the first gate line 210, 1.5mm≤d1≤3mm; when the first gate line 210 breaks and no pad 230 is provided at the break point of the first gate line 210, 0.1mm≤d1≤2mm.

[0074] It is understandable that there is a suitable range for the spacing of the first grid line 210. If the spacing of the first grid line 210 is too large, it will affect the current collection and reduce the photoelectric performance of the photovoltaic module. If the spacing of the first grid line 210 is too small, it will increase the additional cost and will not be able to maintain the distance from the pad 230.

[0075] In this embodiment, the spacing of the first gate line 210 break is d1. When there is no pad 230 at the break point, 0.1mm≤d1≤2mm; when there is a pad 230 at the break point, 1.5mm≤d1≤3mm.

[0076] The spacing of the first grid line 210 can be flexibly adjusted according to the setting of the pad 230. In both cases where the pad 230 is present and where the pad 230 is not present, the spacing of the breaks can be kept within a suitable range, so that the photoelectric performance of the battery is not affected.

[0077] In some embodiments, such as Figure 1 As shown, the battery cell body 100 has two first sides 110 arranged opposite each other along a second direction; as Figure 3 As shown, the distance between the pad 230 adjacent to the first side 110 and the first side 110 is 5mm-10mm.

[0078] In actual implementation, the two first edges 110 can be the two edges of the solar cell along the second direction, for example, as shown in the example. Figure 1 As shown, if the second direction is the vertical direction of the battery cell, then the first side 110 is the top and bottom edges of the battery cell.

[0079] Understandably, the pad 230 adjacent to the first side 110 is the pad 230 closest to the edge of the cell along the second direction. During the handling of the cell and the module composed of the cell, the solder strip at the edge is subjected to greater stress. If the distance between the pad 230 adjacent to the first side 110 and the first side 110 is too large, the solder strip at the edge of the cell will not be tightly bonded and will be easily pulled off, thus affecting the photovoltaic performance of the cell and the module. At the same time, if the pad 230 is too close to the first side 110 of the cell, that is, if the distance between the pad 230 adjacent to the first side 110 and the first side 110 is too small, the force on the edge of the cell will be immediately applied to the pad 230, which will also easily cause the solder strip to be pulled off, or even cause the cell to crack.

[0080] In this embodiment, the distance between the pad 230 adjacent to the first side 110 and the first side 110 is ( Figure 3In the context of d2), the distance between the pad 230 and the edge of the cell is within a suitable range. This provides a stable and tight connection between the edge of the cell and the solder ribbon, reducing the probability of the solder ribbon being pulled off during handling or use. It also provides a certain buffer space for the pad 230, so that the force on the edge of the cell will not be immediately applied to the pad 230, thus reducing the probability of cell cracking.

[0081] In actual implementation, the range of distances between the pads 230 adjacent to the first side 110 and the first side 110 can be set according to the type of battery cell and its specific structure.

[0082] In this embodiment, the distance can be 5mm-10mm, that is, the distance from the edge of the battery cell to the pad 230 closest to the edge of the battery cell along the second direction is 5mm-10mm, which can effectively reduce the probability of battery cell cracking and the probability of the solder ribbon being pulled off during handling or use.

[0083] In some embodiments, such as Figure 1 As shown, the battery cell body 100 is provided with an edge region 120 where the first side 110 is located and a central region 130 located between the edge region 120 along the second direction.

[0084] It is understandable that the battery cell body 100 has two first sides 110, and the battery cell body 100 also has two edge regions 120 along the second direction. The area between these two edge regions 120 is the central region 130. For example, as shown in the figure... Figure 1 As shown, the battery cell body 100 has two first edges 110, one above the other. From top to bottom, the battery cell body 100 consists of an edge region 120, a central region 130, and an edge region 120.

[0085] In practice, the boundary line dividing the edge region 120 and the central region 130 can be a physical electrode structure (e.g., near a grid line on the edge) or a virtual boundary line (e.g., at a position 10 centimeters away from a side of the cell body 100).

