Battery assembly and photovoltaic system

Abstract

The utility model provides a battery assembly and a photovoltaic system. The battery assembly comprises a first battery piece, a second battery piece and a third battery piece. The two ends of the second battery piece in the first direction are overlapped with the two opposite sides of the first battery piece and the third battery piece respectively. The battery assembly further comprises a first welding strip, and the first welding strip comprises a first connecting part, a conductive part and a second connecting part. The first connecting part comprises a first connecting point, and the first connecting point is the last connecting point of the first connecting part and the first battery piece in the first direction; the second connecting part comprises a second connecting point, and the second connecting point is a first connecting point of the second connecting part and the second battery piece in the first direction; the connecting line of the second connecting point and the first connecting point is a connecting line, a first included angle is formed between the connecting line and the first direction, and the first included angle ranges from 87 degrees to 90 degrees. According to the utility model, the two ends of the second battery piece are respectively overlapped with the two opposite sides of the first battery piece and the third battery piece, so that the abrasion of the edges of the battery pieces to the welding strip is reduced.

Description

Technical Field

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

[0002] In battery modules, adjacent cells are stacked and connected by solder ribbons to eliminate partial overlap between cells. However, this stacking method in related technologies causes the cells to tilt. The edges of the tilted cells exert additional mechanical pressure on the solder ribbons, leading to wear and a shorter lifespan. Therefore, reducing solder ribbon wear and improving its lifespan has become an urgent problem to be solved. Utility Model Content

[0003] This invention provides a battery module and a photovoltaic system to solve the technical problem of how to design battery modules to reduce solder ribbon wear and improve solder ribbon lifespan.

[0004] This utility model provides a battery module and a photovoltaic system. The battery module includes a first battery cell, a second battery cell, and a third battery cell arranged sequentially along a first direction. The two ends of the second battery cell in the first direction overlap with the opposite sides of the first and third battery cells, respectively. The battery module also includes a first solder strip, which includes a first connecting portion, a conductive portion, and a second connecting portion. The first connecting portion connects to the first battery cell. The conductive portion is bent from the first connecting portion and located between the first connecting portion and the second connecting portion. The second connecting portion is bent from the conductive portion and connects to the second battery cell. The first connecting portion includes a first connecting point, which is the last connecting point of the first connecting portion to the first battery cell in the first direction. The second connecting portion includes a second connecting point, which is the first connecting point of the second connecting portion to the first connecting point of the second battery cell in the first direction. The line connecting the second connecting point and the first connecting point is a connecting line, which forms a first angle with the first direction, the first angle being 87° to 90°.

[0005] In this invention, the battery assembly utilizes a second battery cell whose two ends in the first direction overlap with the opposite sides of the first and third battery cells. This reduces the tilt of the second battery cell, thereby reducing wear on the solder ribbon from the edges of the battery cell. Simultaneously, by setting the angle between the connecting line in the first solder ribbon and the first direction to 87° to 90°, the bending shape of the first solder ribbon more closely matches the overlapping shape of the three battery cells, reducing lamination damage to the first solder ribbon. This improves the service life of the first solder ribbon.

[0006] Furthermore, the width of the overlapping area between the first battery cell and the second battery cell is 0.1 mm to 3 mm.

[0007] Furthermore, along the first direction, the width of the overlapping area between the second and third battery cells is 0.1 mm to 3 mm.

[0008] This invention reduces the pressure exerted by the second battery cell on the first and third battery cells by reasonably setting the width range of the overlapping area between the first and second battery cells, and the width range of the overlapping area between the second and third battery cells, thus avoiding excessive pressure that could cause damage to the battery cells or the solder strips.

[0009] Furthermore, the ratio of the area of ​​the overlapping region of the first battery cell and the second battery cell to the area of ​​the overlapping region of the second battery cell and the third battery cell is 0.95 to 1.05.

[0010] In this way, the overlapping areas of the first and third solar cells with the second solar cell can be made to be roughly equal, so as to evenly distribute the weight of the second solar cell, avoid local stress concentration problems, and improve the stability of the solar cell assembly.

