Core rod structure applied to winding type battery and lithium battery

Abstract

The utility model relates to the technical field of battery structures, in particular to a core rod structure applied to a winding type battery and a lithium battery, the core rod structure comprises a hollow core rod main body and a plurality of positive patterns or / and negative patterns positioned on the outer surface of the core rod main body, and the battery comprises the core rod structure. According to the core rod, the positive lines or / and the negative lines are arranged on the outer surface of the core rod main body, and the effective liquid guide channels are formed between the positive lines or in the negative lines, so that the problem that electrolyte is difficult to circulate and infiltrate a roll core structure at a position far away from a liquid injection port in the prior art is solved; the core rod can provide an active electrolyte channel to improve the cycle performance of the battery cell, the electrolyte in the channel is simultaneously contacted with the core rod and the battery cell, and the solid-liquid contact can effectively improve the heat conduction capability of the core rod; in addition, reinforcing ribs protruding relative to the outer surface of the core rod can be formed due to the arrangement of the male lines, so that the strength of the core rod is enhanced, and stronger structural supporting force is provided for the battery cell.

Description

Technical Field

[0001] The utility model relates to the technical field of lithium batteries, in particular to a core rod structure used for a winding type battery and a lithium battery. Background Art

[0002] A wound battery is also called a core-wound battery, in which a positive electrode sheet, a separator, and a negative electrode sheet are stacked in sequence and then wound to form a core-wound battery with a cavity. During the winding process, the positive electrode empty foil area and the negative electrode empty foil area extend out to form a positive electrode ear and a negative electrode ear at the end of the core-wound battery. A core rod is provided in the cavity, and the core and the core rod constitute a battery cell. The core rod provides structural support for the battery cell. The battery cell is loaded in a shell and sealed and fixed by the end cover assemblies at both ends of the shell.

[0003] like Figure 2 The figure shows the mainstream wound square case battery on the market. It is rectangular in shape as a whole. The flat oval core (left) made by winding is placed in the stamped shell (right) along the height direction of the battery. The positive and negative poles and the pressure relief valve are all located on the top of the battery. The middle of the flat oval core is provided with Figure 3 The hollow structure of the core rod shown. The applicant has also launched a new core rod wound battery, including: a winding core, a cover plate assembly, a temperature control channel interface and a shell, etc.; the winding core, the cover plate assembly, the temperature control channel interface and the shell are connected to form the battery; the winding core includes: a hollow pipe (core rod), a positive electrode sheet, a first diaphragm, a negative electrode sheet and a second diaphragm; the positive electrode sheet, the first diaphragm, the negative electrode sheet and the second diaphragm are stacked in sequence and wound in the center on the hollow pipe to form the winding core; a positive electrode ear is provided on one side of the positive electrode sheet of the winding core, and a negative electrode ear is provided on one side of the negative electrode sheet of the winding core, and the positive electrode ear and the negative electrode ear are located at the opposite ends of the hollow pipe (core rod) when stacked and wound.

[0004] However, whether it is the mainstream wound battery in the market or the new core rod wound battery proposed by the applicant, the core rod and the electrode are tightly fitted after hot pressing, and the winding structure is dense as a whole. After liquid is injected from the top or bottom of the outer shell, even if an injection channel is opened in the core rod through the top and bottom, it is difficult for the electrolyte to flow and infiltrate the winding core structure far away from the injection port. Moreover, the space between the electrode and the core rod is small and the liquid retention performance is poor. The diaphragm and the core rod are in solid contact and have poor thermal conductivity. The amount of internal electrolyte is small and the circulation performance is poor.

[0005] To this end, this application is filed. Utility Model Content

[0006] In view of the above-mentioned shortcomings of the prior art, the utility model provides a core rod structure and a lithium battery applied to a wound battery.

[0007] In order to achieve the above-mentioned purpose, the main technical solutions adopted by the utility model include:

[0008] On the one hand, the utility model provides a core rod structure applied to a wound battery.

