CN219419459U - Cylindrical battery - Google Patents

Abstract

The disclosure relates to the technical field of batteries, and discloses a cylindrical battery; the cylindrical battery includes a winding structure, a first insulating film, and a second insulating film; the winding structure comprises a body part and a lug part which are connected with each other, wherein the lug part is positioned on at least one side of the body part in a first direction, and the first direction is parallel to the axial direction of the cylindrical battery; the first insulating film is arranged on the circumferential outer surface of the winding structure and covers at least part of the lug part and part of the body part; the second insulating film is arranged on the circumferential outer surface of the winding structure, covers at least part of the body part, and has a ratio of the width of the first insulating film to the width of the second insulating film in the first direction of 0.05 to 0.4. This cylindrical battery improves the assembly efficiency of second insulating film, guarantees the assembly yield of second insulating film moreover, and first insulating film is great with winding structure's connection area, joint strength is higher, be difficult for inefficacy, guarantees the insulating effect between winding structure and the shell.

Description

Cylindrical battery

Technical Field

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

Background

The lithium ion power battery with the advantages of high energy density, long cycle life, green pollution-free and the like becomes one of the necessary choices of future industry because the original energy consumption structure is gradually changed and the energy is more reasonably and effectively utilized.

However, the insulating film of the current cylindrical battery is difficult to assemble.

It should be noted that the information disclosed in the above background section is only for enhancing understanding of the background of the present disclosure and thus may include information that does not constitute prior art known to those of ordinary skill in the art.

Disclosure of Invention

The present disclosure aims to overcome the defect of the above related art that the assembly difficulty of the insulating film is relatively high, and provide a cylindrical battery with a relatively low assembly difficulty of the insulating film.

According to one aspect of the present disclosure, there is provided a cylindrical battery including:

a winding structure including a body portion and a tab portion connected to each other, the tab portion being located on at least one side of a first direction of the body portion, the first direction being parallel to an axial direction of the cylindrical battery;

a first insulating film provided on a circumferential outer surface of the winding structure and covering at least a part of the tab portion and a part of the body portion;

and a second insulating film provided on the circumferential outer surface of the winding structure, the second insulating film covering at least a portion of the body portion, wherein a ratio of a width of the first insulating film to a width of the second insulating film in the first direction is 0.05 or more and 0.4 or less.

The width of the first insulating film is greater than or equal to 0.05 and less than or equal to 0.4, namely the width of the first insulating film in the first direction is increased, the width of the second insulating film in the first direction is reduced, on one hand, the second insulating film is not easy to wrinkle when being installed, so that the assembly efficiency of the second insulating film is improved, the assembly yield of the second insulating film is ensured, and the yield of the cylindrical battery is ensured. On the other hand, the width of the first insulating film is wider, and the connection area with the winding structure is larger, so that the connection strength between the first insulating film and the winding structure is higher, the failure is not easy to occur, and the insulation effect between the winding structure and the shell is ensured.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the disclosure.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the disclosure and together with the description, serve to explain the principles of the disclosure. It will be apparent to those of ordinary skill in the art that the drawings in the following description are merely examples of the disclosure and that other drawings may be derived from them without undue effort.

Fig. 1 is a perspective schematic view of an example embodiment of a cylindrical battery of the present disclosure.

Fig. 2 is a schematic cross-sectional view of a first example embodiment of a cylindrical battery of the present disclosure.

Fig. 3 is a schematic cross-sectional view of a second example embodiment of a cylindrical battery of the present disclosure.

Fig. 4 is a schematic cross-sectional view of a third example embodiment of a cylindrical battery of the present disclosure.

Fig. 5 is a schematic structural view of the insulating member in fig. 2-3.

Reference numerals illustrate:

1. a housing; 11. a top plate; 12. a bottom plate; 13. a side plate;

2. a winding structure; 21. a body portion; 211. a first end face; 212. a second end face; 22. a tab portion; 221. a first tab; 222. a second lug;

31. a first insulating film; 32. a second insulating film;

4. an insulating member; 41. an insulating body portion; 42. a limit part; 421. a groove;

51. a positive electrode post; 52. a negative electrode column;

6. a collecting tray;

x, first direction.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus detailed descriptions thereof will be omitted. Furthermore, the drawings are merely schematic illustrations of the present disclosure and are not necessarily drawn to scale.