[0011] Furthermore, the first battery cell includes a first connecting structure, which is connected to the first connecting portion; the second battery cell includes a second connecting structure, which is connected to the second connecting portion; the area of ​​the first connecting structure is larger than the area of ​​the second connecting structure.

[0012] Thus, by increasing the contact area between the first connecting structure and the first connecting part, the welding pull force on the first connecting part is increased, and the incomplete welding of the solder strip is reduced.

[0013] Furthermore, the ratio between the length of the first connecting portion and the total length of the first solder strip is 0.03 to 0.5.

[0014] Furthermore, the ratio between the length of the second connecting portion and the length of the first welding strip is 0.03 to 0.5.

[0015] Furthermore, the ratio between the length of the conductive portion and the length of the first solder strip is 0.002 to 0.1.

[0016] Furthermore, the projection length of the connecting line on the first battery cell is 0mm to 10mm.

[0017] Furthermore, the first connecting portion of the first solder strip is connected to the first polar region of the first battery cell and connected to the second polar region of the second battery cell through the conductive portion and the second connecting portion.

[0018] This invention connects two adjacent battery cells by connecting the first solder strip to the first polarity region and the second polarity region of the two battery cells respectively.

[0019] This utility model embodiment also provides a photovoltaic system, which includes the battery module as described above. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of a photovoltaic system module provided in one embodiment of the present invention;

[0022] Figure 2 This is a partial cross-sectional structural diagram of a battery assembly provided in one embodiment of the present invention;

[0023] Figure 3 yes Figure 2 A partial enlarged view of the bonding diagram at point A in the battery assembly;

[0024] Figure 4 This is a schematic cross-sectional view of another part of the battery assembly provided in one embodiment of the present invention;

[0025] Figure 5 This is a partial cross-sectional schematic diagram of a battery assembly provided in one embodiment of the present invention;

[0026] Figure 6 This is a top view of a battery assembly provided in one embodiment of the present invention.

[0027] Key component symbols: 1000, photovoltaic system; 100, battery module; 10, first battery cell; 20, second battery cell; 30, third battery cell; 40, first solder strip; 50, second solder strip; 11, first connection structure; 21, second connection structure; 41, first connection part; 42, conductive part; 43, second connection part; 411, first connection point; 431, second connection point; L, connecting line; C, first included angle. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present utility model, and should not be construed as limiting the present utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0029] In the description of this utility model, it should be understood that the terms "length", "width", "upper", "lower", "top", "bottom", "lateral", "longitudinal", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0030] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this utility model, "a plurality of" means two or more, unless otherwise explicitly specified.

[0031] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows for communication; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model according to the specific circumstances.

[0032] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "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. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0033] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0034] Please see Figure 1 The photovoltaic system 1000 in this embodiment of the present invention may include the battery module 100. The battery module 100 may include a plurality of battery cells, which can be connected in series with solder strips to form a battery string. The battery strings in the battery module 100 can be connected in series, in parallel, or in a series-parallel combination to achieve current collection and output. For example, the connection between the battery strings can be achieved through busbars.

[0035] The accompanying drawings provided in this application are schematic diagrams, and some elements are not shown in the drawings. The purpose is to clearly describe the technical solution and highlight the key features of the utility model. It is not intended to limit the technical solution to exclude these unshown elements. That is to say, the drawings are merely examples and do not represent a limitation on the specific form of the battery module 100.

[0036] like Figures 2 to 6 As shown, in this embodiment of the present invention, the battery assembly 100 includes: a first battery cell 10, a second battery cell 20, and a third battery cell 30 arranged sequentially along a first direction. The second battery cell 20 overlaps with the opposite sides of the first battery cell 10 and the third battery cell 30 at both ends in the first direction. The battery assembly 100 also includes a first solder strip 40, which includes a first connecting portion 41, a conductive portion 42, and a second connecting portion 43. The first connecting portion 41 connects to the first battery cell 10. The conductive portion 42 is bent from the first connecting portion 41 and located between the first connecting portion 41 and the second connecting portion 43. The second connecting portion 43 is bent from the conductive portion 42 and connects to the second battery cell 20. The first connecting portion 41 includes a first connecting point 411, which is the last connecting point of the first connecting portion 41 to the first battery cell 10 in the first direction. The second connecting portion 43 includes a second connecting point 431, which is the first connecting point of the second connecting portion 43 to the first connecting point of the second battery cell 20 in the first direction. The line connecting the second connecting point 431 and the first connecting point 411 is a connecting line L, which forms a first angle C with the first direction. The first angle C is 87° to 90°.

