CN112310514A

CN112310514A - Lithium ion battery

Info

Publication number: CN112310514A
Application number: CN202011162251.1A
Authority: CN
Inventors: 高冲; 程辉; 吴德
Original assignee: Hefei Guoxuan High Tech Power Energy Co Ltd
Current assignee: Hefei Gotion High Tech Power Energy Co Ltd
Priority date: 2020-10-27
Filing date: 2020-10-27
Publication date: 2021-02-02

Abstract

The present invention provides a lithium ion battery, comprising: the shell comprises a shell body and a cover plate covering the shell body; the cover plate has a recess recessed toward the case body; a positive pole column and a negative pole column are arranged in the concave part; a winding core group accommodated in the case body; the winding core group is provided with a matching end matched with the cover plate; the matching end is provided with a positive electrode lug and a negative electrode lug; the positive tab is electrically connected with the positive post, and the negative tab is electrically connected with the negative post; the cover plate comprises a body part and the recessed part; the surface of the body part on one side back to the shell body is flush with the surfaces of the positive pole column and the negative pole column on one side back to the shell body. The invention provides a lithium ion battery, which can improve the volume density of capacity and can enhance the mechanical strength of a cover plate.

Description

Lithium ion battery

Technical Field

The present invention relates to a lithium ion battery.

Background

Present power lithium cell is with rolling up the core assembly and getting into the aluminum hull after, still has certain clearance between apron subassembly and the core body of rolling up to be utilized, causes the capacity bulk density of lithium cell to obtain effectively promoting. On the other hand, the traditional cover plate component is of a flat plate type structure, and the defects of deformation and the like easily occur in the assembling and welding processes of the traditional cover plate component, so that the quality of the lithium battery is seriously influenced.

Therefore, it is necessary to provide a lithium ion battery to solve the above problems.

Disclosure of Invention

The invention aims to provide a lithium ion battery which can improve the volume density of capacity and can enhance the mechanical strength of a cover plate.

The above object of the present invention can be achieved by the following technical solutions: a lithium ion battery, comprising: the shell comprises a shell body and a cover plate covering the shell body; the cover plate has a recess recessed toward the case body; a positive pole column and a negative pole column are arranged in the concave part; a winding core group accommodated in the case body; the winding core group is provided with a matching end matched with the cover plate; the matching end is provided with a positive electrode lug and a negative electrode lug; the positive tab is electrically connected with the positive post, and the negative tab is electrically connected with the negative post.

As a preferred embodiment, the cover plate includes a body portion and the recessed portion; the surface of the body part on one side back to the shell body is flush with the surfaces of the positive pole column and the negative pole column on one side back to the shell body.

As a preferred embodiment, the mating end includes a first mating portion mating with the body portion and a second mating portion mating with the recessed portion; the first fitting portion protrudes outward from the second fitting portion.

As a preferred embodiment, the number of the body portions is two; the recessed part is arranged between the two body parts, and a U-shaped structure is formed between the recessed part and the two body parts.

In a preferred embodiment, the number of the first fitting portions is two, and the positive tab is disposed between one of the first fitting portions and one of the main body portions; the negative electrode tab is arranged between the other first matching part and the other body part; and the positive electrode lug and the negative electrode lug are respectively and electrically connected with the positive pole column and the negative pole column through connecting sheets.

In a preferred embodiment, the positive electrode tab and the negative electrode tab are both disposed between the second fitting portion and the recess portion.

As a preferred embodiment, there are two of the recesses; the body part is arranged between the two sunken parts, and a U-shaped structure is formed between the body part and the two sunken parts.

As a preferred embodiment, there are two of the recesses; the number of the body parts is three; the concave parts and the body parts are alternately arranged; and a double-U-shaped structure is formed between the two sunken parts and the three body parts.

In a preferred embodiment, there are two second matching parts, and the positive tab is disposed between one second matching part and one recess; the negative electrode tab is arranged between the other second matching part and the other concave part.

