Interconnection structure of battery assembly, battery assembly and photovoltaic system

Abstract

The application is suitable for the field of photovoltaic technology, and provides an interconnection structure of a cell module, a cell module and a photovoltaic system, comprising: a busbar, the busbar extends along a first direction, the busbar has a plurality of hollow areas in the first direction; a plurality of first solder strips, the plurality of first solder strips are arranged at intervals in the first direction and extend along a second direction, each first solder strip is connected to the busbar, at least part of at least one of the first solder strip and the second solder strip is arranged in the hollow area, the hollow area can be used as an embedding space of the solder strip, in the welding or laminating process, the solder strip can slightly sink (partially sink into the hollow area) in the hollow area, thereby reducing the local laminated height of the solder strip and the busbar, and further reducing the risk of cell piece hidden cracking in the laminating process of the photovoltaic module.

Description

Technical Field

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

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

[0003] In related technologies, multiple solar cells are strung together with solder ribbons to form a solar cell string. The solar cell strings are then connected by busbars to form a solar cell module. The solder ribbons and busbars are stacked, and if the overlap area is too thick in some places, stress concentration will occur in the overlap area during the lamination process of the photovoltaic module, which may lead to solar cell fragmentation or microcracks. Utility Model Content

[0004] This application provides an interconnection structure for a battery module, which aims to solve the problem of stress concentration in the overlapping area during the lamination process of photovoltaic modules, which can lead to cell fragmentation or microcracks.

[0005] In a first aspect, this application provides an interconnection structure for a battery assembly, comprising: a busbar extending along a first direction, the busbar having a plurality of hollow areas in the first direction; a plurality of first solder strips spaced apart in the first direction and extending along a second direction, each first solder strip connected to the busbar; a plurality of second solder strips spaced apart in the first direction and extending along the second direction, each second solder strip connected to the busbar; at least a portion of at least one of the first solder strips and the second solder strips correspondingly overlapping the hollow areas of the busbar.

[0006] This application sets multiple hollow areas in the busbar, and at least one of the first and second solder strips overlaps with the hollow areas. The hollow areas can serve as embedding spaces for the solder strips. During welding or lamination, the solder strips can sink slightly (partially sink into the hollow areas) in the hollow areas, thereby reducing the local stacking height between the solder strips and the busbar, and thus reducing the risk of microcracks in the solar cells during the lamination of photovoltaic modules.

[0007] Optionally, at least a portion of each of the first and second solder strips overlaps with the cutout area of ​​the busbar.

[0008] Optionally, a plurality of first solder strips and a plurality of second solder strips are staggered in a one-to-one correspondence in the first direction, and at least a portion of one of the first solder strips and the second solder strips overlaps with the hollowed-out area of ​​the busbar.

[0009] Optionally, a plurality of first solder strips and a plurality of second solder strips are aligned one-to-one in the first direction, at least a portion of one of the first solder strips and the second solder strips overlaps with the hollow area of ​​the busbar, and the other of the first solder strips and the second solder strips has a bent section, the bent section being staggered with the hollow area of ​​the busbar. Optionally, the busbar has through holes forming the hollowed-out area.

[0010] Optionally, the ratio of the maximum diameter of the through hole to the width of the manifold ranges from 10% to 80%.

[0011] In a second aspect, a battery assembly includes the interconnection structure of the battery assembly described above; a first battery string and a second battery string arranged adjacent to each other in a first direction, wherein a first solder strip is connected to the first battery string, a second solder strip is connected to the second battery string, and the first battery string and the second battery string are connected in parallel.

[0012] Optionally, the busbar is disposed on the back of the first battery string, and an insulating strip is disposed between the busbar and the first battery string. The insulating strip is located on the side of the first solder strip away from the first battery string, and the insulating strip forms an exposed area through which the first solder strip protrudes. The busbar is electrically connected to the corresponding exposed first solder strip through the exposed area, and the second solder strip extends to the first battery string and connects to the busbar.

[0013] Optionally, the busbar is disposed on the back of the second battery string, and an insulating strip is disposed between the busbar and the second battery string. The insulating strip is located on the side of the first solder strip away from the first battery string, and the insulating strip forms an exposed area through which the second solder strip protrudes. The busbar is electrically connected to the corresponding exposed second solder strip through the exposed area, and the first solder strip extends to the second battery string and connects with the busbar.

[0014] Optionally, the first battery string and the second battery string are spaced apart, and the busbar is disposed between the first battery string and the second battery string.

[0015] Thirdly, a photovoltaic system includes the aforementioned battery module. The technical effects of this application are the same as those of the battery module described above, and will not be repeated here. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the interconnection structure of the first type of battery module provided in the current application; Figure 2 This is a schematic diagram of the interconnection structure of the second type of battery module provided in the current application; Figure 3 This is a schematic diagram of the interconnection structure of the third type of battery module provided in the current application; Figure 4 This is a schematic diagram of the interconnection structure of the third type of battery module provided in the current application.

