Battery assembly and photovoltaic system

Abstract

The utility model is suitable for photovoltaic technical field provides a kind of battery component and photovoltaic system, including first cell piece and second cell piece sequentially arranged along first direction;Insulating strip and busbar are sequentially stacked on the second cell piece in third direction;The utility model can set up busbar on second cell piece, can ensure that first solder strip can be fully and effectively welded with the position of first cell piece, welding, simultaneously, by the projection of first solder strip on busbar and the projection of corresponding second solder strip on busbar Partial overlap, reduce the overlapping area of heteropolarity solder strip in busbar area, reduce stress concentration area, reduce the risk of cell piece's hidden crack, and in preparation process, the welding position deviation of first solder strip or second solder strip can be allowed, effectively reduce production accuracy requirement and production difficulty, improve yield.

Description

Technical Field

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

[0002] Solar cells, also known as photovoltaic cells, are devices that directly convert light energy into direct current using the photovoltaic effect. The PN junction on the semiconductor in a solar cell can directly convert solar energy into electrical energy through the photovoltaic effect. The most common type is the crystalline silicon solar cell, which includes monocrystalline and polycrystalline silicon solar cells. Solar cells are typically in sheet form.

[0003] In related technologies, multiple solar cells are strung together to form a solar cell string. The solar cell strings are connected by busbars to form a solar cell module. The busbars are installed on the back of the solar cells, and an insulating film is set between the busbars and the solar cells. In the area where the busbars and the insulating film are set, the stacking of opposite polarity solder strips and busbars can easily cause stress concentration. During the lamination process of the photovoltaic module, this can easily lead to solar cell fragments or microcracks. Utility Model Content

[0004] This utility model provides a battery module designed to solve the problem that stress concentration is easily formed in the stacking of opposite polarity solder strips and busbars in the area where the busbars and insulating film are set, which can easily lead to cell fragmentation or microcracks during the lamination process of photovoltaic modules.

[0005] In a first aspect, this utility model is implemented as follows: a battery assembly includes a first battery cell and a second battery cell arranged sequentially along a first direction; an insulating strip and a busbar sequentially stacked on the second battery cell in a third direction; a plurality of first solder strips spaced apart along a second direction on the first battery cell, the plurality of first solder strips extending along the first direction and electrically connected to the busbar respectively; a plurality of second solder strips spaced apart along the second direction on the second battery cell, the plurality of second solder strips extending along the first direction and insulated from the busbar respectively; the plurality of first solder strips and the plurality of second solder strips are arranged in a one-to-one correspondence, and the projection of the first solder strip on the busbar and the projection of the corresponding second solder strip on the busbar partially overlap.

[0006] Optionally, the first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area overlap to form a second overlapping area, and the area of ​​the first overlapping area is less than or equal to the area of ​​the second overlapping area.

[0007] Optionally, the area of ​​the first overlapping region is greater than or equal to 2 / 3 of the area of ​​the second overlapping region.

[0008] Optionally, the first overlapping region and the second overlapping region partially overlap in the first direction.

[0009] Optionally, the first projection area and the second projection area overlap to form a third overlapping area, the area of ​​the third overlapping area being greater than or equal to 1 / 4 of the area of ​​the first projection area.

[0010] Optionally, the first overlapping region and the second overlapping region partially overlap in the second direction.

[0011] Optionally, the first projection area and the second projection area overlap to form a fourth overlapping area, and the area of ​​the fourth overlapping area is greater than or equal to 1 / 3 of the area of ​​the first projection area.

[0012] Optionally, the battery assembly further includes third solder strips, a plurality of which extend from the first battery cell to the second battery cell along the first direction, the third solder strips connecting the first battery cell and the second battery cell.

[0013] Optionally, along the second direction, the distance between the nth first solder strip and the nth third solder strip is a first distance, and the distance between the nth third solder strip and the (n+1)th first solder strip is a second distance. The first distance and the second distance are different, and n is a positive integer.

[0014] Optionally, the first battery cell and the second battery cell partially overlap along the first direction to form a battery string, with the first battery cell located at the end of the battery string.

