Battery assembly and photovoltaic system

Abstract

The application is suitable for the photovoltaic technical field, and provides a battery assembly and a photovoltaic system.The battery assembly comprises a first battery piece and a second battery piece arranged in sequence along a first direction, the first battery piece and the second battery piece are partially overlapped to form a first overlapping area, and a third battery piece is arranged.The application eliminates the piece spacing by partially overlapping a plurality of battery pieces, and the local height of the overlapping area of the plurality of battery pieces is gradient designed, stress is dispersed through gradient transition, laminating pressure is dispersed, the stress concentration problem of the overlapping area in the battery piece laminating process is solved, the risk of hidden cracking of the battery piece is effectively reduced, the height design of the multi-level battery piece makes the laminated structure of the battery assembly more stable, the connection between the battery pieces is fastened after the battery assembly is packaged, the reliability is high, through the structural arrangement of the application, the overall appearance of the battery assembly is better, and the production efficiency is improved.

Description

Technical Field

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

[0002] Currently, there is a gap between adjacent cells in conventional battery modules, and a gap between adjacent strings. The existence of these gaps not only limits the power generation per unit area of ​​the battery module but also causes light leakage. Therefore, reducing the gap between cells and strings, or even eliminating the gap between cells and strings completely, is an industry trend. Utility Model Content

[0003] This application provides a battery module designed to address the issue of spacing between adjacent cells and between adjacent battery strings in conventional battery modules. These spacings not only limit the power generation per unit area of ​​the battery module but also cause light leakage.

[0004] This application is implemented as follows: a battery assembly includes a first battery cell and a second battery cell arranged sequentially along a first direction, the first battery cell and the second battery cell partially overlapping to form a first overlapping region, and a third battery cell, the third battery cell partially overlapping with the first battery cell in a second direction to form a second overlapping region. In the first overlapping region, the local height of the second battery cell is greater than the local height of the first battery cell, and in the second overlapping region, the local height of the third battery cell is greater than the local height of the first battery cell.

[0005] Optionally, the local height of the third battery cell within the second overlapping region is equal to the local height of the second battery cell within the first overlapping region.

[0006] Optionally, the battery assembly further includes a fourth battery cell, which partially overlaps with the third battery cell along the first direction to form a third overlapping region, wherein the local height of the fourth battery cell is greater than the local height of the third battery cell within the third overlapping region.

[0007] Optionally, the fourth battery cell partially overlaps with the second battery cell along the second direction to form a fourth overlapping region, wherein the local height of the fourth battery cell is greater than the local height of the second battery cell within the fourth overlapping region.

[0008] Optionally, the fourth battery cell partially overlaps with the second battery cell along the second direction to form a fourth overlapping region, wherein the local height of the fourth battery cell is less than the local height of the second battery cell within the fourth overlapping region.

[0009] Optionally, the first and second battery cells partially overlap along the first direction to form a first battery string, and the third and fourth battery cells partially overlap along the first direction to form a second battery string.

[0010] Optionally, the first battery string and the second battery string are partially overlapped along the second direction.

[0011] Optionally, the first battery cell, the second battery cell, the third battery cell, and the fourth battery cell enclose a closed area.

[0012] Optionally, the projection of the enclosed region in a third direction is a triangle or a rhombus.

[0013] Optionally, a portion of the first battery cell has a first height in the first overlapping region, and a portion of the second battery cell has a second height in the first overlapping region, wherein the difference between the first height and the second height is in the range of 100 to 200 micrometers.

[0014] Optionally, the first battery cell has the first height in the second overlapping region, and a portion of the third battery cell has a third height in the second overlapping region, wherein the difference between the third height and the first height is in the range of 100 to 200 micrometers.

[0015] Optionally, the third height is equal to the second height.

[0016] Optionally, a portion of the third battery cell has a fourth height in the third overlapping region, and the fourth battery cell has a fifth height in the third overlapping region, wherein the difference between the fifth height and the fourth height is in the range of 100 to 200 micrometers.

