A battery assembly and photovoltaic system

Abstract

This utility model relates to the field of photovoltaic technology, providing a battery module and a photovoltaic system. The battery module includes: a plurality of battery strings, each battery string including a plurality of battery cells, each battery cell including a first battery cell located at one end of the battery string and a second battery cell adjacent to the first battery cell. The back of the first battery cell is provided with a plurality of first solder strips and a plurality of third solder strips, and the back of the second battery cell is provided with a plurality of second solder strips and a plurality of fourth solder strips; a busbar is provided on the back of the second battery cell, the first solder strips extending toward the second battery cell and connecting to the busbar; the second battery cell includes a first edge near the first battery cell, and the second solder strips include a first end; the distance from the first end to the first edge is d1, and the distance from the busbar to the first edge is d2, where 0.2≦d1 / d2≤0.7. The battery module of this utility model can reduce the risk of microcracks and cell cracks in the battery cells during the lamination process, and improve the production yield of the battery module.

Description

Technical Field

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

[0002] Solar cells, also known as photovoltaic cells, are devices that directly convert light energy into direct current using the photovoltaic effect. In related technologies, multiple solar cells are connected in series and then laminated and encapsulated to form a solar module. The resulting solar module typically includes a back glass, a first encapsulating film, a cell string, a second encapsulating film, and a front glass, which are stacked sequentially.

[0003] In related technologies, edge busbars are typically placed in the edge area of ​​battery modules, while center busbars are typically placed in the middle area. Both require a certain amount of space to be reserved on the module for placement. This reduces the effective light-receiving area of ​​the module, affecting its conversion efficiency and aesthetics.

[0004] In related technologies, to address the aforementioned issues, busbars can be placed on the back of the cells in a battery string. For example, the busbar can be placed on a cell adjacent to the end cell of the battery string, and then the solder strip on the end cell can be welded to the busbar to achieve concealment of the busbar and convergence output. However, since the distance between the busbar and the cell edge is usually not controlled, and the distance between the solder strip and the cell edge is not always controlled, stress concentration can easily occur during lamination, leading to microcracks and cell breakage, posing a significant risk of fragmentation and thus affecting the yield of battery module production. Utility Model Content

[0005] This utility model provides a battery module that aims to solve the problem that existing battery modules are prone to stress concentration, which can lead to microcracks and cracks in the battery cells, resulting in a high risk of fragmentation and thus affecting the production yield of the battery module.

[0006] This invention is implemented by providing a battery assembly, comprising:

[0007] A plurality of battery strings, each battery string comprising a plurality of battery cells connected in series along a first direction, each battery cell comprising a first battery cell located at one end of the battery string and a second battery cell adjacent to the first battery cell. The back of each first battery cell has a plurality of first solder strips and a plurality of third solder strips alternately arranged along a second direction. The back of each second battery cell has a plurality of second solder strips and a plurality of fourth solder strips alternately arranged along the second direction. Each second solder strip corresponds one-to-one with a first solder strip, and each third solder strip corresponds one-to-one with a fourth solder strip and is electrically connected to it. The second direction intersects the first direction.

[0008] A busbar is disposed on the back of the second battery cell, the busbar extends along the second direction, the first solder strip extends toward the second battery cell and connects to the busbar, and the second solder strip and the fourth solder strip are spaced apart from the busbar;

[0009] The second battery cell includes a first edge and a second edge disposed opposite to each other along the first direction, the first edge being disposed closer to the first battery cell than the second edge, and the second solder strip including a first end extending relative to the busbar toward the first battery cell; wherein the distance from the first end to the first edge is d1, the distance from the busbar to the first edge is d2, and 0.2≦d1 / d2≤0.7.

[0010] Preferably, 0.5≦d1 / d2≤0.6.

[0011] Preferably, d1 is 1.5mm to 3.5mm and d2 is 3mm to 15mm.

[0012] Preferably, the battery assembly further includes:

[0013] An insulating strip is located between the busbar and the second battery cell.

[0014] Preferably, the first solder strip comprises:

[0015] The main body portion located on the first battery cell;

[0016] A bent portion connected to the main body and bent away from the direction of the second weld strip; and

[0017] A connecting part connected to the bending portion, the connecting part being connected to the busbar.

[0018] Preferably, the connecting portion is connected to the surface of the busbar opposite to the second battery cell, and the overlap length between the connecting portion and the busbar is greater than half the length of the busbar in the first direction.

[0019] Preferably, the length by which the connecting portion overlaps with the busbar is less than the length of the busbar in the first direction.

