Flexible connecting bar and battery pack

Abstract

The utility model discloses a flexible connecting bar and battery pack, the flexible connecting bar includes conductive member and riveting member, the conductive member includes a plurality of conductive foils, the plurality of conductive foils are laminated along its thickness direction, the conductive member is provided with a plurality of fixing holes that pass through the plurality of conductive foils in order; and the riveting piece penetrates through the fixing hole and is riveted and fixed with the conductive piece. According to the riveting piece, a plurality of conductive foils are connected together in a riveting mode, and the connection strength is high. The conductive part has flexibility, can provide a buffer space, and prevents the riveting part from being separated from the pole post after being pulled, thereby preventing electrical connection from being disconnected. And the riveting parts made of different materials can be replaced according to the requirements of conductivity and welding strength.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a flexible connecting strip and battery pack. Background Technology

[0002] When the system places higher demands on the current carrying capacity of the cell-to-cell connector and the width of the connector cannot be increased due to creepage distance limitations, increasing the thickness of the connector becomes the only option. However, increasing the thickness of the connector will prevent it from effectively absorbing the displacement caused by the expansion force of the battery during use, increasing the risk of deformation or pull-out of the connector and terminals. Utility Model Content

[0003] One objective of this invention is to provide a flexible connector and battery pack, which aims to solve the technical problem of connector pull-out from terminal posts.

[0004] To achieve the above objectives, the present invention provides a solution as follows: a flexible connecting strip, the flexible connecting strip including a conductive element and a riveting element, the conductive element including multiple conductive foils, the multiple conductive foils being stacked along their thickness direction, the conductive element having fixing holes that sequentially penetrate the multiple conductive foils; the riveting element passing through the fixing holes and riveting and fixing to the conductive element.

[0005] Optionally, the thickness of the conductive foil is D1 mm, where 0.05 ≤ D1 ≤ 0.3.

[0006] Optionally, the thickness of the conductive element is D2 mm, where 2 ≤ D2 ≤ 4.

[0007] Optionally, the riveting component includes a first substrate, a connecting plate, and a second substrate. The two opposite ends of the connecting plate are respectively connected to the first substrate and the second substrate. The connecting plate passes through the fixing hole, and the first substrate and the second substrate together clamp the conductive component.

[0008] Optionally, the first substrate and the connecting plate are arranged to form a welding groove, and the first substrate is used for electrical connection with the pole post.

[0009] Optionally, the first substrate has a positioning hole along its thickness direction, and the positioning hole is connected to the welding groove.

[0010] Optionally, the width of the first substrate is L1, and the diameter of the fixing hole is R, where 0.4 ≤ R / L1 ≤ 0.7.

[0011] Optionally, the width of the first substrate is L1, and the width of the second substrate is L2, where 0.4 ≤ L2 / L1 ≤ 0.9.

[0012] Optionally, the diameter of the positioning hole is R1, and the diameter of the fixing hole is R, where 0.2≤R1 / R≤0.4.

[0013] Optionally, the conductive foil includes an electrical portion and a buffer portion. The electrical portion is provided at opposite ends of the buffer portion. The buffer portion protrudes along its thickness direction to form a buffer groove. Multiple electrical portions are stacked along their thickness direction, and multiple buffer portions are stacked along their thickness direction. The fixing hole passes through multiple electrical portions in sequence.

[0014] To achieve the above objectives, the present invention provides a solution as follows: a battery pack comprising: a plurality of individual cells and a flexible connecting bar as described in any of the above claims, wherein the flexible connecting bar is electrically connected to the terminals of adjacent individual cells.

