Battery center tube and battery

Abstract

This application discloses a battery center tube and a battery. The battery center tube includes at least one curved section, which is annular and has an outer surface that can expand or contract toward or away from the inner surface of the battery's winding core. The curved section includes several folding units, which are arranged sequentially along the circular direction of the curved section, and the folding units are arranged to expand or contract at least along the circular direction of the curved section. This application provides a center tube structure that can expand or contract radially to fully fit into the battery's center hole. This center tube structure is particularly suitable for cylindrical lithium batteries. It addresses the problem of electrode sheet collapse within the center hole, which is caused by a mismatch between the outer wall of the center tube and the center hole of the battery, while also promoting electrolyte infiltration and internal gas flow, optimizing battery performance and improving the battery's cycle life. This application is lightweight and can somewhat increase the overall energy density of the battery.

Description

[Technical Field]

[0001] TECHNICAL FIELD This application relates to the technical field of batteries, and more particularly to battery center tubes and batteries.

[0002] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims priority to a Chinese patent application bearing application number "202322078683.X", filing date "August 3, 2023", and title "Battery Center Tube and Battery." [Background technology]

[0003] Currently, cylindrical batteries are generally manufactured using a winding process, and a center hole is formed in the center of the finished battery. During battery use, the electrode sheet in the center hole often collapses, especially in silicon anode systems that experience large expansion changes, resulting in a shortened battery life and even safety issues.

[0004] In the prior art, a common solution to this problem is to use a center tube positioned inside the center hole of the battery's winding core, which has proven effective. However, in actual use, there is often a certain deviation between the diameter of the center tube and the center hole of the battery, and the assembly process is also demanding. As a result, the outer wall of the cylindrical battery's center tube often does not fit tightly with the inner ring of the center hole of the winding core, easily causing the inside of the center hole to collapse. Furthermore, the wall of such a center tube hinders the infiltration of electrolyte and the flow of internal gas, thereby affecting battery performance. Summary of the Invention [Means for solving the problem]

[0005] In view of this, and to solve the above problems, the present application aims to provide a battery center tube, which includes at least one curved portion, the curved portion being annular, the outer side of the curved portion having an expanded state and a contracted state, the outer wall of the curved portion being close to the inner wall of the center hole of the battery when the curved portion is in the expanded state, and the outer wall of the curved portion being spaced apart from the inner wall of the center hole when the curved portion is in the contracted state, and the curved portion includes several folding units, the several folding units being sequentially arranged along the circular direction of the curved portion, each of the folding units having an unfolded state and a folded state, the folding unit being extended along the circular direction of the curved portion when the folding unit is in the unfolded state, and the folding unit being shortened along the circular direction of the curved portion when the folding unit is in the folded state.

[0006] In another preferred embodiment, each of the folding units includes at least a first part and a second part, a deformation angle is formed between the first part and the second part, and when the deformation angle increases, the folding unit extends, and when the deformation angle decreases, the folding unit shortens.

[0007] In another preferred embodiment, several of the distortion sections are arranged sequentially along the axial direction, and several of the distortion sections together present a tubular structure.

[0008] In another preferred embodiment, two adjacent distortion sections are directly or indirectly connected to each other.

[0009] In another preferred embodiment, two adjacent strain sections are indirectly connected to each other via a connecting section, and the connecting section is provided so as to extend along the axial direction of the strain section.

[0010] In another preferred embodiment, at least one mesh is formed between every two adjacent distortion portions.

[0011] In another preferred embodiment, the distortion portion is made of a metallic or non-metallic material.

[0012] In another preferred embodiment, the inner side of the deformation portion has at least one annular contact surface, and when the annular contact surface is subjected to a radially outward pressure, the folding unit elongates.

[0013] In another preferred embodiment, the pressure applying device further comprises a force applying device, said force applying device movably extending inside the straining portion, said force applying device being used to apply said pressure.

[0014] Another object of the present application is to provide a battery including any one of the battery center tubes described above. [Effects of the Invention]

[0015] By adopting the above technical solutions, the present application has the following positive effects over the prior art: The application of the present application provides a center tube structure that can expand or contract radially to fully fit into the battery's center hole. This center tube structure is particularly suitable for cylindrical lithium batteries, and it solves the problem of electrode sheet collapse within the center hole caused by the existing center tube's outer wall not fitting into the battery's center hole. At the same time, it promotes electrolyte infiltration and internal gas flow, optimizing battery performance and improving the battery's cycle life. The present application has a simple and lightweight structure, which can increase the overall energy density of the battery to a certain extent, and the assembly process is simple, reducing battery installation costs. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 2 is a schematic diagram of an expanded overall view of the battery center tube of the present application. [Figure 2] 1 is a schematic diagram of a distortion portion of a battery center tube of the present application. [Figure 3]1 is a schematic diagram illustrating the operation of the battery center tube force application device of the present application. [Figure 4] FIG. 2 is a three-dimensional schematic diagram of the tubular structure of the battery center tube of the present application. [Figure 5] 1 is an overall schematic diagram of a battery of the present application.

