Battery assembly and photovoltaic system

Abstract

The utility model provides a battery assembly and a photovoltaic system. The battery assembly comprises a battery module and a plurality of junction boxes electrically connected with the battery module, the battery module comprises a plurality of battery strings arranged in the first direction, each battery string comprises a plurality of battery pieces arranged in the second direction, and the first direction intersects with the second direction; a distance is formed between the center line of the battery assembly and the junction box in the second direction, and the center line extends in the first direction. According to the battery assembly, the distance is set between the center line of the battery assembly and the junction box in the second direction. Therefore, the junction box can be shifted from the middle part with larger stress in the battery assembly, so that the stress borne by the battery piece at the middle part of the battery assembly can be reduced, the risks of subfissure and fragment of the battery piece can be further reduced, and the service life of the battery assembly is prolonged.

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] When a battery module is subjected to external mechanical forces, the central portion experiences greater stress compared to other areas. In related technologies, a junction box is typically placed in the middle of the battery module. However, the presence of the junction box reduces the bending stress that the central region can withstand, thereby increasing the risk of microcracks and fragmentation of the battery cells. Therefore, reducing the risk of microcracks and fragmentation of battery cells in battery modules 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 reduce the risk of microcracks and fragments in battery cells within the battery module.

[0004] This utility model embodiment is implemented as follows: the battery assembly includes a battery module and a junction box electrically connected to the battery module; the battery assembly includes a battery module and a plurality of junction boxes electrically connected to the battery module; the battery module includes a plurality of battery strings arranged along a first direction; each battery string includes a plurality of battery cells arranged along a second direction; the first direction and the second direction intersect; the centerline of the battery assembly and the junction box are spaced apart in the second direction; the centerline extends along the first direction.

[0005] Furthermore, the distance between the junction box and the center line in the second direction is 30mm to 100mm.

[0006] Furthermore, the distance between the junction box and the center line in the second direction is D1, and the size of the battery cell in the second direction is D2; 0.2·D2<D1<3·D2.

[0007] Furthermore, each of the junction boxes is arranged collinearly in the second direction.

[0008] Furthermore, at least two of the plurality of junction boxes have a first spacing in the second direction, the first spacing being 10m to 500mm.

[0009] Furthermore, at least two of the plurality of junction boxes have a second spacing in the second direction, the second spacing being 60mm to 100mm.

[0010] Furthermore, all of the junction boxes in the plurality of junction boxes are staggered from each other in the second direction, and any two junction boxes have a third distance in the second direction, the third distance being 10m to 500mm.

[0011] Furthermore, all of the junction boxes in the plurality of junction boxes are staggered from each other in the second direction, and any two junction boxes have a fourth spacing in the second direction, the fourth spacing being 60mm to 100mm.

[0012] Furthermore, the plurality of junction boxes includes a first junction box and a second junction box; the first junction box and the second junction box are respectively disposed on both sides of the center line in the second direction, and the distance between the first junction box and the second junction box in the second direction is less than or equal to 200mm.

[0013] Furthermore, the battery assembly includes a first edge and a second edge arranged along the second direction, both the first edge and the second edge extending along the first direction, the distance between the junction box and the first edge is a fifth distance, the distance between the junction box and the second edge is a sixth distance, and the fifth distance is not equal to the sixth distance.

[0014] Furthermore, the fifth spacing is 600mm to 1500mm.

[0015] This utility model embodiment also provides a photovoltaic system, which includes the battery module as described above.

[0016] The battery module in this application has a certain distance between its centerline and the junction box in a second direction. This allows the junction box to be offset from the more stressful central part of the battery module, thereby reducing the stress on the battery cells in the central part of the battery module. This reduces the risk of microcracks and fragmentation of the battery cells and extends the life of the battery module. Attached Figure Description

[0017] 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.

[0018] Figure 1 This is a schematic diagram of a photovoltaic system module provided in one embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the structure of a battery assembly provided in one embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of this utility model;

[0021] Figure 4 This is a schematic diagram of the structure of the battery string in a battery assembly provided in one embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0025] Figure 8 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0026] Figure 9 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of this utility model;

[0027] Figure 10 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0028] Figure 11 This is a schematic diagram of the structure of a battery assembly provided in another embodiment of the present invention;

[0029] Figure 12 This is a partial structural schematic diagram of a battery assembly provided in one embodiment of the present invention;

[0030] Figure 13 This is a partial structural schematic diagram of a battery assembly provided in another embodiment of the present invention;

[0031] Figure 14 This is a partial structural schematic diagram of a battery assembly provided in another embodiment of the present invention;

[0032] Figure 15 This is a partial structural schematic diagram of a battery assembly provided in one embodiment of the present invention;

[0033] Figure 16 This is a partial structural schematic diagram of a battery assembly provided in another embodiment of the present invention;

[0034] Figure 17 This is a partial structural schematic diagram of a battery assembly provided in another embodiment of the present invention;

[0035] Figure 18 This is a partial structural schematic diagram of a battery assembly provided in another embodiment of the present invention.

