Conducting bar processing method, conducting bar and battery pack

Abstract

The invention discloses a processing method of a conducting bar, the conducting bar and a battery pack. The method comprises the following steps: stacking a plurality of conducting strips; and welding the two ends of the plurality of conducting strips, so that first conductive connecting parts are respectively formed at the two ends of the plurality of conducting strips, and the first conductive connecting parts are used for being electrically connected with the battery. When the two first conductive connecting parts generate relative displacement, that is, when the single batteries move relatively, the conductive sheets can generate relative displacement, so that the internal stress of the deformation part of the conductive bar is reduced, and the deformation resistance is reduced, and therefore, the conductive bar provided by the invention has better flexibility.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage equipment, and in particular to a conductive bar processing method, a conductive bar, and a battery pack. Background Art

[0002] Conductive bars are conductive components used to connect the terminals of individual battery cells in a battery pack. Their function is to achieve electrical connectivity between cells. In high-current applications such as power battery packs, conductive bars must possess excellent conductivity, mechanical strength, and the ability to absorb thermal stress to ensure long-term stability and safety. Traditional conductive bars are typically formed from a single piece of aluminum through stamping or machining. Their structural design directly affects the battery pack's resistance to deformation and welding reliability.

[0003] In the prior art, to mitigate deformation of the conductive bar caused by thermal expansion during charging and discharging, a stamped arched structure is commonly used as a buffer design. The local arched shape of this structure provides a certain amount of expansion space, absorbing thermal stress through geometric deformation.

[0004] However, this type of arched structure still has significant defects in practical applications: first, the stamped arched conductive bus is limited by the material hardness and processing technology, and its ductility is limited. In particular, it is easy to lose its buffering capacity due to plastic deformation saturation after multiple thermal cycles; second, the cross-sectional size and shape of the arched area are fixed, which makes it difficult to adapt to stress changes in different directions, resulting in insufficient absorption of lateral thermal stress, which may still cause cracks or even tearing of the conductive bus as a whole; in addition, the stamping process is prone to create sharp edges, further exacerbating the risk of welding heat accumulation and cracks. Summary of the Invention

[0005] One purpose of the present application is to provide a conductive bar processing method, a conductive bar and a battery pack, which are intended to solve the technical problem of insufficient deformation ability of the arched conductive bar in the related art.

[0006] To achieve the above-mentioned objectives, in a first aspect, the present application provides a method for processing a conductive bar, comprising the following steps: stacking a plurality of conductive sheets; welding the two ends of the plurality of conductive sheets to form a first conductive connection portion at both ends of the plurality of conductive sheets, respectively, and the first conductive connection portion is used to electrically connect to a battery.

[0007] In this application, the conductive bar is formed by stacking and welding multiple conductive sheets. The ends of the multiple conductive sheets are welded together to form a first conductive connection portion. Two first conductive connection portions are electrically connected to two battery cells, respectively. The first conductive connection portions are electrically connected to each other via discrete conductive sheets. When the two first conductive connection portions undergo relative displacement, i.e., when the battery cells move relative to each other, the relative displacement of the conductive sheets reduces the internal stress and deformation resistance of the deformed portion of the conductive bar. Therefore, the conductive bar provided in this application has greater flexibility.

[0008] In combination with the first aspect, according to one embodiment of the present application, the method further includes: before welding the two ends of the conductive sheet, sandwiching two gaskets between two adjacent conductive sheets, and the two gaskets are respectively located at the two ends of the conductive sheet for welding the two ends of the adjacent conductive sheets.

