CN212695228U

CN212695228U - Lithium ion battery

Info

Publication number: CN212695228U
Application number: CN202021495214.8U
Authority: CN
Inventors: 游坤; 华秉杨; 宋贺; 黄天翔
Original assignee: Dongguan Tafel New Energy Technology Co Ltd; Jiangsu Tafel New Energy Technology Co Ltd; Jiangsu Tafel Power System Co Ltd
Current assignee: Jiangsu Zenio New Energy Battery Technologies Co Ltd
Priority date: 2020-07-23
Filing date: 2020-07-23
Publication date: 2021-03-12
Anticipated expiration: 2030-07-23

Abstract

The utility model belongs to the technical field of the battery, especially, relate to a lithium ion battery, including the casing and encapsulate in the inside naked electric core of casing, the casing is including relative first lateral wall and the second lateral wall that sets up, first lateral wall with the second lateral wall all include with naked electric core lateral part assorted laminating portion. Compared with the prior art, the utility model discloses optimize the atress of naked electric core arc position, reduce the clearance of naked electric core and casing, improve space utilization.

Description

Lithium ion battery

Technical Field

The utility model belongs to the technical field of the battery, especially, relate to a lithium ion battery.

Background

The lithium ion battery has the advantages of high energy density, high working voltage, wide use temperature, long service life, environmental friendliness and the like, is widely applied to the fields of consumer mobile phones, electric tools, medical electronics and the like, and simultaneously has good application prospects in the fields of new energy automobiles, energy storage base stations and the like.

Lithium ion batteries can be mainly classified into three major types, i.e., cylindrical lithium ion batteries, square lithium ion batteries, and flexible package lithium ion batteries, according to the packaging form. Different configurations imply different advantages and disadvantages. Referring to fig. 1, the square battery is generally an aluminum-shell or steel-shell square battery, and the square battery has a simple structure and high mechanical strength, and is not prone to liquid leakage and other risks. However, the naked electric core 2 of the square lithium ion battery mostly adopts a winding structure, and the two sides of the naked electric core 2 are arc-shaped structures 20, which have the following disadvantages: 1) after the naked electric core 2 is assembled, the top of the arc-shaped structure 20 is tightly attached to the side surface of the shell 1, the top is stressed, other parts of the arc-shaped structure 20 have no binding force, the stress is uneven due to expansion in the circulation process, and the risk of deformation and fracture exists locally; 2) the gap between the arc-shaped structure 20 of the bare cell 2 and the side surface of the shell 1 is large, and partial free electrolyte can be stored, so that the utilization rate of the electrolyte is not high; 3) the clearance between the corner of the naked electric core 2 and the shell 1 is large, and the heat transfer effect is poor.

SUMMERY OF THE UTILITY MODEL

The utility model aims to provide a: to prior art's not enough, and provide a lithium ion battery, optimize the atress of naked electric core arc position, reduce the clearance of naked electric core and casing, improve space utilization.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides a lithium ion battery, including the casing and encapsulate in the inside naked electric core of casing, the casing is including relative first lateral wall and the second lateral wall that sets up, first lateral wall with the second lateral wall all include with naked electric core lateral part assorted laminating portion.

As an improvement of the lithium ion battery, the laminating part is in the shape of an arc or an elliptic arc, and the radian of the laminating part is 90-150 degrees.

As an improvement of the lithium ion battery of the present invention, the thickness of the attaching portion gradually decreases from the edge region to the middle region thereof.

As an improvement of the lithium ion battery, the thickness of the edge region of the laminating part is larger than the thickness of the middle region of the laminating part by 0-0.5 mm.

As an improvement of the lithium ion battery, the thickness of the middle area of the laminating part is 0.2-2 mm.

As a lithium ion battery's an improvement, laminating portion is provided with at least one, adjacent two laminating portion interconnect.

As a lithium ion battery's an improvement, the quantity of laminating portion with the quantity of naked electric core is the same.

As an improvement of the lithium ion battery, the casing further includes a third side wall and a fourth side wall which are arranged relatively, the third side wall and the fourth side wall both with the first side wall and the second side wall are connected to form a frame body, the third side wall and the fourth side wall are planar.

As an improvement of the lithium ion battery, the housing further includes a bottom plate, the bottom plate being disposed at an end of the frame body.

As an improvement of the lithium ion battery, the lithium ion battery further comprises a top cover, wherein the shape of the top cover is matched with the opening shape of the shell.