[0009] A core rod structure used in a wound battery comprises a hollow core rod body and a plurality of positive and / or negative patterns on the outer surface of the core rod body.

[0010] The hollow core rod body not only helps to improve the space utilization of the battery, but also increases the heat dissipation area, reduces the occurrence of local high-temperature areas, promotes a more even distribution of heat inside the battery, and makes all positions inside the battery bear uniform force, reduces the consistency differences between battery cells, improves the overall performance of the battery pack, and facilitates recycling.

[0011] However, in the prior art, the winding structure is dense as a whole. After liquid is injected from the top or bottom of the outer shell, it is difficult for the electrolyte to flow and infiltrate the winding core structure at a position far away from the injection port. In addition, the space between the pole piece and the core rod is small and the liquid retention performance is poor. The diaphragm and the core rod are in solid contact and have poor thermal conductivity. The amount of internal electrolyte is small and the circulation performance is poor.

[0012] The utility model can improve the liquid injection effect and enhance the liquid retention capacity by arranging positive lines and / or negative lines on the outer surface of the core rod body, and forming an effective liquid conduction channel between the positive lines or in the negative lines. After the liquid conduction channel is formed, the core rod can provide an active electrolyte channel to enhance the battery cell cycle performance. The electrolyte in the channel is in contact with the core rod and the battery cell at the same time, and the solid-liquid contact can effectively enhance the thermal conductivity of the core rod. In addition, the arrangement of the positive lines will also form a reinforcing rib protruding relative to the outer surface of the core rod, which can enhance the strength of the core rod and help the core rod provide a stronger structural support for the battery cell.

[0013] Preferably, the core rod body is a prismatic structure, and the positive pattern and / or the negative pattern are arranged on the outer surface of the prismatic structure.

[0014] Preferably, the prism structure is selected from any one of a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism and an octagonal prism, and each corner of the prism is transitioned by an arc.

[0015] In this embodiment, the core rod body is selected from any one of a hollow triangular prism, quadrangular prism, pentagonal prism, hexagonal prism, and octagonal prism, that is, the inner wall of the core rod and the outer wall of the core rod have the same cross-sectional shape, both are selected from any one of a triangle, rectangle, pentagon, hexagon, and octagon, and the centers coincide.

[0016] In this embodiment, the arc-shaped transition edges help to reduce the gap between them and the winding core, making the internal structure of the battery compact and consistent, improving the energy density and cycle performance of the battery, and also preventing the diaphragm or other sensitive components inside the battery from being punctured, reducing stress concentration, and increasing heat dissipation.

[0017] Preferably, the positive pattern and / or the negative pattern are selected from any one or more of horizontal patterns, vertical patterns, threads and curved patterns; the horizontal patterns, vertical patterns, threads and curved patterns are raised relative to the outer surface of the core rod to form positive patterns, and liquid conducting channels are formed between adjacent positive patterns; the horizontal patterns, vertical patterns, threads and curved patterns are recessed relative to the outer surface of the core rod to form negative patterns, and the grooves of the negative patterns form liquid conducting channels; the positive patterns and negative patterns may be set selectively or simultaneously, and the methods for obtaining the positive patterns and / or the negative patterns include but are not limited to any existing or future methods for obtaining positive patterns and / or negative patterns such as surface etching, machining, casting, extrusion, etc.

[0018] Preferably, the mandrel body is a quadrangular prism, the length of the quadrangular prism is recorded as L1, the height of the quadrangular prism is recorded as H1, the width is recorded as T1, the radius of the arc is recorded as R1, the outer surface of the quadrangular prism is provided with a strip protrusion along its length direction, the length, width and height of the strip protrusion are recorded as L0, D0 and H0 respectively, the interval between two adjacent strip protrusions is recorded as S0, 1mm≤L1≤2000mm, 1mm≤H1≤1000mm, 10mm≤T1≤2000mm, 0mm <R1≤1000mm,0.1mm≤L0≤2000mm,0.1mm≤D0≤100mm,0.1mm≤H0≤10mm,0.1mm≤S0≤100mm。

