Cylindrical battery

Abstract

The utility model provides a cylindrical battery, which belongs to the field of lithium batteries and comprises a shell. The roll core is arranged in the shell, and a center hole is formed in the center of the roll core; the end cover is arranged at the axial end part of the shell, and a pole is arranged on the end cover; the central column is arranged in the central hole in a penetrating manner; through holes are formed in the centers of the end covers; the pole is deviated from the center of the end cover and avoids the through hole; the two ends of the central column are connected with the two end covers respectively, and the two ends of the central column are communicated and communicated with the two through holes. According to the utility model, the central column is arranged between the two end covers, and the center of the assembled battery forms a pore channel structure through the hollow central column, so that heat in the center in the battery can be conducted out through the central column, and the pore channel structure formed by the central column can accelerate the heat dissipation effect of the battery in the use process; the long-term performance of the battery is improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to lithium battery technical field especially relates to a cylindrical battery. BACKGROUND

[0002] At present, lithium ion battery is the most suitable energy to replace gasoline at present stage, and cylindrical battery belongs to one implementation form of lithium ion battery, for example, the basic structure of the existing cylindrical lithium ion battery is disclosed in a kind of cylindrical lithium ion battery of Chinese patent CN109950450A, and it usually includes battery shell and the winding core received in battery shell.

[0003] At present, cylindrical battery capacity is bigger and bigger, and cylindrical battery size is bigger and bigger, and the rate performance and cycle performance of battery are higher and higher.But when battery size becomes large, heat production in battery during high-rate charge and discharge overcharge will be more serious, battery temperature is higher, and more side reactions of battery will directly affect the performance of battery.

[0004] In addition, winding core is wound by cylindrical winding needle during cylindrical battery production, and center hole exists in the center, and due to the expansion of positive and negative pole pieces during charge and discharge process, the stress relaxation of inner ring during cycle process will lead to the phenomenon that positive and negative poles are not well adhered, and further lead to the phenomenon that lithium is precipitated in the head of inner ring of winding core. INNOVATION CONTENT

[0005] Therefore, the utility model provides a cylindrical battery for solving the problem that heat production in battery is intensified during charge and discharge process when battery size becomes large, and it is difficult to realize heat dissipation in battery.

[0006] The technical scheme of the utility model is realized as follows: the utility model provides a cylindrical battery, which comprises a shell, a winding core arranged in the shell, a center hole arranged in the center of the winding core, two end covers arranged at the axial two ends of the shell, a pole post arranged on the end cover, a center column arranged in the center hole, wherein a through hole is arranged in the center of the end cover, the pole post is arranged away from the center of the end cover and avoids the through hole, the two ends of the center column are connected with the two end covers, and the two ends of the center column are connected with the two through holes.

[0007] On the basis of the above technical scheme, preferably, the cylindrical battery further comprises a current collecting disc arranged in the shell and located between the end face of the winding core and the end cover, and an insulating sheet arranged in the shell and located between the current collecting disc and the end cover, wherein a tab is arranged on the winding core, the current collecting disc is connected with the tab of the winding core, and the end of the center column penetrates the current collecting disc and the insulating sheet and extends outward.

[0008] Further preferably, the pole is arranged on the collecting plate and is arranged away from the center of the collecting plate; the end cover is provided with a corresponding hole on the insulating sheet, the hole is aligned with the pole, and when the end cover is arranged on the end of the shell, the pole extends out of the end cover through the hole.

[0009] Further preferably, the end cover is further provided with a liquid injection hole for supplementing electrolyte into the shell; and the insulating sheet is provided with an overflow hole through which the electrolyte enters the shell.

[0010] Further preferably, the collecting plate is provided with a window hole in the center, the center pole passes through the window hole, and the inner diameter of the window hole is greater than the outer diameter of the center pole.

[0011] Based on the above technical scheme, preferably, the inner wall of the center hole is tightly attached to the outer peripheral wall of the center pole, and the winding core is tightly sleeved on the center pole.

[0012] Based on the above technical scheme, preferably, the inner diameter of the center pole is not greater than 5mm.

[0013] Based on the above technical scheme, preferably, the wall thickness of the center pole is 1-3mm.

[0014] Based on the above technical scheme, preferably, further comprising a liquid cooling mechanism for conveying liquid cooling medium; and a liquid cooling pipe connected between the through hole and the liquid cooling mechanism and allowing the liquid cooling medium to flow through the center pole.

[0015] The cylindrical battery of the utility model has the following beneficial effects compared with the prior art:

[0016] (1) The center pole is arranged between the two end covers of the utility model, and after assembly, the center of the battery forms a channel structure through the hollow center pole, not only the heat in the center of the battery can be conducted out through the center pole, but also the channel structure formed by the center pole can accelerate the heat dissipation effect of the battery during use and improve the long-term performance of the battery.

[0017] (2) The winding core of the utility model is tightly wound on the center pole structure, which can support the winding core and prevent the inner ring of the winding core from collapsing during the later stage of circulation, thereby improving the circulation performance.

