CN220066039U - Cylindrical battery and battery module - Google Patents

Abstract

The utility model relates to the technical field of batteries, in particular to a cylindrical battery and a battery module, wherein the cylindrical battery comprises: the shell is cylindrical, and the two ends of the shell are covered with a top cover and a bottom cover; the winding core is led out from one end of the top cover towards the positive electrode lug and the negative electrode lug; the pole is installed on the top cover in an insulating manner; the first confluence part is arranged between the winding core and the top cover in an insulating way with the shell and comprises an anode connecting area and a pole connecting area; the second confluence part is arranged between the winding core and the top cover and comprises a negative electrode connection area and a shell connection area; the pole extends laterally towards the pole connection region to form a lateral extension, and the lateral extension is connected with the pole connection region. According to the utility model, the internal resistance of the cylindrical battery is reduced by reducing the distance between the positive electrode and the negative electrode, the heat generation amount during charging and discharging is reduced, the requirement of rapid charging and discharging of the cylindrical battery is met, the wettability of the battery core by the electrolyte is improved, the production and processing procedures are effectively simplified, and the production and processing efficiency is improved.

Description

Cylindrical battery and battery module

Technical Field

The utility model relates to the technical field of batteries, in particular to a cylindrical battery and a battery module.

Background

Along with the development of lithium battery technology and the expansion of application scenes, the energy density requirement of the battery core is higher and higher, and the cylindrical lithium ion battery can realize higher energy density due to higher assembly ratio, so that the battery is widely applied, and the problem to be considered in the design process of the cylindrical lithium ion battery is that the battery internal resistance is required to be reduced while the energy density is improved, so that the heating value is reduced, and the most common mode for reducing the battery internal resistance at present is to adopt a battery tab structure with full tabs.

In the cylindrical lithium ion battery with a full tab structure in the prior art, positive and negative tabs are respectively arranged at two ends of a winding core, the tabs at the two ends are kneaded into end faces through a kneading process and then are respectively connected with positive and negative terminals of the battery, and the internal resistance of the kneaded tabs is smaller than that of the single-pole tabs, so that the battery heating value is reduced, but the prior art has at least the following defects: 1. the positive and negative electrode lugs are positioned on different sides of the battery, so that the overall internal resistance of the battery winding core is increased, the heat generation during charging and discharging is increased, the battery winding core is not suitable for rapid charging and discharging requirements, during assembling of the second winding core and the winding core, the lugs at two ends of the battery are required to be assembled by steps, the winding core infiltration difficulty and the infiltration time are increased due to the fact that the compact end faces after being kneaded are in the liquid injection process, the overall production and processing procedures are complex, and the production efficiency is low.

Disclosure of Invention

In view of the above drawbacks of the prior art, the present utility model is directed to a cylindrical battery and a battery module, which are used for solving the problems that in the prior art, positive and negative tabs of a cylindrical lithium ion battery with a full tab structure are located at different sides of the battery, so that the overall internal resistance of a battery winding core is increased, the heat generation during charging and discharging is increased, the requirement of rapid charging and discharging is not met, the overall production and processing procedures are complicated, and the production efficiency is low.

To achieve the above and other related objects, in a first aspect, the present utility model provides a cylindrical battery comprising:

the shell is cylindrical, and the two ends of the shell are covered with a top cover and a bottom cover;

the winding core is arranged in the shell, and one end of the winding core, which faces the top cover, is led out with a positive electrode lug and a negative electrode lug;

the pole is arranged on the top cover of the shell and is arranged between the pole and the top cover in an insulating way;

the first confluence part is arranged between the winding core and the top cover in an insulating way and comprises a positive electrode connection area electrically connected with the positive electrode lug and a pole connection area electrically connected with the pole;

the second confluence part is arranged between the winding core and the top cover and comprises a negative electrode connection area electrically connected with the negative electrode lug and a shell connection area directly or indirectly electrically connected with the shell towards one side of the top cover;

the pole extends laterally towards the pole connection region to form a lateral extension, and the lateral extension is electrically connected with the pole connection region.

Further, the cylindrical battery further comprises an insulating disc located between the winding core and the top cover, the first bus component and the second bus component are embedded on the insulating disc at intervals to form a bus disc, the pole connection area and the shell connection area are exposed from the bus disc towards one side of the top cover, and the positive electrode connection area and the negative electrode connection area are exposed from the bus disc towards the winding core.

