Battery assembly and photovoltaic system

Abstract

The utility model is suitable for the technical field of solar cells, and provides a cell assembly and a photovoltaic system. In the battery assembly provided by the utility model, the sum of two included angles formed by a first joint and a second joint of a first junction box and a joint closest to the first junction box in a first battery string and a joint closest to the first junction box in a second battery string is smaller than those formed by third joints and second joints in other second junction boxes. And the four joints are respectively the sum of two included angles formed by the connecting part, closest to the second junction box, in the third battery string and the connecting part, closest to the second junction box, in the fourth battery string. Therefore, in the battery assembly provided by the utility model, each junction box can be connected to different positions of the adjacent battery strings, that is, a plurality of connection modes of the junction boxes and the battery strings exist, and the effect of improving the flexibility of the connection of the junction boxes and the battery strings is achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of solar cells, in particular to a battery module and a photovoltaic system. Background Art

[0002] Back-contact solar cells are a type of solar cell design, characterized in that the electrodes of the cell are designed on the back of the cell, rather than the traditional front design. This design can reduce the shadow area on the cell surface and improve the photoelectric conversion efficiency. In the case of traditional front-contact solar cells, when the electrodes need to cover the cell surface, it may hinder the absorption of light and the transport of charges, while the back-contact design can reduce these losses.

[0003] In a back-contact solar cell module, a junction box is provided, and the junction box is respectively connected to adjacent battery strings. However, in the prior art, in the battery module, each junction box is usually only connected to a specific position of the adjacent battery string, and the connection method between the junction box and the battery string is relatively single, lacking flexibility. Summary of the Utility Model

[0004] The utility model provides a battery module and a photovoltaic system, aiming to solve the technical problem of the relatively single connection method between the junction box and the battery string in the prior art.

[0005] The present utility model is implemented as follows. The battery assembly of the embodiment of the present utility model includes: a first junction box having a first connector and a second connector; an adjacent first battery string and a second battery string, the first battery string is connected to the first connector through a first bus bar, and the second battery string is connected to the second connector through a second bus bar; at least one second junction box having a third connector and a fourth connector; at least one group of adjacent third battery strings and fourth battery strings, the second battery string is connected to the third connector through a third bus bar, and the fourth battery string is connected to the fourth connector through a fourth bus bar; wherein, the included angle formed by the connection line between the connection point of the first battery string and the first bus bar closest to the first junction box and the first connector and the connection line between the first connector and the second connector is a first included angle; the included angle formed by the connection line between the connection point of the second battery string and the second bus bar closest to the first junction box and the second connector and the connection line between the second connector and the first connector is a second included angle; the included angle formed by the connection line between the connection point of the third battery string and the third bus bar closest to the second junction box and the third connector and the connection line between the third connector and the second connector is a third included angle; the included angle formed by the connection line between the connection point of the fourth battery string and the fourth bus bar closest to the second junction box and the fourth connector and the connection line between the third connector and the fourth connector is a fourth included angle; the sum of the first included angle and the second included angle is less than the sum of the third included angle and the fourth included angle.

[0006] Further, the first solder tape is the solder tape in the first battery string closest to the first junction box; the connection point of the first battery string and the first bus bar closest to the first junction box is located on the first solder tape; the second solder tape is the solder tape in the second battery string closest to the first junction box; the connection point of the second battery string and the second bus bar closest to the first junction box is located on the second solder tape.

[0007] Further, the third solder tape is the second solder tape in the third battery string closest to the second junction box; the connection point of the third battery string and the third bus bar closest to the second junction box is located on the third solder tape; the fourth solder tape is the second solder tape in the fourth battery string closest to the second junction box, and the connection point of the fourth battery string and the fourth bus bar closest to the second junction box is located on the fourth solder tape.

[0008] Further, the third solder strip is the one closest to the second junction box in the third battery string; the connection between the third battery string and the third busbar closest to the second junction box is located on the third solder strip; the fourth solder strip is the second closest to the second junction box in the fourth battery string, and the connection between the fourth battery string and the fourth busbar closest to the second junction box is located on the fourth solder strip.