[0017] Figure 5 This is a structural schematic diagram of the battery assembly provided in the current application; Figure 6 yes Figure 5 An enlarged schematic diagram of the structure at point A.

[0018] Explanation of reference numerals in the attached figures: 100, Busbar; 200, Hollowed-out area; 300, First welding strip; 400, Second welding strip; 600, Bending section; 700, First battery string; 800, Second battery string; 900, Insulating strip. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application. Furthermore, it should be understood that the specific embodiments described herein are merely for explaining this application and are not intended to limit this application.

[0020] In the description of this application, it should be understood that the terms "length", "width", "upper", "lower", "left", "right", "horizontal", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0021] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the stated features. In the description of this application, "a plurality of" means two or more, unless otherwise explicitly specified.

[0022] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0023] In this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature being directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature being directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0024] The following disclosure provides numerous different embodiments or examples for implementing various structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. These are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0025] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown in the embodiment of this application, an interconnection structure for a battery assembly includes a busbar 100 extending along a first direction. The busbar 100 has multiple hollow areas 200 in the first direction. Typically, the busbar 100 is used for current convergence between battery strings within the battery assembly. Conventional busbars are continuous solid structures. In this application, the hollow areas 200 are formed by metal-free openings or through holes designed based on the conventional busbar structure. These hollow areas 200 are typically arranged regularly and at intervals along the length direction of the busbar 100.

[0026] Multiple first solder strips 300 are spaced apart in a first direction and extend along a second direction. Each first solder strip 300 is connected to a busbar 100. That is, the multiple first solder strips 300 are spaced apart along the length of the busbar 100, and each first solder strip 300 is connected to the busbar 100. Multiple second solder strips 400 are spaced apart in the first direction and extend along the second direction. Each second solder strip 400 is connected to the busbar 100. That is, the multiple second solder strips 400 are spaced apart along the length of the busbar 100, and each second solder strip 400 is connected to the busbar 100. It can be understood that the first solder strips 300 and the second solder strips 400... The busbar 100 can be aligned or staggered along its length. At least a portion of at least one of the first solder strip 300 and the second solder strip 400 overlaps with the hollow area 200 of the busbar 100. In other words, at least one of the first solder strip 300 and the second solder strip 400 overlaps with the hollow area 200 of the busbar 100 along its length. This allows the solder strip to slightly sink (partially sink into the hollow area) in the hollow area 200 during welding or lamination, thereby reducing the local stacking height between the solder strip and the busbar 100 and thus reducing the risk of microcracks in the solar cells during the lamination of the photovoltaic module.

[0027] In some embodiments, at least a portion of each of the first solder ribbon 300 and the second solder ribbon 400 is correspondingly overlapped with the cutout area 200 of the busbar 100. That is, both the first solder ribbon 300 and the second solder ribbon 400 are simultaneously arranged corresponding to the cutout area 200 in the length direction of the busbar 100, so that both the first solder ribbon 300 and the second solder ribbon 400 can be partially embedded in the cutout area 200, thereby further reducing the stacking height of the solder ribbons and the busbar 100 after welding, and reducing the risk of microcracks in the solar cells during the lamination process of low-density photovoltaic modules.

[0028] In some embodiments, a plurality of first solder strips 300 and a plurality of second solder strips 400 are staggered in a one-to-one correspondence in a first direction. At least a portion of one of the first solder strips 300 and the second solder strips 400 overlaps with the cutout area 200 of the busbar 100. It can be understood that the other of the first solder strips 300 and the second solder strips 400 is correspondingly staggered with the cutout area 200 of the busbar 100. For example, the first solder strips 300 and the cutout area 200 of the busbar 100 overlap, and the second solder strips 400 and the cutout area 200 are staggered in the length direction of the busbar 100. Alternatively, the second solder strips 400 and the cutout area 200 of the busbar 100 may overlap, and the first solder strips 300 and the cutout area 200 may be staggered in the length direction of the busbar 100. One of the first solder strip 300 and the second solder strip 400 is embedded in the hollow area 200, and the other of the first solder strip 300 and the second solder strip 400 is misaligned with the hollow area 200. This structural design can reduce the local stacking height of the solder strip and the busbar 100. On the other hand, the misalignment design of the first solder strip 300 and the second solder strip 400 can distribute stress more evenly and avoid stress concentration on a certain line, thereby reducing the risk of microcracks in the battery cell.