Further, the pole connection region and the housing connection region are provided with a plurality of protruding structures toward the top cover.

Further, a plurality of groups of protruding areas are arranged on the pole connection area and the shell connection area at intervals along the circumferential direction of the bus plate, connection parts are formed between the adjacent protruding areas, and each group of protruding areas comprises a plurality of bosses arranged along the radial direction of the bus plate.

Further, a conductor block is connected between the inner wall of the top cover of the housing and the second bus member.

Further, the boss abuts against the conductor block, and the connecting portion is welded with the conductor block.

Further, the top cover is provided with an insulating part, the pole is separated from the shell through the insulating part, the insulating part is provided with a mounting hole, and the conductor block is positioned in the mounting hole and is separated from the pole through the insulating part.

Further, the conductor block and the second bus member are made of copper, the pole and the first bus member are made of aluminum, and the area of the positive electrode connection region is larger than that of the negative electrode connection region.

Further, the positive electrode connection region of the first bus member covers the positive electrode tab, the negative electrode connection region of the second bus member covers the negative electrode tab, and an area of the positive electrode tab covered by the positive electrode connection region is larger than an area of the negative electrode tab covered by the negative electrode connection region.

Further, the positive electrode tab and the negative electrode tab are respectively led out in the form of multipolar tabs to form sector areas.

Further, the first and second bus members are in a fan-shaped structure, and the positive electrode connection region and the negative electrode connection region are in a fan-shape.

Further, the lateral extension is scalloped, and covers the pole connection region.

Further, the top cover is integrally formed at the top end of the shell, and the edge of the bottom cover is overlapped with the edge of the bottom end of the shell and is turned over to form a winding structure.

In a second aspect, the utility model also provides a battery module, which comprises a box body and a plurality of cylindrical batteries accommodated in the box body.

As the positive electrode lug and the negative electrode lug are arranged at the same end of the winding core, the spacing between the positive electrode lug and the negative electrode lug is reduced, so that the internal resistance of the cylindrical battery is reduced when the current is conducted, the heat generation amount of the cylindrical battery during charge and discharge is reduced, the requirement of quick charge and discharge of the cylindrical battery is met, meanwhile, the first converging part and the second converging part are respectively arranged at the same end to converge the positive electrode lug and the negative electrode lug, the rolling and leveling and the related process steps in the full-electrode lug battery are simplified, the wettability of electrolyte to the battery core is improved, the production and processing procedures of the cylindrical battery are effectively simplified, and the production and processing efficiency is improved.

Drawings

Fig. 1 is a front sectional view of a top cap of a cylindrical battery according to an exemplary embodiment of the present utility model;

FIG. 2 is a front view of a winding core according to an exemplary embodiment of the present utility model;

FIG. 3 is a top view of a winding core according to an exemplary embodiment of the present utility model;

fig. 4 is a front cross-sectional view of a confluence plate according to an exemplary embodiment of the present utility model;

FIG. 5 is a top view of a busway tray according to an exemplary embodiment of the present utility model;

FIG. 6 is a top view of a buss bar plate after welding according to an exemplary embodiment of the present utility model;

FIG. 7 is a schematic view of an anode unwinding structure of a winding core according to an exemplary embodiment of the present utility model;

fig. 8 is a schematic structural view of a bottom cover end according to an exemplary embodiment of the present utility model;

fig. 9 is a schematic structural view of a bottom cover of a cylindrical battery according to another exemplary embodiment of the present utility model.

Description of the part reference numerals

1-a housing; 101-top cover; 102-winding structure; 11-a bottom cover; 111-sealing rings; 2-pole; 201-lateral extension; 3-winding the core; 301-positive plate; 3011-a ceramic layer; 31-positive electrode lugs; 32-negative electrode ear; 4-confluence plate; 401-boss; 402-laser welding spots; 41-a first converging part; 411-post connection region; 412-positive electrode connection region; 42-a second converging member; 421-housing attachment zone; 422-negative electrode connection region; 43-insulating discs; 5-conductor blocks; 6-insulating member.

Detailed Description

Further advantages and effects of the present utility model will become apparent to those skilled in the art from the disclosure of the present utility model, which is described by the following specific examples.

