Conducting bar connecting assembly and battery pack

Abstract

The utility model relates to a conducting bar connecting assembly and a battery pack. The conducting bar connecting assembly comprises a module terminal, a conducting bar, a connecting piece and a locking piece, the module terminal is made of a first material, the conducting bar is made of a second material and is provided with a through hole, and the connecting piece is made of a second material and comprises a first conducting part, a second conducting part and a conducting part connecting the first conducting part and the second conducting part. An accommodating area is formed between the first conductive part and the second conductive part, the conductive bar is inserted in the accommodating area, the conductive bar and the first conductive part form a welding nugget surrounding the through hole on the contact surface, and the side surface, far away from the accommodating area, of the second conductive part is provided with a plating layer made of a first material; the first conductive part and the second conductive part are respectively provided with a first through hole and a second through hole which are coaxial with the through hole, and the locking piece is arranged in the first through hole, the through hole and the second through hole in a penetrating mode, so that the second conductive part abuts against the module terminal through the plating layer. The utility model has the advantages of low cost and long service life.

Description

Technical Field

[0001] This utility model relates to the field of batteries, and in particular to a conductive busbar connection component and a battery pack. Background Technology

[0002] The battery pack of a new energy vehicle consists of multiple battery modules, each with copper terminals. These terminals connect to an aluminum main busbar to establish a circuit. However, due to the potential difference between aluminum and copper, directly connecting the main busbar to the module terminals can lead to corrosion at the connection point, reducing the battery pack's lifespan. Using only copper, on the other hand, results in a heavy and expensive battery pack. One solution is copper-aluminum welding, but this process is cumbersome and cannot guarantee 100% fusion at the copper-aluminum interface. Gaps remain in the un-fused areas, where corrosion can still occur. To avoid these gaps, some manufacturers plate copper in the connection area between the main busbar and the module terminals. However, due to the large size and variable shape of the main busbar, this process is time-consuming and difficult, and still cannot meet actual production needs. Utility Model Content

[0003] Based on this, the purpose of this utility model is to provide a conductive busbar connection component and a battery pack, which have the advantages of low cost and long life.

[0004] A conductive busbar connection assembly includes a module terminal, a conductive busbar, a connector, and a locking member. The module terminal is made of a first material, the conductive busbar is made of a second material and has a through hole, and the connector is made of the second material and includes a first conductive part, a second conductive part, and a conductive part connecting the first conductive part and the second conductive part. A receiving area is formed between the first conductive part and the second conductive part. The conductive busbar is inserted into the receiving area and forms a weld nugget around the through hole on the contact surface with the first conductive part. A plating layer made of the first material is provided on the side of the second conductive part away from the receiving area. A first through hole and a second through hole coaxial with the through hole are respectively opened on the first conductive part and the second conductive part. The locking member passes through the first through hole, the through hole, and the second through hole, so that the second conductive part abuts against the module terminal through the plating layer.

[0005] The conductive busbar connection assembly described in this utility model has a simple structure, which greatly reduces the manufacturing cost of parts. At the same time, it eliminates the electrochemical corrosion caused by potential difference at the connection surface of the connector in humid environments, thus extending the service life of the battery.

[0006] Furthermore, the first material is copper or silver-copper, and the second material is aluminum, which gives the battery good electrical conductivity.

[0007] Furthermore, the connector is made of bent sheet metal, which has a simple structure, is easy to manufacture and assemble, and makes the connection between the connector and the busbar stable.

[0008] Furthermore, the conductive part is arc-shaped or planar, and this structure is compatible with the conductive busbar, making the connector installation stable.

[0009] Furthermore, the thickness of the connector is 0.5 to 1.8 mm, which reduces the weight of the finished product and the manufacturing cost.

[0010] Furthermore, the coating thickness is 5-8 μm. The connector abuts against the module terminal through this coating, thereby avoiding direct contact between copper and aluminum and eliminating the electrochemical corrosion problem caused by potential difference.

[0011] Furthermore, the locking component is a locking screw, the module terminal is provided with a threaded hole, the shaft of the locking screw passes through the first through hole, the through hole and the second through hole in sequence and is threadedly connected to the threaded hole, and its screw head abuts against the first conductive part. Its structure is simple and easy to assemble and disassemble.

[0012] Furthermore, the first conductive portion also has a plating layer formed of a first material on its side away from the receiving area. This structure provides error prevention, avoiding the formation of copper-aluminum contact surfaces due to inverted connectors.

[0013] Furthermore, four welding nuggets are formed between the first conductive part and the conductive busbar, and four welding nuggets are formed between the second conductive part and the conductive busbar, resulting in a stable welding structure.

[0014] A battery pack includes at least two battery modules and a conductive busbar connection assembly as described above. The battery modules are electrically connected to each other through the conductive busbar connection assembly. The battery pack is low in cost, light in weight, and has a long service life.