[0015] Optionally, along the second direction, the distance between the nth second weld strip and the nth third weld strip is the third distance, and the distance between the nth third weld strip and the (n+1)th second weld strip is the fourth distance, where the third distance and the fourth distance are the same, and n is a positive integer.

[0016] Optionally, in the first direction, the width of the busbar is less than or equal to the width of the insulating strip.

[0017] This invention allows the busbar to be positioned on the second battery cell, ensuring that the first solder strip can fully adhere to and weld with the effective welding position of the first battery cell. This avoids insufficient welding between the first solder strip and the first battery cell due to the busbar, which would affect current collection. During assembly, an insulating strip is placed between the second battery cell and the busbar for isolation. The insulating strip does not require holes or arrangement, greatly simplifying the processing and installation process. At the same time, by overlapping the projection of the first solder strip on the busbar with the corresponding projection of the second solder strip on the busbar, the overlapping area of ​​opposite polarity solder strips in the busbar area is reduced, stress concentration areas are reduced, and the risk of microcracks in the battery cell is lowered. Furthermore, the welding position deviation of the first or second solder strip can be allowed during the manufacturing process, effectively reducing the production precision requirements and production difficulty, and improving the yield.

[0018] Secondly, this utility model is implemented as follows: a battery assembly includes a first battery cell and a second battery cell arranged sequentially along a first direction; an insulating strip and a busbar sequentially stacked on the second battery cell in a third direction; a plurality of first solder strips spaced apart along a second direction on the first battery cell, the plurality of first solder strips extending along the first direction and electrically connected to the busbars respectively; a plurality of second solder strips spaced apart along the second direction on the second battery cell, the plurality of second solder strips extending along the first direction and insulated from the busbars respectively; the plurality of first solder strips and the plurality of second solder strips are arranged in a one-to-one correspondence, and the first solder strips and the corresponding second solder strips are spaced apart in the first direction.

[0019] Optionally, the first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area overlap to form a second overlapping area, and the first overlapping area and the second overlapping area are spaced apart by a first distance.

[0020] Optionally, the first distance is greater than or equal to 1 / 4 of the width of the busbar.

[0021] Optionally, the length of the first overlapping region in the first direction is greater than or equal to 1 / 2 of the width of the busbar.

[0022] Optionally, the first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area do not overlap, and the second projection area and the first overlapping area are spaced apart by a second distance.

[0023] Optionally, the second distance is greater than or equal to 1 / 4 of the width of the busbar.

[0024] This invention allows the busbar to be positioned on the second battery cell, ensuring that the first solder strip can fully adhere to and weld with the effective welding position of the first battery cell. This avoids insufficient welding between the first solder strip and the first battery cell due to the busbar, which would affect current collection. During assembly, an insulating strip is placed between the second battery cell and the busbar for isolation. The insulating strip does not require holes or arrangement, greatly simplifying the processing and installation process. At the same time, by spacing the first solder strip and the corresponding second solder strip in the first direction, the overlap of opposite polarity solder strips in the busbar area is avoided, reducing the local stacking height, eliminating stress concentration areas, and reducing the risk of microcracks in the battery cell. Furthermore, the invention allows for deviations in the welding position of the first or second solder strip during the manufacturing process, effectively reducing production precision requirements and manufacturing difficulty, and improving yield.

[0025] Thirdly, a photovoltaic system includes the battery module described in the first or second aspect. The technical effects of this invention are the same as those of the battery module described in the first or second aspect, and will not be repeated here. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of the first type of battery assembly provided in this utility model application;

[0027] Figure 2 yes Figure 1 A magnified structural diagram at point A;

[0028] Figure 3 This is a cross-sectional schematic diagram of the first type of battery assembly provided in this utility model application;

[0029] Figure 4 This is a schematic diagram of the structure of the second type of battery assembly provided in this utility model application;

[0030] Figure 5 yes Figure 4 A magnified structural diagram at point B;