It should be understood that the structures, proportions, sizes, etc. shown in the drawings are for illustration purposes only and should not be construed as limiting the utility model to the extent that it can be practiced, since modifications, changes in the proportions, or otherwise, used in the practice of the utility model, are not intended to be critical to the essential characteristics of the utility model, but are intended to fall within the spirit and scope of the utility model. Also, the terms "upper", "lower", "left", "right", "middle" and "first", "second", etc. are used herein for descriptive purposes only and are not intended to limit the scope of the utility model for which the utility model may be practiced, but rather the relative relationships may be altered or modified without materially altering the technical context.

In one embodiment, the present utility model exemplarily shows a cylindrical battery, referring to fig. 1 to 5, which includes at least a case 1, a winding core 3, a pole 2, a first bus member 41, and a second bus member 42, wherein the structures of the respective portions are described in detail as follows:

the case 1 is a case structure for accommodating the winding core 3, for forming a sealed space for electrode reaction, the case 1 is cylindrical, both ends of which are capped with the top cover 101 and the bottom cover 11, the top cover 101 and the bottom cover 11 are used to participate in the structure constituting the internal seal of the case 1 from both ends of the cylindrical case 1, and in some embodiments, the top cover 101 and the bottom cover 11 may be fixed to both ends of the case 1 by a connection means such as welding.

The winding core 3 is disposed in the housing 1, the positive electrode tab 31 and the negative electrode tab 32 are led out from one end of the winding core 3 towards the top cover 101, the winding core 3 refers to a battery core formed by winding a positive electrode sheet and a negative electrode sheet, for convenience in understanding, please refer to fig. 7, which schematically illustrates a positive electrode unfolding structure of the winding core 3, that is, the positive electrode sheet 301, and a plurality of positive electrode tabs 31 are led out from the upper end of the positive electrode sheet 301, so after winding, the positive electrode tab 31 is led out from the end of the winding core 3, and the positive electrode tab 31 is obtained, for example, by a gap die cutting manner, in this embodiment, the upper edge of the positive electrode sheet 301 is further coated with a ceramic layer 3011 for improving the corrosion resistance of the positive electrode sheet 301, which is beneficial to prolonging the service life of the cylindrical battery, and also isolating the positive electrode sheet and the negative electrode sheet from short circuit abnormality.

The pole 2 is arranged on the top cover 101 of the casing 1 in a penetrating manner, and is arranged with the top cover 101 in an insulating manner, the pole 2 and the top cover 101 can be arranged in a common pole 2 mounting manner such as injection molding, jogging, clamping and the like, for example, in the embodiment, a ring groove is arranged on the side wall of the pole 2, the top cover 101 is clamped in the ring groove, and the pole 2 and the top cover 101 can be arranged in an insulating manner by arranging an insulating structure formed by injection molding or single molding, for example, in the embodiment, plastic is injected between the pole 2 and the top cover 101, the plastic is filled in the ring groove on the side wall of the pole 2, and the pole 2 and the top cover 101 are relatively fixed while insulating.

The first current collecting member 41 is disposed between the winding core 3 and the top cover 101, and is disposed with insulation between the first current collecting member 41 and the housing 1, the first current collecting member 41 includes a positive electrode connection region 412 electrically connected with the positive electrode tab 31, and a pole connection region 411 electrically connected with the pole 2, specifically, the pole 2 extends laterally toward the pole connection region 411 to form a lateral extension 201, that is, a plate structure located above the pole connection region 411 of the first current collecting member 41, and the lateral extension 201 is electrically connected with the pole connection region 411 to conduct the first current collecting member 41 with the pole 2.

The second bus member 42 is disposed between the winding core 3 and the top cover 101, and includes a negative electrode connection region 422 electrically connected to the negative electrode tab 32, and a case connection region 421 directly or indirectly electrically connected to the case 1 toward one side of the top cover 101, it being understood that when the negative electrode tab 32 is provided in plurality, the negative electrode connection region 422 of the second bus member 42 is simultaneously connected to a plurality of negative electrode tabs 32.

In the above structure, the positive electrode lug 31 and the negative electrode lug 32 are arranged at the same end of the winding core 3, the spacing between the positive electrode and the negative electrode is reduced, so that the internal resistance of the cylindrical battery is reduced when the current is conducted, the heat generation amount of the cylindrical battery is reduced when the cylindrical battery is charged and discharged, the requirement of rapid charging and discharging of the cylindrical battery is met, meanwhile, the first converging part 41 and the second converging part 42 are respectively arranged at the same end to converge the positive electrode lug 31 and the negative electrode lug 32, the flattening and related process steps in the full-electrode lug battery are simplified, the wettability of the electrolyte to the battery core is also improved, the production and processing procedures of the cylindrical battery are effectively simplified, and the production and processing efficiency is improved.