[0015] To better understand and implement this invention, the following detailed description is provided in conjunction with the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the conductive busbar connection assembly described in this utility model;

[0017] Figure 2 This is a diagram showing the weld nugget distribution between the connector and the busbar.

[0018] Explanation of reference numerals in the attached drawings: 1. Battery module; 2. Module terminal; 21. Threaded hole; 3. Conductive busbar; 31. Through hole; 41. First conductive part; 42. Second conductive part; 43. Conductive part; 44. Receiving area; 45. First through hole; 46. Second through hole; 47. Weld nugget; 48. Plating; 5. Locking element. Detailed Implementation

[0019] Please see Figure 1-2 , Figure 1 This is a cross-sectional view of the conductive busbar connection assembly described in this utility model; Figure 2 This diagram shows the weld nugget distribution of the connector and the busbar. This utility model discloses a battery pack, including at least two battery modules 1 and a busbar connection assembly, wherein the battery modules 1 are electrically connected to each other via the busbar connection assembly.

[0020] The conductive busbar connection assembly includes module terminals 2, conductive busbars 3, connectors, and locking components 5. This assembly enables a stable connection between the first material and the second material. The first and second materials can be of various types, and they have a potential difference. If directly welded, the gaps formed on the weld surface are prone to electrochemical corrosion in humid environments. Currently, new energy battery packs mainly use copper-aluminum connections; therefore, this embodiment describes the first material as copper, silver-copper, or other composite copper, and the second material as aluminum.

[0021] Module terminal 2, made of copper, is mounted on battery module 1 and used for power transmission to battery module 1. Module terminal 2 also has threaded holes 21 for fixed connection. Conductive busbar 3 is typically a long strip structure made of aluminum, serving as a bus to electrically connect to each battery module 1. Conductive busbar 3 is typically 3mm thick, but the actual thickness can be determined depending on the situation; its width is 30-60mm, and its length can be up to approximately 2 meters. Conductive busbar 3 has through holes 31 corresponding to the threaded holes 21.

[0022] The connector is made of bent aluminum sheet, preferably with a thickness of 0.5–1.8 mm. The connector includes a first conductive part 41, a second conductive part 42, and a conductive portion 43. The first conductive part 41 and the second conductive part 42 are spaced apart, with a receiving area 44 between them. The conductive busbar 3 is inserted into the receiving area 44, with the through hole 31 located between the first conductive part 41 and the second conductive part 42. The spacing and shape of the first conductive part 41 and the second conductive part 42 are determined by the thickness and shape of the conductive busbar 3, thus sandwiching the conductive busbar 3 in the middle to facilitate the formation of a weld nugget between the connector and the conductive busbar during subsequent welding.

[0023] The first conductive part 41 and the second conductive part 42 are provided with a coaxial first through hole 45 and a second through hole 46. The locking member 5 can be a pin or other structure. In this embodiment, it is a locking screw. The shaft of the locking screw passes through the first through hole 45, the through hole 31 and the second through hole 46 and is threaded into the threaded hole 21. The screw head abuts against the first conductive part 41, thereby pressing the connector as a whole against the module terminal 2, so that the second conductive part 42 abuts against the module terminal 2, realizing the electrical connection between the connector and the module terminal 2. The first conductive part 41 is also provided with a welding area. After welding, the welding area is fused with the conductive busbar 3 to form a welding nugget 47. Since the connector of this conductive busbar 3 is welded using resistance welding, the welding area is dotted like the electrode. The welding area is distributed around the through hole. In this embodiment, there are four welding areas.

[0024] The connector is also provided with a plating layer 48, the thickness of which is preferably 5-8 μm, and its length and width are equal, both being 50 mm, making the plating layer 48 square, although it can also be circular or other shapes. The connector material is copper or silver-copper, which can be selected according to the surface condition of the battery pack connector. The plating layer 48 covers the surface of the second conductive part 42 away from the receiving area 44, and its area is larger than the contact surface between the module terminal 2 and the second conductive part 42, so that the connector is tightly attached to the module terminal 2 through the plating layer 48, thereby avoiding the formation of an aluminum-copper connection surface and eliminating the electrochemical corrosion problem on the contact surface. In this embodiment, the plating layer 48 can also simultaneously cover the surface of the first conductive part 41 and the second conductive part 42 away from the receiving area 44. In this case, since there is a copper plating layer on both surfaces, it is not necessary to distinguish between the first conductive part 41 and the second conductive part 42 during actual assembly, that is, the first conductive part 41 and the second conductive part 42 can be substituted for each other, thereby avoiding reverse installation. The two ends of the conductive part 43 are respectively connected to the first conductive part 41 and the second conductive part 42 to realize the electrical connection between the first conductive part 41 and the second conductive part 42.