[0020] Preferably, the second battery cell includes a third edge and a fourth edge disposed opposite to each other along the second direction, wherein the third edge is disposed closer to the end of the busbar than the fourth edge, and the distance from the end of the busbar to the third edge is d3, wherein d3 is 2mm to 12mm.

[0021] Preferably, the second battery cell is provided with a plurality of pads for connecting the second solder strip, and the pad closest to the first edge is located below the busbar.

[0022] Preferably, the ratio of the width of the busbar to the thickness of the busbar is 15 to 55.

[0023] Preferably, the battery assembly includes at least one series battery string group, the series battery string group including two battery strings arranged along the second direction, wherein in the same series battery string group, the same bus bar extends from the second battery cell in one battery string to the second battery cell in the other battery string, so as to connect the two battery strings in the series battery string group in series.

[0024] Preferably, the battery assembly includes at least one parallel battery string group, the parallel battery string group including a first battery string and a second battery string arranged along the first direction;

[0025] In the parallel battery string group, the first battery cell includes the battery cell located in the first battery string that is closest to the second battery string, the second battery string includes a third battery cell that is the battery cell in the second battery string that is closest to the first battery string, the first solder strip connects the first battery cell and the third battery cell, and the first battery string and the second battery string are connected in parallel through the first solder strip.

[0026] This utility model also provides a photovoltaic system, including the above-mentioned battery components.

[0027] The battery module provided by this utility model hides the busbar by placing it on the back of the second cell in the battery string, thereby increasing the unit light-receiving area of ​​the battery module, improving the module's conversion efficiency, and enhancing the overall aesthetics of the battery module. Simultaneously, by controlling the ratio of the distance from the first end of the second solder strip to the first edge of the second cell to the distance from the busbar to the first edge of the second cell to be between 0.2 and 0.7, a more reasonable relationship between the distances from the busbar to the first edge of the second cell and the distance from the end of the second solder strip to the first edge of the second cell is achieved. This reduces the edge stress of the second cell during the battery module lamination process, effectively preventing stress concentration at the edge of the second cell during lamination. Therefore, it reduces the risk of microcracks and cell breakage during lamination, thereby improving the battery module's production yield. Attached Figure Description

[0028] Figure 1 A plan view of a battery assembly provided for an embodiment of this utility model;

[0029] Figure 2A schematic diagram of a series battery string of a battery assembly provided in an embodiment of this utility model;

[0030] Figure 3 A schematic diagram of the structure of a parallel battery string group of a battery assembly provided for an embodiment of this utility model;

[0031] Figure 4 This is a schematic diagram of a partial structure of a battery assembly provided in an embodiment of the present invention. Detailed Implementation

[0032] 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 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 the present utility model, and should not be construed as limiting the present utility model. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining the present utility model and are not intended to limit the present utility model.

[0033] In the description of this utility model, it should be understood that the terms "upper", "lower", "back", "front", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0034] 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.

[0035] The following disclosure provides numerous different embodiments or examples for implementing various structures of the present invention. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of the invention. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, examples of various specific processes and materials are provided in this invention; however, those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0036] Please refer to Figures 1-4 The present invention provides a battery assembly 100, comprising:

[0037] A plurality of battery strings 1, each battery string 1 comprising a plurality of battery cells 11 connected in series along a first direction Y. Each battery cell 11 includes a first battery cell 111 located at one end of the battery string 1, and a second battery cell 112 adjacent to the first battery cell 111. The back of the first battery cell 111 is provided with a plurality of first solder strips 21 and a plurality of third solder strips 23 alternately arranged along a second direction X. The back of the second battery cell 112 is provided with a plurality of second solder strips 22 and a plurality of fourth solder strips 24 alternately arranged along a second direction X. The second solder strips 22 correspond one-to-one with the first solder strips 21, and the third solder strips 23 and fourth solder strips 24 correspond one-to-one and are electrically connected. The second direction X intersects the first direction Y.

[0038] The busbar 3 is disposed on the back of the second battery cell 111. The busbar 3 extends along the second direction X. One end of the first solder strip 21 extends toward the second battery cell 112 and is connected to the busbar 3. The second solder strip 22 and the fourth solder strip 24 are spaced apart from the busbar 3.

[0039] The second battery cell 112 includes a first edge 1121 and a second edge 1122 disposed opposite to each other along the first direction Y. The first edge 1121 is disposed closer to the first battery cell 111 than the second edge 1122. The second solder strip 22 includes a first end 221 extending relative to the busbar 3 toward the first battery cell 111. The distance from the first end 221 to the first edge 1121 is d1, the distance from the busbar 3 to the first edge 1121 is d2, and 0.2≦d1 / d2≤0.7.