[0009] Further, the first joint and the second joint are symmetrical about an axis of symmetry of the first junction box.

[0010] Further, the connection between the first battery string and the first busbar closest to the first junction box and the connection between the second battery string and the second busbar closest to the first junction box are symmetrical about an axis of symmetry of the first junction box.

[0011] Further, the third joint and the fourth joint are symmetrical about an axis of symmetry of the second junction box.

[0012] Further, the connection between the third battery string and the third busbar closest to the second junction box and the connection between the fourth battery string and the fourth busbar closest to the second junction box are symmetrical about an axis of symmetry of the second junction box.

[0013] Further, the first joint and the second joint have opposite polarities.

[0014] Further, the third joint and the fourth joint have opposite polarities.

[0015] Further, both the first battery string and the second battery string are A-strings.

[0016] Further, both the first battery string and the second battery string are B-strings.

[0017] The present utility model also provides a photovoltaic system, which includes the above-mentioned battery module.

[0018] In the battery module and the photovoltaic system of the embodiments of the present utility model, among the battery modules of the present utility model, the sum of the two included angles formed by the first connector and the second connector of the first junction box with the connection points closest to the first junction box in the first battery string and the connection points closest to the first junction box in the second battery string respectively is less than the sum of the two included angles formed by the third connector and the fourth connector of each of the other second junction boxes with the connection points closest to the second junction box in the third battery string and the connection points closest to the second junction box in the fourth battery string respectively. Therefore, in the battery module of the present utility model, each junction box can be connected to different positions of adjacent battery strings, that is, there are multiple connection methods between the junction box and the battery string, achieving the effect of improving the flexibility of the connection between the junction box and the battery string.

[0019] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present utility model. Description of the Drawings

[0020] Figure 1 is a schematic diagram of a module of the photovoltaic system provided by an embodiment of the present utility model;

[0021] Figure 2 is a schematic plan view of the battery module provided by an embodiment of the present utility model;

[0022] Figure 3 is Figure 2 a schematic connection structure diagram of the first junction box in the battery module described above;

[0023] Figure 4 is Figure 2 a schematic connection structure diagram of one of the second junction boxes in the battery module described above;

[0024] Figure 5 is Figure 2 a schematic connection structure diagram of another second junction box in the battery module described above.

[0025] Main element symbol description: 1000, photovoltaic system; 100, battery module; 10, first junction box; 11, first connector; 12, second connector; 20, second junction box; 21, third connector; 22, fourth connector; 30, first battery string; 31, first solder strip; 40, second battery string; 41, second solder strip; 50, third battery string; 51, third solder strip; 60, fourth battery string; 61, fourth solder strip; 71, first bus bar; 72, second bus bar; 73, third bus bar; 74, fourth bus bar; Q1, first included angle; Q2, second included angle; Q3, third included angle; Q4, fourth included angle. Detailed Embodiments

[0026] In order to make the objectives, technical solutions and advantages of the present utility model clearer and more understandable, the present utility model will be further described in detail below in conjunction with the accompanying drawings and embodiments. The embodiments described below by referring to the accompanying drawings are exemplary and are only used to explain the present utility model and cannot be construed as a limitation to the present utility model. In addition, it should be understood that the specific embodiments described herein are only used to explain the present utility model and are not used to limit the present utility model.

[0027] In the description of the present utility model, it should be understood that the orientation or positional relationship indicated by terms such as "length", "width", "upper", "lower", "top", "bottom", "lateral", "longitudinal", etc. is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be construed as a limitation to the present utility model.

[0028] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of the described features. In the description of the present utility model, the meaning of "a plurality" is two or more unless otherwise specifically defined.

[0029] In the description of the present utility model, it should be noted that unless otherwise clearly specified and limited, the terms "installed", "connected" and "connected" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection or an integral connection; it may be a mechanical connection, an electrical connection or a connection that can communicate with each other; it may be directly connected or indirectly connected through an intermediate medium, and it may be the internal communication of two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.

