CN219393644U - Cylindrical battery and battery pack - Google Patents

Abstract

The disclosure provides a cylindrical battery and battery package relates to battery technology field. The cylindrical battery comprises a battery core body and a plurality of electrode lugs, wherein the battery core body comprises a plurality of layers of wound electrode plates, and the number of winding layers of the electrode plates is M; each layer of pole piece is provided with at least one pole lug; the electrode lug is positioned on the end face of the battery cell body; the terminal surface of electric core body includes a plurality of sub-tab areas, and every sub-tab area has N utmost point ear, and N is less than M. The cylindrical battery has a larger overcurrent area, is convenient for bending the lug, ensures that the lug and the adapter are reliably connected, and improves the energy density of the cylindrical battery by optimizing the distribution of the lug.

Description

Cylindrical battery and battery pack

Technical Field

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

Background

At present, the number of layers of battery cells is increased, the number of layers of tabs of a cathode or an anode is increased relatively, and for the existing cylindrical battery, the more the number of winding layers of the winding core is, the more the number of layers of tabs is, and the tabs need to be bent when connecting the switching sheets. In the prior art, the lugs of the whole battery are bent at the same time, in other words, the lugs of the positive pole pieces of all layers are bent at the same time, or the lugs of the negative pole pieces of all layers are bent at the same time, the more the number of winding layers of the battery core is, the larger the stress of the lugs is when the lugs are bent, and the more difficult the peripheral lugs are to bend. Meanwhile, the more the number of winding layers of the battery cell is, the higher the thickness of a bending structure formed by the electrode lugs is after the electrode lugs are bent, and when the battery cell is assembled in the battery shell, the thicker the bending structure of the electrode lugs is, the more the internal space of the battery shell is wasted, and the battery energy density is also reduced.

Disclosure of Invention

The utility model aims to provide a cylindrical battery and a battery pack, which can facilitate forming a bending structure of a tab, reduce bending stress, improve energy density of the cylindrical battery and improve product quality of the whole battery pack.

Embodiments of the present utility model are implemented as follows:

in a first aspect, the present utility model provides a cylindrical battery comprising:

the battery cell comprises a battery cell body, wherein the battery cell body comprises a plurality of layers of wound pole pieces, and the winding layer number of the pole pieces is M;

the pole pieces are provided with at least one pole lug in each layer; the electrode lugs are positioned on the end face of the battery cell body; the end face of the battery cell body comprises a plurality of sub-tab areas, each sub-tab area is provided with N tabs, and N is smaller than M.

In an alternative embodiment, a plurality of tabs in each sub-tab region are disposed along a radial direction of the cell body.

In an alternative embodiment, in each sub-tab area, in two pole pieces where two radially adjacent tabs are located, the number of layers of the two pole pieces differs by 1 or more.

In an alternative embodiment, the tab includes a bending portion extending toward the center or edge of the cell body along the radial direction of the cell body.

In an alternative embodiment, the lug near the core of the cell body is bent along the radial direction towards the direction away from the center; the electrode lug close to the edge of the battery cell body is bent along the radial direction towards the direction close to the center.

In an alternative embodiment, the density of the tabs near the edge of the cell body is greater than the density of the tabs near the center of the cell body.

In an alternative embodiment, the end face of the battery cell body includes a first end face and a second end face that are disposed opposite to each other, and the first end face and the second end face are formed with a plurality of sub-tab areas respectively.

In an alternative embodiment, the end face of the battery cell body includes a first end face and a second end face that are disposed opposite to each other, and a plurality of sub-tab areas are formed on the first end face or the second end face.

In an alternative embodiment, a plurality of the sub-tab regions are uniformly distributed in the circumferential direction.

In a second aspect, the present utility model provides a battery pack comprising a tab and a plurality of cylindrical batteries as in any of the previous embodiments, the tab being electrically connected to the tab.

The beneficial effects of the embodiment of the utility model include:

according to the cylindrical battery provided by the embodiment of the utility model, each layer of pole piece is provided with at least one tab, so that the overcurrent area can be increased, each layer of pole piece is ensured to be electrically connected with the adapter piece, the connection is reliable, and the stability is better. All the tabs are arranged in a plurality of sub-tab areas, the number N of the tabs in a single sub-tab area is smaller than the number M of winding layers of the pole pieces, so that the tabs are bent in each sub-tab area, bending stress can be reduced, the bending structure is more convenient, and the bending space is more and more flexible. And secondly, the thickness of the bending structure formed by the lugs in each sub-lug area is smaller, and the occupied internal space of the shell is smaller, so that the energy density of the battery is improved. The smaller the thickness of the bending structure is, the more convenient and reliable the welding of the tab and the switching piece is, the false welding is avoided, the welding quality is improved, and the product quality of the battery pack is further improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

Fig. 1 is a schematic structural view of a cylindrical battery according to an embodiment of the present utility model;

fig. 2 is a schematic distribution diagram of tabs of a cylindrical battery according to an embodiment of the present utility model.