[0019] Preferably, 50mm≤L1≤500mm, 1mm≤H1≤10mm, 10mm≤T1≤100mm, 0mm <R1≤10mm,50mm≤L0≤500mm,0.1mm≤D0≤0.3mm,0.1mm≤H0≤0.4mm,0.1mm≤S0≤0.5mm。

[0020] Preferably, L1 is 200 mm, H1 is 4 mm, T1 is 40 mm, R1 is 5 mm, L0 is 200 mm, D0 is 0.15 mm, H0 is 0.2 mm, and S0 is 0.15 mm.

[0021] Preferably, in addition to the prismatic structure, the core rod body may also be a cylindrical structure, and the positive pattern and / or the negative pattern are arranged on the outer surface of the cylindrical structure.

[0022] Preferably, the core rod body is integrally formed, and the material of the core rod body includes but is not limited to any one or more of aluminum, copper, zinc, magnesium, steel, chromium, and titanium; the inner wall of the core rod body is provided with an insulating layer, and the insulating layer is obtained by including but not limited to any existing or future coating acquisition methods such as oxidation, electroplating, spraying, coating, laser processing, and vapor deposition; the provision of the insulating layer can not only reduce the direct contact between the core rod and other conductive components inside the battery to avoid short circuits, but also play a certain protective role on the battery cells to prevent the battery cells from being mechanically damaged or chemically corroded during charging and discharging, and reduce the unstable performance of the battery due to current fluctuations or abnormalities during charging and discharging, thereby extending the service life of the battery.

[0023] On the other hand, the utility model also provides a lithium battery, which contains the core rod structure as described above. As for other components of the lithium battery, conventional technical means in the field are adopted.

[0024] The utility model can improve the liquid injection effect and enhance the liquid retention capacity by arranging positive lines and / or negative lines on the outer surface of the core rod body, and forming an effective liquid guide channel between the positive lines or in the negative lines. Compared with the prior art, the core rod structure proposed by the utility model helps to enhance the liquid injection capacity and liquid retention capacity of the wound battery, and can provide an active electrolyte channel to improve the battery cell cycle performance, improve the core rod thermal conductivity, thereby increasing the liquid retention capacity of the lithium battery and improving the performance of the lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic structural diagram of Example 1 of the utility model.

[0027] Figure 2 It is the mainstream wound square shell battery on the market.

[0028] Figure 3 for Figure 2 Schematic diagram of the structure of the core rod. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0030] Example 1

[0031] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1, and the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 200 mm, H1 is 4 mm, T1 is 40 mm, R1 is 5 mm, L0 is 200 mm, D0 is 0.15 mm, H0 is 0.2 mm, and S0 is 0.15 mm.

[0032] Example 2

[0033] Compared with Example 1, the specifications of the strip protrusions are adjusted, and the width, height and interval between adjacent strip protrusions are specifically: D0 is 0.5 mm, H0 is 0.2 mm, S0 is 0.15 mm. The rest are the same as Example 1.

[0034] Example 3

[0035] Compared with Example 1, the specifications of the strip protrusions are adjusted, and the width, height and interval between adjacent strip protrusions are specifically: D0 is 0.15 mm, H0 is 0.2 mm, S0 is 1 mm. The rest are the same as Example 1.

[0036] Example 4

[0037] Compared with Example 1, the specifications of the strip protrusions are adjusted, and the width, height and interval between adjacent strip protrusions are specifically: D0 is 0.15 mm, H0 is 0.5 mm, S0 is 0.15 mm. The rest are the same as Example 1.

[0038] Example 5

[0039] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1, and the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are specifically strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 50 mm, H1 is 1 mm, T1 is 10 mm, R1 is 0.1 mm, L0 is 50 mm, D0 is 0.1 mm, H0 is 0.1 mm, and S0 is 0.1 mm.

[0040] Example 6

[0041] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1, and the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 500 mm, H1 is 10 mm, T1 is 100 mm, R1 is 10 mm, L0 is 500 mm, D0 is 0.3 mm, H0 is 0.4 mm, and S0 is 0.5 mm.