[0030] In the present utility model, unless otherwise clearly specified and limited, the first feature being "above" or "below" the second feature may include the direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through other features therebetween. Moreover, the first feature being "above", "over" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "under" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0031] The following disclosure provides many different embodiments or examples for implementing different structures of the present utility model. To simplify the disclosure of the present utility model, components and settings of specific examples are described below. Of course, they are merely examples and are not intended to limit the present utility model. In addition, the present utility model may repeat reference numerals and / or reference letters in different examples. Such repetition is for the purpose of simplification and clarity and does not itself indicate the relationship between various embodiments and / or settings discussed. In addition, the present utility model provides examples of various specific processes and materials, but those of ordinary skill in the art may be aware of the application of other processes and / or the use scenarios of other materials.

[0032] Please refer to Figure 1 , the photovoltaic system 1000 in the embodiment of the present utility model may include the battery module 100 in the embodiment of the present utility model. The battery module 100 in the embodiment of the present utility model may include several battery strings. Each battery string may include a plurality of back-contact batteries. Each contact battery may be sequentially connected in series through welding strips to form a battery string. Each battery string in the battery module 100 may be connected in series, in parallel, or in a series-parallel combination to achieve the current collection output. For example, the connection between each battery string may be achieved through a bus bar.

[0033] Please refer to Figure 2 , the battery module 100 in the embodiment of the present utility model may include a first junction box 10, adjacent first battery string 30 and second battery string 40, a first bus bar 71, a second bus bar 72, at least one second junction box 20, at least one group of adjacent third battery string 50 and fourth battery string 60, a third bus bar 73, and a fourth bus bar 74.

[0034] The first battery string 30 and the second battery string 40 are specifically the battery strings adjacent to the first junction box 10, and the first battery string 30 and the second battery string 40 are respectively arranged on both sides of the first junction box 10. The first junction box 10 is arranged between the first battery string 30 and the second battery string 40. The first junction box 10 is respectively connected to the adjacent first battery string 30 and second battery string 40. The first junction box 10 has a first connector 11 and a second connector 12. The first battery string 30 is connected to the first connector 11 of the first junction box 10 through the first bus bar 71. The second battery string 40 is connected to the second connector 12 of the second junction box 20 through the second bus bar 72. The first bus bar 71 is respectively connected to the first junction box 10 and the first battery string 30. The second bus bar 72 is respectively connected to the first junction box 10 and the second battery string 40.

[0035] The third battery string 50 and the fourth battery string 60 are specifically the battery strings adjacent to the second junction box 20. One third battery string 50 and one fourth battery string 60 are respectively arranged on both sides of one second junction box 20, and one second junction box 20 is arranged between one third battery string 50 and one fourth battery string 60. The second junction box 20 is respectively connected to a group of adjacent third battery string 50 and fourth battery string 60. The second junction box 20 has a third connector 21 and a fourth connector 22. The third battery string 50 is connected to the third connector 21 of the second junction box 20 through a third bus bar 73, and the fourth battery string 60 is connected to the fourth connector 22 of the second junction box 20 through a fourth bus bar 74. The third bus bar 73 is respectively connected to the second junction box 20 and the third battery string 50, and the fourth bus bar 74 is respectively connected to the second junction box 20 and the fourth battery string 60.

[0036] When the battery string is connected to the bus bar, there are multiple connection points between the battery string and the bus bar, that is, there are multiple connection points between the first battery string 30 and the first bus bar 71. Among them, the included angle formed by the connection line between the connection point of the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the first connector 11 and the connection line between the first connector 11 and the second connector 12 is the first included angle Q1; the included angle formed by the connection line between the connection point of the second battery string 40 and the second bus bar 72 closest to the first junction box 10 and the second connector 12 and the connection line between the second connector 12 and the first connector 11 is the second included angle Q2; the included angle formed by the connection line between the connection point of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the third connector 21 and the connection line between the third connector 21 and the second connector 12 is the third included angle Q3; the included angle formed by the connection line between the connection point of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 and the fourth connector 22 and the connection line between the third connector 21 and the fourth connector 22 is the fourth included angle Q4.