[0036] Key component symbols: 1000, Photovoltaic system; 100, Battery module; 101, Center line; 102, First edge; 103, Second edge; 10, Battery string; 11, Battery cell; 20, Junction box; 21, First junction box; 22, Second junction box; 23, Third junction box; 30, Frame structure; 40, Busbar; 201, Third edge; 204, Fourth edge; 211, Fifth edge; 212, Sixth edge; 221, Seventh edge; 222, Eighth edge. Detailed Implementation

[0037] 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.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] Please see Figure 1 The photovoltaic system 1000 in this embodiment of the present invention may include the battery module 100 in this embodiment of the present invention. The battery module 100 in this embodiment of the present invention may include several battery modules in this embodiment of the present invention. Multiple battery cells 11 can be connected in series to form a battery string 10. The battery strings 10 can be connected in series, in parallel, or in a series-parallel combination to form the battery module in this embodiment of the present invention, thereby realizing the current collection and output. For example, the connection between the battery strings 10 can be realized by a bus bar 40.

[0043] In this embodiment, the photovoltaic system 1000 can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants. It can also be applied to equipment or devices that generate electricity using solar energy, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it is understood that the application scenarios of the photovoltaic system 1000 are not limited to these; that is, the photovoltaic system 1000 can be applied in all fields that require solar energy for power generation. Taking a photovoltaic power generation system grid as an example, the photovoltaic system 1000 may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array may be an array combination of multiple battery modules 100. For example, multiple battery modules 100 can form multiple photovoltaic arrays. The photovoltaic array is connected to the combiner box, which can collect the current generated by the photovoltaic array. The collected current flows through the inverter and is converted into AC power required by the mains power grid before being connected to the mains power grid to achieve solar power supply.

[0044] The accompanying drawings provided in this utility model 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 points 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 back contact battery.

[0045] like Figures 2 to 11As shown, the battery assembly 100 in this embodiment of the present invention includes a battery module and a plurality of junction boxes 20 electrically connected to the battery module. The battery module includes a plurality of battery strings 10 arranged along a first direction, and each battery string 10 includes a plurality of battery cells 11 arranged along a second direction. The first direction and the second direction intersect. In this embodiment of the present invention, the first direction is a horizontal direction, which is also the length direction of the battery cells 11 and the width direction of the battery assembly 100. The second direction is a vertical direction, which is also the width direction of the battery cells 11 and the length direction of the battery assembly 100. The first direction and the second direction are perpendicular to each other.

[0046] The centerline 101 of the battery assembly 100 is spaced from the junction box 20 in a second direction, and the centerline 101 extends along a first direction. Each junction box 20 is provided with a diode, which is electrically connected to the battery module.

[0047] Therefore, in this application, the battery module 100 has a gap between its centerline 101 and the junction box 20 in a second direction. This allows the junction box 20 to be offset from the central region of the battery module 100 where stress is higher, thereby increasing the bending stress that the central region of the battery module 100 can withstand. This reduces the risk of microcracks and fragmentation of the battery cells 11 in the battery module 100, and extends the lifespan of the battery module 100.

[0048] Furthermore, the center line 101 is a geometric center line in the geometric layout of the battery assembly 100, and the extension direction of the center line 101 is the same as the arrangement direction of the battery strings 10 of the battery assembly 100, which can divide the battery assembly 100 into two parts of equal length along the second direction. For example, cutting the battery assembly 100 along the center line 101 can obtain two parts of equal length.

[0049] The center line 101 extends along the first direction. The center line 101 can be the geometric center line of the battery assembly 100 in the length direction or in the width direction, and is not limited here.

[0050] For example, for a battery assembly 100 with a dimension of 2465 mm in a first direction and a dimension of 1303 mm in a second direction, the center line 101 can divide the battery assembly 100 into two parts, each with a dimension of 1232.5 mm in the first direction and a dimension of 1303 mm in the second direction.

[0051] For example, for a battery assembly 100 with a dimension of 2465mm in both the first and second directions, the centerline 101 can divide the battery assembly 100 into two parts, each with a dimension of 1232.5mm in the first direction and 2465mm in the second direction.