[0017] Optionally, the difference between the fifth height and the first height is in the range of 200 to 400 micrometers.

[0018] Optionally, a portion of the second solar cell has a sixth height in the fourth overlapping region, and a portion of the fourth solar cell has a seventh height in the fourth overlapping region, wherein the difference between the sixth height and the seventh height is in the range of 100 to 200 micrometers.

[0019] Optionally, when the seventh height is greater than the sixth height, the difference between the seventh height and the first height is in the range of 200 to 400 micrometers.

[0020] Optionally, when the seventh height is less than the sixth height, the seventh height and the first height are equal.

[0021] Optionally, each of the first, second, third, and fourth battery cells includes a chamfered edge and a cut edge without chamfering, the chamfered edge and the cut edge being opposite each other.

[0022] Optionally, along the first direction, the cut edge of the first battery cell and the chamfered edge of the second battery cell overlap.

[0023] Optionally, along the first direction, the chamfered edges of the first battery cell and the chamfered edges of the second battery cell overlap.

[0024] Optionally, along the first direction, the cut edge of the third battery cell and the chamfered edge of the fourth battery cell overlap.

[0025] Optionally, along the first direction, the chamfered edges of the third and fourth battery cells overlap.

[0026] This application eliminates inter-cell spacing by partially overlapping multiple solar cells and designs a gradient in the height of the overlapping area. This gradient transition disperses stress and lamination pressure, thus solving the stress concentration problem in the overlapping area during the solar cell lamination process. This effectively reduces the risk of microcracks in the solar cells. Furthermore, the height design of the multi-layered solar cells makes the stacked structure of the solar module more stable. After the solar module is encapsulated, the connection between the solar cells is tight, resulting in high reliability. The structural design of this application also improves the overall aesthetics of the solar module and helps to improve production efficiency. Attached Figure Description

[0027] Figure 1 This is a structural schematic diagram of the first type of battery assembly provided in the current application;

[0028] Figure 2 This is a structural schematic diagram of the second type of battery assembly provided in the current application.

[0029] Explanation of reference numerals in the attached figures:

[0030] 100, First solar cell; 101, First overlapping region; 200, Second solar cell; 300, Third solar cell; 400, Fourth solar cell; 500, First solar cell string; 600, Second solar cell string; 101, First overlapping region; 201, Second overlapping region; 301, Third overlapping region; 401, Fourth overlapping region; 700, Closed region. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit this application.

[0032] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0033] 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 application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0034] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0035] In this application, unless otherwise expressly 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 being 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 being 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.

[0036] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. 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 this application. 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, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0037] like Figure 1 and Figure 2 As shown, in some embodiments, a battery assembly includes a first battery cell 100 and a second battery cell 200 arranged sequentially along a first direction, and a third battery cell 300 and a fourth battery cell 400 arranged sequentially along the first direction.

[0038] The first battery cell 100 and the second battery cell 200, which are sequentially overlapped along the first direction, can be connected in series to form a first battery string 500. The first battery string 500 may include two, three, or more battery cells connected in series. The specific number of battery cells to be connected in series can be determined according to the actual usage, and this application does not impose any restrictions on this. Similarly, the third battery cell 300 and the fourth battery cell 400, which are sequentially overlapped along the first direction, can also be connected in series to form a second battery string 600. The second battery string 600 may include two, three, or more battery cells connected in series. The specific number of battery cells to be connected in series can be determined according to the actual usage, and this application does not impose any restrictions on this. Furthermore, the above-mentioned battery assembly may include two, three, or more battery strings. Multiple battery strings can be connected in series or in parallel. The specific number of battery strings and the connection method can be determined according to the actual usage, and this application does not impose any restrictions on this.

