Battery center tube and battery

Abstract

The present application discloses a battery center tube and a battery. The battery center tube comprises: at least one deformation portion, wherein the deformation portion is annularly arranged, and the outer side of the deformation portion can be expanded or contracted to be close to or distant from the inner side of a roll core of a battery. The deformation portion comprises a plurality of folding units; the plurality of folding units are sequentially arranged in the circumferential direction of the deformation portion; and the folding units can be at least unfolded or folded to extend or shorten along the circumferential direction of the deformation portion. By means of the application of the present application, provided is a center tube structure which can be radially expanded or contracted to be fully fitted to a central hole of a battery, particularly suitable for cylindrical lithium batteries, thereby mitigating the problem of the collapse of the electrode sheet in the central hole caused by the outer walls of existing center tubes being not fitted to the central hole of the battery, promoting the infiltration of an electrolyte and flowing of internal gas, optimizing the performance of the battery, and prolonging the cycle service life of the battery. The present application achieves a light mass, and can improve the overall energy density of the battery to a certain extent.

Description

Battery center tube and battery

[0001] This application claims priority to the Chinese patent application with application number "202322078683.X", application date "August 3, 2023", and application name "A battery center tube and battery". Technical Field

[0002] The present application relates to the field of battery technology, and in particular to a battery central tube and a battery. Background Art

[0003] At present, cylindrical batteries are generally produced based on a winding process, and a center hole will be formed in the center of the battery when it is finished. During the use of the battery, especially for silicon negative electrode systems with large expansion changes, the center hole electrode often collapses, which leads to a shortened battery life and even safety problems.

[0004] In the prior art, a central tube placed inside the center hole of the battery core is often used to address this issue, with some success. However, in actual use, there is often a certain deviation between the diameter of the central tube and the size of the battery's center hole, and the assembly process is also demanding. As a result, the outer wall of the cylindrical battery's central tube often does not fit tightly against the inner ring of the core's center hole, which can easily lead to collapse inside the center hole. In addition, the wall of this type of central tube can hinder the infiltration of electrolyte and the flow of internal gas, affecting the battery's performance.

[0005] Summary of the Invention

[0006] In view of this, in order to solve the above problems, the purpose of the present application is to provide a battery center tube, comprising: at least one deformation portion, the deformation portion is arranged in a ring shape, and the outer side of the deformation portion has an expansion state and a contraction state, when the deformation portion is in the expansion state, the outer wall of the deformation portion is close to the inner wall of the center hole of the battery, when the deformation portion is in the contraction state, the outer wall of the deformation portion can be away from the inner wall of the center hole; wherein, the deformation portion includes a plurality of folding units, and the plurality of folding units are arranged in sequence along the circumferential direction of the deformation portion, each of the folding units has an expansion state and a folding state, when the folding unit is in the expansion state, the folding unit is extended along the circumferential direction of the deformation portion; when the folding unit is in the folding state, the folding unit is shortened along the circumferential direction of the deformation portion.

[0007] In another preferred embodiment, each of the folding units includes at least: a first part and a second part, and a deformation angle is formed between the first part and the second part; when the deformation angle increases, the folding unit is elongated; when the deformation angle decreases, the folding unit is shortened.

[0008] In another preferred embodiment, the plurality of deformation portions are sequentially arranged along the axial direction, and the plurality of deformation portions collectively form a tubular structure.

[0009] In another preferred embodiment, every two adjacent deformation parts are directly or indirectly connected.

[0010] In another preferred embodiment, each two adjacent deformation portions are indirectly connected via a connecting portion, and the connecting portion is extended along the axial direction of the deformation portion.

[0011] In another preferred embodiment, at least one mesh is formed between every two adjacent deformation portions.

[0012] In another preferred embodiment, the deformation portion is made of metal material or non-metal material.

[0013] 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 radial outward pressure, the folding unit extends.

[0014] In another preferred embodiment, the device further comprises: a force applying device, which is movably extended into the inner side of the deformation portion, and is used to provide the pressure.

[0015] The present application also aims to provide a battery comprising the battery central tube described in any one of the above.

[0016] Due to the adoption of the above-mentioned technical solution, the present application has the following positive effects compared with the prior art: through the application of the present application, a central tube structure is provided that can expand or contract radially to fully fit with the central hole of the battery, which is particularly suitable for cylindrical lithium batteries. It improves the problem of central hole pole piece collapse caused by the non-fitting of the outer wall of the existing central tube with the central hole of the battery, and at the same time promotes the infiltration of electrolyte and the flow of internal gas, optimizes the performance of the battery, and increases the cycle life of the battery; the present application has a simple structure and light weight, which can improve the overall energy density of the battery to a certain extent, and the assembly process is relatively simple, reducing the installation cost of the battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] FIG1 is a schematic diagram of the overall expansion of a battery center tube of the present application;

[0018] FIG2 is a schematic diagram of a deformation portion of a battery center tube according to the present application;

[0019] FIG3 is a schematic diagram of the working of a force-applying device for a battery central tube according to the present application;

[0020] FIG4 is a schematic perspective view of a tubular structure of a battery center tube according to the present application;

[0021] FIG5 is an overall schematic diagram of a battery of the present application.