[0037] Thus, in this embodiment of the present invention, the battery assembly 100, by having the two ends of the second battery sheet 20 overlap with the opposite sides of the first battery sheet 10 and the third battery sheet 30 in the first direction, reduces the tilt of the second battery sheet 20, thereby reducing the wear of the battery sheet edges on the first solder ribbon 40. Simultaneously, by setting the angle between the connecting line L in the first solder ribbon 40 and the first direction to 87° to 90°, the bending shape of the first solder ribbon 40 more closely conforms to the overlapping shape of the three battery sheets, which can reduce damage to the first solder ribbon 40 from the battery sheets during lamination. This improves the service life of the solder ribbon.

[0038] Meanwhile, the bending shape of the first solder ribbon 40 better matches the overlapping shape of the three battery cells, which can reduce the wear of the solder ribbon on the battery cells, thereby improving the service life of the battery cells and thus improving the stability and service life of the battery module 100. It is worth noting that in this embodiment, the "first direction" refers to the arrangement direction of each battery cell. Specifically, the first battery cell 10 and the third battery cell 30 are spaced apart along the first direction, and the second battery cell 20 is stacked on top of the first battery cell 10 and the third battery cell 30. The first battery cell 10 and the third battery cell 30 respectively support one end of the second battery cell 20, so that the first battery cell 10, the second battery cell 20 and the third battery cell 30 are arranged in a "triangular" structure. In this way, each battery cell in the battery module 100 can remain horizontal during lamination, reducing the wear of the battery cell edges on the first solder ribbon 40.

[0039] Simultaneously, this arrangement ensures that the first solar cell 10, the second solar cell 20, and the third solar cell 30 are arranged in a "triangular" pattern. It also allows each solar cell in the battery module 100 to remain horizontal rather than tilted in its natural state. This further reduces the risk of microcracks in the overlapping areas of the solar cells during lamination.

[0040] It is worth noting that the battery module 100 may have one or more triangular structures. In a battery module 100 that includes multiple triangular structures, a battery cell may specifically be a first battery cell 10 in one triangular structure, and may also be a third battery cell 30 or a second battery cell 20 in other triangular structures.

[0041] In actual layout, when the battery module 100 includes multiple battery cells, the multiple battery cells can be arranged in a triangular or ternary configuration. When the multiple battery cells are arranged in a triangular configuration, the triangular configuration can be combined with other arrangements to connect the multiple battery cells. For example, the first third of the battery cells can be arranged in a triangular configuration, the middle battery cells can be arranged in a flat configuration (i.e., multiple battery cells are placed horizontally without overlapping areas and connected sequentially using solder ribbons), and the last battery cells can be arranged in a shingled configuration (i.e., multiple battery cells are stacked; the specific arrangement method can refer to existing common arrangement methods, which will not be elaborated here).

[0042] In some embodiments, various combinations of solar cells can be used for arrangement, and this invention does not limit this. Combining multiple solar cells using various arrangement methods can optimize the cell layout and improve module packaging efficiency. More solar cells can be placed within the same module area compared to conventional arrangements. It also offers advantages such as higher output power, lower internal losses, and less hot spot effect.

[0043] In some embodiments, the first solar cell 10, the second solar cell 20, and the third solar cell 30 in this invention can be complete solar cells, or they can be half solar cells or multiple solar cells, etc., without limitation. A half solar cell or multiple solar cells are made by cutting a single solar cell along one of its lines. The number of half solar cells, three-section solar cells, or multiple solar cells can be multiple and arranged in an array.