In a preferred embodiment, the positive tab and the negative tab are both disposed between the first mating portion and the body portion, and the positive tab and the negative tab are both electrically connected to the positive post and the negative post through connecting pieces.

In a preferred embodiment, there are two second engaging portions, and the positive tab and the negative tab are disposed on one side of one of the second engaging portions; and the positive pole lug and the negative pole lug are respectively and electrically connected with the positive pole column and the negative pole column through connecting pieces.

The application provides a lithium ion battery's beneficial effect is: the lithium ion battery provided by the embodiment of the application is provided with the matching end which is matched with the cover plate, and the cover plate is provided with the depressed part depressed towards the shell body; the side of the concave part back to the shell body is provided with a positive pole column and a negative pole column. So make the clearance that exists between apron and the book core reduce, and then promote lithium ion battery's capacity bulk density, and strengthened the mechanical strength of apron. Therefore, the invention provides a lithium ion battery which can improve the volume density of the capacity and can enhance the mechanical strength of the cover plate.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic view of an overall structure of a lithium ion battery according to a first embodiment of the present application;

FIG. 2 is a schematic structural diagram of a cover plate according to an embodiment of the present disclosure;

FIG. 3 is a schematic structural diagram of a housing body according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural view of a winding core set according to an embodiment of the present invention;

FIG. 5 is a front view of the assembled winding core assembly and cover plate according to one embodiment of the present invention;

FIG. 6 is a front view of the assembled winding core assembly and cover plate according to the second embodiment of the present application;

FIG. 7 is a schematic structural diagram of a cover plate according to a second embodiment of the present application;

fig. 8 is a schematic view of an overall structure of a lithium ion battery in the third embodiment of the present application;

FIG. 9 is a front view of the assembled winding core assembly and cover plate according to the third embodiment of the present application;

FIG. 10 is a front view of the assembled winding core assembly and cover plate according to the fourth embodiment of the present application;

fig. 11 is a schematic view of an overall structure of a lithium ion battery according to a fifth embodiment of the present application;

FIG. 12 is a front view of the assembled winding core assembly and cover plate according to the fifth embodiment of the present invention;

fig. 13 is a front view of the assembled winding core assembly and cover plate according to the sixth embodiment of the present application;

fig. 14 is a schematic view of an overall structure of a lithium ion battery according to a seventh embodiment of the present application;

fig. 15 is a front view of the assembled winding core assembly and cover plate in the seventh embodiment of the present application.

Description of reference numerals:

13. a housing body; 14. a cover plate; 15. a winding core group; 17. a positive post; 19. a negative pole post; 21. a recessed portion; 22. a positive tab; 25. a negative tab; 27. a mating end; 31. a body portion; 32. a first mating portion; 33. a second mating portion; 35. connecting sheets; 37. an explosion-proof valve; 39. and a liquid injection hole.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Please refer to fig. 1 to 15. An embodiment of the present application provides a lithium ion battery, which may include: a housing including a housing body 13 and a cover plate 14 covering the housing body 13; the cover plate 14 has a recess 21 recessed toward the case body 13; the concave part 21 is internally provided with a positive pole post 17 and a negative pole post 19; a winding core group 15 housed in the case body 13; the winding core set 15 is provided with a matching end 27 matched with the cover plate 14; the mating end 27 is provided with a positive tab 22 and a negative tab 25; the positive tab 22 is electrically connected to the positive post 17, and the negative tab 25 is electrically connected to the negative post 19.

The technical scheme shows that: the lithium ion battery according to the embodiment of the present application is provided with a mating end 27, the mating end 27 is mated with the cover plate 14, and the cover plate 14 has a recess 21 recessed toward the case body 13; positive electrode tab 17 and negative electrode tab 19 are provided in recessed portion 21. So make the clearance between apron 14 and the roll core group 15 reduce through depressed part 21 to effectively utilize the space in the depressed part 21 through positive post 17 and negative pole post 19, and make this application embodiment lithium ion battery form regular structure, and then promote lithium ion battery's capacity bulk density, and strengthened the mechanical strength of apron 14.