[0017] In the drawings, 1 straining part, 2 folding unit, 3 first part, 4 second part, 5 deformation angle, 6 tubular structure, 7 connection part, 8 mesh, 9 force application device, 10 annular contact surface, 11 battery. DETAILED DESCRIPTION OF THE INVENTION

[0018] The present application will be further described below in combination with drawings and specific examples, but is not limited to these.

[0019] As shown in Figures 1 and 2, a battery center tube is shown, which has at least one strained section 1, which is arranged in a ring shape, and the outside of the strained section 1 has an expanded state and a contracted state. When the strained section 1 is in an expanded state, the outer wall of the strained section 1 is close to the inner wall of the center hole of the battery, and when the strained section 1 is in a contracted state, the outer wall of the strained section 1 can be separated from the inner wall of the center hole. Here, the strained section 1 includes several folding units 2, which are arranged sequentially along the ring direction of the strained section 1, and each of the folding units 2 has an unfolded state and a folded state. When the folding unit 2 is in an unfolded state, the folding unit 2 extends along the ring direction of the strained section 1, and when the folding unit 2 is in a folded state, the folding unit 2 shortens along the ring direction of the strained section 1. Furthermore, as the folding unit 2 unfolds or folds, the outer diameter of the entire strained portion 1 increases or decreases accordingly, so that when the strained portion 1 is in a contracted state, the outer diameter of the strained portion 1 is smaller than the outer diameter of the center hole to facilitate assembly into the center hole, and when the strained portion 1 is in an expanded state, the outer diameter of the strained portion 1 is preferably equal to the inner diameter of the center hole to form a stable fitting support inside the center hole.

[0020] Furthermore, in one embodiment, each folding unit 2 includes at least a first portion 3 and a second portion 4, and a deformation angle 5 is formed between the first portion 3 and the second portion 4, and as the deformation angle 5 increases, the folding unit 2 extends, and as the deformation angle 5 decreases, the folding unit 2 shortens. Furthermore, when the deformation angles 5 of multiple folding units 2 in one distortion portion 1 increase simultaneously, the folding units 2 unfold so that the outer diameter of the distortion portion 1 increases.

[0021] Furthermore, in one embodiment, adjacent folding units 2 may be directly or indirectly connected.

[0022] Furthermore, in one embodiment, when each folding unit 2 is formed by directly connecting the first part 3 and the second part 4 at a deformation angle 5, the deformation angle 5 is formed inside one end where the first part 3 and the second part 4 are close to each other.

[0023] Furthermore, in one embodiment, the folding unit 2 is preferably capable of being extended or shortened by elastic or plastic deformation.

[0024] Furthermore, in one embodiment, the deformation of the folding unit 2 is achieved by a force including a radially outward force or an axially compressive force; specifically, in the case of the radially outward force, a radially outward force is applied to the inside of the distortion portion 1, and this force causes multiple folding units 2 in the circular direction of the same distortion portion 1 to move radially outward simultaneously, thereby progressing the unfolding of the folding units 2. Alternatively, when subjected to axial compression force, i.e., when the deformation angle 5 of the first part 3 and the second part 4 is small, the folding unit 2 formed by the first part 3 and the second part 4 has a large overall axial size, and when subjected to a vertical force, i.e., when this force is applied from top to bottom, from bottom to top, or simultaneously from top to bottom and centrally, the first part 3 and the second part 4 receive the force along the overall axis, forcing the deformation angle 5 to increase, and the axial size of the folding unit 2 decreases, but the annular size of the first part 3 and the second part 4 increases, thereby promoting the unfolding of the folding unit 2.

[0025] Furthermore, in one embodiment, the outer edges of the first portion 3 and the second portion 4 may both be V-shaped.

[0026] Furthermore, in one embodiment, each of the folding units 2 includes at least a third portion connected between the first portion 3 and the second portion 4 .

[0027] Furthermore, in one embodiment, when the axis of the distortion portion 1 is along the vertical direction, the first portion 3 and the second portion 4 may be arranged at an incline relative to the horizontal, and the third portion may be arranged at an incline or parallel to the horizontal.

[0028] Furthermore, in one embodiment, the outer edges of the first portion 3, the second portion 4 and the third portion may all be U-shaped or trapezoidal.