[0022] In the accompanying drawings: 1. deformation portion; 2. folding unit; 3. first portion; 4. second portion; 5. deformation angle; 6. tubular structure; 7. connecting portion; 8. mesh; 9. force applying device; 10. annular contact surface; 11. battery. DETAILED DESCRIPTION

[0023] The present application will be further described below with reference to the accompanying drawings and specific embodiments, but they are not intended to limit the present application.

[0024] As shown in Figures 1 and 2, a battery center tube is shown, comprising: at least one deformation portion 1, the deformation portion 1 is arranged in a ring shape, and the outer side of the deformation portion 1 has an expansion state and a contraction state. When the deformation portion 1 is in the expansion state, the outer wall of the deformation portion 1 is close to the inner wall of the center hole of the battery, and when the deformation portion 1 is in the contraction state, the outer wall of the deformation portion 1 can be away from the inner wall of the center hole; wherein, the deformation portion 1 includes a plurality of folding units 2, and the plurality of folding units 2 are arranged in sequence along the circumferential direction of the deformation portion 1, and each folding unit 2 has an expansion state and a folding state. When the folding unit 2 is in the expansion state, the folding unit 2 extends along the circumferential direction of the deformation portion 1; when the folding unit 2 is in the folded state, the folding unit 2 shortens along the circumferential direction of the deformation portion 1. Furthermore, by expanding or folding the folding unit 2, the outer diameter of the entire deformation part 1 increases or decreases accordingly; thus, when the deformation part 1 is in a contracted state, the outer diameter of the deformation part 1 is smaller than the inner diameter of the center hole, so that it can be assembled into the center hole; when the deformation part 1 is in an expanded state, the outer diameter of the deformation part 1 is preferably equal to the inner diameter of the center hole, so as to form a stable fitting support on the inner side of the center hole.

[0025] Furthermore, in one embodiment, each folding unit 2 includes at least a first portion 3 and a second portion 4, with a deformation angle 5 formed between the first portion 3 and the second portion 4. When the deformation angle 5 increases, the folding unit 2 extends; when the deformation angle 5 decreases, the folding unit 2 shortens. Furthermore, when the deformation angles 5 of multiple folding units 2 in a deformable portion 1 increase simultaneously, the folding units 2 will expand, increasing the outer diameter of the deformable portion 1.

[0026] Furthermore, in one embodiment, adjacent folding units 2 may be directly connected or indirectly connected.

[0027] Furthermore, in one embodiment, when each folding unit 2 is formed by directly connecting the first portion 3 and the second portion 4 at a deformation angle 5 , the deformation angle 5 is formed on the inner side of one end where the first portion 3 and the second portion 4 are close to each other.

[0028] Furthermore, in one embodiment, the folding unit 2 can preferably be extended or shortened by elastic deformation or plastic deformation.

[0029] Further, in one embodiment, the deformation of the folding unit 2 is achieved by applying force, which includes radially outward force or axially compressive force; specifically, when the force is radially outward, a radially outward force is provided on the inner side of the deformation portion 1 to drive several folding units 2 on the same deformation portion 1 in an annular direction to move radially outward at the same time and drive the folding unit 2 to unfold; or when the force is axially compressive, that is, when the deformation angle 5 of the first part 3 and the second part 4 is small, the overall axial size of the folding unit 2 formed by the first part 3 and the second part 4 is large, and when a vertical force is received, that is, the force is applied from top to bottom, or from bottom to top, or simultaneously inward from top to bottom, the first part 3 and the second part 4 are forced along the overall axis to increase the deformation angle 5, the axial size of the folding unit 2 is reduced, and the annular size of the first part 3 and the second part 4 is increased and drives the folding unit 2 to unfold.

[0030] Furthermore, in one embodiment, the outer edges of the first portion 3 and the second portion 4 may be arranged together in a V-shape.

[0031] Furthermore, in one embodiment, each folding unit 2 includes at least a third portion connected between the first portion 3 and the second portion 4 .

[0032] Furthermore, in one embodiment, when the axis of the deformation portion 1 is along the vertical direction, the first portion 3 and the second portion 4 may be arranged tilted relative to the horizontal, and the third portion may be arranged tilted relative to the horizontal or parallel.

[0033] Furthermore, in one embodiment, outer edges of the first portion 3 , the second portion 4 and the third portion may be arranged in a U-shape or a trapezoidal shape.