[0040] In this embodiment of the invention, the battery assembly 100 may include a plurality of battery strings 1 and a busbar 3. Each battery string 1 includes a plurality of battery cells 11 connected in series along a first direction Y. In the battery string 1, each battery cell 11 includes a first battery cell 111 located at one end of the battery string 1 and a second battery cell 112 adjacent to the first battery cell 111. The back of the first battery cell 111 is provided with a first solder strip 21, and the back of the second battery cell 112 is provided with a second solder strip 22. Specifically, the ends of the battery string 1 refer to the two ends of the battery string 1 in the first direction Y; that is, at least one of the battery cells 11 located at the two ends of the battery string 1 is a first battery cell 111. The first solder strip 21 is the end output terminal of the battery string 1, used to connect to the busbar 3. Specifically, the battery cell 11 may be a back-contact solar cell.

[0041] In this embodiment of the invention, the busbar 3 is disposed on the back side of the second battery cell 112. The busbar 3 is connected to the first solder strip 21 and is insulated from the second solder strip 22 and the fourth solder strip 24 to achieve the current output of the battery string 1. The busbar 3 extends along a second direction X, which intersects with a first direction Y. The first direction Y is the stringing direction of the battery cells 11 in each battery string 1. The second direction X is preferably perpendicular to the first direction Y. Specifically, the first direction Y and the second direction X can be the longitudinal direction and the transverse direction of the battery assembly 100, respectively. Of course, in some possible embodiments, the second direction X may not be perpendicular to the first direction Y; this is not a limitation. The busbar 3 can be an end busbar of the battery assembly or a middle busbar of the battery assembly.

[0042] In this embodiment of the invention, the back of the second battery cell 112 is provided with a plurality of second solder strips 22 and a plurality of fourth solder strips 24, which are also arranged alternately with the second solder strips 22 along the second direction X. The second solder strips 22 correspond one-to-one with the first solder strips 21 and are mutually insulated; specifically, the first solder strips 21 are insulated from the second solder strips 22 and the fourth solder strips 24. The third solder strips 23 and the fourth solder strips 24 correspond one-to-one and are electrically connected to connect the first battery cell 111 and the second battery cell 112 in series. The first solder strip 21 is the end output terminal of the battery string 1, used to connect to the busbar 3. The second solder strips 22, the third solder strip 23, and the fourth solder strips 24 all extend along the first direction Y.

[0043] In some embodiments, the third solder strip 23 and the fourth solder strip 24 can be a single continuous solder strip, that is, the third solder strip 23 and the fourth solder strip 24 can be integrally formed. Furthermore, in this invention, the battery cells 11 in the battery string 1 are connected in series using the conventional solder strip connection method in the prior art, which will not be described in detail here.

[0044] In this embodiment of the present invention, the second battery cell 112 includes a first edge 1121 disposed near the first battery cell 111, and the second welding strip 22 includes a first end portion 221 extending relative to the busbar 3 toward the first battery cell 111; wherein, the distance from the first end portion 221 to the first edge 1121 is d1, the distance from the busbar 3 to the first edge 1121 is d2, and 0.2≦d1 / d2≤0.7. Specifically, d1 / d2 can be any value among 0.2, 0.22, 0.25, 0.26, 0.3, 0.33, 0.35, 0.37, 0.4, 0.42, 0.45, 0.49, 0.5, 0.55, 0.56, 0.58, 0.6, 0.62, 0.65, 0.67, 0.69, and 0.7.

[0045] In this embodiment of the invention, the busbar 3 is disposed on the back of the second battery cell 112 of the battery string 1, which can hide the busbar 3, thereby increasing the unit light-receiving area of ​​the battery assembly 100, improving the conversion efficiency of the assembly, and enhancing the overall aesthetics of the battery assembly 100. Simultaneously, controlling the ratio of the distance d1 from the first end 221 of the second solder ribbon 22 to the first edge 1121 of the second battery cell 112 to the distance d2 from the busbar 3 to the first edge 1121 of the second battery cell 112 is between 0.2 and 0.7. This ensures a reasonable ratio between the distance from the busbar 3 to the edge of the second battery cell 112 and the distance from the end of the second solder ribbon 22 to the edge of the second battery cell 112, reducing the risk of microcracks and cracks in the second battery cell 112 during the lamination process, thereby improving… Battery module production yield; specifically, when the distance from the end of the second solder strip 22 to the first edge 1121 of the second cell 112 is fixed, controlling 0.2≦d1 / d2≤0.7 can avoid the distance from the busbar 3 to the first edge 1121 of the second cell 112 being too small, which can reduce the edge stress of the second cell 112 during the battery module lamination process, and effectively avoid stress concentration at the edge of the second cell 112 during the lamination process. Therefore, it can reduce the risk of microcracks and cell cracks in the cell during the lamination process, thereby improving the battery module production yield. Moreover, it also avoids the need to set a longer first solder strip 21 due to an excessively large distance from the busbar 3 to the first edge 1121 of the second cell 112, thus reducing the length design of the first solder strip 21 and reducing production costs.