Icon: 100-cylindrical batteries; 110-a cell body; 111-a first end face; 120-electrode lugs; 130-sub-tab area.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present utility model more apparent, the technical solutions of the embodiments of the present utility model will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present utility model, and it is apparent that the described embodiments are some embodiments of the present utility model, but not all embodiments of the present utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by those skilled in the art based on the embodiments of the utility model without making any inventive effort, are intended to be within the scope of the utility model.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present utility model, it should be noted that, directions or positional relationships indicated by terms such as "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., are directions or positional relationships based on those shown in the drawings, or are directions or positional relationships conventionally put in use of the inventive product, are merely for convenience of describing the present utility model and simplifying the description, and are not indicative or implying that the apparatus or element to be referred to must have a specific direction, be constructed and operated in a specific direction, and thus should not be construed as limiting the present utility model. Furthermore, the terms "first," "second," "third," and the like are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

Furthermore, the terms "horizontal," "vertical," and the like do not denote a requirement that the component be absolutely horizontal or overhang, but rather may be slightly inclined. As "horizontal" merely means that its direction is more horizontal than "vertical", and does not mean that the structure must be perfectly horizontal, but may be slightly inclined.

In the description of the present utility model, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present utility model will be understood in specific cases by those of ordinary skill in the art.

At present, the number of layers of battery cells is increased, the number of layers of tabs of a cathode or an anode is increased relatively, and for the existing cylindrical battery, the more the number of winding layers of the winding core is, the more the number of layers of tabs is, and the tabs need to be bent when connecting the switching sheets. In the prior art, the lugs of the whole battery are bent at the same time, in other words, the lugs of the positive pole pieces of all layers are bent at the same time, or the lugs of the negative pole pieces of all layers are bent at the same time, the more the number of winding layers of the battery core is, the larger the stress of the lugs is when the lugs are bent, and the more difficult the peripheral lugs are to bend. Meanwhile, the more the number of winding layers of the battery cell is, the higher the thickness of a bending structure formed by the electrode lugs is after the electrode lugs are bent, and when the battery cell is assembled in the battery shell, the thicker the bending structure of the electrode lugs is, the more the internal space of the battery shell is wasted, and the battery energy density is also reduced.

In order to overcome at least one defect of the prior art, the embodiment of the utility model provides a cylindrical battery, which can optimize the distribution of the tabs, facilitate the bending of the tabs, reduce bending stress, reduce the thickness of a bending structure, reduce the waste of the inner space of a shell and improve the energy density of the cylindrical battery.

Referring to fig. 1 and fig. 2, a cylindrical battery 100 provided by an embodiment of the present utility model includes a battery core body 110 and a plurality of tabs 120, where the battery core body 110 includes a plurality of layers of wound pole pieces, and the number of winding layers of the pole pieces is M; each layer of pole piece is provided with at least one pole lug 120; the tab 120 is located at the end face of the battery core body 110; the end face of the battery cell body 110 includes a plurality of sub-tab regions 130, each sub-tab region 130 has N tabs 120, where N is less than M. The cylindrical battery 100 has a larger overcurrent area, is convenient for bending the lug 120, ensures reliable connection between the lug 120 and the adapter, reduces the thickness of the bending structure of the lug 120 by optimizing the distribution of the lug 120, saves the space inside the shell, and improves the energy density of the cylindrical battery 100.

Optionally, a plurality of tabs 120 in each sub-tab region 130 are disposed along a radial direction of the cell body 110. In this embodiment, each sub-tab region 130 is a sector region formed by two radii of the end surface of the cell body 110. The number of sub-tab regions 130 may be any natural number greater than or equal to 2, such as two, three, four, five, eight, ten, fifteen, twenty or more, and is not particularly limited herein. As shown in fig. 1, the end face is provided with eight sub-tab regions 130. As shown in fig. 2, the end face is provided with seven sub-tab regions 130. Each sub-tab region 130 has at least one tab 120. The tab 120 may be distributed identically or differently in different sub-tab regions 130.