Although relative terms such as "upper" and "lower" are used in this specification to describe the relative relationship of one component of an icon to another component, these terms are used in this specification for convenience only, such as in terms of the orientation of the examples described in the figures. It will be appreciated that if the device of the icon is flipped upside down, the recited "up" component will become the "down" component. When a structure is "on" another structure, it may mean that the structure is integrally formed with the other structure, or that the structure is "directly" disposed on the other structure, or that the structure is "indirectly" disposed on the other structure through another structure.

The terms "a," "an," "the," "said" and "at least one" are used to indicate the presence of one or more elements/components/etc.; the terms "comprising" and "having" are intended to be inclusive and mean that there may be additional elements/components/etc. in addition to the listed elements/components/etc.; the terms "first," "second," and "third," etc. are used merely as labels, and do not limit the number of their objects.

In the present application, unless explicitly specified and limited otherwise, the term "coupled" is to be construed broadly, and for example, "coupled" may be either fixedly coupled, detachably coupled, or integrally formed; can be directly connected or indirectly connected through an intermediate medium. "and/or" is merely an association relationship describing an association object, and means that three relationships may exist, for example, a and/or B may mean: a exists alone, A and B exist together, and B exists alone. In addition, the character "/" herein generally indicates that the front and rear associated objects are an "or" relationship.

The present disclosure provides a cylindrical battery, which may include a winding structure 2, a first insulating film 31, and a second insulating film 32, as shown with reference to fig. 1 to 4; the winding structure 2 may include a body portion 21 and a tab portion 22 connected to each other, the tab portion 22 being located on at least one side of the body portion 21 in a first direction X, the first direction X being parallel to an axial direction of the cylindrical battery; the first insulating film 31 is provided on the circumferential outer surface of the winding structure 2, and covers at least part of the tab portion 22 and part of the body portion 21; the second insulating film 32 is provided on the circumferential outer surface of the winding structure 2, the second insulating film 32 covers at least part of the body portion 21, and a ratio of a width of the first insulating film 31 to a width of the second insulating film 32 in the first direction X is 0.05 or more and 0.4 or less.

The cylindrical battery of this disclosure, on the one hand, reduces the width of second insulating film 32 in first direction X for second insulating film 32 is difficult to wrinkle in the time of the installation, in order to improve the assembly efficiency of second insulating film 32, guarantees the assembly yield of second insulating film 32 moreover, in order to guarantee the yield of cylindrical battery. On the other hand, the width of the first insulating film 31 in the first direction X is increased, so that the width of the first insulating film 31 is wider, the connection area with the winding structure 2 is larger, the connection strength between the first insulating film 31 and the winding structure 2 is higher, failure is not easy to occur, and the insulating effect between the winding structure 2 and the housing 1 is ensured.

In the present exemplary embodiment, referring to fig. 1, the cylindrical battery may include a case 1, the case 1 may be provided as a cylinder, that is, the case 1 may include two end plates disposed opposite to each other, the two end plates being a top plate 11 and a bottom plate 12, respectively, the top plate 11 and the bottom plate 12 being each provided as a circular plate, a side plate 13 being connected between the top plate 11 and the bottom plate 12, the side plate 13 being provided as a cylinder. The side plates 13, the top plate 11 and the bottom plate 12 surround the accommodation chamber forming a cylindrical battery.

A battery cell and an electrolyte are arranged in the housing 1, and the battery cell can comprise a winding structure 2 and an insulating film at least coated on the circumferential outer surface of the winding structure 2.

Referring to fig. 2-4, the winding structure 2 may include a body portion 21 and a tab portion 22. The coiled structure 2 is coiled such that the coiled structure 2 forms a generally cylindrical structure; that is, the body portion 21 has a substantially cylindrical structure, the body portion 21 has a first end surface 211 and a second end surface 212 which are disposed opposite to each other, the first end surface 211 and the second end surface 212 are disposed substantially in parallel, and the first end surface 211 and the second end surface 212 are disposed substantially in parallel with two end plates (the top plate 11 and the bottom plate 12) of the housing 1.