[0031] Figure 6This is a cross-sectional schematic diagram of the second type of battery assembly provided in this utility model application;

[0032] Figure 7 This is a schematic diagram of the structure of the third type of battery assembly provided in this utility model application;

[0033] Figure 8 yes Figure 7 A magnified structural diagram at point C;

[0034] Figure 9 This is a cross-sectional schematic diagram of the third type of battery assembly provided in this utility model application;

[0035] Figure 10 This is a schematic diagram of the structure of the fourth type of battery assembly provided in this utility model application;

[0036] Figure 11 yes Figure 10 A magnified structural diagram at point D;

[0037] Figure 12 This is a cross-sectional schematic diagram of the fourth type of battery assembly provided in this utility model application.

[0038] Explanation of reference numerals in the attached figures:

[0039] 100. Battery module; 101. First battery cell; 102. Second battery cell; 103. Busbar; 104. First solder strip; 105. Insulating strip; 106. Second solder strip; 107. Third solder strip; 200. Battery string; 300. First overlapping area; 400. Second overlapping area; 500. Third overlapping area; 600. Fourth overlapping area. Detailed Implementation

[0040] 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. 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 utility model, and should not be construed as limiting this utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this utility model and are not intended to limit this utility model.

[0041] In the description of this utility model, 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. 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.

[0042] 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.

[0043] 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.

[0044] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0045] 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, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0046] like Figure 1 , Figure 2 and Figure 3 As shown, in some embodiments, a battery assembly 100 includes a first battery cell 101 and a second battery cell 102 arranged sequentially along a first direction. The first battery cell 101 and the second battery cell 102 arranged sequentially along the first direction can be connected in series to form a battery string 200. Exemplarily, the first battery cell 101 and the second battery cell 102 partially overlap along the first direction to form the battery string 200, thus eliminating gaps between the battery cells. The solder ribbon can be hidden on the back of the battery cell, resulting in a better overall aesthetic appearance of the battery assembly 100 when viewed from the light-receiving surface (or "front"). The first battery cell 101 is located at the end of the battery string 200; that is, in the first direction, the first battery cell 101 is either the first positive battery cell or the last positive battery cell in the battery string 200. It is understood that the battery string 200 may include two battery cells connected in series, three battery cells connected in series, or a greater number of battery cells. The specific number of battery cells to be connected in series can be determined according to the actual usage, and this invention does not limit this. Furthermore, the battery assembly 100 may include two battery strings 200, three battery strings 200, or more battery strings 200. The multiple battery strings 200 can be connected in series or in parallel. The specific number of battery strings 200 and the connection method can be determined according to the actual use. This utility model does not impose any restrictions on this.

[0047] Busbar 103 is used for current collection between battery strings 200. Busbar 103 is electrically connected to the first solder strip 104 disposed on the first battery cell 101. Busbar 103 is disposed on the second battery cell 102, and an insulating strip 105 is disposed between busbar 103 and the second battery cell 102. The insulating strip 105 is used to insulate the busbar 103 and the solder strip on the second battery cell 102 to avoid short circuits or leakage current caused by solder strip contact. Compared to when busbar 103 is disposed in the middle of the back side of the first battery cell 101, the first solder strip 104 cannot be soldered to the first battery cell 101 in the position covered by busbar 103, resulting in insufficient welding between the first solder strip 104 and the first battery cell 101 and poor current collection. The busbar 103 of this invention is disposed on the back surface of the second battery cell 102. The first solder ribbon 104 can fully fit and weld with the effective welding position of the first battery cell 101, avoiding insufficient welding between the first solder ribbon 104 and the first battery cell 101 due to the installation of the busbar 103, which would affect the current collection. At the same time, after the first solder ribbon 104 is welded to the first battery cell 101, it can be directly connected to the busbar 103 without the need to open the insulating strip 105. During assembly, the insulating strip 105 only needs to be placed on the second battery cell 102 as a whole, which effectively reduces the production precision requirements and production difficulty, and can avoid short circuits caused by positional displacement when the insulating strip 105 is opened, thereby increasing the product yield.