[0034] Furthermore, in one embodiment, the first portion 3 and the second portion 4 are both arranged in an elongated structure, and the first portion 3 and the second portion 4 are preferably in a filamentous structure.

[0035] Furthermore, in one embodiment, the deformable portion 1 can preferably be composed of a plurality of first portions 3 and a plurality of second portions 4 connected alternately in sequence, or a first portion 3, a second portion 4, and a third portion connected alternately in sequence. This arrangement ensures that the deformable portion 1 has good flexibility, facilitating the increase or decrease of the outer diameter of the deformable portion.

[0036] Furthermore, in one embodiment, the deformation portion 1 presents a wave-shaped structure along its length direction.

[0037] Furthermore, in one embodiment, the deformation portion 1 is in a spiral structure along its length direction, the length direction of the spiral structure is the circumferential direction of the deformation portion 1, and the spiral structure includes a plurality of axially deformable spiral units.

[0038] Furthermore, in one embodiment, a plurality of deformation portions 1 are sequentially arranged along the axial direction, and the plurality of deformation portions 1 collectively form a tubular structure 6 .

[0039] Furthermore, in one embodiment, every two adjacent deformation parts 1 are directly or indirectly connected.

[0040] Furthermore, in one embodiment, every two adjacent deformation portions 1 are indirectly connected via a connection portion 7 , and the connection portion 7 is extended along the axial direction of the deformation portion 1 .

[0041] Furthermore, in one embodiment, the connecting portion 7 is a filamentous structure arranged along the axial direction.

[0042] Furthermore, in one embodiment, when the deformation portion 1 is a wave-shaped structure, the crest of the wave-shaped structure is connected to another adjacent deformation portion 1 on the upper side through a connecting portion 7, and the trough of the wave-shaped structure is connected to another adjacent deformation portion 1 on the lower side through another connecting portion 7.

[0043] Furthermore, in one embodiment, at least one mesh 8 is formed between every two adjacent deformation portions 1 .

[0044] Furthermore, in one embodiment, the mesh 8 is preferably defined at its inner edge by a deformation portion 1 on the upper side, a deformation portion 1 on the lower side, and two adjacent connecting portions 7 .

[0045] As shown in FIG. 4 , further, in one embodiment, the outer wall of the tubular structure 6 is preferably arranged in a mesh shape, and the outer wall of the tubular structure 6 is formed with a plurality of mesh holes 8 arranged in an array.

[0046] Furthermore, in one embodiment, the entire tubular structure 6 preferably has a certain degree of flexibility.

[0047] Furthermore, in one embodiment, the deformation portion 1 is made of metal material or non-metal material.

[0048] Furthermore, in one embodiment, the metal material is one or more of copper, aluminum-titanium alloy, nickel-titanium alloy, stainless steel and cobalt-chromium alloy.

[0049] Furthermore, in one embodiment, the non-metallic material is one or more of polypropylene, polyethylene and polytetrafluoroethylene.

[0050] Furthermore, in one embodiment, the inner diameter of the tubular structure 6 is preferably expanded or contracted within a size range of 0.1 mm to 10 mm.

[0051] The above description is merely a preferred embodiment of the present application and does not limit the implementation manner and protection scope of the present application.

[0052] Based on the above, this application also has the following implementation methods:

[0053] In a further embodiment of the present application, the inner side of the deformable portion 1 has at least one annular contact surface 10. When the annular contact surface 10 is subjected to radially outward pressure, the folding unit 2 extends. Furthermore, when the outer side of the deformable portion 1 is subjected to radially inward pressure, the folding unit 2 can also shorten. In a further embodiment of the present application, a force-applying device 9 is further included. The force-applying device 9 is movable and extends into the inner side of the deformable portion 1 to apply pressure.

[0054] As shown in Figure 3, in a further embodiment of the present application, the force-applying device 9 is an inflatable and deflable airbag structure. Furthermore, when the airbag structure applies force to the deformable portion 1, the process is as shown from left to right in Figure 3. Specifically, the entire center tube is first inserted into the center hole of the battery; then, the airbag structure is inserted from top to bottom into the inside of the center hole, at which point the airbag structure is in a compressed state; then, the airbag structure is inflated, gradually expanding and generating the aforementioned pressure; until the entire center tube is expanded and aligned with the center hole of the battery, the airbag structure is deflated and compressed, and then the airbag structure is withdrawn from the center hole, thereby completing the assembly of the center tube.

[0055] In a further embodiment of the present application, the airbag structure includes: an air guide tube and an airbag body wrapped around the outside of the air guide tube, and one end of the air guide tube extends outward and is connected to a corresponding inflation and deflation device.