In this embodiment, referring to fig. 1, 4 and 5, the cylindrical battery further includes an insulating disc 43 located between the winding core 3 and the top cover 101, the first bus member 41 and the second bus member 42 are embedded on the insulating disc 43 at intervals to form a bus disc 4, the positive electrode connection region 412 and the negative electrode connection region 422 are exposed from the bus disc 4 toward the winding core 3, the post connection region 411 and the housing connection region 421 are exposed from the bus disc 4 toward the top cover 101, and in some embodiments, the insulating disc 43 may be formed by injection molding, that is, the bus disc 4 is a structure formed by integrally molding the first bus member 41, the second bus member 42 and the insulating disc 43 after positioning the first bus member 41 and the second bus member 42.

In the above embodiment, the bus plate 4 is an integral structure, so that the assembly is convenient, and the insulating plate 43 has the functions of positioning and insulating the first bus member 41 and the second bus member 42, so that the first bus member 41 and the second bus member 42 are prevented from being offset and conducting unnecessarily to cause internal short circuit of the battery.

In this embodiment, the post connection area 411 of the first current collecting member 41 and the housing connection area 421 of the second current collecting member 42 are planar areas, a plurality of protruding structures protruding toward the top cover 101 are provided on the post connection area 411 and the housing connection area 421, it is to be understood that the first current collecting member 41 improves the electrical connection quality with the lateral extension 201 of the post 2 through the protruding structures on the post connection area 411, while on the second current collecting member 42, the protruding structures on the housing connection area 421 improve the electrical connection quality between the second current collecting member 42 and the housing 1, specifically, a plurality of groups of protruding areas are provided on the post connection area 411 and the housing connection area 421 at intervals along the circumferential direction of the current collecting disc 4, a connection part is formed between adjacent protruding areas, each group of protruding areas includes a plurality of bosses 401 provided along the radial direction of the current collecting disc 4, the bosses 401 here include, but are not limited to, are profiled bosses 401 such as plum bosses 401, and the profiled bosses 401 are adopted for the purpose of deforming themselves when being pressed to make the bosses 401 adhere to the parts that abut against them as much as possible.

In this embodiment, a conductor block 5 is connected between the inner wall of the top cover 101 of the housing 1 and the second bus member 42, and when the height difference between the housing 1 of the conductor block 5 and the lateral extension 201 of the pole 2 is equal to or smaller than the height difference between the boss 401 and the conductor block 5, the connection portion is welded to the conductor block 5, and in this process, the conductor block 5 serves as an electrical conductive structure between the second bus member 42 and the housing 1 on the one hand, and serves as an intermediate connection structure between the second bus member 42 and the housing 1 on the other hand, where the connection portion and the conductor block 5 are welded in a manner such as laser penetration welding, and the connection portion serves as a welded region, and a welding point or weld is formed on the connection portion.

It will be appreciated that the connection means involved in the connection includes, but is not limited to, bonding, welding, for example, in this embodiment, referring to fig. 6, the connection is an area between the post connection area 411 and the bump structure on the housing connection area 421, the connection means involved in laser penetration welding is such that the first bus member 41 is connected with the lateral extension 201, and the second bus member 42 is connected with the conductor block 5, and the laser penetration welded laser spot 402 is located on the connection portion on the bus plate 4 after welding, and in other embodiments, the strip weld may be formed on the connection portion by other welding means or welding paths.

In this embodiment, referring to fig. 1, the top cover 101 is provided with an insulating member 6, the pole 2 is separated from the housing 1 by the insulating member 6, the insulating member 6 is provided with a mounting hole, and the conductor block 5 is located in the mounting hole and is separated from the pole 2 by the insulating member 6.