[0009] In this embodiment, the stacking arrangement is achieved by sandwiching spacers between adjacent conductive sheets. The spacers participate in the welding process. On the one hand, a stable and reliable first conductive connection can still be formed at both ends of the conductive sheets. On the other hand, the presence of the spacers naturally forms a certain gap between the conductive sheets in the unwelded area in the middle of the conductive sheets. The presence of this gap allows the central portion of the conductive bar to have greater deformation freedom, further releasing the internal stress generated by factors such as battery expansion, vibration, or thermal effects on the conductive bar, significantly improving the flexibility and fatigue resistance of the conductive bar and extending its service life. In addition, this gap can also improve the heat dissipation performance of the conductive bar to a certain extent, facilitating the diffusion and discharge of heat, thereby effectively suppressing the problem of excessive local temperature rise and improving the long-term stability and safety of the conductive bar.

[0010] In combination with the first aspect, according to one embodiment of the present application, the melting point of the conductive sheet is T1, the melting point of the gasket is T2, T1>T2; welding the two ends of multiple conductive sheets includes: heating the conductive sheet and the gasket to a temperature T3 so that the gasket and the conductive sheet are welded and connected, wherein T2<T3<T1.

[0011] In this embodiment, since the melting point T2 of the gasket is lower than the melting point T1 of the conductive sheet, during the welding process of the first conductive connection part, it only needs to be heated to a temperature T3 between T2 and T1 to achieve welding connection, without heating the conductive sheet to its melting point. This effectively avoids the problem of performance degradation or structural changes caused by overheating and melting of the conductive sheet, ensures the original physical and chemical properties of the conductive sheet material, and thus improves the overall conductive reliability and service life of the conductive bus.

[0012] In combination with the first aspect, according to one embodiment of the present application, multiple conductive sheets between the first conductive connection parts form a second conductive connection part, and there are gaps between the parts of adjacent conductive sheets located in the second conductive connection part. The method also includes: disposing or winding a coating layer outside the second conductive connection part, and the coating layer closes all gaps.

[0013] In this embodiment, the coating layer provided outside the second conductive connection seals the gaps between the conductive sheets, trapping the air in the gaps and forming a thermal insulation layer, which reduces the heat dissipation between the sheets. When an abnormal overcurrent occurs in the conductive bar, heat cannot be dissipated promptly, causing the temperature of the second conductive connection to rise rapidly, making it easier to reach the melting point and achieving rapid fuse protection. Thus, this embodiment achieves overheating fuse protection with a simple coating structure, effectively improving the safety and reliability of the conductive bar during use.

[0014] In combination with the first aspect, according to one embodiment of the present application, the plurality of conductive sheets have various thicknesses, and the conductive sheet that is farther from the stack center has a greater thickness.

[0015] In combination with the first aspect, according to one embodiment of the present application, the method further includes: opening a first conductive hole in the area of ​​the conductive sheet corresponding to the first conductive connection portion, and opening a second conductive hole on the gasket, the first conductive hole and the second conductive hole being aligned in the stacking direction of the multiple conductive sheets; providing a conductive column so that the conductive column passes through the first conductive hole and the second conductive hole along the stacking direction of the multiple conductive sheets.

[0016] In combination with the first aspect, according to one embodiment of the present application, the conductive pillar and the first conductive hole have an interference fit; and / or the length of the conductive pillar is selected according to the thickness of the first conductive connecting portion.

[0017] In combination with the first aspect, according to one embodiment of the present application, a plurality of conductive sheets are stacked, including: coating grease on the surface of the conductive sheets, and stacking the plurality of conductive sheets.

[0018] In combination with the first aspect, according to one embodiment of the present application, welding the two ends of the conductive sheet includes: using electromagnetic induction welding and / or ultrasonic welding at the two ends of the conductive sheet.

[0019] In a second aspect, the present application further provides a conductive bar, which is processed using any of the above-mentioned processing methods.

[0020] In a third aspect, the present application further provides a battery pack comprising the above-mentioned conductive bus and single cells, wherein a plurality of single cells are electrically connected via the conductive bus.

[0021] The beneficial effects of the second and third aspects can be referred to the first aspect or any possible implementation of the first aspect, and will not be described in detail here. Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations.