[0025] During assembly, aluminum sheets are first selected according to actual installation requirements and then copper-plated to form a coating 48. Next, the aluminum sheets are cut according to the dimensions of the conductive busbar 3 and the module terminal 2 to obtain appropriately sized aluminum sheets. The aluminum sheets are then bent. In this embodiment, the conductive busbar 3 is a plane with parallel upper and lower sides, so the aluminum sheet is bent into a U-shape, meaning the first conductive part 41 and the second conductive part 42 are parallel and spaced apart. The connecting part 43 electrically connects the first conductive part 41 and the second conductive part 42 through an arc-shaped surface or a flat surface to form a connector.

[0026] Then, the conductive busbar 3 is inserted into the connector, so that the first conductive part 41 and the second conductive part 42 clamp the conductive busbar 3, and the through hole and the through hole 31 are coaxially aligned. At this time, welding is performed by a resistance welding machine, thereby forming four weld nuggets 47 between the first conductive part 41 and the conductive busbar 3, and four weld nuggets 47 between the second conductive part 42 and the conductive busbar 3. Since the contact area between the first conductive part 41, the second conductive part 42 and the conductive busbar 3 is made of aluminum, the welding is actually aluminum-aluminum welding, and the resulting weld is relatively stable.

[0027] Finally, the locking screw is inserted into the through hole 31 and the through hole, and connected to the threaded hole 21, thereby pressing the welded connector and conductive busbar 3 against the module terminal 2. At this time, since the module terminal 2 is made of copper, and the surface of the connector that abuts against the module terminal 2 is plated with a layer 48, this area is copper-copper contact, avoiding corrosion problems caused by the copper-aluminum potential difference and extending the overall service life of the connector.

[0028] The conductive busbar connection assembly and battery pack described in this utility model have a simple structure and stable fusion nugget formation, which greatly reduces the manufacturing cost and welding difficulty of the parts. At the same time, it eliminates electrochemical corrosion caused by potential difference at the joint surface in humid environments, thus extending the battery's service life. In an overcurrent temperature rise test, with a current of 400A for 2 hours and an ambient temperature of 25±3℃, the temperature rise of this conductive busbar connection assembly does not exceed 50℃, meeting the performance requirements.

[0029] In the description of this application, it should be understood that if terms such as "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right" appear, these terms 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.

[0030] Furthermore, where the terms "first" and "second" appear, these terms are 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 with "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, where the term "multiple" appears, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0031] In this application, unless otherwise expressly specified and limited, the terms "installed," "connected," "linked," "fixed," or "set in," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise expressly limited. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0032] The embodiments described above are merely examples of several implementations of this utility model, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the utility model patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this utility model, and this utility model also intends to include these modifications and variations.

Claims

1. A conductive busbar connection assembly, characterized in that: The device includes module terminals, conductive busbars, connectors, and locking components. The module terminals are made of a first material, the conductive busbars are made of a second material and have through holes, and the connectors are also made of a second material. Each connector includes a first conductive portion, a second conductive portion, and a conductive portion connecting the first and second conductive portions. A receiving area is formed between the first and second conductive portions. The conductive busbar is inserted into the receiving area and forms a weld nugget around the through hole on the contact surface with the first conductive portion. The side of the second conductive portion away from the receiving area is provided with a plating layer made of the first material. The first and second conductive portions are respectively provided with a first through hole and a second through hole coaxial with the through hole. The locking component passes through the first through hole, the through hole, and the second through hole, so that the second conductive portion abuts against the module terminals through the plating layer.

2. The conductive busbar connection assembly according to claim 1, characterized in that: The first material is copper or silver-copper, and the second material is aluminum.

3. The conductive busbar connection assembly according to claim 2, characterized in that: The connector is made by bending sheet metal.

4. A conductive busbar connection assembly according to claim 3, characterized in that: The guide portion is either arc-shaped or planar.

5. A conductive busbar connection assembly according to claim 3 or 4, characterized in that: The thickness of the connector is 0.5 to 1.8 mm.

6. A conductive busbar connection assembly according to claim 5, characterized in that: The coating thickness is 5–8 μm.

7. A conductive busbar connection assembly according to claim 2, characterized in that: The locking component is a locking screw. The module terminal is provided with a threaded hole. The shaft of the locking screw passes through the first through hole, the through hole and the second through hole in sequence and is threadedly connected to the threaded hole. The screw head abuts against the first conductive part.

8. A conductive busbar connection assembly according to claim 2, characterized in that: The first conductive part also has a plating layer formed of a first material on the side away from the receiving area.

9. A conductive busbar connection assembly according to claim 2, characterized in that: Four welding nuggets are formed between the first conductive part and the conductive busbar.

10. A battery pack, characterized in that: It includes at least two battery modules and a busbar connection assembly as described in any one of claims 1-9, wherein the battery modules are electrically connected to each other through the busbar connection assembly.

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