Winding type hollow lithium ion battery

Abstract

The utility model discloses a winding type hollow lithium ion battery which comprises a shell, the shell comprises an inner shell and an outer shell, the inner shell and the outer shell are both of an annular structure, and the inner shell is sleeved with the outer shell; a heat dissipation cavity is formed in the side, away from the outer shell, of the inner shell, an annular cavity is formed between the inner shell and the outer shell, and the width of the annular cavity is larger than or equal to 1.5 mm. The shape of the roll core is matched with that of the annular cavity, and the roll core is contained in the annular cavity. Through the arrangement of the inner shell and the outer shell, the lithium ion battery is arranged to be of the hollow structure with the heat dissipation cavity, the inner side face of the roll core is arranged close to the inner shell, heat in the roll core can be dissipated from the inner shell, the outer side face of the roll core is arranged close to the outer shell, heat on the outer side face of the roll core can be dissipated from the outer shell, and the heat dissipation area of the roll core is increased; the heat dissipation effect of the roll core is improved, and the technical problem that the service life of a solid battery is affected due to local overheating caused by the fact that heat in the battery cannot be released along with the increase of the volume of the battery is solved.

Description

Technical Field

[0001] This utility model relates to the field of lithium-ion battery technology, specifically to a wound hollow lithium-ion battery. Background Technology

[0002] Existing lithium-ion batteries are typically monolithic, with mass-produced batteries mainly in square and cylindrical shapes. During charging and discharging, batteries generate heat, especially when multiple batteries are connected in series and parallel. At higher rates, the heat generated can become excessive, leading to localized overheating in the battery's center. This can affect battery lifespan and even safety. Currently, there is no effective method to control this localized overheating; improvement is limited to surface heat dissipation. Solving the heat dissipation problem of lithium-ion batteries remains a pressing technical challenge. Utility Model Content

[0003] To overcome the above-mentioned shortcomings, the purpose of this utility model is to provide a wound hollow lithium-ion battery to solve the problem that the heat generated by lithium-ion batteries, especially large lithium-ion batteries, cannot be released in a timely and effective manner during charging and discharging, thereby increasing the battery's service life and safety performance.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is: a wound hollow lithium-ion battery, comprising:

[0005] The housing includes an inner shell and an outer shell, both of which are annular structures, with the outer shell fitted onto the inner shell. A heat dissipation cavity is formed on the side of the inner shell away from the outer shell, and an annular cavity is formed between the inner shell and the outer shell. The width of the annular cavity is ≥1.5mm, and the width of the annular cavity is the distance between the outer shell and the inner shell.

[0006] The core is adapted to the shape of the annular cavity and is housed within the annular cavity.

[0007] Furthermore, the distance between the two opposite sides of the heat dissipation cavity is ≥10mm.

[0008] Furthermore, the inner shell and the outer shell have the same shape and the same axial height, and the centerline of the inner shell coincides with the centerline of the outer shell.

[0009] Furthermore, the housing also includes an upper shell and a lower shell, with the upper and lower ends of the inner shell and the outer shell respectively connected through the lower shell and the upper shell.

[0010] Furthermore, the inner shell and the outer shell are cylindrical shells, the radius of the inner shell is R1, the radius of the outer shell is R2, R1≥5mm, and R2-R1≥2mm.

[0011] Furthermore, the bottom and top surfaces of the cylindrical shell are circular or elliptical.

[0012] Furthermore, the inner shell and the outer shell are in the shape of a polygonal prism, and the bottom and top surfaces of the polygonal prism are polygons with the number of sides N≥4.

[0013] Furthermore, the distance from the side of the inner shell to the center line is L1, and the distance from the side of the outer shell to the center line is L2, where L1 ≥ 5mm and L2 - L1 ≥ 1.5mm.

[0014] Furthermore, the base and top surfaces of the polygonal prism are regular polygons.

[0015] Furthermore, the core includes a diaphragm, and positive and negative electrode plates disposed on both sides of the diaphragm. A negative electrode rivet is disposed on the upper shell. The negative electrode rivet and the upper shell are connected by an insulating sheet. The negative electrode rivet is connected to the negative electrode plate of the core through a negative electrode tab. The upper shell is connected to the positive electrode plate of the core through a positive electrode tab.

[0016] The beneficial effects of this utility model are:

[0017] 1) By designing the inner and outer shells, the lithium-ion battery is configured as a hollow structure with a heat dissipation cavity. The inner side of the core is positioned close to the inner shell, allowing heat to be dissipated from the core through the inner shell. The outer side of the core is positioned close to the outer shell, allowing heat to be dissipated from the outer shell. This increases the heat dissipation area of ​​the core and improves its heat dissipation effect. This solves the technical problem that as the size of the solid battery increases, the internal heat cannot be released, leading to localized overheating and affecting the battery's lifespan.