[0039] In this embodiment, a combination of at least four battery cells is used as the basic unit to describe the overlapping pattern between the battery cells. In practice, the battery assembly may include a fifth, sixth, or more battery cells. The overlapping pattern between the remaining battery cells can refer to the overlapping pattern of the four battery cells within the basic unit. Furthermore, in this embodiment, the first battery cell 100 can be set as the end battery cell of the first battery string 500, and the remaining battery cells arranged within the first battery string 500 can be sequentially overlapped along the first direction. Similarly, the third battery cell 300 can be set as the end battery cell of the second battery string 600, and the remaining battery cells arranged within the second battery string 600 can be sequentially overlapped along the first direction. As for the overlapping pattern between the first battery string 500 and the second battery string 600, it can refer to the overlapping pattern of the two sets of battery strings within the basic unit. The height between the battery cells varies accordingly for different overlapping patterns.

[0040] It is understood that the grid lines on the solar cells described above are not shown in the accompanying drawings. The grid lines on the solar cells can be arranged according to actual conditions; for example, they can be solar cells with main grids or those without. The type of solar cell can be a back-contact cell, that is, all electrodes (positive and negative) are located on the back of the cell, with no metal grid lines obstructing the front, maximizing light absorption. An example is an IBC (Interdigitated Back Contact) cell. The type of solar cell can also be a bifacial cell, that is, both the front and back can receive light and generate electricity, with the back gaining power through reflected light or ambient light. Examples include PERC bifacial, TOPCon bifacial, and HJT bifacial cells. This application does not impose any limitations on this.

[0041] Furthermore, the first battery cell 100 and the second battery cell 200 are partially overlapped to form a first overlap region 101, constituting a partial overlap within the same battery string. The third battery cell 300 is partially overlapped with the first battery cell 100 in a second direction to form a second overlap region 201, constituting a partial overlap between the third battery cell 300 and the first battery cell 100 within the same battery string. Within the first overlap region 101, the local height of the second battery cell 200 is greater than the local height of the first battery cell 100. Within the second overlap region 201, the local height of the third battery cell 300 is greater than the local height of the first battery cell 100. It is understood that in this embodiment, the heights of each battery cell are compared with the same plane as a reference reference; for example, the backplane glass in the battery assembly can be used as a reference reference. Furthermore, the height of each battery cell is formed by comparing its respective surface. For example, the height comparison of the first battery cell 100 and the second battery cell 200 can be a comparison of the height of the light-receiving surface of the first battery cell 100 and the second battery cell 200, or a comparison of the height of the backlight surface of the first battery cell 100 and the second battery cell 200. The local height comparison of each battery cell within the overlapping area is performed along the thickness direction of the battery cells, forming a staggered overlapping pattern between the battery cells.

[0042] This application eliminates inter-cell spacing by partially overlapping multiple solar cells and designs a gradient in the height of the overlapping area. This gradient transition disperses stress and lamination pressure, thus solving the stress concentration problem in the overlapping area during the solar cell lamination process. This effectively reduces the risk of microcracks at the cell edges. Furthermore, the height design of the multi-layered solar cells makes the stacked structure of the solar module more stable. After the solar module is encapsulated, the connection between the cells is tight, resulting in high reliability. The structural design of this application also improves the overall aesthetics of the solar module and helps to improve production efficiency.

[0043] In this embodiment, the second direction intersects the first direction. Specifically, the second direction can be perpendicular to the first direction. For example, the first direction can be the width direction of the battery cell, and the second direction can be the length direction of the battery cell.

[0044] In some embodiments, the local height of the third battery cell 300 within the second overlapping region 201 is equal to the local height of the second battery cell 200 within the first overlapping region 101. In the above-described battery module layout, the first battery cell 100 is at the lowest position and simultaneously supports the second battery cell 200 and the third battery cell 300. By having the third battery cell 300 and the second battery cell 200 overlap at the same height on the first battery cell 100, the overlapping region becomes a point of mechanical stress concentration during the module lamination process. The symmetrical height design allows the stress to be evenly distributed between the two overlapping areas, avoiding micro-cracks or delamination at the edge of the battery cell (such as interface peeling between the EVA encapsulation material and the battery cell) caused by excessive height difference on one side.