[0042] Example 7

[0043] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1; the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 500 mm, H1 is 10 mm, T1 is 50 mm, R1 is 0.5 mm, L0 is 500 mm, D0 is 0.3 mm, H0 is 0.3 mm, and S0 is 0.1 mm.

[0044] Example 8

[0045] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1, and the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 50 mm, H1 is 1 mm, T1 is 100 mm, R1 is 5 mm, L0 is 50 mm, D0 is 0.1 mm, H0 is 0.4 mm, and S0 is 0.3 mm.

[0046] Example 9

[0047] A core rod structure for a wound battery comprises a hollow core rod body and a plurality of positive patterns on the outer surface of the core rod body, wherein the core rod body is a quadrangular prism, wherein each corner of the quadrangular prism is transitioned by an arc, wherein the length of the quadrangular prism is L1, the height is H1, and the width is T1, and the radius of the arc is R1, and the surface of the quadrangular prism is covered with positive patterns, wherein the positive patterns are strip-shaped protrusions arranged along the length direction of the quadrangular prism, wherein the length, width, and height of the strip-shaped protrusions are L0, D0, and H0, respectively, and the interval between two adjacent strip-shaped protrusions is S0, wherein L1 is 300 mm, H1 is 5 mm, T1 is 10 mm, R1 is 10 mm, L0 is 300 mm, D0 is 0.2 mm, H0 is 0.1 mm, and S0 is 0.5 mm.

[0048] Example 10

[0049] Compared with Example 1, the strip-shaped protrusion is adjusted to a strip-shaped groove consistent with its specifications, that is, the length, width and depth of the strip-shaped groove are 200 mm, 0.15 mm and 0.2 mm respectively, and the rest are consistent with Example 1.

[0050] Embodiment 11

[0051] A core rod structure for a wound battery comprises a hollow cylindrical core rod body and a plurality of strip protrusions arranged at intervals on the outer surface of the core rod body, wherein the cylindrical core rod body is 200 mm long, 30 mm in inner diameter and 40 mm in outer diameter, and the strip protrusions are arranged along the length direction of the cylindrical core rod and are spaced 0.15 mm apart from each other, and the length, width and height of the strip protrusions are 200 mm, 0.15 mm and 0.2 mm respectively.

[0052] Example 12

[0053] A core rod structure for a wound battery comprises a hollow cylindrical core rod body and a plurality of strip grooves arranged at intervals on the outer surface of the core rod body, wherein the cylindrical core rod body is 200 mm long, 30 mm in inner diameter and 40 mm in outer diameter, and the strip grooves are arranged along the length direction of the cylindrical core rod and are spaced 0.15 mm apart from each other, and the length, width and depth of the strip grooves are 200 mm, 0.15 mm and 0.2 mm, respectively.

[0054] Embodiment 13

[0055] A core rod structure for a wound battery comprises a hollow cylindrical core rod body and a plurality of strip protrusions and a plurality of strip grooves on the outer surface of the core rod body, wherein the cylindrical core rod body is 200 mm long, 30 mm in inner diameter and 40 mm in outer diameter, the strip protrusions and the strip grooves are arranged along the length direction of the cylindrical core rod and are spaced 0.15 mm apart from each other, the length, width and height of the strip protrusions are 200 mm, 0.15 mm and 0.2 mm respectively, and the length, width and depth of the strip grooves are 200 mm, 0.15 mm and 0.2 mm respectively.

[0056] Comparative Example 1

[0057] Compared with Example 1, no strip-shaped protrusions are provided on the outer surface of the quadrangular prism, and the rest are consistent with Example 1.

[0058] Comparative Example 2

[0059] Compared with Example 11, no positive or negative patterns are provided on the cylindrical core rod body.