[0046] In this embodiment, the first battery cell 111 and the second battery cell 112 are partially stacked to form an overlapping area, so that there is no gap between the first battery cell 111 and the second battery cell 112, which is conducive to achieving a completely black design on the front of the component.

[0047] As one embodiment of this utility model, 0.5≦d1 / d2≤0.6.

[0048] In this embodiment, by further controlling 0.5≦d1 / d2≤0.6, and further optimizing the relationship between the distance from the busbar 3 to the first edge 1121 of the second cell 112 and the distance from the end of the second solder strip 22 to the first edge 1121 of the second cell 112, the edge stress of the second cell 112 during the lamination process of the battery module can be further reduced, and the risk of microcracks and cell cracks in the cell during the lamination process can be further reduced, thereby further improving the production yield of the battery module.

[0049] In one embodiment of this utility model, d1 is 1.5mm to 3.5mm and d2 is 3mm to 15mm.

[0050] Where d1 can be any value from 1.5mm to 3.5mm, and d2 can be any value from 3mm to 15mm, as long as 0.2 ≤ d1 / d2 ≤ 0.7 is satisfied. For example, d1 can be 1.5mm, d2 can be 3mm, and d1 / d2 is 0.5; another example is d1 can be 3mm, d2 can be 5mm, and d1 / d2 is 0.6; yet another example is d1 can be 3mm, d2 can be 15mm, and d1 / d2 is 0.2.

[0051] In this embodiment, d1 is controlled to be 1.5mm to 3.5mm and d2 to be 3mm to 15mm, which makes it easy to satisfy 0.2≦d1 / d2≤0.7, and d1 and d2 are respectively within the above range. This can further avoid the ratio of the distance from the end of the second welding strip 22 to the first edge 1121 of the second battery cell 112 to the distance from the busbar 3 to the first edge 1121 of the second battery cell 112 being too large or too small. This can reduce the edge stress of the second battery cell 112 during the battery module lamination process, thereby reducing the risk of microcracks and cell cracks in the battery cell during the lamination process. It can also reduce the length of the first welding strip 21, which can reduce production costs.

[0052] As one embodiment of this utility model, the battery assembly 100 further includes:

[0053] Insulating strip 4 is located between busbar 3 and second battery cell 112.

[0054] In this embodiment, by setting an insulating strip 4, the busbar 3 is insulated from the second solder strip 22 and the fourth solder strip 24 through the insulating strip 4, so that the busbar 3 can form a good insulation isolation with the second solder strip 22 and the fourth solder strip 24 on the second battery cell 112, so as to avoid short circuit and leakage.

[0055] Specifically, in such an embodiment, an insulating strip 4 is disposed above the second solder strip 22 and the fourth solder strip 24, and the insulating strip 4 can be continuously extended along the second direction X. The busbar 3 is disposed on the insulating strip 4 to achieve insulation between the second solder strip 22 and the fourth solder strip 24.

[0056] The insulating strip 4 can be an insulating adhesive, or a non-conductive tape or insulating film. For example, it can be a PET or PI tape with acrylic or silicone, or a PET or PI substrate coated with ethylene vinyl acetate copolymer or hot melt adhesive on one or both sides. Understandably, the insulating strip 4 can contain materials such as ethylene vinyl acetate copolymer, resin materials, polyimide or polypropylene or polyethylene, and may also contain an acrylic adhesive layer.

[0057] The width of the insulating strip 4 (i.e., its length in the first direction Y) is greater than or equal to the width of the busbar 3 (i.e., its length in the first direction Y). In this way, the insulating strip 4 can completely insulate the busbar 3 from the second solder strip 22 and the fourth solder strip 24 on the second battery cell 112.

[0058] Please refer to this again. Figure 4 As an embodiment of this utility model, the first welding strip 21 includes:

[0059] The main body 211 is located on the first battery cell 111;

[0060] The bent portion 212 is connected to the main body 211 and bends away from the second weld strip 22; and

[0061] The connecting part 213 is connected to the bending part 212, and the connecting part 213 is connected to the busbar 3.