[0052] For example, for a battery assembly 100 with a dimension of 1303 mm in a first direction and a dimension of 2465 mm in a second direction, the center line 101 can divide the battery assembly 100 into two parts, each with a dimension of 651.2 mm in the first direction and a dimension of 2465 mm in the second direction.

[0053] In the battery module 100, the centerline 101 and its vicinity experience greater stress compared to other locations within the battery module 100. Therefore, positioning the junction box 20 at a distance from the centerline 101 of the battery module 100 in the second direction avoids stress superposition between the junction box 20 and the centerline 101 and its vicinity, thereby increasing the bending stress that the central region of the battery module 100 can withstand. This reduces the risk of microcracks and fragmentation of the battery cells 11, extending the lifespan of the battery module 100. Experiments show that when the distance D1 between the junction box 20 and the centerline 101 of the battery module 100 in the second direction is 50 mm, the probability of microcracks in the battery cells 11 along the centerline 101 of the battery module 100 can be reduced by 3% to 8%.

[0054] Furthermore, in the battery assembly 100, the center line 101 and its surrounding area generate more heat compared to other locations within the battery assembly 100. In related technologies, the junction box 20 is positioned on the center line 101 of the battery assembly 100, which further increases the heat concentration in the middle portion of the battery assembly 100, leading to hot spots, reduced efficiency, and shortened lifespan.

[0055] Therefore, in this application, the battery module 100 is designed with a distance between the junction box 20 and the center line 101 of the battery module 100 in the second direction. The junction box 20 can also be offset from the central part of the battery module 100 where heat is concentrated, thereby reducing heat concentration in the central part of the battery module 100, thus reducing hot spots, increasing efficiency, and extending lifespan. Experiments show that when the distance D1 between the junction box 20 and the center line 101 of the battery module 100 in the second direction is 100mm, the peak temperature near the center line 101 of the battery module 100 can be reduced by 8°C to 12°C.

[0056] It is understandable that, such as Figure 3 , Figure 12 and Figure 13 As shown, the distance D1 between the junction box 20 and the center line 101 of the battery assembly 100 in the second direction refers to the minimum distance between the junction box 20 and the center line 101 of the battery assembly 100 in the second direction. In other words, the distance between the junction box 20 and the center line 101 of the battery assembly 100 in the second direction refers to the distance between the edge of the junction box 20 and the center line 101 of the battery assembly 100 in the second direction.

[0057] Furthermore, the distance D1 between the junction box 20 and the center line 101 of the battery assembly 100 in the second direction specifically refers to the distance between the edge of the junction box 20 on the side closer to the center line 101 of the battery assembly 100 and the center line 101 of the battery assembly 100 in the second direction.

[0058] Specifically, the junction box 20 includes a third edge 201 and a fourth edge 202 arranged along the second direction. The distance between the third edge 201 and the center line 101 in the second direction is less than the distance between the fourth edge 202 and the center line 101 in the second direction. That is, the third edge 201 is the edge of the junction box 20 that is closer to the center line 101 in the second direction. The distance between the junction box 20 and the center line 101 of the battery assembly 100 in the second direction refers to the distance between the third edge 201 and the center line 101 of the battery assembly 100 in the second direction.

[0059] like Figure 12 and Figure 13 As shown, the third edge 201 is specifically the edge of the junction box 20 facing the center line 101. The third edge 201 can be the upper edge or the lower edge of the junction box 20, which is not limited here.

[0060] Specifically, the solar cell 11 can be a back-contact solar cell 11. Further, the solar cell 11 can be formed by cutting a whole solar cell into two, three, four, five, or other equal parts. The solar cell 11 can be formed by cutting a whole solar cell into two equal parts. The specific division ratio of the whole solar cell is not limited here.

[0061] Furthermore, the cutting direction of the entire solar cell can be parallel to the extension direction of the fine grid of the solar cell, perpendicular to the extension direction of the fine grid, or at other angles to the extension direction of the fine grid.

[0062] Furthermore, all the solar cells 11 in the battery module are made of solar cells of the same area divided into equal proportions. Thus, all the solar cells 11 in the battery module have the same current, and the voltage is unaffected, resulting in the same power output. Therefore, no further processing for current or power matching is required.

[0063] Specifically, the solar cell 11 includes at least one of IBC cells, PERC cells, and Topcon cells. The specific form of the entire solar cell 11 is not limited here.

[0064] Specifically, the solar cell 11 can be a cell with a main grid or a cell without a main grid.

[0065] Furthermore, the entire solar cells 11 in the battery module can be of the same or different types; their areas can be the same or different.