[0086] Specifically, in this embodiment, the boundary line dividing the edge region 120 and the central region 130 is a virtual dividing line, such as... Figure 2 As shown, a pad 230 is located in the second direction R2 that is closest to the edge of the cell. The boundary line dividing the edge region 120 and the center region 130 is located between the first gate line 210, which is adjacent to the pad 230 and close to the edge of the cell, and the pad 230.

[0087] It should be noted that in other embodiments, the boundary line dividing the edge region 120 and the center region 130 can also be a broken line. For example, the boundary line is located between the pad 230 corresponding to each solder strip, in the second direction R2, closest to the edge of the cell, and the first grid line 210 that is adjacent to the pad 230 and close to the edge of the cell.

[0088] In actual implementation, the specific sizes of the edge region 120 and the central region 130 can be adjusted according to the size of the solar cell.

[0089] In some embodiments, the density of welding points in the central region 130 of the solder ribbon is greater than the density of welding points in the edge region 120, and the welding points are used to connect the solder ribbon and the battery cell 100.

[0090] In this embodiment, the solder ribbon is laid on the battery body along the first direction, soldered to the solder pad 230, and soldered to a portion of the first grid line 210 with the same conductive polarity. The position of the soldering is the solder point.

[0091] Understandably, the density of weld points is used to characterize the number of weld points in a fixed area of ​​a solar cell, that is, the number of weld points per unit length of solder strip. The higher the density, the more weld points there are.

[0092] By reducing the number of welding points in the edge region 120, making the welding point density in the edge region 120 less than that in the central region 130, stress concentration at the edge of the solar cell can be reduced, the probability of cell cracking can be lowered, and the long-term stability of the photovoltaic module can be increased.

[0093] In some embodiments, the cell body 100 has two first sides 110 disposed opposite each other along a second direction, and the second grid line 220 is located at least in the edge region 120 where the first sides 110 are located.

[0094] In this embodiment, the density of welding points in the edge region 120 is relatively low, such as Figure 2 As shown, the second grid line 220 is provided at least in the edge region 120 where the two first sides 110 are located. It can collect the current in the first grid line 210 located in the edge region 120 and not directly connected through the solder point and solder strip, thereby improving battery efficiency.

[0095] In some embodiments, the edge region 120 and the center region 130 are provided with the second gate line 220, or only the edge region 120 is provided with the second gate line 220.

[0096] Among them, such as Figure 4As shown, second grid lines 220 are arranged in both the edge region 120 and the center region 130, that is, the battery cell has a main grid structure. The second grid lines 220 uniformly cover the battery cell body 100 and collect the current in the first grid line 210.

[0097] like Figure 2 As shown, a second grid line 220 is arranged in the edge region 120, and no second grid line 220 is provided in the central region 130. That is, the cell has a gridless structure. The second grid line 220 only covers the edge region 120 in the cell body 100, and collects the current of the first grid line 210 in the edge region 120. The current of the first grid line 210 in the central region 130 is directly led to the solder ribbon through the welding point.

[0098] In some embodiments, such as Figure 5 As shown, the distance between the pad 230 adjacent to the first side 110 and the second gate line 220 located in the edge region 120 where the first side 110 is located is 0.1mm-0.9mm.

[0099] It is understandable that for the second gate line 220 and pad 230 soldered to the same solder strip, such as Figure 2 As shown, the pad 230 is located in the extension direction of the second gate line 220, and the second gate line 220 has two endpoints. The distance between the pad 230 and the second gate line 220 is the distance between the pad 230 and the closer endpoint of the second gate line 220.

[0100] For example, such as Figure 5 As shown, the pad 230 adjacent to the first side 110 is located below the second gate line 220 in the edge region 120 where the first side 110 is located. The distance between the pad 230 and the second gate line 220 is the distance from the pad 230 to the lower end point of the second gate line 220.