[0062] In this embodiment, the first solder strip 21 includes a main body 211, a bent portion 212, and a connecting portion 213. The main body 211 extends along a first direction Y and is welded to the first battery cell 111 through a plurality of solder points. The extension of the main body 211 along the first direction Y at least partially overlaps with the second solder strip 22. In some examples, the main body 211 and the second solder strip 22 may be located on the same straight line in the first direction Y. The connecting portion 213 extends between the second solder strip 22 and the fourth solder strip 24 adjacent to each other on the second battery cell 112, and the connecting portion 213 at least partially overlaps with the busbar 3 for welding to the busbar 3, that is, the portion of the connecting portion 213 extending onto the busbar 3 overlaps with the busbar 3 in the thickness direction. The connecting portion 213 is spaced apart from the main body portion 211 and the second welding strip 22 in the second direction X. The main body portion 211 and the connecting portion 213 are connected by a bending portion 212. In the second direction X, the bending portion 212 bends relative to the main body portion 211 toward the side where the connecting portion 213 is located.

[0063] In this embodiment, the connecting portion 213 of the first solder strip 21 is welded to the busbar 3 to achieve current output. Due to the setting of the bending portion 212, the connecting portion 213 of the first solder strip 21 and the second solder strip 22 do not overlap in the thickness direction. During the lamination process, the connecting portion 213 and the second solder strip 22 are staggered in the extension direction of the busbar 3 and will not stack. During the lamination process, the connecting portion 213 can be pressed down close to the second cell 112, thereby reducing the overall stacking height of the entire assembly, effectively avoiding stress concentration during the lamination process, thereby reducing the risk of microcracks and cell cracks in the cell 11 and improving the yield.

[0064] As an embodiment of the present invention, the connecting part 213 is connected to the surface of the busbar 3 away from the second battery cell 112, and the length of the overlap between the connecting part 213 and the busbar 3 is greater than half the length of the busbar 3 in the first direction Y.

[0065] In this embodiment, the overlap length between the connecting part 213 and the busbar 3 is greater than half the length of the busbar 3 in the first direction Y. This can prevent the welding length between the connecting part 213 of the first welding strip 21 and the busbar 3 from being too small, which would lead to unstable welding and reduce the risk of the first welding strip 21 falling off.

[0066] As an embodiment of the present invention, the length of the overlap between the connecting part 213 and the busbar 3 is less than the length of the busbar 3 in the first direction Y.

[0067] In this embodiment, the length of the overlap between the control connection 213 and the busbar 3 is less than the length of the busbar 3 in the first direction Y, so as to prevent the connection 213 from exceeding the edge of the busbar 3 and to prevent the connection 213 from contacting the solder strip or grid line on the second battery cell 111, thereby reducing the risk of short circuit between the first solder strip 21 and the solder strip or grid line on the second battery cell 112.

[0068] In this embodiment, the length direction of the extension 214 is the same as the thickness direction of the busbar 3. By controlling the length of the extension 214 to be less than half the thickness of the busbar 3, the welding fixation of the connection 213 and the busbar 3 can be further improved, the risk of the first solder strip 21 falling off can be further reduced, and the contact between the busbar 3 and the solder strip or grid line on the second battery cell 112 can be avoided to prevent short circuit.

[0069] Please refer to the reference. Figure 2 As an embodiment of the present invention, the second battery cell 112 includes a third edge 1123 and a fourth edge 1124 disposed opposite to each other along the second direction X. The third edge 1123 is disposed closer to the end of the busbar 3 than the fourth edge 1124. The distance from the end of the busbar 3 to the third edge 1123 is d3, where d3 is 2mm to 12mm.

[0070] In this embodiment, the distance d3 from one end of the busbar 3 to the third edge 1123 of the second battery cell 112 is controlled to be 2mm to 12mm, so that the distance from the end of the busbar 3 to the edge of the second battery cell 20 is controlled within a reasonable range, which can further reduce the risk of microcracks in the second battery cell 20.

[0071] Please refer to the reference. Figure 4 As an embodiment of the present invention, the second battery cell 112 is provided with a plurality of pads 7 for connecting the second solder strip 22, and the pad 7 closest to the first edge 1121 is located below the busbar 3.

[0072] In this embodiment, the pad 7 closest to the first edge 1121 is covered by the busbar 3, so that the pad 7 closest to the first edge 1121 is located below the busbar 3, preventing the pad 7 closest to the first edge 1121 from being located outside the busbar 3. The distance d4 from the pad 7 closest to the first edge 1121 to the first edge 1121 can be 4-6 mm. The distance d4 from the pad 7 to the first edge 1121 can be the distance from the center of the pad 7 to the first edge 1121, or it can be the distance from the edge of the pad 7 to the first edge 1121.