In the above embodiments, in some application scenarios, the insulating member 6 may be integrally formed, for example, by injection molding plastic, that is, after the conductor block 5 is positioned at a position between the inner wall of the top cover 101 and the second bus bar member 42, at least part of the space between the housing 1, the bus bar 4 and the pole 2 is injection-filled to form the insulating member 6, so that the insulating member 6 directly forms a mounting hole wrapping the side wall of the conductor block 5 at the position of the conductor block 5, and this way, at the same time, the sealing connection quality between the insulating member 6 and the housing 1 can be ensured, and based on the above embodiments, it is understood that the insulating member 6 herein may also be integrated with the insulating structure between the pole 2 and the top cover 101, and further, in this embodiment, the insulating member 6 also laterally wraps the lateral extension 201 to block the lateral extension 201 from the housing 1, so as to ensure insulation.

In this embodiment, the conductor block 5 and the second bus member 42 are made of copper, the post 2 and the first bus member 41 are made of aluminum, the area of the positive electrode connection region 412 is larger than that of the negative electrode connection region 422, it is worth noting that the positive electrode in the battery generally adopts an aluminum material which is not easily oxidized, a compact oxide film is generated on the surface of the aluminum material, the positive electrode with high potential has a protective effect, the negative electrode generally adopts a copper material with better conductivity, the conductivity of the copper material is better than that of the aluminum material, the area of the positive electrode connection region 412 is set to be larger than that of the negative electrode connection region 422, namely, the overall conductivity of the first bus member 41 is improved, the positive electrode connection region is matched with that of the second bus member 42, and the overall conductivity of the cylindrical battery is balanced, so that the material utilization efficiency in the current conduction process is improved.

Further, in the present embodiment, the positive electrode connection region 412 of the first current collecting member 41 covers the positive electrode tab 31, the negative electrode connection region 422 of the second current collecting member 42 covers the negative electrode tab 32, and the area of the positive electrode tab 31 covered by the positive electrode connection region 412 is larger than the area of the negative electrode tab 32 covered by the negative electrode connection region 422, which is beneficial to further improving the balance of positive and negative electrode current collecting and improving the material utilization efficiency in the current conducting process.

In this embodiment, referring to fig. 3 and 5, the positive tab 31 and the negative tab 32 are led out in the form of multipolar tabs and form a sector area, and the first converging component 41 and the second converging component 42 are sector components, so that the positive connection area 412 and the negative connection area 422 are also sector-shaped, in a cylindrical battery, the adoption of the sector-shaped structure can reduce the area waste, reduce the arrangement area under the same flow guiding capability, and the sectors are relatively regular, thereby being beneficial to improving the design convenience.

Further, the lateral extension 201 is also fan-shaped, which can reduce the area waste of the lateral extension 201, reduce the arrangement area under the same flow guiding capability, and the fan-shape is relatively regular, which is beneficial to improving the design convenience, and the lateral extension 201 covers the pole connection region 411.

In this embodiment, the top cover 101 is integrally formed at the top end of the housing 1, the bottom cover 11 is a cover plate structure mounted at the bottom end of the housing 1 through a connection structure, specifically, referring to fig. 8, the edge of the bottom cover 11 overlaps with the edge of the bottom end of the housing 1, and the overlapped part is rolled up multiple times in one direction to form a winding structure 102, so that on one hand, the packaging efficiency can be improved, the occupied space when the bottom cover 11 is connected with the housing 1 is reduced, on the other hand, such a connection structure can tighten the bottom cover 11 while fixedly connecting the bottom cover 11 with the housing 1, so that the bottom cover 11 is tightly attached to the winding core 3 accommodated in the housing 1 and tightly presses the winding core 3 towards one side of the top cover 101, so that the compactness of each component in the housing 1 is ensured when the first bus member 41 contacts with the housing 1 or the conductor block 5, the contact area between the protruding structure and the housing 1 or the conductor block 5 is ensured, and further the stability of the current conducting path is ensured.

In some embodiments, the bottom cover 11 may be covered on the bottom end of the housing 1 by squatting, for example, in another embodiment, referring to fig. 9, the bottom end of the housing 1 is bent to clamp the bottom cover 11, and a sealing ring 111 is further disposed at a position where the edge of the bottom cover 11 is clamped by the bent housing 1.

In one embodiment, the present utility model also provides a battery module including a case, and a plurality of cylindrical batteries as shown in the foregoing embodiments accommodated in the case.