[0018] (3) The liquid cooling medium is conveyed to flow through the center pole through the liquid cooling mechanism and the liquid cooling pipe, further improving the heat dissipation efficiency of the battery. BRIEF DESCRIPTION OF DRAWINGS

[0019] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a perspective view of the cylindrical battery of this utility model;

[0021] Figure 2 This is a perspective view of the cylindrical battery of this utility model from another angle.

[0022] Figure 3 This is an axial cross-sectional view of the cylindrical battery of this utility model;

[0023] Figure 4 This is a top view of the collector plate of this utility model;

[0024] Figure 5 This is a top view of the insulating sheet of this utility model.

[0025] In the diagram: 1. Shell; 2. Core; 201. Center hole; 3. End cap; 31. Pole post; 301. Through hole; 302. Alignment hole; 303. Liquid injection hole; 4. Center post; 5. Collector plate; 501. Window hole; 6. Insulating sheet; 601. Flow hole; 7. Liquid cooling mechanism; 8. Liquid cooling pipe. Detailed Implementation

[0026] The technical solutions of this utility model will be clearly and completely described below with reference to the embodiments of this utility model. Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. Based on the embodiments of this utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of this utility model.

[0027] like Figure 1 As shown, combined with Figure 3 The present invention relates to a cylindrical battery, comprising a casing 1, a winding core 2, an end cap 3, and a central post 4.

[0028] Among them, shell 1 is a cylindrical tube.

[0029] The core 2 is set inside the housing 1, and a central hole 201 is provided in the center of the core 2. The central hole 201 is formed during the winding process of the core 2.

[0030] Two end covers 3 are arranged at the axial ends of the shell 1, and the two end covers 3 and the shell 1 form a closed cylindrical structure. The end cover 3 is provided with a pole column 31, and the pole columns 31 on the two end covers 3 are positive and negative poles respectively. The end cover 3 is provided with a through hole 301 in the center. The inner wall of the end of the shell 1 is provided with a step, and the edge of the end cover 3 is connected with the step to facilitate subsequent welding and fixation.

[0031] The center column 4 is arranged in the center hole 201, and the center column 4 is made of metal material to ensure its structural strength and heat conduction performance. The two ends of the center column 4 are connected with the two end covers 3 respectively, and the two ends of the center column 4 penetrate through and communicate with the two through holes 301, so that the cylindrical battery forms a structure similar to a ring. The inside of the center column 4 is a hollow structure. The advantage of this design is that when the battery is charging and discharging, the temperature in the center of the roll core 2 will rise and it is difficult for the heat to spread outward. The hollow center column 4 arranged in the center hole 201 of the roll core 2 can make the heat in the center of the roll core 2 conduct to the inside of the center column 4 and discharge outward, so as to realize effective heat dissipation in the center of the roll core 2 and improve the long-term performance of the battery. Since the through hole 301 is located at the center of the end cover 3, the pole column 31 needs to be arranged offset from the center of the end cover 3 and avoid the through hole 301.

[0032] In Figure 1 A preferred embodiment shown further includes a current collector plate 5 and an insulating sheet 6.

[0033] The roll core 2 is provided with a tab, and the roll core 2 adopts a full-tab rubbing flat structure, which can improve the rate performance of the battery and increase the heat dissipation effect of the battery.

[0034] The current collector plate 5 is used for welding with the tabs at the two ends of the roll core 2. The current collector plate 5 is arranged in the shell 1 and located between the end face of the roll core 2 and the end cover 3.

[0035] The insulating sheet 6 is arranged in the shell 1 and located between the current collector plate 5 and the end cover 3.

[0036] The end of the center column 4 penetrates through the current collector plate 5 and the insulating sheet 6 and extends outward, so that the current collector plate 5 and the insulating sheet 6 are sleeved on the center column 4.

[0037] In Figure 2 A preferred embodiment shown, since the through hole 301 is located at the center of the end cover 3, the pole column 31 is arranged on the current collector plate 5 and offset from the center of the current collector plate 5. The end cover 3 and the insulating sheet 6 are provided with a counter hole 302 corresponding to the pole column 31. When the end cover 3 is arranged on the end of the shell 1, the pole column 31 penetrates through the counter hole 302 and extends out of the end cover 3. An insulating ring is arranged between the counter hole 302 and the pole column 31 and welded, so as to avoid liquid leakage of the electrolyte in the shell 1 from the connection part of the counter hole 302 and the pole column 31.

[0038] InFigure 5 In a preferred embodiment shown, the end cover 3 is further provided with a liquid injection hole 303, through which electrolyte is supplemented into the shell 1; the insulation sheet 6 is provided with a flow hole 601, and a small gap is left between the insulation sheet 6 and the end cover 3, so that after the electrolyte is supplemented and injected from the liquid injection hole 303, it passes through the gap between the insulation sheet 6 and the end cover 3, and then flows into the shell 1 through the flow hole 601 to achieve liquid supplement.