[0073] As one embodiment of this utility model, the ratio of the width of the busbar 3 to the thickness of the busbar 3 is 15 to 55.

[0074] In this embodiment, the width of the busbar 3 is its dimension along the first direction Y, and the length of the busbar 3 is its dimension along the second direction X. The ratio of the width to the thickness of the busbar 3 is controlled to be between 15 and 55, ensuring that this ratio is within a reasonable range. This avoids the need for a thicker encapsulation film due to an excessively thick busbar 3, thus reducing costs and minimizing the risk of microcracks in the battery cells. Furthermore, it prevents the excessive width of the busbar 3 from affecting the bifaciality.

[0075] In some embodiments, the battery assembly 100 may include a plurality of battery strings 1. Specifically, the battery assembly 100 may include twelve battery strings 1, which are arranged in six columns in the second direction X, with each column including two battery strings 1 arranged in the first direction Y. The number of battery cells 11 included in each battery string 1 is not limited; for example, the number of battery cells 11 included in each battery string 1 may be 3 to 20. Figure 1 The diagram only shows that each battery string 1 has 8 battery cells. Specifically, as shown... Figure 1 As shown, the battery assembly 100 is divided into an upper half and a lower half in the first direction Y (as shown in the figure). Figure 1 The center line L is the boundary.

[0076] like Figure 1As shown, the upper half of the battery assembly 100 has six battery strings 1 arranged along the second direction X, and the lower half also has six battery strings 1 arranged along the second direction X. In the battery assembly 100, the busbar 3 may include an edge busbar located at the edge of the battery assembly 100 and an intermediate busbar located in the middle of the battery assembly 100.

[0077] In other words, in Figure 1 In the upper half of the battery assembly 100, if the battery cell 11 closest to the upper edge of the battery string 1 is the first battery cell 111, then the busbar 3 is an end busbar, used to connect two adjacent battery strings 1 in the upper half. In the upper half, if the battery cell 11 closest to the lower edge of the battery string 1 is the first battery cell 111, then the busbar 3 is an intermediate busbar, used to connect the battery string 1 in parallel with the battery string 1 in the lower half. In the upper half, if both battery cells 11 at both ends of the battery string 1 are first battery cells 111, then the busbar 3 closest to the upper edge is an end busbar, and the busbar 3 closest to the lower edge is an intermediate busbar.

[0078] Similarly, such as Figure 1 As shown, in the lower half of the battery assembly 100, if the battery cell 11 closest to the lower edge of the battery string 1 is the first battery cell 111, then the busbar 3 is an end busbar, used to connect two adjacent battery strings 1 in the lower half. In the lower half, if the battery cell 11 closest to the upper edge of the battery string 1 is the first battery cell 111, then the busbar 3 is an intermediate busbar, used to connect the battery string 1 in parallel with the battery string 1 in the upper half. In the lower half, if both battery cells 11 at both ends of the battery string 1 are first battery cells 111, then the busbar 3 closest to the lower edge is an end busbar, and the busbar 3 closest to the upper edge is also an end busbar.

[0079] like Figure 1 As shown, in the battery assembly 100, if the battery cell 11 closest to the lower edge of the battery string 1 in the upper half is the first battery cell 111, then the busbar 3 is the middle busbar, and the battery cell 11 closest to the upper edge of the battery string 1 in the lower half is not the first battery cell 111. In this case, the battery cell 11 is the third battery cell 1211 mentioned below.

[0080] Please see Figures 1-3 In an embodiment of the present invention, the battery assembly 100 includes at least one series battery string group 110, which includes two battery strings 1 arranged along the second direction X. In the same series battery string group 110, the same bus bar 3 extends from the second battery cell 112 of one battery string 1 to the second battery cell 112 of the other battery string 1 to connect the two battery strings 1 in series in the series battery string group 110.

[0081] Thus, in the series battery string group 110, two battery strings 1 can be connected in series through the same bus bar 3, without the need to set two different bus bars 3 to connect the battery strings 1 in the series battery string group 110.

[0082] Specifically, in such an embodiment, the busbar 3 used to connect two battery strings 1 in series in the series battery string group 110 is an end busbar of the battery assembly 100. The number of end busbars is equal to the number of series battery string groups 110 in the battery assembly 100. For example, as Figure 1 As shown, the upper half has 6 battery strings 1 and 3 series-connected battery string groups 110, and the lower half also has 6 battery strings 1 and 3 series-connected battery string groups 110. Therefore, the upper half has 3 end busbars and the lower half also has 3 end busbars.