[0045] In some embodiments, the fourth solar cell 400 partially overlaps with the third solar cell 300 along a first direction to form a third overlapping region 301. Within the third overlapping region 301, the local height of the fourth solar cell 400 is greater than the local height of the third solar cell 300. The partial overlap of the fourth solar cell 400 and the third solar cell 300 constitutes the second battery string 600. This arrangement allows for the same overlap pattern as the solar cells in the first battery string 500 described above. In other words, the first battery string 500 and the second battery string 600 can be battery strings of the same design, which simplifies the manufacturing process in module production.

[0046] In other embodiments, the width of the overlapping area between multiple battery cells within the same battery string in the first direction can be entirely or partially equal. For example, the width of the overlapping area can be between 0.5 and 1.5 mm. Specifically, the width of the overlapping area can be set as needed. Further, adjacent battery strings overlap along a second direction. For example, the first battery string 500 and the second battery string 600 partially overlap along the second direction. The width of the overlapping area between the battery strings can also be set between 0.5 and 1.5 mm. Preferably, the overlapping areas between the battery strings are set to be equal to facilitate component layout.

[0047] In some embodiments, the fourth battery cell 400 partially overlaps with the second battery cell 200 along the second direction to form a fourth overlapping region 401. Within the fourth overlapping region 401, the local height of the fourth battery cell 400 is greater than the local height of the second battery cell 200. Thus, the local overlap pattern between the fourth battery cell 400 and the second battery cell 200 is the same as the local overlap pattern between the third battery cell 300 and the first battery cell 100. In other words, the local overlap pattern between the battery cells in the two sets of battery strings is consistent, which is beneficial for the layout and arrangement of the components.

[0048] In some embodiments, the fourth battery cell 400 partially overlaps with the second battery cell 200 along the second direction to form a fourth overlapping region 401. Within the fourth overlapping region 401, the local height of the fourth battery cell 400 is less than the local height of the second battery cell 200. This interleaved stacking of the four battery cells creates a more robust stacked structure, resulting in a tighter connection between the battery cells after the battery assembly is encapsulated, leading to high reliability.

[0049] In some embodiments, the first solar cell 100, the second solar cell 200, the third solar cell 300, and the fourth solar cell 400 enclose a closed region 700. By partially overlapping multiple solar cells to eliminate inter-cell spacing, more solar cells can be arranged within a limited area, improving space utilization and module power generation. No new process steps or equipment modifications are required in the manufacturing process; simply changing the stacking method of the solar cells using existing production equipment can achieve negative spacing between cells. The formation of the closed region not only improves light leakage in the solar module but also facilitates the utilization of light within the cell string spacing, improving the power generation efficiency of the photovoltaic module. Through the structural design of this application, the overall aesthetics of the photovoltaic module are improved, which is beneficial for increasing production efficiency.

[0050] Furthermore, the projection of the closed region 700 in a third direction is a triangle or a rhombus. The closed region 700 originates from the closed porous structure formed by at least four solar cells within the battery module, and the size of the overlapping area between the solar cells is directly related to the size of the closed region. A well-defined closed region not only improves the appearance of the battery module but also facilitates the control and adjustment of the closed region area.

[0051] In some embodiments, a portion of the first battery cell 100 has a first height in the first overlapping region 101, and a portion of the second battery cell 200 has a second height in the first overlapping region 101. The difference between the first height and the second height ranges from 100 to 200 micrometers. Specifically, the second height is greater than the first height. In such embodiments, the difference between the second height and the first height can be any value between 100 micrometers, 110 micrometers, 120 micrometers, 140 micrometers, 160 micrometers, 180 micrometers, 200 micrometers, or 100 to 200 micrometers, without any specific limitation. It is understood that within such a height difference range, the height difference between the first battery cell 100 and the second battery cell 200 can be the thickness of one battery cell or greater than the thickness of the battery cell. For example, a conductive film layer or an insulating film layer is provided in the overlapping region of the battery cells.