[0022] Other advantages, objectives and features of the present application will be reflected in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0024] Figure 1 This is one of the flow charts of the conductive bar processing method provided in the embodiment of the present application;

[0025] Figure 2 This is a schematic diagram of the overall structure of the conductive bar provided in an embodiment of the present application;

[0026] Figure 3 yes Figure 1 A partial enlarged view of area A in the middle;

[0027] Figure 4 This is a schematic diagram of the overall structure of a conductive bar provided by another embodiment of the present application;

[0028] Figure 5 It is along Figure 4 Schematic cross-section of the middle BB line;

[0029] Figure 6 yes Figure 5 A partial enlarged view of the middle C area;

[0030] Figure 7 1 is a schematic diagram of the assembly process of the conductive column provided in an embodiment of the present application;

[0031] Figure 8 This is the second flow chart of the conductive bar processing method provided in the embodiment of the present application.

[0032] Description of Figure Numbers:

[0033] 1. First conductive connection part; 2. Second conductive connection part; 3. Conductive sheet; 4. Gasket; 5. Covering layer; 6. Conductive column; 7. Grease. DETAILED DESCRIPTION

[0034] The following will be combined with the drawings in the embodiments of this application to clearly and completely describe the technical solutions in the embodiments of this application. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0035] The conductive busbar is a conductive component that connects the battery terminals in a battery pack and provides the electrical connection between individual cells. To ensure output stability and safety, the busbar must possess excellent conductivity, mechanical strength, and thermal stress absorption. Traditionally, the busbar is formed by stamping or machining, and its structural design affects the battery pack's resistance to deformation and welding reliability. To mitigate deformation caused by thermal expansion of the busbar, a common design uses a stamped arched structure as a buffer at the connection, providing space to absorb the stress generated by the expansion of the individual cells.

[0036] However, the aforementioned arched structure formed by stamping has numerous drawbacks. For example, its ductility is limited by the material composition and processing technology, significantly degrading its buffering capacity after multiple thermal cycles. Its fixed cross-sectional size and shape make it difficult to adapt to stress variations in different directions. The stamping process also creates sharp edges, exacerbating the risk of weld heat accumulation and cracking. Therefore, a new conductive busbar processing technology is needed to address the technical issues of insufficient deformability of arched conductive busbars in related technologies.

[0037] In order to solve the above technical problems, firstly, referring to Figures 1 to 3 As shown, the present application provides a method for processing a conductive bar, comprising the following steps:

[0038] S101: stacking a plurality of conductive sheets 3; the conductive sheets 3 are exemplarily made of aluminum sheets and exemplarily shaped as rectangular sheets.

[0039] S103: welding two ends of a plurality of conductive sheets 3 to form first conductive connection parts 1 at both ends of the conductive sheets 3 , respectively. The first conductive connection parts 1 are used for electrically connecting to the battery.

[0040] Here, welding the two ends of multiple conductive sheets 3 should be understood as the molten pool formed by welding penetrating all the conductive sheets 3, or the molten pool is dispersed throughout the entire first conductive connection part 1 in the stacking direction of the conductive sheets 3, so that all the conductive sheets 3 form a complete first conductive connection part 1 at both ends of the conductive bar. The specific welding process is exemplified by using electromagnetic induction welding and / or ultrasonic welding at both ends of the conductive sheet 3 to achieve a reliable welding structure that penetrates the first conductive connection part 1. The electrical connection between the conductive bar and the battery is exemplified by: the first conductive connection part 1 is welded to the battery pole, or, after the first conductive connection part 1 abuts against the battery electrode, the relative position of the two is fixed by a clamp.

[0041] This application stacks multiple conductive sheets 3 and welds them together at both ends, creating a discrete sheet structure in the middle region. Each sheet 3 can deform and displace relatively independently, effectively improving the flexibility of the conductive bar. When displacement or vibration occurs between battery cells, the conductive bar can effectively avoid the accumulation of internal stress through relative sliding between the sheets, significantly reducing deformation resistance within the conductive bar and avoiding the risk of fatigue fracture in integrally stamped conductive bars. This improves the reliability and safety of the conductive bar in complex operating conditions.