[0083] It is easy to understand that in the series battery string group 110, the first battery cells 111 in the two battery strings 1 correspond to each other (i.e., are basically aligned in the second direction X). In order to realize the series connection of the two battery strings 1, the polarity of the first solder strips 21 on the first battery cells 111 in the two battery strings 1 is opposite. That is, in the two battery strings 1 in the series battery string group 110, the first solder strip 21 of the first battery cell 111 in one battery string 1 is electrically connected to the negative main grid and / or negative fine grid on the corresponding first battery cell 111, and the first solder strip 21 on the other first battery cell 111 is electrically connected to the positive main grid and / or positive fine grid on the corresponding first battery cell 111.

[0084] In an embodiment of the present invention, the battery assembly 100 includes at least one parallel battery string group 120, the parallel battery string group 120 including a first battery string 1201 and a second battery string 1202 arranged along a first direction Y, the first battery string 1201 being located in the upper half of the assembly, and the second battery string 1202 being located in the lower half of the assembly.

[0085] In the parallel battery string group 120, the first battery cell 111 includes the battery cell 11 located in the first battery string 1201 that is closest to the second battery string 1202. The second battery string 1202 includes a third battery cell 1211, which is the battery cell 11 in the second battery string 1202 that is closest to the first battery string 1201. A first solder strip 21 connects the first battery cell 111 and the third battery cell 1211. The first battery string 1201 and the second battery string 1202 are connected in parallel through the first solder strip 21.

[0086] It is easy to understand that, in this case, when the first battery cell 111 includes the battery cell 11 located in the first battery string 1201 that is closest to the second battery string 1202, the busbar 3 on the second battery cell 112 adjacent to the first battery cell 111 is the intermediate busbar.

[0087] Thus, by setting the battery cell 11 closest to the second battery cell 1202 in the first battery string 1201 of the parallel battery string group 120 as the first battery cell 111, the first solder strip 21 on the first battery cell 111 can connect to the battery cell 11 closest to the first battery string 1201 (i.e. the third battery cell 1211 mentioned above) of the second battery string 1202 at the same time as connecting to the bus bar 3, thereby realizing the parallel connection between the first battery string 1201 and the second battery string 1202.

[0088] Specifically, in this case, the first solder strip 21 on the first battery cell 111 closest to the second battery string 1202 can extend to the third battery cell 1211 of the second battery string 1202, thereby connecting the first battery string 1201 and the second battery string 1202 in parallel to achieve parallel output of the two battery strings 1.

[0089] In addition, combined Figures 1-3 As can be seen, in the battery assembly 100 of this embodiment, the battery cell 11 closest to the second battery cell 1202 in the first battery string 1201 is the first battery cell 111, and the battery cell 11 located at the end of the first battery string 1201 away from the second battery string 1202 is also the first battery cell 111. In the second battery string 1202, the battery cell 11 closest to the first battery string 1201 is the third battery cell 1211, and the battery cell 11 located at the end of the second battery string 1202 away from the first battery string 1201 is also the first battery cell 111. That is to say, in this embodiment, the battery cells 11 at both ends of the first battery string 1201 are both first battery cells 111, the battery cell 11 at one end of the second battery string 1202 is the first battery cell 111, and the battery cell 11 at the other end of the second battery string 1202 is the third battery cell 1211.

[0090] In this embodiment, the first battery string 1201 has two first battery cells 111 and two second battery cells 112, each with two corresponding busbars 3. One of the busbars 3 is an end busbar, and the other is a middle busbar. The second battery string 1202 has only one first battery cell 111 and one second battery cell 112, each with one corresponding busbar 3, which is an end busbar 3. It is easy to understand that in this case, in the first battery string 1201, the first solder strips 21 on the two first battery cells 111 have opposite polarities. The first solder strip 21 of one first battery cell 111 is electrically connected to the negative main grid and / or negative fine grid on the corresponding first battery cell 111, and the first solder strip 21 of the other first battery cell 111 is electrically connected to the positive main grid and / or positive fine grid on the corresponding first battery cell 111. For example, the polarity of the first solder strip 21 on the first battery cell 111 in the second battery string 1202 is opposite to that of the first solder strip 21 on the first battery cell 111 in the first battery string 1201 that is closest to the first battery cell 111 on the second battery string 1202.

[0091] In summary, in the embodiments of this utility model, in the battery assembly 100, the busbar 3 includes an end busbar and an intermediate busbar, and the specific type of the busbar 3 depends on the specific location where the busbar 3 is set.

[0092] Please see Figures 1-3 In some embodiments, the insulating strip 4 extends to a portion of the first battery cell 111 on the side near the second battery cell 112.