[0052] The first battery cell 100 has a first height in the second overlapping region 201, and a portion of the third battery cell 300 has a third height in the second overlapping region 201. The difference between the third height and the first height ranges from 100 to 200 micrometers. Specifically, the third height is greater than the first height. In such an embodiment, the difference between the third height and the first height can be any value between 100 micrometers, 110 micrometers, 120 micrometers, 140 micrometers, 160 micrometers, 180 micrometers, 200 micrometers, or 100 to 200 micrometers, without any specific limitation. It can be understood that within such a height difference range, the height difference between the third battery cell 300 and the first battery cell 100 can be the thickness of one battery cell or greater than the thickness of the battery cell. For example, a conductive film layer or an insulating film layer is provided in the overlapping region of the battery cells.

[0053] In some embodiments, the third height and the second height are equal. In the above-described battery module layout, the first battery cell 100 is at the lowest position, and the first battery cell 100 simultaneously supports the second battery cell 200 and the third battery cell 300. By having the third battery cell 300 and the second battery cell 200 overlap at the same height on the first battery cell 100, the resulting third height and second height are equal. During the module lamination process, the overlapping area is a point of concentration of mechanical stress. The symmetrical height design allows the stress to be evenly distributed at the two overlapping areas, avoiding micro-cracks or delamination at the edge of the battery cell (such as interface peeling between the EVA encapsulation material and the battery cell) caused by excessive height difference on one side.

[0054] In some embodiments, a portion of the third battery cell 300 has a fourth height in the third overlapping region 301, and the fourth battery cell 400 has a fifth height in the third overlapping region 301. The difference between the fifth height and the fourth height ranges from 100 to 200 micrometers. Specifically, the fifth height is greater than the fourth height. In such embodiments, the difference between the fifth height and the fourth height can be any value between 100 micrometers, 110 micrometers, 120 micrometers, 140 micrometers, 160 micrometers, 180 micrometers, 200 micrometers, or 100 to 200 micrometers, without any specific limitation. It is understood that within such a height difference range, the height difference between the fourth battery cell 400 and the third battery cell 300 can be the thickness of one battery cell or greater than the thickness of the battery cell. For example, a conductive film layer or an insulating film layer is provided in the overlapping region of the battery cells.

[0055] In some embodiments, the difference between the fifth height and the first height ranges from 200 to 400 micrometers. In such embodiments, the difference between the fifth height and the first height can be any value between 200 micrometers, 210 micrometers, 220 micrometers, 240 micrometers, 360 micrometers, 380 micrometers, 400 micrometers, or 200 to 400 micrometers, without any specific limitation. It can be understood that within such a height difference range, the height difference between the fourth battery cell 400 and the first battery cell 100 can be the thickness of the two battery cells or greater than the thickness of the two battery cells. For example, a conductive film layer or an insulating film layer is provided in the overlapping area between the battery cells.

[0056] In some embodiments, a portion of the second solar cell 200 has a sixth height in the fourth overlapping region 401, and a portion of the fourth solar cell 400 has a seventh height in the fourth overlapping region 401. The difference between the sixth and seventh heights ranges from 100 to 200 micrometers. Specifically, the sixth height can be greater than or less than the seventh height, and the difference between the sixth and seventh heights is the range of the absolute values ​​of their differences. The relative sizes of the sixth and seventh heights are determined based on the specific overlapping configuration of the second and fourth solar cells 200.

[0057] In some embodiments, when the seventh height is greater than the sixth height, the difference between the seventh height and the first height ranges from 200 to 400 micrometers. In such embodiments, the difference between the seventh height and the first height can be any value between 200 micrometers, 210 micrometers, 220 micrometers, 240 micrometers, 360 micrometers, 380 micrometers, 400 micrometers, or 200 to 400 micrometers, without any specific limitation. It can be understood that within such a height difference range, the height difference between the fourth battery cell 400 and the first battery cell 100 can be the thickness of the two battery cells or greater than the thickness of the two battery cells. For example, a conductive film layer or an insulating film layer is provided in the overlapping area between the battery cells.