Compared with the prior art, the beneficial effects of the utility model include but are not limited to:

1) the utility model discloses a first lateral wall and the second lateral wall of its casing of lithium ion battery all be provided with naked electric core lateral part assorted laminating portion for the whole arc structure of its lateral part of naked electric core is inseparable with the casing laminating, and the atress is even, prevents that the pole piece from leading to the fracture because of local atress is uneven among the cyclic process.

2) The utility model discloses a first lateral wall and the second lateral wall of its casing of lithium ion battery all be provided with naked electric core lateral part assorted laminating portion for the whole arc structure and the casing laminating of its lateral part of naked electric core are inseparable, thereby have reduced the space between the two, have improved space utilization, reduce free electrolyte solution volume, reduce the liquid retention volume.

3) The utility model discloses a first lateral wall and the second lateral wall of its casing of lithium ion battery all be provided with naked electric core lateral part assorted laminating portion for the whole arc structure of its lateral part of naked electric core is inseparable with the casing laminating, has increased the area of contact of naked electric core and casing, has increased heat transfer area, is favorable to the outside heat dissipation of naked electric core.

Drawings

Fig. 1 is a schematic diagram of an assembly structure of a bare cell and a casing in the prior art.

Fig. 2 is one of the assembling structure schematic diagrams of the bare cell and the shell in the present invention.

Fig. 3 is a second schematic view of the assembly structure of the bare cell and the housing of the present invention.

Fig. 4 is one of the assembling structural diagrams of the middle top cover and the housing of the present invention.

Fig. 5 is a second schematic view of the assembly structure of the middle cap and the housing according to the present invention.

Wherein: the battery comprises a shell 1, a naked battery cell 2, a top cover 3, a first side wall 11, a second side wall 12, a third side wall 13, a fourth side wall 14, a fitting part 10, an arc-shaped structure 20, an arc-shaped part 30 and an electrode terminal 31.

Detailed Description

As used in the specification and in the claims, certain terms are used to refer to particular components. As one skilled in the art will appreciate, manufacturers may refer to a component by different names. This specification and claims do not intend to distinguish between components that differ in name but not function. In the following description and in the claims, the terms "include" and "comprise" are used in an open-ended fashion, and thus should be interpreted to mean "include, but not limited to. "substantially" means within an acceptable error range, within which a person skilled in the art can solve the technical problem to substantially achieve the technical result.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", horizontal "and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention.

In the present invention, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "fixed" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

The present invention will be described in further detail with reference to the accompanying drawings, which are not intended to limit the present invention.

The utility model discloses a lithium ion battery includes casing 1 and encapsulates in the inside naked electric core 2 of casing 1, and casing 1 is including relative first side wall 11 and the second side wall 12 that sets up, and first side wall 11 and second side wall 12 all include with 2 lateral part assorted laminating portions 10 of naked electric core. It should be noted that, matching means that at least 75% of the area of the inner side surface of the attaching portion 10 is attached to the side portion (here, the side portion having an arc-shaped structure) of the bare cell 2.

The inventor finds that the first side wall 11 and the second side wall 12 of the shell 1 are provided with the fitting part 10 matched with the side part of the bare cell 2, so that the whole arc-shaped structure 20 of the side part of the bare cell 2 is tightly fitted with the shell 1, and further has the following beneficial effects: 1) the arc-shaped structure 20 at the side part of the bare cell 2 is uniformly stressed, so that the pole piece is prevented from being broken due to nonuniform local stress in the circulating process; 2) the gap between the bare cell 2 and the shell 1 is reduced, the space utilization rate is improved, the free electrolyte amount is reduced, and the liquid retention amount is reduced; 3) the contact area of naked electric core 2 and casing 1 has been increased, has increased heat transfer area, is favorable to the outside heat dissipation of naked electric core 2.

Specifically, the fitting portion 10 is arc-shaped or elliptical-arc-shaped, and the radian of the fitting portion 10 is 90 ° to 150 °. Generally, the radian of the arc structure 20 that naked electric core 2 lateral part formed is about 90 ~ 150, and the radian of laminating portion 10 approximately equals naked electric core 2 lateral part arc structure 20's radian for when can laminating comparatively inseparable between the two, also can not cause the damage to naked electric core 2.

Specifically, the thickness of the attaching portion 10 gradually decreases from the edge region thereof to the middle region thereof. Preferably, the thickness of the edge region of the bonded part 10 is 0 to 0.5mm greater than the thickness of the middle region of the bonded part 10. The marginal zone of laminating portion 10 is thicker, and the middle zone is thinner, forms the trend of diminishing gradually, effectively improves 1 intensity at corner casing, makes the casing 1 of corner and the laminating of naked electric core 2 compacter simultaneously. The middle region is a region where the bonded portion 10 extends 0 to 1cm to the left and right of the symmetry axis thereof, and the edge region is a region other than the middle region.