[0060] The core rod structures obtained in each embodiment and comparative example were respectively assembled into test batteries, and electrochemical performance tests were carried out. After the tests, the battery cells were disassembled to observe whether the battery cells were damaged and the states of the pole pieces and diaphragms after disassembly. The liquid injection effect and liquid retention effect were qualitatively analyzed by color difference.

[0061] The specific assembly operation is as follows: the mass ratio of the positive electrode material system is the active material Li(Ni 0.9 Co 0.05 Mn 0.05)O2: conductive agent carbon nanotube: conductive agent Super P: binder PVDF = 98:0.5:0.5:1, the current collector is a 12μm thick carbon-coated aluminum foil, and the positive electrode material system is slurried, coated, and rolled to obtain a positive electrode sheet; the mass ratio of the negative electrode material system is active material carbon black: conductive agent Super P: dispersant carboxymethyl cellulose: binder styrene butadiene rubber = 96.3:1:1.2:1.5, the current collector is a 6μm thick copper foil, and the negative electrode material system is slurried, coated, and rolled to obtain a negative electrode sheet; the positive electrode sheet and the negative electrode sheet are wound and shaped with a 12μm thick ceramic-coated polyethylene separator to obtain a core; the core is welded with a cover plate, shelled, sealed, dried, injected, and formed to obtain a corresponding test battery, and the electrolyte uses 1M LiPF6 (the solvent is ethylene carbonate and diethyl carbonate in a volume ratio of 1:1).

[0062] The specific operation of the test is: 0.33C rate charge, 0.33C rate discharge, test voltage range is 2.8V-4.3V, temperature is 17-27℃, relative humidity is 10%-90%, atmospheric pressure is 86-106kPa, and the test capacity is not less than 80% of the cycle number.

[0063] After observation and testing:

[0064] (1) With the same liquid injection volume, compared with Comparative Example 1, the liquid injection time required for Examples 1 to 10 is shortened to varying degrees, and the liquid retention volume is increased to varying degrees, and the liquid retention effect is relatively good. After disassembling Comparative Example 1, it was found that the battery cell was bruised, while no visible damage was observed in the battery cells of Examples 1 to 10.

[0065] Further, the number of cycles of the test battery assembled in comparative example 1 with a capacity of not less than 80% was measured to be 3614 times, while the number of cycles of Examples 1 to 10 was between 4508 and 6230 times, especially Example 1, which had the highest number of cycles, up to 6230 times. Compared with Example 1, Example 2, Example 3, and Example 4 sequentially increased the width, spacing, and height of the strip protrusions. We found that these adjustments, compared with Example 1, would degrade the cycle performance to varying degrees. The number of cycles of Example 2, Example 3, and Example 4 were 5642, 5129, and 5543, respectively. Obviously, if the width of the strip protrusion is too wide or the height is too high, the liquid guide channel will be too large, the liquid retention amount will be too much, and it will occupy the battery space, resulting in a decrease in the energy density of the battery; if the number of strip protrusions is small, the distribution is too sparse, the number of liquid guide channels is limited, the liquid retention amount is too small, and too much or too little liquid retention amount will have an adverse effect on the cycle performance of the battery.

[0066] In Examples 1 to 10, since the outer surface of the core rod body is provided with positive patterns (strip-shaped protrusions) or negative patterns (strip-shaped grooves), there is a gap between the winding core and the core rod structure, and the gap constitutes a liquid guide channel. Therefore, compared with Comparative Example 1 in which no positive patterns or negative patterns are provided, the core rod structures proposed in each embodiment of the utility model are convenient for the electrolyte to flow and infiltrate the winding core at a position away from the liquid injection port, and then fully infiltrate the positive and negative electrode sheets, thereby improving the wetting effect of the positive and negative electrode sheets. The existence of the gap increases the space between the electrode sheets and the core rod structure, significantly enhances the liquid retention capacity, improves the solid-liquid contact thermal conductivity between the diaphragm and the core rod, and the increase in internal electrolyte also helps to improve the cycle performance.