[0058] In some embodiments, when the seventh height is less than the sixth height, the seventh height and the first height are equal. The four solar cells form a cross-laminated structure, which is more stable, resulting in a reliable and stable module structure.

[0059] In some embodiments, each of the first battery cell 100, the second battery cell 200, the third battery cell 300, and the fourth battery cell 400 includes a chamfered edge and a cut edge without chamfering, with the chamfered edge and the cut edge facing each other. The aforementioned battery cells in this application can be half-cells obtained by dicing a whole battery cell, where the chamfered edge is the non-cut edge, the right-angled edge is the cut edge, the chamfered edge of the half-cell is the chamfered edge of the whole battery cell, and the right-angled edge of the half-cell is the cut edge formed by dicing the whole battery cell.

[0060] In some embodiments, along the first direction, the cut edge of the first battery cell 100 and the chamfered edge of the second battery cell 200 overlap. Further, viewed from the light-receiving surface of the battery cell, the cut edge of the first battery cell 100 may be stacked above the chamfered edge of the second battery cell 200, or the chamfered edge of the second battery cell 200 may be stacked above the cut edge of the first battery cell 100. In this way, adjacent battery cells overlap with both the chamfered edge and the cut edge. By ensuring consistency in the overlapping method of each battery cell, the stacking process can be simplified.

[0061] In some embodiments, along a first direction, the chamfered edges of the first solar cell 100 and the second solar cell 200 overlap. Understandably, in this overlapping configuration, the cut edges of the first solar cell 100 and the second solar cell 200 overlap, ensuring that the overlapping areas of adjacent solar cells are consistent during module lamination. This effectively disperses the lamination pressure between the overlapping areas of adjacent solar cells, reducing the risk of microcracks at the cell edges.

[0062] In some embodiments, along the first direction, the cut edge of the third battery cell 300 and the chamfered edge of the fourth battery cell 400 overlap. Further, viewed from the light-receiving surface of the battery cell, the cut edge of the third battery cell 300 may be stacked above the chamfered edge of the fourth battery cell 400, or the chamfered edge of the fourth battery cell 400 may be stacked above the cut edge of the third battery cell 300. In this way, adjacent battery cells overlap with both the chamfered and cut edges. By ensuring consistency in the overlapping method of each battery cell, the stacking process can be simplified.

[0063] In some embodiments, the chamfered edges of the third solar cell 300 and the fourth solar cell 400 overlap along the first direction. Understandably, in this overlapping configuration, the cut edges of the third solar cell 300 and the fourth solar cell 400 overlap, ensuring that the overlapping areas of adjacent solar cells are consistent during module lamination. This effectively disperses the lamination pressure between the overlapping areas of adjacent solar cells, reducing the risk of microcracks at the cell edges.

[0064] A photovoltaic system includes the aforementioned battery modules. In this embodiment, the photovoltaic system can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants, and can also be applied to equipment or devices that utilize solar energy to generate electricity, 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 are not limited to these; that is, the photovoltaic system can be applied in all fields that require solar energy to generate electricity. Taking a photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array may be an array combination of multiple battery modules; for example, multiple battery modules 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.

[0065] In the description of this specification, the use of terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., refers to specific features, structures, materials, or characteristics described in connection with the embodiments or examples, which are 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 embodiments or examples. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0066] 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, The device includes a first battery cell and a second battery cell arranged sequentially along a first direction, wherein the first battery cell and the second battery cell partially overlap to form a first overlapping region, and a third battery cell, wherein the third battery cell partially overlaps with the first battery cell in a second direction to form a second overlapping region. In the first overlapping region, the local height of the second battery cell is greater than the local height of the first battery cell, and in the second overlapping region, the local height of the third battery cell is greater than the local height of the first battery cell.