[0044] Furthermore, such as Figures 2 to 6 As shown, the first solder strip 40 connects the first battery cell 10 and the second battery cell 20 respectively, making the first battery cell 10 and the second battery cell 20 electrically connected. The first connecting part 41 is specifically located on the side of the first battery cell 10 facing the second battery cell 20, and the second connecting part 43 is specifically located on the side of the second battery cell 20 away from the first battery cell 10. The conductive part 42 is connected to the first connecting part 41 and the second connecting part 43 respectively.

[0045] It is worth noting that the first connecting part 41 has multiple connection points with the first battery cell 10 in the first direction, and the first connection point 411 is the last connection point. The second connecting part 43 has multiple connection points with the second battery cell 20 in the first direction, and the second connection point 431 is the first connection point.

[0046] Furthermore, in order to conform to the overlapping shape of the three battery cells, the bending shape of the solder ribbon needs to be adjusted accordingly to reduce wear on the solder ribbon during the lamination of the battery module 100. Therefore, by adjusting the first included angle C, the bending shape of the first solder ribbon 40 can be adjusted accordingly.

[0047] Specifically, setting the first included angle C to 87° to 90° allows the bending shape of the solder ribbon to better conform to the overlapping shape of the three battery cells, thereby reducing the damage to the solder ribbon caused by lamination. For example, the first included angle C can be 87°, 87.5°, 88°, 88.5°, 89.5°, or 90°.

[0048] Preferably, such as Figure 4 As shown, the first included angle C can be set to 90°. This makes the bending shape of the first solder strip 40 best fit the overlapping shape of the three battery cells.

[0049] Furthermore, the projected length of the connecting line L on the first solar cell 10 is 0mm to 10mm. For example, it is 0mm, 0.5mm, 1mm, 2mm, 3mm, 5mm, 8mm, or 10mm. This allows the bending shape of the first solder ribbon 40 to better conform to the overlapping shape of the three solar cells, reducing the damage to the first solder ribbon 40 caused by lamination.

[0050] Furthermore, such as Figure 5 and Figure 6 The battery assembly 100 also includes a second solder strip 50, which connects the second battery cell 20 and the third battery cell 30 respectively, making the second battery cell 20 and the third battery cell 30 electrically connected. The specific structure and arrangement of the second solder strip 50 can be referred to the first solder strip 40, and will not be described again here.

[0051] When the first solar cell 10, the second solar cell 20, and the third solar cell 30 are configured as back-contact batteries, the back surface of the three solar cells is provided with multiple alternately arranged first polarity regions (not shown in the figure) and second polarity regions (not shown in the figure). Each polarity region is provided with a solder strip for connecting two adjacent solar cells. The polarities of the first polarity region and the second polarity region are opposite.

[0052] In some embodiments, each solar cell may have multiple solder ribbons for connecting two adjacent solar cells. When connecting multiple polarity regions of two adjacent solar cells, multiple solder ribbons can be used for connection. For example, a first solder ribbon 40 can be used to connect to the first polarity region of the first solar cell 10 and then sequentially to the second polarity region of the second solar cell 20; then a second solder ribbon 50 can be used to connect to the first polarity region of the second solar cell 20 and then sequentially to the second polarity region of the third solar cell 30. The first polarity region and the second polarity region can be either a positive polarity region or a negative polarity region; for example, the first polarity region can be a positive polarity region (P-region), and the second polarity region can be a negative polarity region (N-region).

[0053] This invention connects two adjacent battery cells by connecting the first solder strip 40 to the first polarity region and the second polarity region of the battery cell respectively.

[0054] The solder strips in this invention can be made of tin-plated copper, aluminum, or silver. The solder strips generally use high-purity copper as the base material, with a tin layer coated on its surface. This prevents the copper base material from oxidizing and discoloring, and also facilitates the soldering of the material to the grid lines of the battery cells. The battery module 100 typically includes multiple types of solder strips. For example, solder strips used for single-cell soldering and series soldering of battery cells are called interconnect solder strips, and solder strips used for parallel battery strings are called busbars. The number of interconnect solder strips and busbars in the battery module 100 can be reasonably set according to actual needs. In some embodiments, the first solder strip 40 and the second solder strip 50 in this invention are interconnect solder strips, and multiple busbars can also be provided for parallel battery strings.