In the present embodiment, the casing has a rectangular shape having a hollow structure as a whole. The hollow part forms an accommodating space. Of course, the housing is not limited to a rectangular shape, and may have other shapes such as a columnar shape. Further, as shown in fig. 1, for example, the housing includes a housing body 13 and a cover plate 14 provided to cover the housing body 13. Further, the cover plate 14 has a recess 21 recessed toward the case body 13. The recess 21 is recessed downward as shown in fig. 2, for example. Further, positive electrode tab 17 and negative electrode tab 19 are provided in this recessed portion 21. For example, as shown in fig. 2, positive post 17 and negative post 19 are housed in recessed portion 21. Further, as shown in fig. 2, for example, the cover plate 14 is provided with an explosion-proof valve 37 and a liquid injection hole 39.

In the present embodiment, the core group 15 is housed in the case body 13. That is, the winding core group 15 is accommodated in the accommodating space. Further, the core package 15 has a mating end 27 that mates with the cover 14. The mating may be such that the mating end 27 is shaped to conform to the shape of the cover 14. The mating end 27 is the upper end of the core package 15, as shown, for example, in fig. 5. The cover plate 14 is in the shape of an inverted U. The mating end 27 is an inverted U-shape that mates with the cover 14. Of course, the cover plate 14 is not limited to a U-shape, for example, as shown, the cover plate 14 is a right U-shape. The mating end 27 is now a right U-shape that mates with the cover 14. Further, positive and

negative electrode tabs

22 and 25 are disposed on the mating end 27. Positive tab 22 is electrically connected to positive post 17 and negative tab 25 is electrically connected to negative post 19. So through the cooperation of cooperation end 27 and apron 14 make the clearance that exists between apron 14 and the core group 15 reduce, and then promote lithium ion battery's capacity bulk density, and strengthened the mechanical strength of apron 14.

Further, in the present embodiment, the core set 15 includes two cores connected in parallel. For example, as shown in fig. 5, two cores are fixed by tape after they are manufactured by a lamination process. Of course, the core is not limited to being manufactured by a lamination process, and may be manufactured by other processes, such as a winding process, and the like, and the application is not limited thereto.

In one embodiment, the cover plate 14 includes a body portion 31 and a recessed portion 21. The surface of body portion 31 on the side facing away from can body 13 is flush with the surfaces of positive and

negative posts

17 and 19 on the side facing away from can body 13. For example, as shown, there are two recesses 21. The body portion 31 is located between the two recessed portions 21. And the upper surface of positive post 17 and negative pole post 19 is the same level with the upper surface of this somatic part 31, so make positive post 17 and negative pole post 19 can be in the up-down direction with this somatic part 31 sharing space, and then reduce the clearance between apron 14 and roll core group 15 through depressed part 21, and effectively utilize the space in the depressed part 21 through positive post 17 and negative pole post 19, and make this application embodiment lithium ion battery form regular structure, and then promote lithium ion battery's capacity bulk density, and strengthened the mechanical strength of apron 14.

Further, the mating end 27 includes a first mating portion 32 mating with the body portion 31 and a second mating portion 33 mating with the recess 21; the first fitting portion 32 projects outwardly of the second fitting portion 33. For example, as shown, there are two second mating portions 33. The number of the first fitting portions 32 is 1. The first fitting portion 32 projects upward from the second fitting portion 33. Thus, the first fitting portion 32 faces the body portion 31 as shown in the drawing. The second fitting portion 33 faces the recess 21.

Further, please refer to fig. 1 to 5. Fig. 1 is a schematic view of an overall structure of a lithium ion battery according to a first embodiment of the present application. Fig. 2 is a schematic structural diagram of the cover plate 14 in the first embodiment of the present application; fig. 3 is a schematic structural diagram of the housing body 13 in an embodiment of the present application. Fig. 4 is a schematic structural diagram of the winding core group 15 in the first embodiment of the present application. Fig. 5 is a front view of the assembled winding core assembly 15 and cover plate 14 according to the first embodiment of the present application. The specific structure of the lithium ion battery in the first embodiment will be described with reference to fig. 1 to 2.