The winding structure 2 may be a unit formed by winding a laminated structure, and the laminated structure may include a first electrode sheet, a separator, and a second electrode sheet, which are laminated in this order, and when the first electrode sheet is a positive electrode sheet, the second electrode sheet is a negative electrode sheet. Namely, the first pole piece, the second pole piece opposite to the first pole piece and the isolating film arranged between the first pole piece and the second pole piece are coiled to obtain a coiled coiling structure 2. Of course, the polarities of the first pole piece and the second pole piece may be interchanged, i.e. the first pole piece may be a negative pole piece and the second pole piece may be a positive pole piece. The first and second pole pieces are coated with an active substance. The following description will take the first pole piece as the positive pole piece and the second pole piece as the negative pole piece as an example.

The circumferential outer surface of the winding structure 2 refers to a substantially cylindrical outer surface of the winding structure 2.

Referring to fig. 2 and 3, the tab portion 22 may include a first tab 221 and a second tab 222, and the first tab 221 and the second tab 222 may extend from opposite sides of the body portion 21 of the winding structure 2. Of course, in some example embodiments of the present disclosure, referring to fig. 4, the first tab 221 and the second tab 222 may extend from the same side of the body portion 21 of the winding structure 2.

The tab portion 22 is a conductive foil region where no active material coating is provided, that is, the first tab 221 and the second tab 222 are not coated with an active material coating, and the tab portion 22 is a current collecting layer for transmitting current.

The insulating film is at least coated on the circumferential outer surface of the winding structure 2, that is, the insulating film is at least coated on the outer surface of the winding structure 2, which is approximately cylindrical. If the insulating film is provided as at least two parts provided separately, the two parts are a first insulating film 31 and a second insulating film 32, respectively, the first insulating film 31 being used only for covering the body portion 21, and the second insulating film 32 being used only for covering the tab portion 22; since the tab portion 22 is small in height in the first direction X, the width of the first insulating film 31 in the first direction X is also small; since the height of the body 21 in the first direction X is large, the width of the second insulating film 32 in the first direction X is also large, and the second insulating film 32 having a large width is easily wrinkled at the time of mounting, resulting in a poor mounting efficiency of the second insulating film 32 and a low yield after mounting. Moreover, the connection area between the first insulating film 31 with a narrower width and the winding structure 2 is smaller, which results in lower connection strength between the first insulating film 31 and the winding structure 2 and easy failure, and further results in the first insulating film 31 falling off, which affects the insulation effect between the winding structure 2 and the housing 1.

In order to solve the above-described technical problem, the first insulating film 31 is provided on the circumferential outer surface of the winding structure 2, specifically, the first insulating film 31 covers at least part of the tab portion 22 and part of the body portion 21, that is, the first insulating film 31 covers not only at least part of the tab portion 22 but also part of the body portion 21 near the tab portion 22.

While the second insulating film 32 is also provided on the circumferential outer surface of the winding structure 2, and the second insulating film 32 is located on one side of the first insulating film 31 in the first direction X, specifically, the second insulating film 32 covers at least part of the body portion 21 such that the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 in the first direction X is 0.05 or more and 0.4 or less, for example, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 may be 0.08, 0.14, 0.17, 0.19, 0.22, 0.27, 0.31, 0.38, or the like; further, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 is 0.1 or more and 0.2 or less. That is, the width of the first insulating film 31 in the first direction X is increased, and the width of the second insulating film 32 in the first direction X is decreased.

So set up for second insulating film 32 is difficult to the wrinkle in the time of the installation, in order to improve the assembly efficiency of second insulating film 32, guarantee the assembly yield of second insulating film 32 moreover, in order to guarantee the yield of cylinder battery. Moreover, the width of the first insulating film 31 is wider, and the connection area with the winding structure 2 is larger, so that the connection strength between the first insulating film 31 and the winding structure 2 is higher, failure is not easy to occur, and the insulating effect between the winding structure 2 and the housing 1 is ensured.

Referring to fig. 2 and 3, the first tab 221 and the second tab 222 may extend from opposite sides of the body portion 21 of the winding structure 2.

The first tab 221 is connected to the body portion 21, specifically, the first tab 221 is connected to the first pole piece, and the first tab 221 is located on a side of the first end surface 211 facing away from the body portion 21; a part of the first pole piece extends to protrude from the body portion 21, and is bent to a side of the first end surface 211 away from the body portion 21 to form a first pole ear 221; in this case, the first tab 221 may cover the first end surface 211 entirely, or may cover a part of the first end surface 211.

The second tab 222 is connected to the body portion 21, specifically, the second tab 222 is connected to the second plate, and the second tab 222 is located on a side of the second end surface 212 facing away from the body portion 21, and may be a portion of the second plate extending to protrude from the body portion 21, and is bent to a side of the second end surface 212 facing away from the body portion 21 to form the second tab 222; in this case, the second tab 222 may cover the second end surface 212 entirely or may cover a part of the second end surface 212.