[0066] Specifically, the battery module, after being packaged, can form a battery module 100. The battery module 100 can be a double-glass module or a single-glass module; the layout of the battery module 100 can be a 54-pane, 60-pane, 72-pane, or other layouts. No specific limitation is made to the specific form of the battery module 100 here.

[0067] Specifically, the battery assembly 100 also includes a frame structure 30 disposed around the battery module. The battery assembly 100 also has a busbar 40 connected to the battery in the junction box 20.

[0068] like Figure 2 As shown, in one possible implementation, the distance D1 between the junction box 20 and the center line 101 in the second direction is 30mm to 100mm. For example, it can be 30mm, 35mm, 40mm, 50mm, 55mm, 60mm, 70mm, 80mm, 90mm, or 100mm. It is understood that when the distance D1 between the junction box 20 and the center line 101 in the second direction is less than 30mm, the junction box 20 remains near the center line 101 of the battery assembly 100, and the junction box 20 does not deviate from the location of stress concentration and heat concentration in the battery assembly 100. However, when the distance D1 between the junction box 20 and the center line 101 in the second direction is greater than 100mm, it significantly increases the wiring complexity between the junction box 20 and the battery module, thereby increasing the cost of the battery assembly 100.

[0069] Therefore, the distance D1 between each junction box 20 and the center line 101 in the second direction is 30mm to 100mm. This can increase the bending stress that the middle area of ​​the battery module 100 can withstand while avoiding excessive cost of the battery module 100, and reduce stress concentration and heat concentration in the middle area of ​​the battery module 100, thereby improving the efficiency of the battery module 100 and extending its service life.

[0070] like Figure 2 and Figure 3As shown, in one possible implementation, the distance between the junction box 20 and the center line 101 in the second direction is D1, and the size of the battery cell 11 in the second direction is D2; 0.2·D2 < D1 < 3·D2. This ensures that each junction box 20 is completely isolated from the high-stress and high-heat areas near the center line 101 of the battery assembly 100, thereby improving the efficiency of the battery assembly 100 and extending its service life. Simultaneously, it avoids further increasing the wiring complexity between the junction box 20 and the battery module, thus reducing the cost of the battery assembly 100. Furthermore, in this embodiment, the offset distance between the junction box 20 and the center line 101 can be specifically matched to the size of the battery cell 11, thereby flexibly accommodating battery cells 11 of different sizes and improving the flexibility of the junction box 20's configuration.

[0071] Specifically, the configuration method for each junction box 20 is as follows: Figure 2 and Figure 3 As shown, each junction box 20 can be located on one side of the center line 101 in the second direction; or, it can be arranged as follows: Figure 7 As shown, each junction box 20 is located on the opposite side of the center line 101 in the second direction; or, it can be arranged as follows: Figure 4 and Figure 5 As shown, a portion of each junction box 20 is located on one side of the center line 101 in the second direction, and another portion of each junction box 20 is located on the other side of the center line 101 in the second direction. No limitation is made here.

[0072] like Figure 2 and Figure 7 As shown, in one possible implementation, the junction boxes 20 are arranged collinearly in the first direction. In other words, the junction boxes are not spaced apart in the second direction. This reduces the wiring complexity between the junction boxes 20 and the battery module, thereby reducing the cost of the battery assembly 100. Understandably, due to existing manufacturing processes, the junction boxes 20 may not be perfectly collinear in a geometric sense. For example, two adjacent junction boxes 20 may be misaligned by no more than 1 mm in the first direction, which can also be considered as collinear.

[0073] It is understandable that the fact that each junction box 20 is collinear in the first direction means that the geometric center of each junction box 20 is located on a straight line extending along the first direction.

[0074] like Figure 5 , Figure 8 , Figure 9 , Figure 10 , Figure 11As shown, in one possible implementation, at least two of the multiple junction boxes 20 are staggered relative to each other in a second direction. Since the staggered junction boxes 20 can disperse the stress borne by the battery assembly 100, they can increase the bending stress that the middle region of the battery assembly 100 can withstand, thereby effectively reducing stress concentration in the battery assembly 100, thus reducing the risk of microcracks in the battery cells 11 and improving the stability of the battery assembly 100. Simultaneously, the heat generated by each junction box 20 can also be dispersed, thereby reducing heat concentration in the battery module, reducing hot spots in the battery assembly 100, increasing the efficiency of the battery assembly 100, and extending the lifespan of the battery assembly 100.