Specifically, in the first embodiment of the present application, there are two recesses 21. The main body 31 is disposed between the two recessed portions 21, and a U-shaped structure is formed between the main body 31 and the two recessed portions 21. That is, as shown in fig. 2, in the first embodiment of the present application, the cover plate 14 has an inverted U shape.

Further, the second fitting portion 33 is two. The number of the first fitting portions 32 is 1. Two second fitting portions 33 are provided at both ends of the first fitting portion 32. The first fitting portion 32 faces the body portion 31. Each second fitting portion 33 faces 1 recess 21. That is, as shown in fig. 4, in the first embodiment of the present application, the mating end 27 has an inverted U shape.

Further, the positive tab 22 is disposed between a second mating portion 33 and a recess 21; negative electrode tab 25 is disposed between the other second fitting portion 33 and the other recess portion 21. As shown in the drawing, positive tab 22 and negative tab 25 are provided on 1 second engaging portion 33, respectively. So that the positive tab 22 and the negative tab 25 can be electrically connected to the positive post 17 and the negative post 19 in the two recesses 21, respectively. Thus, the positive tab 22 and the negative tab 25 can utilize the gap between the second matching portion 33 and the concave portion 21, thereby improving the volume density of the lithium ion battery.

Further, please refer to fig. 6 to 7. Fig. 6 is a front view of the assembled winding core assembly 15 and cover plate 14 according to the second embodiment of the present application. Fig. 7 is a schematic structural diagram of the cover plate 14 in the second embodiment of the present application. The specific structure of the lithium ion battery in the second embodiment will be described with reference to fig. 6 to 7.

Specifically, in the second embodiment of the present application, there are two recesses 21. The main body 31 is disposed between the two recessed portions 21, and a U-shaped structure is formed between the main body 31 and the two recessed portions 21. That is, as shown in fig. 6, in the second embodiment of the present application, the cover plate 14 has an inverted U shape.

Further, the second fitting portion 33 is two. The number of the first fitting portions 32 is 1. Two second fitting portions 33 are provided at both ends of the first fitting portion 32. The first fitting portion 32 faces the body portion 31. Each second fitting portion 33 faces 1 recess 21. That is, as shown in fig. 6, in the second embodiment of the present application, the mating end 27 has an inverted U shape.

Further, the positive electrode tab 22 and the negative electrode tab 25 are both disposed between the first fitting portion 32 and the body portion 31. For example, as shown in fig. 6, positive tab 22 is disposed to the left of negative tab 25. Further, both the positive tab 22 and the negative tab 25 are electrically connected to the positive post 17 and the negative post 19, respectively, through the connection piece 35. As shown in fig. 7, for example, the cover plate 14 is provided with two connecting pieces 35 extending in the extending direction of the cover plate 14. And the connecting piece 35 extends from the recess 21 to the body 31. And the two connection pieces 35 are electrically connected to the positive pole post 17 and the negative pole post 19, respectively. The positive tab 22 and the negative tab 25 located between the first engaging portion 32 and the body portion 31 can be electrically connected to the two connecting pieces 35, and the positive tab 22 and the negative tab 25 can be electrically connected to the positive post 17 and the negative post 19 through the connecting pieces 35. In this way, the positive electrode tab 22 and the negative electrode tab 25 can utilize the gap between the first fitting portion 32 and the body portion 31, thereby improving the volume density of the lithium ion battery.

Further, please refer to fig. 8 to 9. Fig. 8 is a schematic view of an overall structure of a lithium ion battery in the third embodiment of the present application. Fig. 9 is a front view of the assembled winding core group 15 and cover plate 14 in the third embodiment of the present application. The specific structure of the lithium ion battery in the third embodiment will be described below with reference to fig. 8 to 9.

Specifically, in the third embodiment of the present application, there are two body portions 31. The recessed portion 21 is disposed between the two main bodies 31, and a U-shaped structure is formed between the recessed portion 21 and the two main bodies 31. That is, as shown in fig. 9, in the third embodiment of the present application, the cover plate 14 has a regular U shape. And positive post 17 and negative post 19 are located in one of the recesses 21.