[0037] The sum of the first included angle Q1 and the second included angle Q2 is less than the sum of the third included angle Q3 and the fourth included angle Q4.

[0038] Specifically, in the battery module 100, adjacent battery strings are respectively connected to the junction box, and the junction box is respectively connected to the adjacent battery strings. The battery string is specifically connected to the connector of the junction box through the bus bar. In the battery module 100, there is a structure in which multiple junction boxes are connected to adjacent battery strings. In the prior art, for the structure in which each junction box is connected to adjacent battery strings, each junction box is usually only connected to a specific position of the adjacent battery string, and the included angle formed between the two connectors of each junction box and the connection point of the battery string is usually the same. The connection method between the junction box and the battery string is relatively single and lacks flexibility.

[0039] In the battery module 100 of the present utility model, the sum of the two included angles formed by the first connector 11 and the second connector 12 of the first junction box 10 with the connection points closest to the first junction box 10 in the first battery string 30 and the second battery string 40 respectively is less than the sum of the two included angles formed by the third connector 21 and the fourth connector 22 of each of the other second junction boxes 20 with the connection points closest to the second junction box 20 in the third battery string 50 and the fourth battery string 60 respectively. In the traditional battery module 100, the sum of the first included angle Q1 and the second included angle Q2 is usually equal to the sum of the third included angle Q3 and the fourth included angle Q4. However, in the battery module 100 of the present utility model, the included angles formed between the two connectors of each junction box and the connection points of the battery strings are not completely the same, and the sum of the first included angle Q1 and the second included angle Q2 is not equal to the sum of the third included angle Q3 and the fourth included angle Q4. That is, in the battery module 100 of the present utility model, there are at least two connection methods between the junction box and its adjacent battery strings. Therefore, in the battery module 100 of the present utility model, each junction box can be connected to different positions of the adjacent battery strings, that is, there are multiple connection methods between the junction box and the battery strings, achieving the effect of improving the flexibility of the connection between the junction box and the battery strings.

[0040] Therefore, in the present utility model, by setting the sum of the first included angle Q1 and the second included angle Q2 formed by the first junction box 10 to be less than the sum of the third included angle Q3 and the fourth included angle Q4 formed by the other second junction boxes 20, that is, making the first included angle Q1 and the second included angle Q2 different from the sum of the other third included angle Q3 and the fourth included angle Q4, the effect of improving the flexibility of the connection between the junction box and the battery strings is achieved, and the structure of the battery module 100 can also be made more compact, achieving the effect of improving the assembly density and space utilization rate of the battery module 100.

[0041] Furthermore, as Figure 2 and Figure 3 shown, in this battery module 100, the first connector 11 and the second connector 12 of the first junction box 10 are symmetrical with respect to an axis of symmetry of the first junction box 10; the third connector 21 and the fourth connector 22 of the second junction box 20 are symmetrical with respect to an axis of symmetry of the second junction box 20.

[0042] Specifically, for the specific structure of the first junction box 10, the first connector 11 and the second connector 12 in the first junction box 10 can be specifically symmetrical about an axis of symmetry of the first junction box 10, and this axis of symmetry can specifically be the axis of symmetry of the first junction box 10 in the first direction. Similarly, for the specific structure of the second junction box 20, the third connector 21 and the fourth connector 22 in the second junction box 20 can be specifically symmetrical about an axis of symmetry of the second junction box 20, and this axis of symmetry can specifically be the axis of symmetry of the second junction box 20 in the first direction.

[0043] In addition, in the first junction box 10, the polarities of the first connector 11 and the second connector 12 are opposite, that is, the polarities of the solder tapes connected to the first bus bar 71 and the solder tapes connected to the second bus bar 72 are also opposite.