[0018] 2) By setting the battery as a hollow structure, hollow lithium-ion batteries can be customized with heat dissipation cavities of different shapes according to the specific needs of their assembly. In the special cylindrical space, space can be effectively utilized, achieving a perfect combination of battery and space, and making full use of the space of the special structure. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of the present invention. The illustrative embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention.

[0020] To more clearly illustrate the technical solutions in the embodiments of this utility model, the drawings used in the description of the embodiments 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 these drawings without creative effort.

[0021] Figure 1 This is a perspective view of a wound hollow lithium-ion battery according to an embodiment of the present invention.

[0022] Figure 2 This is a front view of a wound hollow lithium-ion battery according to an embodiment of the present invention;

[0023] Figure 3 This is a top view of a wound hollow lithium-ion battery according to an embodiment of the present invention.

[0024] Figure 4 This is a top view of a wound hollow lithium-ion battery according to another embodiment of the present invention;

[0025] Figure 5 This is a front view of a winding core according to an embodiment of the present invention;

[0026] Figure 6 This is a top view of the core of an embodiment of the present invention;

[0027] Figure 7 A front view of a traditional lithium-ion battery;

[0028] Figure 8 This is a top view of a traditional lithium-ion battery.

[0029] In the diagram: 1. Shell; 11. Inner shell; 12. Outer shell; 13. Lower shell; 14. Upper shell; 15. Annular cavity; 2. Heat dissipation cavity; 3. Core; 31. Inner side; 32. Outer side; 4. Insulating sheet; 5. Rivet; 6. Electrode; 7. Center line. Detailed Implementation

[0030] To make the above-mentioned objects, features, and advantages of this utility model more apparent and understandable, the specific embodiments of this utility model will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a full understanding of this utility model. However, this utility model can be implemented in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of this utility model. Therefore, this utility model is not limited to the specific embodiments disclosed below.

[0031] See appendix Figure 7 and 8As shown, conventional lithium-ion batteries are solid in the middle. This shape results in a large distance between the innermost and outermost layers, leading to the highest heat generation in the inner layer, which is difficult to dissipate. Therefore, this type of battery cannot effectively solve the heat dissipation problem. Furthermore, after prolonged use, the electrochemical reaction rate in the inner layer far exceeds that in the outer layer, potentially causing adverse reactions that severely impact battery lifespan and safety.

[0032] See appendix Figure 1-3 As shown, this embodiment of a wound hollow lithium-ion battery has a heat dissipation cavity 2 arranged in the axial direction of the battery, making the battery a hollow structure and solving the heat dissipation problem of the inner layer of the lithium-ion battery. Specifically, the lithium-ion battery includes a casing 1, which includes an inner casing 11 and an outer casing 12. The inner casing 11 and the outer casing 12 have the same shape, the same axial height, and different radial dimensions. The inner casing 11 is disposed inside the outer casing 12, and the center lines of the inner casing 11 and the outer casing 12 coincide. The upper and lower ends of the inner casing 11 and the outer casing 12 are connected by a lower casing 13 and an upper casing 14, respectively. An annular cavity 15 is formed between the inner casing 11 and the outer casing 12. The annular cavity 15 is used to place the core 3, and the heat dissipation cavity 2 is formed on the side of the inner casing 11 away from the outer casing 12. During the winding process of preparing the core 3, the shape of the core 3 is adapted to the shape of the annular cavity 15, so that the core 3 can be completely accommodated in the annular cavity 15.

[0033] By configuring the inner shell 11 and the outer shell 12, the lithium-ion battery is configured as a hollow structure with a heat dissipation cavity 2. The inner side 31 of the core 3 is located close to the inner shell 11, and the heat inside the core 3 can be dissipated from the inner shell 11. The outer side 32 of the core 3 is located close to the outer shell 12, and the heat on the outer side 32 of the core 3 can be dissipated from the outer shell 12. This increases the heat dissipation area of ​​the core 3, improves the heat dissipation effect of the core 3, and solves the technical problem that as the size of the physical battery increases, the internal heat of the battery cannot be released, resulting in local overheating and affecting the battery's service life.

[0034] On the other hand, existing lithium-ion batteries are solid batteries, and in some special cases, this integral battery type limits the design space of the battery. This application sets the battery as a hollow structure. The hollow lithium-ion battery can be customized with heat dissipation cavities 2 of different shapes according to the specific needs of its assembly. In the special cylindrical space, space can be effectively utilized, achieving a perfect combination of battery and space, and making full use of the space of the special structure.

[0035] In some embodiments, see Appendix Figure 3As shown, the inner shell 11 and outer shell 12 are cylindrical shells 1. The radius of the inner shell 11 is R1, and the radius of the outer shell 12 is R2. R1 ≥ 5mm, R2 - R1 ≥ 2mm. If R1 is too small, it will affect the heat dissipation effect of the winding core 3. If R1 ≥ 5mm, a heat dissipation cavity 2 with a radius of not less than 5mm is formed inside the battery for heat dissipation of the winding core 3. If R2 - R1 is too small, that is, the width of the annular cavity 15 accommodating the winding core 3 is too small, it is impossible to embed the winding core 3 into the shell 1. By limiting the size of R1 and R2, it is ensured that the winding core 3 can be smoothly installed into the annular cavity 15 and that the winding core 3 can obtain good heat dissipation.