[0101] It is understandable that the second grid line 220 located in the edge region 120 of the first side 110 will be subjected to greater forces during the handling and use of the solar cells and their modules. Compared with the connection with the first grid line 210, if the connection between the solder ribbon and the second grid line 220 is pulled off by the force, it will have a more serious impact on the solar cells and their modules.

[0102] If the distance between the pad 230 adjacent to the first side 110 and the second gate line 220 located in the edge region 120 of the first side 110 is too large, the solder strip at the second gate line 220 will directly bear the force of the edge region 120, increasing the risk that the connection between the solder strip and the second gate line 220 will be pulled off by the force.

[0103] In this embodiment, the distance between the pad 230 adjacent to the first side 110, i.e., the pad 230 closest to the edge of the cell along the second direction, and the second gate line 220 located in the edge region 120 where the first side 110 is located ( Figure 5 The d3) is between 0.1mm and 0.9mm, so that the pad 230 is close to the second grid line 220 located in the edge region 120 where the first side 110 is located. During the handling and use of the cell and its components, the pad 230 can share the force with the second grid line 220, enhance the connection between the cell and the solder ribbon in the edge region 120 where the first side 110 is located, and reduce the risk of the connection between the solder ribbon and the second grid line 220 being pulled off by the force.

[0104] Understandably, this distance can be flexibly adjusted depending on the type and specific structure of the solar cells.

[0105] In some embodiments, the pad 230 adjacent to the first side 110 is disposed between the first critical gate line and the second critical gate line, wherein the first critical gate line and the second critical gate line are first gate lines 210 with the same conductivity polarity.

[0106] In this embodiment, the first critical gate line is the first gate line 210 that intersects with the second gate line 220 located in the edge region 120 and is the shortest distance from the center region 130 along the second direction; the second critical gate line is located at the position of the first critical gate line towards the center region 130 along the second direction.

[0107] For example, in Figure 4 As shown, the second direction is the up-down direction, and the direction along the second direction toward the central region 130 is the downward direction. The closer the first grid line 210 is to the bottom, the shorter the distance from the central region 130. The first critical grid line is the lowest first grid line 210 among all the first grid lines 210 that intersect with the second grid line 220 located in the edge region 120, and the second critical grid line is located below this grid line.

[0108] In this embodiment, the second critical gate line and the first critical gate line are separated by N first gate lines 210 with the same conductivity polarity, where 0≤N≤5.

[0109] It is understandable that the pad 230 adjacent to the first side 110 is located between the second critical gate line and the first critical gate line. By controlling the number of the first gate line 210 between the second critical gate line and the first critical gate line, satisfying 0≤N≤5, the pad 230 adjacent to the first side 110 can be made closer to the end of the second gate line 220.

[0110] In some embodiments, N = 0. In this embodiment, N can be 0, that is, the first grid line 210 closest to the first critical grid line in the direction along the second direction toward the central region 130 is set as the second critical grid line. This allows the pads 230 adjacent to the first side 110 to be close to the second grid line 220. During the handling and use of the battery cell and its components, the force can be shared with the second grid line 220, strengthening the connection between the battery cell and the solder ribbon in the edge region 120 where the first side 110 is located, thereby reducing the risk of the connection between the solder ribbon and the second grid line 220 being pulled off by the force. In some embodiments, such as Figure 6 As shown, the first grid line 210 has a thickened section 211.

[0111] In this embodiment, the first grid line 210 can be locally thickened. The thickened section 211 can improve current collection efficiency, enhance mechanical reliability, and reduce the probability of grid line breakage.

[0112] It is understandable that during the soldering process of pad 230 adjacent to the thickened segment 211, the solder paste at pad 230 is likely to be soldered to the vicinity of the thickened segment 211. The closer pad 230 is to the thickened segment 211, the greater the possibility of electrical connection with the thickened segment 211 after soldering offset.

[0113] In this embodiment, such as Figure 6 As shown, at least one pair of adjacent thickened segments along the second direction are not provided with the pads, which can reduce the possibility of electrical connection between the thickened segment 211 after soldering offset.

[0114] This application also provides a photovoltaic module.

[0115] The photovoltaic module includes at least one solar cell as described above.