[0044] Furthermore, as Figure 2 and Figure 3 shown, for the specific connection structure of the first junction box 10 with the first battery string 30 and the second battery string 40. Multiple solder tapes are welded in the battery string. The first solder tape 31 is the solder tape closest to the first junction box 10 in the first battery string 30; the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 is located on the first solder tape 31; the second solder tape 41 is the solder tape closest to the first junction box 10 in the second battery string 40; the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 is located on the second solder tape 41.

[0045] Specifically, in the first battery string 30, along the second direction, multiple solder tapes welded to the first battery string 30 are provided, and some of these solder tapes are connected to the first bus bar 71. The first solder tape 31 is welded and arranged in the first battery string 30 and is welded to the first bus bar 71 for connection. The first solder tape 31 is the solder tape closest to the first junction box 10 in the first battery string 30, and the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 is located on the first solder tape 31.

[0046] The first direction is perpendicular to the second direction. The first direction can be the longitudinal direction in Figures 2 to 4 and the second direction can be the transverse direction in Figures 2 to 4 . In other embodiments, the first direction and the second direction can also be arranged diagonally, which is not limited herein.

[0047] Similarly, in the second battery string 40, along the second direction, a plurality of solder tapes welded to the second battery string 40 are provided, and some of these solder tapes are connected to the second bus bar 72. The second solder tape 41 is welded and arranged in the second battery string 40 and is welded to the second bus bar 72 and connected to the second bus bar 72. The second solder tape 41 is the solder tape closest to the second junction box 20 in the second battery string 40. The connection between the second battery string 40 and the second bus bar 72 closest to the second junction box 20 is located on the second solder tape 41.

[0048] Moreover, in each included angle in the present invention: the first included angle Q1, the second included angle Q2, the third included angle Q3, and the fourth included angle Q4 are all formed by the joints of the junction box and the connection points of each battery string and the corresponding bus bar. In actual applications, the specifications of each junction box are the same, so the distance between the connecting lines of the two joints of each junction box is also the same. Then one side length of each included angle is the same, and the angle of each included angle is determined by the other side length, that is, the connecting line between the connection point of each joint and each battery string. In the present invention, the shorter the connecting line length between the joint of the junction box and the connection point of the battery string, the smaller the formed included angle.

[0049] Therefore, the first solder tape 31 is the solder tape closest to the first junction box 10 in the first battery string 30, and the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 is also located on the first solder tape 31; the second solder tape 41 is the solder tape closest to the first junction box 10 in the second battery string 40, and the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 is also located on the second solder tape 41. Thus, the sum of the first included angle Q1 and the second included angle Q2 can be minimized.

[0050] Moreover, in the present invention, by setting the first solder tape 31 as the solder tape closest to the first junction box 10 in the first battery string 30, and the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 is located on the first solder tape 31; by setting the second solder tape 41 as the solder tape closest to the first junction box 10 in the second battery string 40, and the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 is located on the second solder tape 41, the structure of the battery module 100 can be made more compact, and further the effect of improving the assembly density and space utilization rate of the battery module 100 can be achieved.

[0051] And, in a possible implementation manner, the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 are symmetrical about an axis of symmetry of the first junction box 10.

[0052] Specifically, when the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 is located on the first solder tape 31, and the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 is located on the second solder tape 41. At this time, since the first solder tape 31 and the second solder tape 41 are symmetrical about an axis of symmetry of the first junction box 10, the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 are also symmetrical about an axis of symmetry of the first junction box 10, and this axis of symmetry is the same as the axis of symmetry of the first terminal 11 and the second terminal 12 in the first junction box 10.

[0053] Therefore, by setting the symmetry of the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the connection between the first battery string 30 and the second bus bar 72 closest to the first junction box 10, it can be ensured that the current is evenly distributed between the first battery string 30 and the second battery string 40, and the performance unevenness and the risk of thermal runaway caused by asymmetric current distribution can be reduced, improving the stability of the battery module 100.