[0036] In some embodiments, the bottom and top surfaces of the cylindrical housing 1 can be circular or elliptical, and the specific shape is set according to the installation space so that the battery can be perfectly integrated with the space and the space structure can be fully utilized.

[0037] In some embodiments, as shown in the appendix Figure 4 As shown, the inner shell 11 and outer shell 12 are shaped like polygonal prisms, with the base and top surfaces of the prisms being polygons. The number of sides of the polygons is N≥4. The distance from the side of the inner shell 11 to the center line is L1, and the distance from the side of the outer shell 12 to the center line is L2. L1≥5mm, and L2-L1≥1.5mm. By limiting the sizes of L1 and L2, it is ensured that the core 3 can be smoothly installed into the annular cavity, and that the core 3 can receive good heat dissipation. The number of sides of the polygon is 4, 5, 6, or any other arbitrary integer, specifically set according to the installation space. Preferably, the polygon is a regular polygon, that is, all sides are of equal length.

[0038] This application employs a corresponding circular or polygonal coil needle structure, wound into a corresponding core 3 structure as shown in the appendix. Figure 5 and attached Figure 6 As shown, the core 3 is then shaped according to the shape of the annular cavity 15. For example, if the annular cavity 15 is a hollow circular structure, it is shaped into a hollow circular core 3 structure; if the annular cavity 15 is a square structure, the core 3 is shaped into a corresponding polygon. The core 3 is then inserted into the annular cavity 15, and the upper shell 14 is welded on. The negative electrode tab 6 is then electro-welded to the negative electrode rivet 5. An insulating sheet 4 is fitted onto the negative electrode rivet 5 to insulate the negative electrode rivet 5 from the upper shell 14. The positive electrode tab 6 is then riveted to the upper shell 14, which is the positive electrode of the battery. Electrolyte is then injected, and finally, the battery top cover is welded on to complete the entire battery assembly.

[0039] In the description of this utility model, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this utility model and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model.

[0040] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0041] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it. They cannot be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be covered within the protection scope of this utility model.

Claims

1. A winding type hollow lithium ion battery, characterized by, include: The housing (1) includes an inner shell (11) and an outer shell (12), both of which are annular structures. The outer shell (12) is fitted onto the inner shell (11). A heat dissipation cavity (2) is formed on the side of the inner shell (11) away from the outer shell (12). An annular cavity (15) is formed between the inner shell (11) and the outer shell (12). The width of the annular cavity (15) is ≥1.5mm. The core (3) is adapted to the shape of the annular cavity (15) and is housed within the annular cavity (15).

2. The wound hollow lithium-ion battery according to claim 1, characterized in that, The distance between the two opposite sides of the heat dissipation cavity (2) is ≥10mm.

3. The wound hollow lithium-ion battery according to claim 1, characterized in that, The inner shell (11) and the outer shell (12) have the same shape and the same axial height, and the center line of the inner shell (11) coincides with the center line of the outer shell (12).

4. The wound hollow lithium-ion battery according to claim 1, characterized in that, The housing (1) further includes an upper shell (14) and a lower shell (13), and the upper and lower ends of the inner shell (11) and the outer shell (12) are connected by the lower shell (13) and the upper shell (14), respectively.

5. The wound hollow lithium-ion battery according to claim 1, characterized in that, The inner shell (11) and the outer shell (12) are cylindrical shells. The radius of the inner shell (11) is R1 and the radius of the outer shell (12) is R2. R1≥5mm and R2-R1≥2mm.

6. The wound hollow lithium-ion battery according to claim 5, characterized in that, The bottom and top surfaces of the cylindrical shell are circular or elliptical.

7. The wound hollow lithium-ion battery according to claim 1, characterized in that, The inner shell (11) and the outer shell (12) are in the shape of a polygonal prism, and the bottom and top surfaces of the polygonal prism are polygons with the number of sides N≥4.

8. The wound hollow lithium-ion battery according to claim 7, characterized in that, The distance from the side of the inner shell (11) to the center line (7) is L1, and the distance from the side of the outer shell (12) to the center line (7) is L2, where L1≥5mm and L2-L1≥1.5mm.

9. The wound hollow lithium-ion battery according to claim 7, characterized in that, The base and top surfaces of a polygonal prism are regular polygons.

10. The wound hollow lithium-ion battery according to claim 4, characterized in that, The core (3) includes a diaphragm, and positive and negative electrode plates disposed on both sides of the diaphragm. A negative electrode rivet (5) is disposed on the upper shell (14). The negative electrode rivet (5) and the upper shell (14) are connected by an insulating sheet (4). The negative electrode rivet (5) is connected to the negative electrode plate of the core (3) through a negative electrode tab. The upper shell (14) is connected to the positive electrode plate of the core (3) through a positive electrode tab.

Images