Of course, the first tab 221 may be connected to the second tab, and the second tab 222 may be connected to the first pole piece.

In this case, in the first direction X, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 is 0.15 or more and 0.35 or less, for example, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 may be 0.17, 0.19, 0.22, 0.27, 0.31, or the like.

The first insulating film 31 is for covering a side surface of the first tab 221 near the side plate 13 and a portion of the body portion 21 near the first tab 221. The second insulating film 32 is used to cover a portion of the body portion 21 facing away from the first tab 221 and a side surface of the second tab 222 adjacent to the side plate 13. Therefore, in the first direction X, the width of the first insulating film 31 and the width of the second insulating film 32 can be closer. The connection areas of the first insulating film 31 and the second insulating film 32 and the winding structure 2 are closer, so that the connection strength of the first insulating film 31 and the second insulating film 32 and the winding structure 2 is ensured, and the insulation effect between the winding structure 2 and the shell 1 is ensured; moreover, the widths of the first insulating film 31 and the second insulating film 32 are not too large, so that the first insulating film 31 and the second insulating film 32 are not easy to wrinkle when being mounted, the assembly efficiency of the first insulating film 31 and the second insulating film 32 is improved, and the assembly yield of the cylindrical battery is ensured.

Referring to fig. 2, neither the first tab 221 nor the second tab 222 is electrically connected to the case 1, for example, a first through hole may be provided in the top plate 11 of the case 1, the cylindrical battery may further include a positive electrode post 51 penetrating the first through hole, and the positive electrode post 51 may be connected to the first tab 221 to form a positive electrode of the cylindrical battery.

A second through hole may be provided on the bottom plate 12 of the housing 1, and the cylindrical battery may further include a negative electrode post 52, where the negative electrode post 52 penetrates through the second through hole, and the negative electrode post 52 may be connected with the second tab 222 to form a negative electrode of the cylindrical battery.

Referring to fig. 3, it is also possible that the first tab 221 or the second tab 222 is electrically connected to the housing 1, that is, one of the first tab 221 and the second tab 222 is electrically connected to the housing 1, and the other is not electrically connected to the housing 1; for example, a first through hole may be provided on the top plate 11 of the housing 1, and the cylindrical battery may further include a positive electrode post 51, the positive electrode post 51 penetrating through the first through hole, and the positive electrode post 51 may be connected with the first tab 221 to form a positive electrode of the cylindrical battery. While the second tab 222 is connected to the housing 1 to form the negative electrode of the cylindrical battery, and in particular, the second tab 222 is connected to the bottom plate 12 to form the negative electrode of the cylindrical battery.

Referring to fig. 4, the first tab 221 and the second tab 222 may extend from the same side of the body portion 21 of the winding structure 2.

The first tab 221 is connected to the body portion 21, specifically, the first tab 221 is connected to the first pole piece, and the first tab 221 is located on a side of the first end surface 211 facing away from the body portion 21; a part of the first pole piece extends to protrude from the body portion 21, and is bent to a side of the first end surface 211 away from the body portion 21 to form a first pole ear 221; in this case, the first tab 221 may cover a portion of the first end surface 211.

The second tab 222 is connected to the body portion 21, specifically, the second tab 222 is connected to the second tab, and the second tab 222 is located on a side of the first end surface 211 facing away from the body portion 21, and may be a portion of the second tab extending and protruding from the body portion 21, and is bent to a side of the first end surface 211 facing away from the body portion 21 to form the second tab 222; in this case, the second tab 222 may cover a portion of the second end face 212.

The second tab 222 and the first tab 221 are insulated from each other, and specifically, the insulation between the second tab 222 and the first tab 221 may be achieved by providing the insulating member 4 between the second tab 222 and the first tab 221, or the insulation between the second tab 222 and the first tab 221 may be achieved by providing the second tab 222 and the first tab 221 at a distance from each other.