[0055] Specifically, in this embodiment of the invention, the types of the first solder strip 40 and the second solder strip 50 are not limited to meet different needs. For example, the first solder strip 40 and the second solder strip 50 can be round solder strips or flat wide solder strips.

[0056] In some embodiments, the cross-sectional shape of the first solder strip 40 and the second solder strip 50 is circular, rectangular, or triangular, etc. In practical applications, the cross-sectional shape of the solder strips can be flexibly selected according to process requirements and the performance requirements of the solar cells.

[0057] like Figure 5As shown, in one possible implementation, the width D1 of the overlapping area between the first battery cell 10 and the second battery cell 20 along the first direction is 0.1 mm to 3 mm. For example, it is 0.1 mm, 1 mm, 1.5 mm, 2 mm, or 3 mm. This allows the first battery cell 10 to support the second battery cell 20 while minimizing shading of the first battery cell 10. Because if the width D1 of the overlapping area between the first battery cell 10 and the second battery cell 20 is too small, the first battery cell 10 will not have enough area to support the second battery cell 20; if the width D1 of the overlapping area is too large, the second battery cell 20 will significantly shade the first battery cell 10, affecting the power generation efficiency of the first battery cell 10.

[0058] In one possible implementation, along the first direction, the width D2 of the overlapping area between the second solar cell 20 and the third solar cell 30 is 0.1 mm to 3 mm. For example, it is 0.1 mm, 1 mm, 1.5 mm, 2 mm, or 3 mm. This allows the third solar cell 30 to support the second solar cell 20 while minimizing shading of the second solar cell 20. If the width D2 of the overlapping area is too small, the third solar cell 30 will not have enough space to support the second solar cell 20; if the width D2 is too large, the second solar cell 20 will significantly shade the third solar cell 30, affecting its power generation efficiency.

[0059] This invention reduces the pressure exerted by the second battery cell 20 on the first battery cell 10 and the third battery cell 30 by reasonably setting the width range of the overlapping area of ​​the first battery cell 10 and the second battery cell 20, and the width range of the overlapping area of ​​the second battery cell 20 and the third battery cell 30, thereby avoiding excessive pressure that could cause damage to the battery cells or the solder strips.

[0060] like Figure 5 As shown, in one possible implementation, the ratio of the area of ​​the overlap region between the first battery cell 10 and the second battery cell 20 and the area of ​​the overlap region between the second battery cell 20 and the third battery cell 30 is 0.95 to 1.05. This makes the areas of the overlap regions of the first battery cell 10 and the third battery cell 30 with the second battery cell 20 roughly equivalent, thus uniformly distributing the weight of the second battery cell 20, avoiding localized stress concentration problems, and improving the stability of the battery assembly 100.

[0061] Preferably, the ratio of the area of ​​the overlapping region of the first battery cell 10 and the second battery cell 20 to the area of ​​the overlapping region of the second battery cell 20 and the third battery cell 30 can be 1. In this way, the overlapping regions of the first battery cell 10 and the second battery cell 20 and the second battery cell 20 and the third battery cell 30 have the same area, and the first battery cell 10 and the third battery cell 30 have the best stress-dispersing effect on the second battery cell 20.

[0062] like Figure 5 and Figure 6 As shown, in one possible implementation, the first battery cell 10 includes a first connecting structure 11 connected to a first connecting portion 41; the second battery cell 20 includes a second connecting structure 21 connected to a second connecting portion 43, and the area of ​​the first connecting structure 11 is larger than the area of ​​the second connecting structure 21. Because the two ends of the second battery cell 20 in the first direction overlap with the opposite sides of the first battery cell 10 and the third battery cell 30, a height difference is formed between the second battery cell 20 and the first battery cell 10, causing the position of the first connecting portion 41 to be slightly "suspended," resulting in relatively less pressure on it during lamination compared to the second connecting portion 43. Therefore, the first connecting portion 41 is prone to poor soldering.