Optionally, in each sub-tab area 130, in two pole pieces where two radially adjacent tabs 120 are located, the number of layers of the two pole pieces differs by 1 or more. As shown in fig. 1, the tabs 120 in each sub-tab region 130 are continuously distributed, that is, the number of layers of two pole pieces in which two radially adjacent tabs 120 are located differ by 1. For example, in a certain sub-tab area 130, in a direction from inside to outside (from center to edge) along a radial direction, the number of pole pieces where the first tab 120 is located is 10 th, and the number of pole pieces where the second tab 120 is located is 11 th, so that the first tab 120 and the second tab 120 are continuously distributed.

In some embodiments, the tabs 120 in each sub-tab region 130 may be spaced apart, that is, the number of layers of two pole pieces in which two radially adjacent tabs 120 are located differ by more than 1, and the number of layers of the two pole pieces may be any number greater than or equal to 2. For example, in a certain sub-tab area 130, in a direction from inside to outside (from center to edge) along a radial direction, the number of pole pieces where the first tab 120 is located is 10 th, and the number of pole pieces where the second tab 120 is located is 15 th, so that the first tab 120 and the second tab 120 are distributed at intervals.

It is easy to understand that in the same sub-tab region 130, the tabs 120 in the region may be all continuously distributed, or the tabs 120 in the region may be all distributed at intervals; alternatively, some of the tabs 120 are continuously distributed in the region and some of the tabs 120 are spaced apart. For example, in the sub-tab region 130, the tabs 120 are continuously distributed from layer 1 to layer 20; the pole pieces are distributed at intervals or are not arranged from the 21 st layer to the 40 th layer, and the pole lugs 120 are distributed at intervals or are not arranged at intervals; the pole pieces are continuously distributed from the 41 st layer to the 65 th layer, and the pole lugs 120. Of course, other distribution methods are also possible, and are not particularly limited herein. In each sub-tab region 130, the number of distributions, the positions of the distributions, the distribution manner (continuous or intermittent), and the like of the tabs 120 may be flexibly set.

It should be noted that, the tabs 120 are distributed at intervals, so that bending stress of the tabs 120 can be properly reduced, bending space is larger, bending direction is more flexible, and the tabs can be bent inwards or outwards.

Optionally, the tab 120 includes a bending portion, and the bending portion extends toward the center or the edge of the cell body 110 along the radial direction of the cell body 110. For each tab 120, the bending direction of the tab 120 can be flexibly selected according to the specific position of the tab 120 and the spatial position near the tab 120. For example, the tab 120 near the center of the cell body 110 is bent along the radial direction in a direction away from the center, i.e. is bent outwards; the tab 120 near the edge of the cell body 110 is bent in a radial direction toward the center, i.e., is bent inward. Therefore, the space inside the shell can be reasonably utilized, and the waste of the space inside the battery shell is reduced.

Optionally, the density of the tabs 120 near the edge of the cell body 110 is greater than the density of the tabs 120 near the center of the cell body 110. In other words, the closer to the edge of the cell body 110, the more the radius is, the more the distribution space is relatively sufficient, and the more the tabs 120 are distributed, the fewer the number of the tabs 120 are distributed at the position closer to the center of the cell body 110.

In this embodiment, the portion near the center of the cell body 110 is understood to be a region within approximately the center third of the radius of the end face of the cell body 110. The portion near the edge of the cell body 110 can be understood as an area within about one third of the near edge of the radius of the end face of the cell body 110. Assuming that the radius of the end surface of the cell body 110 is 15cm, a circular area having a radius of about 5cm belongs to a portion near the center. The annular region formed within a radius of 15cm and having a radius of 10cm or more belongs to a region near the edge. Alternatively, assuming that the number of winding layers of the pole piece of the cylindrical battery 100 is 300, the tabs 120 located approximately between the 1 st layer and the 100 th layer belong to the tabs 120 near the center of the battery cell body 110, the number of the tabs 120 distributed is smaller, and the tabs 120 can be bent outwards. The tabs 120 located between the 201 st layer and the 300 nd layer belong to tabs 120 near the edge of the cell body 110, and the number of the tabs 120 distributed is greater, and the bending direction can be inwards bent.

Optionally, the end surface of the battery core body 110 includes a first end surface 111 and a second end surface that are disposed opposite to each other, where the first end surface 111 and the second end surface are formed with a plurality of sub-tab areas 130 respectively. I.e., the cylindrical battery 100 is of a structure of the double-sided tab 120. Alternatively, in some embodiments, the first end face 111 or the second end face is formed with a plurality of sub-tab regions 130. The tab 120 is formed only on one end face, and belongs to the structure of the single-side tab 120.