The first tab 221 and the second tab 222 extend from the same side of the body 21, so that the overall space utilization in the battery can be improved, and the first tab 221 and the second tab 222 can be respectively connected with the positive electrode post 51 and the negative electrode post 52 on the same side of the battery shell, i.e. the first tab 221 and the second tab 222 are not electrically connected with the battery shell; or, the first tab 221 or the second tab 222 is electrically connected with the battery housing, for example, the first tab 221 and the second tab 222 are respectively and correspondingly connected with the battery housing and the electrode post, and the battery housing is used as an electrode leading-out end of the battery, so that connection during subsequent battery grouping can be facilitated, the area of the battery housing is relatively large, and a reliable overcurrent area during battery grouping can be ensured, so that the overall charge and discharge rate of the battery is ensured.

In this case, in the first direction X, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 is 0.08 or more and 0.2 or less, for example, the ratio of the width of the first insulating film 31 to the width of the second insulating film 32 may be 0.09, 0.12, 0.14, 0.17, 0.19, or the like.

The first insulating film 31 is for covering a side surface of the first tab 221 near the side plate 13 and a portion of the body portion 21 near the first tab 221. The second insulating film 32 is for covering a portion of the body portion 21 facing away from the first tab 221.

Further, the resistivity of the first insulating film 31 is larger than that of the second insulating film 32; resistivity (Resistivity) is a physical quantity representing the resistance characteristics of various substances, and is made of a material having a length of 1m and a cross-sectional area of 1m ² Is equal in value to the resistivity of the conductor of such a material. It reflects the property of a substance to hinder the current flow, and it is not only related to the kind of substance, but also affected by external factors such as temperature, pressure and magnetic field. Therefore, the resistivity of the second insulating film 32 and the first insulating film 31 is a comparison in the case where external factors such as temperature, pressure, and magnetic field are the same.

Since the current needs to be transmitted through the first tab 221 and the second tab 222, and the volumes of the first tab 221 and the second tab 222 are smaller and the resistance is larger, the insulation requirements of the first tab 221 and the second tab 222 are larger; the outside of the body portion 21 is also provided with a barrier film for insulation, and thus, the insulation requirement of the body portion 21 is small. The insulation failure between the first tab 221 and the second tab 222 and the case 1 is more likely. The resistivity of the first insulating film 31 covering the tab portion 22 is larger than the resistivity of the second insulating film 32 covering the winding core, and the insulation requirements of the body portion 21 and the tab portion 22 can be ensured.

Further, the thickness of the first insulating film 31 is greater than that of the second insulating film 32, for example, the material of the first insulating film 31 and the material of the second insulating film 32 may be the same, that is, the resistivity of the first insulating film 31 is equal to that of the second insulating film 32, the first insulating film 31 with a thicker thickness may meet the higher insulation requirement of the tab portion 22, and the second insulating film 32 with a thinner thickness may meet the insulation requirement of the body portion 21; moreover, the second insulating film 32 with a smaller thickness occupies smaller space in the shell 1, so that the space utilization rate of the battery is improved, enough space is provided for the expansion of the first pole piece and the second pole piece, and enough space is also provided for the lithium ion shuttle so as to ensure the charge and discharge efficiency of the battery.

In addition, a part of the first insulating film 31 and a part of the second insulating film 32 are overlapped, and due to the problems of process errors and equipment precision, it is impossible to completely align the first insulating film 31 and the second insulating film 32 which are separately arranged, that is, there is no gap between the first insulating film 31 and the second insulating film 32 which are separately arranged, and there is no overlapping area; therefore, a partially overlapped region is provided between the first insulating film 31 and the second insulating film 32, which are provided separately, so that the insulating effect between the winding structure 2 and the case 1 can be ensured.

Specifically, a portion of the first insulating film 31 covers a side of the second insulating film 32 facing away from the winding structure 2. Specifically, a portion of the first insulating film 31 may be adhered to a side of the second insulating film 32 facing away from the winding structure 2. Under the thicker condition of first insulating film 31, the intensity of first insulating film 31 is stronger, can protect the partly of second insulating film 32 through first insulating film 31, and moreover, first insulating film 31 is located the upper end of second insulating film 32, if second insulating film 32 bonding failure, still can connect second insulating film 32 through first insulating film 31 for second insulating film 32 is difficult to peel off from winding structure 2, guarantees certain insulating effect. Of course, in other exemplary embodiments of the present disclosure, a portion of the second insulating film 32 may be adhered to a side of the first insulating film 31 facing away from the winding structure 2.

Referring to fig. 2 to 4, the cylindrical battery may further include an insulating member 4, the insulating member 4 being disposed within the case 1 and between the winding structure 2 and the case 1, the first insulating film 31 and/or the second insulating film 32 being fixed to the insulating member 4.