[0039] In Figure 4 In a preferred embodiment shown, a window hole 501 is formed in the center of the current collector 5, the center column 4 passes through the window hole 501, and the inner diameter of the window hole 501 is greater than the outer diameter of the center column 4, so as to avoid the risk of electric leakage caused by the disconnection of the current collector 5 and the center column 4.

[0040] In Figure 3 In a preferred embodiment shown, the inner wall of the center hole 201 is in close contact with the outer peripheral wall of the center column 4, and the roll core 2 is tightly sleeved on the center column 4, at this time the center column 4 replaces the original center pin structure of the roll core 2, so as to support the roll core 2 in the later stage of battery cycle and prevent the inner ring of the roll core 2 from collapsing, thereby improving the cycle performance.

[0041] In Figure 3 In a preferred embodiment shown, the inner diameter of the center column 4 is not greater than 5 mm. If the inner diameter of the center column 4 is too small, it will affect the heat dissipation effect of the center of the roll core 2; if the inner diameter of the center column 4 is too large, it will waste the internal space of the shell 1, resulting in reduced battery efficiency.

[0042] In Figure 3 In a preferred embodiment shown, the wall thickness of the center column 4 is 1-3 mm. If the wall thickness of the center column 4 is too thick, it will weaken the efficiency of heat conduction from the center of the roll core 2 to the inside of the center column 4; if the wall thickness of the center column 4 is too thin, it may cause the inner wall of the battery to heat and expand, thereby causing the inner wall of the center column 4 to be squeezed and broken, resulting in the problem of electrolyte leakage in the shell 1 into the center column 4.

[0043] In Figure 3 In a preferred embodiment shown, in order to improve the heat dissipation efficiency of the battery, a liquid cooling mechanism 7 and a liquid cooling pipe 8 are further included.

[0044] The liquid cooling mechanism 7 is used to transport liquid cooling medium; the liquid cooling mechanism 7 can be a water cooling mechanism or an oil cooling mechanism, which stores liquid cooling medium, the liquid cooling medium is water or oil, and the liquid cooling medium is transported by a delivery pump.

[0045] The liquid cooling pipe 8 is connected between the through hole 301 and the liquid cooling mechanism 7 and makes the liquid cooling medium flow through the center column 4. The interface of the liquid cooling pipe 8 and the through hole 301 can be connected by screwing or interference fit.

[0046] The above merely describes preferred embodiments of the present application and is not intended to limit the present application, and any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A cylindrical battery, characterized in that, include: Shell (1); A core (2) is disposed inside the housing (1), and a central hole (201) is provided in the center of the core (2); Two end caps (3) are respectively disposed at both ends of the housing (1) along the axial direction, and pole posts (31) are disposed on the end caps (3); The central column (4) is inserted into the central hole (201); The end cap (3) has a through hole (301) in the center; The pole post (31) is offset from the center of the end cap (3) and avoids the through hole (301); The two ends of the central column (4) are connected to the two end caps (3) respectively, and the two ends of the central column (4) are connected to the two through holes (301).

2. A cylindrical battery according to claim 1, characterized in that, Also includes: The collector plate (5) is disposed inside the housing (1) and located between the end face of the core (2) and the end cap (3); An insulating sheet (6) is disposed inside the housing (1) and located between the collector plate (5) and the end cap (3); The core (2) is provided with a tab, and the collector plate (5) is connected to the tab of the core (2); The end of the central column (4) extends outward through the collector plate (5) and the insulating sheet (6).

3. A cylindrical battery according to claim 2, characterized in that: The pole post (31) is set on the collector plate (5) and offset from the center of the collector plate (5); The end cap (3) and the insulating sheet (6) are respectively provided with corresponding holes (302). The holes (302) are aligned with the pole post (31). When the end cap (3) is placed on the end of the housing (1), the pole post (31) extends out of the end cap (3) through the holes (302).

4. A cylindrical battery according to claim 2, characterized in that: The end cap (3) is also provided with a liquid injection hole (303) to replenish electrolyte into the housing (1) through the liquid injection hole (303); The insulating sheet (6) is provided with flow holes (601), and the electrolyte enters the interior of the housing (1) through the flow holes (601).

5. A cylindrical battery according to claim 2, characterized in that: The collector plate (5) has a window (501) in the center, and the central column (4) passes through the window (501). The inner diameter of the window (501) is larger than the outer diameter of the central column (4).

6. A cylindrical battery according to claim 1, characterized in that: The inner wall of the central hole (201) is in close contact with the outer peripheral wall of the central column (4), so that the core (2) is tightly fitted onto the central column (4).

7. A cylindrical battery according to claim 1, characterized in that: The inner diameter of the central column (4) is no greater than 5 mm.

8. A cylindrical battery according to claim 1, characterized in that: The wall thickness of the central column (4) is 1-3 mm.

9. A cylindrical battery according to claim 1, characterized in that, Also includes: Liquid cooling mechanism (7) is used to transport liquid cooling medium; A liquid cooling pipe (8) is connected between the through hole (301) and the liquid cooling mechanism (7) and allows the liquid cooling medium to flow through the central column (4).

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