[0075] It is understandable that at least two of the multiple junction boxes 20 are offset from each other in the second direction. This means that the junction boxes 20 are not perfectly aligned in the second direction; at least two junction boxes 20 are not flush with each other. In other words, if a junction box 20 is placed at a certain location on the battery module, then when another junction box 20 is placed, it will be displaced (offset or misaligned) relative to the previous junction box 20 in the second direction, rather than being located at the same position in the second direction.

[0076] It is understandable that placing the junction box 20 in the battery module increases the stress on the battery cells 11 within the battery module. If multiple junction boxes 20 are perfectly aligned in the same direction within the battery assembly 100, significant stress concentration can easily occur in localized areas, thereby increasing the risk of microcracks in the battery cells 11 within the battery module. In this embodiment of the invention, by staggering at least two junction boxes 20 along a second direction, the stress distribution of each junction box 20 on the battery module will no longer completely overlap, thus distributing the stress more evenly throughout the entire battery module. This effectively reduces stress concentration in the battery module, lowers the risk of microcracks and fragmentation of the battery cells 11 within the battery module, and improves the stability and reliability of the battery assembly 100.

[0077] It is understandable that placing the junction box 20 in the battery module increases the heat borne by the battery cells 11 within the battery module. If multiple junction boxes 20 are perfectly aligned in the same direction within the battery assembly 100, significant heat can easily be generated in localized areas, thereby increasing the temperature of the battery cells 11 and the hot spots generated by the battery module. In this embodiment of the invention, by staggering at least two junction boxes 20 along the second direction, the heat generated by each junction box 20 is no longer completely superimposed, thus distributing the heat more evenly throughout the battery module. This reduces heat concentration in the battery module, thereby reducing hot spots in the battery assembly 100, increasing the efficiency of the battery assembly 100, and extending the lifespan of the battery assembly 100.

[0078] Furthermore, such as Figure 8 As shown, at least two of the multiple junction boxes 20 have a first spacing K1 in the second direction, where the first spacing K1 is between 10mm and 500mm. For example, it can be 10mm, 30mm, 50mm, 60mm, 100mm, 150mm, 200mm, 300mm, 400mm, or 500mm. It can be understood that the spacing between two offset junction boxes 20 cannot be less than 10mm. When the first spacing K1 is less than 10mm, the two offset junction boxes 20 will not be completely offset in the second direction, thus failing to effectively distribute stress and heat concentration in each junction box 20. The spacing between two offset junction boxes 20 cannot be greater than 500mm. When the first spacing K1 is greater than 10mm, the wiring complexity between the junction box 20 and the battery module is too high, thereby increasing the cost of the battery assembly 100.

[0079] It is understandable that the first spacing K1 refers to the minimum distance between the two junction boxes 20 in the second direction. That is, the distance between the edges of the two junction boxes 20 closest to each other in the second direction.

[0080] For example, such as Figure 14 As shown, the plurality of junction boxes 20 include a first junction box 21 and a second junction box 22, with a first distance K1 between the first junction box 21 and the second junction box 22 in a second direction. The first junction box 21 has a fifth edge 211 and a sixth edge 212 arranged along the second direction, with the fifth edge 211 being closer to the second junction box 22 in the second direction than the sixth edge 212. The second junction box 22 has a seventh edge 221 and an eighth edge 222 arranged along the second direction, with the seventh edge 221 being closer to the first junction box 21 in the second direction than the eighth edge 222. The second distance K2 between the first junction box 21 and the second junction box 22 refers to the distance between the fifth edge 211 and the seventh edge 221 in the second direction.

[0081] Furthermore, such as Figure 9 As shown, at least two of the multiple junction boxes 20 have a second spacing K2 in a second direction, the second spacing K2 being 60mm to 100mm. For example, it is 60mm, 70mm, 80mm, 90mm, or 100mm. In this way, the junction boxes can be completely staggered without excessively increasing the wiring complexity between the junction boxes 20 and the battery module, thus avoiding excessively high costs for the battery assembly 100.

[0082] It is understandable that the second spacing K2 refers to the minimum distance between the two junction boxes 20 in the second direction, that is, the distance between the edges of the two junction boxes 20 that are close to each other in the second direction.

[0083] like Figure 15 As shown, for example, a plurality of junction boxes 20 include a first junction box 21 and a second junction box 22, with a second distance K2 between the first junction box 21 and the second junction box 22 in a second direction. The first junction box 21 has a fifth edge 211 and a sixth edge 212 arranged along the second direction, with the fifth edge 211 being closer to the second junction box 22 in the second direction than the sixth edge 212. The second junction box 22 has a seventh edge 221 and an eighth edge 222 arranged along the second direction, with the seventh edge 221 being closer to the first junction box 21 in the second direction than the eighth edge 222. The second distance K2 between the first junction box 21 and the second junction box 22 refers to the distance between the fifth edge 211 and the seventh edge 221 in the second direction.