Specifically, the winding structure 2 has two end surfaces disposed opposite to each other in the first direction X, and the insulator 4 may include an insulator body portion 41 and a stopper portion 42. The insulating body portion 41 is located between at least one end face and the housing 1; specifically, referring to fig. 4, in the case where the first tab 221 and the second tab 222 may extend from the same side of the body portion 21 of the winding structure 2, two current collecting plates 6 are provided between the first tab 221 and the second tab 222 and the case 1, the two current collecting plates 6 are connected to the first tab 221 and the second tab 222 in one-to-one correspondence, and the insulator 4 may be used to fix and insulate the first tab 221 and the second tab 222; the insulator 4 may be provided in one, the insulator body portion 41 is located between the first and second tabs 221 and 222 and the case 1, and the first insulating film 31 is fixed to the insulator 4.

Referring to fig. 2, in the case where the first tab 221 and the second tab 222 may extend from opposite sides of the body portion 21 of the winding structure 2, and the first tab 221 and the second tab 222 are respectively drawn out through the positive electrode post 51 and the negative electrode post 52, one current collecting plate 6 is provided between the first tab 221 and the case 1, one current collecting plate 6 is also provided between the second tab 222 and the case 1, the insulating members 4 may be provided in two, the insulating body portion 41 of one insulating member 4 is located between the first tab 221 and the case 1, the insulating body portion 41 of the other insulating member 4 is located between the second tab 222 and the case 1, the two insulating members 4 may be used to fix the two current collecting plates 6, respectively, and insulate the two current collecting plates 6 from the case 1, the first insulating film 31 is fixed to one insulating member 4, and the second insulating film 32 is fixed to the other insulating member 4.

Referring to fig. 3, in a case where the first tab 221 and the second tab 222 may extend from opposite sides of the body portion 21 of the winding structure 2 and the first tab 221 is led out through the positive electrode post 51 and the second tab 222 is connected to the case, one current collecting plate 6 is provided between the first tab 221 and the case 1, the insulating member 4 may be provided one, the insulating body portion 41 is located between the first tab 221 and the case 1, the insulating member 4 may be used to fix the current collecting plate 6 and insulate the current collecting plate 6 from the case 1, and the first insulating film 31 is fixed to the insulating member 4.

Of course, in other example embodiments of the present disclosure, the insulator 4 is provided on the side close to the second insulating film 32, and in the case where the insulator 4 is not provided on the side close to the first insulating film 31, it may be that the second insulating film 32 is fixed to the insulator 4.

The stopper 42 is connected to a side of the insulating body 41 near the winding structure 2, and the first insulating film 31 and/or the second insulating film 32 are fixed to the stopper 42. The limiting portion 42 may be configured in a cylindrical shape, the limiting portion 42 is configured in a shape adapted to the winding structure, for example, the winding structure is configured in a cylindrical shape, and the limiting portion 42 is configured in a cylindrical shape. Under this condition, the limiting part 42 can be arranged on one side of the first insulating film 31 deviating from the winding structure in a surrounding manner, and the limiting part 42 is in interference fit with one side of the first insulating film 31 deviating from the winding structure, so that the first insulating film 31 can be fixed through the limiting part 42, even if the adhesive between the first insulating film 31 and the winding structure 2 fails, the first insulating film 31 is separated from the winding structure 2, the first insulating film 31 cannot be stripped from the winding structure 2, and the insulating effect between the winding structure 2 and the shell 1 is ensured. Of course, when the insulator 4 is provided on the side close to the second insulating film 32, the second insulating film 32 may be fixed to the stopper 42 in the same manner as described above, and the description thereof will not be repeated here.

Further, as shown in fig. 5, the limiting portion 42 is provided with a groove 421 extending along the first direction X, and specifically, for example, a groove 421 may be provided on the cylindrical limiting portion 42; two grooves 421 may be provided on the cylindrical stopper 42 to form two stopper plates; three grooves 421 may be provided in the cylindrical stopper 42 to form three stopper plates. Providing the groove 421 facilitates the assembly of the insulator 4.