[0015] The beneficial effects of this utility model are as follows:

[0016] A single conductive foil is flexible and can deform under external force. Multiple conductive foils stacked together form a conductive element of a certain thickness, possessing both structural strength and flexibility. When adjacent cells deform and their terminals move away from each other, the rivet and conductive element connect, and the rivet and terminal are also connected. The conductive element provides a buffer space for the flexible connector, preventing the rivet from being pulled away from the terminal and breaking the electrical connection. Compared to a rigid connector, the flexible connector of this application has better bending and deformation performance. During use, it can better absorb displacement caused by module expansion force, reducing the risk of terminal deformation. The current carrying capacity of the flexible connector can be adjusted by changing the number of conductive foils. Compared to a single rigid connector, the flexible connector has small gaps between its multiple conductive foils, increasing the contact area between the aluminum busbar and the air, which is more conducive to heat dissipation.

[0017] Furthermore, the riveting components can be freely switched between different conductive materials such as aluminum or copper and welded to the terminals, thus the materials of the positive and negative terminals are not limited by the material of the connector. For example, if a riveting component with good conductivity is required, it can be made of copper; if high weld strength is required, the riveting component and the terminal can be made of the same material. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the assembly structure of the battery pack provided by this utility model;

[0020] Figure 2 This is a schematic diagram of the structure of the flexible connecting strip provided by this utility model;

[0021] Figure 3 This is a schematic diagram of the structure of the conductive component provided by this utility model;

[0022] Figure 4 This is a schematic diagram of the cross-sectional structure of the flexible connecting strip provided by this utility model;

[0023] Figure 5 This utility model provides Figure 4 A magnified view of a portion of region A in the middle.

[0024] Reference numerals: 10 flexible connecting strip, 12 conductive component, 121 conductive foil, 123 electrical component;

[0025] Buffer part 124, fixing hole 125, riveting part 14, first base plate 141, positioning hole 145;

[0026] Connecting plate 142, second substrate 143, welding groove 140;

[0027] Single cell 00. Detailed Implementation

[0028] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0029] Please see Figures 1 to 3 As shown, Figure 1 This is a schematic diagram of the assembly structure of the battery pack provided by this utility model. Figure 2 This is a structural schematic diagram of the flexible connecting row 10 provided by this utility model. Figure 3 This is a schematic diagram of the structure of the conductive component 12 provided by this utility model.

[0030] This utility model provides a battery pack, which includes multiple individual cells 00 and a flexible connection bar 10. The flexible connection bar 10 is electrically connected to the terminals of adjacent individual cells 00 to electrically connect adjacent individual cells 00 together. The flexible connection bar 10 can connect adjacent individual cells 00 in series or in parallel.

[0031] The flexible connecting strip 10 includes a conductive element 12 and a riveting element 14. The conductive element 12 includes multiple conductive foils 121, which are stacked along their thickness direction and electrically connected to adjacent conductive foils 121. The conductive element 12 has fixing holes 125 that sequentially pass through the multiple conductive foils 121. Each conductive foil 121 has sub-holes, which are interconnected to form the fixing holes 125. The riveting element 14 passes through the fixing holes 125 and is riveted to the conductive element 12 for fixation. Riveting (also known as rivet connection) is a mechanical term referring to a method of connecting multiple parts by using axial force to thicken the rivet shank within the rivet hole and form a rivet head. Riveting results in smaller gaps between connected parts, preventing water or dust ingress, and also provides high connection strength.

[0032] In this embodiment, a single conductive foil 121 is in a flexible state and can deform under external force. Multiple conductive foils 121 are stacked together to form a conductive element 12 of a certain thickness. At this time, the conductive element 12 has both structural strength and flexibility. When adjacent single cells 00 deform and the terminals on adjacent single cells 00 move away from each other, the rivet 14 and the conductive element 12 are connected, and the rivet 14 is connected to the terminal. The conductive element 12 can provide a certain buffer space for the flexible connection row 10 to prevent the rivet 14 from being pulled away from the terminal and breaking the electrical connection.