[0048] Furthermore, since the first solder strip 104 needs to extend to the second battery cell 102 and be electrically connected to the busbar 103, and the busbar 103 and the insulating strip 105 are disposed at the edge of the second battery cell 102 near the first battery cell 101, the first solder strip 104 can achieve electrical connection with the busbar 103 at the edge of the second battery cell 102 with a relatively short extension length, avoiding short circuit caused by the first solder strip 104 extending too long on the second battery cell 102 and contacting the opposite polarity region on the second battery cell 102.

[0049] It is understood that the grid lines on the solar cells described above are not shown in the attached diagram. The grid lines on the solar cells can be arranged according to actual conditions; for example, it can be a solar cell with main grids or a solar cell without main grids. The type of solar cell can be a back contact cell, that is, all electrodes (positive and negative electrodes) 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.

[0050] In this embodiment of the invention, the second direction intersects the first direction. The third direction intersects the first direction, and the third direction intersects the second direction. Specifically, the second direction may be perpendicular to the first direction. The third direction may be perpendicular to the first direction, and the third direction may be perpendicular to the second direction. For example, the first direction may be the width direction of the battery cell, the second direction may be the length direction of the battery cell, and the third direction may be the thickness direction of the battery cell.

[0051] In some embodiments, a plurality of first solder ribbons 104 are spaced apart along a second direction on the first battery cell 101, the plurality of first solder ribbons 104 extend along a first direction, and the plurality of first solder ribbons 104 are electrically connected to the busbar 103 respectively; it is understood that the plurality of first solder ribbons 104 are disposed in the same polarity region, and a plurality of second solder ribbons 106 are spaced apart along a second direction on the second battery cell 102, the plurality of second solder ribbons 106 extend along the first direction, and the plurality of second solder ribbons 106 are insulated from the busbar 103 respectively; it is understood that the plurality of second solder ribbons 106 are disposed in the same polarity region, the plurality of first solder ribbons 104 and the plurality of second solder ribbons 106 are disposed in a one-to-one correspondence, and the polarity of the polarity region disposed of the plurality of first solder ribbons 104 is opposite to that of the polarity region disposed of the plurality of second solder ribbons 106, and the projection of the first solder ribbon 104 on the busbar 103 and the projection of the corresponding second solder ribbon 106 on the busbar 103 partially overlap. In other words, the projection of the first solder strip 104 on the busbar 103 and the projection of the corresponding second solder strip 106 on the busbar 103 partially overlap. That is, in the third direction, a part of the projection of the first solder strip 104 on the busbar 103 is located within the projection of the second solder strip 106 on the busbar 103, and another part of the projection of the first solder strip 104 on the busbar 103 is located outside the projection of the second solder strip 106 on the busbar 103.

[0052] Compared to the complete overlap of the projections of the first solder strip 104 and the second solder strip 106 on the busbar 103, the partial overlap of the projections of the first solder strip 104 and the corresponding second solder strip 106 on the busbar 103 reduces the overlapping area of ​​the opposite polarity solder strips in the busbar region, reduces stress concentration areas, and lowers the risk of microcracks in the solar cells. Compared to the complete misalignment of the projections of the first solder strip 104 and the second solder strip 106 on the busbar 103, the partial overlap increases the thickness of the weld layer in the overlapping area, forming a connection point with stronger local rigidity and higher load-bearing capacity. This disperses the stress generated by external loads (such as wind pressure and snow load), reducing the risk of microcracks. The partial overlap also increases the contact area between the solder strip and the busbar, making the current path more direct, reducing contact resistance, and decreasing current transmission loss.