[0042] Furthermore, with current machining precision, it is often difficult to precisely machine the tiny gaps between the conductive sheets 3 within the conductive bar using subtractive manufacturing. While additive manufacturing is feasible, it suffers from high costs and low efficiency. This embodiment, by stacking the conductive sheets 3 and then welding their ends together, naturally creates gaps between them. This avoids the stringent machining precision requirements of complex processes and eliminates the need for expensive additive manufacturing equipment. This reduces the cost and difficulty of the process, improves production efficiency and affordability, and offers significant process and economic advantages over existing manufacturing techniques.

[0043] In one embodiment of the present application, before welding the two ends of the plurality of conductive sheets 3, the method further comprises:

[0044] Two gaskets 4 are sandwiched between two adjacent conductive sheets 3 . The two gaskets 4 are respectively located at two ends of the conductive sheet 3 for welding the two ends of the adjacent conductive sheets 3 .

[0045] It should be noted that, from the perspective of processing technology, the operation of sandwiching a gasket 4 between two adjacent conductive sheets 3 can be to first stack multiple conductive sheets 3 and then insert the gasket 4 between the adjacent conductive sheets 3; or, the conductive sheets 3 and gaskets 4 can be placed alternately layer by layer to realize the sandwich structure of the gasket 4.

[0046] In this embodiment, two gaskets 4 are sandwiched between adjacent conductive sheets 3 to form a stack. The two gaskets 4 are respectively located at two ends of the conductive sheet 3 and participate in the welding process of the first conductive connection portion 1 .

[0047] In terms of structural function, the provision of the gasket 4 enables stable and reliable welding connection with the conductive sheet 3 in the welding areas at both ends of the conductive bar, ensuring the formation of a first conductive connection portion 1 with stable mechanical strength and electrical performance in the welding area; and in the unwelded area in the middle section of the conductive sheet 3, due to the presence of the gasket 4, a certain gap is naturally generated between the conductive sheets 3, so that the conductive sheets 3 can slide relative to each other more freely during the displacement process caused by the expansion, vibration or thermal effect of the battery cell, thereby fully releasing the internal stress and effectively improving the flexibility of the conductive bar.

[0048] From a manufacturing perspective, by placing spacers 4 between the conductive sheets 3 and employing a welding process, gaps between the conductive sheets 3 can be naturally formed. Compared to a solution without spacers 4, this embodiment does not change the production process steps, allowing the new conductive bar structure to be processed on existing production lines, maintaining the process economic advantages of this application over existing processing methods.

[0049] It should be understood that under most operating conditions, the gaps formed between adjacent conductive sheets 3 allow airflow to pass through, so that convective heat transfer, which was originally limited to the surface of the conductive bar, is widely present on the surface of each conductive sheet 3, significantly increasing the heat dissipation area and heat dissipation efficiency, which is beneficial to controlling the operating temperature of the conductive bar.

[0050] In other technical solutions, please refer to Figures 5 to 7 As shown, multiple conductive sheets 3 between the first conductive connection parts 1 form a second conductive connection part 2, and there are gaps between the parts of adjacent conductive sheets 3 located in the second conductive connection part 2. The method also includes: disposing or winding a coating layer 5 outside the second conductive connection part 2, and the coating layer closes all gaps.

[0051] In this embodiment, by providing or wrapping a coating 5 around the second conductive connection portion 2, the coating 5 completely seals the gaps between the conductive sheets 3, trapping the air in the gaps to form a thermal insulation layer. The low thermal conductivity of air significantly reduces the efficiency of heat conduction between the conductive sheets 3 in the second conductive connection portion 2, as well as between the conductive sheets 3 and the outside world. If an abnormal current overload or short circuit occurs in the conductive bar, the generated heat cannot be dissipated promptly, causing the temperature of the conductive sheets 3 in the second conductive connection portion 2 to rise rapidly, reaching the melting temperature of the conductive sheets 3 or the connection portion more quickly, thereby achieving rapid fuse protection.