[0029] Furthermore, in one embodiment, both the first portion 3 and the second portion 4 are provided in an elongated structure, and preferably the first portion 3 and the second portion 4 are in a thread-like structure.

[0030] Furthermore, in one embodiment, the strain portion 1 may be configured by sequentially and alternately connecting a plurality of first portions 3 and a plurality of second portions 4, or may be configured by sequentially and alternately connecting a first portion 3, a second portion 4, and a third portion. By providing the strain portion 1 in this manner, it is possible to ensure that the strain portion 1 has excellent flexibility, and the outer diameter of the strain portion can be easily enlarged or reduced.

[0031] Furthermore, in one embodiment, the strained portion 1 exhibits a wave-like structure along the longitudinal direction.

[0032] Furthermore, in one embodiment, the distortion portion 1 has a helical structure along its longitudinal direction, the longitudinal direction of which is the circular direction of the distortion portion 1, and the helical structure includes several helical units that are deformable in the axial direction.

[0033] Furthermore, in one embodiment, several distortion sections 1 are provided sequentially along the axial direction, and several distortion sections 1 together present a tubular structure 6 .

[0034] Furthermore, in one embodiment, there is a direct or indirect connection between every two adjacent distortion portions 1 .

[0035] Furthermore, in one embodiment, two adjacent distortion portions 1 are indirectly connected to each other via connecting portions 7, and the connecting portions 7 are provided so as to extend along the axial direction of the distortion portions 1.

[0036] Furthermore, in one embodiment, the connection portion 7 has a thread-like structure extending along the axial direction.

[0037] Furthermore, in one embodiment, when the strain section 1 has a corrugated structure, the peak of the corrugated structure is connected to another adjacent strain section 1 above via a connecting section 7, and the valley of the corrugated structure is connected to another adjacent strain section 1 below via another connecting section 7.

[0038] Furthermore, in one embodiment, at least one mesh 8 is formed between every two adjacent distortion portions 1 .

[0039] Furthermore, in one embodiment, the mesh 8 preferably has an inner edge defined by an upper contortion portion 1, a lower contortion portion 1 and two adjacent connection portions 7.

[0040] Furthermore, as shown in FIG. 4, in one embodiment, the outer wall of the tubular structure 6 is preferably provided in a mesh form, and several meshes 8 arranged in an array are formed on the outer wall of the tubular structure 6.

[0041] Additionally, in one embodiment, the entire tubular structure 6 preferably has some degree of flexibility.

[0042] Furthermore, in one embodiment, the straining portion 1 is made of a metallic or non-metallic material.

[0043] Furthermore, in one embodiment, the metallic material is one or more of copper, aluminum-titanium alloy, nickel-titanium alloy, stainless steel, and cobalt-chromium alloy.

[0044] Additionally, in one embodiment, the non-metallic material is one or more of polypropylene, polyethylene, and polyethylene.

[0045] Furthermore, in one embodiment, the inner diameter of the tubular structure 6 preferably expands or contracts in the range of 0.1 mm to 10 mm.

[0046] The above are only preferred examples of the present application, and are not intended to limit the embodiments and protection scope of the present application.

[0047] Based on the above, the present application further has the following embodiments: In a further embodiment of the present application, the inner side of the straining portion 1 has at least one annular contact surface 10, and when the annular contact surface 10 is subjected to a radially outward pressure, the folding unit 2 is extended. Furthermore, when the outer side of the straining portion 1 is subjected to a radially inward pressure, the folding unit 2 can be shortened. In a further embodiment of the present application, the straining portion 1 further comprises a force applying device 9, which is movably extended inside the straining portion 1 and is used to apply pressure.

[0048] As shown in Fig. 3, in a further embodiment of the present application, the force application device 9 is an inflatable and deflated airbag structure. Furthermore, when a force is applied to the straining portion 1 by an airbag structure, the process is shown from left to right in Fig. 3. Specifically, the entire center tube is first extended into the center hole of the battery, and then the airbag structure is extended from top to bottom into the center hole, with the airbag structure in a compressed state. Then, the airbag structure is inflated, gradually expanding to create the above-mentioned pressure. After the entire center tube is expanded and fitted into the center hole of the battery, the airbag structure is deflated and compressed, and then the airbag structure is pulled out of the center hole, thereby completing the assembly of the center tube.

[0049] In a further embodiment of the present application, the airbag structure includes an air guide tube and an airbag body wrapped around the air guide tube, with one end of the air guide tube extending outward and connected to a corresponding inflation / deflation device.