[0053] In some embodiments, the first solder ribbon 104 has a first projection area on the second solar cell 102, the second solder ribbon 106 has a second projection area on the second solar cell 102, and the busbar 103 has a third projection area on the second solar cell 102. The first and third projection areas overlap to form a first overlapping area 300, and the second and third projection areas overlap to form a second overlapping area 400. The area of ​​the second overlapping area 400 is greater than or equal to the area of ​​the first overlapping area 300. As described above, this means that the projected area of ​​the second solder ribbon 106 in the third projection area is greater than or equal to the area of ​​the first solder ribbon 104 in the third projection area. This allows the first solder ribbon 104 to reduce heat generation by increasing its contact area with the busbar 103, providing flexible buffering, adapting to local deformation, and improving its resistance to bending fatigue. Furthermore, it ensures that the second solder ribbon 106 efficiently collects charge carriers at the edge of the second solar cell 102, quickly discharging edge current and preventing localized temperature rise.

[0054] In some embodiments, the area of ​​the first overlapping region 300 is greater than or equal to 2 / 3 of the area of ​​the second overlapping region 400. Within this range, the first solder strip 104 and the busbar 103 have a larger contact area, limiting heat generation and preventing temperature rise caused by poor heat dissipation in the first overlapping region 300.

[0055] like Figure 2 As shown, in some embodiments, the first overlapping region and the second overlapping region partially overlap in the first direction. That is, the first solder strip 104 and the second solder strip 106 can partially overlap in the extending direction. Furthermore, the first overlapping region 300 and the second overlapping region 400 partially overlap in the first direction, forming a connection point with stronger local rigidity in the area where the busbar 103 and the insulating strip 105 are set. This has better load-bearing capacity, disperses stress and external mechanical loads (such as wind pressure and snow load), reduces the risk of microcracks in the battery cell, and in outdoor environments, the solder joints have high reliability due to redundant support.

[0056] In some embodiments, the first projection area and the second projection area overlap to form a third overlapping area 500, and the area of ​​the third overlapping area 500 is greater than or equal to 1 / 4 of the area of ​​the first projection area. The area of ​​the third overlapping area 500 is set within the above-mentioned range, that is, the first solder strip 104 and the second solder strip 106 have a sufficiently large overlap area to ensure sufficient support in the area where the busbar 103 and the insulating strip 105 are set, thereby improving the bending strength of the component and the high tolerance of the solder strip welding position, thus improving the component yield.

[0057] like Figure 4 , Figure 5 and Figure 6As shown, in some embodiments, the first overlapping region and the second overlapping region partially overlap in the second direction. That is, the first solder strip 104 and the second solder strip 106 can partially overlap in the width direction, forming a multi-level stepped fixing structure in the area where the busbar 103 and the insulating strip 105 are set. This disperses stress and external mechanical loads (such as wind pressure and snow load), avoids stress concentration, reduces the risk of microcracks in the solar cell, enhances the structural coupling between the solar cell and the solder strip, improves bending strength, allows for positional deviation of the solder strip in the width direction, and reduces the dependence on absolute alignment of the solder strip.

[0058] In some embodiments, the first projection area and the second projection area overlap to form a fourth overlapping area 600, and the area of ​​the fourth overlapping area 600 is greater than or equal to 1 / 3 of the area of ​​the first projection area. The area of ​​the fourth overlapping area 600 is set within the aforementioned range, meaning that the first solder strip 104 and the second solder strip 106 have a sufficiently large overlap area to ensure sufficient support is formed in the area where the busbar 103 and the insulating strip 105 are located, improving the bending strength of the component, and the solder strip welding position has high tolerance, thus improving the component yield.

[0059] In some embodiments, the battery assembly 100 further includes third solder ribbons 107. Along a first direction, a plurality of third solder ribbons 107 extend from the first battery cell 101 to the second battery cell 102, connecting the first battery cell 101 and the second battery cell 102. An insulating strip 105 isolates the third solder ribbons 107 from the busbar 103. Specifically, a portion of the third solder ribbon 107 is disposed on the first battery cell 101, and another portion of the third solder ribbon 107 is disposed on the second battery cell 102. Exemplarily, the third solder ribbons 107 can be used to achieve a series connection between the first battery cell 101 and the second battery cell 102. Understandably, the portions of the first solder ribbon 104 and the third solder ribbon 107 disposed on the first battery cell 101 do not overlap, and the remaining portions of the second solder ribbon 106 and the third solder ribbon 107 disposed on the second battery cell 102 do not overlap. Along the length of the busbar 103, portions of the first solder ribbon 104 and the third solder ribbon 107 disposed on the first battery cell 101 are spaced apart, and the remaining portions of the second solder ribbon 106 and the third solder ribbon 107 disposed on the second battery cell 102 are spaced apart. In this embodiment of the present invention, there are multiple third solder ribbons 107, with at least one first solder ribbon 104 and one second solder ribbon 106 disposed between two adjacent third solder ribbons 107 to achieve a uniform current distribution on the battery cell.