2. The battery assembly as claimed in claim 1, characterized in that, The local height of the third battery cell within the second overlapping region is equal to the local height of the second battery cell within the first overlapping region.

3. The battery assembly as described in claim 1, characterized in that, The battery assembly further includes a fourth battery cell, which partially overlaps with the third battery cell along the first direction to form a third overlapping region. Within the third overlapping region, the local height of the fourth battery cell is greater than the local height of the third battery cell.

4. The battery assembly as described in claim 3, characterized in that, The fourth battery cell overlaps with the second battery cell in the second direction to form a fourth overlapping region, wherein the local height of the fourth battery cell is greater than the local height of the second battery cell in the fourth overlapping region.

5. The battery assembly as claimed in claim 3, characterized in that, The fourth battery cell overlaps with the second battery cell in the second direction to form a fourth overlapping region. In the fourth overlapping region, the local height of the fourth battery cell is less than the local height of the second battery cell.

6. The battery assembly as claimed in claim 3, characterized in that, The first and second battery cells partially overlap along the first direction to form a first battery string, and the third and fourth battery cells partially overlap along the first direction to form a second battery string.

7. The battery assembly as claimed in claim 6, characterized in that, The first battery string and the second battery string are partially overlapped along the second direction.

8. The battery assembly as claimed in claim 3, characterized in that, The first battery cell, the second battery cell, the third battery cell, and the fourth battery cell enclose a closed area.

9. The battery assembly as claimed in claim 8, characterized in that, The projection of the enclosed region in a third direction is a triangle or a rhombus.

10. The battery assembly as claimed in claim 4, characterized in that, The first battery cell has a first height in the first overlapping region, and the second battery cell has a second height in the first overlapping region. The difference between the first height and the second height is in the range of 100 to 200 micrometers.

11. The battery assembly as claimed in claim 10, characterized in that, The first battery cell has the first height in the second overlapping region, and a portion of the third battery cell has a third height in the second overlapping region, wherein the difference between the third height and the first height is in the range of 100 to 200 micrometers.

12. The battery assembly as claimed in claim 11, characterized in that, The third height is equal to the second height.

13. The battery assembly as claimed in claim 10, characterized in that, The third battery cell has a fourth height in a portion of the third overlapping region, and the fourth battery cell has a fifth height in the third overlapping region. The difference between the fifth height and the fourth height is in the range of 100 to 200 micrometers.

14. The battery assembly as claimed in claim 13, characterized in that, The difference between the fifth height and the first height is in the range of 200 to 400 micrometers.

15. The battery assembly as claimed in claim 10, characterized in that, The second battery cell has a sixth height in the fourth overlapping region, and the fourth battery cell has a seventh height in the fourth overlapping region, the difference between the sixth height and the seventh height being 100 to 200 micrometers.

16. The battery assembly as claimed in claim 15, characterized in that, When the seventh height is greater than the sixth height, the difference between the seventh height and the first height is in the range of 200 to 400 micrometers.

17. The battery assembly as claimed in claim 15, characterized in that, When the seventh height is less than the sixth height, the seventh height and the first height are equal.

18. The battery assembly as claimed in claim 3, characterized in that, Each of the first, second, third, and fourth battery cells includes a chamfered edge and a cut edge without chamfering, the chamfered edge and the cut edge being opposite each other.

19. The battery assembly as claimed in claim 18, characterized in that, Along the first direction, the cut edge of the first battery cell and the chamfered edge of the second battery cell overlap.

20. The battery assembly as claimed in claim 18, characterized in that, Along the first direction, the chamfered edges of the first battery cell and the chamfered edges of the second battery cell overlap.

21. The battery assembly as claimed in claim 18, characterized in that, Along the first direction, the cut edge of the third battery cell and the chamfered edge of the fourth battery cell overlap.

22. The battery assembly as claimed in claim 18, characterized in that, Along the first direction, the chamfered edges of the third battery cell and the fourth battery cell overlap.

23. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1-22.

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