[0050] In a further embodiment of the present application, when the strained portion 1 is subjected to radial pressure from the inside to the outside, the folding unit 2 expands in the annular direction of the strained portion 1 and contracts in the axial direction of the strained portion 1, i.e., when the folding unit 2 is deformed, the change in length along the annular direction of the strained portion 1 is opposite to the change in length in the axial direction, i.e., by applying a tensile force or pressure in the axial direction of the strained portion 1, the strained portion 1 can also be contracted or expanded in the annular direction.

[0051] In a further embodiment of the present application, in order to fit the strained portion 1 into the center hole of the battery, a force is applied to the strained portion 1 by a force application device 9 to deform it, and then an axial restriction is applied so that the strained portion 1 can be pre-controlled to maintain its expanded state without retracting to its original shape due to elasticity or other reasons, and at this time, the airbag structure is extended.

[0052] In further embodiments of the present application, the above-mentioned axial restriction may be provided by other structures of the battery, such as the top cover of the battery or the inner wall of the case, preferably with at least one annular restriction surface that at least abuts the upper end of the tubular structure 6 and leaves a hole for pulling out the airbag structure.

[0053] In further embodiments of the present application, the force application device 9 may be a rigid mechanical structure of other structural forms, preferably including at least two rigid arms that can be moved relatively close or far apart, and a control unit for providing a force to drive and move the two rigid arms to overcome the constraints of the distortion section 1.

[0054] 5, a preferred embodiment of a battery 11 is shown, which includes any of the battery center tubes described above. In one embodiment, the battery 11 further includes a battery body and a battery center tube disposed inside the battery body.

[0055] The above are merely preferred examples of the present application, and are not intended to limit the embodiments and protection scope of the present application. Those skilled in the art should understand that all solutions resulting from equivalent replacements and obvious modifications made using the contents shown in the specifications and drawings of the present application should be included in the protection scope of the present application.

Claims

1. 1. A battery center tube comprising: at least one strained portion, the strained portion (1) being annularly arranged; an outer side of the strained portion (1) having an expanded state and a contracted state; when the strained portion is in the expanded state, the outer wall of the strained portion is close to the inner wall of the center hole of the battery; and when the strained portion (1) is in the contracted state, the outer wall of the strained portion can be separated from the inner wall of the center hole; the strained portion (1) including several folding units (2), the several folding units (2) being arranged sequentially along the circular direction of the strained portion (1); each of the folding units (2) having an unfolded state and a folded state; when the folding unit (2) is in the unfolded state, the folding unit (2) extends along the circular direction of the strained portion (1); and when the folding unit (2) is in the folded state, the folding unit (2) shortens along the circular direction of the strained portion (1).

2. 2. The battery center tube according to claim 1, wherein each of the folding units (2) includes at least a first portion (3) and a second portion (4), a deformation angle (5) is formed between the first portion (3) and the second portion (4), and when the deformation angle (5) increases, the folding unit (2) extends, and when the deformation angle (5) decreases, the folding unit (2) shortens.

3. 2. The battery center tube according to claim 1, wherein several of the distortion portions (1) are arranged sequentially along the axial direction, and several of the distortion portions (1) together form a tubular structure (6).

4. The battery center tube according to claim 3, wherein two adjacent strained portions (1) are directly or indirectly connected to each other.

5. 5. The battery center tube according to claim 4, wherein adjacent two of the distortion portions (1) are indirectly connected via a connecting portion (7), and the connecting portion (7) is arranged to extend along the axial direction of the distortion portion (1).

6. 2. The battery center tube according to claim 1, wherein at least one mesh (8) is formed between every two adjacent distortion portions (1).

7. The battery center tube according to claim 1, characterized in that the straining portion (1) is made of a metallic or non-metallic material.

8. 2. The battery center tube according to claim 1, wherein the inside of the strain portion (1) has at least one annular contact surface (10), and when the annular contact surface (10) is subjected to radially outward pressure, the folding unit (2) elongates.

9. 9. The battery center tube of claim 8, further comprising a force application device (9), the force application device (9) movably extending inside the straining portion (1), the force application device (9) being used to apply the pressure.

10. 3. The battery center tube according to claim 2, wherein the strained portion (1) is formed by connecting a plurality of the first portions (3) and a plurality of the second portions (4) alternately in sequence.

11. 6. The battery center tube of claim 5, wherein the distorted portion (1) has a wave-shaped structure along its longitudinal direction, the peaks of the wave-shaped structure being connected to another adjacent distorted portion (1) above via the connecting portion (7), and the valleys of the wave-shaped structure being connected to another adjacent distorted portion (1) below via another connecting portion (7).

12. A battery comprising the battery center tube according to any one of claims 1 to 11.

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