[0060] In some embodiments, along the second direction, the distance between the nth first solder strip 104 and the nth third solder strip 107 is a first distance, and the distance between the nth third solder strip 107 and the (n+1)th first solder strip 104 is a second distance. The first distance and the second distance are different, and n is a positive integer. Compared to a uniformly spaced solder strip distribution, with the same cell size and the same number of solder strips, the distance between two adjacent first solder strips 104 and the distance between two adjacent third solder strips 107 can be relatively close, thereby shortening the carrier transport path and improving the cell efficiency.

[0061] In some embodiments, along the second direction, the distance between the nth second solder strip 106 and the nth third solder strip 107 is a third distance, and the distance between the nth third solder strip 107 and the (n+1)th second solder strip 106 is a fourth distance. The third distance and the fourth distance are the same, and n is a positive integer. Thus, the multiple second solder strips 106 and multiple third solder strips 107 are evenly distributed on the second solar cell 102. This uniform solder strip layout helps reduce the internal resistance of the solar cell. The equidistant solder strip layout helps optimize resistance characteristics and improve current transmission efficiency.

[0062] In some embodiments, in the first direction, the width of the busbar 103 is less than or equal to the width of the insulating strip 105. This ensures complete isolation between the insulating strip 105 and the solder ribbon. If the width of the insulating strip 105 is too narrow, the busbar 103 will be exposed, posing a risk of short circuit due to contact between the busbar 103 and the opposite electrode area.

[0063] like Figure 7 , Figure 8 and Figure 9 As shown, in some embodiments, a battery assembly includes a first battery cell 101 and a second battery cell 102 arranged sequentially along a first direction. The first battery cell 101 and the second battery cell 102 arranged sequentially along the first direction can be connected in series to form a battery string 200. For example, the first battery cell 101 and the second battery cell 102 partially overlap along the first direction to form the battery string 200. In this way, there are no gaps between the battery cells, and the solder ribbon can be hidden on the back of the battery cell. When viewed from the light-receiving surface (or "front") of the battery cell, the overall aesthetics of the battery assembly 100 are better.

[0064] An insulating strip 105 and a busbar 103 are sequentially stacked on the second battery 102. The busbar 103 is used for current convergence between the battery strings 200. The busbar 103 is electrically connected to the first solder strip 104 disposed on the first battery cell 101. The busbar 103 is disposed on the second battery cell 102, and an insulating strip 105 is disposed between the busbar 103 and the solder strip located on the second battery cell 102. The insulating strip 105 is used to insulate the busbar 103 and the solder strip located on the second battery cell 102 to avoid short circuits or leakage current caused by solder strip contact.

[0065] A plurality of first solder ribbons 104 are spaced apart along a second direction on the first battery cell 101, extending along a first direction, and are electrically connected to the busbar 103 respectively. A plurality of second solder ribbons 106 are spaced apart along a second direction on the second battery cell 102, extending along the first direction, and are insulated from the busbar 103 respectively. It is understood that the plurality of first solder ribbons 104 are located in the same polarity region, and the plurality of second solder ribbons 106 are spaced apart along a second direction on the second battery cell 102, extending along the first direction, and are insulated from the busbar 103 respectively. It is also understood that the plurality of second solder ribbons 106 are located in the same polarity region, and the plurality of first solder ribbons 104 and the plurality of second solder ribbons 106 are arranged in a one-to-one correspondence, and the polarity of the polarity regions of the plurality of first solder ribbons 104 and the polarity regions of the plurality of second solder ribbons 106 are opposite.