[0063] Therefore, the area of ​​the first connecting structure 11 is set to be larger than the area of ​​the second connecting structure 21, so as to increase the contact area between the first connecting structure 11 and the first connecting part 41, increase the welding pull force on the first connecting part 41, and reduce the incomplete welding of the welding strip.

[0064] It is worth noting that the types of the first connection structure 11 and the second connection structure 21 are not limited in this application embodiment, in order to meet different needs. In one embodiment, when the first connection structure 11 and / or the second connection structure 21 is solder paste, the solder paste has good wetting and flowability, suitable for filling irregular spaces, and ensuring the stability of the electrical connection. In another embodiment, when the first connection structure 11 and / or the second connection structure 21 is conductive adhesive, the conductive adhesive has softness and good adhesion, and can tightly adhere to the space between the cell grid lines and the solder ribbon. In yet another embodiment, when the first connection structure 11 and / or the second connection structure 21 is other metallic conductive materials, the metallic materials have excellent conductivity, which can ensure efficient current conduction and further improve the power generation efficiency of the battery module 100.

[0065] Furthermore, when the first connection structure 11 and / or the second connection structure 21 are solder paste and conductive adhesive, the application process can be completed through a simple coating or dispensing process, which is convenient and cost-effective.

[0066] like Figures 2 to 6As shown, further, the ratio between the length of the first connecting portion 41 and the total length of the first solder strip 40 is 0.03 to 0.5. For example, the ratio between the length of the first connecting portion 41 and the total length of the first solder strip 40 can be 0.03, 0.05, 0.08, 0.1, 0.2, 0.3, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, or 0.5.

[0067] Thus, the ratio between the length of the first connecting part 41 and the total length of the first solder strip 40 is within this range, which on the one hand allows sufficient bending length for the conductive part 42, and on the other hand allows the first connecting part 41 to have sufficient length to connect the grid lines in the first battery cell 10.

[0068] Specifically, the length of the first connecting portion 41 in the first direction can be set to 90mm to 93mm. For example, it can be 91mm, 92mm, or 93mm.

[0069] Furthermore, the ratio between the length of the second connecting portion 43 and the total length of the first solder strip 40 is 0.03 to 0.5. For example, the ratio between the length of the first connecting portion 41 and the total length of the first solder strip 40 can be 0.03, 0.05, 0.08, 0.1, 0.2, 0.3, 0.4, 0.41, 0.42, 0.43, 0.44, 0.45, or 0.5.

[0070] Thus, the ratio between the length of the second connecting part 43 and the total length of the first solder strip 40 is within this range, which on the one hand allows sufficient bending length for the conductive part 42, and on the other hand allows the second connecting part 43 to have sufficient length to connect the grid lines in the second battery cell 20.

[0071] Specifically, the length of the second connecting portion 43 in the first direction can be set to 90mm to 93mm. For example, it can be 91mm, 92mm, or 93mm.

[0072] Furthermore, the ratio between the length of the second connecting portion 43 and the length of the first connecting portion 41 is 0.95 to 1.05. For example, it is 0.95, 0.96, 0.98, 1, 1.02, or 1.05. This ensures that the placement length of the first solder ribbon 40 is substantially the same for the first battery cell 10 and the second battery cell 20, simplifying the arrangement of the solder ribbon.

[0073] Preferably, the ratio between the length of the second connecting portion 43 and the length of the first connecting portion 41 is 1, such that the first solder strip 40 has the same placement length in the first battery cell 10 and the second battery cell 20.

[0074] Furthermore, the ratio between the length of the conductive portion 42 and the length of the first solder strip 40 is 0.002 to 0.1. For example, it is 0.002, 0.0025, 0.003, 0.0035, 0.004, 0.006, 0.008, 0.01, 0.015, 0.02, 0.04, 0.06, 0.08, 0.09, 0.091, 0.092, 0.094, 0.095, 0.098, or 0.1. Thus, on the one hand, the conductive portion 42 has sufficient bending length for bending, and on the other hand, it also provides sufficient space for the first connecting portion 41 and the second connecting portion 43 to connect the grid lines in the battery cell.