Specifically, the thickness of the middle area of the bonding part 10 is 0.2-2 mm. The thickness of middle zone is too thin can reduce the intensity of casing 1, reduces the guard action to naked electric core 2. And when the thickness of middle zone was too thick, can influence the laminating effect of casing 1 and naked electric core 2 again.

Specifically, the number of the fitting portions 10 is the same as the number of the bare cells 2. At least one attaching portion 10 is provided, and two adjacent attaching portions 10 are connected to each other. Referring to fig. 2, in some embodiments, there is only one bare cell 2, and there is only one fitting portion 10. Referring to fig. 3, in other embodiments, two or more bare cells 2 are provided, two or more fitting portions 10 are also provided, and two adjacent fitting portions 10 are connected to each other.

Specifically, the housing 1 further includes a third sidewall 13 and a fourth sidewall 14 disposed opposite to each other, one end of the first sidewall 11 is connected to the third sidewall 13, the other end of the first sidewall 11 is connected to the fourth sidewall 14, one end of the second sidewall 12 is connected to the third sidewall 13, and one end of the second sidewall 12 is connected to the fourth sidewall 14. The first side wall 11, the third side wall 13, the second side wall 12 and the fourth side wall 14 are connected in sequence to form a frame. Specifically, the third side wall 13 and the fourth side wall 14 are both planar. The housing 1 may be made of a conductive metal material such as aluminum or aluminum alloy, or may be made of an insulating material such as plastic.

Specifically, the housing 1 further includes a bottom plate (not shown) disposed at one end of the frame to form a housing 1 having an opening at only one end. Preferably, the bottom plate and the frame are integrally formed.

Referring to fig. 4-5, the lithium ion battery of the present invention further includes a top cap 3, wherein the shape of the top cap 3 matches with the opening shape of the housing 1. The two sides of the top cover 3 are provided with arc parts 30, and the arc parts 30 are matched with the attaching parts 10. The top cover is sealed at the opening of the shell 1. The top cover 3 is the same as the conventional top cover except that the shape thereof is different from that of the conventional top cover, and further includes an electrode terminal 31, an explosion-proof valve (not shown), a liquid inlet (not shown), and the like.

The utility model discloses a naked electric core 2 preferred is the naked electric core of coiling among the lithium ion battery, and its both sides portion of the naked electric core of coiling is formed with arc structure 20.

While the foregoing description shows and describes several preferred embodiments of the invention, it is to be understood, as noted above, that the invention is not limited to the forms disclosed herein, but is not intended to be exhaustive of other embodiments, and is capable of use in various other combinations, modifications, and environments and is capable of changes within the scope of the inventive concept as expressed above, or as otherwise known in the relevant art. But that modifications and variations may be effected by those skilled in the art without departing from the spirit and scope of the invention, which is to be limited only by the claims appended hereto.

Claims

1. The utility model provides a lithium ion battery, including the casing and encapsulate in the inside naked electric core of casing, its characterized in that, the casing is including relative first lateral wall and the second lateral wall that sets up, first lateral wall with the second lateral wall all include with naked electric core lateral part assorted laminating portion.

2. The lithium ion battery according to claim 1, wherein the fitting portion has an arc shape or an elliptical arc shape, and the arc degree of the fitting portion is 90 ° to 150 °.

3. The lithium ion battery according to claim 1, wherein the thickness of the fitting portion gradually decreases from an edge region thereof to a middle region thereof.

4. The lithium ion battery according to claim 1, wherein the thickness of the edge region of the bonding part is 0-0.5 mm greater than the thickness of the middle region of the bonding part.

5. The lithium ion battery according to claim 1, wherein the thickness of the middle region of the bonding part is 0.2-2 mm.

6. The lithium ion battery according to claim 1, wherein at least one of the bonding portions is provided, and two adjacent bonding portions are connected to each other.

7. The lithium ion battery of claim 6, wherein the number of the fitting portions is the same as the number of the bare cells.

8. The lithium ion battery of claim 1, wherein the housing further comprises a third sidewall and a fourth sidewall that are disposed opposite to each other, wherein the third sidewall and the fourth sidewall are both connected to the first sidewall and the second sidewall to form a frame, and the third sidewall and the fourth sidewall are both planar.

9. The lithium ion battery of claim 8, wherein the housing further comprises a bottom plate disposed at an end of the frame.

10. The lithium ion battery of any one of claims 1-9, further comprising a top cover, wherein the shape of the top cover matches the shape of the opening of the housing.