[0066] Multiple first solder strips 104 and multiple second solder strips 106 are arranged in a one-to-one correspondence, with the first solder strips 104 and their corresponding second solder strips 106 spaced apart in a first direction. That is, the projections of the first solder strips 104 and the second solder strips 106 on the second solar cell 102 do not overlap. Therefore, there is no stress concentration area in the area where the busbar 103 is set due to the overlap of opposite polarity solder strips in the thickness direction of the solar cell, reducing the risk of microcracks in the solar cell when the solder strips are laminated on it.

[0067] In some embodiments, the first solder ribbon 104 has a first projection area on the second cell 102, the second solder ribbon 106 has a second projection area on the second cell 102, and the busbar 103 has a third projection area on the second cell 102. The first and third projection areas overlap to form a first overlapping area, and the second and third projection areas overlap to form a second overlapping area. The first and second overlapping areas are spaced apart by a first distance. That is, the first solder ribbon 104 and the busbar 103 have overlapping areas, and the second solder ribbon 106 and the busbar 103 also have overlapping areas. Since the busbar 103 is generally located in the edge region of the second cell 102, this helps the second solder ribbon collect as many charge carriers as possible from the edge of the second cell, reducing the efficiency loss of the battery module.

[0068] In some embodiments, the first distance is greater than or equal to 1 / 4 of the width of the busbar 103. Exemplarily, the first distance can be 1 / 4, 1 / 3, or 1 / 2 of the width of the busbar 103. Within this range, the first distance allows the first and second solder strips to be as far apart as possible in the first direction, avoiding stress concentration in the busbar area and minimizing the risk of microcracks in the solar cell.

[0069] In some embodiments, the length of the first overlapping region in the first direction is greater than or equal to half the width of the busbar 103. For example, the length of the first overlapping region can be half or two-thirds of the width of the busbar 103. That is, the first solder strip 104 and the busbar 103 have a large overlapping area, and the first solder strip 104 and the busbar 103 are electrically connected. This ensures the stability of the connection between the busbar and the first solder strip, achieving efficient current collection.

[0070] like Figure 10 , Figure 11 and Figure 12 As shown, in some embodiments, the first solder ribbon 104 has a first projection area on the second solar cell 102, the second solder ribbon 106 has a second projection area on the second solar cell 102, and the busbar 103 has a third projection area on the second solar cell 102. The first and third projection areas overlap to form a first overlapping area, while the second and third projection areas do not overlap. The second projection area and the first overlapping area are spaced apart by a second distance. That is, the first solder ribbon 104 and the busbar 103 have overlapping areas, while the second solder ribbon 106 and the busbar 103 do not. This effectively reduces the local stacking height in the busbar placement area, as only the first solder ribbon and the busbar are stacked, thereby reducing the risk of microcracks in the solar cell.

[0071] In some embodiments, the second distance is greater than or equal to 1 / 4 of the width of the busbar 103. For example, the second distance can be 1 / 4 or 2 / 3 of the width of the busbar 103. Since the second solder ribbon 106 and the busbar 103 do not overlap, there is less insulation between them. With the second distance within the aforementioned range, mutual insulation between opposite polarity solder ribbons can be ensured, avoiding the risk of partial short circuits in the battery assembly.

[0072] In some embodiments, 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.

[0073] 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 the described 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.

[0074] The above description is only 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, characterized in that, The device includes a first battery cell and a second battery cell arranged sequentially along a first direction; an insulating strip and a busbar sequentially stacked on the second battery cell in a third direction; a plurality of first solder strips spaced apart along a second direction on the first battery cell, the plurality of first solder strips extending along the first direction and electrically connected to the busbar respectively; a plurality of second solder strips spaced apart along the second direction on the second battery cell, the plurality of second solder strips extending along the first direction and insulated from the busbar respectively; the plurality of first solder strips and the plurality of second solder strips are arranged in a one-to-one correspondence, and the projection of the first solder strip on the busbar and the projection of the corresponding second solder strip on the busbar partially overlap.