[0075] It is understood that in such embodiments, the battery module 100 may further include a frame, a backsheet, photovoltaic glass, and an encapsulating film. The encapsulating film may be filled between the front and back of the battery cells, as well as between the photovoltaic glass and adjacent battery cells. As a filler, it may be a transparent colloid with good light transmittance and aging resistance. For example, the encapsulating film may be an EVA film or a POE film, and the specific choice can be made according to the actual situation, without limitation.

[0076] Photovoltaic glass can be applied to the encapsulating film on the front of the solar cell. This photovoltaic glass can be ultra-clear glass, possessing high light transmittance, high transparency, and superior physical, mechanical, and optical properties. For example, ultra-clear glass can achieve a light transmittance of over 92%, protecting the solar cell while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the solar cell together, providing sealing, insulation, and waterproofing / moisture protection for the cell.

[0077] The backsheet can be attached to the adhesive film on the back of the solar cells. The backsheet protects and supports the cells, providing reliable insulation, water resistance, and aging resistance. Multiple backsheet options are available, typically including tempered glass, acrylic glass, and aluminum alloy TPT composite adhesive film, etc. The specific choice depends on the specific circumstances and is not limited here. The backsheet, solar cells, adhesive film, and photovoltaic glass can be integrated into a frame. The frame serves as the main external support structure for the entire solar module 100, providing stable support and installation. For example, the solar module 100 can be installed at the desired location via the frame.

[0078] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an 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.

[0079] Furthermore, the above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A battery assembly, characterized in that, It includes a first battery cell, a second battery cell, and a third battery cell arranged sequentially along a first direction, wherein the two ends of the second battery cell in the first direction overlap with the opposite sides of the first battery cell and the third battery cell, respectively. The battery assembly further includes a first solder strip, which includes a first connecting portion, a conductive portion, and a second connecting portion. The first connecting portion connects to the first battery cell, the conductive portion is bent from the first connecting portion and located between the first connecting portion and the second connecting portion, and the second connecting portion is bent from the conductive portion and connects to the second battery cell. The first connecting portion includes a first connecting point, which is the last connecting point of the first connecting portion to the first battery cell in the first direction; The second connecting portion includes a second connecting point, which is the first and second connecting point of the second connecting portion and the first and second battery cells in the first direction; The line connecting the second connection point and the first connection point is a connecting line, and the connecting line forms a first angle with the first direction, the first angle being 87° to 90°.

2. The battery assembly according to claim 1, characterized in that, Along the first direction, the width of the overlapping area between the first battery cell and the second battery cell is 0.1 mm to 3 mm.

3. The battery assembly according to claim 1 or 2, characterized in that, Along the first direction, the width of the overlapping area between the second and third battery cells is 0.1 mm to 3 mm.

4. The battery assembly according to claim 1, characterized in that, The ratio of the area of ​​the overlapping region of the first battery cell and the second battery cell to the area of ​​the overlapping region of the second battery cell and the third battery cell is 0.95 to 1.

05.

5. The battery assembly according to claim 1, characterized in that, The first battery cell includes a first connection structure, which is connected to the first connection portion; The second battery cell includes a second connection structure, which is connected to the second connection portion; The area of ​​the first connecting structure is larger than the area of ​​the second connecting structure.

6. The battery assembly according to claim 1, characterized in that, The ratio between the length of the first connecting portion and the total length of the first solder strip is 0.03 to 0.

5.

7. The battery assembly according to claim 1, characterized in that, The ratio between the length of the second connecting portion and the length of the first welding strip is 0.03 to 0.

5.

8. The battery assembly according to claim 1, characterized in that, The ratio between the length of the conductive portion and the length of the first solder strip is 0.002 to 0.

1.

9. The battery assembly according to claim 1, characterized in that, The projected length of the connecting line on the first battery cell is 0mm to 10mm.

10. The battery assembly according to claim 1, characterized in that, The first connecting portion of the first solder strip is connected to the first polar region of the first battery cell and connected to the second polar region of the second battery cell through the conductive portion and the second connecting portion.

11. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1 to 10.

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