[0093] Thus, by setting the width of the insulating strip 4 to be relatively wide and extending it to the first battery cell 111, it can effectively prevent the busbar 3 from shifting and coming into contact with the third solder strip 23 on the first battery cell 111, which would cause a short circuit.

[0094] In some embodiments, the battery assembly 100 includes a plurality of series battery strings 110 arranged along a second direction X, wherein an insulating strip 4 extends from the first series battery string 110 to the last series battery string 110 in the second direction X.

[0095] Thus, in the series battery string group 110 in the same row, only one insulating strip 4 is needed to insulate and isolate all the busbars 3, instead of each busbar 3 in each series battery string group 110 needing to be individually equipped with an insulating strip 4, reducing the difficulty of manufacturing and coating.

[0096] This utility model embodiment also provides a photovoltaic system, which includes the battery module 100 of the above embodiment. It should be noted that the photovoltaic system has the same or similar beneficial effects as the battery module, and the related parts between the two can be referred to each other. To avoid repetition, they will not be described again here.

[0097] 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. It 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.

[0098] In the description of this specification, references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0099] The above are merely preferred embodiments of the present utility model and are 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, include: A plurality of battery strings, each battery string comprising a plurality of battery cells connected in series along a first direction, each battery cell comprising a first battery cell disposed at an end of the battery string and a second battery cell adjacent to the first battery cell, the back of the first battery cell having a plurality of first solder strips and a plurality of third solder strips alternately arranged along a second direction, the back of the second battery cell having a plurality of second solder strips and a plurality of fourth solder strips alternately arranged along the second direction, the second solder strips corresponding one-to-one with the first solder strips, the third solder strips corresponding one-to-one with the fourth solder strips and being electrically connected, the second direction intersecting the first direction; and A busbar is disposed on the back of the second battery cell, the busbar extends along the second direction, the first solder strip extends toward the second battery cell and connects to the busbar, and the second solder strip and the fourth solder strip are spaced apart from the busbar; The second battery cell includes a first edge and a second edge disposed opposite to each other along the first direction, the first edge being disposed closer to the first battery cell than the second edge, and the second solder strip including a first end extending relative to the busbar toward the first battery cell; wherein the distance from the first end to the first edge is d1, the distance from the busbar to the first edge is d2, and 0.2≦d1 / d2≤0.

7.

2. The battery assembly according to claim 1, characterized in that, 0.5≦d1 / d2≤0.

6.

3. The battery assembly according to claim 1, characterized in that, d1 is 1.5mm to 3.5mm, and d2 is 3mm to 15mm.

4. The battery assembly according to claim 1, characterized in that, The battery assembly also includes: An insulating strip is located between the busbar and the second battery cell.

5. The battery assembly according to claim 1, characterized in that, The first solder strip includes: The main body portion located on the first battery cell; A bent portion connected to the main body and bent away from the direction of the second weld strip; and A connecting part connected to the bending portion, the connecting part being connected to the busbar.

6. The battery assembly according to claim 5, characterized in that, The connecting part is connected to the surface of the busbar away from the second battery cell, and the length of the overlap between the connecting part and the busbar is greater than half the length of the busbar in the first direction.

7. The battery assembly according to claim 6, characterized in that, The length of the overlap between the connecting part and the busbar is less than the length of the busbar in the first direction.

8. The battery assembly according to claim 1, characterized in that, The second battery cell includes a third edge and a fourth edge disposed opposite to each other along the second direction. The third edge is disposed closer to the end of the busbar than the fourth edge. The distance from the end of the busbar to the third edge is d3, where d3 is 2mm to 12mm.

9. The battery assembly according to claim 1, characterized in that, The second battery cell is provided with a plurality of pads that connect to the second solder strip, and the pad closest to the first edge is located below the busbar.

10. The battery assembly according to claim 1, characterized in that, The ratio of the width to the thickness of the busbar is 15 to 55.

11. The battery assembly according to claim 1, characterized in that, The battery assembly includes at least one series battery string group, which includes two battery strings arranged along the second direction. In the same series battery string group, the same busbar extends from the second cell of one battery string to the second cell of the other battery string to connect the two battery strings in the series battery string group in series.

12. The battery assembly according to claim 1 or 11, characterized in that, The battery assembly includes at least one parallel battery string group, which includes a first battery string and a second battery string arranged along the first direction. In the parallel battery string group, the first battery cell includes the battery cell located in the first battery string that is closest to the second battery string, the second battery string includes a third battery cell that is the battery cell in the second battery string that is closest to the first battery string, the first solder strip connects the first battery cell and the third battery cell, and the first battery string and the second battery string are connected in parallel through the first solder strip.

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

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