[0054] In addition, in the battery module 100 of the present utility model, by setting the connection between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 to be located on the first solder tape 31, and the first solder tape 31 is the solder tape closest to the first junction box 10 in the first battery string 30; and by setting the connection between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 to be located on the second solder tape 41, and the second solder tape 41 is the solder tape closest to the second junction box 20 in the second battery string 40. In such a case, the two terminals of the junction box can be connected to the solder tapes closest to the edges of the adjacent battery strings through the bus bars, that is, it is possible to realize that different types of battery strings do not need to be used in the production of the battery module 100 (that is, cancel the A string and B string categories in the module production process), which can improve the production efficiency of the battery module 100. That is, there can be battery strings where both the first battery string 30 and the second battery string 40 are A strings; or, similarly, there can also be battery strings where both the first battery string 30 and the second battery string 40 are B strings.

[0055] Furthermore, as Figure 2 and Figure 4As shown, for the specific connection structure between the second junction box 20 and the third battery string 50 and the fourth battery string 60. Multiple solder tapes are welded in the battery string. The third solder tape 51 is the second solder tape closest to the second junction box 20 in the third battery string 50; the connection between the third battery string 50 and the third bus bar 73 closest to the second junction box 20 is located on the third solder tape 51; the fourth solder tape 61 is the solder tape closest to the second junction box 20 in the fourth battery string 60; the second connection between the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 is located on the fourth solder tape 61.

[0056] Specifically, in the third battery string 50, along the second direction, multiple solder tapes welded to the third battery string 50 are provided, and some of these solder tapes are connected to the third bus bar 73. The third solder tape 51 is welded and arranged in the third battery string 50 and is welded to the third bus bar 73 and connected to the third bus bar 73. The third solder tape 51 is the second solder tape closest to the second junction box 20 in the third battery string 50, and the connection between the third battery string 50 and the third bus bar 73 closest to the first junction box 10 is located on the third solder tape 51. In addition, in a possible implementation, the first solder tape 31 and the third solder tape 51 may be the same solder tape, or of course the first solder tape 31 and the third solder tape 51 may also be two different solder tapes, which is not limited here; the second solder tape 41 and the fourth solder tape 61 may be the same solder tape, or of course the second solder tape 41 and the fourth solder tape 61 may also be two different solder tapes, which is not limited here.

[0057] Similarly, in the fourth battery string 60, along the second direction, multiple solder tapes welded to the fourth battery string 60 are provided, and some of these solder tapes are connected to the fourth bus bar 74. The fourth solder tape 61 is welded and arranged in the fourth battery string 60 and is welded to the fourth bus bar 74 and connected to the fourth bus bar 74. The fourth solder tape 61 is the second solder tape closest to the second junction box 20 in the fourth battery string 60, and the connection between the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 is located on the second solder tape 41.

[0058] Therefore, in the present utility model, the connection points of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the connection points of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 are respectively located on the solder tapes of the third battery string 50 that are the second closest to the second junction box 20 and on the solder tapes of the fourth battery string 60 that are the second closest to the second junction box 20. Compared with the connection mode in which the connection points of the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the connection points of the second battery string 40 and the second bus bar 72 closest to the first junction box 10 are respectively located on the solder tapes of the first battery string 30 that are the closest to the first junction box 10 and on the solder tapes of the second battery string 40 that are the closest to the second junction box 20, the sum of the first angle Q1 and the second angle Q2 is less than the sum of the third angle Q3 and the fourth angle Q4.

[0059] Moreover, in the battery module 100 of the present utility model, various connection modes between the junction box and the adjacent battery strings can be simultaneously provided, achieving the effect of improving the flexibility of the connection between the junction box and the battery strings.

[0060] Furthermore, in a possible implementation manner, the connection points of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the connection points of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 are symmetrical about an axis of symmetry of the second junction box 20.