[0033] Compared to rigid connectors, the flexible connector 10 of this application has better bending and deformation performance. During use, it can better absorb the displacement caused by module expansion force, reducing the risk of deformation of the electrode post. The current carrying capacity of the flexible connector 10 can be adjusted by changing the number of conductive foils 121. Compared to a single rigid connector, the flexible connector 10 has small gaps between the multiple conductive foils, increasing the contact area between the aluminum busbar and the air, which is more conducive to heat dissipation of the connector.

[0034] Furthermore, the crimping component 14 can be freely switched to different conductive materials such as aluminum or copper and welded to the terminal post, so that the materials of the positive and negative terminals are not limited by the material of the connector. For example, if a crimping component 14 with good conductivity is required, then the crimping component 14 made of copper can be replaced; if high welding strength is required, then the crimping component 14 and the terminal post can be made of the same material.

[0035] Please see Figures 1 to 5 As shown, Figure 4 This is a schematic diagram of the cross-sectional structure of the flexible connecting row 10 provided by this utility model. Figure 5 This utility model provides Figure 4 A magnified view of a portion of region A in the middle.

[0036] The thickness of the conductive foil 121 is D1 mm, where 0.05 ≤ D1 ≤ 0.3, and further, 0.1 ≤ D1 ≤ 0.2. D1 can be 0.05, 0.08, 0.1, 0.12, 0.15, 0.18, 0.2, 0.25, 0.28, 0.3, etc. Within this range, the conductive foil 121 has relatively high flexibility and can deform normally under external force. When the thickness exceeds this range, the conductive foil 121 has weak flexibility and cannot deform promptly or normally under external force. When the thickness of the conductive foil 121 is less than this range, it is prone to breakage under stress, thus increasing the manufacturing difficulty and cost of the conductive component 12.

[0037] The thickness of the conductive element 12 is D2 mm, where 2 ≤ D2 ≤ 4, and further, 2.5 ≤ D2 ≤ 3.5. D2 can be 2, 2.1, 2.3, 2.5, 2.6, 2.8, 3.0, 3.2, 3.5, 3.6, 3.8, 4.0, etc. Within this range, the conductive element 12 has relatively high flexibility and can deform normally under external force. When it exceeds this range, the conductive element 12 has weak flexibility and cannot deform promptly or normally under external force. When the conductive element 12 is smaller than this range, the conductive foil 121 is prone to breakage under stress, thus increasing the manufacturing difficulty and cost of the conductive element 12.

[0038] The conductive foil 121 can be made of copper, aluminum, copper, or their alloys. The riveting component 14 can be made of copper, aluminum, copper, or their alloys.

[0039] The riveting component 14 includes a first substrate 141, a connecting plate 142, and a second substrate 143. The two opposite ends of the connecting plate 142 are connected to the first substrate 141 and the second substrate 143, respectively. The connecting plate 142 has a fixing hole 125. The first substrate 141 and the second substrate 143 together clamp the conductive component 12. The first substrate 141 is electrically connected to the conductive foil 121 located at the starting position, and the second substrate 143 is electrically connected to the conductive foil 121 located at the ending position. Then, they are sequentially pressed along the thickness direction of the conductive component 12, thereby connecting multiple conductive foils 121 together. At this time, the first substrate 141 can be electrically connected to the electrode post, or the second substrate 143 can be electrically connected to the electrode post.

[0040] In this embodiment, the first substrate 141 and the second substrate 143 are formed during the riveting process and flatly attached to the conductive foil 121. The first substrate 141 and the second substrate 143 press together multiple conductive foils 121, making the multiple conductive foils 121 tightly connected together. The first substrate 141 or the second substrate 143 can also be welded to the electrode post to achieve electrical connection. The welding method can be laser welding or friction welding.

[0041] Optionally, taking the electrical connection between the first substrate 141 and the electrode post as an example, the first substrate 141 and the connecting plate 142 form a welding groove 140, and the first substrate 141 is used for electrical connection with the electrode post. It can be understood that the welding groove 140 passes through the connecting plate 142 and the second substrate 143, and can directly contact the first substrate 141 through the welding groove 140. The welder passes through the welding groove 140 and directly contacts the first substrate 141, injecting heat into the first substrate 141, so that the first substrate 141 and the electrode post are welded together.