[0084] Of course, such as Figure 10 and Figure 11 As shown, in other embodiments, all junction boxes 20 in the plurality of junction boxes 20 may be staggered from each other in the second direction.

[0085] In this way, the stress distribution of each junction box 20 on the battery module will be completely staggered, thereby further dispersing the stress borne by the battery module, increasing the bending stress that the middle area of ​​the battery assembly 100 can withstand, and further reducing stress concentration in the battery module. This can reduce the risk of microcracks and fragmentation of the battery cells 11 in the battery module, and improve the stability and reliability of the battery assembly 100. At the same time, the heat generated by each junction box 20 can also be further dispersed, thereby reducing heat concentration in the battery module, reducing hot spots in the battery assembly 100, increasing the efficiency of the battery assembly 100, and extending the life of the battery assembly 100.

[0086] Furthermore, all the junction boxes 20 in the plurality of junction boxes 20 are staggered from each other in the second direction, and any two junction boxes 20 have a third spacing K3 in the second direction, the third spacing K3 being 10mm to 500mm. For example, 10mm, 30mm, 50mm, 60mm, 100mm, 150mm, 200mm, 300mm, 400mm, and 500mm. It can be understood that the spacing between two staggered junction boxes 20 cannot be less than 10mm. When the third spacing K3 is less than 10mm, the two staggered junction boxes 20 will not be completely staggered in the second direction, thus failing to effectively distribute the stress concentration and heat concentration of each junction box 20; the spacing between two staggered junction boxes 20 cannot be greater than 500mm. When the third spacing K3 is greater than 10mm, the wiring complexity between the junction box 20 and the battery module is too high, thereby increasing the cost of the battery assembly 100.

[0087] It is understandable that the third spacing K3 refers to the minimum distance between the two junction boxes 20 in the second direction, that is, the distance between the edges of the two junction boxes 20 that are close to each other in the second direction.

[0088] like Figure 16 As shown, for example, a plurality of junction boxes 20 include a first junction box 21 and a second junction box 22, with a third distance K3 between the first junction box 21 and the second junction box 22 in a second direction. The first junction box 21 has a fifth edge 211 and a sixth edge 212 arranged along the second direction, with the fifth edge 211 being closer to the second junction box 22 in the second direction than the sixth edge 212. The second junction box 22 has a seventh edge 221 and an eighth edge 222 arranged along the second direction, with the seventh edge 221 being closer to the first junction box 21 in the second direction than the eighth edge 222. The third distance K3 between the first junction box 21 and the second junction box 22 refers to the distance between the fifth edge 211 and the seventh edge 221 in the second direction.

[0089] Furthermore, at least two of the multiple junction boxes 20 have a fourth spacing K4 in the second direction, the fourth spacing K4 being 60mm to 100mm. For example, it is 60mm, 70mm, 80mm, 90mm, or 100mm. In this way, while completely offsetting the junction boxes 20, the wiring complexity between the junction boxes 20 and the battery module is not excessively increased, thus avoiding excessively high costs for the battery assembly 100.

[0090] It is understandable that the fourth spacing K4 refers to the minimum distance between the two junction boxes 20 in the second direction, that is, the distance between the edges of the two junction boxes 20 that are close to each other in the second direction.

[0091] like Figure 17 As shown, for example, a plurality of junction boxes 20 include a first junction box 21 and a second junction box 22, with a fourth distance K4 between the first junction box 21 and the second junction box 22 in a second direction. The first junction box 21 has a fifth edge 211 and a sixth edge 212 arranged along the second direction, with the fifth edge 211 being closer to the second junction box 22 in the second direction than the sixth edge 212. The second junction box 22 has a seventh edge 221 and an eighth edge 222 arranged along the second direction, with the seventh edge 221 being closer to the first junction box 21 in the second direction than the eighth edge 222. The fourth distance K4 between the first junction box 21 and the second junction box 22 refers to the distance between the fifth edge 211 and the seventh edge 221 in the second direction.

[0092] like Figure 6As shown, in one possible implementation, the battery assembly 100 includes a first edge 102 and a second edge 103 arranged along a second direction, both extending along the first direction. Specifically, the battery assembly 100 has a first edge 102 and a second edge 103 extending along the first direction, the first edge 102 and the second edge 103 being two boundary lines of the battery assembly 100 in the second direction.