[0052] It's important to note that in addition to the fuse's effectiveness, in this embodiment, due to the presence of a thermal insulation layer within the second conductive connection portion 2, the conductive bar's fusing occurs directional within the second conductive connection portion 2. This ensures that during the conductive bar's fusing process, the batteries electrically connected to the first conductive connection portion 1, particularly the battery terminals, are generally preserved. This prevents battery burnout from system overloads and avoids increased repair costs caused by terminal melting during non-directional fusing.

[0053] It should be understood that the material and shape of the gasket 4 can be flexibly selected according to actual production conditions. According to one embodiment of the present application, the melting point of the conductive sheet 3 is T1, and the melting point of the gasket 4 is T2, T1>T2; welding the two ends of the conductive sheet 3 includes: heating the conductive sheet 3 and the gasket 4 to a temperature of T3, so that the gasket 4 is welded to the conductive sheet 3, wherein T2<T3<T1.

[0054] Welding is a process in which at least a portion of the parent material or solder is heated to melt and then resolidified to achieve atomic-level bonding. If the conductive sheet 3 is heated to its melting point or above, melting can cause grain coarsening, weakened grain boundaries, and uneven microstructural changes in the sheet 3, seriously affecting its electrical conductivity, mechanical strength, and fatigue resistance. This is one reason why the welds between the conductive bar and the battery post are prone to tearing when the battery expands. Furthermore, the melting and resolidification of the conductive sheet 3 often generates significant residual internal stress, which can easily induce stress concentration and fatigue cracks in the weld area, reducing the reliability and service life of the conductive bar under complex operating conditions such as long-term vibration, thermal expansion, and cyclic loading.

[0055] In this embodiment, because the melting point T2 of the gasket 4 is lower than the melting point T1 of the conductive sheet 3, the first conductive connection portion 1 only needs to be heated to a temperature T3 during the welding process to achieve a welded connection, without having to heat the conductive sheet 3 to its melting point. Controlling the welding process in this embodiment prevents overheating and melting of the conductive sheet 3, effectively preserving the original microstructure and physical and chemical properties of the conductive sheet 3 material, and significantly improving the stability and conductivity of the conductive bar's overall structure.

[0056] Similarly, the thickness of the conductive sheet 3 can also be selected based on actual conditions. Different conductive sheets 3 can have the same or different thicknesses, and different regions of the same conductive sheet 3 can also have different thicknesses based on different design configurations. According to one embodiment of the present application, the conductive sheet 3 has multiple thicknesses, and the conductive sheet 3 farther from the center of the stack has a greater thickness.

[0057] In this embodiment, the thickness of the conductive sheets 3 increases as they move away from the center of the stack. The outer conductive sheets 3 have better heat dissipation and are therefore thicker, while the inner conductive sheets 3 have poorer heat dissipation and are therefore thinner. During normal current carrying, the overall conductive area is unaffected, and normal current carrying capacity is not reduced. However, when an abnormal situation occurs and a fuse is required, the inner conductive sheets 3, which are thinner and have poorer heat dissipation, are more likely to overheat and fuse. Once the inner conductive sheet 3 fuses, the current carrying density of the remaining unfused conductive sheets 3 increases rapidly, causing these conductive sheets 3 to quickly reach the melting temperature, thereby achieving rapid fuse-fusing of the entire conductive stack and providing better protection.