[0029] In some embodiments, a plurality of first solder strips 300 and a plurality of second solder strips 400 are aligned one-to-one in a first direction, at least a portion of one of the first solder strips 300 and the second solder strips 400 overlaps with the cutout area 200 of the busbar 100, and the other of the first solder strips 300 and the second solder strips 400 has a bent section 600, which is misaligned with the cutout area 200 of the busbar 100. For example, the first welding strip 300 and the hollowed-out area 200 of the busbar 100 are arranged to overlap, and the second welding strip 400 is partially bent and misaligned with the hollowed-out area 200. Alternatively, the second welding strip 400 and the hollowed-out area 200 of the busbar 100 are arranged to overlap, and the first welding strip 300 is partially bent and misaligned with the hollowed-out area 200. This simplifies the arrangement of the welding strips, allowing the first welding strip 300 and the second welding strip 400 to be laid uniformly. Furthermore, it allows for staggered overlapping of the contact portions of the first welding strip 300 and the second welding strip 400 with the busbar 100, thus avoiding stress concentration.

[0030] like Figure 1 , Figure 2 , Figure 3 and Figure 4 As shown, it should be noted that the overlapping arrangement of at least a portion of the first solder strip 300 and / or the second solder strip 400 with the hollow area 200 of the busbar 100 can be either the solder strip being completely embedded in the hollow area 200 or the solder strip being partially embedded in the hollow area 200.

[0031] In some embodiments, the busbar 100 has a through-hole forming a hollow area 200. The through-hole structure ensures that the solder ribbon and busbar 100 are embedded together while maintaining good contact, guaranteeing efficient current collection. Preferably, the ratio of the maximum diameter of the through-hole to the width of the busbar 100 ranges from 10% to 80%. That is, the through-hole can be a regular circular hole or an irregular hole. A ratio of the maximum diameter of the through-hole to the width of the busbar 100 within the above range ensures sufficient conductivity at the contact portion between the solder ribbon and the busbar 100. Further, the width of the solder ribbon is greater than the maximum diameter of the through-hole, allowing the solder ribbon to cover the through-hole and ensuring good electrical contact between the solder ribbon and the busbar. In other embodiments, the width of the solder ribbon can be less than the maximum diameter of the through-hole. In this case, the solder ribbon contacts the un-perforated portion of the busbar, and the portion of the solder ribbon stacked in the through-hole can be completely embedded, reducing the stacking height.

[0032] like Figure 5 and Figure 6 As shown, in some embodiments, a battery assembly includes the interconnection structure of the battery assembly described above; a first battery string 700 and a second battery string 800 are arranged adjacent to each other in a first direction, a first solder strip 300 is connected to the first battery string 700, a second solder strip 400 is connected to the second battery string 800, and the first battery string 700 and the second battery string 800 are connected in parallel. Specifically, one end of the first solder strip 300 is connected to the end of the first battery string 700, one end of the second solder strip 400 is connected to the end of the second battery string 800, and the other ends of the first solder strip 300 and the other ends of the second solder strip 400 are connected together to the busbar 100 to realize the parallel connection of the first battery string 700 and the second battery string 800.

[0033] In some embodiments, the busbar 100 is disposed on the back side of the first battery string 700, and an insulating strip 900 is disposed between the busbar 100 and the first battery string 700. The insulating strip 900 is located on the side of the first solder ribbon 300 facing away from the first battery string 700, and the insulating strip forms an exposed area through which the first solder ribbon 300 is exposed. The busbar 100 is electrically connected to the corresponding exposed first solder ribbon 300 through the exposed area. The second solder ribbon 400 extends to the first battery string 700 and connects with the busbar 100. As a component structure, the busbar 100 is disposed on the back side of the first battery string 700, which can hide the busbar 100 on the back side of the battery string and can reduce or eliminate the gap between the first battery string 700 and the second battery string 800. It is more aesthetically pleasing when viewed from the front of the battery assembly. The insulating strip 900 is required between the busbar 100 and the first battery string 700 to isolate the opposite solder ribbon from the busbar 100 and prevent local short circuits in the battery assembly.

[0034] In some embodiments, the busbar 100 is disposed on the back side of the second battery string 800, and an insulating strip 900 is disposed between the busbar 100 and the second battery string 800. The insulating strip 900 is located on the side of the first solder ribbon 300 facing away from the first battery string 700, and the insulating strip forms an exposed area through which the second solder ribbon 400 is exposed. The busbar 100 is electrically connected to the corresponding exposed second solder ribbon 400 through the exposed area. The first solder ribbon 300 extends to the second battery string 800 and connects with the busbar 100. As a component structure, the busbar 100 is disposed on the back side of the second battery string 800, which can hide the busbar 100 on the back side of the battery string and can reduce or eliminate the gap between the first battery string 700 and the second battery string 800. It is more aesthetically pleasing when viewed from the front of the battery assembly. The insulating strip 900 is required between the busbar 100 and the second battery string 800 to isolate the opposite solder ribbon from the busbar 100 and prevent local short circuits in the battery assembly.