In other exemplary embodiments of the present disclosure, an adhesive layer or a hot-melt connection portion is provided between the first insulating film 31 and/or the second insulating film 32 and the limiting portion 42, that is, an adhesive layer or a hot-melt connection portion may be provided between the first insulating film 31 and the limiting portion 42, an adhesive layer or a hot-melt connection portion may be provided between the second insulating film 32 and the limiting portion 42, and an adhesive layer or a hot-melt connection portion may be provided between the first insulating film 31 and the second insulating film 32 and the limiting portion 42; for example, the first insulating film 31 and the stopper 42 may be bonded together by an adhesive layer formed by an adhesive, or the first insulating film 31 and the stopper 42 may be bonded together by a hot-melt connection portion formed by hot-melt.

The references to "parallel", "perpendicular" in this application are not entirely parallel, perpendicular, but rather are to some degree of error; for example, the included angle between the two is greater than or equal to 0 ° and less than or equal to 5 °, i.e. the two are considered to be parallel to each other; the included angle between the two is more than or equal to 85 degrees and less than or equal to 95 degrees, namely the two are considered to be mutually perpendicular.

Other embodiments of the disclosure will be apparent to those skilled in the art from consideration of the specification and practice of the disclosure disclosed herein. This application is intended to cover any adaptations, uses, or adaptations of the disclosure following, in general, the principles of the disclosure and including such departures from the present disclosure as come within known or customary practice within the art to which the disclosure pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the disclosure being indicated by the following claims.

Claims (11)

1. A cylindrical battery, comprising:

a winding structure including a body portion and a tab portion connected to each other, the tab portion being located on at least one side of a first direction of the body portion, the first direction being parallel to an axial direction of the cylindrical battery;

a first insulating film provided on a circumferential outer surface of the winding structure and covering at least a part of the tab portion and a part of the body portion;

and a second insulating film provided on the circumferential outer surface of the winding structure, the second insulating film covering at least a portion of the body portion, wherein a ratio of a width of the first insulating film to a width of the second insulating film in the first direction is 0.05 or more and 0.4 or less.

2. The cylindrical battery according to claim 1, wherein a ratio of a width of the first insulating film to a width of the second insulating film is 0.1 or more and 0.2 or less in the first direction.

3. The cylindrical battery of claim 1, wherein the cylindrical battery further comprises:

the winding structure is arranged in the shell;

and the insulating piece is arranged in the shell and positioned between the winding structure and the shell, and the first insulating film and/or the second insulating film are/is fixed on the insulating piece.

4. A cylindrical battery according to claim 3, wherein the winding structure has two end faces disposed opposite to each other in the first direction, and the insulating member comprises:

an insulating body part located between at least one of the end faces and the housing;

and the limiting part is connected to one side, close to the winding structure, of the insulating body part, and the first insulating film and/or the second insulating film are/is fixed to the limiting part.

5. The cylindrical battery according to claim 4, wherein the stopper portion is provided with a groove extending in the first direction.

6. The cylindrical battery according to claim 4, wherein an adhesive layer or a hot-melt connection portion is provided between the first insulating film and/or the second insulating film and the stopper portion.

7. The cylindrical battery according to any one of claims 1 to 6, wherein a portion of the first insulating film is provided so as to overlap a portion of the second insulating film.

8. The cylindrical battery of claim 7, wherein a portion of the first insulating film covers a side of the second insulating film facing away from the rolled structure.

9. The cylindrical battery according to any one of claims 1 to 6, wherein the body portion has a first end face and a second end face that are disposed opposite to each other in the first direction, and the tab portion includes:

the first tab is connected to the body part and is positioned at one side of the first end face away from the body part;

the second lug is connected with the body part and is positioned at one side of the second end face away from the body part;

the first insulating film covers at least part of the first tab, the second insulating film also covers at least part of the second tab, and in the first direction, the ratio of the width of the first insulating film to the width of the second insulating film is 0.15 or more and 0.35 or less.

10. The cylindrical battery according to any one of claims 1 to 6, wherein the body portion has a first end face and a second end face that are disposed opposite to each other in the first direction, and the tab portion includes:

the first tab is connected to the body part and is positioned at one side of the first end face away from the body part;

the second lug is connected with the body part and is positioned at one side of the first end face away from the body part;

in the first direction, a ratio of a width of the first insulating film to a width of the second insulating film is 0.08 or more and 0.2 or less.

11. The cylindrical battery according to claim 10, wherein a thickness of the first insulating film is larger than a thickness of the second insulating film, and/or a resistivity of the first insulating film is larger than a resistivity of the second insulating film.