[0093] Furthermore, in the second direction, the distance between the junction box 20 and the first edge 102 is a fifth distance K5, and the distance between the junction box 20 and the second edge 103 is a sixth distance K6, where the fifth distance K5 is not equal to the sixth distance K6. In this way, the junction box 20 can be shifted away from the central part of the battery assembly 100 where stress is high, thereby reducing the stress on the battery cells 11 in the central part of the battery assembly 100, thus reducing the risk of microcracks and fragmentation of the battery cells 11, and extending the lifespan of the battery assembly 100. Simultaneously, shifting the junction box 20 away from the central part of the battery assembly 100 where heat is high can also reduce heat concentration in the central part of the battery assembly 100, thereby reducing hot spots in the battery assembly 100, increasing the efficiency of the battery assembly 100, and extending the lifespan of the battery assembly 100.

[0094] It is understandable that the fifth spacing K5 refers to the minimum distance between the junction box 20 and the first edge 102 in the second direction. That is, the distance between the edge of the junction box 20 facing the first edge 102 and the first edge 102 in the second direction.

[0095] It is understandable that the sixth spacing K6 refers to the minimum distance between the junction box 20 and the second edge 103 in the second direction. That is, the distance between the edge of the junction box 20 facing the second edge 103 and the second edge 103 in the second direction.

[0096] It is understandable that the fifth spacing K5 is not equal to the sixth spacing K6. This means that, for each junction box 20, in the second direction, the distance from the junction box 20 to the first edge 102 is greater or less than the distance from the junction box 20 to the second edge 103. This allows each junction box 20 to have a certain offset relative to the center line 101 of the battery assembly 100 in the second direction. This ensures that each junction box 20 is completely removed from the high-stress and high-heat areas near the center line 101 of the battery assembly 100, thereby improving the efficiency of the battery assembly 100 and extending its service life.

[0097] The fifth spacing, K5, ranges from 600mm to 1500mm. Examples include 600mm, 700mm, 800mm, 900mm, 1000mm, 1100mm, 1200mm, and 1300mm. The sixth spacing, K6, can be 700mm, 800mm, 900mm, 1000mm, 1100mm, 1200mm, 1300mm, and 1500mm.

[0098] Specifically, the configuration method for each junction box 20 is as follows: Figure 6 As shown, the fifth spacing K5 of all junction boxes 20 in a plurality of junction boxes 20 can be set to be greater than the sixth spacing K6; or, it can be done as follows: Figure 7 As shown, the fifth spacing K5 of all junction boxes 20 in the plurality of junction boxes 20 is greater than the sixth spacing K6; or, it can be as follows: Figure 5 As shown, in some of the multiple junction boxes 20, the fifth spacing K5 is greater than the sixth spacing K6, and in another portion of the multiple junction boxes 20, the sixth spacing K6 is greater than the fifth spacing K5. No further limitations are imposed here.

[0099] In one possible implementation, such as Figure 5 As shown, the plurality of junction boxes 20 include a first junction box 21 and a second junction box 22; the first junction box 21 and the second junction box 22 are respectively located on both sides of the center line 101 in the second direction, and the distance K7 between the first junction box 21 and the second junction box 22 in the second direction is less than or equal to 200mm. For example, it is 20mm, 30mm, 50mm, 60mm, 70mm, 80mm, 90mm, 100mm, 120mm, 150mm, 180mm, or 200mm.

[0100] The distance K7 between the first junction box 21 and the second junction box 22 in the second direction refers to the minimum distance between the two junction boxes 20 in the second direction, that is, the distance between the edges of the two junction boxes 20 that are close to each other in the second direction.

[0101] like Figure 18 As shown, the first junction box 21 has a fifth edge 211 and a sixth edge 212 arranged along the second direction, with the fifth edge 211 being closer to the second junction box 22 in the second direction than the sixth edge 212. The second junction box 22 has a seventh edge 221 and an eighth edge 222 arranged along the second direction, with the seventh edge 221 being closer to the first junction box 21 in the second direction than the eighth edge 222. The distance K7 between the first junction box 21 and the second junction box 22 in the second direction refers to the distance between the fifth edge 211 and the seventh edge 221 in the second direction.

[0102] This reduces heat buildup near the center line 101 of the battery module 100, preventing excessive heat concentration in the middle part of the battery module 100 and helping to extend its service life. Furthermore, it further disperses the stress distribution of each junction box 20 on the battery module, making the stress more evenly distributed throughout the entire battery module. This effectively reduces stress concentration in the battery module, lowers the risk of microcracks and fragmentation of the battery cells 11, and improves the stability and reliability of the battery module 100.