[0056] In a further embodiment of the present application, when the deformation portion 1 is subjected to radial pressure from the inside to the outside, the folding unit 2 will extend in the circumferential direction of the deformation portion 1 and shorten in the axial direction of the deformation portion 1; that is, when the folding unit 2 is deformed, the change in its length along the circumferential direction of the deformation portion 1 is opposite to the change in its length in the axial direction; that is, the deformation portion 1 can be driven to contract or expand in the circumferential direction by applying tension or pressure in the axial direction of the deformation portion 1.

[0057] In a further embodiment of the present application, after the force-applying device 9 completes the deformation of the deformable portion 1 so that it fits the center hole of the battery, the deformable portion 1 can be controlled in advance by applying an axial limit so that it does not shrink back to its original shape due to elastic force or other reasons and remains in an expanded state. At this time, the airbag structure can be pulled out.

[0058] In a further embodiment of the present application, the above-mentioned axis limit can be provided by other structures of the battery, such as the upper cover or the inner wall of the shell of the battery, etc., preferably having at least one annular limiting surface, which at least abuts against the upper end of the tubular structure 6 and leaves a hole to allow the airbag structure to be withdrawn.

[0059] In a further embodiment of the present application, the force-applying device 9 may also be a rigid mechanical structure of other structural styles, preferably including at least two rigid arms that can be relatively close to or far away from each other, and a control unit, which is used to provide force to drive the two rigid arms to overcome the constraints of the deformation part 1 and move.

[0060] As shown in Figure 5, a preferred embodiment of a battery 11 is shown, comprising any one of the battery central tubes described above. Further, in one embodiment, the battery 11 comprises a battery body and a battery central tube disposed inside the battery body.

[0061] The above description is only a preferred embodiment of the present application and does not limit the implementation mode and protection scope of the present application. Those skilled in the art should be aware that any equivalent substitutions and obvious changes made using the description and illustrations of the present application should be included in the protection scope of the present application.

Claims

1. A battery center tube, characterized in that: include: At least one deformation part, the deformation part (1) is arranged in an annular shape, and the outer side of the deformation part (1) has an expansion state and a contraction state. When the deformation part is in the expansion state, the outer wall of the deformation part is close to the inner wall of the central hole of the battery, and when the deformation part (1) is in the contraction state, the outer wall of the deformation part can be away from the inner wall of the central hole; wherein the deformation part (1) comprises a plurality of folding units (2), and the plurality of folding units (2) are arranged in sequence along the circumferential direction of the deformation part (1), and each of the folding units (2) has an expansion state and a folding state. When the folding unit (2) is in the expansion state, the folding unit (2) is extended along the circumferential direction of the deformation part (1); when the folding unit (2) is in the folding state, the folding unit (2) is shortened along the circumferential direction of the deformation part (1).

2. The battery center tube according to claim 1, characterized in that: Each of the folding units (2) comprises at least: a first part (3) and a second part (4); a deformation angle (5) is formed between the first part (3) and the second part (4); when the deformation angle (5) increases, the folding unit (2) is extended; when the deformation angle (5) decreases, the folding unit (2) is shortened.

3. The battery center tube according to claim 1, characterized in that: The plurality of deformation parts (1) are arranged in sequence along the axial direction, and the plurality of deformation parts (1) together form a tubular structure (6).

4. The battery center tube according to claim 3, characterized in that: Each two adjacent deformation parts (1) are directly or indirectly connected.

5. The battery center tube according to claim 4, characterized in that: Each adjacent two deformation parts (1) are indirectly connected via a connection part (7), and the connection part (7) is arranged to extend along the axial direction of the deformation part (1).

6. The battery center tube according to claim 1, characterized in that: At least one mesh hole (8) is formed between each two adjacent deformation parts (1).

7. The battery center tube according to claim 1, characterized in that: The deformation part (1) is made of metal material or non-metal material.

8. The battery center tube according to claim 1, characterized in that: The inner side of the deformation portion (1) has at least one annular contact surface (10), and when the annular contact surface (10) is subjected to radial outward pressure, the folding unit (2) is extended.

9. The battery center tube according to claim 8, characterized in that: Also includes: A force applying device (9), wherein the force applying device (9) is movably extended into the inner side of the deformation portion (1), and the force applying device (9) is used to provide the pressure.

10. The battery center tube according to claim 2, characterized in that: The deformation portion (1) is composed of a plurality of the first portions (3) and a plurality of the second portions (4) which are connected alternately in sequence.

11. The battery center tube according to claim 5, characterized in that: The deformation portion (1) presents a wave structure along its length direction, the wave crest of the wave structure is connected to another adjacent deformation portion (1) on the upper side via the connecting portion (7), and the wave trough of the wave structure is connected to another adjacent deformation portion (1) on the lower side via another connecting portion (7).

12. A battery, characterized in that: The battery center tube comprises the battery center tube as described in any one of claims 1 to 11.

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