As described above, in the cylindrical battery and the battery module provided in the exemplary embodiments of the present utility model, the positive electrode tab 31 and the negative electrode tab 32 are disposed at the same end of the winding core 3, so that the interval between the positive electrode and the negative electrode is reduced, thereby reducing the internal resistance of the cylindrical battery when the current is conducted, being beneficial to reducing the heat generated when the cylindrical battery is charged and discharged, being beneficial to meeting the requirement of rapid charging and discharging of the cylindrical battery, and simultaneously, the first converging component 41 and the second converging component 42 are disposed at the same end to converge the positive electrode tab 31 and the negative electrode tab 32, thereby simplifying the flattening and related process steps in the full-tab battery, improving the wettability of the electrolyte to the battery core, effectively simplifying the production and processing procedures of the cylindrical battery, and being beneficial to improving the production and processing efficiency.

The above embodiments are merely illustrative of the principles of the present utility model and its effectiveness, and are not intended to limit the utility model. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the utility model. Accordingly, it is intended that all equivalent modifications and variations of the utility model be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (14)

1. A cylindrical battery, comprising:

the shell is cylindrical, and the two ends of the shell are covered with a top cover and a bottom cover;

the winding core is arranged in the shell, and one end of the winding core, which faces the top cover, is led out with a positive electrode lug and a negative electrode lug;

the pole is arranged on the top cover of the shell and is arranged between the pole and the top cover in an insulating way;

the first confluence part is arranged between the winding core and the top cover in an insulating way and comprises a positive electrode connection area electrically connected with the positive electrode lug and a pole connection area electrically connected with the pole;

the second confluence part is arranged between the winding core and the top cover and comprises a negative electrode connection area electrically connected with the negative electrode lug and a shell connection area directly or indirectly electrically connected with the shell towards one side of the top cover;

the pole extends laterally towards the pole connection region to form a lateral extension, and the lateral extension is electrically connected with the pole connection region.

2. The cylindrical battery of claim 1, further comprising an insulating disk between the winding core and the top cover, wherein the first bus member and the second bus member are alternately embedded in the insulating disk to form a bus disk, the post connection region and the case connection region are exposed from the bus disk toward the top cover side, and the positive connection region and the negative connection region are exposed from the bus disk toward the winding core.

3. The cylindrical battery of claim 2, wherein: the pole connection region and the housing connection region are provided with a plurality of protruding structures facing the top cover.

4. A cylindrical battery according to claim 3, wherein: the pole connection area and the shell connection area are provided with a plurality of groups of protruding areas at intervals along the circumferential direction of the bus plate, connecting portions are formed between adjacent protruding areas, and each group of protruding areas comprises a plurality of bosses arranged along the radial direction of the bus plate.

5. The cylindrical battery of claim 4, wherein: and a conductor block is connected between the inner wall of the top cover of the shell and the second converging component.

6. The cylindrical battery according to claim 5, wherein: the boss is abutted on the conductor block, and the connecting part is welded with the conductor block.

7. The cylindrical battery of claim 6, wherein: the top cover is provided with an insulating part, the pole is separated from the shell through the insulating part, the insulating part is provided with a mounting hole, and the conductor block is positioned in the mounting hole and is separated from the pole through the insulating part.

8. The cylindrical battery according to claim 5, wherein: the conductor block and the second confluence part are made of copper, the pole column and the first confluence part are made of aluminum, and the area of the positive electrode connection area is larger than that of the negative electrode connection area.

9. The cylindrical battery of claim 6, wherein: the positive electrode connection region of the first bus member covers the positive electrode tab, the negative electrode connection region of the second bus member covers the negative electrode tab, and the area of the positive electrode tab covered by the positive electrode connection region is larger than the area of the negative electrode tab covered by the negative electrode connection region.

10. A cylindrical battery according to any one of claims 1-9, wherein: the positive electrode lug and the negative electrode lug are respectively led out to be sector areas in the form of multipolar lugs.

11. The cylindrical battery of claim 10, wherein: the first converging part and the second converging part are in a fan-shaped structure, and the positive electrode connecting area and the negative electrode connecting area are fan-shaped.

12. The cylindrical battery of claim 11, wherein: the lateral extension is fan-shaped and covers the pole connection region.

13. The cylindrical battery of claim 1, wherein: the top cover is integrally formed at the top end of the shell, and the edge of the bottom cover is overlapped with the edge of the bottom end of the shell and is rolled to form a winding structure.

14. A battery module, comprising: a case, and a plurality of cylindrical batteries as claimed in any one of claims 1 to 13 housed in the case.