[0042] By forming a welding groove 140 on the riveting part 14, the thickness of the riveting part 14 is locally reduced, thereby facilitating heat transfer and making it easier for the first substrate 141 to be welded to the pole post under the action of a low-power welder. This not only reduces the power of the welder but also increases the connection strength between the first substrate 141 and the pole post. In addition, the welding groove 140 also serves to contain and shield sparks generated during the welding process, preventing molten slag from splashing and burning other components.

[0043] The first substrate 141 has a positioning hole 145 along its thickness direction. The positioning hole 145 penetrates the first substrate 141 and is connected to the welding groove 140. The positioning hole 145 can be circular, square, or triangular. During the welding process, the positioning hole 145 can be aligned with the center of the electrode post. At this time, the contact area between the first substrate 141 and the electrode post is maximized, and the first substrate 141 can also evenly transfer heat to the radial direction of the electrode post, thereby maximizing the connection strength between the first substrate 141 and the electrode post.

[0044] The width of the first substrate 141 is L1, and the diameter of the fixing hole 125 is R, where 0.4 ≤ R / L1 ≤ 0.7, and further, 0.5 ≤ R / L1 ≤ 0.6. R / L1 can be 0.4, 0.42, 0.45, 0.5, 0.52, 0.55, 0.58, 0.6, 0.62, 0.64, 0.68, 0.7, etc.

[0045] Within this range, the first substrate 141 can clamp multiple conductive foils 121 with the second substrate 143 without detaching, and the first substrate 141 can also be securely welded to the electrode post. When the size exceeds this range, the first substrate 141 becomes too small, and the multiple conductive foils 121 clamped by the first substrate 141 and the second substrate 143 are prone to detachment. Furthermore, the contact area between the first substrate 141 and the electrode post is too small, resulting in insufficient connection strength. When the conductive element 12 is smaller than this range, the clamping strength of the first substrate 141 and the second substrate 143 on the multiple conductive foils 121 does not increase, nor does the connection strength between the first substrate 141 and the electrode post; instead, it increases the production cost of the crimping element 14.

[0046] The width of the first substrate 141 is L1, and the width of the second substrate 143 is L2, where 0.4 ≤ L2 / L1 ≤ 0.9. Further, 0.5 ≤ L2 / L1 ≤ 0.7. L2 / L1 can be 0.4, 0.42, 0.45, 0.5, 0.55, 0.6, 0.65, 0.7, 0.75, 0.8, 0.85, 0.9, etc.

[0047] Within this range, the first substrate 141 can clamp multiple conductive foils 121 with the second substrate 143 without detaching, and the first substrate 141 can also be securely welded to the electrode post. When the size exceeds this range, the first substrate 141 becomes too small, and the multiple conductive foils 121 clamped by the first substrate 141 and the second substrate 143 are prone to detachment. Furthermore, the contact area between the first substrate 141 and the electrode post is too small, resulting in insufficient connection strength. When the conductive element 12 is smaller than this range, the clamping strength of the first substrate 141 and the second substrate 143 on the multiple conductive foils 121 does not increase, nor does the connection strength between the first substrate 141 and the electrode post; instead, it increases the production cost of the crimping element 14.

[0048] The diameter of the positioning hole 145 is R1, and the diameter of the fixing hole 125 is R, where 0.2 ≤ R1 / R ≤ 0.4. Further, 0.25 ≤ R1 / R ≤ 0.35. R1 / R can be 0.2, 0.22, 0.25, 0.3, 0.32, 0.34, 0.36, 0.38, 0.4, etc.