Further, the number of the second fitting portions 33 is 1. The number of the first fitting portions 32 is two. The two first fitting portions 32 are disposed at both ends of the second fitting portion 33. The second fitting portion 33 faces the recess portion 21. Each of the first fitting portions 32 faces 1 of the body portion 31. That is, as shown in fig. 8, in the third embodiment of the present application, the mating end 27 has a right U shape.

Further, both positive tab 22 and negative tab 25 are disposed between second fitting portion 33 and recess 21. That is, as shown in fig. 9, positive tab 22 is disposed on the left side of negative tab 25. So that positive tab 22 and negative tab 25 can be electrically connected to positive post 17 and negative post 19, respectively, in recess 21. Thus, the positive tab 22 and the negative tab 25 can utilize the gap between the second matching portion 33 and the concave portion 21, thereby improving the volume density of the lithium ion battery.

Further, please refer to fig. 10. Fig. 10 is a front view of the assembled winding core group 15 and cover plate 14 in the fourth embodiment of the present application. The specific structure of the lithium ion battery in the fourth embodiment will be described below with reference to fig. 10.

Specifically, in the fourth embodiment of the present application, there are two body portions 31. The recessed portion 21 is disposed between the two main bodies 31, and a U-shaped structure is formed between the recessed portion 21 and the two main bodies 31. That is, as shown in fig. 10, in the fourth embodiment of the present application, the cover plate 14 has a regular U shape. And positive post 17 and negative post 19 are located in one of the recesses 21.

Further, the number of the second fitting portions 33 is 1. The number of the first fitting portions 32 is two. The two first fitting portions 32 are disposed at both ends of the second fitting portion 33. The second fitting portion 33 faces the recess portion 21. Each of the first fitting portions 32 faces 1 of the body portion 31. That is, as shown in fig. 10, in the fourth embodiment of the present application, the mating end 27 has a right U shape.

Further, there are two first fitting portions 32, and the positive tab 22 is disposed between one first fitting portion 32 and one body portion 31; the negative electrode tab 25 is disposed between the other first engaging portion 32 and the other body portion 31. As shown in the drawing, the positive electrode tab 22 and the negative electrode tab 25 are provided on 1 first engaging portion 32, respectively. Further, both the positive tab 22 and the negative tab 25 are electrically connected to the positive post 17 and the negative post 19, respectively, through the connection piece 35. As shown in fig. 10, for example, the cover plate 14 is provided with two connecting pieces 35 extending in the extending direction of the cover plate 14. And the connecting piece 35 extends from the recess 21 to the body 31. And the two connection pieces 35 are electrically connected to the positive pole post 17 and the negative pole post 19, respectively. The positive tab 22 and the negative tab 25 located between the first engaging portion 32 and the body portion 31 can be electrically connected to the two connecting pieces 35, and the positive tab 22 and the negative tab 25 can be electrically connected to the positive post 17 and the negative post 19 through the connecting pieces 35. In this way, the positive electrode tab 22 and the negative electrode tab 25 can utilize the gap between the first fitting portion 32 and the body portion 31, thereby improving the volume density of the lithium ion battery.

Further, please refer to fig. 11 to 12. Fig. 11 is a schematic view of an overall structure of a lithium ion battery in the fifth embodiment of the present application. Fig. 12 is a front view of the assembled winding core assembly 15 and cover plate 14 in the fifth embodiment of the present application. The specific structure of the lithium ion battery in the fifth embodiment will be described below with reference to fig. 11 to 12.

Specifically, in the fifth embodiment of the present application, there are two recesses 21. The number of the body portion 31 is three. The recessed portions 21 and the body portion 31 are alternately arranged. And a double U-shaped structure is formed between the two recessed portions 21 and the three body portions 31. That is, as shown in fig. 12, in the fifth embodiment of the present application, the cover plate 14 has a double U shape.