[0058] Reference Figures 4 to 7 As shown, according to one embodiment of the present application, the method further includes:

[0059] S701: Opening a first conductive hole in a region of the conductive sheet 3 corresponding to the first conductive connecting portion 1 , and opening a second conductive hole in the gasket 4 , wherein the first conductive hole and the second conductive hole are aligned in the stacking direction of the plurality of conductive sheets 3 ;

[0060] The first and second conductive vias referred to in this embodiment should be understood as holes through which the conductive pillars 6 pass. In practice, as long as the walls of the first conductive vias can carry current, the conductive pillars 6 can function as conductors. The walls of the second conductive vias, or even the gasket 4, do not need to be conductive in this embodiment. The shapes of the first and second conductive vias are, for example, cylindrical or prismatic.

[0061] S703 : providing a conductive column 6 , and allowing the conductive column 6 to penetrate a plurality of first conductive holes and a second conductive hole along the stacking direction of the plurality of conductive sheets 3 .

[0062] The conductive pillar 6 is exemplarily shaped as a cylinder or a prism.

[0063] On the one hand, the provision of the conductive column 6 adds an additional conductive path between the multiple conductive sheets 3. Even if the gasket 4 itself is non-conductive or has poor conductivity, reliable current transmission can be achieved through the conductive column 6, avoiding the decline in overall conductivity due to the high resistivity of the gasket 4. Accordingly, the presence of the conductive column 6 also reduces the requirements for the conductive properties of the gasket 4 material, expands the range of choices for the gasket 4 material, so as to adapt to more functions other than conductivity. On the other hand, the conductive column 6 also plays a role in mechanical fixation. Even if the connection between the conductive sheet 3 and the gasket 4 becomes loose or detached due to external force or thermal expansion, the conductive column 6 can still fix the position of the conductive sheet 3, prevent the first conductive connection part 1 from falling apart or structural failure, and enhance the stability of the mechanical structure and safety of use.

[0064] It should be noted that the relevant processing steps of the conductive pillar 6 disclosed in this embodiment can be set before the welding of step S103, or can be set after the welding of step S103.

[0065] Specifically, the conductive pillar 6 forms an interference fit with the first conductive hole to enhance the structural stability of the first conductive connection part 1 and further reduce the functional requirements of the gasket 4. The length of the conductive pillar 6 is selected based on the thickness of the first conductive connection part 1. For example, the length of the conductive pillar 6 is the same as the thickness of the first conductive connection part 1. That is, the length of the conductive pillar 6 is equal to the sum of the thicknesses of the conductive sheet 3 plus the sum of the thicknesses of all gaskets 4 in a conductive connection part. This allows the first conductive connection part 1 to maintain a complete surface appearance, facilitating the design of the assembly structure.

[0066] refer to Figures 4 to 6 ,as well as Figure 8 In another embodiment of the present application, a plurality of conductive sheets 3 are stacked and arranged, including:

[0067] S801: Apply lubricating grease 7 on the surface of the conductive sheet 3;

[0068] S803: stacking a plurality of conductive sheets 3.

[0069] The processing method of this embodiment effectively improves the contact between the conductive sheets 3 by coating the surfaces of the conductive sheets 3 with grease 7 before stacking the sheets. On the one hand, the presence of grease 7 fills and seals the tiny gaps between the conductive sheets 3, isolating them from air and moisture, effectively inhibiting oxidation or corrosion on the surfaces of the conductive sheets 3 and ensuring long-term, stable electrical connection performance. On the other hand, the lubricating effect of grease 7 also reduces mechanical wear during the stacking of the conductive sheets 3, lowering friction at the contact interface, further enhancing the flexibility of the conductive bars and extending their service life.

[0070] Exemplarily, the grease 7 is conductive silicone grease, which enhances the flexibility of the second conductive connection part 2 while making the second conductive connection part 2 have better current carrying capacity, especially when a local conductive sheet 3 is broken, the current carrying capacity of the entire conductive row is basically unaffected.

[0071] In a second aspect, the present application further provides a conductive bar, which is processed using any of the above-mentioned processing methods.

[0072] In a third aspect, the present application further provides a battery pack comprising the above-mentioned conductive bus and single cells, wherein a plurality of single cells are electrically connected via the conductive bus.