[0061] Specifically, when the connection point of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 is located on the third solder tape 51 and the connection point of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 is located on the fourth solder tape 61. At this time, since the third solder tape 51 and the fourth solder tape 61 are symmetrical about an axis of symmetry of the second junction box 20, the connection point of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the connection point of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 are also symmetrical about an axis of symmetry of the second junction box 20, and this axis of symmetry is the same axis of symmetry as the axis of symmetry of the third connector 21 and the fourth connector 22 in the second junction box 20.

[0062] Therefore, by setting the symmetry of the connection points of the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the connection points of the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20, it is possible to ensure that the current is evenly distributed between the third battery string 50 and the fourth battery string 60, achieving the effect of reducing the performance unevenness and the risk of thermal runaway that may be caused by asymmetric current distribution and improving the stability of the battery module 100.

[0063] Further, for the specific connection structure between the second junction box 20 and the third battery string 50 and the fourth battery string 60, in addition to the connection manner as shown in Figure 4 . As shown in Figure 5 , in a possible implementation manner, the third solder strip 51 is the solder strip closest to the second junction box 20 in the third battery string 50; the connection point between the third battery string 50 and the third bus bar 73 closest to the second junction box 20 is located on the third solder strip 51; the fourth solder strip 61 is the second solder strip closest to the second junction box 20 in the fourth battery string 60, and the connection point between the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 is located on the fourth solder strip 61.

[0064] Specifically, in the third battery string 50, along the second direction, there are multiple solder strips welded to the third battery string 50, and some of these solder strips are connected to the third bus bar 73. The third solder strip 51 is welded and arranged in the third battery string 50 and is welded to the third bus bar 73 for connection. The third solder strip 51 is the solder strip closest to the second junction box 20 in the third battery string 50, and the connection point between the third battery string 50 and the third bus bar 73 closest to the first junction box 10 is located on the third solder strip 51.

[0065] Similarly, in the fourth battery string 60, along the second direction, there are multiple solder strips welded to the fourth battery string 60, and some of these solder strips are connected to the fourth bus bar 74. The fourth solder strip 61 is welded and arranged in the fourth battery string 60 and is welded to the fourth bus bar 74 for connection. The fourth solder strip 61 is the second solder strip closest to the second junction box 20 in the fourth battery string 60, and the connection point between the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 is located on the second solder strip 41.

[0066] Therefore, in the present utility model, by setting the connection manner that the connection point between the third battery string 50 and the third bus bar 73 closest to the second junction box 20 and the connection point between the fourth battery string 60 and the fourth bus bar 74 closest to the second junction box 20 are respectively located on the solder strip closest to the second junction box 20 in the third battery string 50 and the second solder strip closest to the second junction box 20 in the fourth battery string 60. Compared with the connection manner that the connection point between the first battery string 30 and the first bus bar 71 closest to the first junction box 10 and the connection point between the second battery string 40 and the second bus bar 72 closest to the first junction box 10 are respectively located on the solder strip closest to the first junction box 10 in the first battery string 30 and the solder strip closest to the second junction box 20 in the second battery string 40, it is such that in the battery module 100, the sum of the first included angle Q1 and the second included angle Q2 is less than the sum of the third included angle Q3 and the fourth included angle Q4.

[0067] Therefore, in the battery module 100 of the present utility model, various connection methods between the junction box and the adjacent battery strings can be combined, achieving the effect of improving the flexibility of the connection between the junction box and the battery strings.

[0068] Of course, Figure 4 and Figure 5 the two connection methods between the second junction box 20 and the adjacent battery strings in [relevant content not provided] can exist in one battery module 100. That is, in the battery module 100 of the present utility model, at least three connection methods between the junction box and its adjacent battery strings can exist. Therefore, in the battery module 100 of the present utility model, various connection methods between the junction box and the adjacent battery strings can be combined, achieving the effect of improving the flexibility of the connection between the junction box and the battery strings.

[0069] In the description of this specification, the descriptions with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. mean that the specific features, structures, materials, or characteristics described in connection with the said embodiment or example are included in at least one embodiment or example of the present utility model. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0070] Although the embodiments of the present utility model have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present utility model, and the scope of the present utility model is defined by the claims and their equivalents.