Further, the second fitting portion 33 is two. The number of the first fitting portions 32 is three. The second fitting portions 33 are alternately arranged with the first fitting portions 32. Each of the first fitting portions 32 faces the body portion 31. Each second fitting portion 33 faces 1 recess 21. That is, as shown in fig. 12, in the fifth embodiment of the present application, the mating end 27 has a double U shape.

Further, please refer to fig. 13. Fig. 13 is a front view of the winding core set 15 assembled with the cover plate 14 in the sixth embodiment of the present application. The specific structure of the lithium ion battery in the sixth embodiment will be described below with reference to fig. 13.

Specifically, in the sixth embodiment of the present application, there are two recesses 21. The number of the body portion 31 is three. The recessed portions 21 and the body portion 31 are alternately arranged. And a double U-shaped structure is formed between the two recessed portions 21 and the three body portions 31. That is, as shown in fig. 13, in the sixth embodiment of the present application, the cover plate 14 has a double U shape.

Further, the second fitting portion 33 is two. The number of the first fitting portions 32 is three. The second fitting portions 33 are alternately arranged with the first fitting portions 32. Each of the first fitting portions 32 faces the body portion 31. Each second fitting portion 33 faces 1 recess 21. That is, as shown in fig. 13, in the sixth embodiment of the present application, the mating end 27 has a double U shape.

Further, the positive electrode tab 22 and the negative electrode tab 25 are both disposed between the first fitting portion 32 and the body portion 31. For example, as shown in fig. 13, positive tab 22 is disposed to the left of negative tab 25. Further, both the positive tab 22 and the negative tab 25 are electrically connected to the positive post 17 and the negative post 19, respectively, through the connection piece 35. As shown in fig. 13, for example, the cover plate 14 is provided with two connecting pieces 35 extending in the extending direction of the cover plate 14. And the connecting piece 35 extends from the recess 21 to the body 31. And the two connection pieces 35 are electrically connected to the positive pole post 17 and the negative pole post 19, respectively. The positive tab 22 and the negative tab 25 located between the first engaging portion 32 and the body portion 31 can be electrically connected to the two connecting pieces 35, and the positive tab 22 and the negative tab 25 can be electrically connected to the positive post 17 and the negative post 19 through the connecting pieces 35. In this way, the positive electrode tab 22 and the negative electrode tab 25 can utilize the gap between the first fitting portion 32 and the body portion 31, thereby improving the volume density of the lithium ion battery.

Further, please refer to fig. 14 to 15. Fig. 14 is a schematic view of the overall structure of a lithium ion battery in the seventh embodiment of the present application. Fig. 15 is a front view of the assembled winding core group 15 and cover plate 14 in the seventh embodiment of the present application. The specific structure of the lithium ion battery in the seventh embodiment will be described below with reference to fig. 14 to 15.

Specifically, in the seventh embodiment of the present application, there are two recesses 21. The main body 31 is disposed between the two recessed portions 21, and a U-shaped structure is formed between the main body 31 and the two recessed portions 21. That is, as shown in fig. 14, in the seventh embodiment of the present application, the cover plate 14 has an inverted U shape.

Further, the second fitting portion 33 is two. The number of the first fitting portions 32 is 1. Two second fitting portions 33 are provided at both ends of the first fitting portion 32. The first fitting portion 32 faces the body portion 31. Each second fitting portion 33 faces 1 recess 21. That is, as shown in fig. 14, in the seventh embodiment of the present application, the mating end 27 has an inverted U shape.

Further, positive tab 22 and negative tab 25 are each provided on one side of one second engaging portion 33. As shown in fig. 15, for example, the positive electrode tab 22 and the negative electrode tab 25 are disposed on the left side and the right side of the winding core group 15, respectively. Further, both the positive tab 22 and the negative tab 25 are electrically connected to the positive post 17 and the negative post 19, respectively, through the connection piece 35. For example, as shown in fig. 15, two connecting pieces 35 are provided on the cover plate 14. And the connecting piece 35 extends from the recess 21 to the outside of the cover plate 14. And the two connection pieces 35 are electrically connected to the positive pole post 17 and the negative pole post 19, respectively. So that the positive tab 22 on the left side of the winding core group 15 and the negative tab 25 on the right side of the winding core group 15 can be electrically connected to the two connecting pieces 35, and the positive tab 22 and the negative tab 25 can be electrically connected to the positive post 17 and the negative post 19 through the connecting pieces 35.