2. The battery assembly as claimed in claim 1, characterized in that, The first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area overlap to form a second overlapping area, and the area of ​​the first overlapping area is less than or equal to the area of ​​the second overlapping area.

3. The battery assembly as described in claim 2, characterized in that, The area of ​​the first overlapping region is greater than or equal to 2 / 3 of the area of ​​the second overlapping region.

4. The battery assembly as described in claim 2, characterized in that, The first overlapping region and the second overlapping region partially overlap in the first direction.

5. The battery assembly as claimed in claim 4, characterized in that, The first projection area and the second projection area overlap to form a third overlapping area, and the area of ​​the third overlapping area is greater than or equal to 1 / 4 of the area of ​​the first overlapping area.

6. The battery assembly as claimed in claim 2, characterized in that, The first overlapping region and the second overlapping region partially overlap in the second direction.

7. The battery assembly as claimed in claim 6, characterized in that, The first projection area and the second projection area overlap to form a fourth overlapping area, and the area of ​​the fourth overlapping area is greater than or equal to 1 / 3 of the area of ​​the first overlapping area.

8. The battery assembly as claimed in claim 1, characterized in that, The battery assembly also includes third solder strips, and along the first direction, a plurality of the third solder strips extend from the first battery cell to the second battery cell, the third solder strips connecting the first battery cell and the second battery cell.

9. The battery assembly as claimed in claim 8, characterized in that, Along the second direction, the distance between the nth first solder strip and the nth third solder strip is the first distance, and the distance between the nth third solder strip and the (n+1)th first solder strip is the second distance. The first distance and the second distance are different, and n is a positive integer.

10. The battery assembly as claimed in claim 1, characterized in that, The first battery cell and the second battery cell partially overlap along the first direction to form a battery string, with the first battery cell located at the end of the battery string.

11. The battery assembly as claimed in claim 8, characterized in that, Along the second direction, the distance between the nth second weld strip and the nth third weld strip is the third distance, and the distance between the nth third weld strip and the (n+1)th second weld strip is the fourth distance. The third distance and the fourth distance are the same, and n is a positive integer.

12. The battery assembly as claimed in claim 1, characterized in that, In the first direction, the width of the busbar is less than or equal to the width of the insulating strip.

13. A battery assembly, characterized in that, The device includes a first battery cell and a second battery cell arranged sequentially along a first direction; an insulating strip and a busbar sequentially stacked on the second battery cell in a third direction; a plurality of first solder strips spaced apart along a second direction on the first battery cell, the plurality of first solder strips extending along the first direction and electrically connected to the busbars respectively; a plurality of second solder strips spaced apart along the second direction on the second battery cell, the plurality of second solder strips extending along the first direction and insulated from the busbars respectively; the plurality of first solder strips and the plurality of second solder strips are arranged in a one-to-one correspondence, and the first solder strips and their corresponding second solder strips are spaced apart in the first direction.

14. The battery assembly as claimed in claim 13, characterized in that, The first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area overlap to form a second overlapping area, and the first overlapping area and the second overlapping area are spaced apart by a first distance.

15. The battery assembly as claimed in claim 14, characterized in that, The first distance is greater than or equal to 1 / 4 of the width of the busbar.

16. The battery assembly as claimed in claim 14, characterized in that, The length of the first overlapping region in the first direction is greater than or equal to 1 / 2 of the width of the busbar.

17. The battery assembly as claimed in claim 13, characterized in that, The first solder strip has a first projection area on the second battery cell, the second solder strip has a second projection area on the second battery cell, the busbar has a third projection area on the second battery cell, the first projection area and the third projection area overlap to form a first overlapping area, the second projection area and the third projection area do not overlap, and the second projection area and the first overlapping area are spaced apart by a second distance.

18. The battery assembly as claimed in claim 17, characterized in that, The second distance is greater than or equal to 1 / 4 of the width of the busbar.

19. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1-12 or 13-18.

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