[0035] In some embodiments, the first battery string 700 and the second battery string 800 are spaced apart, and the busbar 100 is disposed between the first battery string 700 and the second battery string 800. Specifically, the first solder strip 300 disposed on the first battery string 700 and the second solder strip 400 disposed on the second battery string 800 each extend to connect with the busbar 100. The busbar 100 is disposed within the interval between the battery strings, thus completely avoiding contact between the busbar 100 and the battery cells during the lamination process, and avoiding the risk of microcracks in the battery cells during the lamination and welding of the solder strips and the busbar 100.

[0036] In some embodiments, a photovoltaic system includes the battery modules as described above. It is understood that the photovoltaic power generation system includes at least one back-contact battery module as described above. It is also understood that the back-contact battery modules can be electrically connected in parallel or in series, depending on actual needs. In this embodiment, the photovoltaic system can be applied in photovoltaic power plants, such as ground-mounted power plants, rooftop power plants, and floating power plants, and can also be applied to equipment or devices that utilize solar energy to generate electricity, such as user solar power supplies, solar streetlights, solar cars, and solar buildings. Of course, it is understood that the application scenarios of the photovoltaic system are not limited to these; that is, the photovoltaic system can be applied in all fields that require solar energy to generate electricity. Taking a photovoltaic power generation system network as an example, the photovoltaic system may include a photovoltaic array, a combiner box, and an inverter. The photovoltaic array can 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.

[0037] In the description of this specification, the references to terms such as "some embodiments," "illustrative embodiments," "examples," "specific examples," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with the described embodiment or example is included in at least one embodiment or example of this application. 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.

[0038] The above description is merely a preferred embodiment of this application and is not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An interconnection structure for a battery assembly, characterized in that, Includes: a busbar extending along a first direction, the busbar having multiple hollow areas in the first direction; A plurality of first solder strips are spaced apart in a first direction and extend along a second direction, each first solder strip being connected to the busbar; A plurality of second solder strips are spaced apart in the first direction and extend along the second direction, each second solder strip being connected to the busbar; at least a portion of at least one of the first solder strips and the second solder strips is correspondingly overlapped with the hollowed-out area of ​​the busbar.

2. The interconnection structure of the battery assembly as described in claim 1, characterized in that, At least a portion of each of the first and second solder strips overlaps with the cutout area of ​​the busbar.

3. The interconnection structure of the battery assembly as described in claim 1, characterized in that, Multiple first solder strips and multiple second solder strips are staggered in a one-to-one correspondence in the first direction, and at least a portion of one of the first solder strips and the second solder strips overlaps with the hollow area of ​​the busbar.

4. The interconnection structure of the battery assembly as described in claim 1, characterized in that, Multiple first solder strips and multiple second solder strips are aligned one-to-one in the first direction. At least a portion of one of the first solder strips and the second solder strips overlaps with the hollow area of ​​the busbar. The other of the first solder strips and the second solder strips has a bent section, and the bent section is staggered with the hollow area of ​​the busbar.

5. The interconnection structure of the battery assembly as described in claim 1, characterized in that, The busbar has through holes that form the hollowed-out area.

6. The interconnection structure of the battery assembly as described in claim 5, characterized in that, The ratio of the maximum diameter of the through hole to the width of the manifold ranges from 10% to 80%.

7. A battery assembly, characterized in that, The battery assembly includes the interconnection structure of any one of claims 1-6; a first battery string and a second battery string arranged adjacent to each other in a first direction, the first solder strip being connected to the first battery string, the second solder strip being connected to the second battery string, and the first battery string and the second battery string being connected in parallel.

8. The battery assembly as claimed in claim 7, characterized in that, The busbar is disposed on the back of the first battery string, and an insulating strip is disposed between the busbar and the first battery string. The insulating strip is located on the side of the first solder strip away from the first battery string, and the insulating strip forms an exposed area through which the first solder strip is exposed. The busbar is electrically connected to the corresponding exposed first solder strip through the exposed area, and the second solder strip extends to the first battery string and connects to the busbar.

9. The battery assembly as claimed in claim 7, characterized in that, The busbar is disposed on the back of the second battery string, and an insulating strip is disposed between the busbar and the second battery string. The insulating strip is located on the side of the first solder strip away from the first battery string, and the insulating strip forms an exposed area through which the second solder strip is exposed. The busbar is electrically connected to the corresponding exposed second solder strip through the exposed area, and the first solder strip extends to the second battery string and connects with the busbar.

10. The battery assembly as claimed in claim 7, characterized in that, The first battery string and the second battery string are spaced apart, and the busbar is disposed between the first battery string and the second battery string.

11. A photovoltaic system, characterized in that, Includes the battery assembly as described in any one of claims 1-10.

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