Claims

1. A battery assembly, characterized in that: include: A first junction box, the first junction box having a first connector and a second connector; A first battery string and a second battery string are adjacent to each other, wherein the first battery string is connected to the first connector via a first bus bar, and the second battery string is connected to the second connector via a second bus bar; at least one second junction box, the second junction box having a third connection and a fourth connection; at least one group of adjacent third battery string and fourth battery string, wherein the second battery string is connected to the third connector via a third bus bar, and the fourth battery string is connected to the fourth connector via a fourth bus bar; The angle formed by the connection between the first battery string and the first bus bar closest to the first junction box and the first connector and the connection between the first connector and the second connector is the first angle; An angle formed by a line between a connection point between the second battery string and the second bus bar closest to the first junction box and the second connector and a line between the second connector and the first connector is a second angle; The angle formed by the connection line between the connection point between the third battery string and the third bus bar closest to the second junction box and the third connector and the connection line between the third connector and the second connector is the third angle; An angle formed by a line between a connection point between the fourth battery string and the fourth bus bar closest to the second junction box and the fourth connector and a line between the third connector and the fourth connector is a fourth angle; The sum of the first angle and the second angle is smaller than the sum of the third angle and the fourth angle.

2. The battery assembly according to claim 1, characterized in that: The first welding strip is the welding strip in the first battery string that is closest to the first junction box; the connection between the first battery string and the first bus bar that is closest to the first junction box is located on the first welding strip; The second welding strip is the welding strip in the second battery string that is closest to the first junction box; the connection between the second battery string and the second bus bar that is closest to the first junction box is located on the second welding strip.

3. The battery assembly according to any one of claims 1 or 2, characterized in that: The third welding strip is the welding strip in the third battery string that is the second closest to the second junction box; the connection between the third battery string and the third bus bar that is closest to the second junction box is located on the third welding strip; The fourth welding strip is the welding strip in the fourth battery string that is second closest to the second junction box, and the connection point between the fourth battery string and the fourth bus bar that is closest to the second junction box is located on the fourth welding strip.

4. The battery assembly according to any one of claims 1 or 2, characterized in that: The third welding strip is the welding strip in the third battery string that is closest to the second junction box; the connection between the third battery string and the third bus bar that is closest to the second junction box is located on the third welding strip; The fourth welding strip is the welding strip in the fourth battery string that is second closest to the second junction box, and the connection point between the fourth battery string and the fourth bus bar that is closest to the second junction box is located on the fourth welding strip.

5. The battery assembly according to any one of claims 1 or 2, characterized in that: The first connector and the second connector are symmetrical with respect to a symmetry axis of the first junction box.

6. The battery assembly according to claim 2, characterized in that: A connection point between the first battery string and the first bus bar closest to the first junction box and a connection point between the second battery string and the second bus bar closest to the first junction box are symmetrical with respect to a symmetry axis of the first junction box.

7. The battery assembly according to any one of claims 1 or 2, characterized in that: The third connector and the fourth connector are symmetrical with respect to a symmetry axis of the second junction box.

8. The battery assembly according to claim 3, characterized in that: A connection point between the third battery string and the third bus bar closest to the second junction box and a connection point between the fourth battery string and the fourth bus bar closest to the second junction box are symmetrical with respect to a symmetry axis of the second junction box.

9. The battery assembly according to any one of claims 1 or 2, characterized in that: The polarities of the first connector and the second connector are opposite.

10. The battery assembly according to any one of claims 1 or 2, characterized in that: The third connector and the fourth connector have opposite polarities.

11. The battery assembly according to claim 2, characterized in that: The first battery string and the second battery string are both A strings.

12. The battery assembly according to claim 2, characterized in that: The first battery string and the second battery string are both B strings.

13. A photovoltaic system, characterized in that: A battery assembly comprising several battery components as claimed in any one of claims 1 to 12.

Images