[0103] It can be understood that the distance K7 between the first junction box 21 and the second junction box 22 in the second direction cannot be greater than 200mm. When the distance K7 between the first junction box 21 and the second junction box 22 in the second direction is greater than 200mm, it will lead to excessive wiring complexity between the junction box 20 and the battery module, thereby increasing the cost of the battery assembly 100.

[0104] like Figure 5 As shown, further, the plurality of junction boxes 20 include a first junction box 21, a second junction box 22, and a third junction box 23. Exemplarily, the first junction box 21 and the second junction box 22 can be located on one side of the center line 101 in the second direction, and the third junction box 23 can be located on the other side of the center line 101 in the second direction. Alternatively, the second junction box 22 and the third junction box 23 can be located on one side of the center line 101 in the second direction, and the first junction box 21 can be located on the other side of the center line 101 in the second direction. Or, the first junction box 21 and the third junction box 23 can be located on one side of the center line 101 in the second direction, and the second junction box 22 can be located on the other side of the center line 101 in the second direction. No limitation is made here.

[0105] It is understood that in such embodiments, the battery assembly 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 surfaces of the back contact cells, the photovoltaic glass, adjacent back contact cells, etc. 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.

[0106] Photovoltaic glass can be applied to the encapsulating film on the front side of the back contact battery. 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 back contact battery while minimizing impact on its efficiency. Simultaneously, the encapsulating film bonds the photovoltaic glass and the back contact battery together, providing sealing, insulation, and waterproofing / moisture protection for the battery.

[0107] The backsheet can be attached to the adhesive film on the back side of the back contact battery. The backsheet protects and supports the back contact battery, providing reliable insulation, water resistance, and aging resistance. Multiple options are available for the backsheet, typically tempered glass, acrylic glass, aluminum alloy TPT composite adhesive film, etc., and the specific choice depends on the specific circumstances and is not limited here. The backsheet, back contact battery, adhesive film, and photovoltaic glass can be integrated into a frame. The frame serves as the main external support structure for the entire battery module 100, providing stable support and installation for the battery module 100. For example, the battery module 100 can be installed at the desired location via the frame.

[0108] In the description of this specification, 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 the present invention. 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.

[0109] Furthermore, the above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A battery assembly, comprising: The battery assembly includes a battery module and a plurality of junction boxes electrically connected to the battery module. The battery module includes a plurality of battery strings arranged along a first direction, and each battery string includes a plurality of battery cells arranged along a second direction. The first direction and the second direction intersect. The centerline of the battery assembly is spaced from the junction box in the second direction, and the centerline extends along the first direction.

2. The battery assembly of claim 1, wherein, The distance between the junction box and the center line in the second direction is 30mm to 100mm.

3. The battery assembly of claim 1, wherein, The distance between the junction box and the center line in the second direction is D1, and the dimension of the battery cell in the second direction is D2; 0.2·D2<D1<3·D2.

4. The battery assembly of claim 1, wherein, Each of the junction boxes is arranged collinearly in the first direction.

5. The battery assembly according to claim 1, characterized in that, At least two of the plurality of junction boxes have a first spacing in the second direction, the first spacing being 10m to 500mm.

6. The battery assembly of claim 5, wherein, At least two of the plurality of junction boxes have a second spacing in the second direction, the second spacing being 60 mm to 100 mm.

7. The battery assembly of claim 5, wherein, All of the junction boxes in the plurality of junction boxes are staggered from each other in the second direction, and any two junction boxes have a third distance in the second direction, the third distance being 10m to 500mm.

8. The battery assembly according to claim 7, characterized in that, All of the junction boxes in the plurality of junction boxes are staggered from each other in the second direction, and any two junction boxes have a fourth spacing in the second direction, the fourth spacing being 60mm to 100mm.

9. The battery assembly of claim 2, wherein, The plurality of junction boxes includes a first junction box and a second junction box; the first junction box and the second junction box are respectively disposed on both sides of the center line in the second direction, and the distance between the first junction box and the second junction box in the second direction is less than or equal to 200mm.

10. The battery assembly according to claim 1, characterized in that, The battery assembly includes a first edge and a second edge arranged along the second direction, both the first edge and the second edge extending along the first direction. The distance between the junction box and the first edge is a fifth distance, and the distance between the junction box and the second edge is a sixth distance. The fifth distance is not equal to the sixth distance.

11. The battery assembly according to claim 10, characterized in that, The fifth spacing is 600mm to 1500mm.

12. A photovoltaic system, characterized in that, The photovoltaic system includes a battery module as described in any one of claims 1 to 11.

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