[0049] Within this range, the center of the electrode post can be clearly seen through the fixing hole 125, and the first substrate 141 has a sufficiently large area to receive the heat from the welder and weld together with the electrode post, ensuring the welding strength between the first substrate 141 and the electrode post. When this range is exceeded, the positioning hole 145 becomes too large, occupying too much area of ​​the first substrate 141, making it virtually impossible for the first substrate 141 to properly receive the heat from the welder and weld together with the electrode post. Furthermore, the contact area between the first substrate 141 and the electrode post is too small, failing to ensure the welding strength between the first substrate 141 and the electrode post. When this range is exceeded, the center of the electrode post cannot be observed through the positioning hole 145, thus making accurate positioning impossible.

[0050] The conductive foil 121 includes an electrical portion 123 and a buffer portion 124. Electrical portions 123 are respectively provided at opposite ends of the buffer portion 124. The buffer portion 124 protrudes along its thickness direction to form a buffer groove. Multiple electrical portions 123 and multiple buffer portions 124 are stacked along their thickness directions. Fixing holes 125 sequentially penetrate multiple electrical portions 123. The buffer groove can be a single wave or multiple waves. When the electrical portion 123 is subjected to tension, the buffer portion 124 will gradually unfold to offset the distance between the riveting members 14.

[0051] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indicator will also change accordingly.

[0052] It should also be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on the other component or may be connected to an intermediary component. When a component is referred to as being "connected to" another component, it can be directly connected to the other component or indirectly connected to the other component through an intermediary component.

[0053] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. When the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0054] The above description is only a preferred embodiment of the present utility model and does not limit the patent scope of the present utility model. All equivalent structural transformations made under the inventive concept of the present utility model using the contents of the present utility model specification and drawings, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present utility model.

Claims

1. A flexible connection strip, characterized in that The flexible connecting row comprises: a conductive piece comprising a plurality of conductive foils, the plurality of conductive foils being stacked along a thickness direction thereof, the conductive piece being provided with a fixing hole penetrating through the plurality of conductive foils in sequence; a riveting piece penetrating through the fixing hole and being riveted with the conductive piece.

2. The flexible connection strip of claim 1, wherein, The thickness of the conductive foil is D1 millimeter, 0.05≤D1≤0.

3.

3. The flexible connection strip of claim 1, wherein, The thickness of the conductive piece is D2 millimeter, 2≤D2≤4.

4. The flexible connection strip of claim 1, wherein, The riveting piece comprises a first base plate, a connecting plate and a second base plate, opposite ends of the connecting plate being connected with the first base plate and the second base plate respectively, the connecting plate penetrating through the fixing hole, the first base plate and the second base plate clamping the conductive piece together.

5. The flexible connection strip of claim 4, wherein, The first base plate and the connecting plate surround to form a welding groove, the first base plate being used to be electrically connected with a pole.

6. The flexible connection strip of claim 5, wherein, The first base plate is provided with a positioning hole along a thickness direction thereof, the positioning hole being communicated with the welding groove.

7. The flexible connection strip of claim 4, wherein, The width of the first base plate is L1, the diameter of the fixing hole is R, 0.4≤R / L1≤0.

7.

8. The flexible connection strip of claim 5, wherein, The width of the first base plate is L1, the width of the second base plate is L2, 0.4≤L2 / L1≤0.

9.

9. The flexible connection strip of claim 6, wherein, The diameter of the positioning hole is R1, the diameter of the fixing hole is R, 0.2≤R1 / R≤0.

4.

10. The flexible connection strip according to any one of claims 1 to 9, characterized in that The conductive foil comprises an electrical part and a buffer part, opposite ends of the buffer part being provided with the electrical part respectively, the buffer part protruding to form a buffer groove along a thickness direction thereof, the plurality of electrical parts being stacked along a thickness direction thereof, the plurality of buffer parts being stacked along a thickness direction thereof, the fixing hole penetrating through the plurality of electrical parts in sequence.

11. A battery pack, characterized by The battery pack comprises a plurality of single batteries (00) and the flexible connecting row according to any one of claims 1 to 10, the flexible connecting row being electrically connected with pole columns of adjacent single batteries (00) respectively.

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