[0116] In this embodiment, multiple battery cells can be connected in series or in parallel via solder strips.

[0117] According to the photovoltaic module provided in the embodiments of this application, by separating the pad 230 from the second grid line 220, that is, the pad 230 still provides connection points for the solder ribbon, but is not electrically connected to the second grid line 220, the current transmission in the second grid line 220 can be prevented from being affected by the resistivity change of the pad 230. In actual use, the performance and stability of the photovoltaic module can be improved.

[0118] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0119] In the description of this application, it should be understood that the terms "center", "width", "upper", "lower", "left", "right", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not 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 application.

[0120] In the description of this application, "first feature" and "second feature" may include one or more of the features.

[0121] In the description of this application, "multiple" means two or more.

[0122] In the description of this application, the first feature being "above" or "below" the second feature may include the first and second features being in direct contact, or the first and second features being in contact through another feature between them.

[0123] In the description of this application, the terms "above," "over," and "on top" for the first feature and the second feature include the first feature being directly above or diagonally above the second feature, or simply indicate that the first feature is at a higher horizontal level than the second feature.

[0124] 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., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0125] Although embodiments of this application 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 this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A type of battery cell, characterized in that, include: The battery cell itself; An electrode structure is disposed on the surface of the battery cell body. The electrode structure includes a first grid line and a second grid line. The first grid line extends along a first direction. Multiple first grid lines are spaced apart along a second direction perpendicular to the first direction. The second grid line extends along the second direction. Multiple second grid lines are spaced apart along the first direction. The first grid line and the second grid line with the same conductive polarity are connected. The first direction and the second direction are parallel to the plane in which the battery cell body is located. A solder pad is provided on the surface of the battery cell body. The solder pad is used to connect with a solder strip, which is used to conduct the current collected by the electrode structure. Wherein, the line width of the first gate line is smaller than the line width of the second gate line, and at least one of the pads is spaced apart from any of the second gate lines.

2. The battery cell according to claim 1, characterized in that, Any of the pads is spaced apart from any of the second gate lines.

3. The battery cell according to claim 1, characterized in that, Each of the pads is also spaced apart from any of the first gate lines.

4. The battery cell according to claim 1, characterized in that, The battery cell body has two first sides that are arranged opposite to each other along the second direction; The distance between the pad adjacent to the first side and the first side is 5mm-10mm.

5. The battery cell according to claim 1, characterized in that, The battery cell body has two first sides arranged opposite each other along the second direction. The battery cell body is provided with an edge region where the first sides are located and a central region located between the edge regions along the second direction. The second grid line is located at least in the edge region where the first sides are located.

6. The battery cell according to claim 5, characterized in that, The distance between the pad adjacent to the first side and the second gate line located in the edge region where the first side is located is 0.1mm-0.9mm.

7. The battery cell according to claim 5, characterized in that, The pads adjacent to the first side are disposed between the first critical gate line and the second critical gate line, wherein the first critical gate line and the second critical gate line are first gate lines with the same conduction polarity. Wherein, the first critical gate line is the first gate line that intersects with the second gate line located in the edge region and is the shortest distance from the center region along the second direction; the second critical gate line is located at the position of the first critical gate line along the second direction toward the center region, and the second critical gate line and the first critical gate line are separated by N first gate lines with the same conductivity, 0≤N≤5.

8. The battery cell according to claim 7, characterized in that, N＝0。 9. The battery cell according to claim 5, characterized in that, The second grid line is arranged in the edge region and the center region, or the second grid line is arranged only in the edge region.

10. The battery cell according to claim 5, characterized in that, The density of welding points in the central region of the solder strip is greater than the density of welding points in the edge region, and the welding points are used to connect the solder strip and the battery cell.

11. The battery cell according to claim 1, characterized in that, The first gate line has a thickened section, and no pads are provided between at least one pair of adjacent thickened sections along the second direction.

12. A photovoltaic module, characterized in that, include: At least one battery cell as described in any one of claims 1-11.

Images