[0073] Because the conductive bar is manufactured using the above-mentioned processing method and the battery pack includes the above-mentioned conductive bar, the conductive bar also has the above-mentioned technical effects. The beneficial effects of the second and third aspects can be referred to the first aspect or any possible implementation of the first aspect, and are not described in detail here. Based on the implementations provided in the above aspects, this application can also be further combined to provide more implementations.

[0074] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship and movement status between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0075] It should also be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it may be directly on the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it may be directly connected to the other element or indirectly connected to the other element through an intervening element.

[0076] In addition, the descriptions of "first", "second", etc. in this application are for descriptive purposes only and should not be understood as indicating or implying their relative importance or implicitly indicating the number of the technical features indicated. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of such features. In addition, the technical solutions between the various embodiments can be combined with each other, but this must be based on the fact that they can be implemented by ordinary technicians in this field. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0077] The above description is only a preferred embodiment of the present application and does not limit the patent scope of the present application. All equivalent structural transformations made based on the design concept of the present application and the contents of the present application description and drawings, or direct / indirect application in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A method for processing a conductive bar, characterized in that: The following steps are involved: stacking a plurality of conductive sheets; The two ends of the plurality of conductive sheets are welded to form first conductive connection portions at the two ends of the plurality of conductive sheets, respectively. The first conductive connection portions are used to electrically connect to a battery.

2. The method for processing a conductive bar according to claim 1, wherein: The method further includes: before welding the two ends of the plurality of conductive sheets, sandwiching two gaskets between two adjacent conductive sheets, wherein the two gaskets are respectively located at the two ends of the conductive sheets for welding the two ends of the adjacent conductive sheets.

3. The method for processing a conductive bar according to claim 2, wherein: The melting point of the conductive sheet is T1, the melting point of the gasket is T2, and T1>T2; The welding of the two ends of the plurality of conductive sheets includes: heating the conductive sheets and the gaskets to a temperature T3 so that the gaskets and the conductive sheets are welded together, wherein T2<T3<T1.

4. The method for processing a conductive bar according to claim 2, wherein: The plurality of conductive sheets between the first conductive connecting portions form a second conductive connecting portion, and gaps exist between portions of adjacent conductive sheets located in the second conductive connecting portion. The method further includes: A covering layer is disposed on or around the second conductive connection portion, and the covering layer closes all the gaps.

5. The method for processing a conductive bar according to claim 4, wherein: The plurality of conductive sheets have various thicknesses, and the conductive sheets farther from the stacking center have greater thicknesses.

6. The method for processing a conductive bar according to claim 2, wherein: The method further includes: A first conductive hole is formed in a region of the conductive sheet corresponding to the first conductive connection portion, and a second conductive hole is formed on the gasket, wherein the first conductive hole and the second conductive hole are aligned in the stacking direction of the plurality of conductive sheets; A conductive column is provided, and the conductive column is made to penetrate the first conductive hole and the second conductive hole along the stacking direction of the plurality of conductive sheets.

7. The method for processing a conductive bar according to claim 6, wherein: The conductive pillar and the first conductive hole are interference-fitted; and / or The length of the conductive pillar is selected according to the thickness of the first conductive connecting portion.

8. The method for processing a conductive bar according to claim 1, wherein: The stacking of the plurality of conductive sheets comprises: coating grease on the surfaces of the conductive sheets, and stacking the plurality of conductive sheets.

9. The method for processing a conductive bar according to any one of claims 1 to 8, characterized in that: The welding of the two ends of the conductive sheet includes: using electromagnetic induction welding and / or ultrasonic welding on the two ends of the conductive sheet.

10. A conductive bar, characterized in that: The method is obtained by processing using any one of claims 1 to 9.

11. A battery pack, characterized in that: include: The conductive bar according to claim 10; Single battery, multiple single batteries are electrically connected through the conductive bus.

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