[0067] (2) With the same injection volume, compared with Comparative Example 2, the injection time required for Examples 11-13 is shortened to varying degrees, and the amount of liquid retained is increased to varying degrees, and the liquid retention effect is significantly improved. After disassembly of Comparative Example 2, it was found that the battery cell was damaged, while no visible damage was observed in the battery cells of Examples 11-13. After testing, the number of cycles of Comparative Example 2, Example 11, Example 12, and Example 13 were 3920 times, 5568 times, 5387 times, and 4834 times, respectively. In addition, we found that the support strength of the core rod structure in Example 11 was relatively the highest, followed by Example 13, Comparative Example 2, and Example 12. Obviously, the setting of the strip protrusion will strengthen the structural strength of the core rod, while the strip groove will crack the structural strength of the core rod. Moreover, although the simultaneous setting of positive and negative patterns can also improve the cycle performance of the battery to a certain extent, it is not conducive to improving the energy density of the battery.

[0068] In summary, the core rod structure proposed in the utility model helps to enhance the liquid injection and liquid retention capabilities of the wound battery, and can provide an active electrolyte channel to improve the battery cell cycle performance and improve the core rod thermal conductivity, thereby increasing the liquid retention capacity of the lithium battery and improving the performance of the lithium battery.

[0069] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. A person skilled in the art may change, modify, replace and deform the above embodiments within the scope of the present invention. In addition, a person skilled in the art may combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

Claims

1. A core rod structure for a wound battery, characterized in that: It comprises a hollow core rod body and a plurality of positive and / or negative patterns on the outer surface of the core rod body.

2. The core rod structure for a wound battery according to claim 1, characterized in that: The core rod body is a prismatic structure, and the positive pattern and / or the negative pattern are arranged on the outer surface of the prismatic structure.

3. The core rod structure for a wound battery according to claim 2, characterized in that: The prism-shaped structure is selected from any one of a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism and an octagonal prism, and each corner of the prism-shaped structure adopts an arc transition.

4. The core rod structure for a wound battery according to claim 1, characterized in that: The positive pattern and / or the negative pattern are selected from any one or more of horizontal patterns, vertical patterns, spiral patterns, and curved patterns.

5. The core rod structure for a wound battery according to claim 3, characterized in that: The mandrel body is a quadrangular prism, the length of the quadrangular prism is recorded as L1, the height of the quadrangular prism is recorded as H1, the width is recorded as T1, the radius of the arc is recorded as R1, the outer surface of the quadrangular prism is provided with strip protrusions along its length direction, the length, width and height of the strip protrusions are recorded as L0, D0 and H0 respectively, the interval between two adjacent strip protrusions is recorded as S0, 1mm≤L1≤2000mm, 1mm≤H1≤1000mm, 10mm≤T1≤2000mm, 0mm <R1≤1000mm,0.1mm≤L0≤2000mm,0.1mm≤D0≤100mm,0.1mm≤H0≤10mm,0.1mm≤S0≤100mm。 6. The core rod structure for a wound battery according to claim 5, characterized in that: 50mm≤L1≤500mm, 1mm≤H1≤10mm, 10mm≤T1≤100mm, 0mm <R1≤10mm,50mm≤L0≤500mm,0.1mm≤D0≤0.3mm,0.1mm≤H0≤0.4mm,0.1mm≤S0≤0.5mm。 7. The core rod structure for a wound battery according to claim 6, characterized in that: L1 is 200mm, H1 is 4mm, T1 is 40mm, R1 is 5mm, L0 is 200mm, D0 is 0.15mm, H0 is 0.2mm, and S0 is 0.15mm.

8. The core rod structure for a wound battery according to claim 1, characterized in that: The core rod body is a cylindrical structure, and the positive pattern and / or the negative pattern are arranged on the outer surface of the cylindrical structure.

9. The core rod structure for a wound battery according to any one of claims 1 to 8, characterized in that: The core rod body is integrally formed, and an insulating layer is provided on the inner wall of the core rod body.

10. A lithium battery, characterized in that: Contains the core rod structure according to any one of claims 1 to 9.

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