Alternatively, the plurality of sub-tab regions 130 are uniformly distributed in the circumferential direction. By adopting uniform distribution, the space can be fully utilized, the space waste is reduced, the bending of the tab 120 is facilitated, the bending stress is reduced, and the bending direction is flexible. The welding of the tab 120 and the switching piece is facilitated, the cold joint is avoided, and the welding quality and efficiency are improved. Secondly, the overall thickness of the bent structure of the tab 120 is smaller after bending, which occupies less space and is beneficial to improving the energy density of the cylindrical battery 100. Of course, in other embodiments, the plurality of sub-tab areas 130 may be unevenly distributed in the circumferential direction, and may be flexibly disposed, which is not particularly limited herein.

The battery pack provided by the embodiment of the utility model comprises a switching sheet and a plurality of cylindrical batteries 100 according to any one of the previous embodiments, wherein the switching sheet is electrically connected with the tab 120. In this embodiment, the tab and tab 120 are welded. After the tabs 120 are bent, the bending part of each tab 120 is welded with the adapter plate, so as to realize electrical connection. Because each layer of pole piece is provided with at least one tab 120, each layer of pole piece can be ensured to be respectively and electrically connected with the switching piece, and the overcurrent area is increased. Through the optimized distribution setting to the tab 120, reduce the bending stress of tab 120, reduce the thickness of buckling structure, avoid the cold joint in the welding process, improve welding quality, and then improve the product quality of whole battery package. In addition, the thickness of the bending structure after the tab 120 is bent is smaller, the occupied space is small, the waste of the space in the shell is reduced, and the energy density of the cylindrical battery 100 is improved.

In summary, the cylindrical battery 100 and the battery pack provided by the embodiments of the present utility model have the following advantages, including:

according to the cylindrical battery 100 and the battery pack provided by the embodiment of the utility model, each layer of pole piece is provided with at least one tab 120, so that the overcurrent area can be increased, the electric connection between each layer of pole piece and the adapter piece is ensured, the connection is reliable, and the stability is better. All the tabs 120 are respectively arranged in a plurality of sub-tab areas 130, and the number N of the tabs 120 in a single sub-tab area 130 is smaller than the number M of winding layers of the pole pieces, so that the tabs 120 are bent in each sub-tab area 130, bending stress can be reduced, the bending structure is more convenient, and the bending direction is more flexible and more space can be bent. Secondly, the thickness of the bending structure formed by the tab 120 in each sub-tab region 130 is smaller, and the occupied internal space of the housing is smaller, which is beneficial to improving the energy density of the battery. The smaller the thickness of the bending structure is, the more convenient and reliable the welding between the tab 120 and the switching piece is, the false welding is avoided, the welding quality is improved, and the product quality of the battery pack is further improved.

The above description is only of the preferred embodiments of the present utility model and is not intended to limit the present utility model, but various modifications and variations can be made to the present utility model by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present utility model should be included in the protection scope of the present utility model.

Claims (10)

1. A cylindrical battery, comprising:

the battery cell comprises a battery cell body, wherein the battery cell body comprises a plurality of layers of wound pole pieces, and the winding layer number of the pole pieces is M;

the pole pieces are provided with at least one pole lug in each layer; the electrode lugs are positioned on the end face of the battery cell body; the end face of the battery cell body comprises a plurality of sub-tab areas, each sub-tab area is provided with N tabs, and N is smaller than M.

2. The cylindrical battery of claim 1, wherein a plurality of the tabs in each of the sub-tab regions are disposed along a radial direction of the cell body.

3. The cylindrical battery according to claim 2, wherein in each of the sub-tab regions, the number of layers of two of the pole pieces in which two radially adjacent tabs are located differ by 1 or more than 1.

4. The cylindrical battery of claim 1, wherein the tab includes a bent portion extending toward a center or edge of the cell body in a radial direction of the cell body.

5. The cylindrical battery according to claim 4, wherein the bent portion is bent in a direction away from the center in a radial direction near the tab of the core body; the electrode lug close to the edge of the battery cell body is bent along the radial direction towards the direction close to the center.

6. The cylindrical battery of claim 4, wherein the density of tabs near the edge of the cell body is greater than the density of tabs near the center of the cell body.

7. The cylindrical battery of claim 1, wherein the end face of the cell body comprises a first end face and a second end face disposed opposite to each other, the first end face and the second end face being formed with a plurality of the sub-tab regions, respectively.

8. The cylindrical battery of claim 1, wherein the end face of the cell body comprises a first end face and a second end face disposed opposite to each other, the first end face or the second end face being formed with a plurality of the sub-tab regions.

9. The cylindrical battery according to any one of claims 1 to 8, wherein a plurality of the sub-tab regions are uniformly distributed in a circumferential direction.

10. A battery pack comprising a tab and a plurality of cylindrical batteries as claimed in any one of claims 1 to 9, the tab being electrically connected to the tab.