It should be noted that, in the description of the present application, the terms "first", "second", and the like are used for descriptive purposes only and for distinguishing similar objects, and no precedence between the two is intended or should be construed to indicate or imply relative importance. In addition, in the description of the present application, "a plurality" means two or more unless otherwise specified.

It is to be understood that the above description is intended to be illustrative, and not restrictive. Many embodiments and many applications other than the examples provided will be apparent to those of skill in the art upon reading the above description. The scope of the present teachings should, therefore, be determined not with reference to the above description, but should instead be determined with reference to the appended claims, along with the full scope of equivalents to which such claims are entitled. The disclosures of all articles and references, including patent applications and publications, are hereby incorporated by reference for all purposes. The omission in the foregoing claims of any aspect of subject matter that is disclosed herein is not intended to forego the subject matter and should not be construed as an admission that the applicant does not consider such subject matter to be part of the disclosed subject matter.

Claims

1. A lithium ion battery, comprising:

the shell comprises a shell body and a cover plate covering the shell body; the cover plate has a recess recessed toward the case body; a positive pole column and a negative pole column are arranged in the concave part;

a winding core group accommodated in the case body; the winding core group is provided with a matching end matched with the cover plate; the matching end is provided with a positive electrode lug and a negative electrode lug; the positive tab is electrically connected with the positive post, and the negative tab is electrically connected with the negative post.

2. The lithium ion battery of claim 1, wherein the cover plate comprises a body portion and the recessed portion; the surface of the body part on one side back to the shell body is flush with the surfaces of the positive pole column and the negative pole column on one side back to the shell body.

3. The lithium ion battery of claim 2, wherein the mating end comprises a first mating portion that mates with the body portion and a second mating portion that mates with the recessed portion; the first fitting portion protrudes outward from the second fitting portion.

4. The lithium ion battery of claim 3, wherein the body portion is two; the recessed part is arranged between the two body parts, and a U-shaped structure is formed between the recessed part and the two body parts.

5. The lithium ion battery according to claim 4, wherein the first fitting portion is two, and the positive tab is disposed between one of the first fitting portions and one of the body portions; the negative electrode tab is arranged between the other first matching part and the other body part; and the positive electrode lug and the negative electrode lug are respectively and electrically connected with the positive pole column and the negative pole column through connecting sheets.

6. The lithium ion battery of claim 4, wherein the positive tab and the negative tab are both disposed between the second mating portion and the recessed portion.

7. The lithium ion battery of claim 3, wherein the number of the recesses is two; the body part is arranged between the two sunken parts, and a U-shaped structure is formed between the body part and the two sunken parts.

8. The lithium ion battery of claim 3, wherein the number of the recesses is two; the number of the body parts is three; the concave parts and the body parts are alternately arranged; and a double-U-shaped structure is formed between the two sunken parts and the three body parts.

9. The lithium ion battery according to claim 7 or 8, wherein the number of the second fitting portions is two, and the positive tab is disposed between one of the second fitting portions and one of the recessed portions; the negative electrode tab is arranged between the other second matching part and the other concave part.

10. The lithium ion battery of claim 7 or 8, wherein the positive tab and the negative tab are both disposed between the first mating portion and the body portion, and the positive tab and the negative tab are both electrically connected to the positive post and the negative post through connecting tabs, respectively.

11. The lithium ion battery of claim 7, wherein there are two second engaging portions, and the positive tab and the negative tab are disposed on one side of one of the second engaging portions; and the positive pole lug and the negative pole lug are respectively and electrically connected with the positive pole column and the negative pole column through connecting pieces.